xref: /openbmc/linux/drivers/spi/spi-stm32-qspi.c (revision 8e7ae8ba)
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/pinctrl/consumer.h>
19 #include <linux/pm_runtime.h>
20 #include <linux/platform_device.h>
21 #include <linux/reset.h>
22 #include <linux/sizes.h>
23 #include <linux/spi/spi-mem.h>
24 
25 #define QSPI_CR			0x00
26 #define CR_EN			BIT(0)
27 #define CR_ABORT		BIT(1)
28 #define CR_DMAEN		BIT(2)
29 #define CR_TCEN			BIT(3)
30 #define CR_SSHIFT		BIT(4)
31 #define CR_DFM			BIT(6)
32 #define CR_FSEL			BIT(7)
33 #define CR_FTHRES_SHIFT		8
34 #define CR_TEIE			BIT(16)
35 #define CR_TCIE			BIT(17)
36 #define CR_FTIE			BIT(18)
37 #define CR_SMIE			BIT(19)
38 #define CR_TOIE			BIT(20)
39 #define CR_APMS			BIT(22)
40 #define CR_PRESC_MASK		GENMASK(31, 24)
41 
42 #define QSPI_DCR		0x04
43 #define DCR_FSIZE_MASK		GENMASK(20, 16)
44 
45 #define QSPI_SR			0x08
46 #define SR_TEF			BIT(0)
47 #define SR_TCF			BIT(1)
48 #define SR_FTF			BIT(2)
49 #define SR_SMF			BIT(3)
50 #define SR_TOF			BIT(4)
51 #define SR_BUSY			BIT(5)
52 #define SR_FLEVEL_MASK		GENMASK(13, 8)
53 
54 #define QSPI_FCR		0x0c
55 #define FCR_CTEF		BIT(0)
56 #define FCR_CTCF		BIT(1)
57 #define FCR_CSMF		BIT(3)
58 
59 #define QSPI_DLR		0x10
60 
61 #define QSPI_CCR		0x14
62 #define CCR_INST_MASK		GENMASK(7, 0)
63 #define CCR_IMODE_MASK		GENMASK(9, 8)
64 #define CCR_ADMODE_MASK		GENMASK(11, 10)
65 #define CCR_ADSIZE_MASK		GENMASK(13, 12)
66 #define CCR_DCYC_MASK		GENMASK(22, 18)
67 #define CCR_DMODE_MASK		GENMASK(25, 24)
68 #define CCR_FMODE_MASK		GENMASK(27, 26)
69 #define CCR_FMODE_INDW		(0U << 26)
70 #define CCR_FMODE_INDR		(1U << 26)
71 #define CCR_FMODE_APM		(2U << 26)
72 #define CCR_FMODE_MM		(3U << 26)
73 #define CCR_BUSWIDTH_0		0x0
74 #define CCR_BUSWIDTH_1		0x1
75 #define CCR_BUSWIDTH_2		0x2
76 #define CCR_BUSWIDTH_4		0x3
77 
78 #define QSPI_AR			0x18
79 #define QSPI_ABR		0x1c
80 #define QSPI_DR			0x20
81 #define QSPI_PSMKR		0x24
82 #define QSPI_PSMAR		0x28
83 #define QSPI_PIR		0x2c
84 #define QSPI_LPTR		0x30
85 
86 #define STM32_QSPI_MAX_MMAP_SZ	SZ_256M
87 #define STM32_QSPI_MAX_NORCHIP	2
88 
89 #define STM32_FIFO_TIMEOUT_US 30000
90 #define STM32_BUSY_TIMEOUT_US 100000
91 #define STM32_ABT_TIMEOUT_US 100000
92 #define STM32_COMP_TIMEOUT_MS 1000
93 #define STM32_AUTOSUSPEND_DELAY -1
94 
95 struct stm32_qspi_flash {
96 	u32 cs;
97 	u32 presc;
98 };
99 
100 struct stm32_qspi {
101 	struct device *dev;
102 	struct spi_controller *ctrl;
103 	phys_addr_t phys_base;
104 	void __iomem *io_base;
105 	void __iomem *mm_base;
106 	resource_size_t mm_size;
107 	struct clk *clk;
108 	u32 clk_rate;
109 	struct stm32_qspi_flash flash[STM32_QSPI_MAX_NORCHIP];
110 	struct completion data_completion;
111 	struct completion match_completion;
112 	u32 fmode;
113 
114 	struct dma_chan *dma_chtx;
115 	struct dma_chan *dma_chrx;
116 	struct completion dma_completion;
117 
118 	u32 cr_reg;
119 	u32 dcr_reg;
120 	unsigned long status_timeout;
