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   1// SPDX-License-Identifier: GPL-2.0
   2//
   3// Mediatek SPI NOR controller driver
   4//
   5// Copyright (C) 2020 Chuanhong Guo <gch981213@gmail.com>
   6
   7#include <linux/bits.h>
   8#include <linux/clk.h>
   9#include <linux/completion.h>
  10#include <linux/dma-mapping.h>
  11#include <linux/interrupt.h>
  12#include <linux/io.h>
  13#include <linux/iopoll.h>
  14#include <linux/kernel.h>
  15#include <linux/module.h>
  16#include <linux/of_device.h>
  17#include <linux/pm_runtime.h>
  18#include <linux/spi/spi.h>
  19#include <linux/spi/spi-mem.h>
  20#include <linux/string.h>
  21
  22#define DRIVER_NAME "mtk-spi-nor"
  23
  24#define MTK_NOR_REG_CMD			0x00
  25#define MTK_NOR_CMD_WRITE		BIT(4)
  26#define MTK_NOR_CMD_PROGRAM		BIT(2)
  27#define MTK_NOR_CMD_READ		BIT(0)
  28#define MTK_NOR_CMD_MASK		GENMASK(5, 0)
  29
  30#define MTK_NOR_REG_PRG_CNT		0x04
  31#define MTK_NOR_PRG_CNT_MAX		56
  32#define MTK_NOR_REG_RDATA		0x0c
  33
  34#define MTK_NOR_REG_RADR0		0x10
  35#define MTK_NOR_REG_RADR(n)		(MTK_NOR_REG_RADR0 + 4 * (n))
  36#define MTK_NOR_REG_RADR3		0xc8
  37
  38#define MTK_NOR_REG_WDATA		0x1c
  39
  40#define MTK_NOR_REG_PRGDATA0		0x20
  41#define MTK_NOR_REG_PRGDATA(n)		(MTK_NOR_REG_PRGDATA0 + 4 * (n))
  42#define MTK_NOR_REG_PRGDATA_MAX		5
  43
  44#define MTK_NOR_REG_SHIFT0		0x38
  45#define MTK_NOR_REG_SHIFT(n)		(MTK_NOR_REG_SHIFT0 + 4 * (n))
  46#define MTK_NOR_REG_SHIFT_MAX		9
  47
  48#define MTK_NOR_REG_CFG1		0x60
  49#define MTK_NOR_FAST_READ		BIT(0)
  50
  51#define MTK_NOR_REG_CFG2		0x64
  52#define MTK_NOR_WR_CUSTOM_OP_EN		BIT(4)
  53#define MTK_NOR_WR_BUF_EN		BIT(0)
  54
  55#define MTK_NOR_REG_PP_DATA		0x98
  56
  57#define MTK_NOR_REG_IRQ_STAT		0xa8
  58#define MTK_NOR_REG_IRQ_EN		0xac
  59#define MTK_NOR_IRQ_DMA			BIT(7)
  60#define MTK_NOR_IRQ_MASK		GENMASK(7, 0)
  61
  62#define MTK_NOR_REG_CFG3		0xb4
  63#define MTK_NOR_DISABLE_WREN		BIT(7)
  64#define MTK_NOR_DISABLE_SR_POLL		BIT(5)
  65
  66#define MTK_NOR_REG_WP			0xc4
  67#define MTK_NOR_ENABLE_SF_CMD		0x30
  68
  69#define MTK_NOR_REG_BUSCFG		0xcc
  70#define MTK_NOR_4B_ADDR			BIT(4)
  71#define MTK_NOR_QUAD_ADDR		BIT(3)
  72#define MTK_NOR_QUAD_READ		BIT(2)
  73#define MTK_NOR_DUAL_ADDR		BIT(1)
  74#define MTK_NOR_DUAL_READ		BIT(0)
  75#define MTK_NOR_BUS_MODE_MASK		GENMASK(4, 0)
  76
  77#define MTK_NOR_REG_DMA_CTL		0x718
  78#define MTK_NOR_DMA_START		BIT(0)
  79
  80#define MTK_NOR_REG_DMA_FADR		0x71c
  81#define MTK_NOR_REG_DMA_DADR		0x720
  82#define MTK_NOR_REG_DMA_END_DADR	0x724
  83#define MTK_NOR_REG_CG_DIS		0x728
  84#define MTK_NOR_SFC_SW_RST		BIT(2)
  85
  86#define MTK_NOR_REG_DMA_DADR_HB		0x738
  87#define MTK_NOR_REG_DMA_END_DADR_HB	0x73c
  88
  89#define MTK_NOR_PRG_MAX_SIZE		6
  90// Reading DMA src/dst addresses have to be 16-byte aligned
  91#define MTK_NOR_DMA_ALIGN		16
  92#define MTK_NOR_DMA_ALIGN_MASK		(MTK_NOR_DMA_ALIGN - 1)
  93// and we allocate a bounce buffer if destination address isn't aligned.
  94#define MTK_NOR_BOUNCE_BUF_SIZE		PAGE_SIZE
  95
  96// Buffered page program can do one 128-byte transfer
  97#define MTK_NOR_PP_SIZE			128
  98
  99#define CLK_TO_US(sp, clkcnt)		DIV_ROUND_UP(clkcnt, sp->spi_freq / 1000000)
 100
 101struct mtk_nor_caps {
 102	u8 dma_bits;
 103
 104	/* extra_dummy_bit is adding for the IP of new SoCs.
 105	 * Some new SoCs modify the timing of fetching registers' values
 106	 * and IDs of nor flash, they need a extra_dummy_bit which can add
 107	 * more clock cycles for fetching data.
