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v5.4
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * SuperH MSIOF SPI Controller Interface
   4 *
   5 * Copyright (c) 2009 Magnus Damm
   6 * Copyright (C) 2014 Renesas Electronics Corporation
   7 * Copyright (C) 2014-2017 Glider bvba
 
 
 
 
   8 */
   9
  10#include <linux/bitmap.h>
  11#include <linux/clk.h>
  12#include <linux/completion.h>
  13#include <linux/delay.h>
  14#include <linux/dma-mapping.h>
  15#include <linux/dmaengine.h>
  16#include <linux/err.h>
  17#include <linux/gpio.h>
  18#include <linux/gpio/consumer.h>
  19#include <linux/interrupt.h>
  20#include <linux/io.h>
  21#include <linux/iopoll.h>
  22#include <linux/kernel.h>
  23#include <linux/module.h>
  24#include <linux/of.h>
  25#include <linux/of_device.h>
  26#include <linux/platform_device.h>
  27#include <linux/pm_runtime.h>
  28#include <linux/sh_dma.h>
  29
  30#include <linux/spi/sh_msiof.h>
  31#include <linux/spi/spi.h>
  32
  33#include <asm/unaligned.h>
  34
 
  35struct sh_msiof_chipdata {
  36	u32 bits_per_word_mask;
  37	u16 tx_fifo_size;
  38	u16 rx_fifo_size;
  39	u16 ctlr_flags;
  40	u16 min_div_pow;
  41};
  42
  43struct sh_msiof_spi_priv {
  44	struct spi_controller *ctlr;
  45	void __iomem *mapbase;
  46	struct clk *clk;
  47	struct platform_device *pdev;
  48	struct sh_msiof_spi_info *info;
  49	struct completion done;
  50	struct completion done_txdma;
  51	unsigned int tx_fifo_size;
  52	unsigned int rx_fifo_size;
  53	unsigned int min_div_pow;
  54	void *tx_dma_page;
  55	void *rx_dma_page;
  56	dma_addr_t tx_dma_addr;
  57	dma_addr_t rx_dma_addr;
  58	unsigned short unused_ss;
  59	bool native_cs_inited;
  60	bool native_cs_high;
  61	bool slave_aborted;
  62};
  63
  64#define MAX_SS	3	/* Maximum number of native chip selects */
  65
  66#define TMDR1	0x00	/* Transmit Mode Register 1 */
  67#define TMDR2	0x04	/* Transmit Mode Register 2 */
  68#define TMDR3	0x08	/* Transmit Mode Register 3 */
  69#define RMDR1	0x10	/* Receive Mode Register 1 */
  70#define RMDR2	0x14	/* Receive Mode Register 2 */
  71#define RMDR3	0x18	/* Receive Mode Register 3 */
  72#define TSCR	0x20	/* Transmit Clock Select Register */
  73#define RSCR	0x22	/* Receive Clock Select Register (SH, A1, APE6) */
  74#define CTR	0x28	/* Control Register */
  75#define FCTR	0x30	/* FIFO Control Register */
  76#define STR	0x40	/* Status Register */
  77#define IER	0x44	/* Interrupt Enable Register */
  78#define TDR1	0x48	/* Transmit Control Data Register 1 (SH, A1) */
  79#define TDR2	0x4c	/* Transmit Control Data Register 2 (SH, A1) */
  80#define TFDR	0x50	/* Transmit FIFO Data Register */
  81#define RDR1	0x58	/* Receive Control Data Register 1 (SH, A1) */
  82#define RDR2	0x5c	/* Receive Control Data Register 2 (SH, A1) */
  83#define RFDR	0x60	/* Receive FIFO Data Register */
  84
  85/* TMDR1 and RMDR1 */
  86#define MDR1_TRMD	   BIT(31)  /* Transfer Mode (1 = Master mode) */
  87#define MDR1_SYNCMD_MASK   GENMASK(29, 28) /* SYNC Mode */
  88#define MDR1_SYNCMD_SPI	   (2 << 28)/*   Level mode/SPI */
  89#define MDR1_SYNCMD_LR	   (3 << 28)/*   L/R mode */
  90#define MDR1_SYNCAC_SHIFT  25       /* Sync Polarity (1 = Active-low) */
  91#define MDR1_BITLSB_SHIFT  24       /* MSB/LSB First (1 = LSB first) */
  92#define MDR1_DTDL_SHIFT	   20       /* Data Pin Bit Delay for MSIOF_SYNC */
  93#define MDR1_SYNCDL_SHIFT  16       /* Frame Sync Signal Timing Delay */
  94#define MDR1_FLD_MASK	   GENMASK(3, 2) /* Frame Sync Signal Interval (0-3) */
  95#define MDR1_FLD_SHIFT	   2
  96#define MDR1_XXSTP	   BIT(0)   /* Transmission/Reception Stop on FIFO */
  97/* TMDR1 */
  98#define TMDR1_PCON	   BIT(30)  /* Transfer Signal Connection */
  99#define TMDR1_SYNCCH_MASK  GENMASK(27, 26) /* Sync Signal Channel Select */
 100#define TMDR1_SYNCCH_SHIFT 26       /* 0=MSIOF_SYNC, 1=MSIOF_SS1, 2=MSIOF_SS2 */
 101
 102/* TMDR2 and RMDR2 */
 103#define MDR2_BITLEN1(i)	(((i) - 1) << 24) /* Data Size (8-32 bits) */
 104#define MDR2_WDLEN1(i)	(((i) - 1) << 16) /* Word Count (1-64/256 (SH, A1))) */
 105#define MDR2_GRPMASK1	BIT(0)      /* Group Output Mask 1 (SH, A1) */
 106
 107/* TSCR and RSCR */
 108#define SCR_BRPS_MASK	GENMASK(12, 8) /* Prescaler Setting (1-32) */
 109#define SCR_BRPS(i)	(((i) - 1) << 8)
 110#define SCR_BRDV_MASK	GENMASK(2, 0) /* Baud Rate Generator's Division Ratio */
 111#define SCR_BRDV_DIV_2	0
 112#define SCR_BRDV_DIV_4	1
 113#define SCR_BRDV_DIV_8	2
 114#define SCR_BRDV_DIV_16	3
 115#define SCR_BRDV_DIV_32	4
 116#define SCR_BRDV_DIV_1	7
 117
 118/* CTR */
 119#define CTR_TSCKIZ_MASK	GENMASK(31, 30) /* Transmit Clock I/O Polarity Select */
 120#define CTR_TSCKIZ_SCK	BIT(31)   /*   Disable SCK when TX disabled */
 121#define CTR_TSCKIZ_POL_SHIFT 30   /*   Transmit Clock Polarity */
 122#define CTR_RSCKIZ_MASK	GENMASK(29, 28) /* Receive Clock Polarity Select */
 123#define CTR_RSCKIZ_SCK	BIT(29)   /*   Must match CTR_TSCKIZ_SCK */
 124#define CTR_RSCKIZ_POL_SHIFT 28   /*   Receive Clock Polarity */
 125#define CTR_TEDG_SHIFT	     27   /* Transmit Timing (1 = falling edge) */
 126#define CTR_REDG_SHIFT	     26   /* Receive Timing (1 = falling edge) */
 127#define CTR_TXDIZ_MASK	GENMASK(23, 22) /* Pin Output When TX is Disabled */
 128#define CTR_TXDIZ_LOW	(0 << 22) /*   0 */
 129#define CTR_TXDIZ_HIGH	(1 << 22) /*   1 */
 130#define CTR_TXDIZ_HIZ	(2 << 22) /*   High-impedance */
 131#define CTR_TSCKE	BIT(15)   /* Transmit Serial Clock Output Enable */
 132#define CTR_TFSE	BIT(14)   /* Transmit Frame Sync Signal Output Enable */
 133#define CTR_TXE		BIT(9)    /* Transmit Enable */
 134#define CTR_RXE		BIT(8)    /* Receive Enable */
 135#define CTR_TXRST	BIT(1)    /* Transmit Reset */
 136#define CTR_RXRST	BIT(0)    /* Receive Reset */
 137
 138/* FCTR */
 139#define FCTR_TFWM_MASK	GENMASK(31, 29) /* Transmit FIFO Watermark */
 140#define FCTR_TFWM_64	(0 << 29) /*  Transfer Request when 64 empty stages */
 141#define FCTR_TFWM_32	(1 << 29) /*  Transfer Request when 32 empty stages */
 142#define FCTR_TFWM_24	(2 << 29) /*  Transfer Request when 24 empty stages */
 143#define FCTR_TFWM_16	(3 << 29) /*  Transfer Request when 16 empty stages */
 144#define FCTR_TFWM_12	(4 << 29) /*  Transfer Request when 12 empty stages */
 145#define FCTR_TFWM_8	(5 << 29) /*  Transfer Request when 8 empty stages */
 146#define FCTR_TFWM_4	(6 << 29) /*  Transfer Request when 4 empty stages */
 147#define FCTR_TFWM_1	(7 << 29) /*  Transfer Request when 1 empty stage */
 148#define FCTR_TFUA_MASK	GENMASK(26, 20) /* Transmit FIFO Usable Area */
 149#define FCTR_TFUA_SHIFT	20
 150#define FCTR_TFUA(i)	((i) << FCTR_TFUA_SHIFT)
 151#define FCTR_RFWM_MASK	GENMASK(15, 13) /* Receive FIFO Watermark */
 152#define FCTR_RFWM_1	(0 << 13) /*  Transfer Request when 1 valid stages */
 153#define FCTR_RFWM_4	(1 << 13) /*  Transfer Request when 4 valid stages */
 154#define FCTR_RFWM_8	(2 << 13) /*  Transfer Request when 8 valid stages */
 155#define FCTR_RFWM_16	(3 << 13) /*  Transfer Request when 16 valid stages */
 156#define FCTR_RFWM_32	(4 << 13) /*  Transfer Request when 32 valid stages */
 157#define FCTR_RFWM_64	(5 << 13) /*  Transfer Request when 64 valid stages */
 158#define FCTR_RFWM_128	(6 << 13) /*  Transfer Request when 128 valid stages */
 159#define FCTR_RFWM_256	(7 << 13) /*  Transfer Request when 256 valid stages */
 160#define FCTR_RFUA_MASK	GENMASK(12, 4) /* Receive FIFO Usable Area (0x40 = full) */
 161#define FCTR_RFUA_SHIFT	4
 162#define FCTR_RFUA(i)	((i) << FCTR_RFUA_SHIFT)
 163
 164/* STR */
 165#define STR_TFEMP	BIT(29) /* Transmit FIFO Empty */
 166#define STR_TDREQ	BIT(28) /* Transmit Data Transfer Request */
 167#define STR_TEOF	BIT(23) /* Frame Transmission End */
 168#define STR_TFSERR	BIT(21) /* Transmit Frame Synchronization Error */
 169#define STR_TFOVF	BIT(20) /* Transmit FIFO Overflow */
 170#define STR_TFUDF	BIT(19) /* Transmit FIFO Underflow */
 171#define STR_RFFUL	BIT(13) /* Receive FIFO Full */
 172#define STR_RDREQ	BIT(12) /* Receive Data Transfer Request */
 173#define STR_REOF	BIT(7)  /* Frame Reception End */
 174#define STR_RFSERR	BIT(5)  /* Receive Frame Synchronization Error */
 175#define STR_RFUDF	BIT(4)  /* Receive FIFO Underflow */
 176#define STR_RFOVF	BIT(3)  /* Receive FIFO Overflow */
 177
 178/* IER */
 179#define IER_TDMAE	BIT(31) /* Transmit Data DMA Transfer Req. Enable */
 180#define IER_TFEMPE	BIT(29) /* Transmit FIFO Empty Enable */
 181#define IER_TDREQE	BIT(28) /* Transmit Data Transfer Request Enable */
 182#define IER_TEOFE	BIT(23) /* Frame Transmission End Enable */
 183#define IER_TFSERRE	BIT(21) /* Transmit Frame Sync Error Enable */
 184#define IER_TFOVFE	BIT(20) /* Transmit FIFO Overflow Enable */
 185#define IER_TFUDFE	BIT(19) /* Transmit FIFO Underflow Enable */
 186#define IER_RDMAE	BIT(15) /* Receive Data DMA Transfer Req. Enable */
 187#define IER_RFFULE	BIT(13) /* Receive FIFO Full Enable */
 188#define IER_RDREQE	BIT(12) /* Receive Data Transfer Request Enable */
 189#define IER_REOFE	BIT(7)  /* Frame Reception End Enable */
 190#define IER_RFSERRE	BIT(5)  /* Receive Frame Sync Error Enable */
 191#define IER_RFUDFE	BIT(4)  /* Receive FIFO Underflow Enable */
 192#define IER_RFOVFE	BIT(3)  /* Receive FIFO Overflow Enable */
 193
 194
 195static u32 sh_msiof_read(struct sh_msiof_spi_priv *p, int reg_offs)
 196{
 197	switch (reg_offs) {
 198	case TSCR:
 199	case RSCR:
 200		return ioread16(p->mapbase + reg_offs);
 201	default:
 202		return ioread32(p->mapbase + reg_offs);
 203	}
 204}
 205
 206static void sh_msiof_write(struct sh_msiof_spi_priv *p, int reg_offs,
 207			   u32 value)
 208{
 209	switch (reg_offs) {
 210	case TSCR:
 211	case RSCR:
 212		iowrite16(value, p->mapbase + reg_offs);
 213		break;
 214	default:
 215		iowrite32(value, p->mapbase + reg_offs);
 216		break;
 217	}
 218}
 219
 220static int sh_msiof_modify_ctr_wait(struct sh_msiof_spi_priv *p,
 221				    u32 clr, u32 set)
 222{
 223	u32 mask = clr | set;
 224	u32 data;
 
 225
 226	data = sh_msiof_read(p, CTR);
 227	data &= ~clr;
 228	data |= set;
 229	sh_msiof_write(p, CTR, data);
 230
 231	return readl_poll_timeout_atomic(p->mapbase + CTR, data,
 232					 (data & mask) == set, 1, 100);
 
 
 
 
 
