xref: /openbmc/linux/drivers/spi/spi-ti-qspi.c (revision 715f23b6)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * TI QSPI driver
4  *
5  * Copyright (C) 2013 Texas Instruments Incorporated - http://www.ti.com
6  * Author: Sourav Poddar <sourav.poddar@ti.com>
7  */
8 
9 #include <linux/kernel.h>
10 #include <linux/init.h>
11 #include <linux/interrupt.h>
12 #include <linux/module.h>
13 #include <linux/device.h>
14 #include <linux/delay.h>
15 #include <linux/dma-mapping.h>
16 #include <linux/dmaengine.h>
17 #include <linux/omap-dma.h>
18 #include <linux/platform_device.h>
19 #include <linux/err.h>
20 #include <linux/clk.h>
21 #include <linux/io.h>
22 #include <linux/slab.h>
23 #include <linux/pm_runtime.h>
24 #include <linux/of.h>
25 #include <linux/of_device.h>
26 #include <linux/pinctrl/consumer.h>
27 #include <linux/mfd/syscon.h>
28 #include <linux/regmap.h>
29 #include <linux/sizes.h>
30 
31 #include <linux/spi/spi.h>
32 #include <linux/spi/spi-mem.h>
33 
34 struct ti_qspi_regs {
35 	u32 clkctrl;
36 };
37 
38 struct ti_qspi {
39 	struct completion	transfer_complete;
40 
41 	/* list synchronization */
42 	struct mutex            list_lock;
43 
44 	struct spi_master	*master;
45 	void __iomem            *base;
46 	void __iomem            *mmap_base;
47 	size_t			mmap_size;
48 	struct regmap		*ctrl_base;
49 	unsigned int		ctrl_reg;
50 	struct clk		*fclk;
51 	struct device           *dev;
52 
53 	struct ti_qspi_regs     ctx_reg;
54 
55 	dma_addr_t		mmap_phys_base;
56 	dma_addr_t		rx_bb_dma_addr;
57 	void			*rx_bb_addr;
58 	struct dma_chan		*rx_chan;
59 
60 	u32 spi_max_frequency;
61 	u32 cmd;
62 	u32 dc;
63 
64 	bool mmap_enabled;
65 	int current_cs;
66 };
67 
68 #define QSPI_PID			(0x0)
69 #define QSPI_SYSCONFIG			(0x10)
70 #define QSPI_SPI_CLOCK_CNTRL_REG	(0x40)
71 #define QSPI_SPI_DC_REG			(0x44)
72 #define QSPI_SPI_CMD_REG		(0x48)
73 #define QSPI_SPI_STATUS_REG		(0x4c)
74 #define QSPI_SPI_DATA_REG		(0x50)
75 #define QSPI_SPI_SETUP_REG(n)		((0x54 + 4 * n))
76 #define QSPI_SPI_SWITCH_REG		(0x64)
77 #define QSPI_SPI_DATA_REG_1		(0x68)
78 #define QSPI_SPI_DATA_REG_2		(0x6c)
79 #define QSPI_SPI_DATA_REG_3		(0x70)
80 
81 #define QSPI_COMPLETION_TIMEOUT		msecs_to_jiffies(2000)
82 
83 #define QSPI_FCLK			192000000
84 
85 /* Clock Control */
86 #define QSPI_CLK_EN			(1 << 31)
87 #define QSPI_CLK_DIV_MAX		0xffff
88 
89 /* Command */
90 #define QSPI_EN_CS(n)			(n << 28)
91 #define QSPI_WLEN(n)			((n - 1) << 19)
92 #define QSPI_3_PIN			(1 << 18)
93 #define QSPI_RD_SNGL			(1 << 16)
94 #define QSPI_WR_SNGL			(2 << 16)
95 #define QSPI_RD_DUAL			(3 << 16)
96 #define QSPI_RD_QUAD			(7 << 16)
97 #define QSPI_INVAL			(4 << 16)
98 #define QSPI_FLEN(n)			((n - 1) << 0)
99 #define QSPI_WLEN_MAX_BITS		128
100 #define QSPI_WLEN_MAX_BYTES		16
101 #define QSPI_WLEN_MASK			QSPI_WLEN(QSPI_WLEN_MAX_BITS)
102 
103 /* STATUS REGISTER */
104 #define BUSY				0x01
105 #define WC				0x02
106 
107 /* Device Control */
108 #define QSPI_DD(m, n)			(m << (3 + n * 8))