 108	 */
 109	u8 extra_dummy_bit;
 110};
 111
 112struct mtk_nor {
 113	struct spi_controller *ctlr;
 114	struct device *dev;
 115	void __iomem *base;
 116	u8 *buffer;
 117	dma_addr_t buffer_dma;
 118	struct clk *spi_clk;
 119	struct clk *ctlr_clk;
 120	struct clk *axi_clk;
 121	struct clk *axi_s_clk;
 122	unsigned int spi_freq;
 123	bool wbuf_en;
 124	bool has_irq;
 125	bool high_dma;
 126	struct completion op_done;
 127	const struct mtk_nor_caps *caps;
 128};
 129
 130static inline void mtk_nor_rmw(struct mtk_nor *sp, u32 reg, u32 set, u32 clr)
 131{
 132	u32 val = readl(sp->base + reg);
 133
 134	val &= ~clr;
 135	val |= set;
 136	writel(val, sp->base + reg);
 137}
 138
 139static inline int mtk_nor_cmd_exec(struct mtk_nor *sp, u32 cmd, ulong clk)
 140{
 141	ulong delay = CLK_TO_US(sp, clk);
 142	u32 reg;
 143	int ret;
 144
 145	writel(cmd, sp->base + MTK_NOR_REG_CMD);
 146	ret = readl_poll_timeout(sp->base + MTK_NOR_REG_CMD, reg, !(reg & cmd),
 147				 delay / 3, (delay + 1) * 200);
 148	if (ret < 0)
 149		dev_err(sp->dev, "command %u timeout.\n", cmd);
 150	return ret;
 151}
 152
 153static void mtk_nor_reset(struct mtk_nor *sp)
 154{
 155	mtk_nor_rmw(sp, MTK_NOR_REG_CG_DIS, 0, MTK_NOR_SFC_SW_RST);
 156	mb(); /* flush previous writes */
 157	mtk_nor_rmw(sp, MTK_NOR_REG_CG_DIS, MTK_NOR_SFC_SW_RST, 0);
 158	mb(); /* flush previous writes */
 159	writel(MTK_NOR_ENABLE_SF_CMD, sp->base + MTK_NOR_REG_WP);
 160}
 161
 162static void mtk_nor_set_addr(struct mtk_nor *sp, const struct spi_mem_op *op)
 163{
 164	u32 addr = op->addr.val;
 165	int i;
 166
 167	for (i = 0; i < 3; i++) {
 168		writeb(addr & 0xff, sp->base + MTK_NOR_REG_RADR(i));
 169		addr >>= 8;
 170	}
 171	if (op->addr.nbytes == 4) {
 172		writeb(addr & 0xff, sp->base + MTK_NOR_REG_RADR3);
 173		mtk_nor_rmw(sp, MTK_NOR_REG_BUSCFG, MTK_NOR_4B_ADDR, 0);
 174	} else {
 175		mtk_nor_rmw(sp, MTK_NOR_REG_BUSCFG, 0, MTK_NOR_4B_ADDR);
 176	}
 177}
 178
 179static bool need_bounce(struct mtk_nor *sp, const struct spi_mem_op *op)
 180{
 181	return ((uintptr_t)op->data.buf.in & MTK_NOR_DMA_ALIGN_MASK);
 182}
 183
 184static bool mtk_nor_match_read(const struct spi_mem_op *op)
 185{
 186	int dummy = 0;
 187
 188	if (op->dummy.nbytes)
 189		dummy = op->dummy.nbytes * BITS_PER_BYTE / op->dummy.buswidth;
 190
 191	if ((op->data.buswidth == 2) || (op->data.buswidth == 4)) {
 192		if (op->addr.buswidth == 1)
 193			return dummy == 8;
 194		else if (op->addr.buswidth == 2)
 195			return dummy == 4;
 196		else if (op->addr.buswidth == 4)
 197			return dummy == 6;
 198	} else if ((op->addr.buswidth == 1) && (op->data.buswidth == 1)) {
 199		if (op->cmd.opcode == 0x03)
 200			return dummy == 0;
 201		else if (op->cmd.opcode == 0x0b)
 202			return dummy == 8;
 203	}
 204	return false;
 205}
 206
 207static bool mtk_nor_match_prg(const struct spi_mem_op *op)
 208{
 209	int tx_len, rx_len, prg_len, prg_left;
 210
 211	// prg mode is spi-only.
 212	if ((op->cmd.buswidth > 1) || (op->addr.buswidth > 1) ||
 213	    (op->dummy.buswidth > 1) || (op->data.buswidth > 1))
 214		return false;
 215
 216	tx_len = op->cmd.nbytes + op->addr.nbytes;
 217
 218	if (op->data.dir == SPI_MEM_DATA_OUT) {
 219		// count dummy bytes only if we need to write data after it
 220		tx_len += op->dummy.nbytes;
 221
 222		// leave at least one byte for data
 223		if (tx_len > MTK_NOR_REG_PRGDATA_MAX)
 224			return false;
 225
 226		// if there's no addr, meaning adjust_op_size is impossible,
 227		// check data length as well.