 
 233}
 234
 235static irqreturn_t sh_msiof_spi_irq(int irq, void *data)
 236{
 237	struct sh_msiof_spi_priv *p = data;
 238
 239	/* just disable the interrupt and wake up */
 240	sh_msiof_write(p, IER, 0);
 241	complete(&p->done);
 242
 243	return IRQ_HANDLED;
 244}
 245
 246static void sh_msiof_spi_reset_regs(struct sh_msiof_spi_priv *p)
 247{
 248	u32 mask = CTR_TXRST | CTR_RXRST;
 249	u32 data;
 250
 251	data = sh_msiof_read(p, CTR);
 252	data |= mask;
 253	sh_msiof_write(p, CTR, data);
 254
 255	readl_poll_timeout_atomic(p->mapbase + CTR, data, !(data & mask), 1,
 256				  100);
 257}
 258
 259static const u32 sh_msiof_spi_div_array[] = {
 260	SCR_BRDV_DIV_1, SCR_BRDV_DIV_2,	 SCR_BRDV_DIV_4,
 261	SCR_BRDV_DIV_8,	SCR_BRDV_DIV_16, SCR_BRDV_DIV_32,
 262};
 263
 264static void sh_msiof_spi_set_clk_regs(struct sh_msiof_spi_priv *p,
 265				      unsigned long parent_rate, u32 spi_hz)
 266{
 267	unsigned long div;
 268	u32 brps, scr;
 269	unsigned int div_pow = p->min_div_pow;
 270
 271	if (!spi_hz || !parent_rate) {
 272		WARN(1, "Invalid clock rate parameters %lu and %u\n",
 273		     parent_rate, spi_hz);
 274		return;
 275	}
 276
 277	div = DIV_ROUND_UP(parent_rate, spi_hz);
 278	if (div <= 1024) {
 279		/* SCR_BRDV_DIV_1 is valid only if BRPS is x 1/1 or x 1/2 */
 280		if (!div_pow && div <= 32 && div > 2)
 281			div_pow = 1;
 282
 283		if (div_pow)
 284			brps = (div + 1) >> div_pow;
 285		else
 286			brps = div;
 287
 288		for (; brps > 32; div_pow++)
 289			brps = (brps + 1) >> 1;
 290	} else {
 291		/* Set transfer rate composite divisor to 2^5 * 32 = 1024 */
 292		dev_err(&p->pdev->dev,
 293			"Requested SPI transfer rate %d is too low\n", spi_hz);
 294		div_pow = 5;
 295		brps = 32;
 296	}
 297
 298	scr = sh_msiof_spi_div_array[div_pow] | SCR_BRPS(brps);
 
 
 299	sh_msiof_write(p, TSCR, scr);
 300	if (!(p->ctlr->flags & SPI_CONTROLLER_MUST_TX))
 301		sh_msiof_write(p, RSCR, scr);
 302}
 303
 304static u32 sh_msiof_get_delay_bit(u32 dtdl_or_syncdl)
 305{
 306	/*
 307	 * DTDL/SYNCDL bit	: p->info->dtdl or p->info->syncdl
 308	 * b'000		: 0
 309	 * b'001		: 100
 310	 * b'010		: 200
 311	 * b'011 (SYNCDL only)	: 300
 312	 * b'101		: 50
 313	 * b'110		: 150
 314	 */
 315	if (dtdl_or_syncdl % 100)
 316		return dtdl_or_syncdl / 100 + 5;
 317	else
 318		return dtdl_or_syncdl / 100;
 319}
 320
 321static u32 sh_msiof_spi_get_dtdl_and_syncdl(struct sh_msiof_spi_priv *p)
 322{
 323	u32 val;
 324
 325	if (!p->info)
 326		return 0;
 327
 328	/* check if DTDL and SYNCDL is allowed value */
 329	if (p->info->dtdl > 200 || p->info->syncdl > 300) {
 330		dev_warn(&p->pdev->dev, "DTDL or SYNCDL is too large\n");
 331		return 0;
 332	}
 333
 334	/* check if the sum of DTDL and SYNCDL becomes an integer value  */
 335	if ((p->info->dtdl + p->info->syncdl) % 100) {
 336		dev_warn(&p->pdev->dev, "the sum of DTDL/SYNCDL is not good\n");
 337		return 0;
 338	}
 339
 340	val = sh_msiof_get_delay_bit(p->info->dtdl) << MDR1_DTDL_SHIFT;
 341	val |= sh_msiof_get_delay_bit(p->info->syncdl) << MDR1_SYNCDL_SHIFT;
 342
 343	return val;
 344}
 345
 346static void sh_msiof_spi_set_pin_regs(struct sh_msiof_spi_priv *p, u32 ss,
 347				      u32 cpol, u32 cpha,
 348				      u32 tx_hi_z, u32 lsb_first, u32 cs_high)
 349{
 350	u32 tmp;
 351	int edge;
 352
 353	/*
 354	 * CPOL CPHA     TSCKIZ RSCKIZ TEDG REDG
 355	 *    0    0         10     10    1    1
 356	 *    0    1         10     10    0    0
 357	 *    1    0         11     11    0    0
 358	 *    1    1         11     11    1    1
 359	 */
 360	tmp = MDR1_SYNCMD_SPI | 1 << MDR1_FLD_SHIFT | MDR1_XXSTP;
 361	tmp |= !cs_high << MDR1_SYNCAC_SHIFT;
 362	tmp |= lsb_first << MDR1_BITLSB_SHIFT;
 363	tmp |= sh_msiof_spi_get_dtdl_and_syncdl(p);
 364	if (spi_controller_is_slave(p->ctlr)) {
 365		sh_msiof_write(p, TMDR1, tmp | TMDR1_PCON);
 366	} else {
 367		sh_msiof_write(p, TMDR1,
 368			       tmp | MDR1_TRMD | TMDR1_PCON |
 369			       (ss < MAX_SS ? ss : 0) << TMDR1_SYNCCH_SHIFT);
 370	}
 371	if (p->ctlr->flags & SPI_CONTROLLER_MUST_TX) {
 372		/* These bits are reserved if RX needs TX */
 373		tmp &= ~0x0000ffff;
 374	}
 375	sh_msiof_write(p, RMDR1, tmp);
 376
 377	tmp = 0;
 378	tmp |= CTR_TSCKIZ_SCK | cpol << CTR_TSCKIZ_POL_SHIFT;
 379	tmp |= CTR_RSCKIZ_SCK | cpol << CTR_RSCKIZ_POL_SHIFT;
 380
 381	edge = cpol ^ !cpha;
 382
 383	tmp |= edge << CTR_TEDG_SHIFT;
 384	tmp |= edge << CTR_REDG_SHIFT;
 385	tmp |= tx_hi_z ? CTR_TXDIZ_HIZ : CTR_TXDIZ_LOW;
 386	sh_msiof_write(p, CTR, tmp);
 387}
 388
 389static void sh_msiof_spi_set_mode_regs(struct sh_msiof_spi_priv *p,
 390				       const void *tx_buf, void *rx_buf,
 391				       u32 bits, u32 words)
 392{
 393	u32 dr2 = MDR2_BITLEN1(bits) | MDR2_WDLEN1(words);
 394
 395	if (tx_buf || (p->ctlr->flags & SPI_CONTROLLER_MUST_TX))
 396		sh_msiof_write(p, TMDR2, dr2);
 397	else
 398		sh_msiof_write(p, TMDR2, dr2 | MDR2_GRPMASK1);
 399
 400	if (rx_buf)
 401		sh_msiof_write(p, RMDR2, dr2);
 402}
 403
 404static void sh_msiof_reset_str(struct sh_msiof_spi_priv *p)
 405{
 406	sh_msiof_write(p, STR,
 407		       sh_msiof_read(p, STR) & ~(STR_TDREQ | STR_RDREQ));
 408}
 409
 410static void sh_msiof_spi_write_fifo_8(struct sh_msiof_spi_priv *p,
 411				      const void *tx_buf, int words, int fs)
 412{
 413	const u8 *buf_8 = tx_buf;
 414	int k;
 415
 416	for (k = 0; k < words; k++)
 417		sh_msiof_write(p, TFDR, buf_8[k] << fs);
 418}
 419
 420static void sh_msiof_spi_write_fifo_16(struct sh_msiof_spi_priv *p,
 421				       const void *tx_buf, int words, int fs)
 422{
 423	const u16 *buf_16 = tx_buf;
 424	int k;
 425
 426	for (k = 0; k < words; k++)
 427		sh_msiof_write(p, TFDR, buf_16[k] << fs);
 428}
 429
 430static void sh_msiof_spi_write_fifo_16u(struct sh_msiof_spi_priv *p,
 431					const void *tx_buf, int words, int fs)
 432{
 433	const u16 *buf_16 = tx_buf;
 434	int k;
 435
 436	for (k = 0; k < words; k++)
 437		sh_msiof_write(p, TFDR, get_unaligned(&buf_16[k]) << fs);
 438}
 439
 440static void sh_msiof_spi_write_fifo_32(struct sh_msiof_spi_priv *p,
 441				       const void *tx_buf, int words, int fs)
 442{
 443	const u32 *buf_32 = tx_buf;
 444	int k;
 445
 446	for (k = 0; k < words; k++)
 447		sh_msiof_write(p, TFDR, buf_32[k] << fs);
 448}
 449
 450static void sh_msiof_spi_write_fifo_32u(struct sh_msiof_spi_priv *p,
 451					const void *tx_buf, int words, int fs)
 452{
 453	const u32 *buf_32 = tx_buf;
 454	int k;
 455
 456	for (k = 0; k < words; k++)
 457		sh_msiof_write(p, TFDR, get_unaligned(&buf_32[k]) << fs);
 458}
 459
 460static void sh_msiof_spi_write_fifo_s32(struct sh_msiof_spi_priv *p,
 461					const void *tx_buf, int words, int fs)
 462{
 463	const u32 *buf_32 = tx_buf;
 464	int k;
 465
 466	for (k = 0; k < words; k++)
 467		sh_msiof_write(p, TFDR, swab32(buf_32[k] << fs));
 468}
 469
 470static void sh_msiof_spi_write_fifo_s32u(struct sh_msiof_spi_priv *p,
 471					 const void *tx_buf, int words, int fs)
 472{
 473	const u32 *buf_32 = tx_buf;
 474	int k;
 475
 476	for (k = 0; k < words; k++)
 477		sh_msiof_write(p, TFDR, swab32(get_unaligned(&buf_32[k]) << fs));
 478}
 479
 480static void sh_msiof_spi_read_fifo_8(struct sh_msiof_spi_priv *p,
 481				     void *rx_buf, int words, int fs)
 482{
 483	u8 *buf_8 = rx_buf;
 484	int k;
 485
 486	for (k = 0; k < words; k++)
 487		buf_8[k] = sh_msiof_read(p, RFDR) >> fs;
 488}
 489
 490static void sh_msiof_spi_read_fifo_16(struct sh_msiof_spi_priv *p,
 491				      void *rx_buf, int words, int fs)
 492{
 493	u16 *buf_16 = rx_buf;
 494	int k;
 495
 496	for (k = 0; k < words; k++)
 497		buf_16[k] = sh_msiof_read(p, RFDR) >> fs;
 498}
 499
 500static void sh_msiof_spi_read_fifo_16u(struct sh_msiof_spi_priv *p,
 501				       void *rx_buf, int words, int fs)
 502{
 503	u16 *buf_16 = rx_buf;
 504	int k;
 505
 506	for (k = 0; k < words; k++)
 507		put_unaligned(sh_msiof_read(p, RFDR) >> fs, &buf_16[k]);
 508}
 509
 510static void sh_msiof_spi_read_fifo_32(struct sh_msiof_spi_priv *p,
 511				      void *rx_buf, int words, int fs)
 512{
 513	u32 *buf_32 = rx_buf;
 514	int k;
 515
 516	for (k = 0; k < words; k++)
 517		buf_32[k] = sh_msiof_read(p, RFDR) >> fs;
 518}
 519
 520static void sh_msiof_spi_read_fifo_32u(struct sh_msiof_spi_priv *p,
 521				       void *rx_buf, int words, int fs)
 522{
 523	u32 *buf_32 = rx_buf;
 524	int k;
 525
 526	for (k = 0; k < words; k++)
 527		put_unaligned(sh_msiof_read(p, RFDR) >> fs, &buf_32[k]);
 528}
 529
 530static void sh_msiof_spi_read_fifo_s32(struct sh_msiof_spi_priv *p,
 531				       void *rx_buf, int words, int fs)
 532{
 533	u32 *buf_32 = rx_buf;
 534	int k;
 535
 536	for (k = 0; k < words; k++)
 537		buf_32[k] = swab32(sh_msiof_read(p, RFDR) >> fs);
 538}
 539
 540static void sh_msiof_spi_read_fifo_s32u(struct sh_msiof_spi_priv *p,
 541				       void *rx_buf, int words, int fs)
 542{
 543	u32 *buf_32 = rx_buf;
 544	int k;
 545
 546	for (k = 0; k < words; k++)
 547		put_unaligned(swab32(sh_msiof_read(p, RFDR) >> fs), &buf_32[k]);
 548}
 549
 550static int sh_msiof_spi_setup(struct spi_device *spi)
 551{
 552	struct sh_msiof_spi_priv *p =
 553		spi_controller_get_devdata(spi->controller);
 554	u32 clr, set, tmp;
 555
 556	if (spi->cs_gpiod || spi_controller_is_slave(p->ctlr))
 557		return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 558
 559	if (p->native_cs_inited &&
 560	    (p->native_cs_high == !!(spi->mode & SPI_CS_HIGH)))
 561		return 0;
 562
 563	/* Configure native chip select mode/polarity early */
 564	clr = MDR1_SYNCMD_MASK;
 565	set = MDR1_SYNCMD_SPI;
 566	if (spi->mode & SPI_CS_HIGH)
 567		clr |= BIT(MDR1_SYNCAC_SHIFT);
 568	else
 569		set |= BIT(MDR1_SYNCAC_SHIFT);
 570	pm_runtime_get_sync(&p->pdev->dev);
 571	tmp = sh_msiof_read(p, TMDR1) & ~clr;
 572	sh_msiof_write(p, TMDR1, tmp | set | MDR1_TRMD | TMDR1_PCON);
 573	tmp = sh_msiof_read(p, RMDR1) & ~clr;
 574	sh_msiof_write(p, RMDR1, tmp | set);
 575	pm_runtime_put(&p->pdev->dev);
 576	p->native_cs_high = spi->mode & SPI_CS_HIGH;
 577	p->native_cs_inited = true;
 578	return 0;
 579}
 580
 581static int sh_msiof_prepare_message(struct spi_controller *ctlr,
 582				    struct spi_message *msg)
 583{
 584	struct sh_msiof_spi_priv *p = spi_controller_get_devdata(ctlr);
 585	const struct spi_device *spi = msg->spi;
 586	u32 ss, cs_high;
 587
 588	/* Configure pins before asserting CS */
 589	if (spi->cs_gpiod) {
 590		ss = p->unused_ss;
 591		cs_high = p->native_cs_high;
 592	} else {
 593		ss = spi->chip_select;
 594		cs_high = !!(spi->mode & SPI_CS_HIGH);
 595	}
 596	sh_msiof_spi_set_pin_regs(p, ss, !!(spi->mode & SPI_CPOL),
 597				  !!(spi->mode & SPI_CPHA),
 598				  !!(spi->mode & SPI_3WIRE),
 599				  !!(spi->mode & SPI_LSB_FIRST), cs_high);
 