109 #define QSPI_CKPHA(n)			(1 << (2 + n * 8))
110 #define QSPI_CSPOL(n)			(1 << (1 + n * 8))
111 #define QSPI_CKPOL(n)			(1 << (n * 8))
112 
113 #define	QSPI_FRAME			4096
114 
115 #define QSPI_AUTOSUSPEND_TIMEOUT         2000
116 
117 #define MEM_CS_EN(n)			((n + 1) << 8)
118 #define MEM_CS_MASK			(7 << 8)
119 
120 #define MM_SWITCH			0x1
121 
122 #define QSPI_SETUP_RD_NORMAL		(0x0 << 12)
123 #define QSPI_SETUP_RD_DUAL		(0x1 << 12)
124 #define QSPI_SETUP_RD_QUAD		(0x3 << 12)
125 #define QSPI_SETUP_ADDR_SHIFT		8
126 #define QSPI_SETUP_DUMMY_SHIFT		10
127 
128 #define QSPI_DMA_BUFFER_SIZE            SZ_64K
129 
130 static inline unsigned long ti_qspi_read(struct ti_qspi *qspi,
131 		unsigned long reg)
132 {
133 	return readl(qspi->base + reg);
134 }
135 
136 static inline void ti_qspi_write(struct ti_qspi *qspi,
137 		unsigned long val, unsigned long reg)
138 {
139 	writel(val, qspi->base + reg);
140 }
141 
142 static int ti_qspi_setup(struct spi_device *spi)
143 {
144 	struct ti_qspi	*qspi = spi_master_get_devdata(spi->master);
145 	struct ti_qspi_regs *ctx_reg = &qspi->ctx_reg;
146 	int clk_div = 0, ret;
147 	u32 clk_ctrl_reg, clk_rate, clk_mask;
148 
149 	if (spi->master->busy) {
150 		dev_dbg(qspi->dev, "master busy doing other transfers\n");
151 		return -EBUSY;
152 	}
153 
154 	if (!qspi->spi_max_frequency) {
155 		dev_err(qspi->dev, "spi max frequency not defined\n");
156 		return -EINVAL;
157 	}
158 
159 	clk_rate = clk_get_rate(qspi->fclk);
160 
161 	clk_div = DIV_ROUND_UP(clk_rate, qspi->spi_max_frequency) - 1;
162 
163 	if (clk_div < 0) {
164 		dev_dbg(qspi->dev, "clock divider < 0, using /1 divider\n");
165 		return -EINVAL;
166 	}
167 
168 	if (clk_div > QSPI_CLK_DIV_MAX) {
169 		dev_dbg(qspi->dev, "clock divider >%d , using /%d divider\n",
170 				QSPI_CLK_DIV_MAX, QSPI_CLK_DIV_MAX + 1);
171 		return -EINVAL;
172 	}
173 
174 	dev_dbg(qspi->dev, "hz: %d, clock divider %d\n",
175 			qspi->spi_max_frequency, clk_div);
176 
177 	ret = pm_runtime_get_sync(qspi->dev);
178 	if (ret < 0) {
179 		dev_err(qspi->dev, "pm_runtime_get_sync() failed\n");
180 		return ret;
181 	}
182 
183 	clk_ctrl_reg = ti_qspi_read(qspi, QSPI_SPI_CLOCK_CNTRL_REG);
184 
185 	clk_ctrl_reg &= ~QSPI_CLK_EN;
186 
187 	/* disable SCLK */
188 	ti_qspi_write(qspi, clk_ctrl_reg, QSPI_SPI_CLOCK_CNTRL_REG);
189 
190 	/* enable SCLK */
191 	clk_mask = QSPI_CLK_EN | clk_div;
192 	ti_qspi_write(qspi, clk_mask, QSPI_SPI_CLOCK_CNTRL_REG);
193 	ctx_reg->clkctrl = clk_mask;
194 
195 	pm_runtime_mark_last_busy(qspi->dev);
196 	ret = pm_runtime_put_autosuspend(qspi->dev);
197 	if (ret < 0) {
198 		dev_err(qspi->dev, "pm_runtime_put_autosuspend() failed\n");
199 		return ret;
200 	}
201 
202 	return 0;
203 }
204 
205 static void ti_qspi_restore_ctx(struct ti_qspi *qspi)
206 {
207 	struct ti_qspi_regs *ctx_reg = &qspi->ctx_reg;
208 
209 	ti_qspi_write(qspi, ctx_reg->clkctrl, QSPI_SPI_CLOCK_CNTRL_REG);
210 }
211 
212 static inline u32 qspi_is_busy(struct ti_qspi *qspi)
213 {
214 	u32 stat;