 228		if ((!op->addr.nbytes) &&
 229		    (tx_len + op->data.nbytes > MTK_NOR_REG_PRGDATA_MAX + 1))
 230			return false;
 231	} else if (op->data.dir == SPI_MEM_DATA_IN) {
 232		if (tx_len > MTK_NOR_REG_PRGDATA_MAX + 1)
 233			return false;
 234
 235		rx_len = op->data.nbytes;
 236		prg_left = MTK_NOR_PRG_CNT_MAX / 8 - tx_len - op->dummy.nbytes;
 237		if (prg_left > MTK_NOR_REG_SHIFT_MAX + 1)
 238			prg_left = MTK_NOR_REG_SHIFT_MAX + 1;
 239		if (rx_len > prg_left) {
 240			if (!op->addr.nbytes)
 241				return false;
 242			rx_len = prg_left;
 243		}
 244
 245		prg_len = tx_len + op->dummy.nbytes + rx_len;
 246		if (prg_len > MTK_NOR_PRG_CNT_MAX / 8)
 247			return false;
 248	} else {
 249		prg_len = tx_len + op->dummy.nbytes;
 250		if (prg_len > MTK_NOR_PRG_CNT_MAX / 8)
 251			return false;
 252	}
 253	return true;
 254}
 255
 256static void mtk_nor_adj_prg_size(struct spi_mem_op *op)
 257{
 258	int tx_len, tx_left, prg_left;
 259
 260	tx_len = op->cmd.nbytes + op->addr.nbytes;
 261	if (op->data.dir == SPI_MEM_DATA_OUT) {
 262		tx_len += op->dummy.nbytes;
 263		tx_left = MTK_NOR_REG_PRGDATA_MAX + 1 - tx_len;
 264		if (op->data.nbytes > tx_left)
 265			op->data.nbytes = tx_left;
 266	} else if (op->data.dir == SPI_MEM_DATA_IN) {
 267		prg_left = MTK_NOR_PRG_CNT_MAX / 8 - tx_len - op->dummy.nbytes;
 268		if (prg_left > MTK_NOR_REG_SHIFT_MAX + 1)
 269			prg_left = MTK_NOR_REG_SHIFT_MAX + 1;
 270		if (op->data.nbytes > prg_left)
 271			op->data.nbytes = prg_left;
 272	}
 273}
 274
 275static int mtk_nor_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op)
 276{
 277	struct mtk_nor *sp = spi_controller_get_devdata(mem->spi->master);
 278
 279	if (!op->data.nbytes)
 280		return 0;
 281
 282	if ((op->addr.nbytes == 3) || (op->addr.nbytes == 4)) {
 283		if ((op->data.dir == SPI_MEM_DATA_IN) &&
 284		    mtk_nor_match_read(op)) {
 285			// limit size to prevent timeout calculation overflow
 286			if (op->data.nbytes > 0x400000)
 287				op->data.nbytes = 0x400000;
 288
 289			if ((op->addr.val & MTK_NOR_DMA_ALIGN_MASK) ||
 290			    (op->data.nbytes < MTK_NOR_DMA_ALIGN))
 291				op->data.nbytes = 1;
 292			else if (!need_bounce(sp, op))
 293				op->data.nbytes &= ~MTK_NOR_DMA_ALIGN_MASK;
 294			else if (op->data.nbytes > MTK_NOR_BOUNCE_BUF_SIZE)
 295				op->data.nbytes = MTK_NOR_BOUNCE_BUF_SIZE;
 296			return 0;
 297		} else if (op->data.dir == SPI_MEM_DATA_OUT) {
 298			if (op->data.nbytes >= MTK_NOR_PP_SIZE)
 299				op->data.nbytes = MTK_NOR_PP_SIZE;
 300			else
 301				op->data.nbytes = 1;
 302			return 0;
 303		}
 304	}
 305
 306	mtk_nor_adj_prg_size(op);
 307	return 0;
 308}
 309
 310static bool mtk_nor_supports_op(struct spi_mem *mem,
 311				const struct spi_mem_op *op)
 312{
 313	if (!spi_mem_default_supports_op(mem, op))
 314		return false;
 315
 316	if (op->cmd.buswidth != 1)
 317		return false;
 318
 319	if ((op->addr.nbytes == 3) || (op->addr.nbytes == 4)) {
 320		switch (op->data.dir) {
 321		case SPI_MEM_DATA_IN:
 322			if (mtk_nor_match_read(op))
 323				return true;
 324			break;
 325		case SPI_MEM_DATA_OUT:
 326			if ((op->addr.buswidth == 1) &&
 327			    (op->dummy.nbytes == 0) &&
 328			    (op->data.buswidth == 1))
 329				return true;
 330			break;
 331		default:
 332			break;
 333		}
 334	}
 335
 336	return mtk_nor_match_prg(op);
 337}
 338
 339static void mtk_nor_setup_bus(struct mtk_nor *sp, const struct spi_mem_op *op)
 340{
 341	u32 reg = 0;
 342
 343	if (op->addr.nbytes == 4)
 344		reg |= MTK_NOR_4B_ADDR;
 345
 346	if (op->data.buswidth == 4) {
 347		reg |= MTK_NOR_QUAD_READ;
 348		writeb(op->cmd.opcode, sp->base + MTK_NOR_REG_PRGDATA(4));
 349		if (op->addr.buswidth == 4)
 350			reg |= MTK_NOR_QUAD_ADDR;
 351	} else if (op->data.buswidth == 2) {
 352		reg |= MTK_NOR_DUAL_READ;
 353		writeb(op->cmd.opcode, sp->base + MTK_NOR_REG_PRGDATA(3));