 600	return 0;
 601}
 602
 603static int sh_msiof_spi_start(struct sh_msiof_spi_priv *p, void *rx_buf)
 604{
 605	bool slave = spi_controller_is_slave(p->ctlr);
 606	int ret = 0;
 607
 608	/* setup clock and rx/tx signals */
 609	if (!slave)
 610		ret = sh_msiof_modify_ctr_wait(p, 0, CTR_TSCKE);
 611	if (rx_buf && !ret)
 612		ret = sh_msiof_modify_ctr_wait(p, 0, CTR_RXE);
 613	if (!ret)
 614		ret = sh_msiof_modify_ctr_wait(p, 0, CTR_TXE);
 615
 616	/* start by setting frame bit */
 617	if (!ret && !slave)
 618		ret = sh_msiof_modify_ctr_wait(p, 0, CTR_TFSE);
 619
 620	return ret;
 621}
 622
 623static int sh_msiof_spi_stop(struct sh_msiof_spi_priv *p, void *rx_buf)
 624{
 625	bool slave = spi_controller_is_slave(p->ctlr);
 626	int ret = 0;
 627
 628	/* shut down frame, rx/tx and clock signals */
 629	if (!slave)
 630		ret = sh_msiof_modify_ctr_wait(p, CTR_TFSE, 0);
 631	if (!ret)
 632		ret = sh_msiof_modify_ctr_wait(p, CTR_TXE, 0);
 633	if (rx_buf && !ret)
 634		ret = sh_msiof_modify_ctr_wait(p, CTR_RXE, 0);
 635	if (!ret && !slave)
 636		ret = sh_msiof_modify_ctr_wait(p, CTR_TSCKE, 0);
 637
 638	return ret;
 639}
 640
 641static int sh_msiof_slave_abort(struct spi_controller *ctlr)
 642{
 643	struct sh_msiof_spi_priv *p = spi_controller_get_devdata(ctlr);
 644
 645	p->slave_aborted = true;
 646	complete(&p->done);
 647	complete(&p->done_txdma);
 648	return 0;
 649}
 650
 651static int sh_msiof_wait_for_completion(struct sh_msiof_spi_priv *p,
 652					struct completion *x)
 653{
 654	if (spi_controller_is_slave(p->ctlr)) {
 655		if (wait_for_completion_interruptible(x) ||
 656		    p->slave_aborted) {
 657			dev_dbg(&p->pdev->dev, "interrupted\n");
 658			return -EINTR;
 659		}
 660	} else {
 661		if (!wait_for_completion_timeout(x, HZ)) {
 662			dev_err(&p->pdev->dev, "timeout\n");
 663			return -ETIMEDOUT;
 664		}
 665	}
 666
 667	return 0;
 668}
 669
 670static int sh_msiof_spi_txrx_once(struct sh_msiof_spi_priv *p,
 671				  void (*tx_fifo)(struct sh_msiof_spi_priv *,
 672						  const void *, int, int),
 673				  void (*rx_fifo)(struct sh_msiof_spi_priv *,
 674						  void *, int, int),
 675				  const void *tx_buf, void *rx_buf,
 676				  int words, int bits)
 677{
 678	int fifo_shift;
 679	int ret;
 680
 681	/* limit maximum word transfer to rx/tx fifo size */
 682	if (tx_buf)
 683		words = min_t(int, words, p->tx_fifo_size);
 684	if (rx_buf)
 685		words = min_t(int, words, p->rx_fifo_size);
 686
 687	/* the fifo contents need shifting */
 688	fifo_shift = 32 - bits;
 689
 690	/* default FIFO watermarks for PIO */
 691	sh_msiof_write(p, FCTR, 0);
 692
 693	/* setup msiof transfer mode registers */
 694	sh_msiof_spi_set_mode_regs(p, tx_buf, rx_buf, bits, words);
 695	sh_msiof_write(p, IER, IER_TEOFE | IER_REOFE);
 696
 697	/* write tx fifo */
 698	if (tx_buf)
 699		tx_fifo(p, tx_buf, words, fifo_shift);
 700
 701	reinit_completion(&p->done);
 702	p->slave_aborted = false;
 703
 704	ret = sh_msiof_spi_start(p, rx_buf);
 705	if (ret) {
 706		dev_err(&p->pdev->dev, "failed to start hardware\n");
 707		goto stop_ier;
 708	}
 709
 710	/* wait for tx fifo to be emptied / rx fifo to be filled */
 711	ret = sh_msiof_wait_for_completion(p, &p->done);
 712	if (ret)
 
 713		goto stop_reset;
 
 714
 715	/* read rx fifo */
 716	if (rx_buf)
 717		rx_fifo(p, rx_buf, words, fifo_shift);
 718
 719	/* clear status bits */
 720	sh_msiof_reset_str(p);
 721
 722	ret = sh_msiof_spi_stop(p, rx_buf);
 723	if (ret) {
 724		dev_err(&p->pdev->dev, "failed to shut down hardware\n");
 725		return ret;
 726	}
 727
 728	return words;
 729
 730stop_reset:
 731	sh_msiof_reset_str(p);
 732	sh_msiof_spi_stop(p, rx_buf);
 733stop_ier:
 734	sh_msiof_write(p, IER, 0);
 735	return ret;
 736}
 737
 738static void sh_msiof_dma_complete(void *arg)
 739{
 740	complete(arg);
 
 
 
 741}
 742
 743static int sh_msiof_dma_once(struct sh_msiof_spi_priv *p, const void *tx,
 744			     void *rx, unsigned int len)
 745{
 746	u32 ier_bits = 0;
 747	struct dma_async_tx_descriptor *desc_tx = NULL, *desc_rx = NULL;
 748	dma_cookie_t cookie;
 749	int ret;
 750
 751	/* First prepare and submit the DMA request(s), as this may fail */
 752	if (rx) {
 753		ier_bits |= IER_RDREQE | IER_RDMAE;
 754		desc_rx = dmaengine_prep_slave_single(p->ctlr->dma_rx,
 755					p->rx_dma_addr, len, DMA_DEV_TO_MEM,
 756					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 757		if (!desc_rx)
 758			return -EAGAIN;
 759
 760		desc_rx->callback = sh_msiof_dma_complete;
 761		desc_rx->callback_param = &p->done;
 762		cookie = dmaengine_submit(desc_rx);
 763		if (dma_submit_error(cookie))
 764			return cookie;
 765	}
 766
 767	if (tx) {
 768		ier_bits |= IER_TDREQE | IER_TDMAE;
 769		dma_sync_single_for_device(p->ctlr->dma_tx->device->dev,
 770					   p->tx_dma_addr, len, DMA_TO_DEVICE);
 771		desc_tx = dmaengine_prep_slave_single(p->ctlr->dma_tx,
 772					p->tx_dma_addr, len, DMA_MEM_TO_DEV,
 773					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 774		if (!desc_tx) {
 775			ret = -EAGAIN;
 776			goto no_dma_tx;
 777		}
 778
 779		desc_tx->callback = sh_msiof_dma_complete;
 780		desc_tx->callback_param = &p->done_txdma;
 
 
 
 
 
 781		cookie = dmaengine_submit(desc_tx);
 782		if (dma_submit_error(cookie)) {
 783			ret = cookie;
 784			goto no_dma_tx;
 785		}
 786	}
 787
 788	/* 1 stage FIFO watermarks for DMA */
 789	sh_msiof_write(p, FCTR, FCTR_TFWM_1 | FCTR_RFWM_1);
 790
 791	/* setup msiof transfer mode registers (32-bit words) */
 792	sh_msiof_spi_set_mode_regs(p, tx, rx, 32, len / 4);
 793
 794	sh_msiof_write(p, IER, ier_bits);
 795
 796	reinit_completion(&p->done);
 797	if (tx)
 798		reinit_completion(&p->done_txdma);
 799	p->slave_aborted = false;
 800
 801	/* Now start DMA */
 802	if (rx)
 803		dma_async_issue_pending(p->ctlr->dma_rx);
 804	if (tx)
 805		dma_async_issue_pending(p->ctlr->dma_tx);
 806
 807	ret = sh_msiof_spi_start(p, rx);
 808	if (ret) {
 809		dev_err(&p->pdev->dev, "failed to start hardware\n");
 810		goto stop_dma;
 811	}
 812
 813	if (tx) {
 814		/* wait for tx DMA completion */
 815		ret = sh_msiof_wait_for_completion(p, &p->done_txdma);
 816		if (ret)
 817			goto stop_reset;
 818	}
 819
 820	if (rx) {
 821		/* wait for rx DMA completion */
 822		ret = sh_msiof_wait_for_completion(p, &p->done);
 823		if (ret)
 824			goto stop_reset;
 825
 826		sh_msiof_write(p, IER, 0);
 827	} else {
 828		/* wait for tx fifo to be emptied */
 829		sh_msiof_write(p, IER, IER_TEOFE);
 830		ret = sh_msiof_wait_for_completion(p, &p->done);
 831		if (ret)
 832			goto stop_reset;
 833	}
 834
 835	/* clear status bits */
 836	sh_msiof_reset_str(p);
 837
 838	ret = sh_msiof_spi_stop(p, rx);
 839	if (ret) {
 840		dev_err(&p->pdev->dev, "failed to shut down hardware\n");
 841		return ret;
 842	}
 843
 844	if (rx)
 845		dma_sync_single_for_cpu(p->ctlr->dma_rx->device->dev,
 846					p->rx_dma_addr, len, DMA_FROM_DEVICE);
 
 847
 848	return 0;
 849
 850stop_reset:
 851	sh_msiof_reset_str(p);
 852	sh_msiof_spi_stop(p, rx);
 853stop_dma:
 854	if (tx)
 855		dmaengine_terminate_all(p->ctlr->dma_tx);
 856no_dma_tx:
 857	if (rx)
 858		dmaengine_terminate_all(p->ctlr->dma_rx);
 859	sh_msiof_write(p, IER, 0);
 860	return ret;
 861}
 862
 863static void copy_bswap32(u32 *dst, const u32 *src, unsigned int words)
 864{
 865	/* src or dst can be unaligned, but not both */
 866	if ((unsigned long)src & 3) {
 867		while (words--) {
 868			*dst++ = swab32(get_unaligned(src));
 869			src++;
 870		}
 871	} else if ((unsigned long)dst & 3) {
 872		while (words--) {
 873			put_unaligned(swab32(*src++), dst);
 874			dst++;
 875		}
 876	} else {
 877		while (words--)
 878			*dst++ = swab32(*src++);
 879	}
 880}
 881
 882static void copy_wswap32(u32 *dst, const u32 *src, unsigned int words)
 883{
 884	/* src or dst can be unaligned, but not both */
 885	if ((unsigned long)src & 3) {
 886		while (words--) {
 887			*dst++ = swahw32(get_unaligned(src));
 888			src++;
 889		}
 890	} else if ((unsigned long)dst & 3) {
 891		while (words--) {
 892			put_unaligned(swahw32(*src++), dst);
 893			dst++;
 894		}
 895	} else {
 896		while (words--)
 897			*dst++ = swahw32(*src++);
 898	}
 899}
 900
 901static void copy_plain32(u32 *dst, const u32 *src, unsigned int words)
 902{
 903	memcpy(dst, src, words * 4);
 904}
 905
 906static int sh_msiof_transfer_one(struct spi_controller *ctlr,
 907				 struct spi_device *spi,
 908				 struct spi_transfer *t)
 909{
 910	struct sh_msiof_spi_priv *p = spi_controller_get_devdata(ctlr);
 911	void (*copy32)(u32 *, const u32 *, unsigned int);
 912	void (*tx_fifo)(struct sh_msiof_spi_priv *, const void *, int, int);
 913	void (*rx_fifo)(struct sh_msiof_spi_priv *, void *, int, int);
 914	const void *tx_buf = t->tx_buf;
 915	void *rx_buf = t->rx_buf;
 916	unsigned int len = t->len;
 917	unsigned int bits = t->bits_per_word;
 918	unsigned int bytes_per_word;
 919	unsigned int words;
 920	int n;
 921	bool swab;
 922	int ret;
 923
 924	/* reset registers */
 925	sh_msiof_spi_reset_regs(p);
 926
 927	/* setup clocks (clock already enabled in chipselect()) */
 928	if (!spi_controller_is_slave(p->ctlr))
 929		sh_msiof_spi_set_clk_regs(p, clk_get_rate(p->clk), t->speed_hz);
 930
 931	while (ctlr->dma_tx && len > 15) {
 932		/*
 933		 *  DMA supports 32-bit words only, hence pack 8-bit and 16-bit
 934		 *  words, with byte resp. word swapping.
 935		 */
 936		unsigned int l = 0;
 937
 938		if (tx_buf)
 939			l = min(round_down(len, 4), p->tx_fifo_size * 4);
 940		if (rx_buf)
 941			l = min(round_down(len, 4), p->rx_fifo_size * 4);
 942
 943		if (bits <= 8) {
 
 
 944			copy32 = copy_bswap32;
 945		} else if (bits <= 16) {
 
 
 946			copy32 = copy_wswap32;
 947		} else {
 948			copy32 = copy_plain32;
 949		}
 950
 951		if (tx_buf)
 952			copy32(p->tx_dma_page, tx_buf, l / 4);
 953
 954		ret = sh_msiof_dma_once(p, tx_buf, rx_buf, l);
 955		if (ret == -EAGAIN) {
 956			dev_warn_once(&p->pdev->dev,
 957				"DMA not available, falling back to PIO\n");
 
