xref: /linux/drivers/spi/spi-stm32-qspi.c (revision f2527d8f566a45fa00ee5abd04d1c9476d4d704f)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) STMicroelectronics 2018 - All Rights Reserved
4  * Author: Ludovic Barre <ludovic.barre@st.com> for STMicroelectronics.
5  */
6 #include <linux/bitfield.h>
7 #include <linux/clk.h>
8 #include <linux/dmaengine.h>
9 #include <linux/dma-mapping.h>
10 #include <linux/errno.h>
11 #include <linux/io.h>
12 #include <linux/iopoll.h>
13 #include <linux/interrupt.h>
14 #include <linux/module.h>
15 #include <linux/mutex.h>
16 #include <linux/of.h>
17 #include <linux/of_device.h>
18 #include <linux/of_gpio.h>
19 #include <linux/pinctrl/consumer.h>
20 #include <linux/pm_runtime.h>
21 #include <linux/platform_device.h>
22 #include <linux/reset.h>
23 #include <linux/sizes.h>
24 #include <linux/spi/spi-mem.h>
25 
26 #define QSPI_CR			0x00
27 #define CR_EN			BIT(0)
28 #define CR_ABORT		BIT(1)
29 #define CR_DMAEN		BIT(2)
30 #define CR_TCEN			BIT(3)
31 #define CR_SSHIFT		BIT(4)
32 #define CR_DFM			BIT(6)
33 #define CR_FSEL			BIT(7)
34 #define CR_FTHRES_SHIFT		8
35 #define CR_TEIE			BIT(16)
36 #define CR_TCIE			BIT(17)
37 #define CR_FTIE			BIT(18)
38 #define CR_SMIE			BIT(19)
39 #define CR_TOIE			BIT(20)
40 #define CR_APMS			BIT(22)
41 #define CR_PRESC_MASK		GENMASK(31, 24)
42 
43 #define QSPI_DCR		0x04
44 #define DCR_FSIZE_MASK		GENMASK(20, 16)
45 
46 #define QSPI_SR			0x08
47 #define SR_TEF			BIT(0)
48 #define SR_TCF			BIT(1)
49 #define SR_FTF			BIT(2)
50 #define SR_SMF			BIT(3)
51 #define SR_TOF			BIT(4)
52 #define SR_BUSY			BIT(5)
53 #define SR_FLEVEL_MASK		GENMASK(13, 8)
54 
55 #define QSPI_FCR		0x0c
56 #define FCR_CTEF		BIT(0)
57 #define FCR_CTCF		BIT(1)
58 #define FCR_CSMF		BIT(3)
59 
60 #define QSPI_DLR		0x10
61 
62 #define QSPI_CCR		0x14
63 #define CCR_INST_MASK		GENMASK(7, 0)
64 #define CCR_IMODE_MASK		GENMASK(9, 8)
65 #define CCR_ADMODE_MASK		GENMASK(11, 10)
66 #define CCR_ADSIZE_MASK		GENMASK(13, 12)
67 #define CCR_DCYC_MASK		GENMASK(22, 18)
68 #define CCR_DMODE_MASK		GENMASK(25, 24)
69 #define CCR_FMODE_MASK		GENMASK(27, 26)
70 #define CCR_FMODE_INDW		(0U << 26)
71 #define CCR_FMODE_INDR		(1U << 26)
72 #define CCR_FMODE_APM		(2U << 26)
73 #define CCR_FMODE_MM		(3U << 26)
74 #define CCR_BUSWIDTH_0		0x0
75 #define CCR_BUSWIDTH_1		0x1
76 #define CCR_BUSWIDTH_2		0x2
77 #define CCR_BUSWIDTH_4		0x3
78 
79 #define QSPI_AR			0x18
80 #define QSPI_ABR		0x1c
81 #define QSPI_DR			0x20
82 #define QSPI_PSMKR		0x24
83 #define QSPI_PSMAR		0x28
84 #define QSPI_PIR		0x2c
85 #define QSPI_LPTR		0x30
86 
87 #define STM32_QSPI_MAX_MMAP_SZ	SZ_256M
88 #define STM32_QSPI_MAX_NORCHIP	2
89 
90 #define STM32_FIFO_TIMEOUT_US 30000
91 #define STM32_BUSY_TIMEOUT_US 100000
92 #define STM32_ABT_TIMEOUT_US 100000
93 #define STM32_COMP_TIMEOUT_MS 1000
94 #define STM32_AUTOSUSPEND_DELAY -1
95 
96 struct stm32_qspi_flash {
97 	u32 cs;
98 	u32 presc;
99 };
100 
101 struct stm32_qspi {
102 	struct device *dev;
103 	struct spi_controller *ctrl;
104 	phys_addr_t phys_base;
105 	void __iomem *io_base;
106 	void __iomem *mm_base;
107 	resource_size_t mm_size;
108 	struct clk *clk;
109 	u32 clk_rate;
110 	struct stm32_qspi_flash flash[STM32_QSPI_MAX_NORCHIP];
111 	struct completion data_completion;
112 	struct completion match_completion;
113 	u32 fmode;
114 
115 	struct dma_chan *dma_chtx;
116 	struct dma_chan *dma_chrx;
117 	struct completion dma_completion;