 354		if (op->addr.buswidth == 2)
 355			reg |= MTK_NOR_DUAL_ADDR;
 356	} else {
 357		if (op->cmd.opcode == 0x0b)
 358			mtk_nor_rmw(sp, MTK_NOR_REG_CFG1, MTK_NOR_FAST_READ, 0);
 359		else
 360			mtk_nor_rmw(sp, MTK_NOR_REG_CFG1, 0, MTK_NOR_FAST_READ);
 361	}
 362	mtk_nor_rmw(sp, MTK_NOR_REG_BUSCFG, reg, MTK_NOR_BUS_MODE_MASK);
 363}
 364
 365static int mtk_nor_dma_exec(struct mtk_nor *sp, u32 from, unsigned int length,
 366			    dma_addr_t dma_addr)
 367{
 368	int ret = 0;
 369	u32 delay, timeout;
 370	u32 reg;
 371
 372	writel(from, sp->base + MTK_NOR_REG_DMA_FADR);
 373	writel(dma_addr, sp->base + MTK_NOR_REG_DMA_DADR);
 374	writel(dma_addr + length, sp->base + MTK_NOR_REG_DMA_END_DADR);
 375
 376	if (sp->high_dma) {
 377		writel(upper_32_bits(dma_addr),
 378		       sp->base + MTK_NOR_REG_DMA_DADR_HB);
 379		writel(upper_32_bits(dma_addr + length),
 380		       sp->base + MTK_NOR_REG_DMA_END_DADR_HB);
 381	}
 382
 383	if (sp->has_irq) {
 384		reinit_completion(&sp->op_done);
 385		mtk_nor_rmw(sp, MTK_NOR_REG_IRQ_EN, MTK_NOR_IRQ_DMA, 0);
 386	}
 387
 388	mtk_nor_rmw(sp, MTK_NOR_REG_DMA_CTL, MTK_NOR_DMA_START, 0);
 389
 390	delay = CLK_TO_US(sp, (length + 5) * BITS_PER_BYTE);
 391	timeout = (delay + 1) * 100;
 392
 393	if (sp->has_irq) {
 394		if (!wait_for_completion_timeout(&sp->op_done,
 395		    usecs_to_jiffies(max(timeout, 10000U))))
 396			ret = -ETIMEDOUT;
 397	} else {
 398		ret = readl_poll_timeout(sp->base + MTK_NOR_REG_DMA_CTL, reg,
 399					 !(reg & MTK_NOR_DMA_START), delay / 3,
 400					 timeout);
 401	}
 402
 403	if (ret < 0)
 404		dev_err(sp->dev, "dma read timeout.\n");
 405
 406	return ret;
 407}
 408
 409static int mtk_nor_read_bounce(struct mtk_nor *sp, const struct spi_mem_op *op)
 410{
 411	unsigned int rdlen;
 412	int ret;
 413
 414	if (op->data.nbytes & MTK_NOR_DMA_ALIGN_MASK)
 415		rdlen = (op->data.nbytes + MTK_NOR_DMA_ALIGN) & ~MTK_NOR_DMA_ALIGN_MASK;
 416	else
 417		rdlen = op->data.nbytes;
 418
 419	ret = mtk_nor_dma_exec(sp, op->addr.val, rdlen, sp->buffer_dma);
 420
 421	if (!ret)
 422		memcpy(op->data.buf.in, sp->buffer, op->data.nbytes);
 423
 424	return ret;
 425}
 426
 427static int mtk_nor_read_dma(struct mtk_nor *sp, const struct spi_mem_op *op)
 428{
 429	int ret;
 430	dma_addr_t dma_addr;
 431
 432	if (need_bounce(sp, op))
 433		return mtk_nor_read_bounce(sp, op);
 434
 435	dma_addr = dma_map_single(sp->dev, op->data.buf.in,
 436				  op->data.nbytes, DMA_FROM_DEVICE);
 437
 438	if (dma_mapping_error(sp->dev, dma_addr))
 439		return -EINVAL;
 440
 441	ret = mtk_nor_dma_exec(sp, op->addr.val, op->data.nbytes, dma_addr);
 442
 443	dma_unmap_single(sp->dev, dma_addr, op->data.nbytes, DMA_FROM_DEVICE);
 444
 445	return ret;
 446}
 447
 448static int mtk_nor_read_pio(struct mtk_nor *sp, const struct spi_mem_op *op)
 449{
 450	u8 *buf = op->data.buf.in;
 451	int ret;
 452
 453	ret = mtk_nor_cmd_exec(sp, MTK_NOR_CMD_READ, 6 * BITS_PER_BYTE);
 454	if (!ret)
 455		buf[0] = readb(sp->base + MTK_NOR_REG_RDATA);
 456	return ret;
 457}
 458
 459static int mtk_nor_setup_write_buffer(struct mtk_nor *sp, bool on)
 460{
 461	int ret;
 462	u32 val;
 463
 464	if (!(sp->wbuf_en ^ on))
 465		return 0;
 466
 467	val = readl(sp->base + MTK_NOR_REG_CFG2);
 468	if (on) {
 469		writel(val | MTK_NOR_WR_BUF_EN, sp->base + MTK_NOR_REG_CFG2);
 470		ret = readl_poll_timeout(sp->base + MTK_NOR_REG_CFG2, val,
 471					 val & MTK_NOR_WR_BUF_EN, 0, 10000);
 472	} else {
 473		writel(val & ~MTK_NOR_WR_BUF_EN, sp->base + MTK_NOR_REG_CFG2);
 474		ret = readl_poll_timeout(sp->base + MTK_NOR_REG_CFG2, val,
 475					 !(val & MTK_NOR_WR_BUF_EN), 0, 10000);
 476	}
 477
 478	if (!ret)
 479		sp->wbuf_en = on;
 480
 481	return ret;
 482}
 483
 484static int mtk_nor_pp_buffered(struct mtk_nor *sp, const struct spi_mem_op *op)
 485{
 486	const u8 *buf = op->data.buf.out;
