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v6.8
   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 *  Freescale lpuart serial port driver
   4 *
   5 *  Copyright 2012-2014 Freescale Semiconductor, Inc.
   6 */
   7
   8#include <linux/bitfield.h>
   9#include <linux/bits.h>
  10#include <linux/clk.h>
  11#include <linux/console.h>
  12#include <linux/delay.h>
  13#include <linux/dma-mapping.h>
  14#include <linux/dmaengine.h>
  15#include <linux/dmapool.h>
  16#include <linux/io.h>
  17#include <linux/iopoll.h>
  18#include <linux/irq.h>
  19#include <linux/module.h>
  20#include <linux/of.h>
 
  21#include <linux/of_dma.h>
  22#include <linux/pinctrl/consumer.h>
  23#include <linux/platform_device.h>
  24#include <linux/pm_runtime.h>
  25#include <linux/serial_core.h>
  26#include <linux/slab.h>
  27#include <linux/tty_flip.h>
  28
  29/* All registers are 8-bit width */
  30#define UARTBDH			0x00
  31#define UARTBDL			0x01
  32#define UARTCR1			0x02
  33#define UARTCR2			0x03
  34#define UARTSR1			0x04
  35#define UARTCR3			0x06
  36#define UARTDR			0x07
  37#define UARTCR4			0x0a
  38#define UARTCR5			0x0b
  39#define UARTMODEM		0x0d
  40#define UARTPFIFO		0x10
  41#define UARTCFIFO		0x11
  42#define UARTSFIFO		0x12
  43#define UARTTWFIFO		0x13
  44#define UARTTCFIFO		0x14
  45#define UARTRWFIFO		0x15
  46
  47#define UARTBDH_LBKDIE		0x80
  48#define UARTBDH_RXEDGIE		0x40
  49#define UARTBDH_SBR_MASK	0x1f
  50
  51#define UARTCR1_LOOPS		0x80
  52#define UARTCR1_RSRC		0x20
  53#define UARTCR1_M		0x10
  54#define UARTCR1_WAKE		0x08
  55#define UARTCR1_ILT		0x04
  56#define UARTCR1_PE		0x02
  57#define UARTCR1_PT		0x01
  58
  59#define UARTCR2_TIE		0x80
  60#define UARTCR2_TCIE		0x40
  61#define UARTCR2_RIE		0x20
  62#define UARTCR2_ILIE		0x10
  63#define UARTCR2_TE		0x08
  64#define UARTCR2_RE		0x04
  65#define UARTCR2_RWU		0x02
  66#define UARTCR2_SBK		0x01
  67
  68#define UARTSR1_TDRE		0x80
  69#define UARTSR1_TC		0x40
  70#define UARTSR1_RDRF		0x20
  71#define UARTSR1_IDLE		0x10
  72#define UARTSR1_OR		0x08
  73#define UARTSR1_NF		0x04
  74#define UARTSR1_FE		0x02
  75#define UARTSR1_PE		0x01
  76
  77#define UARTCR3_R8		0x80
  78#define UARTCR3_T8		0x40
  79#define UARTCR3_TXDIR		0x20
  80#define UARTCR3_TXINV		0x10
  81#define UARTCR3_ORIE		0x08
  82#define UARTCR3_NEIE		0x04
  83#define UARTCR3_FEIE		0x02
  84#define UARTCR3_PEIE		0x01
  85
  86#define UARTCR4_MAEN1		0x80
  87#define UARTCR4_MAEN2		0x40
  88#define UARTCR4_M10		0x20
  89#define UARTCR4_BRFA_MASK	0x1f
  90#define UARTCR4_BRFA_OFF	0
  91
  92#define UARTCR5_TDMAS		0x80
  93#define UARTCR5_RDMAS		0x20
  94
  95#define UARTMODEM_RXRTSE	0x08
  96#define UARTMODEM_TXRTSPOL	0x04
  97#define UARTMODEM_TXRTSE	0x02
  98#define UARTMODEM_TXCTSE	0x01
  99
 100#define UARTPFIFO_TXFE		0x80
 101#define UARTPFIFO_FIFOSIZE_MASK	0x7
 102#define UARTPFIFO_TXSIZE_OFF	4
 103#define UARTPFIFO_RXFE		0x08
 104#define UARTPFIFO_RXSIZE_OFF	0
 105
 106#define UARTCFIFO_TXFLUSH	0x80
 107#define UARTCFIFO_RXFLUSH	0x40
 108#define UARTCFIFO_RXOFE		0x04
 109#define UARTCFIFO_TXOFE		0x02
 110#define UARTCFIFO_RXUFE		0x01
 111
 112#define UARTSFIFO_TXEMPT	0x80
 113#define UARTSFIFO_RXEMPT	0x40
 114#define UARTSFIFO_RXOF		0x04
 115#define UARTSFIFO_TXOF		0x02
 116#define UARTSFIFO_RXUF		0x01
 117
 118/* 32-bit global registers only for i.MX7ULP/i.MX8x
 119 * Used to reset all internal logic and registers, except the Global Register.
 120 */
 121#define UART_GLOBAL		0x8
 122
 123/* 32-bit register definition */
 124#define UARTBAUD		0x00
 125#define UARTSTAT		0x04
 126#define UARTCTRL		0x08
 127#define UARTDATA		0x0C
 128#define UARTMATCH		0x10
 129#define UARTMODIR		0x14
 130#define UARTFIFO		0x18
 131#define UARTWATER		0x1c
 132
 133#define UARTBAUD_MAEN1		0x80000000
 134#define UARTBAUD_MAEN2		0x40000000
 135#define UARTBAUD_M10		0x20000000
 136#define UARTBAUD_TDMAE		0x00800000
 137#define UARTBAUD_RDMAE		0x00200000
 138#define UARTBAUD_MATCFG		0x00400000
 139#define UARTBAUD_BOTHEDGE	0x00020000
 140#define UARTBAUD_RESYNCDIS	0x00010000
 141#define UARTBAUD_LBKDIE		0x00008000
 142#define UARTBAUD_RXEDGIE	0x00004000
 143#define UARTBAUD_SBNS		0x00002000
 144#define UARTBAUD_SBR		0x00000000
 145#define UARTBAUD_SBR_MASK	0x1fff
 146#define UARTBAUD_OSR_MASK       0x1f
 147#define UARTBAUD_OSR_SHIFT      24
 148
 149#define UARTSTAT_LBKDIF		0x80000000
 150#define UARTSTAT_RXEDGIF	0x40000000
 151#define UARTSTAT_MSBF		0x20000000
 152#define UARTSTAT_RXINV		0x10000000
 153#define UARTSTAT_RWUID		0x08000000
 154#define UARTSTAT_BRK13		0x04000000
 155#define UARTSTAT_LBKDE		0x02000000
 156#define UARTSTAT_RAF		0x01000000
 157#define UARTSTAT_TDRE		0x00800000
 158#define UARTSTAT_TC		0x00400000
 159#define UARTSTAT_RDRF		0x00200000
 160#define UARTSTAT_IDLE		0x00100000
 161#define UARTSTAT_OR		0x00080000
 162#define UARTSTAT_NF		0x00040000
 163#define UARTSTAT_FE		0x00020000
 164#define UARTSTAT_PE		0x00010000
 165#define UARTSTAT_MA1F		0x00008000
 166#define UARTSTAT_M21F		0x00004000
 167
 168#define UARTCTRL_R8T9		0x80000000
 169#define UARTCTRL_R9T8		0x40000000
 170#define UARTCTRL_TXDIR		0x20000000
 171#define UARTCTRL_TXINV		0x10000000
 172#define UARTCTRL_ORIE		0x08000000
 173#define UARTCTRL_NEIE		0x04000000
 174#define UARTCTRL_FEIE		0x02000000
 175#define UARTCTRL_PEIE		0x01000000
 176#define UARTCTRL_TIE		0x00800000
 177#define UARTCTRL_TCIE		0x00400000
 178#define UARTCTRL_RIE		0x00200000
 179#define UARTCTRL_ILIE		0x00100000
 180#define UARTCTRL_TE		0x00080000
 181#define UARTCTRL_RE		0x00040000
 182#define UARTCTRL_RWU		0x00020000
 183#define UARTCTRL_SBK		0x00010000
 184#define UARTCTRL_MA1IE		0x00008000
 185#define UARTCTRL_MA2IE		0x00004000
 186#define UARTCTRL_IDLECFG	GENMASK(10, 8)
 187#define UARTCTRL_LOOPS		0x00000080
 188#define UARTCTRL_DOZEEN		0x00000040
 189#define UARTCTRL_RSRC		0x00000020
 190#define UARTCTRL_M		0x00000010
 191#define UARTCTRL_WAKE		0x00000008
 192#define UARTCTRL_ILT		0x00000004
 193#define UARTCTRL_PE		0x00000002
 194#define UARTCTRL_PT		0x00000001
 195
 196#define UARTDATA_NOISY		0x00008000
 197#define UARTDATA_PARITYE	0x00004000
 198#define UARTDATA_FRETSC		0x00002000
 199#define UARTDATA_RXEMPT		0x00001000
 200#define UARTDATA_IDLINE		0x00000800
 201#define UARTDATA_MASK		0x3ff
 202
 203#define UARTMODIR_IREN		0x00020000
 204#define UARTMODIR_RTSWATER	GENMASK(10, 8)
 205#define UARTMODIR_TXCTSSRC	0x00000020
 206#define UARTMODIR_TXCTSC	0x00000010
 207#define UARTMODIR_RXRTSE	0x00000008
 208#define UARTMODIR_TXRTSPOL	0x00000004
 209#define UARTMODIR_TXRTSE	0x00000002
 210#define UARTMODIR_TXCTSE	0x00000001
 211
 212#define UARTFIFO_TXEMPT		0x00800000
 213#define UARTFIFO_RXEMPT		0x00400000
 214#define UARTFIFO_TXOF		0x00020000
 215#define UARTFIFO_RXUF		0x00010000
 216#define UARTFIFO_TXFLUSH	0x00008000
 217#define UARTFIFO_RXFLUSH	0x00004000
 218#define UARTFIFO_RXIDEN	GENMASK(12, 10)
 219#define UARTFIFO_TXOFE		0x00000200
 220#define UARTFIFO_RXUFE		0x00000100
 221#define UARTFIFO_TXFE		0x00000080
 222#define UARTFIFO_FIFOSIZE_MASK	0x7
 223#define UARTFIFO_TXSIZE_OFF	4
 224#define UARTFIFO_RXFE		0x00000008
 225#define UARTFIFO_RXSIZE_OFF	0
 226#define UARTFIFO_DEPTH(x)	(0x1 << ((x) ? ((x) + 1) : 0))
 227
 228#define UARTWATER_COUNT_MASK	0xff
 229#define UARTWATER_TXCNT_OFF	8
 230#define UARTWATER_RXCNT_OFF	24
 231#define UARTWATER_WATER_MASK	0xff
 232#define UARTWATER_TXWATER_OFF	0
 233#define UARTWATER_RXWATER_OFF	16
 234
 235#define UART_GLOBAL_RST	0x2
 236#define GLOBAL_RST_MIN_US	20
 237#define GLOBAL_RST_MAX_US	40
 238
 239/* Rx DMA timeout in ms, which is used to calculate Rx ring buffer size */
 240#define DMA_RX_TIMEOUT		(10)
 241#define DMA_RX_IDLE_CHARS	8
 242#define UART_AUTOSUSPEND_TIMEOUT	3000
 243
 244#define DRIVER_NAME	"fsl-lpuart"
 245#define DEV_NAME	"ttyLP"
 246#define UART_NR		8
 247
 248/* IMX lpuart has four extra unused regs located at the beginning */
 249#define IMX_REG_OFF	0x10
 250
 251enum lpuart_type {
 252	VF610_LPUART,
 253	LS1021A_LPUART,
 254	LS1028A_LPUART,
 255	IMX7ULP_LPUART,
 256	IMX8ULP_LPUART,
 257	IMX8QXP_LPUART,
 258	IMXRT1050_LPUART,
 259};
 260
 261struct lpuart_port {
 262	struct uart_port	port;
 263	enum lpuart_type	devtype;
 264	struct clk		*ipg_clk;
 265	struct clk		*baud_clk;
 266	unsigned int		txfifo_size;
 267	unsigned int		rxfifo_size;
 268
 269	u8			rx_watermark;
 270	bool			lpuart_dma_tx_use;
 271	bool			lpuart_dma_rx_use;
 272	struct dma_chan		*dma_tx_chan;
 273	struct dma_chan		*dma_rx_chan;
 274	struct dma_async_tx_descriptor  *dma_tx_desc;
 275	struct dma_async_tx_descriptor  *dma_rx_desc;
 276	dma_cookie_t		dma_tx_cookie;
 277	dma_cookie_t		dma_rx_cookie;
 278	unsigned int		dma_tx_bytes;
 279	unsigned int		dma_rx_bytes;
 280	bool			dma_tx_in_progress;
 281	unsigned int		dma_rx_timeout;
 282	struct timer_list	lpuart_timer;
 283	struct scatterlist	rx_sgl, tx_sgl[2];
 284	struct circ_buf		rx_ring;
 285	int			rx_dma_rng_buf_len;
 286	int                     last_residue;
 287	unsigned int		dma_tx_nents;
 288	wait_queue_head_t	dma_wait;
 289	bool			is_cs7; /* Set to true when character size is 7 */
 290					/* and the parity is enabled		*/
 291	bool			dma_idle_int;
 292};
 293
 294struct lpuart_soc_data {
 295	enum lpuart_type devtype;
 296	char iotype;
 297	u8 reg_off;
 298	u8 rx_watermark;
 299};
 300
 301static const struct lpuart_soc_data vf_data = {
 302	.devtype = VF610_LPUART,
 303	.iotype = UPIO_MEM,
 304	.rx_watermark = 1,
 305};
 306
 307static const struct lpuart_soc_data ls1021a_data = {
 308	.devtype = LS1021A_LPUART,
 309	.iotype = UPIO_MEM32BE,
 310	.rx_watermark = 1,
 311};
 312
 313static const struct lpuart_soc_data ls1028a_data = {
 314	.devtype = LS1028A_LPUART,
 315	.iotype = UPIO_MEM32,
 316	.rx_watermark = 0,
 317};
 318
 319static struct lpuart_soc_data imx7ulp_data = {
 320	.devtype = IMX7ULP_LPUART,
 321	.iotype = UPIO_MEM32,
 322	.reg_off = IMX_REG_OFF,
 323	.rx_watermark = 1,
 324};
 325
 326static struct lpuart_soc_data imx8ulp_data = {
 327	.devtype = IMX8ULP_LPUART,
 328	.iotype = UPIO_MEM32,
 329	.reg_off = IMX_REG_OFF,
 330	.rx_watermark = 3,
 331};
 332
 333static struct lpuart_soc_data imx8qxp_data = {
 334	.devtype = IMX8QXP_LPUART,
 335	.iotype = UPIO_MEM32,
 336	.reg_off = IMX_REG_OFF,
 337	.rx_watermark = 7, /* A lower watermark is ideal for low baud rates. */
 338};
 339static struct lpuart_soc_data imxrt1050_data = {
 340	.devtype = IMXRT1050_LPUART,
 341	.iotype = UPIO_MEM32,
 342	.reg_off = IMX_REG_OFF,
 343	.rx_watermark = 1,
 344};
 345
 346static const struct of_device_id lpuart_dt_ids[] = {
 347	{ .compatible = "fsl,vf610-lpuart",	.data = &vf_data, },
 348	{ .compatible = "fsl,ls1021a-lpuart",	.data = &ls1021a_data, },
 349	{ .compatible = "fsl,ls1028a-lpuart",	.data = &ls1028a_data, },
 350	{ .compatible = "fsl,imx7ulp-lpuart",	.data = &imx7ulp_data, },
 351	{ .compatible = "fsl,imx8ulp-lpuart",	.data = &imx8ulp_data, },
 352	{ .compatible = "fsl,imx8qxp-lpuart",	.data = &imx8qxp_data, },
 353	{ .compatible = "fsl,imxrt1050-lpuart",	.data = &imxrt1050_data},
 354	{ /* sentinel */ }
 355};
 356MODULE_DEVICE_TABLE(of, lpuart_dt_ids);
 357
 358/* Forward declare this for the dma callbacks*/
 359static void lpuart_dma_tx_complete(void *arg);
 360
 361static inline bool is_layerscape_lpuart(struct lpuart_port *sport)
 362{
 363	return (sport->devtype == LS1021A_LPUART ||
 364		sport->devtype == LS1028A_LPUART);
 365}
 366
 367static inline bool is_imx7ulp_lpuart(struct lpuart_port *sport)
 368{
 369	return sport->devtype == IMX7ULP_LPUART;
 370}
 371
 372static inline bool is_imx8ulp_lpuart(struct lpuart_port *sport)
 373{
 374	return sport->devtype == IMX8ULP_LPUART;
 375}
 376
 377static inline bool is_imx8qxp_lpuart(struct lpuart_port *sport)
 378{
 379	return sport->devtype == IMX8QXP_LPUART;
 380}
 381
 382static inline u32 lpuart32_read(struct uart_port *port, u32 off)
 383{
 384	switch (port->iotype) {
 385	case UPIO_MEM32:
 386		return readl(port->membase + off);
 387	case UPIO_MEM32BE:
 388		return ioread32be(port->membase + off);
 389	default:
 390		return 0;
 391	}
 392}
 393
 394static inline void lpuart32_write(struct uart_port *port, u32 val,
 395				  u32 off)
 396{
 397	switch (port->iotype) {
 398	case UPIO_MEM32:
 399		writel(val, port->membase + off);
 400		break;
 401	case UPIO_MEM32BE:
 402		iowrite32be(val, port->membase + off);
 403		break;
 404	}
 405}
 406
 407static int __lpuart_enable_clks(struct lpuart_port *sport, bool is_en)
 408{
 409	int ret = 0;
 410
 411	if (is_en) {
 412		ret = clk_prepare_enable(sport->ipg_clk);
 413		if (ret)
 414			return ret;
 415
 416		ret = clk_prepare_enable(sport->baud_clk);
 417		if (ret) {
 418			clk_disable_unprepare(sport->ipg_clk);
 419			return ret;
 420		}
 421	} else {
 422		clk_disable_unprepare(sport->baud_clk);
 423		clk_disable_unprepare(sport->ipg_clk);
 424	}
 425
 426	return 0;
 427}
 428
 429static unsigned int lpuart_get_baud_clk_rate(struct lpuart_port *sport)
 430{
 431	if (is_imx8qxp_lpuart(sport))
 432		return clk_get_rate(sport->baud_clk);
 433
 434	return clk_get_rate(sport->ipg_clk);
 435}
 436
 437#define lpuart_enable_clks(x)	__lpuart_enable_clks(x, true)
 438#define lpuart_disable_clks(x)	__lpuart_enable_clks(x, false)
 439
 440static void lpuart_stop_tx(struct uart_port *port)
 441{
 442	unsigned char temp;
 443
 444	temp = readb(port->membase + UARTCR2);
 445	temp &= ~(UARTCR2_TIE | UARTCR2_TCIE);
 446	writeb(temp, port->membase + UARTCR2);
 447}
 448
 449static void lpuart32_stop_tx(struct uart_port *port)
 450{
 451	unsigned long temp;
 452
 453	temp = lpuart32_read(port, UARTCTRL);
 454	temp &= ~(UARTCTRL_TIE | UARTCTRL_TCIE);
 455	lpuart32_write(port, temp, UARTCTRL);
 456}
 457
 458static void lpuart_stop_rx(struct uart_port *port)
 459{
 460	unsigned char temp;
 461
 462	temp = readb(port->membase + UARTCR2);
 463	writeb(temp & ~UARTCR2_RE, port->membase + UARTCR2);
 464}
 465
 466static void lpuart32_stop_rx(struct uart_port *port)
 467{
 468	unsigned long temp;
 469
 470	temp = lpuart32_read(port, UARTCTRL);
 471	lpuart32_write(port, temp & ~UARTCTRL_RE, UARTCTRL);
 472}
 473
 474static void lpuart_dma_tx(struct lpuart_port *sport)
 475{
 476	struct circ_buf *xmit = &sport->port.state->xmit;
 477	struct scatterlist *sgl = sport->tx_sgl;
 478	struct device *dev = sport->port.dev;
 479	struct dma_chan *chan = sport->dma_tx_chan;
 480	int ret;
 481
 482	if (sport->dma_tx_in_progress)
 483		return;
 484
 485	sport->dma_tx_bytes = uart_circ_chars_pending(xmit);
 486
 487	if (xmit->tail < xmit->head || xmit->head == 0) {
 488		sport->dma_tx_nents = 1;
 489		sg_init_one(sgl, xmit->buf + xmit->tail, sport->dma_tx_bytes);
 490	} else {
 491		sport->dma_tx_nents = 2;
 492		sg_init_table(sgl, 2);
 493		sg_set_buf(sgl, xmit->buf + xmit->tail,
 494				UART_XMIT_SIZE - xmit->tail);
 495		sg_set_buf(sgl + 1, xmit->buf, xmit->head);
 496	}
 497
 498	ret = dma_map_sg(chan->device->dev, sgl, sport->dma_tx_nents,
 499			 DMA_TO_DEVICE);
 500	if (!ret) {
 501		dev_err(dev, "DMA mapping error for TX.\n");
 502		return;
 503	}
 504
 505	sport->dma_tx_desc = dmaengine_prep_slave_sg(chan, sgl,
 506					ret, DMA_MEM_TO_DEV,
 507					DMA_PREP_INTERRUPT);
 508	if (!sport->dma_tx_desc) {
 509		dma_unmap_sg(chan->device->dev, sgl, sport->dma_tx_nents,
 510			      DMA_TO_DEVICE);
 511		dev_err(dev, "Cannot prepare TX slave DMA!\n");
 512		return;
 513	}
 514
 515	sport->dma_tx_desc->callback = lpuart_dma_tx_complete;
 516	sport->dma_tx_desc->callback_param = sport;
 517	sport->dma_tx_in_progress = true;
 518	sport->dma_tx_cookie = dmaengine_submit(sport->dma_tx_desc);
 519	dma_async_issue_pending(chan);
 520}
 521
 522static bool lpuart_stopped_or_empty(struct uart_port *port)
 523{
 524	return uart_circ_empty(&port->state->xmit) || uart_tx_stopped(port);
 525}
 526
 527static void lpuart_dma_tx_complete(void *arg)
 528{
 529	struct lpuart_port *sport = arg;
 530	struct scatterlist *sgl = &sport->tx_sgl[0];
 531	struct circ_buf *xmit = &sport->port.state->xmit;
 532	struct dma_chan *chan = sport->dma_tx_chan;
 533	unsigned long flags;
 534
 535	uart_port_lock_irqsave(&sport->port, &flags);
 536	if (!sport->dma_tx_in_progress) {
 537		uart_port_unlock_irqrestore(&sport->port, flags);
 538		return;
 539	}
 540
 541	dma_unmap_sg(chan->device->dev, sgl, sport->dma_tx_nents,
 542		     DMA_TO_DEVICE);
 543
 544	uart_xmit_advance(&sport->port, sport->dma_tx_bytes);
 545	sport->dma_tx_in_progress = false;
 546	uart_port_unlock_irqrestore(&sport->port, flags);
 547
 548	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 549		uart_write_wakeup(&sport->port);
 550
 551	if (waitqueue_active(&sport->dma_wait)) {
 552		wake_up(&sport->dma_wait);
 553		return;
 554	}
 555
 556	uart_port_lock_irqsave(&sport->port, &flags);
 557
 558	if (!lpuart_stopped_or_empty(&sport->port))
 559		lpuart_dma_tx(sport);
 560
 561	uart_port_unlock_irqrestore(&sport->port, flags);
 562}
 563
 564static dma_addr_t lpuart_dma_datareg_addr(struct lpuart_port *sport)
 565{
 566	switch (sport->port.iotype) {
 567	case UPIO_MEM32:
 568		return sport->port.mapbase + UARTDATA;
 569	case UPIO_MEM32BE:
 570		return sport->port.mapbase + UARTDATA + sizeof(u32) - 1;
 571	}
 572	return sport->port.mapbase + UARTDR;
 573}
 574
 575static int lpuart_dma_tx_request(struct uart_port *port)
 576{
 577	struct lpuart_port *sport = container_of(port,
 578					struct lpuart_port, port);
 579	struct dma_slave_config dma_tx_sconfig = {};
 580	int ret;
 581
 582	dma_tx_sconfig.dst_addr = lpuart_dma_datareg_addr(sport);
 583	dma_tx_sconfig.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
 584	dma_tx_sconfig.dst_maxburst = 1;
 585	dma_tx_sconfig.direction = DMA_MEM_TO_DEV;
 586	ret = dmaengine_slave_config(sport->dma_tx_chan, &dma_tx_sconfig);
 587
 588	if (ret) {
 589		dev_err(sport->port.dev,
 590				"DMA slave config failed, err = %d\n", ret);
 591		return ret;
 592	}
 593
 594	return 0;
 595}
 596
 597static bool lpuart_is_32(struct lpuart_port *sport)
 598{
 599	return sport->port.iotype == UPIO_MEM32 ||
 600	       sport->port.iotype ==  UPIO_MEM32BE;
 601}
 602
 603static void lpuart_flush_buffer(struct uart_port *port)
 604{
 605	struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
 606	struct dma_chan *chan = sport->dma_tx_chan;
 607	u32 val;
 608
 609	if (sport->lpuart_dma_tx_use) {
 610		if (sport->dma_tx_in_progress) {
 611			dma_unmap_sg(chan->device->dev, &sport->tx_sgl[0],
 612				sport->dma_tx_nents, DMA_TO_DEVICE);
 613			sport->dma_tx_in_progress = false;
 614		}
 615		dmaengine_terminate_async(chan);
 616	}
 617
 618	if (lpuart_is_32(sport)) {
 619		val = lpuart32_read(&sport->port, UARTFIFO);
 620		val |= UARTFIFO_TXFLUSH | UARTFIFO_RXFLUSH;
 621		lpuart32_write(&sport->port, val, UARTFIFO);
 622	} else {
 623		val = readb(sport->port.membase + UARTCFIFO);
 624		val |= UARTCFIFO_TXFLUSH | UARTCFIFO_RXFLUSH;
 625		writeb(val, sport->port.membase + UARTCFIFO);
 626	}
 627}
 628
 629static void lpuart_wait_bit_set(struct uart_port *port, unsigned int offset,
 630				u8 bit)
 631{
 632	while (!(readb(port->membase + offset) & bit))
 633		cpu_relax();
 634}
 635
 636static void lpuart32_wait_bit_set(struct uart_port *port, unsigned int offset,
 637				  u32 bit)
 638{
 639	while (!(lpuart32_read(port, offset) & bit))
 640		cpu_relax();
 641}
 642
 643#if defined(CONFIG_CONSOLE_POLL)
 644
 645static int lpuart_poll_init(struct uart_port *port)
 646{
 647	struct lpuart_port *sport = container_of(port,
 648					struct lpuart_port, port);
 649	unsigned long flags;
 650	unsigned char temp;
 651
 652	sport->port.fifosize = 0;
 653
 654	uart_port_lock_irqsave(&sport->port, &flags);
 655	/* Disable Rx & Tx */
 656	writeb(0, sport->port.membase + UARTCR2);
 657
 658	temp = readb(sport->port.membase + UARTPFIFO);
 659	/* Enable Rx and Tx FIFO */
 660	writeb(temp | UARTPFIFO_RXFE | UARTPFIFO_TXFE,
 661			sport->port.membase + UARTPFIFO);
 662
 663	/* flush Tx and Rx FIFO */
 664	writeb(UARTCFIFO_TXFLUSH | UARTCFIFO_RXFLUSH,
 665			sport->port.membase + UARTCFIFO);
 666
 667	/* explicitly clear RDRF */
 668	if (readb(sport->port.membase + UARTSR1) & UARTSR1_RDRF) {
 669		readb(sport->port.membase + UARTDR);
 670		writeb(UARTSFIFO_RXUF, sport->port.membase + UARTSFIFO);
 671	}
 672
 673	writeb(0, sport->port.membase + UARTTWFIFO);
 674	writeb(1, sport->port.membase + UARTRWFIFO);
 675
 676	/* Enable Rx and Tx */
 677	writeb(UARTCR2_RE | UARTCR2_TE, sport->port.membase + UARTCR2);
 678	uart_port_unlock_irqrestore(&sport->port, flags);
 679
 680	return 0;
 681}
 682
 683static void lpuart_poll_put_char(struct uart_port *port, unsigned char c)
 684{
 685	/* drain */
 686	lpuart_wait_bit_set(port, UARTSR1, UARTSR1_TDRE);
 687	writeb(c, port->membase + UARTDR);
 688}
 689
 690static int lpuart_poll_get_char(struct uart_port *port)
 691{
 692	if (!(readb(port->membase + UARTSR1) & UARTSR1_RDRF))
 693		return NO_POLL_CHAR;
 694
 695	return readb(port->membase + UARTDR);
 696}
 697
 698static int lpuart32_poll_init(struct uart_port *port)
 699{
 700	unsigned long flags;
 701	struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
 702	u32 temp;
 703
 704	sport->port.fifosize = 0;
 705
 706	uart_port_lock_irqsave(&sport->port, &flags);
 707
 708	/* Disable Rx & Tx */
 709	lpuart32_write(&sport->port, 0, UARTCTRL);
 710
 711	temp = lpuart32_read(&sport->port, UARTFIFO);
 712
 713	/* Enable Rx and Tx FIFO */
 714	lpuart32_write(&sport->port, temp | UARTFIFO_RXFE | UARTFIFO_TXFE, UARTFIFO);
 715
 716	/* flush Tx and Rx FIFO */
 717	lpuart32_write(&sport->port, UARTFIFO_TXFLUSH | UARTFIFO_RXFLUSH, UARTFIFO);
 718
 719	/* explicitly clear RDRF */
 720	if (lpuart32_read(&sport->port, UARTSTAT) & UARTSTAT_RDRF) {
 721		lpuart32_read(&sport->port, UARTDATA);
 722		lpuart32_write(&sport->port, UARTFIFO_RXUF, UARTFIFO);
 723	}
 724
 725	/* Enable Rx and Tx */
 726	lpuart32_write(&sport->port, UARTCTRL_RE | UARTCTRL_TE, UARTCTRL);
 727	uart_port_unlock_irqrestore(&sport->port, flags);
 728
 729	return 0;
 730}
 731
 732static void lpuart32_poll_put_char(struct uart_port *port, unsigned char c)
 733{
 734	lpuart32_wait_bit_set(port, UARTSTAT, UARTSTAT_TDRE);
 735	lpuart32_write(port, c, UARTDATA);
 736}
 737
 738static int lpuart32_poll_get_char(struct uart_port *port)
 739{
 740	if (!(lpuart32_read(port, UARTWATER) >> UARTWATER_RXCNT_OFF))
 741		return NO_POLL_CHAR;
 742
 743	return lpuart32_read(port, UARTDATA);
 744}
 745#endif
 746
 747static inline void lpuart_transmit_buffer(struct lpuart_port *sport)
 748{
 749	struct uart_port *port = &sport->port;
 750	u8 ch;
 751
 752	uart_port_tx(port, ch,
 753		readb(port->membase + UARTTCFIFO) < sport->txfifo_size,
 754		writeb(ch, port->membase + UARTDR));
 755}
 756
 757static inline void lpuart32_transmit_buffer(struct lpuart_port *sport)
 758{
 759	struct circ_buf *xmit = &sport->port.state->xmit;
 760	unsigned long txcnt;
 761
 762	if (sport->port.x_char) {
 763		lpuart32_write(&sport->port, sport->port.x_char, UARTDATA);
 764		sport->port.icount.tx++;
 765		sport->port.x_char = 0;
 766		return;
 767	}
 768
 769	if (lpuart_stopped_or_empty(&sport->port)) {
 770		lpuart32_stop_tx(&sport->port);
 771		return;
 772	}
 773
 774	txcnt = lpuart32_read(&sport->port, UARTWATER);
 775	txcnt = txcnt >> UARTWATER_TXCNT_OFF;
 776	txcnt &= UARTWATER_COUNT_MASK;
 777	while (!uart_circ_empty(xmit) && (txcnt < sport->txfifo_size)) {
 778		lpuart32_write(&sport->port, xmit->buf[xmit->tail], UARTDATA);
 779		uart_xmit_advance(&sport->port, 1);
 780		txcnt = lpuart32_read(&sport->port, UARTWATER);
 781		txcnt = txcnt >> UARTWATER_TXCNT_OFF;
 782		txcnt &= UARTWATER_COUNT_MASK;
 783	}
 784
 785	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 786		uart_write_wakeup(&sport->port);
 787
 788	if (uart_circ_empty(xmit))
 789		lpuart32_stop_tx(&sport->port);
 790}
 791
 792static void lpuart_start_tx(struct uart_port *port)
 793{
 794	struct lpuart_port *sport = container_of(port,
 795			struct lpuart_port, port);
 796	unsigned char temp;
 797
 798	temp = readb(port->membase + UARTCR2);
 799	writeb(temp | UARTCR2_TIE, port->membase + UARTCR2);
 800
 801	if (sport->lpuart_dma_tx_use) {
 802		if (!lpuart_stopped_or_empty(port))
 803			lpuart_dma_tx(sport);
 804	} else {
 805		if (readb(port->membase + UARTSR1) & UARTSR1_TDRE)
 806			lpuart_transmit_buffer(sport);
 807	}
 808}
 809
 810static void lpuart32_start_tx(struct uart_port *port)
 811{
 812	struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
 813	unsigned long temp;
 814
 815	if (sport->lpuart_dma_tx_use) {
 816		if (!lpuart_stopped_or_empty(port))
 817			lpuart_dma_tx(sport);
 818	} else {
 819		temp = lpuart32_read(port, UARTCTRL);
 820		lpuart32_write(port, temp | UARTCTRL_TIE, UARTCTRL);
 821
 822		if (lpuart32_read(port, UARTSTAT) & UARTSTAT_TDRE)
 823			lpuart32_transmit_buffer(sport);
 824	}
 825}
 826
 827static void
 828lpuart_uart_pm(struct uart_port *port, unsigned int state, unsigned int oldstate)
 829{
 830	switch (state) {
 831	case UART_PM_STATE_OFF:
 832		pm_runtime_mark_last_busy(port->dev);
 833		pm_runtime_put_autosuspend(port->dev);
 834		break;
 835	default:
 836		pm_runtime_get_sync(port->dev);
 837		break;
 838	}
 839}
 840
 841/* return TIOCSER_TEMT when transmitter is not busy */
 842static unsigned int lpuart_tx_empty(struct uart_port *port)
 843{
 844	struct lpuart_port *sport = container_of(port,
 845			struct lpuart_port, port);
 846	unsigned char sr1 = readb(port->membase + UARTSR1);
 847	unsigned char sfifo = readb(port->membase + UARTSFIFO);
 848
 849	if (sport->dma_tx_in_progress)
 850		return 0;
 851
 852	if (sr1 & UARTSR1_TC && sfifo & UARTSFIFO_TXEMPT)
 853		return TIOCSER_TEMT;
 854
 855	return 0;
 856}
 857
 858static unsigned int lpuart32_tx_empty(struct uart_port *port)
 859{
 860	struct lpuart_port *sport = container_of(port,
 861			struct lpuart_port, port);
 862	unsigned long stat = lpuart32_read(port, UARTSTAT);
 863	unsigned long sfifo = lpuart32_read(port, UARTFIFO);
 864	unsigned long ctrl = lpuart32_read(port, UARTCTRL);
 865
 866	if (sport->dma_tx_in_progress)
 867		return 0;
 868
 869	/*
 870	 * LPUART Transmission Complete Flag may never be set while queuing a break
 871	 * character, so avoid checking for transmission complete when UARTCTRL_SBK
 872	 * is asserted.
 873	 */
 874	if ((stat & UARTSTAT_TC && sfifo & UARTFIFO_TXEMPT) || ctrl & UARTCTRL_SBK)
 875		return TIOCSER_TEMT;
 876
 877	return 0;
 878}
 879
 880static void lpuart_txint(struct lpuart_port *sport)
 881{
 882	uart_port_lock(&sport->port);
 883	lpuart_transmit_buffer(sport);
 884	uart_port_unlock(&sport->port);
 885}
 886
 887static void lpuart_rxint(struct lpuart_port *sport)
 888{
 889	unsigned int flg, ignored = 0, overrun = 0;
 890	struct tty_port *port = &sport->port.state->port;
 891	unsigned char rx, sr;
 892
 893	uart_port_lock(&sport->port);
 894
 895	while (!(readb(sport->port.membase + UARTSFIFO) & UARTSFIFO_RXEMPT)) {
 896		flg = TTY_NORMAL;
 897		sport->port.icount.rx++;
 898		/*
 899		 * to clear the FE, OR, NF, FE, PE flags,