118 
119 	u32 cr_reg;
120 	u32 dcr_reg;
121 	unsigned long status_timeout;
122 
123 	/*
124 	 * to protect device configuration, could be different between
125 	 * 2 flash access (bk1, bk2)
126 	 */
127 	struct mutex lock;
128 };
129 
130 static irqreturn_t stm32_qspi_irq(int irq, void *dev_id)
131 {
132 	struct stm32_qspi *qspi = (struct stm32_qspi *)dev_id;
133 	u32 cr, sr;
134 
135 	cr = readl_relaxed(qspi->io_base + QSPI_CR);
136 	sr = readl_relaxed(qspi->io_base + QSPI_SR);
137 
138 	if (cr & CR_SMIE && sr & SR_SMF) {
139 		/* disable irq */
140 		cr &= ~CR_SMIE;
141 		writel_relaxed(cr, qspi->io_base + QSPI_CR);
142 		complete(&qspi->match_completion);
143 
144 		return IRQ_HANDLED;
145 	}
146 
147 	if (sr & (SR_TEF | SR_TCF)) {
148 		/* disable irq */
149 		cr &= ~CR_TCIE & ~CR_TEIE;
150 		writel_relaxed(cr, qspi->io_base + QSPI_CR);
151 		complete(&qspi->data_completion);
152 	}
153 
154 	return IRQ_HANDLED;
155 }
156 
157 static void stm32_qspi_read_fifo(u8 *val, void __iomem *addr)
158 {
159 	*val = readb_relaxed(addr);
160 }
161 
162 static void stm32_qspi_write_fifo(u8 *val, void __iomem *addr)
163 {
164 	writeb_relaxed(*val, addr);
165 }
166 
167 static int stm32_qspi_tx_poll(struct stm32_qspi *qspi,
168 			      const struct spi_mem_op *op)
169 {
170 	void (*tx_fifo)(u8 *val, void __iomem *addr);
171 	u32 len = op->data.nbytes, sr;
172 	u8 *buf;
173 	int ret;
174 
175 	if (op->data.dir == SPI_MEM_DATA_IN) {
176 		tx_fifo = stm32_qspi_read_fifo;
177 		buf = op->data.buf.in;
178 
179 	} else {
180 		tx_fifo = stm32_qspi_write_fifo;
181 		buf = (u8 *)op->data.buf.out;
182 	}
183 
184 	while (len--) {
185 		ret = readl_relaxed_poll_timeout_atomic(qspi->io_base + QSPI_SR,
186 							sr, (sr & SR_FTF), 1,
187 							STM32_FIFO_TIMEOUT_US);
188 		if (ret) {
189 			dev_err(qspi->dev, "fifo timeout (len:%d stat:%#x)\n",
190 				len, sr);
191 			return ret;
192 		}
193 		tx_fifo(buf++, qspi->io_base + QSPI_DR);
194 	}
195 
196 	return 0;
197 }
198 
199 static int stm32_qspi_tx_mm(struct stm32_qspi *qspi,
200 			    const struct spi_mem_op *op)
201 {
202 	memcpy_fromio(op->data.buf.in, qspi->mm_base + op->addr.val,
203 		      op->data.nbytes);
204 	return 0;
205 }
206 
207 static void stm32_qspi_dma_callback(void *arg)
208 {
209 	struct completion *dma_completion = arg;
210 
211 	complete(dma_completion);
212 }
213 
214 static int stm32_qspi_tx_dma(struct stm32_qspi *qspi,
215 			     const struct spi_mem_op *op)
216 {
217 	struct dma_async_tx_descriptor *desc;
218 	enum dma_transfer_direction dma_dir;
219 	struct dma_chan *dma_ch;
220 	struct sg_table sgt;
221 	dma_cookie_t cookie;
222 	u32 cr, t_out;
223 	int err;
224 
225 	if (op->data.dir == SPI_MEM_DATA_IN) {
226 		dma_dir = DMA_DEV_TO_MEM;
227 		dma_ch = qspi->dma_chrx;
228 	} else {
229 		dma_dir = DMA_MEM_TO_DEV;
230 		dma_ch = qspi->dma_chtx;
231 	}
232 
233 	/*
234 	 * spi_map_buf return -EINVAL if the buffer is not DMA-able
235 	 * (DMA-able: in vmalloc | kmap | virt_addr_valid)
236 	 */
237 	err = spi_controller_dma_map_mem_op_data(qspi->ctrl, op, &sgt);
238 	if (err)
239 		return err;
240 
241 	desc = dmaengine_prep_slave_sg(dma_ch, sgt.sgl, sgt.nents,
242 				       dma_dir, DMA_PREP_INTERRUPT);
243 	if (!desc) {
244 		err = -ENOMEM;
245 		goto out_unmap;
246 	}
247 
248 	cr = readl_relaxed(qspi->io_base + QSPI_CR);
249 
250 	reinit_completion(&qspi->dma_completion);