121 
122 	/*
123 	 * to protect device configuration, could be different between
124 	 * 2 flash access (bk1, bk2)
125 	 */
126 	struct mutex lock;
127 };
128 
129 static irqreturn_t stm32_qspi_irq(int irq, void *dev_id)
130 {
131 	struct stm32_qspi *qspi = (struct stm32_qspi *)dev_id;
132 	u32 cr, sr;
133 
134 	cr = readl_relaxed(qspi->io_base + QSPI_CR);
135 	sr = readl_relaxed(qspi->io_base + QSPI_SR);
136 
137 	if (cr & CR_SMIE && sr & SR_SMF) {
138 		/* disable irq */
139 		cr &= ~CR_SMIE;
140 		writel_relaxed(cr, qspi->io_base + QSPI_CR);
141 		complete(&qspi->match_completion);
142 
143 		return IRQ_HANDLED;
144 	}
145 
146 	if (sr & (SR_TEF | SR_TCF)) {
147 		/* disable irq */
148 		cr &= ~CR_TCIE & ~CR_TEIE;
149 		writel_relaxed(cr, qspi->io_base + QSPI_CR);
150 		complete(&qspi->data_completion);
151 	}
152 
153 	return IRQ_HANDLED;
154 }
155 
156 static void stm32_qspi_read_fifo(u8 *val, void __iomem *addr)
157 {
158 	*val = readb_relaxed(addr);
159 }
160 
161 static void stm32_qspi_write_fifo(u8 *val, void __iomem *addr)
162 {
163 	writeb_relaxed(*val, addr);
164 }
165 
166 static int stm32_qspi_tx_poll(struct stm32_qspi *qspi,
167 			      const struct spi_mem_op *op)
168 {
169 	void (*tx_fifo)(u8 *val, void __iomem *addr);
170 	u32 len = op->data.nbytes, sr;
171 	u8 *buf;
172 	int ret;
173 
174 	if (op->data.dir == SPI_MEM_DATA_IN) {
175 		tx_fifo = stm32_qspi_read_fifo;
176 		buf = op->data.buf.in;
177 
178 	} else {
179 		tx_fifo = stm32_qspi_write_fifo;
180 		buf = (u8 *)op->data.buf.out;
181 	}
182 
183 	while (len--) {
184 		ret = readl_relaxed_poll_timeout_atomic(qspi->io_base + QSPI_SR,
185 							sr, (sr & SR_FTF), 1,
186 							STM32_FIFO_TIMEOUT_US);
187 		if (ret) {
188 			dev_err(qspi->dev, "fifo timeout (len:%d stat:%#x)\n",
189 				len, sr);
190 			return ret;
191 		}
192 		tx_fifo(buf++, qspi->io_base + QSPI_DR);
193 	}
194 
195 	return 0;
196 }
197 
198 static int stm32_qspi_tx_mm(struct stm32_qspi *qspi,
199 			    const struct spi_mem_op *op)
200 {
201 	memcpy_fromio(op->data.buf.in, qspi->mm_base + op->addr.val,
202 		      op->data.nbytes);
203 	return 0;
204 }
205 
206 static void stm32_qspi_dma_callback(void *arg)
207 {
208 	struct completion *dma_completion = arg;
209 
210 	complete(dma_completion);
211 }
212 
213 static int stm32_qspi_tx_dma(struct stm32_qspi *qspi,
214 			     const struct spi_mem_op *op)
215 {
216 	struct dma_async_tx_descriptor *desc;
217 	enum dma_transfer_direction dma_dir;
218 	struct dma_chan *dma_ch;
219 	struct sg_table sgt;
220 	dma_cookie_t cookie;
221 	u32 cr, t_out;
222 	int err;
223 
224 	if (op->data.dir == SPI_MEM_DATA_IN) {
225 		dma_dir = DMA_DEV_TO_MEM;
226 		dma_ch = qspi->dma_chrx;
227 	} else {
228 		dma_dir = DMA_MEM_TO_DEV;
229 		dma_ch = qspi->dma_chtx;
230 	}
231 
232 	/*
233 	 * spi_map_buf return -EINVAL if the buffer is not DMA-able
234 	 * (DMA-able: in vmalloc | kmap | virt_addr_valid)
235 	 */