 958			break;
 959		}
 960		if (ret)
 961			return ret;
 962
 963		if (rx_buf) {
 964			copy32(rx_buf, p->rx_dma_page, l / 4);
 965			rx_buf += l;
 966		}
 967		if (tx_buf)
 968			tx_buf += l;
 969
 970		len -= l;
 971		if (!len)
 972			return 0;
 973	}
 974
 975	if (bits <= 8 && len > 15) {
 976		bits = 32;
 977		swab = true;
 978	} else {
 979		swab = false;
 980	}
 981
 982	/* setup bytes per word and fifo read/write functions */
 983	if (bits <= 8) {
 984		bytes_per_word = 1;
 985		tx_fifo = sh_msiof_spi_write_fifo_8;
 986		rx_fifo = sh_msiof_spi_read_fifo_8;
 987	} else if (bits <= 16) {
 988		bytes_per_word = 2;
 989		if ((unsigned long)tx_buf & 0x01)
 990			tx_fifo = sh_msiof_spi_write_fifo_16u;
 991		else
 992			tx_fifo = sh_msiof_spi_write_fifo_16;
 993
 994		if ((unsigned long)rx_buf & 0x01)
 995			rx_fifo = sh_msiof_spi_read_fifo_16u;
 996		else
 997			rx_fifo = sh_msiof_spi_read_fifo_16;
 998	} else if (swab) {
 999		bytes_per_word = 4;
1000		if ((unsigned long)tx_buf & 0x03)
1001			tx_fifo = sh_msiof_spi_write_fifo_s32u;
1002		else
1003			tx_fifo = sh_msiof_spi_write_fifo_s32;
1004
1005		if ((unsigned long)rx_buf & 0x03)
1006			rx_fifo = sh_msiof_spi_read_fifo_s32u;
1007		else
1008			rx_fifo = sh_msiof_spi_read_fifo_s32;
1009	} else {
1010		bytes_per_word = 4;
1011		if ((unsigned long)tx_buf & 0x03)
1012			tx_fifo = sh_msiof_spi_write_fifo_32u;
1013		else
1014			tx_fifo = sh_msiof_spi_write_fifo_32;
1015
1016		if ((unsigned long)rx_buf & 0x03)
1017			rx_fifo = sh_msiof_spi_read_fifo_32u;
1018		else
1019			rx_fifo = sh_msiof_spi_read_fifo_32;
1020	}
1021
1022	/* transfer in fifo sized chunks */
1023	words = len / bytes_per_word;
1024
1025	while (words > 0) {
1026		n = sh_msiof_spi_txrx_once(p, tx_fifo, rx_fifo, tx_buf, rx_buf,
1027					   words, bits);
1028		if (n < 0)
1029			return n;
1030
1031		if (tx_buf)
1032			tx_buf += n * bytes_per_word;
1033		if (rx_buf)
1034			rx_buf += n * bytes_per_word;
1035		words -= n;
1036
1037		if (words == 0 && (len % bytes_per_word)) {
1038			words = len % bytes_per_word;
1039			bits = t->bits_per_word;
1040			bytes_per_word = 1;
1041			tx_fifo = sh_msiof_spi_write_fifo_8;
1042			rx_fifo = sh_msiof_spi_read_fifo_8;
1043		}
1044	}
1045
1046	return 0;
1047}
1048
1049static const struct sh_msiof_chipdata sh_data = {
1050	.bits_per_word_mask = SPI_BPW_RANGE_MASK(8, 32),
1051	.tx_fifo_size = 64,
1052	.rx_fifo_size = 64,
1053	.ctlr_flags = 0,
1054	.min_div_pow = 0,
1055};
1056
1057static const struct sh_msiof_chipdata rcar_gen2_data = {
1058	.bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(16) |
1059			      SPI_BPW_MASK(24) | SPI_BPW_MASK(32),
1060	.tx_fifo_size = 64,
1061	.rx_fifo_size = 64,
1062	.ctlr_flags = SPI_CONTROLLER_MUST_TX,
1063	.min_div_pow = 0,
1064};
1065
1066static const struct sh_msiof_chipdata rcar_gen3_data = {
1067	.bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(16) |
1068			      SPI_BPW_MASK(24) | SPI_BPW_MASK(32),
1069	.tx_fifo_size = 64,
1070	.rx_fifo_size = 64,
1071	.ctlr_flags = SPI_CONTROLLER_MUST_TX,
1072	.min_div_pow = 1,
1073};
1074
1075static const struct of_device_id sh_msiof_match[] = {
1076	{ .compatible = "renesas,sh-mobile-msiof", .data = &sh_data },
1077	{ .compatible = "renesas,msiof-r8a7743",   .data = &rcar_gen2_data },
1078	{ .compatible = "renesas,msiof-r8a7745",   .data = &rcar_gen2_data },
1079	{ .compatible = "renesas,msiof-r8a7790",   .data = &rcar_gen2_data },
1080	{ .compatible = "renesas,msiof-r8a7791",   .data = &rcar_gen2_data },
1081	{ .compatible = "renesas,msiof-r8a7792",   .data = &rcar_gen2_data },
1082	{ .compatible = "renesas,msiof-r8a7793",   .data = &rcar_gen2_data },
1083	{ .compatible = "renesas,msiof-r8a7794",   .data = &rcar_gen2_data },
1084	{ .compatible = "renesas,rcar-gen2-msiof", .data = &rcar_gen2_data },
1085	{ .compatible = "renesas,msiof-r8a7796",   .data = &rcar_gen3_data },
1086	{ .compatible = "renesas,rcar-gen3-msiof", .data = &rcar_gen3_data },
1087	{ .compatible = "renesas,sh-msiof",        .data = &sh_data }, /* Deprecated */
1088	{},
1089};
1090MODULE_DEVICE_TABLE(of, sh_msiof_match);
1091
1092#ifdef CONFIG_OF
1093static struct sh_msiof_spi_info *sh_msiof_spi_parse_dt(struct device *dev)
1094{
1095	struct sh_msiof_spi_info *info;
1096	struct device_node *np = dev->of_node;
1097	u32 num_cs = 1;
1098
1099	info = devm_kzalloc(dev, sizeof(struct sh_msiof_spi_info), GFP_KERNEL);
1100	if (!info)
1101		return NULL;
1102
1103	info->mode = of_property_read_bool(np, "spi-slave") ? MSIOF_SPI_SLAVE
1104							    : MSIOF_SPI_MASTER;
1105
1106	/* Parse the MSIOF properties */
1107	if (info->mode == MSIOF_SPI_MASTER)
1108		of_property_read_u32(np, "num-cs", &num_cs);
1109	of_property_read_u32(np, "renesas,tx-fifo-size",
1110					&info->tx_fifo_override);
1111	of_property_read_u32(np, "renesas,rx-fifo-size",
1112					&info->rx_fifo_override);
1113	of_property_read_u32(np, "renesas,dtdl", &info->dtdl);
1114	of_property_read_u32(np, "renesas,syncdl", &info->syncdl);
1115
1116	info->num_chipselect = num_cs;
1117
1118	return info;
1119}
1120#else
1121static struct sh_msiof_spi_info *sh_msiof_spi_parse_dt(struct device *dev)
1122{
1123	return NULL;
1124}
1125#endif
1126
1127static int sh_msiof_get_cs_gpios(struct sh_msiof_spi_priv *p)
1128{
1129	struct device *dev = &p->pdev->dev;
1130	unsigned int used_ss_mask = 0;
1131	unsigned int cs_gpios = 0;
1132	unsigned int num_cs, i;
1133	int ret;
1134
1135	ret = gpiod_count(dev, "cs");
1136	if (ret <= 0)
1137		return 0;
1138
1139	num_cs = max_t(unsigned int, ret, p->ctlr->num_chipselect);
1140	for (i = 0; i < num_cs; i++) {
1141		struct gpio_desc *gpiod;
1142
1143		gpiod = devm_gpiod_get_index(dev, "cs", i, GPIOD_ASIS);
1144		if (!IS_ERR(gpiod)) {
1145			devm_gpiod_put(dev, gpiod);
1146			cs_gpios++;
1147			continue;
1148		}
1149
1150		if (PTR_ERR(gpiod) != -ENOENT)
1151			return PTR_ERR(gpiod);
1152
1153		if (i >= MAX_SS) {
1154			dev_err(dev, "Invalid native chip select %d\n", i);
1155			return -EINVAL;
1156		}
1157		used_ss_mask |= BIT(i);
1158	}
1159	p->unused_ss = ffz(used_ss_mask);
1160	if (cs_gpios && p->unused_ss >= MAX_SS) {
1161		dev_err(dev, "No unused native chip select available\n");
1162		return -EINVAL;
1163	}
1164	return 0;
1165}
1166
1167static struct dma_chan *sh_msiof_request_dma_chan(struct device *dev,
1168	enum dma_transfer_direction dir, unsigned int id, dma_addr_t port_addr)
1169{
1170	dma_cap_mask_t mask;
1171	struct dma_chan *chan;
1172	struct dma_slave_config cfg;
1173	int ret;
1174
1175	dma_cap_zero(mask);
1176	dma_cap_set(DMA_SLAVE, mask);
1177
1178	chan = dma_request_slave_channel_compat(mask, shdma_chan_filter,
1179				(void *)(unsigned long)id, dev,
1180				dir == DMA_MEM_TO_DEV ? "tx" : "rx");
1181	if (!chan) {
1182		dev_warn(dev, "dma_request_slave_channel_compat failed\n");
1183		return NULL;
1184	}
1185
1186	memset(&cfg, 0, sizeof(cfg));
1187	cfg.direction = dir;
1188	if (dir == DMA_MEM_TO_DEV) {
1189		cfg.dst_addr = port_addr;
1190		cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1191	} else {
1192		cfg.src_addr = port_addr;
1193		cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1194	}
1195
1196	ret = dmaengine_slave_config(chan, &cfg);
1197	if (ret) {
1198		dev_warn(dev, "dmaengine_slave_config failed %d\n", ret);
1199		dma_release_channel(chan);
1200		return NULL;
1201	}
1202
1203	return chan;
1204}
1205
1206static int sh_msiof_request_dma(struct sh_msiof_spi_priv *p)
1207{
1208	struct platform_device *pdev = p->pdev;
1209	struct device *dev = &pdev->dev;
1210	const struct sh_msiof_spi_info *info = p->info;
1211	unsigned int dma_tx_id, dma_rx_id;
1212	const struct resource *res;
1213	struct spi_controller *ctlr;
1214	struct device *tx_dev, *rx_dev;
1215
1216	if (dev->of_node) {
1217		/* In the OF case we will get the slave IDs from the DT */
1218		dma_tx_id = 0;
1219		dma_rx_id = 0;
1220	} else if (info && info->dma_tx_id && info->dma_rx_id) {
1221		dma_tx_id = info->dma_tx_id;
1222		dma_rx_id = info->dma_rx_id;
1223	} else {
1224		/* The driver assumes no error */
1225		return 0;
1226	}
1227
1228	/* The DMA engine uses the second register set, if present */
1229	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
1230	if (!res)
1231		res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1232
1233	ctlr = p->ctlr;
1234	ctlr->dma_tx = sh_msiof_request_dma_chan(dev, DMA_MEM_TO_DEV,
1235						 dma_tx_id, res->start + TFDR);
1236	if (!ctlr->dma_tx)
 
1237		return -ENODEV;
1238
1239	ctlr->dma_rx = sh_msiof_request_dma_chan(dev, DMA_DEV_TO_MEM,
1240						 dma_rx_id, res->start + RFDR);
1241	if (!ctlr->dma_rx)
 
1242		goto free_tx_chan;
1243
1244	p->tx_dma_page = (void *)__get_free_page(GFP_KERNEL | GFP_DMA);
1245	if (!p->tx_dma_page)
1246		goto free_rx_chan;
1247
1248	p->rx_dma_page = (void *)__get_free_page(GFP_KERNEL | GFP_DMA);
1249	if (!p->rx_dma_page)
1250		goto free_tx_page;
1251
1252	tx_dev = ctlr->dma_tx->device->dev;
1253	p->tx_dma_addr = dma_map_single(tx_dev, p->tx_dma_page, PAGE_SIZE,
1254					DMA_TO_DEVICE);
1255	if (dma_mapping_error(tx_dev, p->tx_dma_addr))
1256		goto free_rx_page;
1257
1258	rx_dev = ctlr->dma_rx->device->dev;
1259	p->rx_dma_addr = dma_map_single(rx_dev, p->rx_dma_page, PAGE_SIZE,
1260					DMA_FROM_DEVICE);
1261	if (dma_mapping_error(rx_dev, p->rx_dma_addr))
1262		goto unmap_tx_page;
1263
1264	dev_info(dev, "DMA available");
1265	return 0;
1266
1267unmap_tx_page:
1268	dma_unmap_single(tx_dev, p->tx_dma_addr, PAGE_SIZE, DMA_TO_DEVICE);
1269free_rx_page:
1270	free_page((unsigned long)p->rx_dma_page);
1271free_tx_page:
1272	free_page((unsigned long)p->tx_dma_page);
1273free_rx_chan:
1274	dma_release_channel(ctlr->dma_rx);
1275free_tx_chan:
1276	dma_release_channel(ctlr->dma_tx);
1277	ctlr->dma_tx = NULL;
1278	return -ENODEV;
1279}
1280
1281static void sh_msiof_release_dma(struct sh_msiof_spi_priv *p)
1282{
1283	struct spi_controller *ctlr = p->ctlr;
 
1284
1285	if (!ctlr->dma_tx)
1286		return;
1287
1288	dma_unmap_single(ctlr->dma_rx->device->dev, p->rx_dma_addr, PAGE_SIZE,
1289			 DMA_FROM_DEVICE);
1290	dma_unmap_single(ctlr->dma_tx->device->dev, p->tx_dma_addr, PAGE_SIZE,
1291			 DMA_TO_DEVICE);
 
1292	free_page((unsigned long)p->rx_dma_page);
1293	free_page((unsigned long)p->tx_dma_page);
1294	dma_release_channel(ctlr->dma_rx);
1295	dma_release_channel(ctlr->dma_tx);
1296}
1297
1298static int sh_msiof_spi_probe(struct platform_device *pdev)
1299{
1300	struct spi_controller *ctlr;
 
1301	const struct sh_msiof_chipdata *chipdata;
1302	struct sh_msiof_spi_info *info;
1303	struct sh_msiof_spi_priv *p;
1304	int i;
1305	int ret;
1306
1307	chipdata = of_device_get_match_data(&pdev->dev);
1308	if (chipdata) {
1309		info = sh_msiof_spi_parse_dt(&pdev->dev);
 
 
 
 
 
 
 
 
 
 
 
 
1310	} else {
1311		chipdata = (const void *)pdev->id_entry->driver_data;
1312		info = dev_get_platdata(&pdev->dev);
1313	}
1314
1315	if (!info) {
1316		dev_err(&pdev->dev, "failed to obtain device info\n");
1317		return -ENXIO;
 
1318	}
1319
1320	if (info->mode == MSIOF_SPI_SLAVE)
1321		ctlr = spi_alloc_slave(&pdev->dev,
1322				       sizeof(struct sh_msiof_spi_priv));
1323	else
1324		ctlr = spi_alloc_master(&pdev->dev,
1325					sizeof(struct sh_msiof_spi_priv));
1326	if (ctlr == NULL)
1327		return -ENOMEM;
1328
1329	p = spi_controller_get_devdata(ctlr);
1330
1331	platform_set_drvdata(pdev, p);
1332	p->ctlr = ctlr;
1333	p->info = info;
1334	p->min_div_pow = chipdata->min_div_pow;
1335
1336	init_completion(&p->done);
1337	init_completion(&p->done_txdma);
1338
1339	p->clk = devm_clk_get(&pdev->dev, NULL);
1340	if (IS_ERR(p->clk)) {
1341		dev_err(&pdev->dev, "cannot get clock\n");
1342		ret = PTR_ERR(p->clk);
1343		goto err1;
1344	}
1345
1346	i = platform_get_irq(pdev, 0);
1347	if (i < 0) {
1348		ret = i;
 
1349		goto err1;
1350	}
1351
1352	p->mapbase = devm_platform_ioremap_resource(pdev, 0);
 