251 	desc->callback = stm32_qspi_dma_callback;
252 	desc->callback_param = &qspi->dma_completion;
253 	cookie = dmaengine_submit(desc);
254 	err = dma_submit_error(cookie);
255 	if (err)
256 		goto out;
257 
258 	dma_async_issue_pending(dma_ch);
259 
260 	writel_relaxed(cr | CR_DMAEN, qspi->io_base + QSPI_CR);
261 
262 	t_out = sgt.nents * STM32_COMP_TIMEOUT_MS;
263 	if (!wait_for_completion_timeout(&qspi->dma_completion,
264 					 msecs_to_jiffies(t_out)))
265 		err = -ETIMEDOUT;
266 
267 	if (err)
268 		dmaengine_terminate_all(dma_ch);
269 
270 out:
271 	writel_relaxed(cr & ~CR_DMAEN, qspi->io_base + QSPI_CR);
272 out_unmap:
273 	spi_controller_dma_unmap_mem_op_data(qspi->ctrl, op, &sgt);
274 
275 	return err;
276 }
277 
278 static int stm32_qspi_tx(struct stm32_qspi *qspi, const struct spi_mem_op *op)
279 {
280 	if (!op->data.nbytes)
281 		return 0;
282 
283 	if (qspi->fmode == CCR_FMODE_MM)
284 		return stm32_qspi_tx_mm(qspi, op);
285 	else if (((op->data.dir == SPI_MEM_DATA_IN && qspi->dma_chrx) ||
286 		 (op->data.dir == SPI_MEM_DATA_OUT && qspi->dma_chtx)) &&
287 		  op->data.nbytes > 4)
288 		if (!stm32_qspi_tx_dma(qspi, op))
289 			return 0;
290 
291 	return stm32_qspi_tx_poll(qspi, op);
292 }
293 
294 static int stm32_qspi_wait_nobusy(struct stm32_qspi *qspi)
295 {
296 	u32 sr;
297 
298 	return readl_relaxed_poll_timeout_atomic(qspi->io_base + QSPI_SR, sr,
299 						 !(sr & SR_BUSY), 1,
300 						 STM32_BUSY_TIMEOUT_US);
301 }
302 
303 static int stm32_qspi_wait_cmd(struct stm32_qspi *qspi)
304 {
305 	u32 cr, sr;
306 	int err = 0;
307 
308 	if ((readl_relaxed(qspi->io_base + QSPI_SR) & SR_TCF) ||
309 	    qspi->fmode == CCR_FMODE_APM)
310 		goto out;
311 
312 	reinit_completion(&qspi->data_completion);
313 	cr = readl_relaxed(qspi->io_base + QSPI_CR);
314 	writel_relaxed(cr | CR_TCIE | CR_TEIE, qspi->io_base + QSPI_CR);
315 
316 	if (!wait_for_completion_timeout(&qspi->data_completion,
317 				msecs_to_jiffies(STM32_COMP_TIMEOUT_MS))) {
318 		err = -ETIMEDOUT;
319 	} else {
320 		sr = readl_relaxed(qspi->io_base + QSPI_SR);
321 		if (sr & SR_TEF)
322 			err = -EIO;
323 	}
324 
325 out:
326 	/* clear flags */
327 	writel_relaxed(FCR_CTCF | FCR_CTEF, qspi->io_base + QSPI_FCR);
328 	if (!err)
329 		err = stm32_qspi_wait_nobusy(qspi);
330 
331 	return err;
332 }
333 
334 static int stm32_qspi_wait_poll_status(struct stm32_qspi *qspi)
335 {
336 	u32 cr;
337 
338 	reinit_completion(&qspi->match_completion);
339 	cr = readl_relaxed(qspi->io_base + QSPI_CR);
340 	writel_relaxed(cr | CR_SMIE, qspi->io_base + QSPI_CR);
341 
342 	if (!wait_for_completion_timeout(&qspi->match_completion,
343 				msecs_to_jiffies(qspi->status_timeout)))
344 		return -ETIMEDOUT;
345 
346 	writel_relaxed(FCR_CSMF, qspi->io_base + QSPI_FCR);
347 
348 	return 0;
349 }
350 
351 static int stm32_qspi_get_mode(u8 buswidth)
352 {
353 	if (buswidth == 4)
354 		return CCR_BUSWIDTH_4;
355 
356 	return buswidth;
357 }
358 
359 static int stm32_qspi_send(struct spi_device *spi, const struct spi_mem_op *op)
360 {
361 	struct stm32_qspi *qspi = spi_controller_get_devdata(spi->master);
362 	struct stm32_qspi_flash *flash = &qspi->flash[spi->chip_select];
363 	u32 ccr, cr;
364 	int timeout, err = 0, err_poll_status = 0;
365 
366 	dev_dbg(qspi->dev, "cmd:%#x mode:%d.%d.%d.%d addr:%#llx len:%#x\n",
367 		op->cmd.opcode, op->cmd.buswidth, op->addr.buswidth,