215 	unsigned long timeout = jiffies + QSPI_COMPLETION_TIMEOUT;
216 
217 	stat = ti_qspi_read(qspi, QSPI_SPI_STATUS_REG);
218 	while ((stat & BUSY) && time_after(timeout, jiffies)) {
219 		cpu_relax();
220 		stat = ti_qspi_read(qspi, QSPI_SPI_STATUS_REG);
221 	}
222 
223 	WARN(stat & BUSY, "qspi busy\n");
224 	return stat & BUSY;
225 }
226 
227 static inline int ti_qspi_poll_wc(struct ti_qspi *qspi)
228 {
229 	u32 stat;
230 	unsigned long timeout = jiffies + QSPI_COMPLETION_TIMEOUT;
231 
232 	do {
233 		stat = ti_qspi_read(qspi, QSPI_SPI_STATUS_REG);
234 		if (stat & WC)
235 			return 0;
236 		cpu_relax();
237 	} while (time_after(timeout, jiffies));
238 
239 	stat = ti_qspi_read(qspi, QSPI_SPI_STATUS_REG);
240 	if (stat & WC)
241 		return 0;
242 	return  -ETIMEDOUT;
243 }
244 
245 static int qspi_write_msg(struct ti_qspi *qspi, struct spi_transfer *t,
246 			  int count)
247 {
248 	int wlen, xfer_len;
249 	unsigned int cmd;
250 	const u8 *txbuf;
251 	u32 data;
252 
253 	txbuf = t->tx_buf;
254 	cmd = qspi->cmd | QSPI_WR_SNGL;
255 	wlen = t->bits_per_word >> 3;	/* in bytes */
256 	xfer_len = wlen;
257 
258 	while (count) {
259 		if (qspi_is_busy(qspi))
260 			return -EBUSY;
261 
262 		switch (wlen) {
263 		case 1:
264 			dev_dbg(qspi->dev, "tx cmd %08x dc %08x data %02x\n",
265 					cmd, qspi->dc, *txbuf);
266 			if (count >= QSPI_WLEN_MAX_BYTES) {
267 				u32 *txp = (u32 *)txbuf;
268 
269 				data = cpu_to_be32(*txp++);
270 				writel(data, qspi->base +
271 				       QSPI_SPI_DATA_REG_3);
272 				data = cpu_to_be32(*txp++);
273 				writel(data, qspi->base +
274 				       QSPI_SPI_DATA_REG_2);
275 				data = cpu_to_be32(*txp++);
276 				writel(data, qspi->base +
277 				       QSPI_SPI_DATA_REG_1);
278 				data = cpu_to_be32(*txp++);
279 				writel(data, qspi->base +
280 				       QSPI_SPI_DATA_REG);
281 				xfer_len = QSPI_WLEN_MAX_BYTES;
282 				cmd |= QSPI_WLEN(QSPI_WLEN_MAX_BITS);
283 			} else {
284 				writeb(*txbuf, qspi->base + QSPI_SPI_DATA_REG);
285 				cmd = qspi->cmd | QSPI_WR_SNGL;
286 				xfer_len = wlen;
287 				cmd |= QSPI_WLEN(wlen);
288 			}
289 			break;
290 		case 2:
291 			dev_dbg(qspi->dev, "tx cmd %08x dc %08x data %04x\n",
292 					cmd, qspi->dc, *txbuf);
293 			writew(*((u16 *)txbuf), qspi->base + QSPI_SPI_DATA_REG);
294 			break;
295 		case 4:
296 			dev_dbg(qspi->dev, "tx cmd %08x dc %08x data %08x\n",
297 					cmd, qspi->dc, *txbuf);
298 			writel(*((u32 *)txbuf), qspi->base + QSPI_SPI_DATA_REG);
299 			break;
300 		}
301 
302 		ti_qspi_write(qspi, cmd, QSPI_SPI_CMD_REG);
303 		if (ti_qspi_poll_wc(qspi)) {
304 			dev_err(qspi->dev, "write timed out\n");
305 			return -ETIMEDOUT;
306 		}
307 		txbuf += xfer_len;
308 		count -= xfer_len;
309 	}
310 
311 	return 0;
312 }
313 
314 static int qspi_read_msg(struct ti_qspi *qspi, struct spi_transfer *t,
315 			 int count)
316 {
317 	int wlen;
318 	unsigned int cmd;
319 	u8 *rxbuf;
320 
321 	rxbuf = t->rx_buf;
322 	cmd = qspi->cmd;
323 	switch (t->rx_nbits) {
324 	case SPI_NBITS_DUAL:
325 		cmd |= QSPI_RD_DUAL;