 487	u32 val;
 488	int ret, i;
 489
 490	ret = mtk_nor_setup_write_buffer(sp, true);
 491	if (ret < 0)
 492		return ret;
 493
 494	for (i = 0; i < op->data.nbytes; i += 4) {
 495		val = buf[i + 3] << 24 | buf[i + 2] << 16 | buf[i + 1] << 8 |
 496		      buf[i];
 497		writel(val, sp->base + MTK_NOR_REG_PP_DATA);
 498	}
 499	return mtk_nor_cmd_exec(sp, MTK_NOR_CMD_WRITE,
 500				(op->data.nbytes + 5) * BITS_PER_BYTE);
 501}
 502
 503static int mtk_nor_pp_unbuffered(struct mtk_nor *sp,
 504				 const struct spi_mem_op *op)
 505{
 506	const u8 *buf = op->data.buf.out;
 507	int ret;
 508
 509	ret = mtk_nor_setup_write_buffer(sp, false);
 510	if (ret < 0)
 511		return ret;
 512	writeb(buf[0], sp->base + MTK_NOR_REG_WDATA);
 513	return mtk_nor_cmd_exec(sp, MTK_NOR_CMD_WRITE, 6 * BITS_PER_BYTE);
 514}
 515
 516static int mtk_nor_spi_mem_prg(struct mtk_nor *sp, const struct spi_mem_op *op)
 517{
 518	int rx_len = 0;
 519	int reg_offset = MTK_NOR_REG_PRGDATA_MAX;
 520	int tx_len, prg_len;
 521	int i, ret;
 522	void __iomem *reg;
 523	u8 bufbyte;
 524
 525	tx_len = op->cmd.nbytes + op->addr.nbytes;
 526
 527	// count dummy bytes only if we need to write data after it
 528	if (op->data.dir == SPI_MEM_DATA_OUT)
 529		tx_len += op->dummy.nbytes + op->data.nbytes;
 530	else if (op->data.dir == SPI_MEM_DATA_IN)
 531		rx_len = op->data.nbytes;
 532
 533	prg_len = op->cmd.nbytes + op->addr.nbytes + op->dummy.nbytes +
 534		  op->data.nbytes;
 535
 536	// an invalid op may reach here if the caller calls exec_op without
 537	// adjust_op_size. return -EINVAL instead of -ENOTSUPP so that
 538	// spi-mem won't try this op again with generic spi transfers.
 539	if ((tx_len > MTK_NOR_REG_PRGDATA_MAX + 1) ||
 540	    (rx_len > MTK_NOR_REG_SHIFT_MAX + 1) ||
 541	    (prg_len > MTK_NOR_PRG_CNT_MAX / 8))
 542		return -EINVAL;
 543
 544	// fill tx data
 545	for (i = op->cmd.nbytes; i > 0; i--, reg_offset--) {
 546		reg = sp->base + MTK_NOR_REG_PRGDATA(reg_offset);
 547		bufbyte = (op->cmd.opcode >> ((i - 1) * BITS_PER_BYTE)) & 0xff;
 548		writeb(bufbyte, reg);
 549	}
 550
 551	for (i = op->addr.nbytes; i > 0; i--, reg_offset--) {
 552		reg = sp->base + MTK_NOR_REG_PRGDATA(reg_offset);
 553		bufbyte = (op->addr.val >> ((i - 1) * BITS_PER_BYTE)) & 0xff;
 554		writeb(bufbyte, reg);
 555	}
 556
 557	if (op->data.dir == SPI_MEM_DATA_OUT) {
 558		for (i = 0; i < op->dummy.nbytes; i++, reg_offset--) {
 559			reg = sp->base + MTK_NOR_REG_PRGDATA(reg_offset);
 560			writeb(0, reg);
 561		}
 562
 563		for (i = 0; i < op->data.nbytes; i++, reg_offset--) {
 564			reg = sp->base + MTK_NOR_REG_PRGDATA(reg_offset);
 565			writeb(((const u8 *)(op->data.buf.out))[i], reg);
 566		}
 567	}
 568
 569	for (; reg_offset >= 0; reg_offset--) {
 570		reg = sp->base + MTK_NOR_REG_PRGDATA(reg_offset);
 571		writeb(0, reg);
 572	}
 573
 574	// trigger op
 575	if (rx_len)
 576		writel(prg_len * BITS_PER_BYTE + sp->caps->extra_dummy_bit,
 577		       sp->base + MTK_NOR_REG_PRG_CNT);
 578	else
 579		writel(prg_len * BITS_PER_BYTE, sp->base + MTK_NOR_REG_PRG_CNT);
 580
 581	ret = mtk_nor_cmd_exec(sp, MTK_NOR_CMD_PROGRAM,
 582			       prg_len * BITS_PER_BYTE);
 583	if (ret)
 584		return ret;
 585
 586	// fetch read data
 587	reg_offset = 0;
 588	if (op->data.dir == SPI_MEM_DATA_IN) {
 589		for (i = op->data.nbytes - 1; i >= 0; i--, reg_offset++) {
 590			reg = sp->base + MTK_NOR_REG_SHIFT(reg_offset);
 591			((u8 *)(op->data.buf.in))[i] = readb(reg);
 592		}
 593	}
 594
 595	return 0;
 596}
 597
 598static int mtk_nor_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
 599{
 600	struct mtk_nor *sp = spi_controller_get_devdata(mem->spi->master);
 601	int ret;
 602
 603	if ((op->data.nbytes == 0) ||
 604	    ((op->addr.nbytes != 3) && (op->addr.nbytes != 4)))
 605		return mtk_nor_spi_mem_prg(sp, op);