368 		op->dummy.buswidth, op->data.buswidth,
369 		op->addr.val, op->data.nbytes);
370 
371 	cr = readl_relaxed(qspi->io_base + QSPI_CR);
372 	cr &= ~CR_PRESC_MASK & ~CR_FSEL;
373 	cr |= FIELD_PREP(CR_PRESC_MASK, flash->presc);
374 	cr |= FIELD_PREP(CR_FSEL, flash->cs);
375 	writel_relaxed(cr, qspi->io_base + QSPI_CR);
376 
377 	if (op->data.nbytes)
378 		writel_relaxed(op->data.nbytes - 1,
379 			       qspi->io_base + QSPI_DLR);
380 
381 	ccr = qspi->fmode;
382 	ccr |= FIELD_PREP(CCR_INST_MASK, op->cmd.opcode);
383 	ccr |= FIELD_PREP(CCR_IMODE_MASK,
384 			  stm32_qspi_get_mode(op->cmd.buswidth));
385 
386 	if (op->addr.nbytes) {
387 		ccr |= FIELD_PREP(CCR_ADMODE_MASK,
388 				  stm32_qspi_get_mode(op->addr.buswidth));
389 		ccr |= FIELD_PREP(CCR_ADSIZE_MASK, op->addr.nbytes - 1);
390 	}
391 
392 	if (op->dummy.nbytes)
393 		ccr |= FIELD_PREP(CCR_DCYC_MASK,
394 				  op->dummy.nbytes * 8 / op->dummy.buswidth);
395 
396 	if (op->data.nbytes) {
397 		ccr |= FIELD_PREP(CCR_DMODE_MASK,
398 				  stm32_qspi_get_mode(op->data.buswidth));
399 	}
400 
401 	writel_relaxed(ccr, qspi->io_base + QSPI_CCR);
402 
403 	if (op->addr.nbytes && qspi->fmode != CCR_FMODE_MM)
404 		writel_relaxed(op->addr.val, qspi->io_base + QSPI_AR);
405 
406 	if (qspi->fmode == CCR_FMODE_APM)
407 		err_poll_status = stm32_qspi_wait_poll_status(qspi);
408 
409 	err = stm32_qspi_tx(qspi, op);
410 
411 	/*
412 	 * Abort in:
413 	 * -error case
414 	 * -read memory map: prefetching must be stopped if we read the last
415 	 *  byte of device (device size - fifo size). like device size is not
416 	 *  knows, the prefetching is always stop.
417 	 */
418 	if (err || err_poll_status || qspi->fmode == CCR_FMODE_MM)
419 		goto abort;
420 
421 	/* wait end of tx in indirect mode */
422 	err = stm32_qspi_wait_cmd(qspi);
423 	if (err)
424 		goto abort;
425 
426 	return 0;
427 
428 abort:
429 	cr = readl_relaxed(qspi->io_base + QSPI_CR) | CR_ABORT;
430 	writel_relaxed(cr, qspi->io_base + QSPI_CR);
431 
432 	/* wait clear of abort bit by hw */
433 	timeout = readl_relaxed_poll_timeout_atomic(qspi->io_base + QSPI_CR,
434 						    cr, !(cr & CR_ABORT), 1,
435 						    STM32_ABT_TIMEOUT_US);
436 
437 	writel_relaxed(FCR_CTCF | FCR_CSMF, qspi->io_base + QSPI_FCR);
438 
439 	if (err || err_poll_status || timeout)
440 		dev_err(qspi->dev, "%s err:%d err_poll_status:%d abort timeout:%d\n",
441 			__func__, err, err_poll_status, timeout);
442 
443 	return err;
444 }
445 
446 static int stm32_qspi_poll_status(struct spi_mem *mem, const struct spi_mem_op *op,
447 				  u16 mask, u16 match,
448 				  unsigned long initial_delay_us,
449 				  unsigned long polling_rate_us,
450 				  unsigned long timeout_ms)
451 {
452 	struct stm32_qspi *qspi = spi_controller_get_devdata(mem->spi->master);
453 	int ret;
454 
455 	if (!spi_mem_supports_op(mem, op))
456 		return -EOPNOTSUPP;
457 
458 	ret = pm_runtime_resume_and_get(qspi->dev);
459 	if (ret < 0)
460 		return ret;
461 
462 	mutex_lock(&qspi->lock);
463 
464 	writel_relaxed(mask, qspi->io_base + QSPI_PSMKR);
465 	writel_relaxed(match, qspi->io_base + QSPI_PSMAR);
466 	qspi->fmode = CCR_FMODE_APM;
467 	qspi->status_timeout = timeout_ms;
468 
469 	ret = stm32_qspi_send(mem->spi, op);
470 	mutex_unlock(&qspi->lock);
471 
472 	pm_runtime_mark_last_busy(qspi->dev);
473 	pm_runtime_put_autosuspend(qspi->dev);
474 
475 	return ret;
476 }
477 