 900		 * read SR1 then read DR
 901		 */
 902		sr = readb(sport->port.membase + UARTSR1);
 903		rx = readb(sport->port.membase + UARTDR);
 904
 905		if (uart_prepare_sysrq_char(&sport->port, rx))
 906			continue;
 907
 908		if (sr & (UARTSR1_PE | UARTSR1_OR | UARTSR1_FE)) {
 909			if (sr & UARTSR1_PE)
 910				sport->port.icount.parity++;
 911			else if (sr & UARTSR1_FE)
 912				sport->port.icount.frame++;
 913
 914			if (sr & UARTSR1_OR)
 915				overrun++;
 916
 917			if (sr & sport->port.ignore_status_mask) {
 918				if (++ignored > 100)
 919					goto out;
 920				continue;
 921			}
 922
 923			sr &= sport->port.read_status_mask;
 924
 925			if (sr & UARTSR1_PE)
 926				flg = TTY_PARITY;
 927			else if (sr & UARTSR1_FE)
 928				flg = TTY_FRAME;
 929
 930			if (sr & UARTSR1_OR)
 931				flg = TTY_OVERRUN;
 932
 933			sport->port.sysrq = 0;
 934		}
 935
 936		if (tty_insert_flip_char(port, rx, flg) == 0)
 937			sport->port.icount.buf_overrun++;
 938	}
 939
 940out:
 941	if (overrun) {
 942		sport->port.icount.overrun += overrun;
 943
 944		/*
 945		 * Overruns cause FIFO pointers to become missaligned.
 946		 * Flushing the receive FIFO reinitializes the pointers.
 947		 */
 948		writeb(UARTCFIFO_RXFLUSH, sport->port.membase + UARTCFIFO);
 949		writeb(UARTSFIFO_RXOF, sport->port.membase + UARTSFIFO);
 950	}
 951
 952	uart_unlock_and_check_sysrq(&sport->port);
 953
 954	tty_flip_buffer_push(port);
 955}
 956
 957static void lpuart32_txint(struct lpuart_port *sport)
 958{
 959	uart_port_lock(&sport->port);
 960	lpuart32_transmit_buffer(sport);
 961	uart_port_unlock(&sport->port);
 962}
 963
 964static void lpuart32_rxint(struct lpuart_port *sport)
 965{
 966	unsigned int flg, ignored = 0;
 967	struct tty_port *port = &sport->port.state->port;
 968	unsigned long rx, sr;
 969	bool is_break;
 970
 971	uart_port_lock(&sport->port);
 972
 973	while (!(lpuart32_read(&sport->port, UARTFIFO) & UARTFIFO_RXEMPT)) {
 974		flg = TTY_NORMAL;
 975		sport->port.icount.rx++;
 976		/*
 977		 * to clear the FE, OR, NF, FE, PE flags,
 978		 * read STAT then read DATA reg
 979		 */
 980		sr = lpuart32_read(&sport->port, UARTSTAT);
 981		rx = lpuart32_read(&sport->port, UARTDATA);
 982		rx &= UARTDATA_MASK;
 983
 984		/*
 985		 * The LPUART can't distinguish between a break and a framing error,
 986		 * thus we assume it is a break if the received data is zero.
 987		 */
 988		is_break = (sr & UARTSTAT_FE) && !rx;
 989
 990		if (is_break && uart_handle_break(&sport->port))
 991			continue;
 992
 993		if (uart_prepare_sysrq_char(&sport->port, rx))
 994			continue;
 995
 996		if (sr & (UARTSTAT_PE | UARTSTAT_OR | UARTSTAT_FE)) {
 997			if (sr & UARTSTAT_PE) {
 998				sport->port.icount.parity++;
 999			} else if (sr & UARTSTAT_FE) {
1000				if (is_break)
1001					sport->port.icount.brk++;
1002				else
1003					sport->port.icount.frame++;
1004			}
1005
1006			if (sr & UARTSTAT_OR)
1007				sport->port.icount.overrun++;
1008
1009			if (sr & sport->port.ignore_status_mask) {
1010				if (++ignored > 100)
1011					goto out;
1012				continue;
1013			}
1014
1015			sr &= sport->port.read_status_mask;
1016
1017			if (sr & UARTSTAT_PE) {
1018				flg = TTY_PARITY;
1019			} else if (sr & UARTSTAT_FE) {
1020				if (is_break)
1021					flg = TTY_BREAK;
1022				else
1023					flg = TTY_FRAME;
1024			}
1025
1026			if (sr & UARTSTAT_OR)
1027				flg = TTY_OVERRUN;
1028		}
1029
1030		if (sport->is_cs7)
1031			rx &= 0x7F;
1032
1033		if (tty_insert_flip_char(port, rx, flg) == 0)
1034			sport->port.icount.buf_overrun++;
1035	}
1036
1037out:
1038	uart_unlock_and_check_sysrq(&sport->port);
1039
1040	tty_flip_buffer_push(port);
1041}
1042
1043static irqreturn_t lpuart_int(int irq, void *dev_id)
1044{
1045	struct lpuart_port *sport = dev_id;
1046	unsigned char sts;
1047
1048	sts = readb(sport->port.membase + UARTSR1);
1049
1050	/* SysRq, using dma, check for linebreak by framing err. */
1051	if (sts & UARTSR1_FE && sport->lpuart_dma_rx_use) {
1052		readb(sport->port.membase + UARTDR);
1053		uart_handle_break(&sport->port);
1054		/* linebreak produces some garbage, removing it */
1055		writeb(UARTCFIFO_RXFLUSH, sport->port.membase + UARTCFIFO);
1056		return IRQ_HANDLED;
1057	}
1058
1059	if (sts & UARTSR1_RDRF && !sport->lpuart_dma_rx_use)
1060		lpuart_rxint(sport);
1061
1062	if (sts & UARTSR1_TDRE && !sport->lpuart_dma_tx_use)
1063		lpuart_txint(sport);
1064
1065	return IRQ_HANDLED;
1066}
1067
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1068static inline void lpuart_handle_sysrq_chars(struct uart_port *port,
1069					     unsigned char *p, int count)
1070{
1071	while (count--) {
1072		if (*p && uart_handle_sysrq_char(port, *p))
1073			return;
1074		p++;
1075	}
1076}
1077
1078static void lpuart_handle_sysrq(struct lpuart_port *sport)
1079{
1080	struct circ_buf *ring = &sport->rx_ring;
1081	int count;
1082
1083	if (ring->head < ring->tail) {
1084		count = sport->rx_sgl.length - ring->tail;
1085		lpuart_handle_sysrq_chars(&sport->port,
1086					  ring->buf + ring->tail, count);
1087		ring->tail = 0;
1088	}
1089
1090	if (ring->head > ring->tail) {
1091		count = ring->head - ring->tail;
1092		lpuart_handle_sysrq_chars(&sport->port,
1093					  ring->buf + ring->tail, count);
1094		ring->tail = ring->head;
1095	}
1096}
1097
1098static int lpuart_tty_insert_flip_string(struct tty_port *port,
1099	unsigned char *chars, size_t size, bool is_cs7)
1100{
1101	int i;
1102
1103	if (is_cs7)
1104		for (i = 0; i < size; i++)
1105			chars[i] &= 0x7F;
1106	return tty_insert_flip_string(port, chars, size);
1107}
1108
1109static void lpuart_copy_rx_to_tty(struct lpuart_port *sport)
1110{
1111	struct tty_port *port = &sport->port.state->port;
1112	struct dma_tx_state state;
1113	enum dma_status dmastat;
1114	struct dma_chan *chan = sport->dma_rx_chan;
1115	struct circ_buf *ring = &sport->rx_ring;
1116	unsigned long flags;
1117	int count, copied;
1118
1119	if (lpuart_is_32(sport)) {
1120		unsigned long sr = lpuart32_read(&sport->port, UARTSTAT);
1121
1122		if (sr & (UARTSTAT_PE | UARTSTAT_FE)) {
1123			/* Clear the error flags */
1124			lpuart32_write(&sport->port, sr, UARTSTAT);
1125
1126			if (sr & UARTSTAT_PE)
1127				sport->port.icount.parity++;
1128			else if (sr & UARTSTAT_FE)
1129				sport->port.icount.frame++;
1130		}
1131	} else {
1132		unsigned char sr = readb(sport->port.membase + UARTSR1);
1133
1134		if (sr & (UARTSR1_PE | UARTSR1_FE)) {
1135			unsigned char cr2;
1136
1137			/* Disable receiver during this operation... */
1138			cr2 = readb(sport->port.membase + UARTCR2);
1139			cr2 &= ~UARTCR2_RE;
1140			writeb(cr2, sport->port.membase + UARTCR2);
1141
1142			/* Read DR to clear the error flags */
1143			readb(sport->port.membase + UARTDR);
1144
1145			if (sr & UARTSR1_PE)
1146				sport->port.icount.parity++;
1147			else if (sr & UARTSR1_FE)
1148				sport->port.icount.frame++;
1149			/*
1150			 * At this point parity/framing error is
1151			 * cleared However, since the DMA already read
1152			 * the data register and we had to read it
1153			 * again after reading the status register to
1154			 * properly clear the flags, the FIFO actually
1155			 * underflowed... This requires a clearing of
1156			 * the FIFO...
1157			 */
1158			if (readb(sport->port.membase + UARTSFIFO) &
1159			    UARTSFIFO_RXUF) {
1160				writeb(UARTSFIFO_RXUF,
1161				       sport->port.membase + UARTSFIFO);
1162				writeb(UARTCFIFO_RXFLUSH,
1163				       sport->port.membase + UARTCFIFO);
1164			}
1165
1166			cr2 |= UARTCR2_RE;
1167			writeb(cr2, sport->port.membase + UARTCR2);
1168		}
1169	}
1170
1171	async_tx_ack(sport->dma_rx_desc);
1172
1173	uart_port_lock_irqsave(&sport->port, &flags);
1174
1175	dmastat = dmaengine_tx_status(chan, sport->dma_rx_cookie, &state);
1176	if (dmastat == DMA_ERROR) {
1177		dev_err(sport->port.dev, "Rx DMA transfer failed!\n");
1178		uart_port_unlock_irqrestore(&sport->port, flags);
1179		return;
1180	}
1181
1182	/* CPU claims ownership of RX DMA buffer */
1183	dma_sync_sg_for_cpu(chan->device->dev, &sport->rx_sgl, 1,
1184			    DMA_FROM_DEVICE);
1185
1186	/*
1187	 * ring->head points to the end of data already written by the DMA.
1188	 * ring->tail points to the beginning of data to be read by the
1189	 * framework.
1190	 * The current transfer size should not be larger than the dma buffer
1191	 * length.
1192	 */
1193	ring->head = sport->rx_sgl.length - state.residue;
1194	BUG_ON(ring->head > sport->rx_sgl.length);
1195
1196	/*
1197	 * Silent handling of keys pressed in the sysrq timeframe
1198	 */
1199	if (sport->port.sysrq) {
1200		lpuart_handle_sysrq(sport);
1201		goto exit;
1202	}
1203
1204	/*
1205	 * At this point ring->head may point to the first byte right after the
1206	 * last byte of the dma buffer:
1207	 * 0 <= ring->head <= sport->rx_sgl.length
1208	 *
1209	 * However ring->tail must always points inside the dma buffer:
1210	 * 0 <= ring->tail <= sport->rx_sgl.length - 1
1211	 *
1212	 * Since we use a ring buffer, we have to handle the case
1213	 * where head is lower than tail. In such a case, we first read from
1214	 * tail to the end of the buffer then reset tail.
1215	 */
1216	if (ring->head < ring->tail) {
1217		count = sport->rx_sgl.length - ring->tail;
1218
1219		copied = lpuart_tty_insert_flip_string(port, ring->buf + ring->tail,
1220					count, sport->is_cs7);
1221		if (copied != count)
1222			sport->port.icount.buf_overrun++;
1223		ring->tail = 0;
1224		sport->port.icount.rx += copied;
1225	}
1226
1227	/* Finally we read data from tail to head */
1228	if (ring->tail < ring->head) {
1229		count = ring->head - ring->tail;
1230		copied = lpuart_tty_insert_flip_string(port, ring->buf + ring->tail,
1231					count, sport->is_cs7);
1232		if (copied != count)
1233			sport->port.icount.buf_overrun++;
1234		/* Wrap ring->head if needed */
1235		if (ring->head >= sport->rx_sgl.length)
1236			ring->head = 0;
1237		ring->tail = ring->head;
1238		sport->port.icount.rx += copied;
1239	}
1240
1241	sport->last_residue = state.residue;
1242
1243exit:
1244	dma_sync_sg_for_device(chan->device->dev, &sport->rx_sgl, 1,
1245			       DMA_FROM_DEVICE);
1246
1247	uart_port_unlock_irqrestore(&sport->port, flags);
1248
1249	tty_flip_buffer_push(port);
1250	if (!sport->dma_idle_int)
1251		mod_timer(&sport->lpuart_timer, jiffies + sport->dma_rx_timeout);
1252}
1253
1254static void lpuart_dma_rx_complete(void *arg)
1255{
1256	struct lpuart_port *sport = arg;
1257
1258	lpuart_copy_rx_to_tty(sport);
1259}
1260
1261static void lpuart32_dma_idleint(struct lpuart_port *sport)
1262{
1263	enum dma_status dmastat;
1264	struct dma_chan *chan = sport->dma_rx_chan;
1265	struct circ_buf *ring = &sport->rx_ring;
1266	struct dma_tx_state state;
1267	int count = 0;
1268
1269	dmastat = dmaengine_tx_status(chan, sport->dma_rx_cookie, &state);
1270	if (dmastat == DMA_ERROR) {
1271		dev_err(sport->port.dev, "Rx DMA transfer failed!\n");
1272		return;
1273	}
1274
1275	ring->head = sport->rx_sgl.length - state.residue;
1276	count = CIRC_CNT(ring->head, ring->tail, sport->rx_sgl.length);
1277
1278	/* Check if new data received before copying */
1279	if (count)
1280		lpuart_copy_rx_to_tty(sport);
1281}
1282
1283static irqreturn_t lpuart32_int(int irq, void *dev_id)
1284{
1285	struct lpuart_port *sport = dev_id;
1286	unsigned long sts, rxcount;
1287
1288	sts = lpuart32_read(&sport->port, UARTSTAT);
1289	rxcount = lpuart32_read(&sport->port, UARTWATER);
1290	rxcount = rxcount >> UARTWATER_RXCNT_OFF;
1291
1292	if ((sts & UARTSTAT_RDRF || rxcount > 0) && !sport->lpuart_dma_rx_use)
1293		lpuart32_rxint(sport);
1294
1295	if ((sts & UARTSTAT_TDRE) && !sport->lpuart_dma_tx_use)
1296		lpuart32_txint(sport);
1297
1298	if ((sts & UARTSTAT_IDLE) && sport->lpuart_dma_rx_use && sport->dma_idle_int)
1299		lpuart32_dma_idleint(sport);
1300
1301	lpuart32_write(&sport->port, sts, UARTSTAT);
1302	return IRQ_HANDLED;
1303}
1304
1305/*
1306 * Timer function to simulate the hardware EOP (End Of Package) event.
1307 * The timer callback is to check for new RX data and copy to TTY buffer.
1308 * If no new data are received since last interval, the EOP condition is
1309 * met, complete the DMA transfer by copying the data. Otherwise, just
1310 * restart timer.
1311 */
1312static void lpuart_timer_func(struct timer_list *t)
1313{
1314	struct lpuart_port *sport = from_timer(sport, t, lpuart_timer);
1315	enum dma_status dmastat;
1316	struct dma_chan *chan = sport->dma_rx_chan;
1317	struct circ_buf *ring = &sport->rx_ring;
1318	struct dma_tx_state state;
1319	unsigned long flags;
1320	int count;
1321
1322	dmastat = dmaengine_tx_status(chan, sport->dma_rx_cookie, &state);
1323	if (dmastat == DMA_ERROR) {
1324		dev_err(sport->port.dev, "Rx DMA transfer failed!\n");
1325		return;
1326	}
1327
1328	ring->head = sport->rx_sgl.length - state.residue;
1329	count = CIRC_CNT(ring->head, ring->tail, sport->rx_sgl.length);
1330
1331	/* Check if new data received before copying */
1332	if ((count != 0) && (sport->last_residue == state.residue))
1333		lpuart_copy_rx_to_tty(sport);
1334	else
1335		mod_timer(&sport->lpuart_timer,
1336			  jiffies + sport->dma_rx_timeout);
1337
1338	if (uart_port_trylock_irqsave(&sport->port, &flags)) {
1339		sport->last_residue = state.residue;
1340		uart_port_unlock_irqrestore(&sport->port, flags);
1341	}
1342}
1343
1344static inline int lpuart_start_rx_dma(struct lpuart_port *sport)
1345{
1346	struct dma_slave_config dma_rx_sconfig = {};
1347	struct circ_buf *ring = &sport->rx_ring;
1348	int ret, nent;
1349	struct tty_port *port = &sport->port.state->port;
1350	struct tty_struct *tty = port->tty;
1351	struct ktermios *termios = &tty->termios;
1352	struct dma_chan *chan = sport->dma_rx_chan;
1353	unsigned int bits = tty_get_frame_size(termios->c_cflag);
1354	unsigned int baud = tty_get_baud_rate(tty);
1355
1356	/*
1357	 * Calculate length of one DMA buffer size to keep latency below
1358	 * 10ms at any baud rate.
1359	 */
1360	sport->rx_dma_rng_buf_len = (DMA_RX_TIMEOUT * baud /  bits / 1000) * 2;
1361	sport->rx_dma_rng_buf_len = (1 << fls(sport->rx_dma_rng_buf_len));
1362	sport->rx_dma_rng_buf_len = max_t(int,
1363					  sport->rxfifo_size * 2,
1364					  sport->rx_dma_rng_buf_len);
1365	/*
1366	 * Keep this condition check in case rxfifo_size is unavailable
1367	 * for some SoCs.
1368	 */
1369	if (sport->rx_dma_rng_buf_len < 16)
1370		sport->rx_dma_rng_buf_len = 16;
1371
1372	sport->last_residue = 0;
1373	sport->dma_rx_timeout = max(nsecs_to_jiffies(
1374		sport->port.frame_time * DMA_RX_IDLE_CHARS), 1UL);
1375
1376	ring->buf = kzalloc(sport->rx_dma_rng_buf_len, GFP_ATOMIC);
1377	if (!ring->buf)
1378		return -ENOMEM;
1379
1380	sg_init_one(&sport->rx_sgl, ring->buf, sport->rx_dma_rng_buf_len);
1381	nent = dma_map_sg(chan->device->dev, &sport->rx_sgl, 1,
1382			  DMA_FROM_DEVICE);
1383
1384	if (!nent) {
1385		dev_err(sport->port.dev, "DMA Rx mapping error\n");
1386		return -EINVAL;
1387	}
1388
1389	dma_rx_sconfig.src_addr = lpuart_dma_datareg_addr(sport);
1390	dma_rx_sconfig.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1391	dma_rx_sconfig.src_maxburst = 1;
1392	dma_rx_sconfig.direction = DMA_DEV_TO_MEM;
1393	ret = dmaengine_slave_config(chan, &dma_rx_sconfig);
1394
1395	if (ret < 0) {
1396		dev_err(sport->port.dev,
1397				"DMA Rx slave config failed, err = %d\n", ret);
1398		return ret;
1399	}
1400
1401	sport->dma_rx_desc = dmaengine_prep_dma_cyclic(chan,
1402				 sg_dma_address(&sport->rx_sgl),
1403				 sport->rx_sgl.length,
1404				 sport->rx_sgl.length / 2,
1405				 DMA_DEV_TO_MEM,
1406				 DMA_PREP_INTERRUPT);
1407	if (!sport->dma_rx_desc) {
1408		dev_err(sport->port.dev, "Cannot prepare cyclic DMA\n");
1409		return -EFAULT;
1410	}
1411
1412	sport->dma_rx_desc->callback = lpuart_dma_rx_complete;
1413	sport->dma_rx_desc->callback_param = sport;
1414	sport->dma_rx_cookie = dmaengine_submit(sport->dma_rx_desc);
1415	dma_async_issue_pending(chan);
1416
1417	if (lpuart_is_32(sport)) {
1418		unsigned long temp = lpuart32_read(&sport->port, UARTBAUD);
1419
1420		lpuart32_write(&sport->port, temp | UARTBAUD_RDMAE, UARTBAUD);
1421
1422		if (sport->dma_idle_int) {
1423			unsigned long ctrl = lpuart32_read(&sport->port, UARTCTRL);
1424
1425			lpuart32_write(&sport->port, ctrl | UARTCTRL_ILIE, UARTCTRL);
1426		}
1427	} else {
1428		writeb(readb(sport->port.membase + UARTCR5) | UARTCR5_RDMAS,
1429		       sport->port.membase + UARTCR5);
1430	}
1431
1432	return 0;
1433}
1434
1435static void lpuart_dma_rx_free(struct uart_port *port)
1436{
1437	struct lpuart_port *sport = container_of(port,
1438					struct lpuart_port, port);
1439	struct dma_chan *chan = sport->dma_rx_chan;
1440
1441	dmaengine_terminate_sync(chan);
1442	if (!sport->dma_idle_int)
1443		del_timer_sync(&sport->lpuart_timer);
1444
1445	dma_unmap_sg(chan->device->dev, &sport->rx_sgl, 1, DMA_FROM_DEVICE);
1446	kfree(sport->rx_ring.buf);
1447	sport->rx_ring.tail = 0;
1448	sport->rx_ring.head = 0;
1449	sport->dma_rx_desc = NULL;
1450	sport->dma_rx_cookie = -EINVAL;
1451}
1452
1453static int lpuart_config_rs485(struct uart_port *port, struct ktermios *termios,
1454			struct serial_rs485 *rs485)
1455{
1456	struct lpuart_port *sport = container_of(port,
1457			struct lpuart_port, port);
1458
1459	u8 modem = readb(sport->port.membase + UARTMODEM) &
1460		~(UARTMODEM_TXRTSPOL | UARTMODEM_TXRTSE);
1461	writeb(modem, sport->port.membase + UARTMODEM);
1462
1463	if (rs485->flags & SER_RS485_ENABLED) {
1464		/* Enable auto RS-485 RTS mode */
1465		modem |= UARTMODEM_TXRTSE;
1466
1467		/*
1468		 * The hardware defaults to RTS logic HIGH while transfer.
1469		 * Switch polarity in case RTS shall be logic HIGH
1470		 * after transfer.
1471		 * Note: UART is assumed to be active high.
1472		 */
1473		if (rs485->flags & SER_RS485_RTS_ON_SEND)
1474			modem |= UARTMODEM_TXRTSPOL;
1475		else if (rs485->flags & SER_RS485_RTS_AFTER_SEND)
1476			modem &= ~UARTMODEM_TXRTSPOL;
1477	}
1478
1479	writeb(modem, sport->port.membase + UARTMODEM);
1480	return 0;
1481}
1482
1483static int lpuart32_config_rs485(struct uart_port *port, struct ktermios *termios,
1484			struct serial_rs485 *rs485)
1485{
1486	struct lpuart_port *sport = container_of(port,
1487			struct lpuart_port, port);
1488
1489	unsigned long modem = lpuart32_read(&sport->port, UARTMODIR)
1490				& ~(UARTMODIR_TXRTSPOL | UARTMODIR_TXRTSE);
1491	lpuart32_write(&sport->port, modem, UARTMODIR);
1492
1493	if (rs485->flags & SER_RS485_ENABLED) {
1494		/* Enable auto RS-485 RTS mode */
1495		modem |= UARTMODIR_TXRTSE;
1496
1497		/*
1498		 * The hardware defaults to RTS logic HIGH while transfer.
1499		 * Switch polarity in case RTS shall be logic HIGH
1500		 * after transfer.
1501		 * Note: UART is assumed to be active high.
1502		 */
1503		if (rs485->flags & SER_RS485_RTS_ON_SEND)
1504			modem |= UARTMODIR_TXRTSPOL;
1505		else if (rs485->flags & SER_RS485_RTS_AFTER_SEND)
1506			modem &= ~UARTMODIR_TXRTSPOL;
1507	}
1508
1509	lpuart32_write(&sport->port, modem, UARTMODIR);
1510	return 0;
1511}
1512
1513static unsigned int lpuart_get_mctrl(struct uart_port *port)
1514{
1515	unsigned int mctrl = 0;
1516	u8 reg;
1517
1518	reg = readb(port->membase + UARTCR1);
1519	if (reg & UARTCR1_LOOPS)
1520		mctrl |= TIOCM_LOOP;
1521
1522	return mctrl;
1523}
1524
1525static unsigned int lpuart32_get_mctrl(struct uart_port *port)
1526{
1527	unsigned int mctrl = TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
1528	u32 reg;
1529
1530	reg = lpuart32_read(port, UARTCTRL);
1531	if (reg & UARTCTRL_LOOPS)
1532		mctrl |= TIOCM_LOOP;
1533
1534	return mctrl;
1535}
1536
1537static void lpuart_set_mctrl(struct uart_port *port, unsigned int mctrl)
1538{
1539	u8 reg;
1540
1541	reg = readb(port->membase + UARTCR1);
1542
1543	/* for internal loopback we need LOOPS=1 and RSRC=0 */
1544	reg &= ~(UARTCR1_LOOPS | UARTCR1_RSRC);
1545	if (mctrl & TIOCM_LOOP)
1546		reg |= UARTCR1_LOOPS;
1547
1548	writeb(reg, port->membase + UARTCR1);
1549}
1550
1551static void lpuart32_set_mctrl(struct uart_port *port, unsigned int mctrl)
1552{
1553	u32 reg;
1554
1555	reg = lpuart32_read(port, UARTCTRL);
1556
1557	/* for internal loopback we need LOOPS=1 and RSRC=0 */
1558	reg &= ~(UARTCTRL_LOOPS | UARTCTRL_RSRC);
1559	if (mctrl & TIOCM_LOOP)
1560		reg |= UARTCTRL_LOOPS;
1561
1562	lpuart32_write(port, reg, UARTCTRL);
1563}
1564
1565static void lpuart_break_ctl(struct uart_port *port, int break_state)
1566{
1567	unsigned char temp;
1568
1569	temp = readb(port->membase + UARTCR2) & ~UARTCR2_SBK;
1570
1571	if (break_state != 0)
1572		temp |= UARTCR2_SBK;
1573
1574	writeb(temp, port->membase + UARTCR2);
1575}
1576
1577static void lpuart32_break_ctl(struct uart_port *port, int break_state)
1578{
1579	unsigned long temp;
1580
1581	temp = lpuart32_read(port, UARTCTRL);
1582
1583	/*
1584	 * LPUART IP now has two known bugs, one is CTS has higher priority than the
1585	 * break signal, which causes the break signal sending through UARTCTRL_SBK
1586	 * may impacted by the CTS input if the HW flow control is enabled. It
1587	 * exists on all platforms we support in this driver.
1588	 * Another bug is i.MX8QM LPUART may have an additional break character
1589	 * being sent after SBK was cleared.
1590	 * To avoid above two bugs, we use Transmit Data Inversion function to send
1591	 * the break signal instead of UARTCTRL_SBK.
1592	 */
1593	if (break_state != 0) {
1594		/*
1595		 * Disable the transmitter to prevent any data from being sent out
1596		 * during break, then invert the TX line to send break.
1597		 */
1598		temp &= ~UARTCTRL_TE;
1599		lpuart32_write(port, temp, UARTCTRL);
1600		temp |= UARTCTRL_TXINV;
1601		lpuart32_write(port, temp, UARTCTRL);
1602	} else {
1603		/* Disable the TXINV to turn off break and re-enable transmitter. */
1604		temp &= ~UARTCTRL_TXINV;
1605		lpuart32_write(port, temp, UARTCTRL);
1606		temp |= UARTCTRL_TE;
1607		lpuart32_write(port, temp, UARTCTRL);
1608	}
1609}
1610
1611static void lpuart_setup_watermark(struct lpuart_port *sport)
1612{
1613	unsigned char val, cr2;
1614	unsigned char cr2_saved;
1615
1616	cr2 = readb(sport->port.membase + UARTCR2);
1617	cr2_saved = cr2;
1618	cr2 &= ~(UARTCR2_TIE | UARTCR2_TCIE | UARTCR2_TE |
1619			UARTCR2_RIE | UARTCR2_RE);
1620	writeb(cr2, sport->port.membase + UARTCR2);
1621
1622	val = readb(sport->port.membase + UARTPFIFO);
1623	writeb(val | UARTPFIFO_TXFE | UARTPFIFO_RXFE,
1624			sport->port.membase + UARTPFIFO);
1625
1626	/* flush Tx and Rx FIFO */
1627	writeb(UARTCFIFO_TXFLUSH | UARTCFIFO_RXFLUSH,
1628			sport->port.membase + UARTCFIFO);
1629
1630	/* explicitly clear RDRF */
1631	if (readb(sport->port.membase + UARTSR1) & UARTSR1_RDRF) {
1632		readb(sport->port.membase + UARTDR);
1633		writeb(UARTSFIFO_RXUF, sport->port.membase + UARTSFIFO);
1634	}
1635
1636	if (uart_console(&sport->port))
1637		sport->rx_watermark = 1;
1638	writeb(0, sport->port.membase + UARTTWFIFO);
1639	writeb(sport->rx_watermark, sport->port.membase + UARTRWFIFO);
1640
1641	/* Restore cr2 */
1642	writeb(cr2_saved, sport->port.membase + UARTCR2);
1643}
1644
1645static void lpuart_setup_watermark_enable(struct lpuart_port *sport)
1646{
1647	unsigned char cr2;
1648
1649	lpuart_setup_watermark(sport);
1650
1651	cr2 = readb(sport->port.membase + UARTCR2);
1652	cr2 |= UARTCR2_RIE | UARTCR2_RE | UARTCR2_TE;
1653	writeb(cr2, sport->port.membase + UARTCR2);
1654}
1655
1656static void lpuart32_setup_watermark(struct lpuart_port *sport)
1657{
1658	unsigned long val, ctrl;
1659	unsigned long ctrl_saved;
1660
1661	ctrl = lpuart32_read(&sport->port, UARTCTRL);
1662	ctrl_saved = ctrl;
1663	ctrl &= ~(UARTCTRL_TIE | UARTCTRL_TCIE | UARTCTRL_TE |
1664			UARTCTRL_RIE | UARTCTRL_RE | UARTCTRL_ILIE);
1665	lpuart32_write(&sport->port, ctrl, UARTCTRL);
1666
1667	/* enable FIFO mode */
1668	val = lpuart32_read(&sport->port, UARTFIFO);
1669	val |= UARTFIFO_TXFE | UARTFIFO_RXFE;
1670	val |= UARTFIFO_TXFLUSH | UARTFIFO_RXFLUSH;
1671	val |= FIELD_PREP(UARTFIFO_RXIDEN, 0x3);
1672	lpuart32_write(&sport->port, val, UARTFIFO);
1673
1674	/* set the watermark */
1675	if (uart_console(&sport->port))
1676		sport->rx_watermark = 1;
1677	val = (sport->rx_watermark << UARTWATER_RXWATER_OFF) |
1678	      (0x0 << UARTWATER_TXWATER_OFF);
1679	lpuart32_write(&sport->port, val, UARTWATER);
1680
1681	/* set RTS watermark */
1682	if (!uart_console(&sport->port)) {
1683		val = lpuart32_read(&sport->port, UARTMODIR);
1684		val |= FIELD_PREP(UARTMODIR_RTSWATER, sport->rxfifo_size >> 1);
1685		lpuart32_write(&sport->port, val, UARTMODIR);
1686	}
1687
1688	/* Restore cr2 */
1689	lpuart32_write(&sport->port, ctrl_saved, UARTCTRL);
1690}
1691
1692static void lpuart32_setup_watermark_enable(struct lpuart_port *sport)
1693{
1694	u32 temp;
1695
1696	lpuart32_setup_watermark(sport);
1697
1698	temp = lpuart32_read(&sport->port, UARTCTRL);
1699	temp |= UARTCTRL_RE | UARTCTRL_TE;
1700	temp |= FIELD_PREP(UARTCTRL_IDLECFG, 0x7);
1701	lpuart32_write(&sport->port, temp, UARTCTRL);
1702}
1703
1704static void rx_dma_timer_init(struct lpuart_port *sport)
1705{
1706	if (sport->dma_idle_int)
1707		return;
1708
1709	timer_setup(&sport->lpuart_timer, lpuart_timer_func, 0);
1710	sport->lpuart_timer.expires = jiffies + sport->dma_rx_timeout;
1711	add_timer(&sport->lpuart_timer);
1712}
1713
1714static void lpuart_request_dma(struct lpuart_port *sport)
1715{
1716	sport->dma_tx_chan = dma_request_chan(sport->port.dev, "tx");
1717	if (IS_ERR(sport->dma_tx_chan)) {
1718		dev_dbg_once(sport->port.dev,
1719			     "DMA tx channel request failed, operating without tx DMA (%ld)\n",
1720			     PTR_ERR(sport->dma_tx_chan));
1721		sport->dma_tx_chan = NULL;
1722	}
1723
1724	sport->dma_rx_chan = dma_request_chan(sport->port.dev, "rx");
1725	if (IS_ERR(sport->dma_rx_chan)) {
1726		dev_dbg_once(sport->port.dev,
1727			     "DMA rx channel request failed, operating without rx DMA (%ld)\n",
1728			     PTR_ERR(sport->dma_rx_chan));
1729		sport->dma_rx_chan = NULL;
1730	}
1731}
1732
1733static void lpuart_tx_dma_startup(struct lpuart_port *sport)
1734{
1735	u32 uartbaud;
1736	int ret;
1737
1738	if (uart_console(&sport->port))
1739		goto err;
1740
1741	if (!sport->dma_tx_chan)
1742		goto err;
1743
1744	ret = lpuart_dma_tx_request(&sport->port);
1745	if (ret)
1746		goto err;
1747
1748	init_waitqueue_head(&sport->dma_wait);
1749	sport->lpuart_dma_tx_use = true;
1750	if (lpuart_is_32(sport)) {
1751		uartbaud = lpuart32_read(&sport->port, UARTBAUD);
1752		lpuart32_write(&sport->port,
1753			       uartbaud | UARTBAUD_TDMAE, UARTBAUD);
1754	} else {
1755		writeb(readb(sport->port.membase + UARTCR5) |
1756		       UARTCR5_TDMAS, sport->port.membase + UARTCR5);
1757	}
1758
1759	return;
1760
1761err:
1762	sport->lpuart_dma_tx_use = false;
1763}
1764
1765static void lpuart_rx_dma_startup(struct lpuart_port *sport)
1766{
1767	int ret;
1768	unsigned char cr3;
1769
1770	if (uart_console(&sport->port))
1771		goto err;
1772
1773	if (!sport->dma_rx_chan)
1774		goto err;
1775
1776	/* set default Rx DMA timeout */
1777	sport->dma_rx_timeout = msecs_to_jiffies(DMA_RX_TIMEOUT);
1778
1779	ret = lpuart_start_rx_dma(sport);
1780	if (ret)
1781		goto err;
1782
 