 606
 607	if (op->data.dir == SPI_MEM_DATA_OUT) {
 608		mtk_nor_set_addr(sp, op);
 609		writeb(op->cmd.opcode, sp->base + MTK_NOR_REG_PRGDATA0);
 610		if (op->data.nbytes == MTK_NOR_PP_SIZE)
 611			return mtk_nor_pp_buffered(sp, op);
 612		return mtk_nor_pp_unbuffered(sp, op);
 613	}
 614
 615	if ((op->data.dir == SPI_MEM_DATA_IN) && mtk_nor_match_read(op)) {
 616		ret = mtk_nor_setup_write_buffer(sp, false);
 617		if (ret < 0)
 618			return ret;
 619		mtk_nor_setup_bus(sp, op);
 620		if (op->data.nbytes == 1) {
 621			mtk_nor_set_addr(sp, op);
 622			return mtk_nor_read_pio(sp, op);
 623		} else {
 624			ret = mtk_nor_read_dma(sp, op);
 625			if (unlikely(ret)) {
 626				/* Handle rare bus glitch */
 627				mtk_nor_reset(sp);
 628				mtk_nor_setup_bus(sp, op);
 629				return mtk_nor_read_dma(sp, op);
 630			}
 631
 632			return ret;
 633		}
 634	}
 635
 636	return mtk_nor_spi_mem_prg(sp, op);
 637}
 638
 639static int mtk_nor_setup(struct spi_device *spi)
 640{
 641	struct mtk_nor *sp = spi_controller_get_devdata(spi->master);
 642
 643	if (spi->max_speed_hz && (spi->max_speed_hz < sp->spi_freq)) {
 644		dev_err(&spi->dev, "spi clock should be %u Hz.\n",
 645			sp->spi_freq);
 646		return -EINVAL;
 647	}
 648	spi->max_speed_hz = sp->spi_freq;
 649
 650	return 0;
 651}
 652
 653static int mtk_nor_transfer_one_message(struct spi_controller *master,
 654					struct spi_message *m)
 655{
 656	struct mtk_nor *sp = spi_controller_get_devdata(master);
 657	struct spi_transfer *t = NULL;
 658	unsigned long trx_len = 0;
 659	int stat = 0;
 660	int reg_offset = MTK_NOR_REG_PRGDATA_MAX;
 661	void __iomem *reg;
 662	const u8 *txbuf;
 663	u8 *rxbuf;
 664	int i;
 665
 666	list_for_each_entry(t, &m->transfers, transfer_list) {
 667		txbuf = t->tx_buf;
 668		for (i = 0; i < t->len; i++, reg_offset--) {
 669			reg = sp->base + MTK_NOR_REG_PRGDATA(reg_offset);
 670			if (txbuf)
 671				writeb(txbuf[i], reg);
 672			else
 673				writeb(0, reg);
 674		}
 675		trx_len += t->len;
 676	}
 677
 678	writel(trx_len * BITS_PER_BYTE, sp->base + MTK_NOR_REG_PRG_CNT);
 679
 680	stat = mtk_nor_cmd_exec(sp, MTK_NOR_CMD_PROGRAM,
 681				trx_len * BITS_PER_BYTE);
 682	if (stat < 0)
 683		goto msg_done;
 684
 685	reg_offset = trx_len - 1;
 686	list_for_each_entry(t, &m->transfers, transfer_list) {
 687		rxbuf = t->rx_buf;
 688		for (i = 0; i < t->len; i++, reg_offset--) {
 689			reg = sp->base + MTK_NOR_REG_SHIFT(reg_offset);
 690			if (rxbuf)
 691				rxbuf[i] = readb(reg);
 692		}
 693	}
 694
 695	m->actual_length = trx_len;
 696msg_done:
 697	m->status = stat;
 698	spi_finalize_current_message(master);
 699
 700	return 0;
 701}
 702
 703static void mtk_nor_disable_clk(struct mtk_nor *sp)
 704{
 705	clk_disable_unprepare(sp->spi_clk);
 706	clk_disable_unprepare(sp->ctlr_clk);
 707	clk_disable_unprepare(sp->axi_clk);
 708	clk_disable_unprepare(sp->axi_s_clk);
 709}
 710
 711static int mtk_nor_enable_clk(struct mtk_nor *sp)
 712{
 713	int ret;
 714
 715	ret = clk_prepare_enable(sp->spi_clk);
 716	if (ret)
 717		return ret;
 718
 719	ret = clk_prepare_enable(sp->ctlr_clk);
 720	if (ret) {
 721		clk_disable_unprepare(sp->spi_clk);
 722		return ret;
 723	}
 724
 725	ret = clk_prepare_enable(sp->axi_clk);
 726	if (ret) {
 727		clk_disable_unprepare(sp->spi_clk);
 728		clk_disable_unprepare(sp->ctlr_clk);
 729		return ret;
 730	}
 731
 732	ret = clk_prepare_enable(sp->axi_s_clk);
 733	if (ret) {
 734		clk_disable_unprepare(sp->spi_clk);
 735		clk_disable_unprepare(sp->ctlr_clk);
 736		clk_disable_unprepare(sp->axi_clk);
 737		return ret;
 738	}
 739
 740	return 0;
 741}
 742
 743static void mtk_nor_init(struct mtk_nor *sp)
 744{
 745	writel(0, sp->base + MTK_NOR_REG_IRQ_EN);
 746	writel(MTK_NOR_IRQ_MASK, sp->base + MTK_NOR_REG_IRQ_STAT);
 747
 748	writel(MTK_NOR_ENABLE_SF_CMD, sp->base + MTK_NOR_REG_WP);