478 static int stm32_qspi_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
479 {
480 	struct stm32_qspi *qspi = spi_controller_get_devdata(mem->spi->master);
481 	int ret;
482 
483 	ret = pm_runtime_resume_and_get(qspi->dev);
484 	if (ret < 0)
485 		return ret;
486 
487 	mutex_lock(&qspi->lock);
488 	if (op->data.dir == SPI_MEM_DATA_IN && op->data.nbytes)
489 		qspi->fmode = CCR_FMODE_INDR;
490 	else
491 		qspi->fmode = CCR_FMODE_INDW;
492 
493 	ret = stm32_qspi_send(mem->spi, op);
494 	mutex_unlock(&qspi->lock);
495 
496 	pm_runtime_mark_last_busy(qspi->dev);
497 	pm_runtime_put_autosuspend(qspi->dev);
498 
499 	return ret;
500 }
501 
502 static int stm32_qspi_dirmap_create(struct spi_mem_dirmap_desc *desc)
503 {
504 	struct stm32_qspi *qspi = spi_controller_get_devdata(desc->mem->spi->master);
505 
506 	if (desc->info.op_tmpl.data.dir == SPI_MEM_DATA_OUT)
507 		return -EOPNOTSUPP;
508 
509 	/* should never happen, as mm_base == null is an error probe exit condition */
510 	if (!qspi->mm_base && desc->info.op_tmpl.data.dir == SPI_MEM_DATA_IN)
511 		return -EOPNOTSUPP;
512 
513 	if (!qspi->mm_size)
514 		return -EOPNOTSUPP;
515 
516 	return 0;
517 }
518 
519 static ssize_t stm32_qspi_dirmap_read(struct spi_mem_dirmap_desc *desc,
520 				      u64 offs, size_t len, void *buf)
521 {
522 	struct stm32_qspi *qspi = spi_controller_get_devdata(desc->mem->spi->master);
523 	struct spi_mem_op op;
524 	u32 addr_max;
525 	int ret;
526 
527 	ret = pm_runtime_resume_and_get(qspi->dev);
528 	if (ret < 0)
529 		return ret;
530 
531 	mutex_lock(&qspi->lock);
532 	/* make a local copy of desc op_tmpl and complete dirmap rdesc
533 	 * spi_mem_op template with offs, len and *buf in  order to get
534 	 * all needed transfer information into struct spi_mem_op
535 	 */
536 	memcpy(&op, &desc->info.op_tmpl, sizeof(struct spi_mem_op));
537 	dev_dbg(qspi->dev, "%s len = 0x%zx offs = 0x%llx buf = 0x%p\n", __func__, len, offs, buf);
538 
539 	op.data.nbytes = len;
540 	op.addr.val = desc->info.offset + offs;
541 	op.data.buf.in = buf;
542 
543 	addr_max = op.addr.val + op.data.nbytes + 1;
544 	if (addr_max < qspi->mm_size && op.addr.buswidth)
545 		qspi->fmode = CCR_FMODE_MM;
546 	else
547 		qspi->fmode = CCR_FMODE_INDR;
548 
549 	ret = stm32_qspi_send(desc->mem->spi, &op);
550 	mutex_unlock(&qspi->lock);
551 
552 	pm_runtime_mark_last_busy(qspi->dev);
553 	pm_runtime_put_autosuspend(qspi->dev);
554 
555 	return ret ?: len;
556 }
557 
558 static int stm32_qspi_transfer_one_message(struct spi_controller *ctrl,
559 					   struct spi_message *msg)
560 {
561 	struct stm32_qspi *qspi = spi_controller_get_devdata(ctrl);
562 	struct spi_transfer *transfer;
563 	struct spi_device *spi = msg->spi;
564 	struct spi_mem_op op;
565 	int ret = 0;
566 
567 	if (!spi->cs_gpiod)
568 		return -EOPNOTSUPP;
569 
570 	ret = pm_runtime_resume_and_get(qspi->dev);
571 	if (ret < 0)
572 		return ret;
573 
574 	mutex_lock(&qspi->lock);
575 
576 	gpiod_set_value_cansleep(spi->cs_gpiod, true);
577 
578 	list_for_each_entry(transfer, &msg->transfers, transfer_list) {
579 		u8 dummy_bytes = 0;
580 
581 		memset(&op, 0, sizeof(op));
582 
583 		dev_dbg(qspi->dev, "tx_buf:%p tx_nbits:%d rx_buf:%p rx_nbits:%d len:%d dummy_data:%d\n",
584 			transfer->tx_buf, transfer->tx_nbits,
585 			transfer->rx_buf, transfer->rx_nbits,
586 			transfer->len, transfer->dummy_data);
587 
588 		/*
589 		 * QSPI hardware supports dummy bytes transfer.