1353	if (IS_ERR(p->mapbase)) {
1354		ret = PTR_ERR(p->mapbase);
1355		goto err1;
1356	}
1357
1358	ret = devm_request_irq(&pdev->dev, i, sh_msiof_spi_irq, 0,
1359			       dev_name(&pdev->dev), p);
1360	if (ret) {
1361		dev_err(&pdev->dev, "unable to request irq\n");
1362		goto err1;
1363	}
1364
1365	p->pdev = pdev;
1366	pm_runtime_enable(&pdev->dev);
1367
1368	/* Platform data may override FIFO sizes */
1369	p->tx_fifo_size = chipdata->tx_fifo_size;
1370	p->rx_fifo_size = chipdata->rx_fifo_size;
1371	if (p->info->tx_fifo_override)
1372		p->tx_fifo_size = p->info->tx_fifo_override;
1373	if (p->info->rx_fifo_override)
1374		p->rx_fifo_size = p->info->rx_fifo_override;
1375
1376	/* Setup GPIO chip selects */
1377	ctlr->num_chipselect = p->info->num_chipselect;
1378	ret = sh_msiof_get_cs_gpios(p);
1379	if (ret)
1380		goto err1;
1381
1382	/* init controller code */
1383	ctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1384	ctlr->mode_bits |= SPI_LSB_FIRST | SPI_3WIRE;
1385	ctlr->flags = chipdata->ctlr_flags;
1386	ctlr->bus_num = pdev->id;
1387	ctlr->dev.of_node = pdev->dev.of_node;
1388	ctlr->setup = sh_msiof_spi_setup;
1389	ctlr->prepare_message = sh_msiof_prepare_message;
1390	ctlr->slave_abort = sh_msiof_slave_abort;
1391	ctlr->bits_per_word_mask = chipdata->bits_per_word_mask;
1392	ctlr->auto_runtime_pm = true;
1393	ctlr->transfer_one = sh_msiof_transfer_one;
1394	ctlr->use_gpio_descriptors = true;
1395
1396	ret = sh_msiof_request_dma(p);
1397	if (ret < 0)
1398		dev_warn(&pdev->dev, "DMA not available, using PIO\n");
1399
1400	ret = devm_spi_register_controller(&pdev->dev, ctlr);
1401	if (ret < 0) {
1402		dev_err(&pdev->dev, "devm_spi_register_controller error.\n");
1403		goto err2;
1404	}
1405
1406	return 0;
1407
1408 err2:
1409	sh_msiof_release_dma(p);
1410	pm_runtime_disable(&pdev->dev);
1411 err1:
1412	spi_controller_put(ctlr);
1413	return ret;
1414}
1415
1416static int sh_msiof_spi_remove(struct platform_device *pdev)
1417{
1418	struct sh_msiof_spi_priv *p = platform_get_drvdata(pdev);
1419
1420	sh_msiof_release_dma(p);
1421	pm_runtime_disable(&pdev->dev);
1422	return 0;
1423}
1424
1425static const struct platform_device_id spi_driver_ids[] = {
1426	{ "spi_sh_msiof",	(kernel_ulong_t)&sh_data },
1427	{},
1428};
1429MODULE_DEVICE_TABLE(platform, spi_driver_ids);
1430
1431#ifdef CONFIG_PM_SLEEP
1432static int sh_msiof_spi_suspend(struct device *dev)
1433{
1434	struct sh_msiof_spi_priv *p = dev_get_drvdata(dev);
1435
1436	return spi_controller_suspend(p->ctlr);
1437}
1438
1439static int sh_msiof_spi_resume(struct device *dev)
1440{
1441	struct sh_msiof_spi_priv *p = dev_get_drvdata(dev);
1442
1443	return spi_controller_resume(p->ctlr);
1444}
1445
1446static SIMPLE_DEV_PM_OPS(sh_msiof_spi_pm_ops, sh_msiof_spi_suspend,
1447			 sh_msiof_spi_resume);
1448#define DEV_PM_OPS	&sh_msiof_spi_pm_ops
1449#else
1450#define DEV_PM_OPS	NULL
1451#endif /* CONFIG_PM_SLEEP */
1452
1453static struct platform_driver sh_msiof_spi_drv = {
1454	.probe		= sh_msiof_spi_probe,
1455	.remove		= sh_msiof_spi_remove,
1456	.id_table	= spi_driver_ids,
1457	.driver		= {
1458		.name		= "spi_sh_msiof",
1459		.pm		= DEV_PM_OPS,
1460		.of_match_table = of_match_ptr(sh_msiof_match),
1461	},
1462};
1463module_platform_driver(sh_msiof_spi_drv);
1464
1465MODULE_DESCRIPTION("SuperH MSIOF SPI Controller Interface Driver");
1466MODULE_AUTHOR("Magnus Damm");
1467MODULE_LICENSE("GPL v2");
1468MODULE_ALIAS("platform:spi_sh_msiof");
v4.10.11
 
   1/*
   2 * SuperH MSIOF SPI Master Interface
   3 *
   4 * Copyright (c) 2009 Magnus Damm
   5 * Copyright (C) 2014 Glider bvba
   6 *
   7 * This program is free software; you can redistribute it and/or modify
   8 * it under the terms of the GNU General Public License version 2 as
   9 * published by the Free Software Foundation.
  10 *
  11 */
  12
  13#include <linux/bitmap.h>
  14#include <linux/clk.h>
  15#include <linux/completion.h>
  16#include <linux/delay.h>
  17#include <linux/dma-mapping.h>
  18#include <linux/dmaengine.h>
  19#include <linux/err.h>
  20#include <linux/gpio.h>
 
  21#include <linux/interrupt.h>
  22#include <linux/io.h>
 
  23#include <linux/kernel.h>
  24#include <linux/module.h>
  25#include <linux/of.h>
  26#include <linux/of_device.h>
  27#include <linux/platform_device.h>
  28#include <linux/pm_runtime.h>
  29#include <linux/sh_dma.h>
  30
  31#include <linux/spi/sh_msiof.h>
  32#include <linux/spi/spi.h>
  33
  34#include <asm/unaligned.h>
  35
  36
  37struct sh_msiof_chipdata {
 
  38	u16 tx_fifo_size;
  39	u16 rx_fifo_size;
  40	u16 master_flags;
 
  41};
  42
  43struct sh_msiof_spi_priv {
  44	struct spi_master *master;
  45	void __iomem *mapbase;
  46	struct clk *clk;
  47	struct platform_device *pdev;
  48	struct sh_msiof_spi_info *info;
  49	struct completion done;
 
  50	unsigned int tx_fifo_size;
  51	unsigned int rx_fifo_size;
 
  52	void *tx_dma_page;
  53	void *rx_dma_page;
  54	dma_addr_t tx_dma_addr;
  55	dma_addr_t rx_dma_addr;
 
 
 
 
  56};
  57
 
 
  58#define TMDR1	0x00	/* Transmit Mode Register 1 */
  59#define TMDR2	0x04	/* Transmit Mode Register 2 */
  60#define TMDR3	0x08	/* Transmit Mode Register 3 */
  61#define RMDR1	0x10	/* Receive Mode Register 1 */
  62#define RMDR2	0x14	/* Receive Mode Register 2 */
  63#define RMDR3	0x18	/* Receive Mode Register 3 */
  64#define TSCR	0x20	/* Transmit Clock Select Register */
  65#define RSCR	0x22	/* Receive Clock Select Register (SH, A1, APE6) */
  66#define CTR	0x28	/* Control Register */
  67#define FCTR	0x30	/* FIFO Control Register */
  68#define STR	0x40	/* Status Register */
  69#define IER	0x44	/* Interrupt Enable Register */
  70#define TDR1	0x48	/* Transmit Control Data Register 1 (SH, A1) */
  71#define TDR2	0x4c	/* Transmit Control Data Register 2 (SH, A1) */
  72#define TFDR	0x50	/* Transmit FIFO Data Register */
  73#define RDR1	0x58	/* Receive Control Data Register 1 (SH, A1) */
  74#define RDR2	0x5c	/* Receive Control Data Register 2 (SH, A1) */
  75#define RFDR	0x60	/* Receive FIFO Data Register */
  76
  77/* TMDR1 and RMDR1 */
  78#define MDR1_TRMD	 0x80000000 /* Transfer Mode (1 = Master mode) */
  79#define MDR1_SYNCMD_MASK 0x30000000 /* SYNC Mode */
  80#define MDR1_SYNCMD_SPI	 0x20000000 /*   Level mode/SPI */
  81#define MDR1_SYNCMD_LR	 0x30000000 /*   L/R mode */
  82#define MDR1_SYNCAC_SHIFT	 25 /* Sync Polarity (1 = Active-low) */
  83#define MDR1_BITLSB_SHIFT	 24 /* MSB/LSB First (1 = LSB first) */
  84#define MDR1_DTDL_SHIFT		 20 /* Data Pin Bit Delay for MSIOF_SYNC */
  85#define MDR1_SYNCDL_SHIFT	 16 /* Frame Sync Signal Timing Delay */
  86#define MDR1_FLD_MASK	 0x0000000c /* Frame Sync Signal Interval (0-3) */
  87#define MDR1_FLD_SHIFT		  2
  88#define MDR1_XXSTP	 0x00000001 /* Transmission/Reception Stop on FIFO */
  89/* TMDR1 */
  90#define TMDR1_PCON	 0x40000000 /* Transfer Signal Connection */
 
 
  91
  92/* TMDR2 and RMDR2 */
  93#define MDR2_BITLEN1(i)	(((i) - 1) << 24) /* Data Size (8-32 bits) */
  94#define MDR2_WDLEN1(i)	(((i) - 1) << 16) /* Word Count (1-64/256 (SH, A1))) */
  95#define MDR2_GRPMASK1	0x00000001 /* Group Output Mask 1 (SH, A1) */
  96
  97/* TSCR and RSCR */
  98#define SCR_BRPS_MASK	    0x1f00 /* Prescaler Setting (1-32) */
  99#define SCR_BRPS(i)	(((i) - 1) << 8)
 100#define SCR_BRDV_MASK	    0x0007 /* Baud Rate Generator's Division Ratio */
 101#define SCR_BRDV_DIV_2	    0x0000
 102#define SCR_BRDV_DIV_4	    0x0001
 103#define SCR_BRDV_DIV_8	    0x0002
 104#define SCR_BRDV_DIV_16	    0x0003
 105#define SCR_BRDV_DIV_32	    0x0004
 106#define SCR_BRDV_DIV_1	    0x0007
 107
 108/* CTR */
 109#define CTR_TSCKIZ_MASK	0xc0000000 /* Transmit Clock I/O Polarity Select */
 110#define CTR_TSCKIZ_SCK	0x80000000 /*   Disable SCK when TX disabled */
 111#define CTR_TSCKIZ_POL_SHIFT	30 /*   Transmit Clock Polarity */
 112#define CTR_RSCKIZ_MASK	0x30000000 /* Receive Clock Polarity Select */
 113#define CTR_RSCKIZ_SCK	0x20000000 /*   Must match CTR_TSCKIZ_SCK */
 114#define CTR_RSCKIZ_POL_SHIFT	28 /*   Receive Clock Polarity */
 115#define CTR_TEDG_SHIFT		27 /* Transmit Timing (1 = falling edge) */
 116#define CTR_REDG_SHIFT		26 /* Receive Timing (1 = falling edge) */
 117#define CTR_TXDIZ_MASK	0x00c00000 /* Pin Output When TX is Disabled */
 118#define CTR_TXDIZ_LOW	0x00000000 /*   0 */
 119#define CTR_TXDIZ_HIGH	0x00400000 /*   1 */
 120#define CTR_TXDIZ_HIZ	0x00800000 /*   High-impedance */
 121#define CTR_TSCKE	0x00008000 /* Transmit Serial Clock Output Enable */
 122#define CTR_TFSE	0x00004000 /* Transmit Frame Sync Signal Output Enable */
 123#define CTR_TXE		0x00000200 /* Transmit Enable */
 124#define CTR_RXE		0x00000100 /* Receive Enable */
 
 
 125
 126/* FCTR */
 127#define FCTR_TFWM_MASK	0xe0000000 /* Transmit FIFO Watermark */
 128#define FCTR_TFWM_64	0x00000000 /*  Transfer Request when 64 empty stages */
 129#define FCTR_TFWM_32	0x20000000 /*  Transfer Request when 32 empty stages */
 130#define FCTR_TFWM_24	0x40000000 /*  Transfer Request when 24 empty stages */
 131#define FCTR_TFWM_16	0x60000000 /*  Transfer Request when 16 empty stages */
 132#define FCTR_TFWM_12	0x80000000 /*  Transfer Request when 12 empty stages */
 133#define FCTR_TFWM_8	0xa0000000 /*  Transfer Request when 8 empty stages */
 134#define FCTR_TFWM_4	0xc0000000 /*  Transfer Request when 4 empty stages */
 135#define FCTR_TFWM_1	0xe0000000 /*  Transfer Request when 1 empty stage */
 136#define FCTR_TFUA_MASK	0x07f00000 /* Transmit FIFO Usable Area */
 137#define FCTR_TFUA_SHIFT		20
 138#define FCTR_TFUA(i)	((i) << FCTR_TFUA_SHIFT)
 139#define FCTR_RFWM_MASK	0x0000e000 /* Receive FIFO Watermark */
 140#define FCTR_RFWM_1	0x00000000 /*  Transfer Request when 1 valid stages */
 141#define FCTR_RFWM_4	0x00002000 /*  Transfer Request when 4 valid stages */
 142#define FCTR_RFWM_8	0x00004000 /*  Transfer Request when 8 valid stages */
 143#define FCTR_RFWM_16	0x00006000 /*  Transfer Request when 16 valid stages */
 144#define FCTR_RFWM_32	0x00008000 /*  Transfer Request when 32 valid stages */
 145#define FCTR_RFWM_64	0x0000a000 /*  Transfer Request when 64 valid stages */
 146#define FCTR_RFWM_128	0x0000c000 /*  Transfer Request when 128 valid stages */
 147#define FCTR_RFWM_256	0x0000e000 /*  Transfer Request when 256 valid stages */
 148#define FCTR_RFUA_MASK	0x00001ff0 /* Receive FIFO Usable Area (0x40 = full) */
 149#define FCTR_RFUA_SHIFT		 4
 150#define FCTR_RFUA(i)	((i) << FCTR_RFUA_SHIFT)
 151
 152/* STR */
 153#define STR_TFEMP	0x20000000 /* Transmit FIFO Empty */
 154#define STR_TDREQ	0x10000000 /* Transmit Data Transfer Request */
 155#define STR_TEOF	0x00800000 /* Frame Transmission End */
 156#define STR_TFSERR	0x00200000 /* Transmit Frame Synchronization Error */
 157#define STR_TFOVF	0x00100000 /* Transmit FIFO Overflow */
 158#define STR_TFUDF	0x00080000 /* Transmit FIFO Underflow */
 159#define STR_RFFUL	0x00002000 /* Receive FIFO Full */
 160#define STR_RDREQ	0x00001000 /* Receive Data Transfer Request */
 161#define STR_REOF	0x00000080 /* Frame Reception End */
 162#define STR_RFSERR	0x00000020 /* Receive Frame Synchronization Error */
 163#define STR_RFUDF	0x00000010 /* Receive FIFO Underflow */
 164#define STR_RFOVF	0x00000008 /* Receive FIFO Overflow */
 165
 166/* IER */
 167#define IER_TDMAE	0x80000000 /* Transmit Data DMA Transfer Req. Enable */
 168#define IER_TFEMPE	0x20000000 /* Transmit FIFO Empty Enable */
 169#define IER_TDREQE	0x10000000 /* Transmit Data Transfer Request Enable */
 170#define IER_TEOFE	0x00800000 /* Frame Transmission End Enable */
 171#define IER_TFSERRE	0x00200000 /* Transmit Frame Sync Error Enable */
 172#define IER_TFOVFE	0x00100000 /* Transmit FIFO Overflow Enable */
 173#define IER_TFUDFE	0x00080000 /* Transmit FIFO Underflow Enable */
 174#define IER_RDMAE	0x00008000 /* Receive Data DMA Transfer Req. Enable */
 175#define IER_RFFULE	0x00002000 /* Receive FIFO Full Enable */
 176#define IER_RDREQE	0x00001000 /* Receive Data Transfer Request Enable */
 177#define IER_REOFE	0x00000080 /* Frame Reception End Enable */
 178#define IER_RFSERRE	0x00000020 /* Receive Frame Sync Error Enable */
 179#define IER_RFUDFE	0x00000010 /* Receive FIFO Underflow Enable */
 180#define IER_RFOVFE	0x00000008 /* Receive FIFO Overflow Enable */
 181
 182
 183static u32 sh_msiof_read(struct sh_msiof_spi_priv *p, int reg_offs)
 184{
 185	switch (reg_offs) {
 186	case TSCR:
 187	case RSCR:
 188		return ioread16(p->mapbase + reg_offs);
 189	default:
 190		return ioread32(p->mapbase + reg_offs);
 191	}
 192}
 193
 194static void sh_msiof_write(struct sh_msiof_spi_priv *p, int reg_offs,
 195			   u32 value)
 196{
 197	switch (reg_offs) {
 198	case TSCR:
 199	case RSCR:
 200		iowrite16(value, p->mapbase + reg_offs);
 201		break;
 202	default:
 203		iowrite32(value, p->mapbase + reg_offs);
 204		break;
 205	}
 206}
 207
 208static int sh_msiof_modify_ctr_wait(struct sh_msiof_spi_priv *p,
 209				    u32 clr, u32 set)
 210{
 211	u32 mask = clr | set;
 212	u32 data;
 213	int k;
 214
 215	data = sh_msiof_read(p, CTR);
 216	data &= ~clr;
 217	data |= set;
 218	sh_msiof_write(p, CTR, data);
 219
 220	for (k = 100; k > 0; k--) {
 221		if ((sh_msiof_read(p, CTR) & mask) == set)
 222			break;
 223
 224		udelay(10);
 225	}
 226
 227	return k > 0 ? 0 : -ETIMEDOUT;
 228}
 229
 230static irqreturn_t sh_msiof_spi_irq(int irq, void *data)
 231{
 232	struct sh_msiof_spi_priv *p = data;
 233
 234	/* just disable the interrupt and wake up */
 235	sh_msiof_write(p, IER, 0);
 236	complete(&p->done);
 237
 238	return IRQ_HANDLED;
 239}
 240
 241static struct {
 242	unsigned short div;
 243	unsigned short brdv;
 244} const sh_msiof_spi_div_table[] = {
 245	{ 1,	SCR_BRDV_DIV_1 },
 246	{ 2,	SCR_BRDV_DIV_2 },
 247	{ 4,	SCR_BRDV_DIV_4 },
 248	{ 8,	SCR_BRDV_DIV_8 },
 249	{ 16,	SCR_BRDV_DIV_16 },
 250	{ 32,	SCR_BRDV_DIV_32 },
 