236 	err = spi_controller_dma_map_mem_op_data(qspi->ctrl, op, &sgt);
237 	if (err)
238 		return err;
239 
240 	desc = dmaengine_prep_slave_sg(dma_ch, sgt.sgl, sgt.nents,
241 				       dma_dir, DMA_PREP_INTERRUPT);
242 	if (!desc) {
243 		err = -ENOMEM;
244 		goto out_unmap;
245 	}
246 
247 	cr = readl_relaxed(qspi->io_base + QSPI_CR);
248 
249 	reinit_completion(&qspi->dma_completion);
250 	desc->callback = stm32_qspi_dma_callback;
251 	desc->callback_param = &qspi->dma_completion;
252 	cookie = dmaengine_submit(desc);
253 	err = dma_submit_error(cookie);
254 	if (err)
255 		goto out;
256 
257 	dma_async_issue_pending(dma_ch);
258 
259 	writel_relaxed(cr | CR_DMAEN, qspi->io_base + QSPI_CR);
260 
261 	t_out = sgt.nents * STM32_COMP_TIMEOUT_MS;
262 	if (!wait_for_completion_timeout(&qspi->dma_completion,
263 					 msecs_to_jiffies(t_out)))
264 		err = -ETIMEDOUT;
265 
266 	if (err)
267 		dmaengine_terminate_all(dma_ch);
268 
269 out:
270 	writel_relaxed(cr & ~CR_DMAEN, qspi->io_base + QSPI_CR);
271 out_unmap:
272 	spi_controller_dma_unmap_mem_op_data(qspi->ctrl, op, &sgt);
273 
274 	return err;
275 }
276 
277 static int stm32_qspi_tx(struct stm32_qspi *qspi, const struct spi_mem_op *op)
278 {
279 	if (!op->data.nbytes)
280 		return 0;
281 
282 	if (qspi->fmode == CCR_FMODE_MM)
283 		return stm32_qspi_tx_mm(qspi, op);
284 	else if (((op->data.dir == SPI_MEM_DATA_IN && qspi->dma_chrx) ||
285 		 (op->data.dir == SPI_MEM_DATA_OUT && qspi->dma_chtx)) &&
286 		  op->data.nbytes > 4)
287 		if (!stm32_qspi_tx_dma(qspi, op))
288 			return 0;
289 
290 	return stm32_qspi_tx_poll(qspi, op);
291 }
292 
293 static int stm32_qspi_wait_nobusy(struct stm32_qspi *qspi)
294 {
295 	u32 sr;
296 
297 	return readl_relaxed_poll_timeout_atomic(qspi->io_base + QSPI_SR, sr,
298 						 !(sr & SR_BUSY), 1,
299 						 STM32_BUSY_TIMEOUT_US);
300 }
301 
302 static int stm32_qspi_wait_cmd(struct stm32_qspi *qspi,
303 			       const struct spi_mem_op *op)
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 				       const struct spi_mem_op *op)
336 {
337 	u32 cr;
338 
339 	reinit_completion(&qspi->match_completion);
340 	cr = readl_relaxed(qspi->io_base + QSPI_CR);
341 	writel_relaxed(cr | CR_SMIE, qspi->io_base + QSPI_CR);
342 
343 	if (!wait_for_completion_timeout(&qspi->match_completion,
344 				msecs_to_jiffies(qspi->status_timeout)))
345 		return -ETIMEDOUT;
346 
347 	writel_relaxed(FCR_CSMF, qspi->io_base + QSPI_FCR);
348 
349 	return 0;
350 }
351 
352 static int stm32_qspi_get_mode(struct stm32_qspi *qspi, u8 buswidth)
353 {
354 	if (buswidth == 4)
355 		return CCR_BUSWIDTH_4;
356 
357 	return buswidth;
358 }
359 
360 static int stm32_qspi_send(struct spi_mem *mem, const struct spi_mem_op *op)
361 {
362 	struct stm32_qspi *qspi = spi_controller_get_devdata(mem->spi->master);
363 	struct stm32_qspi_flash *flash = &qspi->flash[mem->spi->chip_select];
364 	u32 ccr, cr;
365 	int timeout, err = 0, err_poll_status = 0;
366 