590 		 * If current transfer is dummy byte, merge it with the next
591 		 * transfer in order to take into account QSPI block constraint
592 		 */
593 		if (transfer->dummy_data) {
594 			op.dummy.buswidth = transfer->tx_nbits;
595 			op.dummy.nbytes = transfer->len;
596 			dummy_bytes = transfer->len;
597 
598 			/* if happens, means that message is not correctly built */
599 			if (list_is_last(&transfer->transfer_list, &msg->transfers)) {
600 				ret = -EINVAL;
601 				goto end_of_transfer;
602 			}
603 
604 			transfer = list_next_entry(transfer, transfer_list);
605 		}
606 
607 		op.data.nbytes = transfer->len;
608 
609 		if (transfer->rx_buf) {
610 			qspi->fmode = CCR_FMODE_INDR;
611 			op.data.buswidth = transfer->rx_nbits;
612 			op.data.dir = SPI_MEM_DATA_IN;
613 			op.data.buf.in = transfer->rx_buf;
614 		} else {
615 			qspi->fmode = CCR_FMODE_INDW;
616 			op.data.buswidth = transfer->tx_nbits;
617 			op.data.dir = SPI_MEM_DATA_OUT;
618 			op.data.buf.out = transfer->tx_buf;
619 		}
620 
621 		ret = stm32_qspi_send(spi, &op);
622 		if (ret)
623 			goto end_of_transfer;
624 
625 		msg->actual_length += transfer->len + dummy_bytes;
626 	}
627 
628 end_of_transfer:
629 	gpiod_set_value_cansleep(spi->cs_gpiod, false);
630 
631 	mutex_unlock(&qspi->lock);
632 
633 	msg->status = ret;
634 	spi_finalize_current_message(ctrl);
635 
636 	pm_runtime_mark_last_busy(qspi->dev);
637 	pm_runtime_put_autosuspend(qspi->dev);
638 
639 	return ret;
640 }
641 
642 static int stm32_qspi_setup(struct spi_device *spi)
643 {
644 	struct spi_controller *ctrl = spi->master;
645 	struct stm32_qspi *qspi = spi_controller_get_devdata(ctrl);
646 	struct stm32_qspi_flash *flash;
647 	u32 presc, mode;
648 	int ret;
649 
650 	if (ctrl->busy)
651 		return -EBUSY;
652 
653 	if (!spi->max_speed_hz)
654 		return -EINVAL;
655 
656 	mode = spi->mode & (SPI_TX_OCTAL | SPI_RX_OCTAL);
657 	if ((mode == SPI_TX_OCTAL || mode == SPI_RX_OCTAL) ||
658 	    ((mode == (SPI_TX_OCTAL | SPI_RX_OCTAL)) &&
659 	    gpiod_count(qspi->dev, "cs") == -ENOENT)) {
660 		dev_err(qspi->dev, "spi-rx-bus-width\\/spi-tx-bus-width\\/cs-gpios\n");
661 		dev_err(qspi->dev, "configuration not supported\n");
662 
663 		return -EINVAL;
664 	}
665 
666 	ret = pm_runtime_resume_and_get(qspi->dev);
667 	if (ret < 0)
668 		return ret;
669 
670 	presc = DIV_ROUND_UP(qspi->clk_rate, spi->max_speed_hz) - 1;
671 
672 	flash = &qspi->flash[spi->chip_select];
673 	flash->cs = spi->chip_select;
674 	flash->presc = presc;
675 
676 	mutex_lock(&qspi->lock);
677 	qspi->cr_reg = CR_APMS | 3 << CR_FTHRES_SHIFT | CR_SSHIFT | CR_EN;
678 
679 	/*
680 	 * Dual flash mode is only enable in case SPI_TX_OCTAL and SPI_TX_OCTAL
681 	 * are both set in spi->mode and "cs-gpios" properties is found in DT
682 	 */
683 	if (mode == (SPI_TX_OCTAL | SPI_RX_OCTAL)) {
684 		qspi->cr_reg |= CR_DFM;
685 		dev_dbg(qspi->dev, "Dual flash mode enable");
686 	}
687 
688 	writel_relaxed(qspi->cr_reg, qspi->io_base + QSPI_CR);
689 
690 	/* set dcr fsize to max address */
691 	qspi->dcr_reg = DCR_FSIZE_MASK;
692 	writel_relaxed(qspi->dcr_reg, qspi->io_base + QSPI_DCR);
693 	mutex_unlock(&qspi->lock);
694 
695 	pm_runtime_mark_last_busy(qspi->dev);
696 	pm_runtime_put_autosuspend(qspi->dev);
697 
698 	return 0;
699 }
700 
701 static int stm32_qspi_dma_setup(struct stm32_qspi *qspi)
702 {
703 	struct dma_slave_config dma_cfg;
704 	struct device *dev = qspi->dev;
705 	int ret = 0;
706 
707 	memset(&dma_cfg, 0, sizeof(dma_cfg));
708 
709 	dma_cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
710 	dma_cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
711 	dma_cfg.src_addr = qspi->phys_base + QSPI_DR;
712 	dma_cfg.dst_addr = qspi->phys_base + QSPI_DR;
713 	dma_cfg.src_maxburst = 4;
714 	dma_cfg.dst_maxburst = 4;
715 
716 	qspi->dma_chrx = dma_request_chan(dev, "rx");
717 	if (IS_ERR(qspi->dma_chrx)) {
718 		ret = PTR_ERR(qspi->dma_chrx);
719 		qspi->dma_chrx = NULL;
720 		if (ret == -EPROBE_DEFER)
721 			goto out;
722 	} else {
723 		if (dmaengine_slave_config(qspi->dma_chrx, &dma_cfg)) {
724 			dev_err(dev, "dma rx config failed\n");
725 			dma_release_channel(qspi->dma_chrx);
726 			qspi->dma_chrx = NULL;
727 		}
728 	}
729 
730 	qspi->dma_chtx = dma_request_chan(dev, "tx");
731 	if (IS_ERR(qspi->dma_chtx)) {
732 		ret = PTR_ERR(qspi->dma_chtx);
733 		qspi->dma_chtx = NULL;
734 	} else {
735 		if (dmaengine_slave_config(qspi->dma_chtx, &dma_cfg)) {
736 			dev_err(dev, "dma tx config failed\n");
737 			dma_release_channel(qspi->dma_chtx);
738 			qspi->dma_chtx = NULL;
739 		}
740 	}
741 
742 out:
743 	init_completion(&qspi->dma_completion);
744 
745 	if (ret != -EPROBE_DEFER)
746 		ret = 0;
747 
748 	return ret;
749 }
750 
751 static void stm32_qspi_dma_free(struct stm32_qspi *qspi)
752 {
753 	if (qspi->dma_chtx)
754 		dma_release_channel(qspi->dma_chtx);
755 	if (qspi->dma_chrx)
756 		dma_release_channel(qspi->dma_chrx);
757 }
758 
759 /*
760  * no special host constraint, so use default spi_mem_default_supports_op
761  * to check supported mode.