326 		break;
327 	case SPI_NBITS_QUAD:
328 		cmd |= QSPI_RD_QUAD;
329 		break;
330 	default:
331 		cmd |= QSPI_RD_SNGL;
332 		break;
333 	}
334 	wlen = t->bits_per_word >> 3;	/* in bytes */
335 
336 	while (count) {
337 		dev_dbg(qspi->dev, "rx cmd %08x dc %08x\n", cmd, qspi->dc);
338 		if (qspi_is_busy(qspi))
339 			return -EBUSY;
340 
341 		ti_qspi_write(qspi, cmd, QSPI_SPI_CMD_REG);
342 		if (ti_qspi_poll_wc(qspi)) {
343 			dev_err(qspi->dev, "read timed out\n");
344 			return -ETIMEDOUT;
345 		}
346 		switch (wlen) {
347 		case 1:
348 			*rxbuf = readb(qspi->base + QSPI_SPI_DATA_REG);
349 			break;
350 		case 2:
351 			*((u16 *)rxbuf) = readw(qspi->base + QSPI_SPI_DATA_REG);
352 			break;
353 		case 4:
354 			*((u32 *)rxbuf) = readl(qspi->base + QSPI_SPI_DATA_REG);
355 			break;
356 		}
357 		rxbuf += wlen;
358 		count -= wlen;
359 	}
360 
361 	return 0;
362 }
363 
364 static int qspi_transfer_msg(struct ti_qspi *qspi, struct spi_transfer *t,
365 			     int count)
366 {
367 	int ret;
368 
369 	if (t->tx_buf) {
370 		ret = qspi_write_msg(qspi, t, count);
371 		if (ret) {
372 			dev_dbg(qspi->dev, "Error while writing\n");
373 			return ret;
374 		}
375 	}
376 
377 	if (t->rx_buf) {
378 		ret = qspi_read_msg(qspi, t, count);
379 		if (ret) {
380 			dev_dbg(qspi->dev, "Error while reading\n");
381 			return ret;
382 		}
383 	}
384 
385 	return 0;
386 }
387 
388 static void ti_qspi_dma_callback(void *param)
389 {
390 	struct ti_qspi *qspi = param;
391 
392 	complete(&qspi->transfer_complete);
393 }
394 
395 static int ti_qspi_dma_xfer(struct ti_qspi *qspi, dma_addr_t dma_dst,
396 			    dma_addr_t dma_src, size_t len)
397 {
398 	struct dma_chan *chan = qspi->rx_chan;
399 	dma_cookie_t cookie;
400 	enum dma_ctrl_flags flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
401 	struct dma_async_tx_descriptor *tx;
402 	int ret;
403 
404 	tx = dmaengine_prep_dma_memcpy(chan, dma_dst, dma_src, len, flags);
405 	if (!tx) {
406 		dev_err(qspi->dev, "device_prep_dma_memcpy error\n");
407 		return -EIO;
408 	}
409 
410 	tx->callback = ti_qspi_dma_callback;
411 	tx->callback_param = qspi;
412 	cookie = tx->tx_submit(tx);
413 	reinit_completion(&qspi->transfer_complete);
414 
415 	ret = dma_submit_error(cookie);
416 	if (ret) {
417 		dev_err(qspi->dev, "dma_submit_error %d\n", cookie);
418 		return -EIO;
419 	}
420 
421 	dma_async_issue_pending(chan);
422 	ret = wait_for_completion_timeout(&qspi->transfer_complete,
423 					  msecs_to_jiffies(len));
424 	if (ret <= 0) {
425 		dmaengine_terminate_sync(chan);
426 		dev_err(qspi->dev, "DMA wait_for_completion_timeout\n");
427 		return -ETIMEDOUT;
428 	}
429 
430 	return 0;
431 }
432 
433 static int ti_qspi_dma_bounce_buffer(struct ti_qspi *qspi, loff_t offs,
434 				     void *to, size_t readsize)
435 {
436 	dma_addr_t dma_src = qspi->mmap_phys_base + offs;
437 	int ret = 0;
438 
439 	/*
440 	 * Use bounce buffer as FS like jffs2, ubifs may pass
441 	 * buffers that does not belong to kernel lowmem region.