 
1783	if (!sport->dma_rx_timeout)
1784		sport->dma_rx_timeout = 1;
1785
1786	sport->lpuart_dma_rx_use = true;
1787	rx_dma_timer_init(sport);
1788
1789	if (sport->port.has_sysrq && !lpuart_is_32(sport)) {
1790		cr3 = readb(sport->port.membase + UARTCR3);
1791		cr3 |= UARTCR3_FEIE;
1792		writeb(cr3, sport->port.membase + UARTCR3);
1793	}
1794
1795	return;
1796
1797err:
1798	sport->lpuart_dma_rx_use = false;
1799}
1800
1801static void lpuart_hw_setup(struct lpuart_port *sport)
1802{
1803	unsigned long flags;
1804
1805	uart_port_lock_irqsave(&sport->port, &flags);
1806
1807	lpuart_setup_watermark_enable(sport);
1808
1809	lpuart_rx_dma_startup(sport);
1810	lpuart_tx_dma_startup(sport);
1811
1812	uart_port_unlock_irqrestore(&sport->port, flags);
1813}
1814
1815static int lpuart_startup(struct uart_port *port)
1816{
1817	struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
1818	unsigned char temp;
1819
1820	/* determine FIFO size and enable FIFO mode */
1821	temp = readb(sport->port.membase + UARTPFIFO);
1822
1823	sport->txfifo_size = UARTFIFO_DEPTH((temp >> UARTPFIFO_TXSIZE_OFF) &
1824					    UARTPFIFO_FIFOSIZE_MASK);
1825	sport->port.fifosize = sport->txfifo_size;
1826
1827	sport->rxfifo_size = UARTFIFO_DEPTH((temp >> UARTPFIFO_RXSIZE_OFF) &
1828					    UARTPFIFO_FIFOSIZE_MASK);
1829
1830	lpuart_request_dma(sport);
1831	lpuart_hw_setup(sport);
1832
1833	return 0;
1834}
1835
1836static void lpuart32_hw_disable(struct lpuart_port *sport)
1837{
1838	unsigned long temp;
1839
1840	temp = lpuart32_read(&sport->port, UARTCTRL);
1841	temp &= ~(UARTCTRL_RIE | UARTCTRL_ILIE | UARTCTRL_RE |
1842		  UARTCTRL_TIE | UARTCTRL_TE);
1843	lpuart32_write(&sport->port, temp, UARTCTRL);
1844}
1845
1846static void lpuart32_configure(struct lpuart_port *sport)
1847{
1848	unsigned long temp;
1849
 
 
 
 
 
 
1850	temp = lpuart32_read(&sport->port, UARTCTRL);
1851	if (!sport->lpuart_dma_rx_use)
1852		temp |= UARTCTRL_RIE | UARTCTRL_ILIE;
1853	if (!sport->lpuart_dma_tx_use)
1854		temp |= UARTCTRL_TIE;
1855	lpuart32_write(&sport->port, temp, UARTCTRL);
1856}
1857
1858static void lpuart32_hw_setup(struct lpuart_port *sport)
1859{
1860	unsigned long flags;
1861
1862	uart_port_lock_irqsave(&sport->port, &flags);
1863
1864	lpuart32_hw_disable(sport);
1865
1866	lpuart_rx_dma_startup(sport);
1867	lpuart_tx_dma_startup(sport);
1868
1869	lpuart32_setup_watermark_enable(sport);
1870	lpuart32_configure(sport);
1871
1872	uart_port_unlock_irqrestore(&sport->port, flags);
1873}
1874
1875static int lpuart32_startup(struct uart_port *port)
1876{
1877	struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
1878	unsigned long temp;
1879
1880	/* determine FIFO size */
1881	temp = lpuart32_read(&sport->port, UARTFIFO);
1882
1883	sport->txfifo_size = UARTFIFO_DEPTH((temp >> UARTFIFO_TXSIZE_OFF) &
1884					    UARTFIFO_FIFOSIZE_MASK);
1885	sport->port.fifosize = sport->txfifo_size;
1886
1887	sport->rxfifo_size = UARTFIFO_DEPTH((temp >> UARTFIFO_RXSIZE_OFF) &
1888					    UARTFIFO_FIFOSIZE_MASK);
1889
1890	/*
1891	 * The LS1021A and LS1028A have a fixed FIFO depth of 16 words.
1892	 * Although they support the RX/TXSIZE fields, their encoding is
1893	 * different. Eg the reference manual states 0b101 is 16 words.
1894	 */
1895	if (is_layerscape_lpuart(sport)) {
1896		sport->rxfifo_size = 16;
1897		sport->txfifo_size = 16;
1898		sport->port.fifosize = sport->txfifo_size;
1899	}
1900
1901	lpuart_request_dma(sport);
1902	lpuart32_hw_setup(sport);
1903
1904	return 0;
1905}
1906
1907static void lpuart_dma_shutdown(struct lpuart_port *sport)
1908{
1909	if (sport->lpuart_dma_rx_use) {
 
1910		lpuart_dma_rx_free(&sport->port);
1911		sport->lpuart_dma_rx_use = false;
1912	}
1913
1914	if (sport->lpuart_dma_tx_use) {
1915		if (wait_event_interruptible_timeout(sport->dma_wait,
1916			!sport->dma_tx_in_progress, msecs_to_jiffies(300)) <= 0) {
1917			sport->dma_tx_in_progress = false;
1918			dmaengine_terminate_sync(sport->dma_tx_chan);
1919		}
1920		sport->lpuart_dma_tx_use = false;
1921	}
1922
1923	if (sport->dma_tx_chan)
1924		dma_release_channel(sport->dma_tx_chan);
1925	if (sport->dma_rx_chan)
1926		dma_release_channel(sport->dma_rx_chan);
1927}
1928
1929static void lpuart_shutdown(struct uart_port *port)
1930{
1931	struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
1932	unsigned char temp;
1933	unsigned long flags;
1934
1935	uart_port_lock_irqsave(port, &flags);
1936
1937	/* disable Rx/Tx and interrupts */
1938	temp = readb(port->membase + UARTCR2);
1939	temp &= ~(UARTCR2_TE | UARTCR2_RE |
1940			UARTCR2_TIE | UARTCR2_TCIE | UARTCR2_RIE);
1941	writeb(temp, port->membase + UARTCR2);
1942
1943	uart_port_unlock_irqrestore(port, flags);
1944
1945	lpuart_dma_shutdown(sport);
1946}
1947
1948static void lpuart32_shutdown(struct uart_port *port)
1949{
1950	struct lpuart_port *sport =
1951		container_of(port, struct lpuart_port, port);
1952	unsigned long temp;
1953	unsigned long flags;
1954
1955	uart_port_lock_irqsave(port, &flags);
1956
1957	/* clear status */
1958	temp = lpuart32_read(&sport->port, UARTSTAT);
1959	lpuart32_write(&sport->port, temp, UARTSTAT);
1960
1961	/* disable Rx/Tx DMA */
1962	temp = lpuart32_read(port, UARTBAUD);
1963	temp &= ~(UARTBAUD_TDMAE | UARTBAUD_RDMAE);
1964	lpuart32_write(port, temp, UARTBAUD);
1965
1966	/* disable Rx/Tx and interrupts and break condition */
1967	temp = lpuart32_read(port, UARTCTRL);
1968	temp &= ~(UARTCTRL_TE | UARTCTRL_RE | UARTCTRL_ILIE |
1969			UARTCTRL_TIE | UARTCTRL_TCIE | UARTCTRL_RIE | UARTCTRL_SBK);
1970	lpuart32_write(port, temp, UARTCTRL);
1971
1972	uart_port_unlock_irqrestore(port, flags);
1973
1974	lpuart_dma_shutdown(sport);
1975}
1976
1977static void
1978lpuart_set_termios(struct uart_port *port, struct ktermios *termios,
1979		   const struct ktermios *old)
1980{
1981	struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
1982	unsigned long flags;
1983	unsigned char cr1, old_cr1, old_cr2, cr3, cr4, bdh, modem;
1984	unsigned int  baud;
1985	unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8;
1986	unsigned int sbr, brfa;
1987
1988	cr1 = old_cr1 = readb(sport->port.membase + UARTCR1);
1989	old_cr2 = readb(sport->port.membase + UARTCR2);
1990	cr3 = readb(sport->port.membase + UARTCR3);
1991	cr4 = readb(sport->port.membase + UARTCR4);
1992	bdh = readb(sport->port.membase + UARTBDH);
1993	modem = readb(sport->port.membase + UARTMODEM);
1994	/*
1995	 * only support CS8 and CS7, and for CS7 must enable PE.
1996	 * supported mode:
1997	 *  - (7,e/o,1)
1998	 *  - (8,n,1)
1999	 *  - (8,m/s,1)
2000	 *  - (8,e/o,1)
2001	 */
2002	while ((termios->c_cflag & CSIZE) != CS8 &&
2003		(termios->c_cflag & CSIZE) != CS7) {
2004		termios->c_cflag &= ~CSIZE;
2005		termios->c_cflag |= old_csize;
2006		old_csize = CS8;
2007	}
2008
2009	if ((termios->c_cflag & CSIZE) == CS8 ||
2010		(termios->c_cflag & CSIZE) == CS7)
2011		cr1 = old_cr1 & ~UARTCR1_M;
2012
2013	if (termios->c_cflag & CMSPAR) {
2014		if ((termios->c_cflag & CSIZE) != CS8) {
2015			termios->c_cflag &= ~CSIZE;
2016			termios->c_cflag |= CS8;
2017		}
2018		cr1 |= UARTCR1_M;
2019	}
2020
2021	/*
2022	 * When auto RS-485 RTS mode is enabled,
2023	 * hardware flow control need to be disabled.
2024	 */
2025	if (sport->port.rs485.flags & SER_RS485_ENABLED)
2026		termios->c_cflag &= ~CRTSCTS;
2027
2028	if (termios->c_cflag & CRTSCTS)
2029		modem |= UARTMODEM_RXRTSE | UARTMODEM_TXCTSE;
2030	else
2031		modem &= ~(UARTMODEM_RXRTSE | UARTMODEM_TXCTSE);
2032
2033	termios->c_cflag &= ~CSTOPB;
2034
2035	/* parity must be enabled when CS7 to match 8-bits format */
2036	if ((termios->c_cflag & CSIZE) == CS7)
2037		termios->c_cflag |= PARENB;
2038
2039	if (termios->c_cflag & PARENB) {
2040		if (termios->c_cflag & CMSPAR) {
2041			cr1 &= ~UARTCR1_PE;
2042			if (termios->c_cflag & PARODD)
2043				cr3 |= UARTCR3_T8;
2044			else
2045				cr3 &= ~UARTCR3_T8;
2046		} else {
2047			cr1 |= UARTCR1_PE;
2048			if ((termios->c_cflag & CSIZE) == CS8)
2049				cr1 |= UARTCR1_M;
2050			if (termios->c_cflag & PARODD)
2051				cr1 |= UARTCR1_PT;
2052			else
2053				cr1 &= ~UARTCR1_PT;
2054		}
2055	} else {
2056		cr1 &= ~UARTCR1_PE;
2057	}
2058
2059	/* ask the core to calculate the divisor */
2060	baud = uart_get_baud_rate(port, termios, old, 50, port->uartclk / 16);
2061
2062	/*
2063	 * Need to update the Ring buffer length according to the selected
2064	 * baud rate and restart Rx DMA path.
2065	 *
2066	 * Since timer function acqures sport->port.lock, need to stop before
2067	 * acquring same lock because otherwise del_timer_sync() can deadlock.
2068	 */
2069	if (old && sport->lpuart_dma_rx_use)
 
2070		lpuart_dma_rx_free(&sport->port);
 
2071
2072	uart_port_lock_irqsave(&sport->port, &flags);
2073
2074	sport->port.read_status_mask = 0;
2075	if (termios->c_iflag & INPCK)
2076		sport->port.read_status_mask |= UARTSR1_FE | UARTSR1_PE;
2077	if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
2078		sport->port.read_status_mask |= UARTSR1_FE;
2079
2080	/* characters to ignore */
2081	sport->port.ignore_status_mask = 0;
2082	if (termios->c_iflag & IGNPAR)
2083		sport->port.ignore_status_mask |= UARTSR1_PE;
2084	if (termios->c_iflag & IGNBRK) {
2085		sport->port.ignore_status_mask |= UARTSR1_FE;
2086		/*
2087		 * if we're ignoring parity and break indicators,
2088		 * ignore overruns too (for real raw support).
2089		 */
2090		if (termios->c_iflag & IGNPAR)
2091			sport->port.ignore_status_mask |= UARTSR1_OR;
2092	}
2093
2094	/* update the per-port timeout */
2095	uart_update_timeout(port, termios->c_cflag, baud);
2096
2097	/* wait transmit engin complete */
2098	lpuart_wait_bit_set(&sport->port, UARTSR1, UARTSR1_TC);
2099
2100	/* disable transmit and receive */
2101	writeb(old_cr2 & ~(UARTCR2_TE | UARTCR2_RE),
2102			sport->port.membase + UARTCR2);
2103
2104	sbr = sport->port.uartclk / (16 * baud);
2105	brfa = ((sport->port.uartclk - (16 * sbr * baud)) * 2) / baud;
2106	bdh &= ~UARTBDH_SBR_MASK;
2107	bdh |= (sbr >> 8) & 0x1F;
2108	cr4 &= ~UARTCR4_BRFA_MASK;
2109	brfa &= UARTCR4_BRFA_MASK;
2110	writeb(cr4 | brfa, sport->port.membase + UARTCR4);
2111	writeb(bdh, sport->port.membase + UARTBDH);
2112	writeb(sbr & 0xFF, sport->port.membase + UARTBDL);
2113	writeb(cr3, sport->port.membase + UARTCR3);
2114	writeb(cr1, sport->port.membase + UARTCR1);
2115	writeb(modem, sport->port.membase + UARTMODEM);
2116
2117	/* restore control register */
2118	writeb(old_cr2, sport->port.membase + UARTCR2);
2119
2120	if (old && sport->lpuart_dma_rx_use) {
2121		if (!lpuart_start_rx_dma(sport))
2122			rx_dma_timer_init(sport);
2123		else
2124			sport->lpuart_dma_rx_use = false;
2125	}
2126
2127	uart_port_unlock_irqrestore(&sport->port, flags);
2128}
2129
2130static void __lpuart32_serial_setbrg(struct uart_port *port,
2131				     unsigned int baudrate, bool use_rx_dma,
2132				     bool use_tx_dma)
2133{
2134	u32 sbr, osr, baud_diff, tmp_osr, tmp_sbr, tmp_diff, tmp;
2135	u32 clk = port->uartclk;
2136
2137	/*
2138	 * The idea is to use the best OSR (over-sampling rate) possible.
2139	 * Note, OSR is typically hard-set to 16 in other LPUART instantiations.
2140	 * Loop to find the best OSR value possible, one that generates minimum
2141	 * baud_diff iterate through the rest of the supported values of OSR.
2142	 *
2143	 * Calculation Formula:
2144	 *  Baud Rate = baud clock / ((OSR+1) × SBR)
2145	 */
2146	baud_diff = baudrate;
2147	osr = 0;
2148	sbr = 0;
2149
2150	for (tmp_osr = 4; tmp_osr <= 32; tmp_osr++) {
2151		/* calculate the temporary sbr value  */
2152		tmp_sbr = (clk / (baudrate * tmp_osr));
2153		if (tmp_sbr == 0)
2154			tmp_sbr = 1;
2155
2156		/*
2157		 * calculate the baud rate difference based on the temporary
2158		 * osr and sbr values
2159		 */
2160		tmp_diff = clk / (tmp_osr * tmp_sbr) - baudrate;
2161
2162		/* select best values between sbr and sbr+1 */
2163		tmp = clk / (tmp_osr * (tmp_sbr + 1));
2164		if (tmp_diff > (baudrate - tmp)) {
2165			tmp_diff = baudrate - tmp;
2166			tmp_sbr++;
2167		}
2168
2169		if (tmp_sbr > UARTBAUD_SBR_MASK)
2170			continue;
2171
2172		if (tmp_diff <= baud_diff) {
2173			baud_diff = tmp_diff;
2174			osr = tmp_osr;
2175			sbr = tmp_sbr;
2176
2177			if (!baud_diff)
2178				break;
2179		}
2180	}
2181
2182	/* handle buadrate outside acceptable rate */
2183	if (baud_diff > ((baudrate / 100) * 3))
2184		dev_warn(port->dev,
2185			 "unacceptable baud rate difference of more than 3%%\n");
2186
2187	tmp = lpuart32_read(port, UARTBAUD);
2188
2189	if ((osr > 3) && (osr < 8))
2190		tmp |= UARTBAUD_BOTHEDGE;
2191
2192	tmp &= ~(UARTBAUD_OSR_MASK << UARTBAUD_OSR_SHIFT);
2193	tmp |= ((osr-1) & UARTBAUD_OSR_MASK) << UARTBAUD_OSR_SHIFT;
2194
2195	tmp &= ~UARTBAUD_SBR_MASK;
2196	tmp |= sbr & UARTBAUD_SBR_MASK;
2197
2198	if (!use_rx_dma)
2199		tmp &= ~UARTBAUD_RDMAE;
2200	if (!use_tx_dma)
2201		tmp &= ~UARTBAUD_TDMAE;
2202
2203	lpuart32_write(port, tmp, UARTBAUD);
2204}
2205
2206static void lpuart32_serial_setbrg(struct lpuart_port *sport,
2207				   unsigned int baudrate)
2208{
2209	__lpuart32_serial_setbrg(&sport->port, baudrate,
2210				 sport->lpuart_dma_rx_use,
2211				 sport->lpuart_dma_tx_use);
2212}
2213
2214
2215static void
2216lpuart32_set_termios(struct uart_port *port, struct ktermios *termios,
2217		     const struct ktermios *old)
2218{
2219	struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
2220	unsigned long flags;
2221	unsigned long ctrl, old_ctrl, bd, modem;
2222	unsigned int  baud;
2223	unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8;
2224
2225	ctrl = old_ctrl = lpuart32_read(&sport->port, UARTCTRL);
2226	bd = lpuart32_read(&sport->port, UARTBAUD);
2227	modem = lpuart32_read(&sport->port, UARTMODIR);
2228	sport->is_cs7 = false;
2229	/*
2230	 * only support CS8 and CS7, and for CS7 must enable PE.
2231	 * supported mode:
2232	 *  - (7,e/o,1)
2233	 *  - (8,n,1)
2234	 *  - (8,m/s,1)
2235	 *  - (8,e/o,1)
2236	 */
2237	while ((termios->c_cflag & CSIZE) != CS8 &&
2238		(termios->c_cflag & CSIZE) != CS7) {
2239		termios->c_cflag &= ~CSIZE;
2240		termios->c_cflag |= old_csize;
2241		old_csize = CS8;
2242	}
2243
2244	if ((termios->c_cflag & CSIZE) == CS8 ||
2245		(termios->c_cflag & CSIZE) == CS7)
2246		ctrl = old_ctrl & ~UARTCTRL_M;
2247
2248	if (termios->c_cflag & CMSPAR) {
2249		if ((termios->c_cflag & CSIZE) != CS8) {
2250			termios->c_cflag &= ~CSIZE;
2251			termios->c_cflag |= CS8;
2252		}
2253		ctrl |= UARTCTRL_M;
2254	}
2255
2256	/*
2257	 * When auto RS-485 RTS mode is enabled,
2258	 * hardware flow control need to be disabled.
2259	 */
2260	if (sport->port.rs485.flags & SER_RS485_ENABLED)
2261		termios->c_cflag &= ~CRTSCTS;
2262
2263	if (termios->c_cflag & CRTSCTS)
2264		modem |= UARTMODIR_RXRTSE | UARTMODIR_TXCTSE;
2265	else
2266		modem &= ~(UARTMODIR_RXRTSE | UARTMODIR_TXCTSE);
2267
2268	if (termios->c_cflag & CSTOPB)
2269		bd |= UARTBAUD_SBNS;
2270	else
2271		bd &= ~UARTBAUD_SBNS;
2272
2273	/* parity must be enabled when CS7 to match 8-bits format */
2274	if ((termios->c_cflag & CSIZE) == CS7)
2275		termios->c_cflag |= PARENB;
2276
2277	if ((termios->c_cflag & PARENB)) {
2278		if (termios->c_cflag & CMSPAR) {
2279			ctrl &= ~UARTCTRL_PE;
2280			ctrl |= UARTCTRL_M;
2281		} else {
2282			ctrl |= UARTCTRL_PE;
2283			if ((termios->c_cflag & CSIZE) == CS8)
2284				ctrl |= UARTCTRL_M;
2285			if (termios->c_cflag & PARODD)
2286				ctrl |= UARTCTRL_PT;
2287			else
2288				ctrl &= ~UARTCTRL_PT;
2289		}
2290	} else {
2291		ctrl &= ~UARTCTRL_PE;
2292	}
2293
2294	/* ask the core to calculate the divisor */
2295	baud = uart_get_baud_rate(port, termios, old, 50, port->uartclk / 4);
2296
2297	/*
2298	 * Need to update the Ring buffer length according to the selected
2299	 * baud rate and restart Rx DMA path.
2300	 *
2301	 * Since timer function acqures sport->port.lock, need to stop before
2302	 * acquring same lock because otherwise del_timer_sync() can deadlock.
2303	 */
2304	if (old && sport->lpuart_dma_rx_use)
 
2305		lpuart_dma_rx_free(&sport->port);
 
2306
2307	uart_port_lock_irqsave(&sport->port, &flags);
2308
2309	sport->port.read_status_mask = 0;
2310	if (termios->c_iflag & INPCK)
2311		sport->port.read_status_mask |= UARTSTAT_FE | UARTSTAT_PE;
2312	if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
2313		sport->port.read_status_mask |= UARTSTAT_FE;
2314
2315	/* characters to ignore */
2316	sport->port.ignore_status_mask = 0;
2317	if (termios->c_iflag & IGNPAR)
2318		sport->port.ignore_status_mask |= UARTSTAT_PE;
2319	if (termios->c_iflag & IGNBRK) {
2320		sport->port.ignore_status_mask |= UARTSTAT_FE;
2321		/*
2322		 * if we're ignoring parity and break indicators,
2323		 * ignore overruns too (for real raw support).
2324		 */
2325		if (termios->c_iflag & IGNPAR)
2326			sport->port.ignore_status_mask |= UARTSTAT_OR;
2327	}
2328
2329	/* update the per-port timeout */
2330	uart_update_timeout(port, termios->c_cflag, baud);
2331
2332	/*
2333	 * LPUART Transmission Complete Flag may never be set while queuing a break
2334	 * character, so skip waiting for transmission complete when UARTCTRL_SBK is
2335	 * asserted.
2336	 */
2337	if (!(old_ctrl & UARTCTRL_SBK)) {
2338		lpuart32_write(&sport->port, 0, UARTMODIR);
2339		lpuart32_wait_bit_set(&sport->port, UARTSTAT, UARTSTAT_TC);
2340	}
2341
2342	/* disable transmit and receive */
2343	lpuart32_write(&sport->port, old_ctrl & ~(UARTCTRL_TE | UARTCTRL_RE),
2344		       UARTCTRL);
2345
2346	lpuart32_write(&sport->port, bd, UARTBAUD);
2347	lpuart32_serial_setbrg(sport, baud);
2348	/* disable CTS before enabling UARTCTRL_TE to avoid pending idle preamble */
2349	lpuart32_write(&sport->port, modem & ~UARTMODIR_TXCTSE, UARTMODIR);
2350	/* restore control register */
2351	lpuart32_write(&sport->port, ctrl, UARTCTRL);
2352	/* re-enable the CTS if needed */
2353	lpuart32_write(&sport->port, modem, UARTMODIR);
 