 749	mtk_nor_rmw(sp, MTK_NOR_REG_CFG2, MTK_NOR_WR_CUSTOM_OP_EN, 0);
 750	mtk_nor_rmw(sp, MTK_NOR_REG_CFG3,
 751		    MTK_NOR_DISABLE_WREN | MTK_NOR_DISABLE_SR_POLL, 0);
 752}
 753
 754static irqreturn_t mtk_nor_irq_handler(int irq, void *data)
 755{
 756	struct mtk_nor *sp = data;
 757	u32 irq_status, irq_enabled;
 758
 759	irq_status = readl(sp->base + MTK_NOR_REG_IRQ_STAT);
 760	irq_enabled = readl(sp->base + MTK_NOR_REG_IRQ_EN);
 761	// write status back to clear interrupt
 762	writel(irq_status, sp->base + MTK_NOR_REG_IRQ_STAT);
 763
 764	if (!(irq_status & irq_enabled))
 765		return IRQ_NONE;
 766
 767	if (irq_status & MTK_NOR_IRQ_DMA) {
 768		complete(&sp->op_done);
 769		writel(0, sp->base + MTK_NOR_REG_IRQ_EN);
 770	}
 771
 772	return IRQ_HANDLED;
 773}
 774
 775static size_t mtk_max_msg_size(struct spi_device *spi)
 776{
 777	return MTK_NOR_PRG_MAX_SIZE;
 778}
 779
 780static const struct spi_controller_mem_ops mtk_nor_mem_ops = {
 781	.adjust_op_size = mtk_nor_adjust_op_size,
 782	.supports_op = mtk_nor_supports_op,
 783	.exec_op = mtk_nor_exec_op
 784};
 785
 786static const struct mtk_nor_caps mtk_nor_caps_mt8173 = {
 787	.dma_bits = 32,
 788	.extra_dummy_bit = 0,
 789};
 790
 791static const struct mtk_nor_caps mtk_nor_caps_mt8186 = {
 792	.dma_bits = 32,
 793	.extra_dummy_bit = 1,
 794};
 795
 796static const struct mtk_nor_caps mtk_nor_caps_mt8192 = {
 797	.dma_bits = 36,
 798	.extra_dummy_bit = 0,
 799};
 800
 801static const struct of_device_id mtk_nor_match[] = {
 802	{ .compatible = "mediatek,mt8173-nor", .data = &mtk_nor_caps_mt8173 },
 803	{ .compatible = "mediatek,mt8186-nor", .data = &mtk_nor_caps_mt8186 },
 804	{ .compatible = "mediatek,mt8192-nor", .data = &mtk_nor_caps_mt8192 },
 805	{ /* sentinel */ }
 806};
 807MODULE_DEVICE_TABLE(of, mtk_nor_match);
 808
 809static int mtk_nor_probe(struct platform_device *pdev)
 810{
 811	struct spi_controller *ctlr;
 812	struct mtk_nor *sp;
 813	struct mtk_nor_caps *caps;
 814	void __iomem *base;
 815	struct clk *spi_clk, *ctlr_clk, *axi_clk, *axi_s_clk;
 816	int ret, irq;
 817
 818	base = devm_platform_ioremap_resource(pdev, 0);
 819	if (IS_ERR(base))
 820		return PTR_ERR(base);
 821
 822	spi_clk = devm_clk_get(&pdev->dev, "spi");
 823	if (IS_ERR(spi_clk))
 824		return PTR_ERR(spi_clk);
 825
 826	ctlr_clk = devm_clk_get(&pdev->dev, "sf");
 827	if (IS_ERR(ctlr_clk))
 828		return PTR_ERR(ctlr_clk);
 829
 830	axi_clk = devm_clk_get_optional(&pdev->dev, "axi");
 831	if (IS_ERR(axi_clk))
 832		return PTR_ERR(axi_clk);
 833
 834	axi_s_clk = devm_clk_get_optional(&pdev->dev, "axi_s");
 835	if (IS_ERR(axi_s_clk))
 836		return PTR_ERR(axi_s_clk);
 837
 838	caps = (struct mtk_nor_caps *)of_device_get_match_data(&pdev->dev);
 839
 840	ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(caps->dma_bits));
 841	if (ret) {
 842		dev_err(&pdev->dev, "failed to set dma mask(%u)\n", caps->dma_bits);
 843		return ret;
 844	}
 845
 846	ctlr = devm_spi_alloc_master(&pdev->dev, sizeof(*sp));
 847	if (!ctlr) {
 848		dev_err(&pdev->dev, "failed to allocate spi controller\n");
 849		return -ENOMEM;
 850	}
 851
 852	ctlr->bits_per_word_mask = SPI_BPW_MASK(8);
 853	ctlr->dev.of_node = pdev->dev.of_node;
 854	ctlr->max_message_size = mtk_max_msg_size;
 855	ctlr->mem_ops = &mtk_nor_mem_ops;
 856	ctlr->mode_bits = SPI_RX_DUAL | SPI_RX_QUAD | SPI_TX_DUAL | SPI_TX_QUAD;
 857	ctlr->num_chipselect = 1;
 858	ctlr->setup = mtk_nor_setup;
 859	ctlr->transfer_one_message = mtk_nor_transfer_one_message;
 860	ctlr->auto_runtime_pm = true;
 861
 862	dev_set_drvdata(&pdev->dev, ctlr);
 863
 864	sp = spi_controller_get_devdata(ctlr);
 865	sp->base = base;
 866	sp->has_irq = false;
 867	sp->wbuf_en = false;
 868	sp->ctlr = ctlr;
 869	sp->dev = &pdev->dev;
 870	sp->spi_clk = spi_clk;
 871	sp->ctlr_clk = ctlr_clk;