442 	 */
443 	while (readsize != 0) {
444 		size_t xfer_len = min_t(size_t, QSPI_DMA_BUFFER_SIZE,
445 					readsize);
446 
447 		ret = ti_qspi_dma_xfer(qspi, qspi->rx_bb_dma_addr,
448 				       dma_src, xfer_len);
449 		if (ret != 0)
450 			return ret;
451 		memcpy(to, qspi->rx_bb_addr, xfer_len);
452 		readsize -= xfer_len;
453 		dma_src += xfer_len;
454 		to += xfer_len;
455 	}
456 
457 	return ret;
458 }
459 
460 static int ti_qspi_dma_xfer_sg(struct ti_qspi *qspi, struct sg_table rx_sg,
461 			       loff_t from)
462 {
463 	struct scatterlist *sg;
464 	dma_addr_t dma_src = qspi->mmap_phys_base + from;
465 	dma_addr_t dma_dst;
466 	int i, len, ret;
467 
468 	for_each_sg(rx_sg.sgl, sg, rx_sg.nents, i) {
469 		dma_dst = sg_dma_address(sg);
470 		len = sg_dma_len(sg);
471 		ret = ti_qspi_dma_xfer(qspi, dma_dst, dma_src, len);
472 		if (ret)
473 			return ret;
474 		dma_src += len;
475 	}
476 
477 	return 0;
478 }
479 
480 static void ti_qspi_enable_memory_map(struct spi_device *spi)
481 {
482 	struct ti_qspi  *qspi = spi_master_get_devdata(spi->master);
483 
484 	ti_qspi_write(qspi, MM_SWITCH, QSPI_SPI_SWITCH_REG);
485 	if (qspi->ctrl_base) {
486 		regmap_update_bits(qspi->ctrl_base, qspi->ctrl_reg,
487 				   MEM_CS_MASK,
488 				   MEM_CS_EN(spi->chip_select));
489 	}
490 	qspi->mmap_enabled = true;
491 	qspi->current_cs = spi->chip_select;
492 }
493 
494 static void ti_qspi_disable_memory_map(struct spi_device *spi)
495 {
496 	struct ti_qspi  *qspi = spi_master_get_devdata(spi->master);
497 
498 	ti_qspi_write(qspi, 0, QSPI_SPI_SWITCH_REG);
499 	if (qspi->ctrl_base)
500 		regmap_update_bits(qspi->ctrl_base, qspi->ctrl_reg,
501 				   MEM_CS_MASK, 0);
502 	qspi->mmap_enabled = false;
503 	qspi->current_cs = -1;
504 }
505 
506 static void ti_qspi_setup_mmap_read(struct spi_device *spi, u8 opcode,
507 				    u8 data_nbits, u8 addr_width,
508 				    u8 dummy_bytes)
509 {
510 	struct ti_qspi  *qspi = spi_master_get_devdata(spi->master);
511 	u32 memval = opcode;
512 
513 	switch (data_nbits) {
514 	case SPI_NBITS_QUAD:
515 		memval |= QSPI_SETUP_RD_QUAD;
516 		break;
517 	case SPI_NBITS_DUAL:
518 		memval |= QSPI_SETUP_RD_DUAL;
519 		break;
520 	default:
521 		memval |= QSPI_SETUP_RD_NORMAL;
522 		break;
523 	}
524 	memval |= ((addr_width - 1) << QSPI_SETUP_ADDR_SHIFT |
525 		   dummy_bytes << QSPI_SETUP_DUMMY_SHIFT);
526 	ti_qspi_write(qspi, memval,
527 		      QSPI_SPI_SETUP_REG(spi->chip_select));
528 }
529 
530 static int ti_qspi_exec_mem_op(struct spi_mem *mem,
531 			       const struct spi_mem_op *op)
532 {
533 	struct ti_qspi *qspi = spi_master_get_devdata(mem->spi->master);
534 	u32 from = 0;
535 	int ret = 0;
536 
537 	/* Only optimize read path. */
538 	if (!op->data.nbytes || op->data.dir != SPI_MEM_DATA_IN ||
539 	    !op->addr.nbytes || op->addr.nbytes > 4)
540 		return -ENOTSUPP;
541 
542 	/* Address exceeds MMIO window size, fall back to regular mode. */
543 	from = op->addr.val;
544 	if (from + op->data.nbytes > qspi->mmap_size)
545 		return -ENOTSUPP;
546 