762  */
763 static const struct spi_controller_mem_ops stm32_qspi_mem_ops = {
764 	.exec_op	= stm32_qspi_exec_op,
765 	.dirmap_create	= stm32_qspi_dirmap_create,
766 	.dirmap_read	= stm32_qspi_dirmap_read,
767 	.poll_status	= stm32_qspi_poll_status,
768 };
769 
770 static int stm32_qspi_probe(struct platform_device *pdev)
771 {
772 	struct device *dev = &pdev->dev;
773 	struct spi_controller *ctrl;
774 	struct reset_control *rstc;
775 	struct stm32_qspi *qspi;
776 	struct resource *res;
777 	int ret, irq;
778 
779 	ctrl = devm_spi_alloc_master(dev, sizeof(*qspi));
780 	if (!ctrl)
781 		return -ENOMEM;
782 
783 	qspi = spi_controller_get_devdata(ctrl);
784 	qspi->ctrl = ctrl;
785 
786 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "qspi");
787 	qspi->io_base = devm_ioremap_resource(dev, res);
788 	if (IS_ERR(qspi->io_base))
789 		return PTR_ERR(qspi->io_base);
790 
791 	qspi->phys_base = res->start;
792 
793 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "qspi_mm");
794 	qspi->mm_base = devm_ioremap_resource(dev, res);
795 	if (IS_ERR(qspi->mm_base))
796 		return PTR_ERR(qspi->mm_base);
797 
798 	qspi->mm_size = resource_size(res);
799 	if (qspi->mm_size > STM32_QSPI_MAX_MMAP_SZ)
800 		return -EINVAL;
801 
802 	irq = platform_get_irq(pdev, 0);
803 	if (irq < 0)
804 		return irq;
805 
806 	ret = devm_request_irq(dev, irq, stm32_qspi_irq, 0,
807 			       dev_name(dev), qspi);
808 	if (ret) {
809 		dev_err(dev, "failed to request irq\n");
810 		return ret;
811 	}
812 
813 	init_completion(&qspi->data_completion);
814 	init_completion(&qspi->match_completion);
815 
816 	qspi->clk = devm_clk_get(dev, NULL);
817 	if (IS_ERR(qspi->clk))
818 		return PTR_ERR(qspi->clk);
819 
820 	qspi->clk_rate = clk_get_rate(qspi->clk);
821 	if (!qspi->clk_rate)
822 		return -EINVAL;
823 
824 	ret = clk_prepare_enable(qspi->clk);
825 	if (ret) {
826 		dev_err(dev, "can not enable the clock\n");
827 		return ret;
828 	}
829 
830 	rstc = devm_reset_control_get_exclusive(dev, NULL);
831 	if (IS_ERR(rstc)) {
832 		ret = PTR_ERR(rstc);
833 		if (ret == -EPROBE_DEFER)
834 			goto err_clk_disable;
835 	} else {
836 		reset_control_assert(rstc);
837 		udelay(2);
838 		reset_control_deassert(rstc);
839 	}
840 
841 	qspi->dev = dev;
842 	platform_set_drvdata(pdev, qspi);
843 	ret = stm32_qspi_dma_setup(qspi);
844 	if (ret)
845 		goto err_dma_free;
846 
847 	mutex_init(&qspi->lock);
848 
849 	ctrl->mode_bits = SPI_RX_DUAL | SPI_RX_QUAD | SPI_TX_OCTAL
850 		| SPI_TX_DUAL | SPI_TX_QUAD | SPI_RX_OCTAL;
851 	ctrl->setup = stm32_qspi_setup;
852 	ctrl->bus_num = -1;
853 	ctrl->mem_ops = &stm32_qspi_mem_ops;
854 	ctrl->use_gpio_descriptors = true;
855 	ctrl->transfer_one_message = stm32_qspi_transfer_one_message;
856 	ctrl->num_chipselect = STM32_QSPI_MAX_NORCHIP;
857 	ctrl->dev.of_node = dev->of_node;
858 
859 	pm_runtime_set_autosuspend_delay(dev, STM32_AUTOSUSPEND_DELAY);
860 	pm_runtime_use_autosuspend(dev);
861 	pm_runtime_set_active(dev);
862 	pm_runtime_enable(dev);
863 	pm_runtime_get_noresume(dev);
864 
865 	ret = spi_register_master(ctrl);
866 	if (ret)
867 		goto err_pm_runtime_free;
868 
869 	pm_runtime_mark_last_busy(dev);