 
2354
2355	if ((ctrl & (UARTCTRL_PE | UARTCTRL_M)) == UARTCTRL_PE)
2356		sport->is_cs7 = true;
2357
2358	if (old && sport->lpuart_dma_rx_use) {
2359		if (!lpuart_start_rx_dma(sport))
2360			rx_dma_timer_init(sport);
2361		else
2362			sport->lpuart_dma_rx_use = false;
2363	}
2364
2365	uart_port_unlock_irqrestore(&sport->port, flags);
2366}
2367
2368static const char *lpuart_type(struct uart_port *port)
2369{
2370	return "FSL_LPUART";
2371}
2372
2373static void lpuart_release_port(struct uart_port *port)
2374{
2375	/* nothing to do */
2376}
2377
2378static int lpuart_request_port(struct uart_port *port)
2379{
2380	return  0;
2381}
2382
2383/* configure/autoconfigure the port */
2384static void lpuart_config_port(struct uart_port *port, int flags)
2385{
2386	if (flags & UART_CONFIG_TYPE)
2387		port->type = PORT_LPUART;
2388}
2389
2390static int lpuart_verify_port(struct uart_port *port, struct serial_struct *ser)
2391{
2392	int ret = 0;
2393
2394	if (ser->type != PORT_UNKNOWN && ser->type != PORT_LPUART)
2395		ret = -EINVAL;
2396	if (port->irq != ser->irq)
2397		ret = -EINVAL;
2398	if (ser->io_type != UPIO_MEM)
2399		ret = -EINVAL;
2400	if (port->uartclk / 16 != ser->baud_base)
2401		ret = -EINVAL;
2402	if (port->iobase != ser->port)
2403		ret = -EINVAL;
2404	if (ser->hub6 != 0)
2405		ret = -EINVAL;
2406	return ret;
2407}
2408
2409static const struct uart_ops lpuart_pops = {
2410	.tx_empty	= lpuart_tx_empty,
2411	.set_mctrl	= lpuart_set_mctrl,
2412	.get_mctrl	= lpuart_get_mctrl,
2413	.stop_tx	= lpuart_stop_tx,
2414	.start_tx	= lpuart_start_tx,
2415	.stop_rx	= lpuart_stop_rx,
2416	.break_ctl	= lpuart_break_ctl,
2417	.startup	= lpuart_startup,
2418	.shutdown	= lpuart_shutdown,
2419	.set_termios	= lpuart_set_termios,
2420	.pm		= lpuart_uart_pm,
2421	.type		= lpuart_type,
2422	.request_port	= lpuart_request_port,
2423	.release_port	= lpuart_release_port,
2424	.config_port	= lpuart_config_port,
2425	.verify_port	= lpuart_verify_port,
2426	.flush_buffer	= lpuart_flush_buffer,
2427#if defined(CONFIG_CONSOLE_POLL)
2428	.poll_init	= lpuart_poll_init,
2429	.poll_get_char	= lpuart_poll_get_char,
2430	.poll_put_char	= lpuart_poll_put_char,
2431#endif
2432};
2433
2434static const struct uart_ops lpuart32_pops = {
2435	.tx_empty	= lpuart32_tx_empty,
2436	.set_mctrl	= lpuart32_set_mctrl,
2437	.get_mctrl	= lpuart32_get_mctrl,
2438	.stop_tx	= lpuart32_stop_tx,
2439	.start_tx	= lpuart32_start_tx,
2440	.stop_rx	= lpuart32_stop_rx,
2441	.break_ctl	= lpuart32_break_ctl,
2442	.startup	= lpuart32_startup,
2443	.shutdown	= lpuart32_shutdown,
2444	.set_termios	= lpuart32_set_termios,
2445	.pm		= lpuart_uart_pm,
2446	.type		= lpuart_type,
2447	.request_port	= lpuart_request_port,
2448	.release_port	= lpuart_release_port,
2449	.config_port	= lpuart_config_port,
2450	.verify_port	= lpuart_verify_port,
2451	.flush_buffer	= lpuart_flush_buffer,
2452#if defined(CONFIG_CONSOLE_POLL)
2453	.poll_init	= lpuart32_poll_init,
2454	.poll_get_char	= lpuart32_poll_get_char,
2455	.poll_put_char	= lpuart32_poll_put_char,
2456#endif
2457};
2458
2459static struct lpuart_port *lpuart_ports[UART_NR];
2460
2461#ifdef CONFIG_SERIAL_FSL_LPUART_CONSOLE
2462static void lpuart_console_putchar(struct uart_port *port, unsigned char ch)
2463{
2464	lpuart_wait_bit_set(port, UARTSR1, UARTSR1_TDRE);
2465	writeb(ch, port->membase + UARTDR);
2466}
2467
2468static void lpuart32_console_putchar(struct uart_port *port, unsigned char ch)
2469{
2470	lpuart32_wait_bit_set(port, UARTSTAT, UARTSTAT_TDRE);
2471	lpuart32_write(port, ch, UARTDATA);
2472}
2473
2474static void
2475lpuart_console_write(struct console *co, const char *s, unsigned int count)
2476{
2477	struct lpuart_port *sport = lpuart_ports[co->index];
2478	unsigned char  old_cr2, cr2;
2479	unsigned long flags;
2480	int locked = 1;
2481
2482	if (oops_in_progress)
2483		locked = uart_port_trylock_irqsave(&sport->port, &flags);
2484	else
2485		uart_port_lock_irqsave(&sport->port, &flags);
2486
2487	/* first save CR2 and then disable interrupts */
2488	cr2 = old_cr2 = readb(sport->port.membase + UARTCR2);
2489	cr2 |= UARTCR2_TE | UARTCR2_RE;
2490	cr2 &= ~(UARTCR2_TIE | UARTCR2_TCIE | UARTCR2_RIE);
2491	writeb(cr2, sport->port.membase + UARTCR2);
2492
2493	uart_console_write(&sport->port, s, count, lpuart_console_putchar);
2494
2495	/* wait for transmitter finish complete and restore CR2 */
2496	lpuart_wait_bit_set(&sport->port, UARTSR1, UARTSR1_TC);
2497
2498	writeb(old_cr2, sport->port.membase + UARTCR2);
2499
2500	if (locked)
2501		uart_port_unlock_irqrestore(&sport->port, flags);
2502}
2503
2504static void
2505lpuart32_console_write(struct console *co, const char *s, unsigned int count)
2506{
2507	struct lpuart_port *sport = lpuart_ports[co->index];
2508	unsigned long  old_cr, cr;
2509	unsigned long flags;
2510	int locked = 1;
2511
2512	if (oops_in_progress)
2513		locked = uart_port_trylock_irqsave(&sport->port, &flags);
2514	else
2515		uart_port_lock_irqsave(&sport->port, &flags);
2516
2517	/* first save CR2 and then disable interrupts */
2518	cr = old_cr = lpuart32_read(&sport->port, UARTCTRL);
2519	cr |= UARTCTRL_TE | UARTCTRL_RE;
2520	cr &= ~(UARTCTRL_TIE | UARTCTRL_TCIE | UARTCTRL_RIE);
2521	lpuart32_write(&sport->port, cr, UARTCTRL);
2522
2523	uart_console_write(&sport->port, s, count, lpuart32_console_putchar);
2524
2525	/* wait for transmitter finish complete and restore CR2 */
2526	lpuart32_wait_bit_set(&sport->port, UARTSTAT, UARTSTAT_TC);
2527
2528	lpuart32_write(&sport->port, old_cr, UARTCTRL);
2529
2530	if (locked)
2531		uart_port_unlock_irqrestore(&sport->port, flags);
2532}
2533
2534/*
2535 * if the port was already initialised (eg, by a boot loader),
2536 * try to determine the current setup.
2537 */
2538static void __init
2539lpuart_console_get_options(struct lpuart_port *sport, int *baud,
2540			   int *parity, int *bits)
2541{
2542	unsigned char cr, bdh, bdl, brfa;
2543	unsigned int sbr, uartclk, baud_raw;
2544
2545	cr = readb(sport->port.membase + UARTCR2);
2546	cr &= UARTCR2_TE | UARTCR2_RE;
2547	if (!cr)
2548		return;
2549
2550	/* ok, the port was enabled */
2551
2552	cr = readb(sport->port.membase + UARTCR1);
2553
2554	*parity = 'n';
2555	if (cr & UARTCR1_PE) {
2556		if (cr & UARTCR1_PT)
2557			*parity = 'o';
2558		else
2559			*parity = 'e';
2560	}
2561
2562	if (cr & UARTCR1_M)
2563		*bits = 9;
2564	else
2565		*bits = 8;
2566
2567	bdh = readb(sport->port.membase + UARTBDH);
2568	bdh &= UARTBDH_SBR_MASK;
2569	bdl = readb(sport->port.membase + UARTBDL);
2570	sbr = bdh;
2571	sbr <<= 8;
2572	sbr |= bdl;
2573	brfa = readb(sport->port.membase + UARTCR4);
2574	brfa &= UARTCR4_BRFA_MASK;
2575
2576	uartclk = lpuart_get_baud_clk_rate(sport);
2577	/*
2578	 * baud = mod_clk/(16*(sbr[13]+(brfa)/32)
2579	 */
2580	baud_raw = uartclk / (16 * (sbr + brfa / 32));
2581
2582	if (*baud != baud_raw)
2583		dev_info(sport->port.dev, "Serial: Console lpuart rounded baud rate"
2584				"from %d to %d\n", baud_raw, *baud);
2585}
2586
2587static void __init
2588lpuart32_console_get_options(struct lpuart_port *sport, int *baud,
2589			   int *parity, int *bits)
2590{
2591	unsigned long cr, bd;
2592	unsigned int sbr, uartclk, baud_raw;
2593
2594	cr = lpuart32_read(&sport->port, UARTCTRL);
2595	cr &= UARTCTRL_TE | UARTCTRL_RE;
2596	if (!cr)
2597		return;
2598
2599	/* ok, the port was enabled */
2600
2601	cr = lpuart32_read(&sport->port, UARTCTRL);
2602
2603	*parity = 'n';
2604	if (cr & UARTCTRL_PE) {
2605		if (cr & UARTCTRL_PT)
2606			*parity = 'o';
2607		else
2608			*parity = 'e';
2609	}
2610
2611	if (cr & UARTCTRL_M)
2612		*bits = 9;
2613	else
2614		*bits = 8;
2615
2616	bd = lpuart32_read(&sport->port, UARTBAUD);
2617	bd &= UARTBAUD_SBR_MASK;
2618	if (!bd)
2619		return;
2620
2621	sbr = bd;
2622	uartclk = lpuart_get_baud_clk_rate(sport);
2623	/*
2624	 * baud = mod_clk/(16*(sbr[13]+(brfa)/32)
2625	 */
2626	baud_raw = uartclk / (16 * sbr);
2627
2628	if (*baud != baud_raw)
2629		dev_info(sport->port.dev, "Serial: Console lpuart rounded baud rate"
2630				"from %d to %d\n", baud_raw, *baud);
2631}
2632
2633static int __init lpuart_console_setup(struct console *co, char *options)
2634{
2635	struct lpuart_port *sport;
2636	int baud = 115200;
2637	int bits = 8;
2638	int parity = 'n';
2639	int flow = 'n';
2640
2641	/*
2642	 * check whether an invalid uart number has been specified, and
2643	 * if so, search for the first available port that does have
2644	 * console support.
2645	 */
2646	if (co->index == -1 || co->index >= ARRAY_SIZE(lpuart_ports))
2647		co->index = 0;
2648
2649	sport = lpuart_ports[co->index];
2650	if (sport == NULL)
2651		return -ENODEV;
2652
2653	if (options)
2654		uart_parse_options(options, &baud, &parity, &bits, &flow);
2655	else
2656		if (lpuart_is_32(sport))
2657			lpuart32_console_get_options(sport, &baud, &parity, &bits);
2658		else
2659			lpuart_console_get_options(sport, &baud, &parity, &bits);
2660
2661	if (lpuart_is_32(sport))
2662		lpuart32_setup_watermark(sport);
2663	else
2664		lpuart_setup_watermark(sport);
2665
2666	return uart_set_options(&sport->port, co, baud, parity, bits, flow);
2667}
2668
2669static struct uart_driver lpuart_reg;
2670static struct console lpuart_console = {
2671	.name		= DEV_NAME,
2672	.write		= lpuart_console_write,
2673	.device		= uart_console_device,
2674	.setup		= lpuart_console_setup,
2675	.flags		= CON_PRINTBUFFER,
2676	.index		= -1,
2677	.data		= &lpuart_reg,
2678};
2679
2680static struct console lpuart32_console = {
2681	.name		= DEV_NAME,
2682	.write		= lpuart32_console_write,
2683	.device		= uart_console_device,
2684	.setup		= lpuart_console_setup,
2685	.flags		= CON_PRINTBUFFER,
2686	.index		= -1,
2687	.data		= &lpuart_reg,
2688};
2689
2690static void lpuart_early_write(struct console *con, const char *s, unsigned n)
2691{
2692	struct earlycon_device *dev = con->data;
2693
2694	uart_console_write(&dev->port, s, n, lpuart_console_putchar);
2695}
2696
2697static void lpuart32_early_write(struct console *con, const char *s, unsigned n)
2698{
2699	struct earlycon_device *dev = con->data;
2700
2701	uart_console_write(&dev->port, s, n, lpuart32_console_putchar);
2702}
2703
2704static int __init lpuart_early_console_setup(struct earlycon_device *device,
2705					  const char *opt)
2706{
2707	if (!device->port.membase)
2708		return -ENODEV;
2709
2710	device->con->write = lpuart_early_write;
2711	return 0;
2712}
2713
2714static int __init lpuart32_early_console_setup(struct earlycon_device *device,
2715					  const char *opt)
2716{
2717	if (!device->port.membase)
2718		return -ENODEV;
2719
2720	if (device->port.iotype != UPIO_MEM32)
2721		device->port.iotype = UPIO_MEM32BE;
2722
2723	device->con->write = lpuart32_early_write;
2724	return 0;
2725}
2726
2727static int __init ls1028a_early_console_setup(struct earlycon_device *device,
2728					      const char *opt)
2729{
2730	u32 cr;
2731
2732	if (!device->port.membase)
2733		return -ENODEV;
2734
2735	device->port.iotype = UPIO_MEM32;
2736	device->con->write = lpuart32_early_write;
2737
2738	/* set the baudrate */
2739	if (device->port.uartclk && device->baud)
2740		__lpuart32_serial_setbrg(&device->port, device->baud,
2741					 false, false);
2742
2743	/* enable transmitter */
2744	cr = lpuart32_read(&device->port, UARTCTRL);
2745	cr |= UARTCTRL_TE;
2746	lpuart32_write(&device->port, cr, UARTCTRL);
2747
2748	return 0;
2749}
2750
2751static int __init lpuart32_imx_early_console_setup(struct earlycon_device *device,
2752						   const char *opt)
2753{
2754	if (!device->port.membase)
2755		return -ENODEV;
2756
2757	device->port.iotype = UPIO_MEM32;
2758	device->port.membase += IMX_REG_OFF;
2759	device->con->write = lpuart32_early_write;
2760
2761	return 0;
2762}
2763OF_EARLYCON_DECLARE(lpuart, "fsl,vf610-lpuart", lpuart_early_console_setup);
2764OF_EARLYCON_DECLARE(lpuart32, "fsl,ls1021a-lpuart", lpuart32_early_console_setup);
2765OF_EARLYCON_DECLARE(lpuart32, "fsl,ls1028a-lpuart", ls1028a_early_console_setup);
2766OF_EARLYCON_DECLARE(lpuart32, "fsl,imx7ulp-lpuart", lpuart32_imx_early_console_setup);
2767OF_EARLYCON_DECLARE(lpuart32, "fsl,imx8ulp-lpuart", lpuart32_imx_early_console_setup);
2768OF_EARLYCON_DECLARE(lpuart32, "fsl,imx8qxp-lpuart", lpuart32_imx_early_console_setup);
2769OF_EARLYCON_DECLARE(lpuart32, "fsl,imxrt1050-lpuart", lpuart32_imx_early_console_setup);
2770EARLYCON_DECLARE(lpuart, lpuart_early_console_setup);
2771EARLYCON_DECLARE(lpuart32, lpuart32_early_console_setup);
2772
2773#define LPUART_CONSOLE	(&lpuart_console)
2774#define LPUART32_CONSOLE	(&lpuart32_console)
2775#else
2776#define LPUART_CONSOLE	NULL
2777#define LPUART32_CONSOLE	NULL
2778#endif
2779
2780static struct uart_driver lpuart_reg = {
2781	.owner		= THIS_MODULE,
2782	.driver_name	= DRIVER_NAME,
2783	.dev_name	= DEV_NAME,
2784	.nr		= ARRAY_SIZE(lpuart_ports),
2785	.cons		= LPUART_CONSOLE,
2786};
2787
2788static const struct serial_rs485 lpuart_rs485_supported = {
2789	.flags = SER_RS485_ENABLED | SER_RS485_RTS_ON_SEND | SER_RS485_RTS_AFTER_SEND,
2790	/* delay_rts_* and RX_DURING_TX are not supported */
2791};
2792
2793static int lpuart_global_reset(struct lpuart_port *sport)
2794{
2795	struct uart_port *port = &sport->port;
2796	void __iomem *global_addr;
2797	unsigned long ctrl, bd;
2798	unsigned int val = 0;
2799	int ret;
2800
2801	ret = clk_prepare_enable(sport->ipg_clk);
2802	if (ret) {
2803		dev_err(sport->port.dev, "failed to enable uart ipg clk: %d\n", ret);
2804		return ret;
2805	}
2806
2807	if (is_imx7ulp_lpuart(sport) || is_imx8ulp_lpuart(sport) || is_imx8qxp_lpuart(sport)) {
2808		/*
2809		 * If the transmitter is used by earlycon, wait for transmit engine to
2810		 * complete and then reset.
2811		 */
2812		ctrl = lpuart32_read(port, UARTCTRL);
2813		if (ctrl & UARTCTRL_TE) {
2814			bd = lpuart32_read(&sport->port, UARTBAUD);
2815			if (read_poll_timeout(lpuart32_tx_empty, val, val, 1, 100000, false,
2816					      port)) {
2817				dev_warn(sport->port.dev,
2818					 "timeout waiting for transmit engine to complete\n");
2819				clk_disable_unprepare(sport->ipg_clk);
2820				return 0;
2821			}
2822		}
2823
2824		global_addr = port->membase + UART_GLOBAL - IMX_REG_OFF;
2825		writel(UART_GLOBAL_RST, global_addr);
2826		usleep_range(GLOBAL_RST_MIN_US, GLOBAL_RST_MAX_US);
2827		writel(0, global_addr);
2828		usleep_range(GLOBAL_RST_MIN_US, GLOBAL_RST_MAX_US);
2829
2830		/* Recover the transmitter for earlycon. */
2831		if (ctrl & UARTCTRL_TE) {
2832			lpuart32_write(port, bd, UARTBAUD);
2833			lpuart32_write(port, ctrl, UARTCTRL);
2834		}
2835	}
2836
2837	clk_disable_unprepare(sport->ipg_clk);
2838	return 0;
2839}
2840
2841static int lpuart_probe(struct platform_device *pdev)
2842{
2843	const struct lpuart_soc_data *sdata = of_device_get_match_data(&pdev->dev);
2844	struct device_node *np = pdev->dev.of_node;
2845	struct lpuart_port *sport;
2846	struct resource *res;
2847	irq_handler_t handler;
2848	int ret;
2849
2850	sport = devm_kzalloc(&pdev->dev, sizeof(*sport), GFP_KERNEL);
2851	if (!sport)
2852		return -ENOMEM;
2853
2854	sport->port.membase = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
 
2855	if (IS_ERR(sport->port.membase))
2856		return PTR_ERR(sport->port.membase);
2857
2858	sport->port.membase += sdata->reg_off;
2859	sport->port.mapbase = res->start + sdata->reg_off;
2860	sport->port.dev = &pdev->dev;
2861	sport->port.type = PORT_LPUART;
2862	sport->devtype = sdata->devtype;
2863	sport->rx_watermark = sdata->rx_watermark;
2864	sport->dma_idle_int = is_imx7ulp_lpuart(sport) || is_imx8ulp_lpuart(sport) ||
2865			      is_imx8qxp_lpuart(sport);
2866	ret = platform_get_irq(pdev, 0);
2867	if (ret < 0)
2868		return ret;
2869	sport->port.irq = ret;
2870	sport->port.iotype = sdata->iotype;
2871	if (lpuart_is_32(sport))
2872		sport->port.ops = &lpuart32_pops;
2873	else
2874		sport->port.ops = &lpuart_pops;
2875	sport->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_FSL_LPUART_CONSOLE);
2876	sport->port.flags = UPF_BOOT_AUTOCONF;
2877
2878	if (lpuart_is_32(sport))
2879		sport->port.rs485_config = lpuart32_config_rs485;
2880	else
2881		sport->port.rs485_config = lpuart_config_rs485;
2882	sport->port.rs485_supported = lpuart_rs485_supported;
2883
2884	sport->ipg_clk = devm_clk_get(&pdev->dev, "ipg");
2885	if (IS_ERR(sport->ipg_clk)) {
2886		ret = PTR_ERR(sport->ipg_clk);
2887		dev_err(&pdev->dev, "failed to get uart ipg clk: %d\n", ret);
2888		return ret;
2889	}
2890
2891	sport->baud_clk = NULL;
2892	if (is_imx8qxp_lpuart(sport)) {
2893		sport->baud_clk = devm_clk_get(&pdev->dev, "baud");
2894		if (IS_ERR(sport->baud_clk)) {
2895			ret = PTR_ERR(sport->baud_clk);
2896			dev_err(&pdev->dev, "failed to get uart baud clk: %d\n", ret);
2897			return ret;
2898		}
2899	}
2900
2901	ret = of_alias_get_id(np, "serial");
2902	if (ret < 0) {
2903		dev_err(&pdev->dev, "failed to get alias id, errno %d\n", ret);
2904		return ret;
2905	}
2906	if (ret >= ARRAY_SIZE(lpuart_ports)) {
2907		dev_err(&pdev->dev, "serial%d out of range\n", ret);
2908		return -EINVAL;
2909	}
2910	sport->port.line = ret;
2911
2912	ret = lpuart_enable_clks(sport);
2913	if (ret)
2914		return ret;
2915	sport->port.uartclk = lpuart_get_baud_clk_rate(sport);
2916
2917	lpuart_ports[sport->port.line] = sport;
2918
2919	platform_set_drvdata(pdev, &sport->port);
2920
2921	if (lpuart_is_32(sport)) {
2922		lpuart_reg.cons = LPUART32_CONSOLE;
2923		handler = lpuart32_int;
2924	} else {
2925		lpuart_reg.cons = LPUART_CONSOLE;
2926		handler = lpuart_int;
2927	}
2928
2929	pm_runtime_use_autosuspend(&pdev->dev);
2930	pm_runtime_set_autosuspend_delay(&pdev->dev, UART_AUTOSUSPEND_TIMEOUT);
2931	pm_runtime_set_active(&pdev->dev);
2932	pm_runtime_enable(&pdev->dev);
2933
2934	ret = lpuart_global_reset(sport);
2935	if (ret)
2936		goto failed_reset;
2937
2938	ret = uart_get_rs485_mode(&sport->port);
2939	if (ret)
2940		goto failed_get_rs485;
2941
2942	ret = uart_add_one_port(&lpuart_reg, &sport->port);
2943	if (ret)
2944		goto failed_attach_port;
2945
2946	ret = devm_request_irq(&pdev->dev, sport->port.irq, handler, 0,
2947				DRIVER_NAME, sport);
2948	if (ret)
2949		goto failed_irq_request;
2950
2951	return 0;
2952
2953failed_irq_request:
2954	uart_remove_one_port(&lpuart_reg, &sport->port);
2955failed_attach_port:
2956failed_get_rs485:
2957failed_reset:
2958	pm_runtime_disable(&pdev->dev);
2959	pm_runtime_set_suspended(&pdev->dev);
2960	pm_runtime_dont_use_autosuspend(&pdev->dev);
2961	lpuart_disable_clks(sport);
2962	return ret;
2963}
2964
2965static void lpuart_remove(struct platform_device *pdev)
2966{
2967	struct lpuart_port *sport = platform_get_drvdata(pdev);
2968
2969	uart_remove_one_port(&lpuart_reg, &sport->port);
2970
2971	lpuart_disable_clks(sport);
2972
2973	if (sport->dma_tx_chan)
2974		dma_release_channel(sport->dma_tx_chan);
2975
2976	if (sport->dma_rx_chan)
2977		dma_release_channel(sport->dma_rx_chan);
2978
2979	pm_runtime_disable(&pdev->dev);
2980	pm_runtime_set_suspended(&pdev->dev);
2981	pm_runtime_dont_use_autosuspend(&pdev->dev);
 
2982}
2983
2984static int lpuart_runtime_suspend(struct device *dev)
2985{
2986	struct platform_device *pdev = to_platform_device(dev);
2987	struct lpuart_port *sport = platform_get_drvdata(pdev);
2988
2989	lpuart_disable_clks(sport);
2990
2991	return 0;
2992};
2993
2994static int lpuart_runtime_resume(struct device *dev)
2995{
2996	struct platform_device *pdev = to_platform_device(dev);
2997	struct lpuart_port *sport = platform_get_drvdata(pdev);
2998
2999	return lpuart_enable_clks(sport);
3000};
3001
3002static void serial_lpuart_enable_wakeup(struct lpuart_port *sport, bool on)
3003{
3004	unsigned int val, baud;
3005
3006	if (lpuart_is_32(sport)) {
3007		val = lpuart32_read(&sport->port, UARTCTRL);
3008		baud = lpuart32_read(&sport->port, UARTBAUD);
3009		if (on) {
3010			/* set rx_watermark to 0 in wakeup source mode */
3011			lpuart32_write(&sport->port, 0, UARTWATER);
3012			val |= UARTCTRL_RIE;
3013			/* clear RXEDGIF flag before enable RXEDGIE interrupt */
3014			lpuart32_write(&sport->port, UARTSTAT_RXEDGIF, UARTSTAT);
3015			baud |= UARTBAUD_RXEDGIE;
3016		} else {
3017			val &= ~UARTCTRL_RIE;
3018			baud &= ~UARTBAUD_RXEDGIE;
3019		}
3020		lpuart32_write(&sport->port, val, UARTCTRL);
3021		lpuart32_write(&sport->port, baud, UARTBAUD);
3022	} else {
3023		val = readb(sport->port.membase + UARTCR2);
3024		if (on)
3025			val |= UARTCR2_RIE;
3026		else
3027			val &= ~UARTCR2_RIE;
3028		writeb(val, sport->port.membase + UARTCR2);
3029	}
3030}
3031
3032static bool lpuart_uport_is_active(struct lpuart_port *sport)
3033{
3034	struct tty_port *port = &sport->port.state->port;
3035	struct tty_struct *tty;
3036	struct device *tty_dev;
3037	int may_wake = 0;
3038
3039	tty = tty_port_tty_get(port);
3040	if (tty) {
3041		tty_dev = tty->dev;
3042		may_wake = tty_dev && device_may_wakeup(tty_dev);
3043		tty_kref_put(tty);
3044	}
3045
3046	if ((tty_port_initialized(port) && may_wake) ||
3047	    (!console_suspend_enabled && uart_console(&sport->port)))
3048		return true;
3049
3050	return false;
3051}
3052
3053static int lpuart_suspend_noirq(struct device *dev)
3054{
3055	struct lpuart_port *sport = dev_get_drvdata(dev);
3056	bool irq_wake = irqd_is_wakeup_set(irq_get_irq_data(sport->port.irq));
3057
3058	if (lpuart_uport_is_active(sport))
3059		serial_lpuart_enable_wakeup(sport, !!irq_wake);
3060
3061	pinctrl_pm_select_sleep_state(dev);
3062
3063	return 0;
3064}
3065
3066static int lpuart_resume_noirq(struct device *dev)
3067{
3068	struct lpuart_port *sport = dev_get_drvdata(dev);
3069	unsigned int val;
3070
3071	pinctrl_pm_select_default_state(dev);
3072
3073	if (lpuart_uport_is_active(sport)) {
3074		serial_lpuart_enable_wakeup(sport, false);
3075
3076		/* clear the wakeup flags */
3077		if (lpuart_is_32(sport)) {
3078			val = lpuart32_read(&sport->port, UARTSTAT);
3079			lpuart32_write(&sport->port, val, UARTSTAT);
3080		}
3081	}
3082
3083	return 0;
3084}
3085
3086static int lpuart_suspend(struct device *dev)
3087{
3088	struct lpuart_port *sport = dev_get_drvdata(dev);
3089	unsigned long temp, flags;
3090
3091	uart_suspend_port(&lpuart_reg, &sport->port);
3092
3093	if (lpuart_uport_is_active(sport)) {
3094		uart_port_lock_irqsave(&sport->port, &flags);
3095		if (lpuart_is_32(sport)) {
3096			/* disable Rx/Tx and interrupts */
3097			temp = lpuart32_read(&sport->port, UARTCTRL);
3098			temp &= ~(UARTCTRL_TE | UARTCTRL_TIE | UARTCTRL_TCIE);
3099			lpuart32_write(&sport->port, temp, UARTCTRL);
3100		} else {
3101			/* disable Rx/Tx and interrupts */
3102			temp = readb(sport->port.membase + UARTCR2);
3103			temp &= ~(UARTCR2_TE | UARTCR2_TIE | UARTCR2_TCIE);
3104			writeb(temp, sport->port.membase + UARTCR2);
3105		}
3106		uart_port_unlock_irqrestore(&sport->port, flags);
3107
3108		if (sport->lpuart_dma_rx_use) {
3109			/*
3110			 * EDMA driver during suspend will forcefully release any
3111			 * non-idle DMA channels. If port wakeup is enabled or if port
3112			 * is console port or 'no_console_suspend' is set the Rx DMA
3113			 * cannot resume as expected, hence gracefully release the
3114			 * Rx DMA path before suspend and start Rx DMA path on resume.
3115			 */
 