547 	mutex_lock(&qspi->list_lock);
548 
549 	if (!qspi->mmap_enabled || qspi->current_cs != mem->spi->chip_select)
550 		ti_qspi_enable_memory_map(mem->spi);
551 	ti_qspi_setup_mmap_read(mem->spi, op->cmd.opcode, op->data.buswidth,
552 				op->addr.nbytes, op->dummy.nbytes);
553 
554 	if (qspi->rx_chan) {
555 		struct sg_table sgt;
556 
557 		if (virt_addr_valid(op->data.buf.in) &&
558 		    !spi_controller_dma_map_mem_op_data(mem->spi->master, op,
559 							&sgt)) {
560 			ret = ti_qspi_dma_xfer_sg(qspi, sgt, from);
561 			spi_controller_dma_unmap_mem_op_data(mem->spi->master,
562 							     op, &sgt);
563 		} else {
564 			ret = ti_qspi_dma_bounce_buffer(qspi, from,
565 							op->data.buf.in,
566 							op->data.nbytes);
567 		}
568 	} else {
569 		memcpy_fromio(op->data.buf.in, qspi->mmap_base + from,
570 			      op->data.nbytes);
571 	}
572 
573 	mutex_unlock(&qspi->list_lock);
574 
575 	return ret;
576 }
577 
578 static const struct spi_controller_mem_ops ti_qspi_mem_ops = {
579 	.exec_op = ti_qspi_exec_mem_op,
580 };
581 
582 static int ti_qspi_start_transfer_one(struct spi_master *master,
583 		struct spi_message *m)
584 {
585 	struct ti_qspi *qspi = spi_master_get_devdata(master);
586 	struct spi_device *spi = m->spi;
587 	struct spi_transfer *t;
588 	int status = 0, ret;
589 	unsigned int frame_len_words, transfer_len_words;
590 	int wlen;
591 
592 	/* setup device control reg */
593 	qspi->dc = 0;
594 
595 	if (spi->mode & SPI_CPHA)
596 		qspi->dc |= QSPI_CKPHA(spi->chip_select);
597 	if (spi->mode & SPI_CPOL)
598 		qspi->dc |= QSPI_CKPOL(spi->chip_select);
599 	if (spi->mode & SPI_CS_HIGH)
600 		qspi->dc |= QSPI_CSPOL(spi->chip_select);
601 
602 	frame_len_words = 0;
603 	list_for_each_entry(t, &m->transfers, transfer_list)
604 		frame_len_words += t->len / (t->bits_per_word >> 3);
605 	frame_len_words = min_t(unsigned int, frame_len_words, QSPI_FRAME);
606 
607 	/* setup command reg */
608 	qspi->cmd = 0;
609 	qspi->cmd |= QSPI_EN_CS(spi->chip_select);
610 	qspi->cmd |= QSPI_FLEN(frame_len_words);
611 
612 	ti_qspi_write(qspi, qspi->dc, QSPI_SPI_DC_REG);
613 
614 	mutex_lock(&qspi->list_lock);
615 
616 	if (qspi->mmap_enabled)
617 		ti_qspi_disable_memory_map(spi);
618 
619 	list_for_each_entry(t, &m->transfers, transfer_list) {
620 		qspi->cmd = ((qspi->cmd & ~QSPI_WLEN_MASK) |
621 			     QSPI_WLEN(t->bits_per_word));
622 
623 		wlen = t->bits_per_word >> 3;
624 		transfer_len_words = min(t->len / wlen, frame_len_words);
625 
626 		ret = qspi_transfer_msg(qspi, t, transfer_len_words * wlen);
627 		if (ret) {
628 			dev_dbg(qspi->dev, "transfer message failed\n");
629 			mutex_unlock(&qspi->list_lock);
630 			return -EINVAL;
631 		}
632 
633 		m->actual_length += transfer_len_words * wlen;
634 		frame_len_words -= transfer_len_words;
635 		if (frame_len_words == 0)
636 			break;
637 	}
638 
639 	mutex_unlock(&qspi->list_lock);
640 
641 	ti_qspi_write(qspi, qspi->cmd | QSPI_INVAL, QSPI_SPI_CMD_REG);
642 	m->status = status;
643 	spi_finalize_current_message(master);
644 