870 	pm_runtime_put_autosuspend(dev);
871 
872 	return 0;
873 
874 err_pm_runtime_free:
875 	pm_runtime_get_sync(qspi->dev);
876 	/* disable qspi */
877 	writel_relaxed(0, qspi->io_base + QSPI_CR);
878 	mutex_destroy(&qspi->lock);
879 	pm_runtime_put_noidle(qspi->dev);
880 	pm_runtime_disable(qspi->dev);
881 	pm_runtime_set_suspended(qspi->dev);
882 	pm_runtime_dont_use_autosuspend(qspi->dev);
883 err_dma_free:
884 	stm32_qspi_dma_free(qspi);
885 err_clk_disable:
886 	clk_disable_unprepare(qspi->clk);
887 
888 	return ret;
889 }
890 
891 static int stm32_qspi_remove(struct platform_device *pdev)
892 {
893 	struct stm32_qspi *qspi = platform_get_drvdata(pdev);
894 
895 	pm_runtime_get_sync(qspi->dev);
896 	spi_unregister_master(qspi->ctrl);
897 	/* disable qspi */
898 	writel_relaxed(0, qspi->io_base + QSPI_CR);
899 	stm32_qspi_dma_free(qspi);
900 	mutex_destroy(&qspi->lock);
901 	pm_runtime_put_noidle(qspi->dev);
902 	pm_runtime_disable(qspi->dev);
903 	pm_runtime_set_suspended(qspi->dev);
904 	pm_runtime_dont_use_autosuspend(qspi->dev);
905 	clk_disable_unprepare(qspi->clk);
906 
907 	return 0;
908 }
909 
910 static int __maybe_unused stm32_qspi_runtime_suspend(struct device *dev)
911 {
912 	struct stm32_qspi *qspi = dev_get_drvdata(dev);
913 
914 	clk_disable_unprepare(qspi->clk);
915 
916 	return 0;
917 }
918 
919 static int __maybe_unused stm32_qspi_runtime_resume(struct device *dev)
920 {
921 	struct stm32_qspi *qspi = dev_get_drvdata(dev);
922 
923 	return clk_prepare_enable(qspi->clk);
924 }
925 
926 static int __maybe_unused stm32_qspi_suspend(struct device *dev)
927 {
928 	pinctrl_pm_select_sleep_state(dev);
929 
930 	return pm_runtime_force_suspend(dev);
931 }
932 
933 static int __maybe_unused stm32_qspi_resume(struct device *dev)
934 {
935 	struct stm32_qspi *qspi = dev_get_drvdata(dev);
936 	int ret;
937 
938 	ret = pm_runtime_force_resume(dev);
939 	if (ret < 0)
940 		return ret;
941 
942 	pinctrl_pm_select_default_state(dev);
943 
944 	ret = pm_runtime_resume_and_get(dev);
945 	if (ret < 0)
946 		return ret;
947 
948 	writel_relaxed(qspi->cr_reg, qspi->io_base + QSPI_CR);
949 	writel_relaxed(qspi->dcr_reg, qspi->io_base + QSPI_DCR);
950 
951 	pm_runtime_mark_last_busy(dev);
952 	pm_runtime_put_autosuspend(dev);
953 
954 	return 0;
955 }
956 
957 static const struct dev_pm_ops stm32_qspi_pm_ops = {
958 	SET_RUNTIME_PM_OPS(stm32_qspi_runtime_suspend,
959 			   stm32_qspi_runtime_resume, NULL)
960 	SET_SYSTEM_SLEEP_PM_OPS(stm32_qspi_suspend, stm32_qspi_resume)
961 };
962 
963 static const struct of_device_id stm32_qspi_match[] = {
964 	{.compatible = "st,stm32f469-qspi"},
965 	{}
966 };
967 MODULE_DEVICE_TABLE(of, stm32_qspi_match);
968 
969 static struct platform_driver stm32_qspi_driver = {
970 	.probe	= stm32_qspi_probe,
971 	.remove	= stm32_qspi_remove,
972 	.driver	= {
973 		.name = "stm32-qspi",
974 		.of_match_table = stm32_qspi_match,
975 		.pm = &stm32_qspi_pm_ops,
976 	},
977 };
978 module_platform_driver(stm32_qspi_driver);
979 
980 MODULE_AUTHOR("Ludovic Barre <ludovic.barre@st.com>");
981 MODULE_DESCRIPTION("STMicroelectronics STM32 quad spi driver");
982 MODULE_LICENSE("GPL v2");
983