3116			lpuart_dma_rx_free(&sport->port);
3117
3118			/* Disable Rx DMA to use UART port as wakeup source */
3119			uart_port_lock_irqsave(&sport->port, &flags);
3120			if (lpuart_is_32(sport)) {
3121				temp = lpuart32_read(&sport->port, UARTBAUD);
3122				lpuart32_write(&sport->port, temp & ~UARTBAUD_RDMAE,
3123					       UARTBAUD);
3124			} else {
3125				writeb(readb(sport->port.membase + UARTCR5) &
3126				       ~UARTCR5_RDMAS, sport->port.membase + UARTCR5);
3127			}
3128			uart_port_unlock_irqrestore(&sport->port, flags);
3129		}
3130
3131		if (sport->lpuart_dma_tx_use) {
3132			uart_port_lock_irqsave(&sport->port, &flags);
3133			if (lpuart_is_32(sport)) {
3134				temp = lpuart32_read(&sport->port, UARTBAUD);
3135				temp &= ~UARTBAUD_TDMAE;
3136				lpuart32_write(&sport->port, temp, UARTBAUD);
3137			} else {
3138				temp = readb(sport->port.membase + UARTCR5);
3139				temp &= ~UARTCR5_TDMAS;
3140				writeb(temp, sport->port.membase + UARTCR5);
3141			}
3142			uart_port_unlock_irqrestore(&sport->port, flags);
3143			sport->dma_tx_in_progress = false;
3144			dmaengine_terminate_sync(sport->dma_tx_chan);
3145		}
3146	} else if (pm_runtime_active(sport->port.dev)) {
3147		lpuart_disable_clks(sport);
3148		pm_runtime_disable(sport->port.dev);
3149		pm_runtime_set_suspended(sport->port.dev);
3150	}
3151
3152	return 0;
3153}
3154
3155static void lpuart_console_fixup(struct lpuart_port *sport)
3156{
3157	struct tty_port *port = &sport->port.state->port;
3158	struct uart_port *uport = &sport->port;
3159	struct ktermios termios;
3160
3161	/* i.MX7ULP enter VLLS mode that lpuart module power off and registers
3162	 * all lost no matter the port is wakeup source.
3163	 * For console port, console baud rate setting lost and print messy
3164	 * log when enable the console port as wakeup source. To avoid the
3165	 * issue happen, user should not enable uart port as wakeup source
3166	 * in VLLS mode, or restore console setting here.
3167	 */
3168	if (is_imx7ulp_lpuart(sport) && lpuart_uport_is_active(sport) &&
3169	    console_suspend_enabled && uart_console(&sport->port)) {
3170
3171		mutex_lock(&port->mutex);
3172		memset(&termios, 0, sizeof(struct ktermios));
3173		termios.c_cflag = uport->cons->cflag;
3174		if (port->tty && termios.c_cflag == 0)
3175			termios = port->tty->termios;
3176		uport->ops->set_termios(uport, &termios, NULL);
3177		mutex_unlock(&port->mutex);
3178	}
3179}
3180
3181static int lpuart_resume(struct device *dev)
3182{
3183	struct lpuart_port *sport = dev_get_drvdata(dev);
3184	int ret;
3185
3186	if (lpuart_uport_is_active(sport)) {
3187		if (lpuart_is_32(sport))
3188			lpuart32_hw_setup(sport);
3189		else
3190			lpuart_hw_setup(sport);
3191	} else if (pm_runtime_active(sport->port.dev)) {
3192		ret = lpuart_enable_clks(sport);
3193		if (ret)
3194			return ret;
3195		pm_runtime_set_active(sport->port.dev);
3196		pm_runtime_enable(sport->port.dev);
3197	}
3198
3199	lpuart_console_fixup(sport);
3200	uart_resume_port(&lpuart_reg, &sport->port);
3201
3202	return 0;
3203}
3204
3205static const struct dev_pm_ops lpuart_pm_ops = {
3206	RUNTIME_PM_OPS(lpuart_runtime_suspend,
3207			   lpuart_runtime_resume, NULL)
3208	NOIRQ_SYSTEM_SLEEP_PM_OPS(lpuart_suspend_noirq,
3209				      lpuart_resume_noirq)
3210	SYSTEM_SLEEP_PM_OPS(lpuart_suspend, lpuart_resume)
3211};
3212
3213static struct platform_driver lpuart_driver = {
3214	.probe		= lpuart_probe,
3215	.remove_new	= lpuart_remove,
3216	.driver		= {
3217		.name	= "fsl-lpuart",
3218		.of_match_table = lpuart_dt_ids,
3219		.pm	= pm_ptr(&lpuart_pm_ops),
3220	},
3221};
3222
3223static int __init lpuart_serial_init(void)
3224{
3225	int ret = uart_register_driver(&lpuart_reg);
3226
3227	if (ret)
3228		return ret;
3229
3230	ret = platform_driver_register(&lpuart_driver);
3231	if (ret)
3232		uart_unregister_driver(&lpuart_reg);
3233
3234	return ret;
3235}
3236
3237static void __exit lpuart_serial_exit(void)
3238{
3239	platform_driver_unregister(&lpuart_driver);
3240	uart_unregister_driver(&lpuart_reg);
3241}
3242
3243module_init(lpuart_serial_init);
3244module_exit(lpuart_serial_exit);
3245
3246MODULE_DESCRIPTION("Freescale lpuart serial port driver");
3247MODULE_LICENSE("GPL v2");
v6.2
   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 *  Freescale lpuart serial port driver
   4 *
   5 *  Copyright 2012-2014 Freescale Semiconductor, Inc.
   6 */
   7
 
 
   8#include <linux/clk.h>
   9#include <linux/console.h>
  10#include <linux/delay.h>
  11#include <linux/dma-mapping.h>
  12#include <linux/dmaengine.h>
  13#include <linux/dmapool.h>
  14#include <linux/io.h>
  15#include <linux/iopoll.h>
  16#include <linux/irq.h>
  17#include <linux/module.h>
  18#include <linux/of.h>
  19#include <linux/of_device.h>
  20#include <linux/of_dma.h>
  21#include <linux/pinctrl/consumer.h>
 
  22#include <linux/pm_runtime.h>
  23#include <linux/serial_core.h>
  24#include <linux/slab.h>
  25#include <linux/tty_flip.h>
  26
  27/* All registers are 8-bit width */
  28#define UARTBDH			0x00
  29#define UARTBDL			0x01
  30#define UARTCR1			0x02
  31#define UARTCR2			0x03
  32#define UARTSR1			0x04
  33#define UARTCR3			0x06
  34#define UARTDR			0x07
  35#define UARTCR4			0x0a
  36#define UARTCR5			0x0b
  37#define UARTMODEM		0x0d
  38#define UARTPFIFO		0x10
  39#define UARTCFIFO		0x11
  40#define UARTSFIFO		0x12
  41#define UARTTWFIFO		0x13
  42#define UARTTCFIFO		0x14
  43#define UARTRWFIFO		0x15
  44
  45#define UARTBDH_LBKDIE		0x80
  46#define UARTBDH_RXEDGIE		0x40
  47#define UARTBDH_SBR_MASK	0x1f
  48
  49#define UARTCR1_LOOPS		0x80
  50#define UARTCR1_RSRC		0x20
  51#define UARTCR1_M		0x10
  52#define UARTCR1_WAKE		0x08
  53#define UARTCR1_ILT		0x04
  54#define UARTCR1_PE		0x02
  55#define UARTCR1_PT		0x01
  56
  57#define UARTCR2_TIE		0x80
  58#define UARTCR2_TCIE		0x40
  59#define UARTCR2_RIE		0x20
  60#define UARTCR2_ILIE		0x10
  61#define UARTCR2_TE		0x08
  62#define UARTCR2_RE		0x04
  63#define UARTCR2_RWU		0x02
  64#define UARTCR2_SBK		0x01
  65
  66#define UARTSR1_TDRE		0x80
  67#define UARTSR1_TC		0x40
  68#define UARTSR1_RDRF		0x20
  69#define UARTSR1_IDLE		0x10
  70#define UARTSR1_OR		0x08
  71#define UARTSR1_NF		0x04
  72#define UARTSR1_FE		0x02
  73#define UARTSR1_PE		0x01
  74
  75#define UARTCR3_R8		0x80
  76#define UARTCR3_T8		0x40
  77#define UARTCR3_TXDIR		0x20
  78#define UARTCR3_TXINV		0x10
  79#define UARTCR3_ORIE		0x08
  80#define UARTCR3_NEIE		0x04
  81#define UARTCR3_FEIE		0x02
  82#define UARTCR3_PEIE		0x01
  83
  84#define UARTCR4_MAEN1		0x80
  85#define UARTCR4_MAEN2		0x40
  86#define UARTCR4_M10		0x20
  87#define UARTCR4_BRFA_MASK	0x1f
  88#define UARTCR4_BRFA_OFF	0
  89
  90#define UARTCR5_TDMAS		0x80
  91#define UARTCR5_RDMAS		0x20
  92
  93#define UARTMODEM_RXRTSE	0x08
  94#define UARTMODEM_TXRTSPOL	0x04
  95#define UARTMODEM_TXRTSE	0x02
  96#define UARTMODEM_TXCTSE	0x01
  97
  98#define UARTPFIFO_TXFE		0x80
  99#define UARTPFIFO_FIFOSIZE_MASK	0x7
 100#define UARTPFIFO_TXSIZE_OFF	4
 101#define UARTPFIFO_RXFE		0x08
 102#define UARTPFIFO_RXSIZE_OFF	0
 103
 104#define UARTCFIFO_TXFLUSH	0x80
 105#define UARTCFIFO_RXFLUSH	0x40
 106#define UARTCFIFO_RXOFE		0x04
 107#define UARTCFIFO_TXOFE		0x02
 108#define UARTCFIFO_RXUFE		0x01
 109
 110#define UARTSFIFO_TXEMPT	0x80
 111#define UARTSFIFO_RXEMPT	0x40
 112#define UARTSFIFO_RXOF		0x04
 113#define UARTSFIFO_TXOF		0x02
 114#define UARTSFIFO_RXUF		0x01
 115
 116/* 32-bit global registers only for i.MX7ULP/i.MX8x
 117 * Used to reset all internal logic and registers, except the Global Register.
 118 */
 119#define UART_GLOBAL		0x8
 120
 121/* 32-bit register definition */
 122#define UARTBAUD		0x00
 123#define UARTSTAT		0x04
 124#define UARTCTRL		0x08
 125#define UARTDATA		0x0C
 126#define UARTMATCH		0x10
 127#define UARTMODIR		0x14
 128#define UARTFIFO		0x18
 129#define UARTWATER		0x1c
 130
 131#define UARTBAUD_MAEN1		0x80000000
 132#define UARTBAUD_MAEN2		0x40000000
 133#define UARTBAUD_M10		0x20000000
 134#define UARTBAUD_TDMAE		0x00800000
 135#define UARTBAUD_RDMAE		0x00200000
 136#define UARTBAUD_MATCFG		0x00400000
 137#define UARTBAUD_BOTHEDGE	0x00020000
 138#define UARTBAUD_RESYNCDIS	0x00010000
 139#define UARTBAUD_LBKDIE		0x00008000
 140#define UARTBAUD_RXEDGIE	0x00004000
 141#define UARTBAUD_SBNS		0x00002000
 142#define UARTBAUD_SBR		0x00000000
 143#define UARTBAUD_SBR_MASK	0x1fff
 144#define UARTBAUD_OSR_MASK       0x1f
 145#define UARTBAUD_OSR_SHIFT      24
 146
 147#define UARTSTAT_LBKDIF		0x80000000
 148#define UARTSTAT_RXEDGIF	0x40000000
 149#define UARTSTAT_MSBF		0x20000000
 150#define UARTSTAT_RXINV		0x10000000
 151#define UARTSTAT_RWUID		0x08000000
 152#define UARTSTAT_BRK13		0x04000000
 153#define UARTSTAT_LBKDE		0x02000000
 154#define UARTSTAT_RAF		0x01000000
 155#define UARTSTAT_TDRE		0x00800000
 156#define UARTSTAT_TC		0x00400000
 157#define UARTSTAT_RDRF		0x00200000
 158#define UARTSTAT_IDLE		0x00100000
 159#define UARTSTAT_OR		0x00080000
 160#define UARTSTAT_NF		0x00040000
 161#define UARTSTAT_FE		0x00020000
 162#define UARTSTAT_PE		0x00010000
 163#define UARTSTAT_MA1F		0x00008000
 164#define UARTSTAT_M21F		0x00004000
 165
 166#define UARTCTRL_R8T9		0x80000000
 167#define UARTCTRL_R9T8		0x40000000
 168#define UARTCTRL_TXDIR		0x20000000
 169#define UARTCTRL_TXINV		0x10000000
 170#define UARTCTRL_ORIE		0x08000000
 171#define UARTCTRL_NEIE		0x04000000
 172#define UARTCTRL_FEIE		0x02000000
 173#define UARTCTRL_PEIE		0x01000000
 174#define UARTCTRL_TIE		0x00800000
 175#define UARTCTRL_TCIE		0x00400000
 176#define UARTCTRL_RIE		0x00200000
 177#define UARTCTRL_ILIE		0x00100000
 178#define UARTCTRL_TE		0x00080000
 179#define UARTCTRL_RE		0x00040000
 180#define UARTCTRL_RWU		0x00020000
 181#define UARTCTRL_SBK		0x00010000
 182#define UARTCTRL_MA1IE		0x00008000
 183#define UARTCTRL_MA2IE		0x00004000
 184#define UARTCTRL_IDLECFG	0x00000100
 185#define UARTCTRL_LOOPS		0x00000080
 186#define UARTCTRL_DOZEEN		0x00000040
 187#define UARTCTRL_RSRC		0x00000020
 188#define UARTCTRL_M		0x00000010
 189#define UARTCTRL_WAKE		0x00000008
 190#define UARTCTRL_ILT		0x00000004
 191#define UARTCTRL_PE		0x00000002
 192#define UARTCTRL_PT		0x00000001
 193
 194#define UARTDATA_NOISY		0x00008000
 195#define UARTDATA_PARITYE	0x00004000
 196#define UARTDATA_FRETSC		0x00002000
 197#define UARTDATA_RXEMPT		0x00001000
 198#define UARTDATA_IDLINE		0x00000800
 199#define UARTDATA_MASK		0x3ff
 200
 201#define UARTMODIR_IREN		0x00020000
 
 202#define UARTMODIR_TXCTSSRC	0x00000020
 203#define UARTMODIR_TXCTSC	0x00000010
 204#define UARTMODIR_RXRTSE	0x00000008
 205#define UARTMODIR_TXRTSPOL	0x00000004
 206#define UARTMODIR_TXRTSE	0x00000002
 207#define UARTMODIR_TXCTSE	0x00000001
 208
 209#define UARTFIFO_TXEMPT		0x00800000
 210#define UARTFIFO_RXEMPT		0x00400000
 211#define UARTFIFO_TXOF		0x00020000
 212#define UARTFIFO_RXUF		0x00010000
 213#define UARTFIFO_TXFLUSH	0x00008000
 214#define UARTFIFO_RXFLUSH	0x00004000
 
 215#define UARTFIFO_TXOFE		0x00000200
 216#define UARTFIFO_RXUFE		0x00000100
 217#define UARTFIFO_TXFE		0x00000080
 218#define UARTFIFO_FIFOSIZE_MASK	0x7
 219#define UARTFIFO_TXSIZE_OFF	4
 220#define UARTFIFO_RXFE		0x00000008
 221#define UARTFIFO_RXSIZE_OFF	0
 222#define UARTFIFO_DEPTH(x)	(0x1 << ((x) ? ((x) + 1) : 0))
 223
 224#define UARTWATER_COUNT_MASK	0xff
 225#define UARTWATER_TXCNT_OFF	8
 226#define UARTWATER_RXCNT_OFF	24
 227#define UARTWATER_WATER_MASK	0xff
 228#define UARTWATER_TXWATER_OFF	0
 229#define UARTWATER_RXWATER_OFF	16
 230
 231#define UART_GLOBAL_RST	0x2
 232#define GLOBAL_RST_MIN_US	20
 233#define GLOBAL_RST_MAX_US	40
 234
 235/* Rx DMA timeout in ms, which is used to calculate Rx ring buffer size */
 236#define DMA_RX_TIMEOUT		(10)
 
 237#define UART_AUTOSUSPEND_TIMEOUT	3000
 238
 239#define DRIVER_NAME	"fsl-lpuart"
 240#define DEV_NAME	"ttyLP"
 241#define UART_NR		6
 242
 243/* IMX lpuart has four extra unused regs located at the beginning */
 244#define IMX_REG_OFF	0x10
 245
 246enum lpuart_type {
 247	VF610_LPUART,
 248	LS1021A_LPUART,
 249	LS1028A_LPUART,
 250	IMX7ULP_LPUART,
 
 251	IMX8QXP_LPUART,
 252	IMXRT1050_LPUART,
 253};
 254
 255struct lpuart_port {
 256	struct uart_port	port;
 257	enum lpuart_type	devtype;
 258	struct clk		*ipg_clk;
 259	struct clk		*baud_clk;
 260	unsigned int		txfifo_size;
 261	unsigned int		rxfifo_size;
 262
 
 263	bool			lpuart_dma_tx_use;
 264	bool			lpuart_dma_rx_use;
 265	struct dma_chan		*dma_tx_chan;
 266	struct dma_chan		*dma_rx_chan;
 267	struct dma_async_tx_descriptor  *dma_tx_desc;
 268	struct dma_async_tx_descriptor  *dma_rx_desc;
 269	dma_cookie_t		dma_tx_cookie;
 270	dma_cookie_t		dma_rx_cookie;
 271	unsigned int		dma_tx_bytes;
 272	unsigned int		dma_rx_bytes;
 273	bool			dma_tx_in_progress;
 274	unsigned int		dma_rx_timeout;
 275	struct timer_list	lpuart_timer;
 276	struct scatterlist	rx_sgl, tx_sgl[2];
 277	struct circ_buf		rx_ring;
 278	int			rx_dma_rng_buf_len;
 
 279	unsigned int		dma_tx_nents;
 280	wait_queue_head_t	dma_wait;
 281	bool			is_cs7; /* Set to true when character size is 7 */
 282					/* and the parity is enabled		*/
 
 283};
 284
 285struct lpuart_soc_data {
 286	enum lpuart_type devtype;
 287	char iotype;
 288	u8 reg_off;
 
 289};
 290
 291static const struct lpuart_soc_data vf_data = {
 292	.devtype = VF610_LPUART,
 293	.iotype = UPIO_MEM,
 
 294};
 295
 296static const struct lpuart_soc_data ls1021a_data = {
 297	.devtype = LS1021A_LPUART,
 298	.iotype = UPIO_MEM32BE,
 
 299};
 300
 301static const struct lpuart_soc_data ls1028a_data = {
 302	.devtype = LS1028A_LPUART,
 303	.iotype = UPIO_MEM32,
 
 304};
 305
 306static struct lpuart_soc_data imx7ulp_data = {
 307	.devtype = IMX7ULP_LPUART,
 308	.iotype = UPIO_MEM32,
 309	.reg_off = IMX_REG_OFF,
 
 
 
 
 
 
 
 
 310};
 311
 312static struct lpuart_soc_data imx8qxp_data = {
 313	.devtype = IMX8QXP_LPUART,
 314	.iotype = UPIO_MEM32,
 315	.reg_off = IMX_REG_OFF,
 
 316};
 317static struct lpuart_soc_data imxrt1050_data = {
 318	.devtype = IMXRT1050_LPUART,
 319	.iotype = UPIO_MEM32,
 320	.reg_off = IMX_REG_OFF,
 
 321};
 322
 323static const struct of_device_id lpuart_dt_ids[] = {
 324	{ .compatible = "fsl,vf610-lpuart",	.data = &vf_data, },
 325	{ .compatible = "fsl,ls1021a-lpuart",	.data = &ls1021a_data, },
 326	{ .compatible = "fsl,ls1028a-lpuart",	.data = &ls1028a_data, },
 327	{ .compatible = "fsl,imx7ulp-lpuart",	.data = &imx7ulp_data, },
 
 328	{ .compatible = "fsl,imx8qxp-lpuart",	.data = &imx8qxp_data, },
 329	{ .compatible = "fsl,imxrt1050-lpuart",	.data = &imxrt1050_data},
 330	{ /* sentinel */ }
 331};
 332MODULE_DEVICE_TABLE(of, lpuart_dt_ids);
 333
 334/* Forward declare this for the dma callbacks*/
 335static void lpuart_dma_tx_complete(void *arg);
 336
 337static inline bool is_layerscape_lpuart(struct lpuart_port *sport)
 338{
 339	return (sport->devtype == LS1021A_LPUART ||
 340		sport->devtype == LS1028A_LPUART);
 341}
 342
 343static inline bool is_imx7ulp_lpuart(struct lpuart_port *sport)
 344{
 345	return sport->devtype == IMX7ULP_LPUART;
 346}
 347
 
 
 
 
 
 348static inline bool is_imx8qxp_lpuart(struct lpuart_port *sport)
 349{
 350	return sport->devtype == IMX8QXP_LPUART;
 351}
 352
 353static inline u32 lpuart32_read(struct uart_port *port, u32 off)
 354{
 355	switch (port->iotype) {
 356	case UPIO_MEM32:
 357		return readl(port->membase + off);
 358	case UPIO_MEM32BE:
 359		return ioread32be(port->membase + off);
 360	default:
 361		return 0;
 362	}
 363}
 364
 365static inline void lpuart32_write(struct uart_port *port, u32 val,
 366				  u32 off)
 367{
 368	switch (port->iotype) {
 369	case UPIO_MEM32:
 370		writel(val, port->membase + off);
 371		break;
 372	case UPIO_MEM32BE:
 373		iowrite32be(val, port->membase + off);
 374		break;
 375	}
 376}
 377
 378static int __lpuart_enable_clks(struct lpuart_port *sport, bool is_en)
 379{
 380	int ret = 0;
 381
 382	if (is_en) {
 383		ret = clk_prepare_enable(sport->ipg_clk);
 384		if (ret)
 385			return ret;
 386
 387		ret = clk_prepare_enable(sport->baud_clk);
 388		if (ret) {
 389			clk_disable_unprepare(sport->ipg_clk);
 390			return ret;
 391		}
 392	} else {
 393		clk_disable_unprepare(sport->baud_clk);
 394		clk_disable_unprepare(sport->ipg_clk);
 395	}
 396
 397	return 0;
 398}
 399
 400static unsigned int lpuart_get_baud_clk_rate(struct lpuart_port *sport)
 401{
 402	if (is_imx8qxp_lpuart(sport))
 403		return clk_get_rate(sport->baud_clk);
 404
 405	return clk_get_rate(sport->ipg_clk);
 406}
 407
 408#define lpuart_enable_clks(x)	__lpuart_enable_clks(x, true)
 409#define lpuart_disable_clks(x)	__lpuart_enable_clks(x, false)
 410
 411static void lpuart_stop_tx(struct uart_port *port)
 412{
 413	unsigned char temp;
 414
 415	temp = readb(port->membase + UARTCR2);
 416	temp &= ~(UARTCR2_TIE | UARTCR2_TCIE);
 417	writeb(temp, port->membase + UARTCR2);
 418}
 419
 420static void lpuart32_stop_tx(struct uart_port *port)
 421{
 422	unsigned long temp;
 423
 424	temp = lpuart32_read(port, UARTCTRL);
 425	temp &= ~(UARTCTRL_TIE | UARTCTRL_TCIE);
 426	lpuart32_write(port, temp, UARTCTRL);
 427}
 428
 429static void lpuart_stop_rx(struct uart_port *port)
 430{
 431	unsigned char temp;
 432
 433	temp = readb(port->membase + UARTCR2);
 434	writeb(temp & ~UARTCR2_RE, port->membase + UARTCR2);
 435}
 436
 437static void lpuart32_stop_rx(struct uart_port *port)
 438{
 439	unsigned long temp;
 440
 441	temp = lpuart32_read(port, UARTCTRL);
 442	lpuart32_write(port, temp & ~UARTCTRL_RE, UARTCTRL);
 443}
 444
 445static void lpuart_dma_tx(struct lpuart_port *sport)
 446{
 447	struct circ_buf *xmit = &sport->port.state->xmit;
 448	struct scatterlist *sgl = sport->tx_sgl;
 449	struct device *dev = sport->port.dev;
 450	struct dma_chan *chan = sport->dma_tx_chan;
 451	int ret;
 452
 453	if (sport->dma_tx_in_progress)
 454		return;
 455
 456	sport->dma_tx_bytes = uart_circ_chars_pending(xmit);
 457
 458	if (xmit->tail < xmit->head || xmit->head == 0) {
 459		sport->dma_tx_nents = 1;
 460		sg_init_one(sgl, xmit->buf + xmit->tail, sport->dma_tx_bytes);
 461	} else {
 462		sport->dma_tx_nents = 2;
 463		sg_init_table(sgl, 2);
 464		sg_set_buf(sgl, xmit->buf + xmit->tail,
 465				UART_XMIT_SIZE - xmit->tail);
 466		sg_set_buf(sgl + 1, xmit->buf, xmit->head);
 467	}
 468
 469	ret = dma_map_sg(chan->device->dev, sgl, sport->dma_tx_nents,
 470			 DMA_TO_DEVICE);
 471	if (!ret) {
 472		dev_err(dev, "DMA mapping error for TX.\n");
 473		return;
 474	}
 475
 476	sport->dma_tx_desc = dmaengine_prep_slave_sg(chan, sgl,
 477					ret, DMA_MEM_TO_DEV,
 478					DMA_PREP_INTERRUPT);
 479	if (!sport->dma_tx_desc) {
 480		dma_unmap_sg(chan->device->dev, sgl, sport->dma_tx_nents,
 481			      DMA_TO_DEVICE);
 482		dev_err(dev, "Cannot prepare TX slave DMA!\n");
 483		return;
 484	}
 485
 486	sport->dma_tx_desc->callback = lpuart_dma_tx_complete;
 487	sport->dma_tx_desc->callback_param = sport;
 488	sport->dma_tx_in_progress = true;
 489	sport->dma_tx_cookie = dmaengine_submit(sport->dma_tx_desc);
 490	dma_async_issue_pending(chan);
 491}
 492
 493static bool lpuart_stopped_or_empty(struct uart_port *port)
 494{
 495	return uart_circ_empty(&port->state->xmit) || uart_tx_stopped(port);
 496}
 497
 498static void lpuart_dma_tx_complete(void *arg)
 499{
 500	struct lpuart_port *sport = arg;
 501	struct scatterlist *sgl = &sport->tx_sgl[0];
 502	struct circ_buf *xmit = &sport->port.state->xmit;
 503	struct dma_chan *chan = sport->dma_tx_chan;
 504	unsigned long flags;
 505
 506	spin_lock_irqsave(&sport->port.lock, flags);
 507	if (!sport->dma_tx_in_progress) {
 508		spin_unlock_irqrestore(&sport->port.lock, flags);
 509		return;
 510	}
 511
 512	dma_unmap_sg(chan->device->dev, sgl, sport->dma_tx_nents,
 513		     DMA_TO_DEVICE);
 514
 515	uart_xmit_advance(&sport->port, sport->dma_tx_bytes);
 516	sport->dma_tx_in_progress = false;
 517	spin_unlock_irqrestore(&sport->port.lock, flags);
 518
 519	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 520		uart_write_wakeup(&sport->port);
 521
 522	if (waitqueue_active(&sport->dma_wait)) {
 523		wake_up(&sport->dma_wait);
 524		return;
 525	}
 526
 527	spin_lock_irqsave(&sport->port.lock, flags);
 528
 529	if (!lpuart_stopped_or_empty(&sport->port))
 530		lpuart_dma_tx(sport);
 531
 532	spin_unlock_irqrestore(&sport->port.lock, flags);
 533}
 534
 535static dma_addr_t lpuart_dma_datareg_addr(struct lpuart_port *sport)
 536{
 537	switch (sport->port.iotype) {
 538	case UPIO_MEM32:
 539		return sport->port.mapbase + UARTDATA;
 540	case UPIO_MEM32BE:
 541		return sport->port.mapbase + UARTDATA + sizeof(u32) - 1;
 542	}
 543	return sport->port.mapbase + UARTDR;
 544}
 545
 546static int lpuart_dma_tx_request(struct uart_port *port)
 547{
 548	struct lpuart_port *sport = container_of(port,
 549					struct lpuart_port, port);
 550	struct dma_slave_config dma_tx_sconfig = {};
 551	int ret;
 552
 553	dma_tx_sconfig.dst_addr = lpuart_dma_datareg_addr(sport);
 554	dma_tx_sconfig.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
 555	dma_tx_sconfig.dst_maxburst = 1;
 556	dma_tx_sconfig.direction = DMA_MEM_TO_DEV;
 557	ret = dmaengine_slave_config(sport->dma_tx_chan, &dma_tx_sconfig);
 558
 559	if (ret) {
 560		dev_err(sport->port.dev,
 561				"DMA slave config failed, err = %d\n", ret);
 562		return ret;
 563	}
 564
 565	return 0;
 566}
 567
 568static bool lpuart_is_32(struct lpuart_port *sport)
 569{
 570	return sport->port.iotype == UPIO_MEM32 ||
 571	       sport->port.iotype ==  UPIO_MEM32BE;
 572}
 573
 574static void lpuart_flush_buffer(struct uart_port *port)
 575{
 576	struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
 577	struct dma_chan *chan = sport->dma_tx_chan;
 578	u32 val;
 579
 580	if (sport->lpuart_dma_tx_use) {
 581		if (sport->dma_tx_in_progress) {
 582			dma_unmap_sg(chan->device->dev, &sport->tx_sgl[0],
 583				sport->dma_tx_nents, DMA_TO_DEVICE);
 584			sport->dma_tx_in_progress = false;
 585		}
 586		dmaengine_terminate_async(chan);
 587	}
 588
 589	if (lpuart_is_32(sport)) {
 590		val = lpuart32_read(&sport->port, UARTFIFO);
 591		val |= UARTFIFO_TXFLUSH | UARTFIFO_RXFLUSH;
 592		lpuart32_write(&sport->port, val, UARTFIFO);
 593	} else {
 594		val = readb(sport->port.membase + UARTCFIFO);
 595		val |= UARTCFIFO_TXFLUSH | UARTCFIFO_RXFLUSH;
 596		writeb(val, sport->port.membase + UARTCFIFO);
 597	}
 598}
 599
 600static void lpuart_wait_bit_set(struct uart_port *port, unsigned int offset,
 601				u8 bit)
 602{
 603	while (!(readb(port->membase + offset) & bit))
 604		cpu_relax();
 605}
 606
 607static void lpuart32_wait_bit_set(struct uart_port *port, unsigned int offset,
 608				  u32 bit)
 609{
 610	while (!(lpuart32_read(port, offset) & bit))
 611		cpu_relax();
 612}
 613
 614#if defined(CONFIG_CONSOLE_POLL)
 615
 616static int lpuart_poll_init(struct uart_port *port)
 617{
 618	struct lpuart_port *sport = container_of(port,
 619					struct lpuart_port, port);
 620	unsigned long flags;
 621	unsigned char temp;
 622
 623	sport->port.fifosize = 0;
 624
 625	spin_lock_irqsave(&sport->port.lock, flags);
 626	/* Disable Rx & Tx */
 627	writeb(0, sport->port.membase + UARTCR2);
 628
 629	temp = readb(sport->port.membase + UARTPFIFO);
 630	/* Enable Rx and Tx FIFO */
 631	writeb(temp | UARTPFIFO_RXFE | UARTPFIFO_TXFE,
 632			sport->port.membase + UARTPFIFO);
 633
 634	/* flush Tx and Rx FIFO */
 635	writeb(UARTCFIFO_TXFLUSH | UARTCFIFO_RXFLUSH,
 636			sport->port.membase + UARTCFIFO);
 637
 638	/* explicitly clear RDRF */
 639	if (readb(sport->port.membase + UARTSR1) & UARTSR1_RDRF) {
 640		readb(sport->port.membase + UARTDR);
 641		writeb(UARTSFIFO_RXUF, sport->port.membase + UARTSFIFO);
 642	}
 643
 644	writeb(0, sport->port.membase + UARTTWFIFO);
 645	writeb(1, sport->port.membase + UARTRWFIFO);
 646
 647	/* Enable Rx and Tx */
 648	writeb(UARTCR2_RE | UARTCR2_TE, sport->port.membase + UARTCR2);
 649	spin_unlock_irqrestore(&sport->port.lock, flags);
 650
 651	return 0;
 652}
 653
 654static void lpuart_poll_put_char(struct uart_port *port, unsigned char c)
 655{
 656	/* drain */
 657	lpuart_wait_bit_set(port, UARTSR1, UARTSR1_TDRE);
 658	writeb(c, port->membase + UARTDR);
 659}
 660
 661static int lpuart_poll_get_char(struct uart_port *port)
 662{
 663	if (!(readb(port->membase + UARTSR1) & UARTSR1_RDRF))
 664		return NO_POLL_CHAR;
 665
 666	return readb(port->membase + UARTDR);
 667}
 668
 669static int lpuart32_poll_init(struct uart_port *port)
 670{
 671	unsigned long flags;
 672	struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
 673	u32 temp;
 674
 675	sport->port.fifosize = 0;
 676
 677	spin_lock_irqsave(&sport->port.lock, flags);
 678
 679	/* Disable Rx & Tx */
 680	lpuart32_write(&sport->port, 0, UARTCTRL);
 681
 682	temp = lpuart32_read(&sport->port, UARTFIFO);
 683
 684	/* Enable Rx and Tx FIFO */
 685	lpuart32_write(&sport->port, temp | UARTFIFO_RXFE | UARTFIFO_TXFE, UARTFIFO);
 686
 687	/* flush Tx and Rx FIFO */
 688	lpuart32_write(&sport->port, UARTFIFO_TXFLUSH | UARTFIFO_RXFLUSH, UARTFIFO);
 689
 690	/* explicitly clear RDRF */
 691	if (lpuart32_read(&sport->port, UARTSTAT) & UARTSTAT_RDRF) {
 692		lpuart32_read(&sport->port, UARTDATA);
 693		lpuart32_write(&sport->port, UARTFIFO_RXUF, UARTFIFO);
 694	}
 695
 696	/* Enable Rx and Tx */
 697	lpuart32_write(&sport->port, UARTCTRL_RE | UARTCTRL_TE, UARTCTRL);
 698	spin_unlock_irqrestore(&sport->port.lock, flags);
 699
 700	return 0;
 701}
 702
 703static void lpuart32_poll_put_char(struct uart_port *port, unsigned char c)
 704{
 705	lpuart32_wait_bit_set(port, UARTSTAT, UARTSTAT_TDRE);
 706	lpuart32_write(port, c, UARTDATA);
 707}
 708
 709static int lpuart32_poll_get_char(struct uart_port *port)
 710{
 711	if (!(lpuart32_read(port, UARTWATER) >> UARTWATER_RXCNT_OFF))
 712		return NO_POLL_CHAR;
 713
 714	return lpuart32_read(port, UARTDATA);
 715}
 716#endif
 717
 718static inline void lpuart_transmit_buffer(struct lpuart_port *sport)
 719{
 720	struct uart_port *port = &sport->port;
 721	u8 ch;
 722
 723	uart_port_tx(port, ch,
 724		readb(port->membase + UARTTCFIFO) < sport->txfifo_size,
 725		writeb(ch, port->membase + UARTDR));
 726}
 727
 728static inline void lpuart32_transmit_buffer(struct lpuart_port *sport)
 729{
 730	struct circ_buf *xmit = &sport->port.state->xmit;
 731	unsigned long txcnt;
 732
 733	if (sport->port.x_char) {
 734		lpuart32_write(&sport->port, sport->port.x_char, UARTDATA);
 735		sport->port.icount.tx++;
 736		sport->port.x_char = 0;
 737		return;
 738	}
 739
 740	if (lpuart_stopped_or_empty(&sport->port)) {
 741		lpuart32_stop_tx(&sport->port);
 742		return;
 743	}
 744
 745	txcnt = lpuart32_read(&sport->port, UARTWATER);
 746	txcnt = txcnt >> UARTWATER_TXCNT_OFF;
 747	txcnt &= UARTWATER_COUNT_MASK;
 748	while (!uart_circ_empty(xmit) && (txcnt < sport->txfifo_size)) {
 749		lpuart32_write(&sport->port, xmit->buf[xmit->tail], UARTDATA);
 750		uart_xmit_advance(&sport->port, 1);
 751		txcnt = lpuart32_read(&sport->port, UARTWATER);
 752		txcnt = txcnt >> UARTWATER_TXCNT_OFF;
 753		txcnt &= UARTWATER_COUNT_MASK;
 754	}
 755
 756	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
 757		uart_write_wakeup(&sport->port);
 758
 759	if (uart_circ_empty(xmit))
 760		lpuart32_stop_tx(&sport->port);
 761}
 762
 763static void lpuart_start_tx(struct uart_port *port)
 764{
 765	struct lpuart_port *sport = container_of(port,
 766			struct lpuart_port, port);
 767	unsigned char temp;
 768
 769	temp = readb(port->membase + UARTCR2);
 770	writeb(temp | UARTCR2_TIE, port->membase + UARTCR2);
 771
 772	if (sport->lpuart_dma_tx_use) {
 773		if (!lpuart_stopped_or_empty(port))
 774			lpuart_dma_tx(sport);
 775	} else {
 776		if (readb(port->membase + UARTSR1) & UARTSR1_TDRE)
 777			lpuart_transmit_buffer(sport);
 778	}
 779}
 780
 781static void lpuart32_start_tx(struct uart_port *port)
 782{
 783	struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
 784	unsigned long temp;
 785
 786	if (sport->lpuart_dma_tx_use) {
 787		if (!lpuart_stopped_or_empty(port))
 788			lpuart_dma_tx(sport);
 789	} else {
 790		temp = lpuart32_read(port, UARTCTRL);
 791		lpuart32_write(port, temp | UARTCTRL_TIE, UARTCTRL);
 792
 793		if (lpuart32_read(port, UARTSTAT) & UARTSTAT_TDRE)
 794			lpuart32_transmit_buffer(sport);
 795	}
 796}
 797
 798static void
 799lpuart_uart_pm(struct uart_port *port, unsigned int state, unsigned int oldstate)
 800{
 801	switch (state) {
 802	case UART_PM_STATE_OFF:
 803		pm_runtime_mark_last_busy(port->dev);
 804		pm_runtime_put_autosuspend(port->dev);
 805		break;
 806	default:
 807		pm_runtime_get_sync(port->dev);
 808		break;
 809	}
 810}
 811
 812/* return TIOCSER_TEMT when transmitter is not busy */
 813static unsigned int lpuart_tx_empty(struct uart_port *port)
 814{
 815	struct lpuart_port *sport = container_of(port,
 816			struct lpuart_port, port);
 817	unsigned char sr1 = readb(port->membase + UARTSR1);
 818	unsigned char sfifo = readb(port->membase + UARTSFIFO);
 819
 820	if (sport->dma_tx_in_progress)
 821		return 0;
 822
 823	if (sr1 & UARTSR1_TC && sfifo & UARTSFIFO_TXEMPT)
 824		return TIOCSER_TEMT;
 825
 826	return 0;
 827}
 828
 829static unsigned int lpuart32_tx_empty(struct uart_port *port)
 830{
 831	struct lpuart_port *sport = container_of(port,
 832			struct lpuart_port, port);
 833	unsigned long stat = lpuart32_read(port, UARTSTAT);
 834	unsigned long sfifo = lpuart32_read(port, UARTFIFO);
 