 
 
 
 
 
 251};
 252
 253static void sh_msiof_spi_set_clk_regs(struct sh_msiof_spi_priv *p,
 254				      unsigned long parent_rate, u32 spi_hz)
 255{
 256	unsigned long div = 1024;
 257	u32 brps, scr;
 258	size_t k;
 259
 260	if (!WARN_ON(!spi_hz || !parent_rate))
 261		div = DIV_ROUND_UP(parent_rate, spi_hz);
 
 
 
 262
 263	for (k = 0; k < ARRAY_SIZE(sh_msiof_spi_div_table); k++) {
 264		brps = DIV_ROUND_UP(div, sh_msiof_spi_div_table[k].div);
 265		/* SCR_BRDV_DIV_1 is valid only if BRPS is x 1/1 or x 1/2 */
 266		if (sh_msiof_spi_div_table[k].div == 1 && brps > 2)
 267			continue;
 268		if (brps <= 32) /* max of brdv is 32 */
 269			break;
 
 
 
 
 
 
 
 
 
 
 
 
 270	}
 271
 272	k = min_t(int, k, ARRAY_SIZE(sh_msiof_spi_div_table) - 1);
 273
 274	scr = sh_msiof_spi_div_table[k].brdv | SCR_BRPS(brps);
 275	sh_msiof_write(p, TSCR, scr);
 276	if (!(p->master->flags & SPI_MASTER_MUST_TX))
 277		sh_msiof_write(p, RSCR, scr);
 278}
 279
 280static u32 sh_msiof_get_delay_bit(u32 dtdl_or_syncdl)
 281{
 282	/*
 283	 * DTDL/SYNCDL bit	: p->info->dtdl or p->info->syncdl
 284	 * b'000		: 0
 285	 * b'001		: 100
 286	 * b'010		: 200
 287	 * b'011 (SYNCDL only)	: 300
 288	 * b'101		: 50
 289	 * b'110		: 150
 290	 */
 291	if (dtdl_or_syncdl % 100)
 292		return dtdl_or_syncdl / 100 + 5;
 293	else
 294		return dtdl_or_syncdl / 100;
 295}
 296
 297static u32 sh_msiof_spi_get_dtdl_and_syncdl(struct sh_msiof_spi_priv *p)
 298{
 299	u32 val;
 300
 301	if (!p->info)
 302		return 0;
 303
 304	/* check if DTDL and SYNCDL is allowed value */
 305	if (p->info->dtdl > 200 || p->info->syncdl > 300) {
 306		dev_warn(&p->pdev->dev, "DTDL or SYNCDL is too large\n");
 307		return 0;
 308	}
 309
 310	/* check if the sum of DTDL and SYNCDL becomes an integer value  */
 311	if ((p->info->dtdl + p->info->syncdl) % 100) {
 312		dev_warn(&p->pdev->dev, "the sum of DTDL/SYNCDL is not good\n");
 313		return 0;
 314	}
 315
 316	val = sh_msiof_get_delay_bit(p->info->dtdl) << MDR1_DTDL_SHIFT;
 317	val |= sh_msiof_get_delay_bit(p->info->syncdl) << MDR1_SYNCDL_SHIFT;
 318
 319	return val;
 320}
 321
 322static void sh_msiof_spi_set_pin_regs(struct sh_msiof_spi_priv *p,
 323				      u32 cpol, u32 cpha,
 324				      u32 tx_hi_z, u32 lsb_first, u32 cs_high)
 325{
 326	u32 tmp;
 327	int edge;
 328
 329	/*
 330	 * CPOL CPHA     TSCKIZ RSCKIZ TEDG REDG
 331	 *    0    0         10     10    1    1
 332	 *    0    1         10     10    0    0
 333	 *    1    0         11     11    0    0
 334	 *    1    1         11     11    1    1
 335	 */
 336	tmp = MDR1_SYNCMD_SPI | 1 << MDR1_FLD_SHIFT | MDR1_XXSTP;
 337	tmp |= !cs_high << MDR1_SYNCAC_SHIFT;
 338	tmp |= lsb_first << MDR1_BITLSB_SHIFT;
 339	tmp |= sh_msiof_spi_get_dtdl_and_syncdl(p);
 340	sh_msiof_write(p, TMDR1, tmp | MDR1_TRMD | TMDR1_PCON);
 341	if (p->master->flags & SPI_MASTER_MUST_TX) {
 
 
 
 
 
 
 342		/* These bits are reserved if RX needs TX */
 343		tmp &= ~0x0000ffff;
 344	}
 345	sh_msiof_write(p, RMDR1, tmp);
 346
 347	tmp = 0;
 348	tmp |= CTR_TSCKIZ_SCK | cpol << CTR_TSCKIZ_POL_SHIFT;
 349	tmp |= CTR_RSCKIZ_SCK | cpol << CTR_RSCKIZ_POL_SHIFT;
 350
 351	edge = cpol ^ !cpha;
 352
 353	tmp |= edge << CTR_TEDG_SHIFT;
 354	tmp |= edge << CTR_REDG_SHIFT;
 355	tmp |= tx_hi_z ? CTR_TXDIZ_HIZ : CTR_TXDIZ_LOW;
 356	sh_msiof_write(p, CTR, tmp);
 357}
 358
 359static void sh_msiof_spi_set_mode_regs(struct sh_msiof_spi_priv *p,
 360				       const void *tx_buf, void *rx_buf,
 361				       u32 bits, u32 words)
 362{
 363	u32 dr2 = MDR2_BITLEN1(bits) | MDR2_WDLEN1(words);
 364
 365	if (tx_buf || (p->master->flags & SPI_MASTER_MUST_TX))
 366		sh_msiof_write(p, TMDR2, dr2);
 367	else
 368		sh_msiof_write(p, TMDR2, dr2 | MDR2_GRPMASK1);
 369
 370	if (rx_buf)
 371		sh_msiof_write(p, RMDR2, dr2);
 372}
 373
 374static void sh_msiof_reset_str(struct sh_msiof_spi_priv *p)
 375{
 376	sh_msiof_write(p, STR, sh_msiof_read(p, STR));
 
 377}
 378
 379static void sh_msiof_spi_write_fifo_8(struct sh_msiof_spi_priv *p,
 380				      const void *tx_buf, int words, int fs)
 381{
 382	const u8 *buf_8 = tx_buf;
 383	int k;
 384
 385	for (k = 0; k < words; k++)
 386		sh_msiof_write(p, TFDR, buf_8[k] << fs);
 387}
 388
 389static void sh_msiof_spi_write_fifo_16(struct sh_msiof_spi_priv *p,
 390				       const void *tx_buf, int words, int fs)
 391{
 392	const u16 *buf_16 = tx_buf;
 393	int k;
 394
 395	for (k = 0; k < words; k++)
 396		sh_msiof_write(p, TFDR, buf_16[k] << fs);
 397}
 398
 399static void sh_msiof_spi_write_fifo_16u(struct sh_msiof_spi_priv *p,
 400					const void *tx_buf, int words, int fs)
 401{
 402	const u16 *buf_16 = tx_buf;
 403	int k;
 404
 405	for (k = 0; k < words; k++)
 406		sh_msiof_write(p, TFDR, get_unaligned(&buf_16[k]) << fs);
 407}
 408
 409static void sh_msiof_spi_write_fifo_32(struct sh_msiof_spi_priv *p,
 410				       const void *tx_buf, int words, int fs)
 411{
 412	const u32 *buf_32 = tx_buf;
 413	int k;
 414
 415	for (k = 0; k < words; k++)
 416		sh_msiof_write(p, TFDR, buf_32[k] << fs);
 417}
 418
 419static void sh_msiof_spi_write_fifo_32u(struct sh_msiof_spi_priv *p,
 420					const void *tx_buf, int words, int fs)
 421{
 422	const u32 *buf_32 = tx_buf;
 423	int k;
 424
 425	for (k = 0; k < words; k++)
 426		sh_msiof_write(p, TFDR, get_unaligned(&buf_32[k]) << fs);
 427}
 428
 429static void sh_msiof_spi_write_fifo_s32(struct sh_msiof_spi_priv *p,
 430					const void *tx_buf, int words, int fs)
 431{
 432	const u32 *buf_32 = tx_buf;
 433	int k;
 434
 435	for (k = 0; k < words; k++)
 436		sh_msiof_write(p, TFDR, swab32(buf_32[k] << fs));
 437}
 438
 439static void sh_msiof_spi_write_fifo_s32u(struct sh_msiof_spi_priv *p,
 440					 const void *tx_buf, int words, int fs)
 441{
 442	const u32 *buf_32 = tx_buf;
 443	int k;
 444
 445	for (k = 0; k < words; k++)
 446		sh_msiof_write(p, TFDR, swab32(get_unaligned(&buf_32[k]) << fs));
 447}
 448
 449static void sh_msiof_spi_read_fifo_8(struct sh_msiof_spi_priv *p,
 450				     void *rx_buf, int words, int fs)
 451{
 452	u8 *buf_8 = rx_buf;
 453	int k;
 454
 455	for (k = 0; k < words; k++)
 456		buf_8[k] = sh_msiof_read(p, RFDR) >> fs;
 457}
 458
 459static void sh_msiof_spi_read_fifo_16(struct sh_msiof_spi_priv *p,
 460				      void *rx_buf, int words, int fs)
 461{
 462	u16 *buf_16 = rx_buf;
 463	int k;
 464
 465	for (k = 0; k < words; k++)
 466		buf_16[k] = sh_msiof_read(p, RFDR) >> fs;
 467}
 468
 469static void sh_msiof_spi_read_fifo_16u(struct sh_msiof_spi_priv *p,
 470				       void *rx_buf, int words, int fs)
 471{
 472	u16 *buf_16 = rx_buf;
 473	int k;
 474
 475	for (k = 0; k < words; k++)
 476		put_unaligned(sh_msiof_read(p, RFDR) >> fs, &buf_16[k]);
 477}
 478
 479static void sh_msiof_spi_read_fifo_32(struct sh_msiof_spi_priv *p,
 480				      void *rx_buf, int words, int fs)
 481{
 482	u32 *buf_32 = rx_buf;
 483	int k;
 484
 485	for (k = 0; k < words; k++)
 486		buf_32[k] = sh_msiof_read(p, RFDR) >> fs;
 487}
 488
 489static void sh_msiof_spi_read_fifo_32u(struct sh_msiof_spi_priv *p,
 490				       void *rx_buf, int words, int fs)
 491{
 492	u32 *buf_32 = rx_buf;
 493	int k;
 494
 495	for (k = 0; k < words; k++)
 496		put_unaligned(sh_msiof_read(p, RFDR) >> fs, &buf_32[k]);
 497}
 498
 499static void sh_msiof_spi_read_fifo_s32(struct sh_msiof_spi_priv *p,
 500				       void *rx_buf, int words, int fs)
 501{
 502	u32 *buf_32 = rx_buf;
 503	int k;
 504
 505	for (k = 0; k < words; k++)
 506		buf_32[k] = swab32(sh_msiof_read(p, RFDR) >> fs);
 507}
 508
 509static void sh_msiof_spi_read_fifo_s32u(struct sh_msiof_spi_priv *p,
 510				       void *rx_buf, int words, int fs)
 511{
 512	u32 *buf_32 = rx_buf;
 513	int k;
 514
 515	for (k = 0; k < words; k++)
 516		put_unaligned(swab32(sh_msiof_read(p, RFDR) >> fs), &buf_32[k]);
 517}
 518
 519static int sh_msiof_spi_setup(struct spi_device *spi)
 520{
 521	struct device_node	*np = spi->master->dev.of_node;
 522	struct sh_msiof_spi_priv *p = spi_master_get_devdata(spi->master);
 