 872	sp->axi_clk = axi_clk;
 873	sp->axi_s_clk = axi_s_clk;
 874	sp->caps = caps;
 875	sp->high_dma = caps->dma_bits > 32;
 876	sp->buffer = dmam_alloc_coherent(&pdev->dev,
 877				MTK_NOR_BOUNCE_BUF_SIZE + MTK_NOR_DMA_ALIGN,
 878				&sp->buffer_dma, GFP_KERNEL);
 879	if (!sp->buffer)
 880		return -ENOMEM;
 881
 882	if ((uintptr_t)sp->buffer & MTK_NOR_DMA_ALIGN_MASK) {
 883		dev_err(sp->dev, "misaligned allocation of internal buffer.\n");
 884		return -ENOMEM;
 885	}
 886
 887	ret = mtk_nor_enable_clk(sp);
 888	if (ret < 0)
 889		return ret;
 890
 891	sp->spi_freq = clk_get_rate(sp->spi_clk);
 892
 893	mtk_nor_init(sp);
 894
 895	irq = platform_get_irq_optional(pdev, 0);
 896
 897	if (irq < 0) {
 898		dev_warn(sp->dev, "IRQ not available.");
 899	} else {
 900		ret = devm_request_irq(sp->dev, irq, mtk_nor_irq_handler, 0,
 901				       pdev->name, sp);
 902		if (ret < 0) {
 903			dev_warn(sp->dev, "failed to request IRQ.");
 904		} else {
 905			init_completion(&sp->op_done);
 906			sp->has_irq = true;
 907		}
 908	}
 909
 910	pm_runtime_set_autosuspend_delay(&pdev->dev, -1);
 911	pm_runtime_use_autosuspend(&pdev->dev);
 912	pm_runtime_set_active(&pdev->dev);
 913	pm_runtime_enable(&pdev->dev);
 914	pm_runtime_get_noresume(&pdev->dev);
 915
 916	ret = devm_spi_register_controller(&pdev->dev, ctlr);
 917	if (ret < 0)
 918		goto err_probe;
 919
 920	pm_runtime_mark_last_busy(&pdev->dev);
 921	pm_runtime_put_autosuspend(&pdev->dev);
 922
 923	dev_info(&pdev->dev, "spi frequency: %d Hz\n", sp->spi_freq);
 924
 925	return 0;
 926
 927err_probe:
 928	pm_runtime_disable(&pdev->dev);
 929	pm_runtime_set_suspended(&pdev->dev);
 930	pm_runtime_dont_use_autosuspend(&pdev->dev);
 931
 932	mtk_nor_disable_clk(sp);
 933
 934	return ret;
 935}
 936
 937static int mtk_nor_remove(struct platform_device *pdev)
 938{
 939	struct spi_controller *ctlr = dev_get_drvdata(&pdev->dev);
 940	struct mtk_nor *sp = spi_controller_get_devdata(ctlr);
 941
 942	pm_runtime_disable(&pdev->dev);
 943	pm_runtime_set_suspended(&pdev->dev);
 944	pm_runtime_dont_use_autosuspend(&pdev->dev);
 945
 946	mtk_nor_disable_clk(sp);
 947
 948	return 0;
 949}
 950
 951static int __maybe_unused mtk_nor_runtime_suspend(struct device *dev)
 952{
 953	struct spi_controller *ctlr = dev_get_drvdata(dev);
 954	struct mtk_nor *sp = spi_controller_get_devdata(ctlr);
 955
 956	mtk_nor_disable_clk(sp);
 957
 958	return 0;
 959}
 960
 961static int __maybe_unused mtk_nor_runtime_resume(struct device *dev)
 962{
 963	struct spi_controller *ctlr = dev_get_drvdata(dev);
 964	struct mtk_nor *sp = spi_controller_get_devdata(ctlr);
 965
 966	return mtk_nor_enable_clk(sp);
 967}
 968
 969static int __maybe_unused mtk_nor_suspend(struct device *dev)
 970{
 971	return pm_runtime_force_suspend(dev);
 972}
 973
 974static int __maybe_unused mtk_nor_resume(struct device *dev)
 975{
 976	struct spi_controller *ctlr = dev_get_drvdata(dev);
 977	struct mtk_nor *sp = spi_controller_get_devdata(ctlr);
 978	int ret;
 979
 980	ret = pm_runtime_force_resume(dev);
 981	if (ret)
 982		return ret;
 983
 984	mtk_nor_init(sp);
 985
 986	return 0;
 987}
 988
 989static const struct dev_pm_ops mtk_nor_pm_ops = {
 990	SET_RUNTIME_PM_OPS(mtk_nor_runtime_suspend,
 991			   mtk_nor_runtime_resume, NULL)
 992	SET_SYSTEM_SLEEP_PM_OPS(mtk_nor_suspend, mtk_nor_resume)
 993};
 994
 995static struct platform_driver mtk_nor_driver = {
 996	.driver = {
 997		.name = DRIVER_NAME,
 998		.of_match_table = mtk_nor_match,
 999		.pm = &mtk_nor_pm_ops,
1000	},
1001	.probe = mtk_nor_probe,
1002	.remove = mtk_nor_remove,
1003};
1004
1005module_platform_driver(mtk_nor_driver);
1006
1007MODULE_DESCRIPTION("Mediatek SPI NOR controller driver");
1008MODULE_AUTHOR("Chuanhong Guo <gch981213@gmail.com>");
1009MODULE_LICENSE("GPL v2");
1010MODULE_ALIAS("platform:" DRIVER_NAME);