 835
 836	if (sport->dma_tx_in_progress)
 837		return 0;
 838
 839	if (stat & UARTSTAT_TC && sfifo & UARTFIFO_TXEMPT)
 
 
 
 
 
 840		return TIOCSER_TEMT;
 841
 842	return 0;
 843}
 844
 845static void lpuart_txint(struct lpuart_port *sport)
 846{
 847	spin_lock(&sport->port.lock);
 848	lpuart_transmit_buffer(sport);
 849	spin_unlock(&sport->port.lock);
 850}
 851
 852static void lpuart_rxint(struct lpuart_port *sport)
 853{
 854	unsigned int flg, ignored = 0, overrun = 0;
 855	struct tty_port *port = &sport->port.state->port;
 856	unsigned char rx, sr;
 857
 858	spin_lock(&sport->port.lock);
 859
 860	while (!(readb(sport->port.membase + UARTSFIFO) & UARTSFIFO_RXEMPT)) {
 861		flg = TTY_NORMAL;
 862		sport->port.icount.rx++;
 863		/*
 864		 * to clear the FE, OR, NF, FE, PE flags,
 865		 * read SR1 then read DR
 866		 */
 867		sr = readb(sport->port.membase + UARTSR1);
 868		rx = readb(sport->port.membase + UARTDR);
 869
 870		if (uart_prepare_sysrq_char(&sport->port, rx))
 871			continue;
 872
 873		if (sr & (UARTSR1_PE | UARTSR1_OR | UARTSR1_FE)) {
 874			if (sr & UARTSR1_PE)
 875				sport->port.icount.parity++;
 876			else if (sr & UARTSR1_FE)
 877				sport->port.icount.frame++;
 878
 879			if (sr & UARTSR1_OR)
 880				overrun++;
 881
 882			if (sr & sport->port.ignore_status_mask) {
 883				if (++ignored > 100)
 884					goto out;
 885				continue;
 886			}
 887
 888			sr &= sport->port.read_status_mask;
 889
 890			if (sr & UARTSR1_PE)
 891				flg = TTY_PARITY;
 892			else if (sr & UARTSR1_FE)
 893				flg = TTY_FRAME;
 894
 895			if (sr & UARTSR1_OR)
 896				flg = TTY_OVERRUN;
 897
 898			sport->port.sysrq = 0;
 899		}
 900
 901		if (tty_insert_flip_char(port, rx, flg) == 0)
 902			sport->port.icount.buf_overrun++;
 903	}
 904
 905out:
 906	if (overrun) {
 907		sport->port.icount.overrun += overrun;
 908
 909		/*
 910		 * Overruns cause FIFO pointers to become missaligned.
 911		 * Flushing the receive FIFO reinitializes the pointers.
 912		 */
 913		writeb(UARTCFIFO_RXFLUSH, sport->port.membase + UARTCFIFO);
 914		writeb(UARTSFIFO_RXOF, sport->port.membase + UARTSFIFO);
 915	}
 916
 917	uart_unlock_and_check_sysrq(&sport->port);
 918
 919	tty_flip_buffer_push(port);
 920}
 921
 922static void lpuart32_txint(struct lpuart_port *sport)
 923{
 924	spin_lock(&sport->port.lock);
 925	lpuart32_transmit_buffer(sport);
 926	spin_unlock(&sport->port.lock);
 927}
 928
 929static void lpuart32_rxint(struct lpuart_port *sport)
 930{
 931	unsigned int flg, ignored = 0;
 932	struct tty_port *port = &sport->port.state->port;
 933	unsigned long rx, sr;
 934	bool is_break;
 935
 936	spin_lock(&sport->port.lock);
 937
 938	while (!(lpuart32_read(&sport->port, UARTFIFO) & UARTFIFO_RXEMPT)) {
 939		flg = TTY_NORMAL;
 940		sport->port.icount.rx++;
 941		/*
 942		 * to clear the FE, OR, NF, FE, PE flags,
 943		 * read STAT then read DATA reg
 944		 */
 945		sr = lpuart32_read(&sport->port, UARTSTAT);
 946		rx = lpuart32_read(&sport->port, UARTDATA);
 947		rx &= UARTDATA_MASK;
 948
 949		/*
 950		 * The LPUART can't distinguish between a break and a framing error,
 951		 * thus we assume it is a break if the received data is zero.
 952		 */
 953		is_break = (sr & UARTSTAT_FE) && !rx;
 954
 955		if (is_break && uart_handle_break(&sport->port))
 956			continue;
 957
 958		if (uart_prepare_sysrq_char(&sport->port, rx))
 959			continue;
 960
 961		if (sr & (UARTSTAT_PE | UARTSTAT_OR | UARTSTAT_FE)) {
 962			if (sr & UARTSTAT_PE) {
 963				sport->port.icount.parity++;
 964			} else if (sr & UARTSTAT_FE) {
 965				if (is_break)
 966					sport->port.icount.brk++;
 967				else
 968					sport->port.icount.frame++;
 969			}
 970
 971			if (sr & UARTSTAT_OR)
 972				sport->port.icount.overrun++;
 973
 974			if (sr & sport->port.ignore_status_mask) {
 975				if (++ignored > 100)
 976					goto out;
 977				continue;
 978			}
 979
 980			sr &= sport->port.read_status_mask;
 981
 982			if (sr & UARTSTAT_PE) {
 983				flg = TTY_PARITY;
 984			} else if (sr & UARTSTAT_FE) {
 985				if (is_break)
 986					flg = TTY_BREAK;
 987				else
 988					flg = TTY_FRAME;
 989			}
 990
 991			if (sr & UARTSTAT_OR)
 992				flg = TTY_OVERRUN;
 993		}
 994
 995		if (sport->is_cs7)
 996			rx &= 0x7F;
 997
 998		if (tty_insert_flip_char(port, rx, flg) == 0)
 999			sport->port.icount.buf_overrun++;
1000	}
1001
1002out:
1003	uart_unlock_and_check_sysrq(&sport->port);
1004
1005	tty_flip_buffer_push(port);
1006}
1007
1008static irqreturn_t lpuart_int(int irq, void *dev_id)
1009{
1010	struct lpuart_port *sport = dev_id;
1011	unsigned char sts;
1012
1013	sts = readb(sport->port.membase + UARTSR1);
1014
1015	/* SysRq, using dma, check for linebreak by framing err. */
1016	if (sts & UARTSR1_FE && sport->lpuart_dma_rx_use) {
1017		readb(sport->port.membase + UARTDR);
1018		uart_handle_break(&sport->port);
1019		/* linebreak produces some garbage, removing it */
1020		writeb(UARTCFIFO_RXFLUSH, sport->port.membase + UARTCFIFO);
1021		return IRQ_HANDLED;
1022	}
1023
1024	if (sts & UARTSR1_RDRF && !sport->lpuart_dma_rx_use)
1025		lpuart_rxint(sport);
1026
1027	if (sts & UARTSR1_TDRE && !sport->lpuart_dma_tx_use)
1028		lpuart_txint(sport);
1029
1030	return IRQ_HANDLED;
1031}
1032
1033static irqreturn_t lpuart32_int(int irq, void *dev_id)
1034{
1035	struct lpuart_port *sport = dev_id;
1036	unsigned long sts, rxcount;
1037
1038	sts = lpuart32_read(&sport->port, UARTSTAT);
1039	rxcount = lpuart32_read(&sport->port, UARTWATER);
1040	rxcount = rxcount >> UARTWATER_RXCNT_OFF;
1041
1042	if ((sts & UARTSTAT_RDRF || rxcount > 0) && !sport->lpuart_dma_rx_use)
1043		lpuart32_rxint(sport);
1044
1045	if ((sts & UARTSTAT_TDRE) && !sport->lpuart_dma_tx_use)
1046		lpuart32_txint(sport);
1047
1048	lpuart32_write(&sport->port, sts, UARTSTAT);
1049	return IRQ_HANDLED;
1050}
1051
1052
1053static inline void lpuart_handle_sysrq_chars(struct uart_port *port,
1054					     unsigned char *p, int count)
1055{
1056	while (count--) {
1057		if (*p && uart_handle_sysrq_char(port, *p))
1058			return;
1059		p++;
1060	}
1061}
1062
1063static void lpuart_handle_sysrq(struct lpuart_port *sport)
1064{
1065	struct circ_buf *ring = &sport->rx_ring;
1066	int count;
1067
1068	if (ring->head < ring->tail) {
1069		count = sport->rx_sgl.length - ring->tail;
1070		lpuart_handle_sysrq_chars(&sport->port,
1071					  ring->buf + ring->tail, count);
1072		ring->tail = 0;
1073	}
1074
1075	if (ring->head > ring->tail) {
1076		count = ring->head - ring->tail;
1077		lpuart_handle_sysrq_chars(&sport->port,
1078					  ring->buf + ring->tail, count);
1079		ring->tail = ring->head;
1080	}
1081}
1082
1083static int lpuart_tty_insert_flip_string(struct tty_port *port,
1084	unsigned char *chars, size_t size, bool is_cs7)
1085{
1086	int i;
1087
1088	if (is_cs7)
1089		for (i = 0; i < size; i++)
1090			chars[i] &= 0x7F;
1091	return tty_insert_flip_string(port, chars, size);
1092}
1093
1094static void lpuart_copy_rx_to_tty(struct lpuart_port *sport)
1095{
1096	struct tty_port *port = &sport->port.state->port;
1097	struct dma_tx_state state;
1098	enum dma_status dmastat;
1099	struct dma_chan *chan = sport->dma_rx_chan;
1100	struct circ_buf *ring = &sport->rx_ring;
1101	unsigned long flags;
1102	int count, copied;
1103
1104	if (lpuart_is_32(sport)) {
1105		unsigned long sr = lpuart32_read(&sport->port, UARTSTAT);
1106
1107		if (sr & (UARTSTAT_PE | UARTSTAT_FE)) {
1108			/* Read DR to clear the error flags */
1109			lpuart32_read(&sport->port, UARTDATA);
1110
1111			if (sr & UARTSTAT_PE)
1112				sport->port.icount.parity++;
1113			else if (sr & UARTSTAT_FE)
1114				sport->port.icount.frame++;
1115		}
1116	} else {
1117		unsigned char sr = readb(sport->port.membase + UARTSR1);
1118
1119		if (sr & (UARTSR1_PE | UARTSR1_FE)) {
1120			unsigned char cr2;
1121
1122			/* Disable receiver during this operation... */
1123			cr2 = readb(sport->port.membase + UARTCR2);
1124			cr2 &= ~UARTCR2_RE;
1125			writeb(cr2, sport->port.membase + UARTCR2);
1126
1127			/* Read DR to clear the error flags */
1128			readb(sport->port.membase + UARTDR);
1129
1130			if (sr & UARTSR1_PE)
1131				sport->port.icount.parity++;
1132			else if (sr & UARTSR1_FE)
1133				sport->port.icount.frame++;
1134			/*
1135			 * At this point parity/framing error is
1136			 * cleared However, since the DMA already read
1137			 * the data register and we had to read it
1138			 * again after reading the status register to
1139			 * properly clear the flags, the FIFO actually
1140			 * underflowed... This requires a clearing of
1141			 * the FIFO...
1142			 */
1143			if (readb(sport->port.membase + UARTSFIFO) &
1144			    UARTSFIFO_RXUF) {
1145				writeb(UARTSFIFO_RXUF,
1146				       sport->port.membase + UARTSFIFO);
1147				writeb(UARTCFIFO_RXFLUSH,
1148				       sport->port.membase + UARTCFIFO);
1149			}
1150
1151			cr2 |= UARTCR2_RE;
1152			writeb(cr2, sport->port.membase + UARTCR2);
1153		}
1154	}
1155
1156	async_tx_ack(sport->dma_rx_desc);
1157
1158	spin_lock_irqsave(&sport->port.lock, flags);
1159
1160	dmastat = dmaengine_tx_status(chan, sport->dma_rx_cookie, &state);
1161	if (dmastat == DMA_ERROR) {
1162		dev_err(sport->port.dev, "Rx DMA transfer failed!\n");
1163		spin_unlock_irqrestore(&sport->port.lock, flags);
1164		return;
1165	}
1166
1167	/* CPU claims ownership of RX DMA buffer */
1168	dma_sync_sg_for_cpu(chan->device->dev, &sport->rx_sgl, 1,
1169			    DMA_FROM_DEVICE);
1170
1171	/*
1172	 * ring->head points to the end of data already written by the DMA.
1173	 * ring->tail points to the beginning of data to be read by the
1174	 * framework.
1175	 * The current transfer size should not be larger than the dma buffer
1176	 * length.
1177	 */
1178	ring->head = sport->rx_sgl.length - state.residue;
1179	BUG_ON(ring->head > sport->rx_sgl.length);
1180
1181	/*
1182	 * Silent handling of keys pressed in the sysrq timeframe
1183	 */
1184	if (sport->port.sysrq) {
1185		lpuart_handle_sysrq(sport);
1186		goto exit;
1187	}
1188
1189	/*
1190	 * At this point ring->head may point to the first byte right after the
1191	 * last byte of the dma buffer:
1192	 * 0 <= ring->head <= sport->rx_sgl.length
1193	 *
1194	 * However ring->tail must always points inside the dma buffer:
1195	 * 0 <= ring->tail <= sport->rx_sgl.length - 1
1196	 *
1197	 * Since we use a ring buffer, we have to handle the case
1198	 * where head is lower than tail. In such a case, we first read from
1199	 * tail to the end of the buffer then reset tail.
1200	 */
1201	if (ring->head < ring->tail) {
1202		count = sport->rx_sgl.length - ring->tail;
1203
1204		copied = lpuart_tty_insert_flip_string(port, ring->buf + ring->tail,
1205					count, sport->is_cs7);
1206		if (copied != count)
1207			sport->port.icount.buf_overrun++;
1208		ring->tail = 0;
1209		sport->port.icount.rx += copied;
1210	}
1211
1212	/* Finally we read data from tail to head */
1213	if (ring->tail < ring->head) {
1214		count = ring->head - ring->tail;
1215		copied = lpuart_tty_insert_flip_string(port, ring->buf + ring->tail,
1216					count, sport->is_cs7);
1217		if (copied != count)
1218			sport->port.icount.buf_overrun++;
1219		/* Wrap ring->head if needed */
1220		if (ring->head >= sport->rx_sgl.length)
1221			ring->head = 0;
1222		ring->tail = ring->head;
1223		sport->port.icount.rx += copied;
1224	}
1225
 
 
1226exit:
1227	dma_sync_sg_for_device(chan->device->dev, &sport->rx_sgl, 1,
1228			       DMA_FROM_DEVICE);
1229
1230	spin_unlock_irqrestore(&sport->port.lock, flags);
1231
1232	tty_flip_buffer_push(port);
1233	mod_timer(&sport->lpuart_timer, jiffies + sport->dma_rx_timeout);
 
1234}
1235
1236static void lpuart_dma_rx_complete(void *arg)
1237{
1238	struct lpuart_port *sport = arg;
1239
1240	lpuart_copy_rx_to_tty(sport);
1241}
1242
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1243static void lpuart_timer_func(struct timer_list *t)
1244{
1245	struct lpuart_port *sport = from_timer(sport, t, lpuart_timer);
 
 
 
 
 
 
 
 
 
 
 
 
1246
1247	lpuart_copy_rx_to_tty(sport);
 
 
 
 
 
 
 
 
 
 
 
 
 
1248}
1249
1250static inline int lpuart_start_rx_dma(struct lpuart_port *sport)
1251{
1252	struct dma_slave_config dma_rx_sconfig = {};
1253	struct circ_buf *ring = &sport->rx_ring;
1254	int ret, nent;
1255	struct tty_port *port = &sport->port.state->port;
1256	struct tty_struct *tty = port->tty;
1257	struct ktermios *termios = &tty->termios;
1258	struct dma_chan *chan = sport->dma_rx_chan;
1259	unsigned int bits = tty_get_frame_size(termios->c_cflag);
1260	unsigned int baud = tty_get_baud_rate(tty);
1261
1262	/*
1263	 * Calculate length of one DMA buffer size to keep latency below
1264	 * 10ms at any baud rate.
1265	 */
1266	sport->rx_dma_rng_buf_len = (DMA_RX_TIMEOUT * baud /  bits / 1000) * 2;
1267	sport->rx_dma_rng_buf_len = (1 << (fls(sport->rx_dma_rng_buf_len) - 1));
 
 
 
 
 
 
 
1268	if (sport->rx_dma_rng_buf_len < 16)
1269		sport->rx_dma_rng_buf_len = 16;
1270
 
 
 
 
1271	ring->buf = kzalloc(sport->rx_dma_rng_buf_len, GFP_ATOMIC);
1272	if (!ring->buf)
1273		return -ENOMEM;
1274
1275	sg_init_one(&sport->rx_sgl, ring->buf, sport->rx_dma_rng_buf_len);
1276	nent = dma_map_sg(chan->device->dev, &sport->rx_sgl, 1,
1277			  DMA_FROM_DEVICE);
1278
1279	if (!nent) {
1280		dev_err(sport->port.dev, "DMA Rx mapping error\n");
1281		return -EINVAL;
1282	}
1283
1284	dma_rx_sconfig.src_addr = lpuart_dma_datareg_addr(sport);
1285	dma_rx_sconfig.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
1286	dma_rx_sconfig.src_maxburst = 1;
1287	dma_rx_sconfig.direction = DMA_DEV_TO_MEM;
1288	ret = dmaengine_slave_config(chan, &dma_rx_sconfig);
1289
1290	if (ret < 0) {
1291		dev_err(sport->port.dev,
1292				"DMA Rx slave config failed, err = %d\n", ret);
1293		return ret;
1294	}
1295
1296	sport->dma_rx_desc = dmaengine_prep_dma_cyclic(chan,
1297				 sg_dma_address(&sport->rx_sgl),
1298				 sport->rx_sgl.length,
1299				 sport->rx_sgl.length / 2,
1300				 DMA_DEV_TO_MEM,
1301				 DMA_PREP_INTERRUPT);
1302	if (!sport->dma_rx_desc) {
1303		dev_err(sport->port.dev, "Cannot prepare cyclic DMA\n");
1304		return -EFAULT;
1305	}
1306
1307	sport->dma_rx_desc->callback = lpuart_dma_rx_complete;
1308	sport->dma_rx_desc->callback_param = sport;
1309	sport->dma_rx_cookie = dmaengine_submit(sport->dma_rx_desc);
1310	dma_async_issue_pending(chan);
1311
1312	if (lpuart_is_32(sport)) {
1313		unsigned long temp = lpuart32_read(&sport->port, UARTBAUD);
1314
1315		lpuart32_write(&sport->port, temp | UARTBAUD_RDMAE, UARTBAUD);
 
 
 
 
 
 
1316	} else {
1317		writeb(readb(sport->port.membase + UARTCR5) | UARTCR5_RDMAS,
1318		       sport->port.membase + UARTCR5);
1319	}
1320
1321	return 0;
1322}
1323
1324static void lpuart_dma_rx_free(struct uart_port *port)
1325{
1326	struct lpuart_port *sport = container_of(port,
1327					struct lpuart_port, port);
1328	struct dma_chan *chan = sport->dma_rx_chan;
1329
1330	dmaengine_terminate_sync(chan);
 
 
 
1331	dma_unmap_sg(chan->device->dev, &sport->rx_sgl, 1, DMA_FROM_DEVICE);
1332	kfree(sport->rx_ring.buf);
1333	sport->rx_ring.tail = 0;
1334	sport->rx_ring.head = 0;
1335	sport->dma_rx_desc = NULL;
1336	sport->dma_rx_cookie = -EINVAL;
1337}
1338
1339static int lpuart_config_rs485(struct uart_port *port, struct ktermios *termios,
1340			struct serial_rs485 *rs485)
1341{
1342	struct lpuart_port *sport = container_of(port,
1343			struct lpuart_port, port);
1344
1345	u8 modem = readb(sport->port.membase + UARTMODEM) &
1346		~(UARTMODEM_TXRTSPOL | UARTMODEM_TXRTSE);
1347	writeb(modem, sport->port.membase + UARTMODEM);
1348
1349	if (rs485->flags & SER_RS485_ENABLED) {
1350		/* Enable auto RS-485 RTS mode */
1351		modem |= UARTMODEM_TXRTSE;
1352
1353		/*
1354		 * The hardware defaults to RTS logic HIGH while transfer.
1355		 * Switch polarity in case RTS shall be logic HIGH
1356		 * after transfer.
1357		 * Note: UART is assumed to be active high.
1358		 */
1359		if (rs485->flags & SER_RS485_RTS_ON_SEND)
1360			modem |= UARTMODEM_TXRTSPOL;
1361		else if (rs485->flags & SER_RS485_RTS_AFTER_SEND)
1362			modem &= ~UARTMODEM_TXRTSPOL;
1363	}
1364
1365	writeb(modem, sport->port.membase + UARTMODEM);
1366	return 0;
1367}
1368
1369static int lpuart32_config_rs485(struct uart_port *port, struct ktermios *termios,
1370			struct serial_rs485 *rs485)
1371{
1372	struct lpuart_port *sport = container_of(port,
1373			struct lpuart_port, port);
1374
1375	unsigned long modem = lpuart32_read(&sport->port, UARTMODIR)
1376				& ~(UARTMODEM_TXRTSPOL | UARTMODEM_TXRTSE);
1377	lpuart32_write(&sport->port, modem, UARTMODIR);
1378
1379	if (rs485->flags & SER_RS485_ENABLED) {
1380		/* Enable auto RS-485 RTS mode */
1381		modem |= UARTMODEM_TXRTSE;
1382
1383		/*
1384		 * The hardware defaults to RTS logic HIGH while transfer.
1385		 * Switch polarity in case RTS shall be logic HIGH
1386		 * after transfer.
1387		 * Note: UART is assumed to be active high.
1388		 */
1389		if (rs485->flags & SER_RS485_RTS_ON_SEND)
1390			modem &= ~UARTMODEM_TXRTSPOL;
1391		else if (rs485->flags & SER_RS485_RTS_AFTER_SEND)
1392			modem |= UARTMODEM_TXRTSPOL;
1393	}
1394
1395	lpuart32_write(&sport->port, modem, UARTMODIR);
1396	return 0;
1397}
1398
1399static unsigned int lpuart_get_mctrl(struct uart_port *port)
1400{
1401	unsigned int mctrl = 0;
1402	u8 reg;
1403
1404	reg = readb(port->membase + UARTCR1);
1405	if (reg & UARTCR1_LOOPS)
1406		mctrl |= TIOCM_LOOP;
1407
1408	return mctrl;
1409}
1410
1411static unsigned int lpuart32_get_mctrl(struct uart_port *port)
1412{
1413	unsigned int mctrl = TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
1414	u32 reg;
1415
1416	reg = lpuart32_read(port, UARTCTRL);
1417	if (reg & UARTCTRL_LOOPS)
1418		mctrl |= TIOCM_LOOP;
1419
1420	return mctrl;
1421}
1422
1423static void lpuart_set_mctrl(struct uart_port *port, unsigned int mctrl)
1424{
1425	u8 reg;
1426
1427	reg = readb(port->membase + UARTCR1);
1428
1429	/* for internal loopback we need LOOPS=1 and RSRC=0 */
1430	reg &= ~(UARTCR1_LOOPS | UARTCR1_RSRC);
1431	if (mctrl & TIOCM_LOOP)
1432		reg |= UARTCR1_LOOPS;
1433
1434	writeb(reg, port->membase + UARTCR1);
1435}
1436
1437static void lpuart32_set_mctrl(struct uart_port *port, unsigned int mctrl)
1438{
1439	u32 reg;
1440
1441	reg = lpuart32_read(port, UARTCTRL);
1442
1443	/* for internal loopback we need LOOPS=1 and RSRC=0 */
1444	reg &= ~(UARTCTRL_LOOPS | UARTCTRL_RSRC);
1445	if (mctrl & TIOCM_LOOP)
1446		reg |= UARTCTRL_LOOPS;
1447
1448	lpuart32_write(port, reg, UARTCTRL);
1449}
1450
1451static void lpuart_break_ctl(struct uart_port *port, int break_state)
1452{
1453	unsigned char temp;
1454
1455	temp = readb(port->membase + UARTCR2) & ~UARTCR2_SBK;
1456
1457	if (break_state != 0)
1458		temp |= UARTCR2_SBK;
1459
1460	writeb(temp, port->membase + UARTCR2);
1461}
1462
1463static void lpuart32_break_ctl(struct uart_port *port, int break_state)
1464{
1465	unsigned long temp;
1466
1467	temp = lpuart32_read(port, UARTCTRL) & ~UARTCTRL_SBK;
1468
1469	if (break_state != 0)
1470		temp |= UARTCTRL_SBK;
1471
1472	lpuart32_write(port, temp, UARTCTRL);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1473}
1474
1475static void lpuart_setup_watermark(struct lpuart_port *sport)
1476{
1477	unsigned char val, cr2;
1478	unsigned char cr2_saved;
1479
1480	cr2 = readb(sport->port.membase + UARTCR2);
1481	cr2_saved = cr2;
1482	cr2 &= ~(UARTCR2_TIE | UARTCR2_TCIE | UARTCR2_TE |
1483			UARTCR2_RIE | UARTCR2_RE);
1484	writeb(cr2, sport->port.membase + UARTCR2);
1485
1486	val = readb(sport->port.membase + UARTPFIFO);
1487	writeb(val | UARTPFIFO_TXFE | UARTPFIFO_RXFE,
1488			sport->port.membase + UARTPFIFO);
1489
1490	/* flush Tx and Rx FIFO */
1491	writeb(UARTCFIFO_TXFLUSH | UARTCFIFO_RXFLUSH,
1492			sport->port.membase + UARTCFIFO);
1493
1494	/* explicitly clear RDRF */
1495	if (readb(sport->port.membase + UARTSR1) & UARTSR1_RDRF) {
1496		readb(sport->port.membase + UARTDR);
1497		writeb(UARTSFIFO_RXUF, sport->port.membase + UARTSFIFO);
1498	}
1499
 