 523
 524	pm_runtime_get_sync(&p->pdev->dev);
 525
 526	if (!np) {
 527		/*
 528		 * Use spi->controller_data for CS (same strategy as spi_gpio),
 529		 * if any. otherwise let HW control CS
 530		 */
 531		spi->cs_gpio = (uintptr_t)spi->controller_data;
 532	}
 533
 534	/* Configure pins before deasserting CS */
 535	sh_msiof_spi_set_pin_regs(p, !!(spi->mode & SPI_CPOL),
 536				  !!(spi->mode & SPI_CPHA),
 537				  !!(spi->mode & SPI_3WIRE),
 538				  !!(spi->mode & SPI_LSB_FIRST),
 539				  !!(spi->mode & SPI_CS_HIGH));
 540
 541	if (spi->cs_gpio >= 0)
 542		gpio_set_value(spi->cs_gpio, !(spi->mode & SPI_CS_HIGH));
 543
 
 
 
 544
 
 
 
 
 
 
 
 
 
 
 
 
 545	pm_runtime_put(&p->pdev->dev);
 546
 
 547	return 0;
 548}
 549
 550static int sh_msiof_prepare_message(struct spi_master *master,
 551				    struct spi_message *msg)
 552{
 553	struct sh_msiof_spi_priv *p = spi_master_get_devdata(master);
 554	const struct spi_device *spi = msg->spi;
 
 555
 556	/* Configure pins before asserting CS */
 557	sh_msiof_spi_set_pin_regs(p, !!(spi->mode & SPI_CPOL),
 
 
 
 
 
 
 
 558				  !!(spi->mode & SPI_CPHA),
 559				  !!(spi->mode & SPI_3WIRE),
 560				  !!(spi->mode & SPI_LSB_FIRST),
 561				  !!(spi->mode & SPI_CS_HIGH));
 562	return 0;
 563}
 564
 565static int sh_msiof_spi_start(struct sh_msiof_spi_priv *p, void *rx_buf)
 566{
 567	int ret;
 
 568
 569	/* setup clock and rx/tx signals */
 570	ret = sh_msiof_modify_ctr_wait(p, 0, CTR_TSCKE);
 
 571	if (rx_buf && !ret)
 572		ret = sh_msiof_modify_ctr_wait(p, 0, CTR_RXE);
 573	if (!ret)
 574		ret = sh_msiof_modify_ctr_wait(p, 0, CTR_TXE);
 575
 576	/* start by setting frame bit */
 577	if (!ret)
 578		ret = sh_msiof_modify_ctr_wait(p, 0, CTR_TFSE);
 579
 580	return ret;
 581}
 582
 583static int sh_msiof_spi_stop(struct sh_msiof_spi_priv *p, void *rx_buf)
 584{
 585	int ret;
 
 586
 587	/* shut down frame, rx/tx and clock signals */
 588	ret = sh_msiof_modify_ctr_wait(p, CTR_TFSE, 0);
 
 589	if (!ret)
 590		ret = sh_msiof_modify_ctr_wait(p, CTR_TXE, 0);
 591	if (rx_buf && !ret)
 592		ret = sh_msiof_modify_ctr_wait(p, CTR_RXE, 0);
 593	if (!ret)
 594		ret = sh_msiof_modify_ctr_wait(p, CTR_TSCKE, 0);
 595
 596	return ret;
 597}
 598
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 599static int sh_msiof_spi_txrx_once(struct sh_msiof_spi_priv *p,
 600				  void (*tx_fifo)(struct sh_msiof_spi_priv *,
 601						  const void *, int, int),
 602				  void (*rx_fifo)(struct sh_msiof_spi_priv *,
 603						  void *, int, int),
 604				  const void *tx_buf, void *rx_buf,
 605				  int words, int bits)
 606{
 607	int fifo_shift;
 608	int ret;
 609
 610	/* limit maximum word transfer to rx/tx fifo size */
 611	if (tx_buf)
 612		words = min_t(int, words, p->tx_fifo_size);
 613	if (rx_buf)
 614		words = min_t(int, words, p->rx_fifo_size);
 615
 616	/* the fifo contents need shifting */
 617	fifo_shift = 32 - bits;
 618
 619	/* default FIFO watermarks for PIO */
 620	sh_msiof_write(p, FCTR, 0);
 621
 622	/* setup msiof transfer mode registers */
 623	sh_msiof_spi_set_mode_regs(p, tx_buf, rx_buf, bits, words);
 624	sh_msiof_write(p, IER, IER_TEOFE | IER_REOFE);
 625
 626	/* write tx fifo */
 627	if (tx_buf)
 628		tx_fifo(p, tx_buf, words, fifo_shift);
 629
 630	reinit_completion(&p->done);
 
 631
 632	ret = sh_msiof_spi_start(p, rx_buf);
 633	if (ret) {
 634		dev_err(&p->pdev->dev, "failed to start hardware\n");
 635		goto stop_ier;
 636	}
 637
 638	/* wait for tx fifo to be emptied / rx fifo to be filled */
 639	if (!wait_for_completion_timeout(&p->done, HZ)) {
 640		dev_err(&p->pdev->dev, "PIO timeout\n");
 641		ret = -ETIMEDOUT;
 642		goto stop_reset;
 643	}
 644
 645	/* read rx fifo */
 646	if (rx_buf)
 647		rx_fifo(p, rx_buf, words, fifo_shift);
 648
 649	/* clear status bits */
 650	sh_msiof_reset_str(p);
 651
 652	ret = sh_msiof_spi_stop(p, rx_buf);
 653	if (ret) {
 654		dev_err(&p->pdev->dev, "failed to shut down hardware\n");
 655		return ret;
 656	}
 657
 658	return words;
 659
 660stop_reset:
 661	sh_msiof_reset_str(p);
 662	sh_msiof_spi_stop(p, rx_buf);
 663stop_ier:
 664	sh_msiof_write(p, IER, 0);
 665	return ret;
 666}
 667
 668static void sh_msiof_dma_complete(void *arg)
 669{
 670	struct sh_msiof_spi_priv *p = arg;
 671
 672	sh_msiof_write(p, IER, 0);
 673	complete(&p->done);
 674}
 675
 676static int sh_msiof_dma_once(struct sh_msiof_spi_priv *p, const void *tx,
 677			     void *rx, unsigned int len)
 678{
 679	u32 ier_bits = 0;
 680	struct dma_async_tx_descriptor *desc_tx = NULL, *desc_rx = NULL;
 681	dma_cookie_t cookie;
 682	int ret;
 683
 684	/* First prepare and submit the DMA request(s), as this may fail */
 685	if (rx) {
 686		ier_bits |= IER_RDREQE | IER_RDMAE;
 687		desc_rx = dmaengine_prep_slave_single(p->master->dma_rx,
 688					p->rx_dma_addr, len, DMA_FROM_DEVICE,
 689					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 690		if (!desc_rx)
 691			return -EAGAIN;
 692
 693		desc_rx->callback = sh_msiof_dma_complete;
 694		desc_rx->callback_param = p;
 695		cookie = dmaengine_submit(desc_rx);
 696		if (dma_submit_error(cookie))
 697			return cookie;
 698	}
 699
 700	if (tx) {
 701		ier_bits |= IER_TDREQE | IER_TDMAE;
 702		dma_sync_single_for_device(p->master->dma_tx->device->dev,
 703					   p->tx_dma_addr, len, DMA_TO_DEVICE);
 704		desc_tx = dmaengine_prep_slave_single(p->master->dma_tx,
 705					p->tx_dma_addr, len, DMA_TO_DEVICE,
 706					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 707		if (!desc_tx) {
 708			ret = -EAGAIN;
 709			goto no_dma_tx;
 710		}
 711
 712		if (rx) {
 713			/* No callback */
 714			desc_tx->callback = NULL;
 715		} else {
 716			desc_tx->callback = sh_msiof_dma_complete;
 717			desc_tx->callback_param = p;
 718		}
 719		cookie = dmaengine_submit(desc_tx);
 720		if (dma_submit_error(cookie)) {
 721			ret = cookie;
 722			goto no_dma_tx;
 723		}
 724	}
 725
 726	/* 1 stage FIFO watermarks for DMA */
 727	sh_msiof_write(p, FCTR, FCTR_TFWM_1 | FCTR_RFWM_1);
 728
 729	/* setup msiof transfer mode registers (32-bit words) */
 730	sh_msiof_spi_set_mode_regs(p, tx, rx, 32, len / 4);
 731
 732	sh_msiof_write(p, IER, ier_bits);
 733
 734	reinit_completion(&p->done);
 
 
 
 735
 736	/* Now start DMA */
 737	if (rx)
 738		dma_async_issue_pending(p->master->dma_rx);
 739	if (tx)
 740		dma_async_issue_pending(p->master->dma_tx);
 741
 742	ret = sh_msiof_spi_start(p, rx);
 743	if (ret) {
 744		dev_err(&p->pdev->dev, "failed to start hardware\n");
 745		goto stop_dma;
 746	}
 747
 748	/* wait for tx fifo to be emptied / rx fifo to be filled */
 749	if (!wait_for_completion_timeout(&p->done, HZ)) {
 750		dev_err(&p->pdev->dev, "DMA timeout\n");
 751		ret = -ETIMEDOUT;
 752		goto stop_reset;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 753	}
 754
 755	/* clear status bits */
 756	sh_msiof_reset_str(p);
 757
 758	ret = sh_msiof_spi_stop(p, rx);
 759	if (ret) {
 760		dev_err(&p->pdev->dev, "failed to shut down hardware\n");
 761		return ret;
 762	}
 763
 764	if (rx)
 765		dma_sync_single_for_cpu(p->master->dma_rx->device->dev,
 766					p->rx_dma_addr, len,
 767					DMA_FROM_DEVICE);
 768
 769	return 0;
 770
 771stop_reset:
 772	sh_msiof_reset_str(p);
 773	sh_msiof_spi_stop(p, rx);
 774stop_dma:
 775	if (tx)
 776		dmaengine_terminate_all(p->master->dma_tx);
 777no_dma_tx:
 778	if (rx)
 779		dmaengine_terminate_all(p->master->dma_rx);
 780	sh_msiof_write(p, IER, 0);
 781	return ret;
 782}
 783
 784static void copy_bswap32(u32 *dst, const u32 *src, unsigned int words)
 785{
 786	/* src or dst can be unaligned, but not both */
 787	if ((unsigned long)src & 3) {
 788		while (words--) {
 789			*dst++ = swab32(get_unaligned(src));
 790			src++;
 791		}
 792	} else if ((unsigned long)dst & 3) {
 793		while (words--) {
 794			put_unaligned(swab32(*src++), dst);
 795			dst++;
 796		}
 797	} else {
 798		while (words--)
 799			*dst++ = swab32(*src++);
 800	}
 801}
 802
 803static void copy_wswap32(u32 *dst, const u32 *src, unsigned int words)
 804{
 805	/* src or dst can be unaligned, but not both */
 806	if ((unsigned long)src & 3) {
 807		while (words--) {
 808			*dst++ = swahw32(get_unaligned(src));
 809			src++;
 810		}
 811	} else if ((unsigned long)dst & 3) {
 812		while (words--) {
 813			put_unaligned(swahw32(*src++), dst);
 814			dst++;
 815		}
 816	} else {
 817		while (words--)
 818			*dst++ = swahw32(*src++);
 819	}
 820}
 821
 822static void copy_plain32(u32 *dst, const u32 *src, unsigned int words)
 823{
 824	memcpy(dst, src, words * 4);
 825}
 826
 827static int sh_msiof_transfer_one(struct spi_master *master,
 828				 struct spi_device *spi,
 829				 struct spi_transfer *t)
 830{
 831	struct sh_msiof_spi_priv *p = spi_master_get_devdata(master);
 832	void (*copy32)(u32 *, const u32 *, unsigned int);
 833	void (*tx_fifo)(struct sh_msiof_spi_priv *, const void *, int, int);
 834	void (*rx_fifo)(struct sh_msiof_spi_priv *, void *, int, int);
 835	const void *tx_buf = t->tx_buf;
 836	void *rx_buf = t->rx_buf;
 837	unsigned int len = t->len;
 838	unsigned int bits = t->bits_per_word;
 839	unsigned int bytes_per_word;
 840	unsigned int words;
 841	int n;
 842	bool swab;
 843	int ret;
 844
 
 
 
 845	/* setup clocks (clock already enabled in chipselect()) */
 846	sh_msiof_spi_set_clk_regs(p, clk_get_rate(p->clk), t->speed_hz);
 
 847
 848	while (master->dma_tx && len > 15) {
 849		/*
 850		 *  DMA supports 32-bit words only, hence pack 8-bit and 16-bit
 851		 *  words, with byte resp. word swapping.
 852		 */
 853		unsigned int l = 0;
 854
 855		if (tx_buf)
 856			l = min(len, p->tx_fifo_size * 4);
 857		if (rx_buf)
 858			l = min(len, p->rx_fifo_size * 4);
 859
 860		if (bits <= 8) {
 861			if (l & 3)
 862				break;
 863			copy32 = copy_bswap32;
 864		} else if (bits <= 16) {
 865			if (l & 1)
 866				break;
 867			copy32 = copy_wswap32;
 868		} else {
 869			copy32 = copy_plain32;
 870		}
 871
 872		if (tx_buf)
 873			copy32(p->tx_dma_page, tx_buf, l / 4);
 874
 875		ret = sh_msiof_dma_once(p, tx_buf, rx_buf, l);
 876		if (ret == -EAGAIN) {
 877			pr_warn_once("%s %s: DMA not available, falling back to PIO\n",
 878				     dev_driver_string(&p->pdev->dev),
 879				     dev_name(&p->pdev->dev));
 880			break;
 881		}
 882		if (ret)
 883			return ret;
 884
 885		if (rx_buf) {
 886			copy32(rx_buf, p->rx_dma_page, l / 4);
 887			rx_buf += l;
 888		}
 889		if (tx_buf)
 890			tx_buf += l;
 891
 892		len -= l;
 893		if (!len)
 894			return 0;
 895	}
 896
 897	if (bits <= 8 && len > 15 && !(len & 3)) {
 898		bits = 32;
 899		swab = true;
 900	} else {
 901		swab = false;
 902	}
 903
 904	/* setup bytes per word and fifo read/write functions */
 905	if (bits <= 8) {
 906		bytes_per_word = 1;
 907		tx_fifo = sh_msiof_spi_write_fifo_8;
 908		rx_fifo = sh_msiof_spi_read_fifo_8;
 909	} else if (bits <= 16) {
 910		bytes_per_word = 2;
 911		if ((unsigned long)tx_buf & 0x01)
 912			tx_fifo = sh_msiof_spi_write_fifo_16u;
 913		else
 914			tx_fifo = sh_msiof_spi_write_fifo_16;
 915
 916		if ((unsigned long)rx_buf & 0x01)
 917			rx_fifo = sh_msiof_spi_read_fifo_16u;
 918		else
 919			rx_fifo = sh_msiof_spi_read_fifo_16;
 920	} else if (swab) {
 921		bytes_per_word = 4;
 922		if ((unsigned long)tx_buf & 0x03)
 923			tx_fifo = sh_msiof_spi_write_fifo_s32u;
 924		else
 925			tx_fifo = sh_msiof_spi_write_fifo_s32;
 926
 927		if ((unsigned long)rx_buf & 0x03)
 928			rx_fifo = sh_msiof_spi_read_fifo_s32u;
 929		else
 930			rx_fifo = sh_msiof_spi_read_fifo_s32;
 931	} else {
 932		bytes_per_word = 4;
 933		if ((unsigned long)tx_buf & 0x03)
 934			tx_fifo = sh_msiof_spi_write_fifo_32u;
 935		else
 936			tx_fifo = sh_msiof_spi_write_fifo_32;
 937
 938		if ((unsigned long)rx_buf & 0x03)
 939			rx_fifo = sh_msiof_spi_read_fifo_32u;
 940		else
 941			rx_fifo = sh_msiof_spi_read_fifo_32;
 942	}
 943
 944	/* transfer in fifo sized chunks */
 945	words = len / bytes_per_word;
 946
 947	while (words > 0) {
 948		n = sh_msiof_spi_txrx_once(p, tx_fifo, rx_fifo, tx_buf, rx_buf,
 949					   words, bits);
 950		if (n < 0)
 951			return n;
 952
 953		if (tx_buf)
 954			tx_buf += n * bytes_per_word;
 955		if (rx_buf)
 956			rx_buf += n * bytes_per_word;
 957		words -= n;
 