645 	return status;
646 }
647 
648 static int ti_qspi_runtime_resume(struct device *dev)
649 {
650 	struct ti_qspi      *qspi;
651 
652 	qspi = dev_get_drvdata(dev);
653 	ti_qspi_restore_ctx(qspi);
654 
655 	return 0;
656 }
657 
658 static const struct of_device_id ti_qspi_match[] = {
659 	{.compatible = "ti,dra7xxx-qspi" },
660 	{.compatible = "ti,am4372-qspi" },
661 	{},
662 };
663 MODULE_DEVICE_TABLE(of, ti_qspi_match);
664 
665 static int ti_qspi_probe(struct platform_device *pdev)
666 {
667 	struct  ti_qspi *qspi;
668 	struct spi_master *master;
669 	struct resource         *r, *res_mmap;
670 	struct device_node *np = pdev->dev.of_node;
671 	u32 max_freq;
672 	int ret = 0, num_cs, irq;
673 	dma_cap_mask_t mask;
674 
675 	master = spi_alloc_master(&pdev->dev, sizeof(*qspi));
676 	if (!master)
677 		return -ENOMEM;
678 
679 	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_RX_DUAL | SPI_RX_QUAD;
680 
681 	master->flags = SPI_MASTER_HALF_DUPLEX;
682 	master->setup = ti_qspi_setup;
683 	master->auto_runtime_pm = true;
684 	master->transfer_one_message = ti_qspi_start_transfer_one;
685 	master->dev.of_node = pdev->dev.of_node;
686 	master->bits_per_word_mask = SPI_BPW_MASK(32) | SPI_BPW_MASK(16) |
687 				     SPI_BPW_MASK(8);
688 	master->mem_ops = &ti_qspi_mem_ops;
689 
690 	if (!of_property_read_u32(np, "num-cs", &num_cs))
691 		master->num_chipselect = num_cs;
692 
693 	qspi = spi_master_get_devdata(master);
694 	qspi->master = master;
695 	qspi->dev = &pdev->dev;
696 	platform_set_drvdata(pdev, qspi);
697 
698 	r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "qspi_base");
699 	if (r == NULL) {
700 		r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
701 		if (r == NULL) {
702 			dev_err(&pdev->dev, "missing platform data\n");
703 			ret = -ENODEV;
704 			goto free_master;
705 		}
706 	}
707 
708 	res_mmap = platform_get_resource_byname(pdev,
709 			IORESOURCE_MEM, "qspi_mmap");
710 	if (res_mmap == NULL) {
711 		res_mmap = platform_get_resource(pdev, IORESOURCE_MEM, 1);
712 		if (res_mmap == NULL) {
713 			dev_err(&pdev->dev,
714 				"memory mapped resource not required\n");
715 		}
716 	}
717 
718 	if (res_mmap)
719 		qspi->mmap_size = resource_size(res_mmap);
720 
721 	irq = platform_get_irq(pdev, 0);
722 	if (irq < 0) {
723 		ret = irq;
724 		goto free_master;
725 	}
726 
727 	mutex_init(&qspi->list_lock);
728 
729 	qspi->base = devm_ioremap_resource(&pdev->dev, r);
730 	if (IS_ERR(qspi->base)) {
731 		ret = PTR_ERR(qspi->base);
732 		goto free_master;
733 	}
734 
735 
736 	if (of_property_read_bool(np, "syscon-chipselects")) {
737 		qspi->ctrl_base =
738 		syscon_regmap_lookup_by_phandle(np,
739 						"syscon-chipselects");
740 		if (IS_ERR(qspi->ctrl_base)) {
741 			ret = PTR_ERR(qspi->ctrl_base);
742 			goto free_master;
743 		}
744 		ret = of_property_read_u32_index(np,
745 						 "syscon-chipselects",
746 						 1, &qspi->ctrl_reg);
747 		if (ret) {
748 			dev_err(&pdev->dev,
749 				"couldn't get ctrl_mod reg index\n");
750 			goto free_master;
751 		}
752 	}