 
1500	writeb(0, sport->port.membase + UARTTWFIFO);
1501	writeb(1, sport->port.membase + UARTRWFIFO);
1502
1503	/* Restore cr2 */
1504	writeb(cr2_saved, sport->port.membase + UARTCR2);
1505}
1506
1507static void lpuart_setup_watermark_enable(struct lpuart_port *sport)
1508{
1509	unsigned char cr2;
1510
1511	lpuart_setup_watermark(sport);
1512
1513	cr2 = readb(sport->port.membase + UARTCR2);
1514	cr2 |= UARTCR2_RIE | UARTCR2_RE | UARTCR2_TE;
1515	writeb(cr2, sport->port.membase + UARTCR2);
1516}
1517
1518static void lpuart32_setup_watermark(struct lpuart_port *sport)
1519{
1520	unsigned long val, ctrl;
1521	unsigned long ctrl_saved;
1522
1523	ctrl = lpuart32_read(&sport->port, UARTCTRL);
1524	ctrl_saved = ctrl;
1525	ctrl &= ~(UARTCTRL_TIE | UARTCTRL_TCIE | UARTCTRL_TE |
1526			UARTCTRL_RIE | UARTCTRL_RE);
1527	lpuart32_write(&sport->port, ctrl, UARTCTRL);
1528
1529	/* enable FIFO mode */
1530	val = lpuart32_read(&sport->port, UARTFIFO);
1531	val |= UARTFIFO_TXFE | UARTFIFO_RXFE;
1532	val |= UARTFIFO_TXFLUSH | UARTFIFO_RXFLUSH;
 
1533	lpuart32_write(&sport->port, val, UARTFIFO);
1534
1535	/* set the watermark */
1536	val = (0x1 << UARTWATER_RXWATER_OFF) | (0x0 << UARTWATER_TXWATER_OFF);
 
 
 
1537	lpuart32_write(&sport->port, val, UARTWATER);
1538
 
 
 
 
 
 
 
1539	/* Restore cr2 */
1540	lpuart32_write(&sport->port, ctrl_saved, UARTCTRL);
1541}
1542
1543static void lpuart32_setup_watermark_enable(struct lpuart_port *sport)
1544{
1545	u32 temp;
1546
1547	lpuart32_setup_watermark(sport);
1548
1549	temp = lpuart32_read(&sport->port, UARTCTRL);
1550	temp |= UARTCTRL_RE | UARTCTRL_TE | UARTCTRL_ILIE;
 
1551	lpuart32_write(&sport->port, temp, UARTCTRL);
1552}
1553
1554static void rx_dma_timer_init(struct lpuart_port *sport)
1555{
 
 
 
1556	timer_setup(&sport->lpuart_timer, lpuart_timer_func, 0);
1557	sport->lpuart_timer.expires = jiffies + sport->dma_rx_timeout;
1558	add_timer(&sport->lpuart_timer);
1559}
1560
1561static void lpuart_request_dma(struct lpuart_port *sport)
1562{
1563	sport->dma_tx_chan = dma_request_chan(sport->port.dev, "tx");
1564	if (IS_ERR(sport->dma_tx_chan)) {
1565		dev_dbg_once(sport->port.dev,
1566			     "DMA tx channel request failed, operating without tx DMA (%ld)\n",
1567			     PTR_ERR(sport->dma_tx_chan));
1568		sport->dma_tx_chan = NULL;
1569	}
1570
1571	sport->dma_rx_chan = dma_request_chan(sport->port.dev, "rx");
1572	if (IS_ERR(sport->dma_rx_chan)) {
1573		dev_dbg_once(sport->port.dev,
1574			     "DMA rx channel request failed, operating without rx DMA (%ld)\n",
1575			     PTR_ERR(sport->dma_rx_chan));
1576		sport->dma_rx_chan = NULL;
1577	}
1578}
1579
1580static void lpuart_tx_dma_startup(struct lpuart_port *sport)
1581{
1582	u32 uartbaud;
1583	int ret;
1584
1585	if (uart_console(&sport->port))
1586		goto err;
1587
1588	if (!sport->dma_tx_chan)
1589		goto err;
1590
1591	ret = lpuart_dma_tx_request(&sport->port);
1592	if (ret)
1593		goto err;
1594
1595	init_waitqueue_head(&sport->dma_wait);
1596	sport->lpuart_dma_tx_use = true;
1597	if (lpuart_is_32(sport)) {
1598		uartbaud = lpuart32_read(&sport->port, UARTBAUD);
1599		lpuart32_write(&sport->port,
1600			       uartbaud | UARTBAUD_TDMAE, UARTBAUD);
1601	} else {
1602		writeb(readb(sport->port.membase + UARTCR5) |
1603		       UARTCR5_TDMAS, sport->port.membase + UARTCR5);
1604	}
1605
1606	return;
1607
1608err:
1609	sport->lpuart_dma_tx_use = false;
1610}
1611
1612static void lpuart_rx_dma_startup(struct lpuart_port *sport)
1613{
1614	int ret;
1615	unsigned char cr3;
1616
1617	if (uart_console(&sport->port))
1618		goto err;
1619
1620	if (!sport->dma_rx_chan)
1621		goto err;
1622
 
 
 
1623	ret = lpuart_start_rx_dma(sport);
1624	if (ret)
1625		goto err;
1626
1627	/* set Rx DMA timeout */
1628	sport->dma_rx_timeout = msecs_to_jiffies(DMA_RX_TIMEOUT);
1629	if (!sport->dma_rx_timeout)
1630		sport->dma_rx_timeout = 1;
1631
1632	sport->lpuart_dma_rx_use = true;
1633	rx_dma_timer_init(sport);
1634
1635	if (sport->port.has_sysrq && !lpuart_is_32(sport)) {
1636		cr3 = readb(sport->port.membase + UARTCR3);
1637		cr3 |= UARTCR3_FEIE;
1638		writeb(cr3, sport->port.membase + UARTCR3);
1639	}
1640
1641	return;
1642
1643err:
1644	sport->lpuart_dma_rx_use = false;
1645}
1646
1647static void lpuart_hw_setup(struct lpuart_port *sport)
1648{
1649	unsigned long flags;
1650
1651	spin_lock_irqsave(&sport->port.lock, flags);
1652
1653	lpuart_setup_watermark_enable(sport);
1654
1655	lpuart_rx_dma_startup(sport);
1656	lpuart_tx_dma_startup(sport);
1657
1658	spin_unlock_irqrestore(&sport->port.lock, flags);
1659}
1660
1661static int lpuart_startup(struct uart_port *port)
1662{
1663	struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
1664	unsigned char temp;
1665
1666	/* determine FIFO size and enable FIFO mode */
1667	temp = readb(sport->port.membase + UARTPFIFO);
1668
1669	sport->txfifo_size = UARTFIFO_DEPTH((temp >> UARTPFIFO_TXSIZE_OFF) &
1670					    UARTPFIFO_FIFOSIZE_MASK);
1671	sport->port.fifosize = sport->txfifo_size;
1672
1673	sport->rxfifo_size = UARTFIFO_DEPTH((temp >> UARTPFIFO_RXSIZE_OFF) &
1674					    UARTPFIFO_FIFOSIZE_MASK);
1675
1676	lpuart_request_dma(sport);
1677	lpuart_hw_setup(sport);
1678
1679	return 0;
1680}
1681
 
 
 
 
 
 
 
 
 
 
1682static void lpuart32_configure(struct lpuart_port *sport)
1683{
1684	unsigned long temp;
1685
1686	if (sport->lpuart_dma_rx_use) {
1687		/* RXWATER must be 0 */
1688		temp = lpuart32_read(&sport->port, UARTWATER);
1689		temp &= ~(UARTWATER_WATER_MASK << UARTWATER_RXWATER_OFF);
1690		lpuart32_write(&sport->port, temp, UARTWATER);
1691	}
1692	temp = lpuart32_read(&sport->port, UARTCTRL);
1693	if (!sport->lpuart_dma_rx_use)
1694		temp |= UARTCTRL_RIE;
1695	if (!sport->lpuart_dma_tx_use)
1696		temp |= UARTCTRL_TIE;
1697	lpuart32_write(&sport->port, temp, UARTCTRL);
1698}
1699
1700static void lpuart32_hw_setup(struct lpuart_port *sport)
1701{
1702	unsigned long flags;
1703
1704	spin_lock_irqsave(&sport->port.lock, flags);
1705
1706	lpuart32_setup_watermark_enable(sport);
1707
1708	lpuart_rx_dma_startup(sport);
1709	lpuart_tx_dma_startup(sport);
1710
 
1711	lpuart32_configure(sport);
1712
1713	spin_unlock_irqrestore(&sport->port.lock, flags);
1714}
1715
1716static int lpuart32_startup(struct uart_port *port)
1717{
1718	struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
1719	unsigned long temp;
1720
1721	/* determine FIFO size */
1722	temp = lpuart32_read(&sport->port, UARTFIFO);
1723
1724	sport->txfifo_size = UARTFIFO_DEPTH((temp >> UARTFIFO_TXSIZE_OFF) &
1725					    UARTFIFO_FIFOSIZE_MASK);
1726	sport->port.fifosize = sport->txfifo_size;
1727
1728	sport->rxfifo_size = UARTFIFO_DEPTH((temp >> UARTFIFO_RXSIZE_OFF) &
1729					    UARTFIFO_FIFOSIZE_MASK);
1730
1731	/*
1732	 * The LS1021A and LS1028A have a fixed FIFO depth of 16 words.
1733	 * Although they support the RX/TXSIZE fields, their encoding is
1734	 * different. Eg the reference manual states 0b101 is 16 words.
1735	 */
1736	if (is_layerscape_lpuart(sport)) {
1737		sport->rxfifo_size = 16;
1738		sport->txfifo_size = 16;
1739		sport->port.fifosize = sport->txfifo_size;
1740	}
1741
1742	lpuart_request_dma(sport);
1743	lpuart32_hw_setup(sport);
1744
1745	return 0;
1746}
1747
1748static void lpuart_dma_shutdown(struct lpuart_port *sport)
1749{
1750	if (sport->lpuart_dma_rx_use) {
1751		del_timer_sync(&sport->lpuart_timer);
1752		lpuart_dma_rx_free(&sport->port);
1753		sport->lpuart_dma_rx_use = false;
1754	}
1755
1756	if (sport->lpuart_dma_tx_use) {
1757		if (wait_event_interruptible_timeout(sport->dma_wait,
1758			!sport->dma_tx_in_progress, msecs_to_jiffies(300)) <= 0) {
1759			sport->dma_tx_in_progress = false;
1760			dmaengine_terminate_sync(sport->dma_tx_chan);
1761		}
1762		sport->lpuart_dma_tx_use = false;
1763	}
1764
1765	if (sport->dma_tx_chan)
1766		dma_release_channel(sport->dma_tx_chan);
1767	if (sport->dma_rx_chan)
1768		dma_release_channel(sport->dma_rx_chan);
1769}
1770
1771static void lpuart_shutdown(struct uart_port *port)
1772{
1773	struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
1774	unsigned char temp;
1775	unsigned long flags;
1776
1777	spin_lock_irqsave(&port->lock, flags);
1778
1779	/* disable Rx/Tx and interrupts */
1780	temp = readb(port->membase + UARTCR2);
1781	temp &= ~(UARTCR2_TE | UARTCR2_RE |
1782			UARTCR2_TIE | UARTCR2_TCIE | UARTCR2_RIE);
1783	writeb(temp, port->membase + UARTCR2);
1784
1785	spin_unlock_irqrestore(&port->lock, flags);
1786
1787	lpuart_dma_shutdown(sport);
1788}
1789
1790static void lpuart32_shutdown(struct uart_port *port)
1791{
1792	struct lpuart_port *sport =
1793		container_of(port, struct lpuart_port, port);
1794	unsigned long temp;
1795	unsigned long flags;
1796
1797	spin_lock_irqsave(&port->lock, flags);
1798
1799	/* disable Rx/Tx and interrupts */
 
 
 
 
 
 
 
 
 
1800	temp = lpuart32_read(port, UARTCTRL);
1801	temp &= ~(UARTCTRL_TE | UARTCTRL_RE |
1802			UARTCTRL_TIE | UARTCTRL_TCIE | UARTCTRL_RIE);
1803	lpuart32_write(port, temp, UARTCTRL);
1804
1805	spin_unlock_irqrestore(&port->lock, flags);
1806
1807	lpuart_dma_shutdown(sport);
1808}
1809
1810static void
1811lpuart_set_termios(struct uart_port *port, struct ktermios *termios,
1812		   const struct ktermios *old)
1813{
1814	struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
1815	unsigned long flags;
1816	unsigned char cr1, old_cr1, old_cr2, cr3, cr4, bdh, modem;
1817	unsigned int  baud;
1818	unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8;
1819	unsigned int sbr, brfa;
1820
1821	cr1 = old_cr1 = readb(sport->port.membase + UARTCR1);
1822	old_cr2 = readb(sport->port.membase + UARTCR2);
1823	cr3 = readb(sport->port.membase + UARTCR3);
1824	cr4 = readb(sport->port.membase + UARTCR4);
1825	bdh = readb(sport->port.membase + UARTBDH);
1826	modem = readb(sport->port.membase + UARTMODEM);
1827	/*
1828	 * only support CS8 and CS7, and for CS7 must enable PE.
1829	 * supported mode:
1830	 *  - (7,e/o,1)
1831	 *  - (8,n,1)
1832	 *  - (8,m/s,1)
1833	 *  - (8,e/o,1)
1834	 */
1835	while ((termios->c_cflag & CSIZE) != CS8 &&
1836		(termios->c_cflag & CSIZE) != CS7) {
1837		termios->c_cflag &= ~CSIZE;
1838		termios->c_cflag |= old_csize;
1839		old_csize = CS8;
1840	}
1841
1842	if ((termios->c_cflag & CSIZE) == CS8 ||
1843		(termios->c_cflag & CSIZE) == CS7)
1844		cr1 = old_cr1 & ~UARTCR1_M;
1845
1846	if (termios->c_cflag & CMSPAR) {
1847		if ((termios->c_cflag & CSIZE) != CS8) {
1848			termios->c_cflag &= ~CSIZE;
1849			termios->c_cflag |= CS8;
1850		}
1851		cr1 |= UARTCR1_M;
1852	}
1853
1854	/*
1855	 * When auto RS-485 RTS mode is enabled,
1856	 * hardware flow control need to be disabled.
1857	 */
1858	if (sport->port.rs485.flags & SER_RS485_ENABLED)
1859		termios->c_cflag &= ~CRTSCTS;
1860
1861	if (termios->c_cflag & CRTSCTS)
1862		modem |= UARTMODEM_RXRTSE | UARTMODEM_TXCTSE;
1863	else
1864		modem &= ~(UARTMODEM_RXRTSE | UARTMODEM_TXCTSE);
1865
1866	termios->c_cflag &= ~CSTOPB;
1867
1868	/* parity must be enabled when CS7 to match 8-bits format */
1869	if ((termios->c_cflag & CSIZE) == CS7)
1870		termios->c_cflag |= PARENB;
1871
1872	if (termios->c_cflag & PARENB) {
1873		if (termios->c_cflag & CMSPAR) {
1874			cr1 &= ~UARTCR1_PE;
1875			if (termios->c_cflag & PARODD)
1876				cr3 |= UARTCR3_T8;
1877			else
1878				cr3 &= ~UARTCR3_T8;
1879		} else {
1880			cr1 |= UARTCR1_PE;
1881			if ((termios->c_cflag & CSIZE) == CS8)
1882				cr1 |= UARTCR1_M;
1883			if (termios->c_cflag & PARODD)
1884				cr1 |= UARTCR1_PT;
1885			else
1886				cr1 &= ~UARTCR1_PT;
1887		}
1888	} else {
1889		cr1 &= ~UARTCR1_PE;
1890	}
1891
1892	/* ask the core to calculate the divisor */
1893	baud = uart_get_baud_rate(port, termios, old, 50, port->uartclk / 16);
1894
1895	/*
1896	 * Need to update the Ring buffer length according to the selected
1897	 * baud rate and restart Rx DMA path.
1898	 *
1899	 * Since timer function acqures sport->port.lock, need to stop before
1900	 * acquring same lock because otherwise del_timer_sync() can deadlock.
1901	 */
1902	if (old && sport->lpuart_dma_rx_use) {
1903		del_timer_sync(&sport->lpuart_timer);
1904		lpuart_dma_rx_free(&sport->port);
1905	}
1906
1907	spin_lock_irqsave(&sport->port.lock, flags);
1908
1909	sport->port.read_status_mask = 0;
1910	if (termios->c_iflag & INPCK)
1911		sport->port.read_status_mask |= UARTSR1_FE | UARTSR1_PE;
1912	if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
1913		sport->port.read_status_mask |= UARTSR1_FE;
1914
1915	/* characters to ignore */
1916	sport->port.ignore_status_mask = 0;
1917	if (termios->c_iflag & IGNPAR)
1918		sport->port.ignore_status_mask |= UARTSR1_PE;
1919	if (termios->c_iflag & IGNBRK) {
1920		sport->port.ignore_status_mask |= UARTSR1_FE;
1921		/*
1922		 * if we're ignoring parity and break indicators,
1923		 * ignore overruns too (for real raw support).
1924		 */
1925		if (termios->c_iflag & IGNPAR)
1926			sport->port.ignore_status_mask |= UARTSR1_OR;
1927	}
1928
1929	/* update the per-port timeout */
1930	uart_update_timeout(port, termios->c_cflag, baud);
1931
1932	/* wait transmit engin complete */
1933	lpuart_wait_bit_set(&sport->port, UARTSR1, UARTSR1_TC);
1934
1935	/* disable transmit and receive */
1936	writeb(old_cr2 & ~(UARTCR2_TE | UARTCR2_RE),
1937			sport->port.membase + UARTCR2);
1938
1939	sbr = sport->port.uartclk / (16 * baud);
1940	brfa = ((sport->port.uartclk - (16 * sbr * baud)) * 2) / baud;
1941	bdh &= ~UARTBDH_SBR_MASK;
1942	bdh |= (sbr >> 8) & 0x1F;
1943	cr4 &= ~UARTCR4_BRFA_MASK;
1944	brfa &= UARTCR4_BRFA_MASK;
1945	writeb(cr4 | brfa, sport->port.membase + UARTCR4);
1946	writeb(bdh, sport->port.membase + UARTBDH);
1947	writeb(sbr & 0xFF, sport->port.membase + UARTBDL);
1948	writeb(cr3, sport->port.membase + UARTCR3);
1949	writeb(cr1, sport->port.membase + UARTCR1);
1950	writeb(modem, sport->port.membase + UARTMODEM);
1951
1952	/* restore control register */
1953	writeb(old_cr2, sport->port.membase + UARTCR2);
1954
1955	if (old && sport->lpuart_dma_rx_use) {
1956		if (!lpuart_start_rx_dma(sport))
1957			rx_dma_timer_init(sport);
1958		else
1959			sport->lpuart_dma_rx_use = false;
1960	}
1961
1962	spin_unlock_irqrestore(&sport->port.lock, flags);
1963}
1964
1965static void __lpuart32_serial_setbrg(struct uart_port *port,
1966				     unsigned int baudrate, bool use_rx_dma,
1967				     bool use_tx_dma)
1968{
1969	u32 sbr, osr, baud_diff, tmp_osr, tmp_sbr, tmp_diff, tmp;
1970	u32 clk = port->uartclk;
1971
1972	/*
1973	 * The idea is to use the best OSR (over-sampling rate) possible.
1974	 * Note, OSR is typically hard-set to 16 in other LPUART instantiations.
1975	 * Loop to find the best OSR value possible, one that generates minimum
1976	 * baud_diff iterate through the rest of the supported values of OSR.
1977	 *
1978	 * Calculation Formula:
1979	 *  Baud Rate = baud clock / ((OSR+1) × SBR)
1980	 */
1981	baud_diff = baudrate;
1982	osr = 0;
1983	sbr = 0;
1984
1985	for (tmp_osr = 4; tmp_osr <= 32; tmp_osr++) {
1986		/* calculate the temporary sbr value  */
1987		tmp_sbr = (clk / (baudrate * tmp_osr));
1988		if (tmp_sbr == 0)
1989			tmp_sbr = 1;
1990
1991		/*
1992		 * calculate the baud rate difference based on the temporary
1993		 * osr and sbr values
1994		 */
1995		tmp_diff = clk / (tmp_osr * tmp_sbr) - baudrate;
1996
1997		/* select best values between sbr and sbr+1 */
1998		tmp = clk / (tmp_osr * (tmp_sbr + 1));
1999		if (tmp_diff > (baudrate - tmp)) {
2000			tmp_diff = baudrate - tmp;
2001			tmp_sbr++;
2002		}
2003
2004		if (tmp_sbr > UARTBAUD_SBR_MASK)
2005			continue;
2006
2007		if (tmp_diff <= baud_diff) {
2008			baud_diff = tmp_diff;
2009			osr = tmp_osr;
2010			sbr = tmp_sbr;
2011
2012			if (!baud_diff)
2013				break;
2014		}
2015	}
2016
2017	/* handle buadrate outside acceptable rate */
2018	if (baud_diff > ((baudrate / 100) * 3))
2019		dev_warn(port->dev,
2020			 "unacceptable baud rate difference of more than 3%%\n");
2021
2022	tmp = lpuart32_read(port, UARTBAUD);
2023
2024	if ((osr > 3) && (osr < 8))
2025		tmp |= UARTBAUD_BOTHEDGE;
2026
2027	tmp &= ~(UARTBAUD_OSR_MASK << UARTBAUD_OSR_SHIFT);
2028	tmp |= ((osr-1) & UARTBAUD_OSR_MASK) << UARTBAUD_OSR_SHIFT;
2029
2030	tmp &= ~UARTBAUD_SBR_MASK;
2031	tmp |= sbr & UARTBAUD_SBR_MASK;
2032
2033	if (!use_rx_dma)
2034		tmp &= ~UARTBAUD_RDMAE;
2035	if (!use_tx_dma)
2036		tmp &= ~UARTBAUD_TDMAE;
2037
2038	lpuart32_write(port, tmp, UARTBAUD);
2039}
2040
2041static void lpuart32_serial_setbrg(struct lpuart_port *sport,
2042				   unsigned int baudrate)
2043{
2044	__lpuart32_serial_setbrg(&sport->port, baudrate,
2045				 sport->lpuart_dma_rx_use,
2046				 sport->lpuart_dma_tx_use);
2047}
2048
2049
2050static void
2051lpuart32_set_termios(struct uart_port *port, struct ktermios *termios,
2052		     const struct ktermios *old)
2053{
2054	struct lpuart_port *sport = container_of(port, struct lpuart_port, port);
2055	unsigned long flags;
2056	unsigned long ctrl, old_ctrl, bd, modem;
2057	unsigned int  baud;
2058	unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8;
2059
2060	ctrl = old_ctrl = lpuart32_read(&sport->port, UARTCTRL);
2061	bd = lpuart32_read(&sport->port, UARTBAUD);
2062	modem = lpuart32_read(&sport->port, UARTMODIR);
2063	sport->is_cs7 = false;
2064	/*
2065	 * only support CS8 and CS7, and for CS7 must enable PE.
2066	 * supported mode:
2067	 *  - (7,e/o,1)
2068	 *  - (8,n,1)
2069	 *  - (8,m/s,1)
2070	 *  - (8,e/o,1)
2071	 */
2072	while ((termios->c_cflag & CSIZE) != CS8 &&
2073		(termios->c_cflag & CSIZE) != CS7) {
2074		termios->c_cflag &= ~CSIZE;
2075		termios->c_cflag |= old_csize;
2076		old_csize = CS8;
2077	}
2078
2079	if ((termios->c_cflag & CSIZE) == CS8 ||
2080		(termios->c_cflag & CSIZE) == CS7)
2081		ctrl = old_ctrl & ~UARTCTRL_M;
2082
2083	if (termios->c_cflag & CMSPAR) {
2084		if ((termios->c_cflag & CSIZE) != CS8) {
2085			termios->c_cflag &= ~CSIZE;
2086			termios->c_cflag |= CS8;
2087		}
2088		ctrl |= UARTCTRL_M;
2089	}
2090
2091	/*
2092	 * When auto RS-485 RTS mode is enabled,
2093	 * hardware flow control need to be disabled.
2094	 */
2095	if (sport->port.rs485.flags & SER_RS485_ENABLED)
2096		termios->c_cflag &= ~CRTSCTS;
2097
2098	if (termios->c_cflag & CRTSCTS)
2099		modem |= UARTMODIR_RXRTSE | UARTMODIR_TXCTSE;
2100	else
2101		modem &= ~(UARTMODIR_RXRTSE | UARTMODIR_TXCTSE);
2102
2103	if (termios->c_cflag & CSTOPB)
2104		bd |= UARTBAUD_SBNS;
2105	else
2106		bd &= ~UARTBAUD_SBNS;
2107
2108	/* parity must be enabled when CS7 to match 8-bits format */
2109	if ((termios->c_cflag & CSIZE) == CS7)
2110		termios->c_cflag |= PARENB;
2111
2112	if ((termios->c_cflag & PARENB)) {
2113		if (termios->c_cflag & CMSPAR) {
2114			ctrl &= ~UARTCTRL_PE;
2115			ctrl |= UARTCTRL_M;
2116		} else {
2117			ctrl |= UARTCTRL_PE;
2118			if ((termios->c_cflag & CSIZE) == CS8)
2119				ctrl |= UARTCTRL_M;
2120			if (termios->c_cflag & PARODD)
2121				ctrl |= UARTCTRL_PT;
2122			else
2123				ctrl &= ~UARTCTRL_PT;
2124		}
2125	} else {
2126		ctrl &= ~UARTCTRL_PE;
2127	}
2128
2129	/* ask the core to calculate the divisor */
2130	baud = uart_get_baud_rate(port, termios, old, 50, port->uartclk / 4);
2131
2132	/*
2133	 * Need to update the Ring buffer length according to the selected
2134	 * baud rate and restart Rx DMA path.
2135	 *
2136	 * Since timer function acqures sport->port.lock, need to stop before
2137	 * acquring same lock because otherwise del_timer_sync() can deadlock.
2138	 */
2139	if (old && sport->lpuart_dma_rx_use) {
2140		del_timer_sync(&sport->lpuart_timer);
2141		lpuart_dma_rx_free(&sport->port);
2142	}
2143
2144	spin_lock_irqsave(&sport->port.lock, flags);
2145
2146	sport->port.read_status_mask = 0;
2147	if (termios->c_iflag & INPCK)
2148		sport->port.read_status_mask |= UARTSTAT_FE | UARTSTAT_PE;
2149	if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
2150		sport->port.read_status_mask |= UARTSTAT_FE;
2151
2152	/* characters to ignore */
2153	sport->port.ignore_status_mask = 0;
2154	if (termios->c_iflag & IGNPAR)
2155		sport->port.ignore_status_mask |= UARTSTAT_PE;
2156	if (termios->c_iflag & IGNBRK) {
2157		sport->port.ignore_status_mask |= UARTSTAT_FE;
2158		/*
2159		 * if we're ignoring parity and break indicators,
2160		 * ignore overruns too (for real raw support).
2161		 */
2162		if (termios->c_iflag & IGNPAR)
2163			sport->port.ignore_status_mask |= UARTSTAT_OR;
2164	}
2165
2166	/* update the per-port timeout */
2167	uart_update_timeout(port, termios->c_cflag, baud);
2168
2169	/* wait transmit engin complete */
2170	lpuart32_write(&sport->port, 0, UARTMODIR);
2171	lpuart32_wait_bit_set(&sport->port, UARTSTAT, UARTSTAT_TC);
 
 
 
 
 
 
2172
2173	/* disable transmit and receive */
2174	lpuart32_write(&sport->port, old_ctrl & ~(UARTCTRL_TE | UARTCTRL_RE),
2175		       UARTCTRL);
2176
2177	lpuart32_write(&sport->port, bd, UARTBAUD);
2178	lpuart32_serial_setbrg(sport, baud);
 
 
 
 
 