 
 
 
 
 
 
 
 958	}
 959
 960	return 0;
 961}
 962
 963static const struct sh_msiof_chipdata sh_data = {
 
 
 
 
 
 
 
 
 
 
 964	.tx_fifo_size = 64,
 965	.rx_fifo_size = 64,
 966	.master_flags = 0,
 
 967};
 968
 969static const struct sh_msiof_chipdata r8a779x_data = {
 
 
 970	.tx_fifo_size = 64,
 971	.rx_fifo_size = 64,
 972	.master_flags = SPI_MASTER_MUST_TX,
 
 973};
 974
 975static const struct of_device_id sh_msiof_match[] = {
 976	{ .compatible = "renesas,sh-mobile-msiof", .data = &sh_data },
 977	{ .compatible = "renesas,msiof-r8a7790",   .data = &r8a779x_data },
 978	{ .compatible = "renesas,msiof-r8a7791",   .data = &r8a779x_data },
 979	{ .compatible = "renesas,msiof-r8a7792",   .data = &r8a779x_data },
 980	{ .compatible = "renesas,msiof-r8a7793",   .data = &r8a779x_data },
 981	{ .compatible = "renesas,msiof-r8a7794",   .data = &r8a779x_data },
 982	{ .compatible = "renesas,rcar-gen2-msiof", .data = &r8a779x_data },
 983	{ .compatible = "renesas,msiof-r8a7796",   .data = &r8a779x_data },
 984	{ .compatible = "renesas,rcar-gen3-msiof", .data = &r8a779x_data },
 
 
 985	{ .compatible = "renesas,sh-msiof",        .data = &sh_data }, /* Deprecated */
 986	{},
 987};
 988MODULE_DEVICE_TABLE(of, sh_msiof_match);
 989
 990#ifdef CONFIG_OF
 991static struct sh_msiof_spi_info *sh_msiof_spi_parse_dt(struct device *dev)
 992{
 993	struct sh_msiof_spi_info *info;
 994	struct device_node *np = dev->of_node;
 995	u32 num_cs = 1;
 996
 997	info = devm_kzalloc(dev, sizeof(struct sh_msiof_spi_info), GFP_KERNEL);
 998	if (!info)
 999		return NULL;
1000
 
 
 
1001	/* Parse the MSIOF properties */
1002	of_property_read_u32(np, "num-cs", &num_cs);
 
1003	of_property_read_u32(np, "renesas,tx-fifo-size",
1004					&info->tx_fifo_override);
1005	of_property_read_u32(np, "renesas,rx-fifo-size",
1006					&info->rx_fifo_override);
1007	of_property_read_u32(np, "renesas,dtdl", &info->dtdl);
1008	of_property_read_u32(np, "renesas,syncdl", &info->syncdl);
1009
1010	info->num_chipselect = num_cs;
1011
1012	return info;
1013}
1014#else
1015static struct sh_msiof_spi_info *sh_msiof_spi_parse_dt(struct device *dev)
1016{
1017	return NULL;
1018}
1019#endif
1020
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1021static struct dma_chan *sh_msiof_request_dma_chan(struct device *dev,
1022	enum dma_transfer_direction dir, unsigned int id, dma_addr_t port_addr)
1023{
1024	dma_cap_mask_t mask;
1025	struct dma_chan *chan;
1026	struct dma_slave_config cfg;
1027	int ret;
1028
1029	dma_cap_zero(mask);
1030	dma_cap_set(DMA_SLAVE, mask);
1031
1032	chan = dma_request_slave_channel_compat(mask, shdma_chan_filter,
1033				(void *)(unsigned long)id, dev,
1034				dir == DMA_MEM_TO_DEV ? "tx" : "rx");
1035	if (!chan) {
1036		dev_warn(dev, "dma_request_slave_channel_compat failed\n");
1037		return NULL;
1038	}
1039
1040	memset(&cfg, 0, sizeof(cfg));
1041	cfg.direction = dir;
1042	if (dir == DMA_MEM_TO_DEV) {
1043		cfg.dst_addr = port_addr;
1044		cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1045	} else {
1046		cfg.src_addr = port_addr;
1047		cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1048	}
1049
1050	ret = dmaengine_slave_config(chan, &cfg);
1051	if (ret) {
1052		dev_warn(dev, "dmaengine_slave_config failed %d\n", ret);
1053		dma_release_channel(chan);
1054		return NULL;
1055	}
1056
1057	return chan;
1058}
1059
1060static int sh_msiof_request_dma(struct sh_msiof_spi_priv *p)
1061{
1062	struct platform_device *pdev = p->pdev;
1063	struct device *dev = &pdev->dev;
1064	const struct sh_msiof_spi_info *info = dev_get_platdata(dev);
1065	unsigned int dma_tx_id, dma_rx_id;
1066	const struct resource *res;
1067	struct spi_master *master;
1068	struct device *tx_dev, *rx_dev;
1069
1070	if (dev->of_node) {
1071		/* In the OF case we will get the slave IDs from the DT */
1072		dma_tx_id = 0;
1073		dma_rx_id = 0;
1074	} else if (info && info->dma_tx_id && info->dma_rx_id) {
1075		dma_tx_id = info->dma_tx_id;
1076		dma_rx_id = info->dma_rx_id;
1077	} else {
1078		/* The driver assumes no error */
1079		return 0;
1080	}
1081
1082	/* The DMA engine uses the second register set, if present */
1083	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
1084	if (!res)
1085		res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1086
1087	master = p->master;
1088	master->dma_tx = sh_msiof_request_dma_chan(dev, DMA_MEM_TO_DEV,
1089						   dma_tx_id,
1090						   res->start + TFDR);
1091	if (!master->dma_tx)
1092		return -ENODEV;
1093
1094	master->dma_rx = sh_msiof_request_dma_chan(dev, DMA_DEV_TO_MEM,
1095						   dma_rx_id,
1096						   res->start + RFDR);
1097	if (!master->dma_rx)
1098		goto free_tx_chan;
1099
1100	p->tx_dma_page = (void *)__get_free_page(GFP_KERNEL | GFP_DMA);
1101	if (!p->tx_dma_page)
1102		goto free_rx_chan;
1103
1104	p->rx_dma_page = (void *)__get_free_page(GFP_KERNEL | GFP_DMA);
1105	if (!p->rx_dma_page)
1106		goto free_tx_page;
1107
1108	tx_dev = master->dma_tx->device->dev;
1109	p->tx_dma_addr = dma_map_single(tx_dev, p->tx_dma_page, PAGE_SIZE,
1110					DMA_TO_DEVICE);
1111	if (dma_mapping_error(tx_dev, p->tx_dma_addr))
1112		goto free_rx_page;
1113
1114	rx_dev = master->dma_rx->device->dev;
1115	p->rx_dma_addr = dma_map_single(rx_dev, p->rx_dma_page, PAGE_SIZE,
1116					DMA_FROM_DEVICE);
1117	if (dma_mapping_error(rx_dev, p->rx_dma_addr))
1118		goto unmap_tx_page;
1119
1120	dev_info(dev, "DMA available");
1121	return 0;
1122
1123unmap_tx_page:
1124	dma_unmap_single(tx_dev, p->tx_dma_addr, PAGE_SIZE, DMA_TO_DEVICE);
1125free_rx_page:
1126	free_page((unsigned long)p->rx_dma_page);
1127free_tx_page:
1128	free_page((unsigned long)p->tx_dma_page);
1129free_rx_chan:
1130	dma_release_channel(master->dma_rx);
1131free_tx_chan:
1132	dma_release_channel(master->dma_tx);
1133	master->dma_tx = NULL;
1134	return -ENODEV;
1135}
1136
1137static void sh_msiof_release_dma(struct sh_msiof_spi_priv *p)
1138{
1139	struct spi_master *master = p->master;
1140	struct device *dev;
1141
1142	if (!master->dma_tx)
1143		return;
1144
1145	dev = &p->pdev->dev;
1146	dma_unmap_single(master->dma_rx->device->dev, p->rx_dma_addr,
1147			 PAGE_SIZE, DMA_FROM_DEVICE);
1148	dma_unmap_single(master->dma_tx->device->dev, p->tx_dma_addr,
1149			 PAGE_SIZE, DMA_TO_DEVICE);
1150	free_page((unsigned long)p->rx_dma_page);
1151	free_page((unsigned long)p->tx_dma_page);
1152	dma_release_channel(master->dma_rx);
1153	dma_release_channel(master->dma_tx);
1154}
1155
1156static int sh_msiof_spi_probe(struct platform_device *pdev)
1157{
1158	struct resource	*r;
1159	struct spi_master *master;
1160	const struct sh_msiof_chipdata *chipdata;
1161	const struct of_device_id *of_id;
1162	struct sh_msiof_spi_priv *p;
1163	int i;
1164	int ret;
1165
1166	master = spi_alloc_master(&pdev->dev, sizeof(struct sh_msiof_spi_priv));
1167	if (master == NULL) {
1168		dev_err(&pdev->dev, "failed to allocate spi master\n");
1169		return -ENOMEM;
1170	}
1171
1172	p = spi_master_get_devdata(master);
1173
1174	platform_set_drvdata(pdev, p);
1175	p->master = master;
1176
1177	of_id = of_match_device(sh_msiof_match, &pdev->dev);
1178	if (of_id) {
1179		chipdata = of_id->data;
1180		p->info = sh_msiof_spi_parse_dt(&pdev->dev);
1181	} else {
1182		chipdata = (const void *)pdev->id_entry->driver_data;
1183		p->info = dev_get_platdata(&pdev->dev);
1184	}
1185
1186	if (!p->info) {
1187		dev_err(&pdev->dev, "failed to obtain device info\n");
1188		ret = -ENXIO;
1189		goto err1;
1190	}
1191
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1192	init_completion(&p->done);
 
1193
1194	p->clk = devm_clk_get(&pdev->dev, NULL);
1195	if (IS_ERR(p->clk)) {
1196		dev_err(&pdev->dev, "cannot get clock\n");
1197		ret = PTR_ERR(p->clk);
1198		goto err1;
1199	}
1200
1201	i = platform_get_irq(pdev, 0);
1202	if (i < 0) {
1203		dev_err(&pdev->dev, "cannot get platform IRQ\n");
1204		ret = -ENOENT;
1205		goto err1;
1206	}
1207
1208	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1209	p->mapbase = devm_ioremap_resource(&pdev->dev, r);
1210	if (IS_ERR(p->mapbase)) {
1211		ret = PTR_ERR(p->mapbase);
1212		goto err1;
1213	}
1214
1215	ret = devm_request_irq(&pdev->dev, i, sh_msiof_spi_irq, 0,
1216			       dev_name(&pdev->dev), p);
1217	if (ret) {
1218		dev_err(&pdev->dev, "unable to request irq\n");
1219		goto err1;
1220	}
1221
1222	p->pdev = pdev;
1223	pm_runtime_enable(&pdev->dev);
1224
1225	/* Platform data may override FIFO sizes */
1226	p->tx_fifo_size = chipdata->tx_fifo_size;
1227	p->rx_fifo_size = chipdata->rx_fifo_size;
1228	if (p->info->tx_fifo_override)
1229		p->tx_fifo_size = p->info->tx_fifo_override;
1230	if (p->info->rx_fifo_override)
1231		p->rx_fifo_size = p->info->rx_fifo_override;
1232
1233	/* init master code */
1234	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH;
1235	master->mode_bits |= SPI_LSB_FIRST | SPI_3WIRE;
1236	master->flags = chipdata->master_flags;
1237	master->bus_num = pdev->id;
1238	master->dev.of_node = pdev->dev.of_node;
1239	master->num_chipselect = p->info->num_chipselect;
1240	master->setup = sh_msiof_spi_setup;
1241	master->prepare_message = sh_msiof_prepare_message;
1242	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(8, 32);
1243	master->auto_runtime_pm = true;
1244	master->transfer_one = sh_msiof_transfer_one;
 
 
 
 
 
 
 
1245
1246	ret = sh_msiof_request_dma(p);
1247	if (ret < 0)
1248		dev_warn(&pdev->dev, "DMA not available, using PIO\n");
1249
1250	ret = devm_spi_register_master(&pdev->dev, master);
1251	if (ret < 0) {
1252		dev_err(&pdev->dev, "spi_register_master error.\n");
1253		goto err2;
1254	}
1255
1256	return 0;
1257
1258 err2:
1259	sh_msiof_release_dma(p);
1260	pm_runtime_disable(&pdev->dev);
1261 err1:
1262	spi_master_put(master);
1263	return ret;
1264}
1265
1266static int sh_msiof_spi_remove(struct platform_device *pdev)
1267{
1268	struct sh_msiof_spi_priv *p = platform_get_drvdata(pdev);
1269
1270	sh_msiof_release_dma(p);
1271	pm_runtime_disable(&pdev->dev);
1272	return 0;
1273}
1274
1275static const struct platform_device_id spi_driver_ids[] = {
1276	{ "spi_sh_msiof",	(kernel_ulong_t)&sh_data },
1277	{},
1278};
1279MODULE_DEVICE_TABLE(platform, spi_driver_ids);
1280
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1281static struct platform_driver sh_msiof_spi_drv = {
1282	.probe		= sh_msiof_spi_probe,
1283	.remove		= sh_msiof_spi_remove,
1284	.id_table	= spi_driver_ids,
1285	.driver		= {
1286		.name		= "spi_sh_msiof",
 
1287		.of_match_table = of_match_ptr(sh_msiof_match),
1288	},
1289};
1290module_platform_driver(sh_msiof_spi_drv);
1291
1292MODULE_DESCRIPTION("SuperH MSIOF SPI Master Interface Driver");
1293MODULE_AUTHOR("Magnus Damm");
1294MODULE_LICENSE("GPL v2");
1295MODULE_ALIAS("platform:spi_sh_msiof");