367 	dev_dbg(qspi->dev, "cmd:%#x mode:%d.%d.%d.%d addr:%#llx len:%#x\n",
368 		op->cmd.opcode, op->cmd.buswidth, op->addr.buswidth,
369 		op->dummy.buswidth, op->data.buswidth,
370 		op->addr.val, op->data.nbytes);
371 
372 	cr = readl_relaxed(qspi->io_base + QSPI_CR);
373 	cr &= ~CR_PRESC_MASK & ~CR_FSEL;
374 	cr |= FIELD_PREP(CR_PRESC_MASK, flash->presc);
375 	cr |= FIELD_PREP(CR_FSEL, flash->cs);
376 	writel_relaxed(cr, qspi->io_base + QSPI_CR);
377 
378 	if (op->data.nbytes)
379 		writel_relaxed(op->data.nbytes - 1,
380 			       qspi->io_base + QSPI_DLR);
381 
382 	ccr = qspi->fmode;
383 	ccr |= FIELD_PREP(CCR_INST_MASK, op->cmd.opcode);
384 	ccr |= FIELD_PREP(CCR_IMODE_MASK,
385 			  stm32_qspi_get_mode(qspi, op->cmd.buswidth));
386 
387 	if (op->addr.nbytes) {
388 		ccr |= FIELD_PREP(CCR_ADMODE_MASK,
389 				  stm32_qspi_get_mode(qspi, op->addr.buswidth));
390 		ccr |= FIELD_PREP(CCR_ADSIZE_MASK, op->addr.nbytes - 1);
391 	}
392 
393 	if (op->dummy.nbytes)
394 		ccr |= FIELD_PREP(CCR_DCYC_MASK,
395 				  op->dummy.nbytes * 8 / op->dummy.buswidth);
396 
397 	if (op->data.nbytes) {
398 		ccr |= FIELD_PREP(CCR_DMODE_MASK,
399 				  stm32_qspi_get_mode(qspi, op->data.buswidth));
400 	}
401 
402 	writel_relaxed(ccr, qspi->io_base + QSPI_CCR);
403 
404 	if (op->addr.nbytes && qspi->fmode != CCR_FMODE_MM)
405 		writel_relaxed(op->addr.val, qspi->io_base + QSPI_AR);
406 
407 	if (qspi->fmode == CCR_FMODE_APM)
408 		err_poll_status = stm32_qspi_wait_poll_status(qspi, op);
409 
410 	err = stm32_qspi_tx(qspi, op);
411 
412 	/*
413 	 * Abort in:
414 	 * -error case
415 	 * -read memory map: prefetching must be stopped if we read the last
416 	 *  byte of device (device size - fifo size). like device size is not
417 	 *  knows, the prefetching is always stop.
418 	 */
419 	if (err || err_poll_status || qspi->fmode == CCR_FMODE_MM)
420 		goto abort;
421 
422 	/* wait end of tx in indirect mode */
423 	err = stm32_qspi_wait_cmd(qspi, op);
424 	if (err)
425 		goto abort;
426 
427 	return 0;
428 
429 abort:
430 	cr = readl_relaxed(qspi->io_base + QSPI_CR) | CR_ABORT;
431 	writel_relaxed(cr, qspi->io_base + QSPI_CR);
432 
433 	/* wait clear of abort bit by hw */
434 	timeout = readl_relaxed_poll_timeout_atomic(qspi->io_base + QSPI_CR,
435 						    cr, !(cr & CR_ABORT), 1,
436 						    STM32_ABT_TIMEOUT_US);
437 
438 	writel_relaxed(FCR_CTCF | FCR_CSMF, qspi->io_base + QSPI_FCR);
439 
440 	if (err || err_poll_status || timeout)
441 		dev_err(qspi->dev, "%s err:%d err_poll_status:%d abort timeout:%d\n",
442 			__func__, err, err_poll_status, timeout);
443 
444 	return err;
445 }
446 
447 static int stm32_qspi_poll_status(struct spi_mem *mem, const struct spi_mem_op *op,
448 				  u16 mask, u16 match,
449 				  unsigned long initial_delay_us,
450 				  unsigned long polling_rate_us,
451 				  unsigned long timeout_ms)
452 {
453 	struct stm32_qspi *qspi = spi_controller_get_devdata(mem->spi->master);
454 	int ret;