2179	lpuart32_write(&sport->port, modem, UARTMODIR);
2180	lpuart32_write(&sport->port, ctrl, UARTCTRL);
2181	/* restore control register */
2182
2183	if ((ctrl & (UARTCTRL_PE | UARTCTRL_M)) == UARTCTRL_PE)
2184		sport->is_cs7 = true;
2185
2186	if (old && sport->lpuart_dma_rx_use) {
2187		if (!lpuart_start_rx_dma(sport))
2188			rx_dma_timer_init(sport);
2189		else
2190			sport->lpuart_dma_rx_use = false;
2191	}
2192
2193	spin_unlock_irqrestore(&sport->port.lock, flags);
2194}
2195
2196static const char *lpuart_type(struct uart_port *port)
2197{
2198	return "FSL_LPUART";
2199}
2200
2201static void lpuart_release_port(struct uart_port *port)
2202{
2203	/* nothing to do */
2204}
2205
2206static int lpuart_request_port(struct uart_port *port)
2207{
2208	return  0;
2209}
2210
2211/* configure/autoconfigure the port */
2212static void lpuart_config_port(struct uart_port *port, int flags)
2213{
2214	if (flags & UART_CONFIG_TYPE)
2215		port->type = PORT_LPUART;
2216}
2217
2218static int lpuart_verify_port(struct uart_port *port, struct serial_struct *ser)
2219{
2220	int ret = 0;
2221
2222	if (ser->type != PORT_UNKNOWN && ser->type != PORT_LPUART)
2223		ret = -EINVAL;
2224	if (port->irq != ser->irq)
2225		ret = -EINVAL;
2226	if (ser->io_type != UPIO_MEM)
2227		ret = -EINVAL;
2228	if (port->uartclk / 16 != ser->baud_base)
2229		ret = -EINVAL;
2230	if (port->iobase != ser->port)
2231		ret = -EINVAL;
2232	if (ser->hub6 != 0)
2233		ret = -EINVAL;
2234	return ret;
2235}
2236
2237static const struct uart_ops lpuart_pops = {
2238	.tx_empty	= lpuart_tx_empty,
2239	.set_mctrl	= lpuart_set_mctrl,
2240	.get_mctrl	= lpuart_get_mctrl,
2241	.stop_tx	= lpuart_stop_tx,
2242	.start_tx	= lpuart_start_tx,
2243	.stop_rx	= lpuart_stop_rx,
2244	.break_ctl	= lpuart_break_ctl,
2245	.startup	= lpuart_startup,
2246	.shutdown	= lpuart_shutdown,
2247	.set_termios	= lpuart_set_termios,
2248	.pm		= lpuart_uart_pm,
2249	.type		= lpuart_type,
2250	.request_port	= lpuart_request_port,
2251	.release_port	= lpuart_release_port,
2252	.config_port	= lpuart_config_port,
2253	.verify_port	= lpuart_verify_port,
2254	.flush_buffer	= lpuart_flush_buffer,
2255#if defined(CONFIG_CONSOLE_POLL)
2256	.poll_init	= lpuart_poll_init,
2257	.poll_get_char	= lpuart_poll_get_char,
2258	.poll_put_char	= lpuart_poll_put_char,
2259#endif
2260};
2261
2262static const struct uart_ops lpuart32_pops = {
2263	.tx_empty	= lpuart32_tx_empty,
2264	.set_mctrl	= lpuart32_set_mctrl,
2265	.get_mctrl	= lpuart32_get_mctrl,
2266	.stop_tx	= lpuart32_stop_tx,
2267	.start_tx	= lpuart32_start_tx,
2268	.stop_rx	= lpuart32_stop_rx,
2269	.break_ctl	= lpuart32_break_ctl,
2270	.startup	= lpuart32_startup,
2271	.shutdown	= lpuart32_shutdown,
2272	.set_termios	= lpuart32_set_termios,
2273	.pm		= lpuart_uart_pm,
2274	.type		= lpuart_type,
2275	.request_port	= lpuart_request_port,
2276	.release_port	= lpuart_release_port,
2277	.config_port	= lpuart_config_port,
2278	.verify_port	= lpuart_verify_port,
2279	.flush_buffer	= lpuart_flush_buffer,
2280#if defined(CONFIG_CONSOLE_POLL)
2281	.poll_init	= lpuart32_poll_init,
2282	.poll_get_char	= lpuart32_poll_get_char,
2283	.poll_put_char	= lpuart32_poll_put_char,
2284#endif
2285};
2286
2287static struct lpuart_port *lpuart_ports[UART_NR];
2288
2289#ifdef CONFIG_SERIAL_FSL_LPUART_CONSOLE
2290static void lpuart_console_putchar(struct uart_port *port, unsigned char ch)
2291{
2292	lpuart_wait_bit_set(port, UARTSR1, UARTSR1_TDRE);
2293	writeb(ch, port->membase + UARTDR);
2294}
2295
2296static void lpuart32_console_putchar(struct uart_port *port, unsigned char ch)
2297{
2298	lpuart32_wait_bit_set(port, UARTSTAT, UARTSTAT_TDRE);
2299	lpuart32_write(port, ch, UARTDATA);
2300}
2301
2302static void
2303lpuart_console_write(struct console *co, const char *s, unsigned int count)
2304{
2305	struct lpuart_port *sport = lpuart_ports[co->index];
2306	unsigned char  old_cr2, cr2;
2307	unsigned long flags;
2308	int locked = 1;
2309
2310	if (oops_in_progress)
2311		locked = spin_trylock_irqsave(&sport->port.lock, flags);
2312	else
2313		spin_lock_irqsave(&sport->port.lock, flags);
2314
2315	/* first save CR2 and then disable interrupts */
2316	cr2 = old_cr2 = readb(sport->port.membase + UARTCR2);
2317	cr2 |= UARTCR2_TE | UARTCR2_RE;
2318	cr2 &= ~(UARTCR2_TIE | UARTCR2_TCIE | UARTCR2_RIE);
2319	writeb(cr2, sport->port.membase + UARTCR2);
2320
2321	uart_console_write(&sport->port, s, count, lpuart_console_putchar);
2322
2323	/* wait for transmitter finish complete and restore CR2 */
2324	lpuart_wait_bit_set(&sport->port, UARTSR1, UARTSR1_TC);
2325
2326	writeb(old_cr2, sport->port.membase + UARTCR2);
2327
2328	if (locked)
2329		spin_unlock_irqrestore(&sport->port.lock, flags);
2330}
2331
2332static void
2333lpuart32_console_write(struct console *co, const char *s, unsigned int count)
2334{
2335	struct lpuart_port *sport = lpuart_ports[co->index];
2336	unsigned long  old_cr, cr;
2337	unsigned long flags;
2338	int locked = 1;
2339
2340	if (oops_in_progress)
2341		locked = spin_trylock_irqsave(&sport->port.lock, flags);
2342	else
2343		spin_lock_irqsave(&sport->port.lock, flags);
2344
2345	/* first save CR2 and then disable interrupts */
2346	cr = old_cr = lpuart32_read(&sport->port, UARTCTRL);
2347	cr |= UARTCTRL_TE | UARTCTRL_RE;
2348	cr &= ~(UARTCTRL_TIE | UARTCTRL_TCIE | UARTCTRL_RIE);
2349	lpuart32_write(&sport->port, cr, UARTCTRL);
2350
2351	uart_console_write(&sport->port, s, count, lpuart32_console_putchar);
2352
2353	/* wait for transmitter finish complete and restore CR2 */
2354	lpuart32_wait_bit_set(&sport->port, UARTSTAT, UARTSTAT_TC);
2355
2356	lpuart32_write(&sport->port, old_cr, UARTCTRL);
2357
2358	if (locked)
2359		spin_unlock_irqrestore(&sport->port.lock, flags);
2360}
2361
2362/*
2363 * if the port was already initialised (eg, by a boot loader),
2364 * try to determine the current setup.
2365 */
2366static void __init
2367lpuart_console_get_options(struct lpuart_port *sport, int *baud,
2368			   int *parity, int *bits)
2369{
2370	unsigned char cr, bdh, bdl, brfa;
2371	unsigned int sbr, uartclk, baud_raw;
2372
2373	cr = readb(sport->port.membase + UARTCR2);
2374	cr &= UARTCR2_TE | UARTCR2_RE;
2375	if (!cr)
2376		return;
2377
2378	/* ok, the port was enabled */
2379
2380	cr = readb(sport->port.membase + UARTCR1);
2381
2382	*parity = 'n';
2383	if (cr & UARTCR1_PE) {
2384		if (cr & UARTCR1_PT)
2385			*parity = 'o';
2386		else
2387			*parity = 'e';
2388	}
2389
2390	if (cr & UARTCR1_M)
2391		*bits = 9;
2392	else
2393		*bits = 8;
2394
2395	bdh = readb(sport->port.membase + UARTBDH);
2396	bdh &= UARTBDH_SBR_MASK;
2397	bdl = readb(sport->port.membase + UARTBDL);
2398	sbr = bdh;
2399	sbr <<= 8;
2400	sbr |= bdl;
2401	brfa = readb(sport->port.membase + UARTCR4);
2402	brfa &= UARTCR4_BRFA_MASK;
2403
2404	uartclk = lpuart_get_baud_clk_rate(sport);
2405	/*
2406	 * baud = mod_clk/(16*(sbr[13]+(brfa)/32)
2407	 */
2408	baud_raw = uartclk / (16 * (sbr + brfa / 32));
2409
2410	if (*baud != baud_raw)
2411		dev_info(sport->port.dev, "Serial: Console lpuart rounded baud rate"
2412				"from %d to %d\n", baud_raw, *baud);
2413}
2414
2415static void __init
2416lpuart32_console_get_options(struct lpuart_port *sport, int *baud,
2417			   int *parity, int *bits)
2418{
2419	unsigned long cr, bd;
2420	unsigned int sbr, uartclk, baud_raw;
2421
2422	cr = lpuart32_read(&sport->port, UARTCTRL);
2423	cr &= UARTCTRL_TE | UARTCTRL_RE;
2424	if (!cr)
2425		return;
2426
2427	/* ok, the port was enabled */
2428
2429	cr = lpuart32_read(&sport->port, UARTCTRL);
2430
2431	*parity = 'n';
2432	if (cr & UARTCTRL_PE) {
2433		if (cr & UARTCTRL_PT)
2434			*parity = 'o';
2435		else
2436			*parity = 'e';
2437	}
2438
2439	if (cr & UARTCTRL_M)
2440		*bits = 9;
2441	else
2442		*bits = 8;
2443
2444	bd = lpuart32_read(&sport->port, UARTBAUD);
2445	bd &= UARTBAUD_SBR_MASK;
2446	if (!bd)
2447		return;
2448
2449	sbr = bd;
2450	uartclk = lpuart_get_baud_clk_rate(sport);
2451	/*
2452	 * baud = mod_clk/(16*(sbr[13]+(brfa)/32)
2453	 */
2454	baud_raw = uartclk / (16 * sbr);
2455
2456	if (*baud != baud_raw)
2457		dev_info(sport->port.dev, "Serial: Console lpuart rounded baud rate"
2458				"from %d to %d\n", baud_raw, *baud);
2459}
2460
2461static int __init lpuart_console_setup(struct console *co, char *options)
2462{
2463	struct lpuart_port *sport;
2464	int baud = 115200;
2465	int bits = 8;
2466	int parity = 'n';
2467	int flow = 'n';
2468
2469	/*
2470	 * check whether an invalid uart number has been specified, and
2471	 * if so, search for the first available port that does have
2472	 * console support.
2473	 */
2474	if (co->index == -1 || co->index >= ARRAY_SIZE(lpuart_ports))
2475		co->index = 0;
2476
2477	sport = lpuart_ports[co->index];
2478	if (sport == NULL)
2479		return -ENODEV;
2480
2481	if (options)
2482		uart_parse_options(options, &baud, &parity, &bits, &flow);
2483	else
2484		if (lpuart_is_32(sport))
2485			lpuart32_console_get_options(sport, &baud, &parity, &bits);
2486		else
2487			lpuart_console_get_options(sport, &baud, &parity, &bits);
2488
2489	if (lpuart_is_32(sport))
2490		lpuart32_setup_watermark(sport);
2491	else
2492		lpuart_setup_watermark(sport);
2493
2494	return uart_set_options(&sport->port, co, baud, parity, bits, flow);
2495}
2496
2497static struct uart_driver lpuart_reg;
2498static struct console lpuart_console = {
2499	.name		= DEV_NAME,
2500	.write		= lpuart_console_write,
2501	.device		= uart_console_device,
2502	.setup		= lpuart_console_setup,
2503	.flags		= CON_PRINTBUFFER,
2504	.index		= -1,
2505	.data		= &lpuart_reg,
2506};
2507
2508static struct console lpuart32_console = {
2509	.name		= DEV_NAME,
2510	.write		= lpuart32_console_write,
2511	.device		= uart_console_device,
2512	.setup		= lpuart_console_setup,
2513	.flags		= CON_PRINTBUFFER,
2514	.index		= -1,
2515	.data		= &lpuart_reg,
2516};
2517
2518static void lpuart_early_write(struct console *con, const char *s, unsigned n)
2519{
2520	struct earlycon_device *dev = con->data;
2521
2522	uart_console_write(&dev->port, s, n, lpuart_console_putchar);
2523}
2524
2525static void lpuart32_early_write(struct console *con, const char *s, unsigned n)
2526{
2527	struct earlycon_device *dev = con->data;
2528
2529	uart_console_write(&dev->port, s, n, lpuart32_console_putchar);
2530}
2531
2532static int __init lpuart_early_console_setup(struct earlycon_device *device,
2533					  const char *opt)
2534{
2535	if (!device->port.membase)
2536		return -ENODEV;
2537
2538	device->con->write = lpuart_early_write;
2539	return 0;
2540}
2541
2542static int __init lpuart32_early_console_setup(struct earlycon_device *device,
2543					  const char *opt)
2544{
2545	if (!device->port.membase)
2546		return -ENODEV;
2547
2548	if (device->port.iotype != UPIO_MEM32)
2549		device->port.iotype = UPIO_MEM32BE;
2550
2551	device->con->write = lpuart32_early_write;
2552	return 0;
2553}
2554
2555static int __init ls1028a_early_console_setup(struct earlycon_device *device,
2556					      const char *opt)
2557{
2558	u32 cr;
2559
2560	if (!device->port.membase)
2561		return -ENODEV;
2562
2563	device->port.iotype = UPIO_MEM32;
2564	device->con->write = lpuart32_early_write;
2565
2566	/* set the baudrate */
2567	if (device->port.uartclk && device->baud)
2568		__lpuart32_serial_setbrg(&device->port, device->baud,
2569					 false, false);
2570
2571	/* enable transmitter */
2572	cr = lpuart32_read(&device->port, UARTCTRL);
2573	cr |= UARTCTRL_TE;
2574	lpuart32_write(&device->port, cr, UARTCTRL);
2575
2576	return 0;
2577}
2578
2579static int __init lpuart32_imx_early_console_setup(struct earlycon_device *device,
2580						   const char *opt)
2581{
2582	if (!device->port.membase)
2583		return -ENODEV;
2584
2585	device->port.iotype = UPIO_MEM32;
2586	device->port.membase += IMX_REG_OFF;
2587	device->con->write = lpuart32_early_write;
2588
2589	return 0;
2590}
2591OF_EARLYCON_DECLARE(lpuart, "fsl,vf610-lpuart", lpuart_early_console_setup);
2592OF_EARLYCON_DECLARE(lpuart32, "fsl,ls1021a-lpuart", lpuart32_early_console_setup);
2593OF_EARLYCON_DECLARE(lpuart32, "fsl,ls1028a-lpuart", ls1028a_early_console_setup);
2594OF_EARLYCON_DECLARE(lpuart32, "fsl,imx7ulp-lpuart", lpuart32_imx_early_console_setup);
 
2595OF_EARLYCON_DECLARE(lpuart32, "fsl,imx8qxp-lpuart", lpuart32_imx_early_console_setup);
2596OF_EARLYCON_DECLARE(lpuart32, "fsl,imxrt1050-lpuart", lpuart32_imx_early_console_setup);
2597EARLYCON_DECLARE(lpuart, lpuart_early_console_setup);
2598EARLYCON_DECLARE(lpuart32, lpuart32_early_console_setup);
2599
2600#define LPUART_CONSOLE	(&lpuart_console)
2601#define LPUART32_CONSOLE	(&lpuart32_console)
2602#else
2603#define LPUART_CONSOLE	NULL
2604#define LPUART32_CONSOLE	NULL
2605#endif
2606
2607static struct uart_driver lpuart_reg = {
2608	.owner		= THIS_MODULE,
2609	.driver_name	= DRIVER_NAME,
2610	.dev_name	= DEV_NAME,
2611	.nr		= ARRAY_SIZE(lpuart_ports),
2612	.cons		= LPUART_CONSOLE,
2613};
2614
2615static const struct serial_rs485 lpuart_rs485_supported = {
2616	.flags = SER_RS485_ENABLED | SER_RS485_RTS_ON_SEND | SER_RS485_RTS_AFTER_SEND,
2617	/* delay_rts_* and RX_DURING_TX are not supported */
2618};
2619
2620static int lpuart_global_reset(struct lpuart_port *sport)
2621{
2622	struct uart_port *port = &sport->port;
2623	void __iomem *global_addr;
2624	unsigned long ctrl, bd;
2625	unsigned int val = 0;
2626	int ret;
2627
2628	ret = clk_prepare_enable(sport->ipg_clk);
2629	if (ret) {
2630		dev_err(sport->port.dev, "failed to enable uart ipg clk: %d\n", ret);
2631		return ret;
2632	}
2633
2634	if (is_imx7ulp_lpuart(sport) || is_imx8qxp_lpuart(sport)) {
2635		/*
2636		 * If the transmitter is used by earlycon, wait for transmit engine to
2637		 * complete and then reset.
2638		 */
2639		ctrl = lpuart32_read(port, UARTCTRL);
2640		if (ctrl & UARTCTRL_TE) {
2641			bd = lpuart32_read(&sport->port, UARTBAUD);
2642			if (read_poll_timeout(lpuart32_tx_empty, val, val, 1, 100000, false,
2643					      port)) {
2644				dev_warn(sport->port.dev,
2645					 "timeout waiting for transmit engine to complete\n");
2646				clk_disable_unprepare(sport->ipg_clk);
2647				return 0;
2648			}
2649		}
2650
2651		global_addr = port->membase + UART_GLOBAL - IMX_REG_OFF;
2652		writel(UART_GLOBAL_RST, global_addr);
2653		usleep_range(GLOBAL_RST_MIN_US, GLOBAL_RST_MAX_US);
2654		writel(0, global_addr);
2655		usleep_range(GLOBAL_RST_MIN_US, GLOBAL_RST_MAX_US);
2656
2657		/* Recover the transmitter for earlycon. */
2658		if (ctrl & UARTCTRL_TE) {
2659			lpuart32_write(port, bd, UARTBAUD);
2660			lpuart32_write(port, ctrl, UARTCTRL);
2661		}
2662	}
2663
2664	clk_disable_unprepare(sport->ipg_clk);
2665	return 0;
2666}
2667
2668static int lpuart_probe(struct platform_device *pdev)
2669{
2670	const struct lpuart_soc_data *sdata = of_device_get_match_data(&pdev->dev);
2671	struct device_node *np = pdev->dev.of_node;
2672	struct lpuart_port *sport;
2673	struct resource *res;
2674	irq_handler_t handler;
2675	int ret;
2676
2677	sport = devm_kzalloc(&pdev->dev, sizeof(*sport), GFP_KERNEL);
2678	if (!sport)
2679		return -ENOMEM;
2680
2681	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
2682	sport->port.membase = devm_ioremap_resource(&pdev->dev, res);
2683	if (IS_ERR(sport->port.membase))
2684		return PTR_ERR(sport->port.membase);
2685
2686	sport->port.membase += sdata->reg_off;
2687	sport->port.mapbase = res->start + sdata->reg_off;
2688	sport->port.dev = &pdev->dev;
2689	sport->port.type = PORT_LPUART;
2690	sport->devtype = sdata->devtype;
 
 
 
2691	ret = platform_get_irq(pdev, 0);
2692	if (ret < 0)
2693		return ret;
2694	sport->port.irq = ret;
2695	sport->port.iotype = sdata->iotype;
2696	if (lpuart_is_32(sport))
2697		sport->port.ops = &lpuart32_pops;
2698	else
2699		sport->port.ops = &lpuart_pops;
2700	sport->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_FSL_LPUART_CONSOLE);
2701	sport->port.flags = UPF_BOOT_AUTOCONF;
2702
2703	if (lpuart_is_32(sport))
2704		sport->port.rs485_config = lpuart32_config_rs485;
2705	else
2706		sport->port.rs485_config = lpuart_config_rs485;
2707	sport->port.rs485_supported = lpuart_rs485_supported;
2708
2709	sport->ipg_clk = devm_clk_get(&pdev->dev, "ipg");
2710	if (IS_ERR(sport->ipg_clk)) {
2711		ret = PTR_ERR(sport->ipg_clk);
2712		dev_err(&pdev->dev, "failed to get uart ipg clk: %d\n", ret);
2713		return ret;
2714	}
2715
2716	sport->baud_clk = NULL;
2717	if (is_imx8qxp_lpuart(sport)) {
2718		sport->baud_clk = devm_clk_get(&pdev->dev, "baud");
2719		if (IS_ERR(sport->baud_clk)) {
2720			ret = PTR_ERR(sport->baud_clk);
2721			dev_err(&pdev->dev, "failed to get uart baud clk: %d\n", ret);
2722			return ret;
2723		}
2724	}
2725
2726	ret = of_alias_get_id(np, "serial");
2727	if (ret < 0) {
2728		dev_err(&pdev->dev, "failed to get alias id, errno %d\n", ret);
2729		return ret;
2730	}
2731	if (ret >= ARRAY_SIZE(lpuart_ports)) {
2732		dev_err(&pdev->dev, "serial%d out of range\n", ret);
2733		return -EINVAL;
2734	}
2735	sport->port.line = ret;
2736
2737	ret = lpuart_enable_clks(sport);
2738	if (ret)
2739		return ret;
2740	sport->port.uartclk = lpuart_get_baud_clk_rate(sport);
2741
2742	lpuart_ports[sport->port.line] = sport;
2743
2744	platform_set_drvdata(pdev, &sport->port);
2745
2746	if (lpuart_is_32(sport)) {
2747		lpuart_reg.cons = LPUART32_CONSOLE;
2748		handler = lpuart32_int;
2749	} else {
2750		lpuart_reg.cons = LPUART_CONSOLE;
2751		handler = lpuart_int;
2752	}
2753
2754	pm_runtime_use_autosuspend(&pdev->dev);
2755	pm_runtime_set_autosuspend_delay(&pdev->dev, UART_AUTOSUSPEND_TIMEOUT);
2756	pm_runtime_set_active(&pdev->dev);
2757	pm_runtime_enable(&pdev->dev);
2758
2759	ret = lpuart_global_reset(sport);
2760	if (ret)
2761		goto failed_reset;
2762
2763	ret = uart_get_rs485_mode(&sport->port);
2764	if (ret)
2765		goto failed_get_rs485;
2766
2767	ret = uart_add_one_port(&lpuart_reg, &sport->port);
2768	if (ret)
2769		goto failed_attach_port;
2770
2771	ret = devm_request_irq(&pdev->dev, sport->port.irq, handler, 0,
2772				DRIVER_NAME, sport);
2773	if (ret)
2774		goto failed_irq_request;
2775
2776	return 0;
2777
2778failed_irq_request:
2779	uart_remove_one_port(&lpuart_reg, &sport->port);
2780failed_attach_port:
2781failed_get_rs485:
2782failed_reset:
2783	pm_runtime_disable(&pdev->dev);
2784	pm_runtime_set_suspended(&pdev->dev);
2785	pm_runtime_dont_use_autosuspend(&pdev->dev);
2786	lpuart_disable_clks(sport);
2787	return ret;
2788}
2789
2790static int lpuart_remove(struct platform_device *pdev)
2791{
2792	struct lpuart_port *sport = platform_get_drvdata(pdev);
2793
2794	uart_remove_one_port(&lpuart_reg, &sport->port);
2795
2796	lpuart_disable_clks(sport);
2797
2798	if (sport->dma_tx_chan)
2799		dma_release_channel(sport->dma_tx_chan);
2800
2801	if (sport->dma_rx_chan)
2802		dma_release_channel(sport->dma_rx_chan);
2803
2804	pm_runtime_disable(&pdev->dev);
2805	pm_runtime_set_suspended(&pdev->dev);
2806	pm_runtime_dont_use_autosuspend(&pdev->dev);
2807	return 0;
2808}
2809
2810static int lpuart_runtime_suspend(struct device *dev)
2811{
2812	struct platform_device *pdev = to_platform_device(dev);
2813	struct lpuart_port *sport = platform_get_drvdata(pdev);
2814
2815	lpuart_disable_clks(sport);
2816
2817	return 0;
2818};
2819
2820static int lpuart_runtime_resume(struct device *dev)
2821{
2822	struct platform_device *pdev = to_platform_device(dev);
2823	struct lpuart_port *sport = platform_get_drvdata(pdev);
2824
2825	return lpuart_enable_clks(sport);
2826};
2827
2828static void serial_lpuart_enable_wakeup(struct lpuart_port *sport, bool on)
2829{
2830	unsigned int val, baud;
2831
2832	if (lpuart_is_32(sport)) {
2833		val = lpuart32_read(&sport->port, UARTCTRL);
2834		baud = lpuart32_read(&sport->port, UARTBAUD);
2835		if (on) {
2836			/* set rx_watermark to 0 in wakeup source mode */
2837			lpuart32_write(&sport->port, 0, UARTWATER);
2838			val |= UARTCTRL_RIE;
2839			/* clear RXEDGIF flag before enable RXEDGIE interrupt */
2840			lpuart32_write(&sport->port, UARTSTAT_RXEDGIF, UARTSTAT);
2841			baud |= UARTBAUD_RXEDGIE;
2842		} else {
2843			val &= ~UARTCTRL_RIE;
2844			baud &= ~UARTBAUD_RXEDGIE;
2845		}
2846		lpuart32_write(&sport->port, val, UARTCTRL);
2847		lpuart32_write(&sport->port, baud, UARTBAUD);
2848	} else {
2849		val = readb(sport->port.membase + UARTCR2);
2850		if (on)
2851			val |= UARTCR2_RIE;
2852		else
2853			val &= ~UARTCR2_RIE;
2854		writeb(val, sport->port.membase + UARTCR2);
2855	}
2856}
2857
2858static bool lpuart_uport_is_active(struct lpuart_port *sport)
2859{
2860	struct tty_port *port = &sport->port.state->port;
2861	struct tty_struct *tty;
2862	struct device *tty_dev;
2863	int may_wake = 0;
2864
2865	tty = tty_port_tty_get(port);
2866	if (tty) {
2867		tty_dev = tty->dev;
2868		may_wake = device_may_wakeup(tty_dev);
2869		tty_kref_put(tty);
2870	}
2871
2872	if ((tty_port_initialized(port) && may_wake) ||
2873	    (!console_suspend_enabled && uart_console(&sport->port)))
2874		return true;
2875
2876	return false;
2877}
2878
2879static int lpuart_suspend_noirq(struct device *dev)
2880{
2881	struct lpuart_port *sport = dev_get_drvdata(dev);
2882	bool irq_wake = irqd_is_wakeup_set(irq_get_irq_data(sport->port.irq));
2883
2884	if (lpuart_uport_is_active(sport))
2885		serial_lpuart_enable_wakeup(sport, !!irq_wake);
2886
2887	pinctrl_pm_select_sleep_state(dev);
2888
2889	return 0;
2890}
2891
2892static int lpuart_resume_noirq(struct device *dev)
2893{
2894	struct lpuart_port *sport = dev_get_drvdata(dev);
2895	unsigned int val;
2896
2897	pinctrl_pm_select_default_state(dev);
2898
2899	if (lpuart_uport_is_active(sport)) {
2900		serial_lpuart_enable_wakeup(sport, false);
2901
2902		/* clear the wakeup flags */
2903		if (lpuart_is_32(sport)) {
2904			val = lpuart32_read(&sport->port, UARTSTAT);
2905			lpuart32_write(&sport->port, val, UARTSTAT);
2906		}
2907	}
2908
2909	return 0;
2910}
2911
2912static int lpuart_suspend(struct device *dev)
2913{
2914	struct lpuart_port *sport = dev_get_drvdata(dev);
2915	unsigned long temp, flags;
2916
2917	uart_suspend_port(&lpuart_reg, &sport->port);
2918
2919	if (lpuart_uport_is_active(sport)) {
2920		spin_lock_irqsave(&sport->port.lock, flags);
2921		if (lpuart_is_32(sport)) {
2922			/* disable Rx/Tx and interrupts */
2923			temp = lpuart32_read(&sport->port, UARTCTRL);
2924			temp &= ~(UARTCTRL_TE | UARTCTRL_TIE | UARTCTRL_TCIE);
2925			lpuart32_write(&sport->port, temp, UARTCTRL);
2926		} else {
2927			/* disable Rx/Tx and interrupts */
2928			temp = readb(sport->port.membase + UARTCR2);
2929			temp &= ~(UARTCR2_TE | UARTCR2_TIE | UARTCR2_TCIE);
2930			writeb(temp, sport->port.membase + UARTCR2);
2931		}
2932		spin_unlock_irqrestore(&sport->port.lock, flags);
2933
2934		if (sport->lpuart_dma_rx_use) {
2935			/*
2936			 * EDMA driver during suspend will forcefully release any
2937			 * non-idle DMA channels. If port wakeup is enabled or if port
2938			 * is console port or 'no_console_suspend' is set the Rx DMA
2939			 * cannot resume as expected, hence gracefully release the
2940			 * Rx DMA path before suspend and start Rx DMA path on resume.
2941			 */
2942			del_timer_sync(&sport->lpuart_timer);
2943			lpuart_dma_rx_free(&sport->port);
2944
2945			/* Disable Rx DMA to use UART port as wakeup source */
2946			spin_lock_irqsave(&sport->port.lock, flags);
2947			if (lpuart_is_32(sport)) {
2948				temp = lpuart32_read(&sport->port, UARTBAUD);
2949				lpuart32_write(&sport->port, temp & ~UARTBAUD_RDMAE,
2950					       UARTBAUD);
2951			} else {
2952				writeb(readb(sport->port.membase + UARTCR5) &
2953				       ~UARTCR5_RDMAS, sport->port.membase + UARTCR5);
2954			}
2955			spin_unlock_irqrestore(&sport->port.lock, flags);
2956		}
2957
2958		if (sport->lpuart_dma_tx_use) {
2959			spin_lock_irqsave(&sport->port.lock, flags);
2960			if (lpuart_is_32(sport)) {
2961				temp = lpuart32_read(&sport->port, UARTBAUD);
2962				temp &= ~UARTBAUD_TDMAE;
2963				lpuart32_write(&sport->port, temp, UARTBAUD);
2964			} else {
2965				temp = readb(sport->port.membase + UARTCR5);
2966				temp &= ~UARTCR5_TDMAS;
2967				writeb(temp, sport->port.membase + UARTCR5);
2968			}
2969			spin_unlock_irqrestore(&sport->port.lock, flags);
2970			sport->dma_tx_in_progress = false;
2971			dmaengine_terminate_sync(sport->dma_tx_chan);
2972		}
2973	} else if (pm_runtime_active(sport->port.dev)) {
2974		lpuart_disable_clks(sport);
2975		pm_runtime_disable(sport->port.dev);
2976		pm_runtime_set_suspended(sport->port.dev);
2977	}
2978
2979	return 0;
2980}
2981
2982static void lpuart_console_fixup(struct lpuart_port *sport)
2983{
2984	struct tty_port *port = &sport->port.state->port;
2985	struct uart_port *uport = &sport->port;
2986	struct ktermios termios;
2987
2988	/* i.MX7ULP enter VLLS mode that lpuart module power off and registers
2989	 * all lost no matter the port is wakeup source.
2990	 * For console port, console baud rate setting lost and print messy
2991	 * log when enable the console port as wakeup source. To avoid the
2992	 * issue happen, user should not enable uart port as wakeup source
2993	 * in VLLS mode, or restore console setting here.
2994	 */
2995	if (is_imx7ulp_lpuart(sport) && lpuart_uport_is_active(sport) &&
2996	    console_suspend_enabled && uart_console(&sport->port)) {
2997
2998		mutex_lock(&port->mutex);
2999		memset(&termios, 0, sizeof(struct ktermios));
3000		termios.c_cflag = uport->cons->cflag;
3001		if (port->tty && termios.c_cflag == 0)
3002			termios = port->tty->termios;
3003		uport->ops->set_termios(uport, &termios, NULL);
3004		mutex_unlock(&port->mutex);
3005	}
3006}
3007
3008static int lpuart_resume(struct device *dev)
3009{
3010	struct lpuart_port *sport = dev_get_drvdata(dev);
3011	int ret;
3012
3013	if (lpuart_uport_is_active(sport)) {
3014		if (lpuart_is_32(sport))
3015			lpuart32_hw_setup(sport);
3016		else
3017			lpuart_hw_setup(sport);
3018	} else if (pm_runtime_active(sport->port.dev)) {
3019		ret = lpuart_enable_clks(sport);
3020		if (ret)
3021			return ret;
3022		pm_runtime_set_active(sport->port.dev);
3023		pm_runtime_enable(sport->port.dev);
3024	}
3025
3026	lpuart_console_fixup(sport);
3027	uart_resume_port(&lpuart_reg, &sport->port);
3028
3029	return 0;
3030}
3031
3032static const struct dev_pm_ops lpuart_pm_ops = {
3033	RUNTIME_PM_OPS(lpuart_runtime_suspend,
3034			   lpuart_runtime_resume, NULL)
3035	NOIRQ_SYSTEM_SLEEP_PM_OPS(lpuart_suspend_noirq,
3036				      lpuart_resume_noirq)
3037	SYSTEM_SLEEP_PM_OPS(lpuart_suspend, lpuart_resume)
3038};
3039
3040static struct platform_driver lpuart_driver = {
3041	.probe		= lpuart_probe,
3042	.remove		= lpuart_remove,
3043	.driver		= {
3044		.name	= "fsl-lpuart",
3045		.of_match_table = lpuart_dt_ids,
3046		.pm	= pm_ptr(&lpuart_pm_ops),
3047	},
3048};
3049
3050static int __init lpuart_serial_init(void)
3051{
3052	int ret = uart_register_driver(&lpuart_reg);
3053
3054	if (ret)
3055		return ret;
3056
3057	ret = platform_driver_register(&lpuart_driver);
3058	if (ret)
3059		uart_unregister_driver(&lpuart_reg);
3060
3061	return ret;
3062}
3063
3064static void __exit lpuart_serial_exit(void)
3065{
3066	platform_driver_unregister(&lpuart_driver);
3067	uart_unregister_driver(&lpuart_reg);
3068}
3069
3070module_init(lpuart_serial_init);
3071module_exit(lpuart_serial_exit);
3072
3073MODULE_DESCRIPTION("Freescale lpuart serial port driver");
3074MODULE_LICENSE("GPL v2");