753 
754 	qspi->fclk = devm_clk_get(&pdev->dev, "fck");
755 	if (IS_ERR(qspi->fclk)) {
756 		ret = PTR_ERR(qspi->fclk);
757 		dev_err(&pdev->dev, "could not get clk: %d\n", ret);
758 	}
759 
760 	pm_runtime_use_autosuspend(&pdev->dev);
761 	pm_runtime_set_autosuspend_delay(&pdev->dev, QSPI_AUTOSUSPEND_TIMEOUT);
762 	pm_runtime_enable(&pdev->dev);
763 
764 	if (!of_property_read_u32(np, "spi-max-frequency", &max_freq))
765 		qspi->spi_max_frequency = max_freq;
766 
767 	dma_cap_zero(mask);
768 	dma_cap_set(DMA_MEMCPY, mask);
769 
770 	qspi->rx_chan = dma_request_chan_by_mask(&mask);
771 	if (IS_ERR(qspi->rx_chan)) {
772 		dev_err(qspi->dev,
773 			"No Rx DMA available, trying mmap mode\n");
774 		qspi->rx_chan = NULL;
775 		ret = 0;
776 		goto no_dma;
777 	}
778 	qspi->rx_bb_addr = dma_alloc_coherent(qspi->dev,
779 					      QSPI_DMA_BUFFER_SIZE,
780 					      &qspi->rx_bb_dma_addr,
781 					      GFP_KERNEL | GFP_DMA);
782 	if (!qspi->rx_bb_addr) {
783 		dev_err(qspi->dev,
784 			"dma_alloc_coherent failed, using PIO mode\n");
785 		dma_release_channel(qspi->rx_chan);
786 		goto no_dma;
787 	}
788 	master->dma_rx = qspi->rx_chan;
789 	init_completion(&qspi->transfer_complete);
790 	if (res_mmap)
791 		qspi->mmap_phys_base = (dma_addr_t)res_mmap->start;
792 
793 no_dma:
794 	if (!qspi->rx_chan && res_mmap) {
795 		qspi->mmap_base = devm_ioremap_resource(&pdev->dev, res_mmap);
796 		if (IS_ERR(qspi->mmap_base)) {
797 			dev_info(&pdev->dev,
798 				 "mmap failed with error %ld using PIO mode\n",
799 				 PTR_ERR(qspi->mmap_base));
800 			qspi->mmap_base = NULL;
801 			master->mem_ops = NULL;
802 		}
803 	}
804 	qspi->mmap_enabled = false;
805 	qspi->current_cs = -1;
806 
807 	ret = devm_spi_register_master(&pdev->dev, master);
808 	if (!ret)
809 		return 0;
810 
811 	pm_runtime_disable(&pdev->dev);
812 free_master:
813 	spi_master_put(master);
814 	return ret;
815 }
816 
817 static int ti_qspi_remove(struct platform_device *pdev)
818 {
819 	struct ti_qspi *qspi = platform_get_drvdata(pdev);
820 	int rc;
821 
822 	rc = spi_master_suspend(qspi->master);
823 	if (rc)
824 		return rc;
825 
826 	pm_runtime_put_sync(&pdev->dev);
827 	pm_runtime_disable(&pdev->dev);
828 
829 	if (qspi->rx_bb_addr)
830 		dma_free_coherent(qspi->dev, QSPI_DMA_BUFFER_SIZE,
831 				  qspi->rx_bb_addr,
832 				  qspi->rx_bb_dma_addr);
833 	if (qspi->rx_chan)
834 		dma_release_channel(qspi->rx_chan);
835 
836 	return 0;
837 }
838 
839 static const struct dev_pm_ops ti_qspi_pm_ops = {
840 	.runtime_resume = ti_qspi_runtime_resume,
841 };
842 
843 static struct platform_driver ti_qspi_driver = {
844 	.probe	= ti_qspi_probe,
845 	.remove = ti_qspi_remove,
846 	.driver = {
847 		.name	= "ti-qspi",
848 		.pm =   &ti_qspi_pm_ops,
849 		.of_match_table = ti_qspi_match,
850 	}
851 };
852 
853 module_platform_driver(ti_qspi_driver);
854 
855 MODULE_AUTHOR("Sourav Poddar <sourav.poddar@ti.com>");
856 MODULE_LICENSE("GPL v2");
857 MODULE_DESCRIPTION("TI QSPI controller driver");
858 MODULE_ALIAS("platform:ti-qspi");
859