455 
456 	if (!spi_mem_supports_op(mem, op))
457 		return -EOPNOTSUPP;
458 
459 	ret = pm_runtime_resume_and_get(qspi->dev);
460 	if (ret < 0)
461 		return ret;
462 
463 	mutex_lock(&qspi->lock);
464 
465 	writel_relaxed(mask, qspi->io_base + QSPI_PSMKR);
466 	writel_relaxed(match, qspi->io_base + QSPI_PSMAR);
467 	qspi->fmode = CCR_FMODE_APM;
468 	qspi->status_timeout = timeout_ms;
469 
470 	ret = stm32_qspi_send(mem, op);
471 	mutex_unlock(&qspi->lock);
472 
473 	pm_runtime_mark_last_busy(qspi->dev);
474 	pm_runtime_put_autosuspend(qspi->dev);
475 
476 	return ret;
477 }
478 
479 static int stm32_qspi_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
480 {
481 	struct stm32_qspi *qspi = spi_controller_get_devdata(mem->spi->master);
482 	int ret;
483 
484 	ret = pm_runtime_resume_and_get(qspi->dev);
485 	if (ret < 0)
486 		return ret;
487 
488 	mutex_lock(&qspi->lock);
489 	if (op->data.dir == SPI_MEM_DATA_IN && op->data.nbytes)
490 		qspi->fmode = CCR_FMODE_INDR;
491 	else
492 		qspi->fmode = CCR_FMODE_INDW;
493 
494 	ret = stm32_qspi_send(mem, op);
495 	mutex_unlock(&qspi->lock);
496 
497 	pm_runtime_mark_last_busy(qspi->dev);
498 	pm_runtime_put_autosuspend(qspi->dev);
499 
500 	return ret;
501 }
502 
503 static int stm32_qspi_dirmap_create(struct spi_mem_dirmap_desc *desc)
504 {
505 	struct stm32_qspi *qspi = spi_controller_get_devdata(desc->mem->spi->master);
506 
507 	if (desc->info.op_tmpl.data.dir == SPI_MEM_DATA_OUT)
508 		return -EOPNOTSUPP;
509 
510 	/* should never happen, as mm_base == null is an error probe exit condition */
511 	if (!qspi->mm_base && desc->info.op_tmpl.data.dir == SPI_MEM_DATA_IN)
512 		return -EOPNOTSUPP;
513 
514 	if (!qspi->mm_size)
515 		return -EOPNOTSUPP;
516 
517 	return 0;
518 }
519 
520 static ssize_t stm32_qspi_dirmap_read(struct spi_mem_dirmap_desc *desc,
521 				      u64 offs, size_t len, void *buf)
522 {
523 	struct stm32_qspi *qspi = spi_controller_get_devdata(desc->mem->spi->master);
524 	struct spi_mem_op op;
525 	u32 addr_max;
526 	int ret;
527 
528 	ret = pm_runtime_resume_and_get(qspi->dev);
529 	if (ret < 0)
530 		return ret;
531 
532 	mutex_lock(&qspi->lock);
533 	/* make a local copy of desc op_tmpl and complete dirmap rdesc
534 	 * spi_mem_op template with offs, len and *buf in  order to get
535 	 * all needed transfer information into struct spi_mem_op
536 	 */
537 	memcpy(&op, &desc->info.op_tmpl, sizeof(struct spi_mem_op));
538 	dev_dbg(qspi->dev, "%s len = 0x%zx offs = 0x%llx buf = 0x%p\n", __func__, len, offs, buf);
539 
540 	op.data.nbytes = len;
541 	op.addr.val = desc->info.offset + offs;
542 	op.data.buf.in = buf;
543 
544 	addr_max = op.addr.val + op.data.nbytes + 1;
545 	if (addr_max < qspi->mm_size && op.addr.buswidth)
546 		qspi->fmode = CCR_FMODE_MM;
547 	else
548 		qspi->fmode = CCR_FMODE_INDR;
549 
550 	ret = stm32_qspi_send(desc->mem, &op);
551 	mutex_unlock(&qspi->lock);
552 
553 	pm_runtime_mark_last_busy(qspi->dev);
554 	pm_runtime_put_autosuspend(qspi->dev);
555 
556 	return ret ?: len;
557 }
558 
559 static int stm32_qspi_setup(struct spi_device *spi)
560 {
561 	struct spi_controller *ctrl = spi->master;
562 	struct stm32_qspi *qspi = spi_controller_get_devdata(ctrl);
563 	struct stm32_qspi_flash *flash;
564 	u32 presc;
565 	int ret;
566 
567 	if (ctrl->busy)
568 		return -EBUSY;
569 
570 	if (!spi->max_speed_hz)
571 		return -EINVAL;
572 
573 	ret = pm_runtime_resume_and_get(qspi->dev);
574 	if (ret < 0)
575 		return ret;
576 
577 	presc = DIV_ROUND_UP(qspi->clk_rate, spi->max_speed_hz) - 1;
578 
579 	flash = &qspi->flash[spi->chip_select];
580 	flash->cs = spi->chip_select;
581 	flash->presc = presc;
582 
583 	mutex_lock(&qspi->lock);
584 	qspi->cr_reg = CR_APMS | 3 << CR_FTHRES_SHIFT | CR_SSHIFT | CR_EN;
585 	writel_relaxed(qspi->cr_reg, qspi->io_base + QSPI_CR);
586 
587 	/* set dcr fsize to max address */
588 	qspi->dcr_reg = DCR_FSIZE_MASK;
589 	writel_relaxed(qspi->dcr_reg, qspi->io_base + QSPI_DCR);
590 	mutex_unlock(&qspi->lock);
591 
592 	pm_runtime_mark_last_busy(qspi->dev);
593 	pm_runtime_put_autosuspend(qspi->dev);
594 
595 	return 0;
596 }
597 
598 static int stm32_qspi_dma_setup(struct stm32_qspi *qspi)
599 {
600 	struct dma_slave_config dma_cfg;
601 	struct device *dev = qspi->dev;
602 	int ret = 0;
603 
604 	memset(&dma_cfg, 0, sizeof(dma_cfg));
605 
606 	dma_cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
607 	dma_cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
608 	dma_cfg.src_addr = qspi->phys_base + QSPI_DR;
609 	dma_cfg.dst_addr = qspi->phys_base + QSPI_DR;
610 	dma_cfg.src_maxburst = 4;
611 	dma_cfg.dst_maxburst = 4;
612 
613 	qspi->dma_chrx = dma_request_chan(dev, "rx");
614 	if (IS_ERR(qspi->dma_chrx)) {
615 		ret = PTR_ERR(qspi->dma_chrx);
616 		qspi->dma_chrx = NULL;
617 		if (ret == -EPROBE_DEFER)
618 			goto out;
619 	} else {
620 		if (dmaengine_slave_config(qspi->dma_chrx, &dma_cfg)) {
621 			dev_err(dev, "dma rx config failed\n");
622 			dma_release_channel(qspi->dma_chrx);
623 			qspi->dma_chrx = NULL;
624 		}
625 	}
626 
627 	qspi->dma_chtx = dma_request_chan(dev, "tx");
628 	if (IS_ERR(qspi->dma_chtx)) {
629 		ret = PTR_ERR(qspi->dma_chtx);
630 		qspi->dma_chtx = NULL;
631 	} else {
632 		if (dmaengine_slave_config(qspi->dma_chtx, &dma_cfg)) {
633 			dev_err(dev, "dma tx config failed\n");
634 			dma_release_channel(qspi->dma_chtx);
635 			qspi->dma_chtx = NULL;
636 		}
637 	}
638 
639 out:
640 	init_completion(&qspi->dma_completion);
641 
642 	if (ret != -EPROBE_DEFER)
643 		ret = 0;
644 
645 	return ret;
646 }
647 
648 static void stm32_qspi_dma_free(struct stm32_qspi *qspi)
649 {
650 	if (qspi->dma_chtx)
651 		dma_release_channel(qspi->dma_chtx);
652 	if (qspi->dma_chrx)
653 		dma_release_channel(qspi->dma_chrx);
654 }
655 
656 /*
657  * no special host constraint, so use default spi_mem_default_supports_op
658  * to check supported mode.
659  */
660 static const struct spi_controller_mem_ops stm32_qspi_mem_ops = {
661 	.exec_op	= stm32_qspi_exec_op,
662 	.dirmap_create	= stm32_qspi_dirmap_create,
663 	.dirmap_read	= stm32_qspi_dirmap_read,
664 	.poll_status	= stm32_qspi_poll_status,
665 };
666 
667 static int stm32_qspi_probe(struct platform_device *pdev)
668 {
669 	struct device *dev = &pdev->dev;
670 	struct spi_controller *ctrl;
671 	struct reset_control *rstc;
672 	struct stm32_qspi *qspi;
673 	struct resource *res;
674 	int ret, irq;
675 
676 	ctrl = devm_spi_alloc_master(dev, sizeof(*qspi));
677 	if (!ctrl)
678 		return -ENOMEM;
679 
680 	qspi = spi_controller_get_devdata(ctrl);
681 	qspi->ctrl = ctrl;
682 
683 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "qspi");
684 	qspi->io_base = devm_ioremap_resource(dev, res);
685 	if (IS_ERR(qspi->io_base))
686 		return PTR_ERR(qspi->io_base);
687 
688 	qspi->phys_base = res->start;
689 
690 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "qspi_mm");
691 	qspi->mm_base = devm_ioremap_resource(dev, res);
692 	if (IS_ERR(qspi->mm_base))
693 		return PTR_ERR(qspi->mm_base);
694 
695 	qspi->mm_size = resource_size(res);
696 	if (qspi->mm_size > STM32_QSPI_MAX_MMAP_SZ)
697 		return -EINVAL;
698 
699 	irq = platform_get_irq(pdev, 0);
700 	if (irq < 0)
701 		return irq;
702 
703 	ret = devm_request_irq(dev, irq, stm32_qspi_irq, 0,
704 			       dev_name(dev), qspi);
705 	if (ret) {
706 		dev_err(dev, "failed to request irq\n");
707 		return ret;
708 	}
709 
710 	init_completion(&qspi->data_completion);
711 	init_completion(&qspi->match_completion);
712 
713 	qspi->clk = devm_clk_get(dev, NULL);
714 	if (IS_ERR(qspi->clk))
715 		return PTR_ERR(qspi->clk);
716 
717 	qspi->clk_rate = clk_get_rate(qspi->clk);
718 	if (!qspi->clk_rate)
719 		return -EINVAL;
720 
721 	ret = clk_prepare_enable(qspi->clk);
722 	if (ret) {
723 		dev_err(dev, "can not enable the clock\n");
724 		return ret;
725 	}
726 
727 	rstc = devm_reset_control_get_exclusive(dev, NULL);
728 	if (IS_ERR(rstc)) {
729 		ret = PTR_ERR(rstc);
730 		if (ret == -EPROBE_DEFER)
731 			goto err_clk_disable;
732 	} else {
733 		reset_control_assert(rstc);
734 		udelay(2);
735 		reset_control_deassert(rstc);
736 	}
737 
738 	qspi->dev = dev;
739 	platform_set_drvdata(pdev, qspi);
740 	ret = stm32_qspi_dma_setup(qspi);
741 	if (ret)
742 		goto err_dma_free;
743 
744 	mutex_init(&qspi->lock);
745 
746 	ctrl->mode_bits = SPI_RX_DUAL | SPI_RX_QUAD
747 		| SPI_TX_DUAL | SPI_TX_QUAD;
748 	ctrl->setup = stm32_qspi_setup;
749 	ctrl->bus_num = -1;
750 	ctrl->mem_ops = &stm32_qspi_mem_ops;
751 	ctrl->num_chipselect = STM32_QSPI_MAX_NORCHIP;
752 	ctrl->dev.of_node = dev->of_node;
753 
754 	pm_runtime_set_autosuspend_delay(dev, STM32_AUTOSUSPEND_DELAY);
755 	pm_runtime_use_autosuspend(dev);
756 	pm_runtime_set_active(dev);
757 	pm_runtime_enable(dev);
758 	pm_runtime_get_noresume(dev);
759 
760 	ret = spi_register_master(ctrl);
761 	if (ret)
762 		goto err_pm_runtime_free;
763 
764 	pm_runtime_mark_last_busy(dev);
765 	pm_runtime_put_autosuspend(dev);
766 
767 	return 0;
768 
769 err_pm_runtime_free:
770 	pm_runtime_get_sync(qspi->dev);
771 	/* disable qspi */
772 	writel_relaxed(0, qspi->io_base + QSPI_CR);
773 	mutex_destroy(&qspi->lock);
774 	pm_runtime_put_noidle(qspi->dev);
775 	pm_runtime_disable(qspi->dev);
776 	pm_runtime_set_suspended(qspi->dev);
777 	pm_runtime_dont_use_autosuspend(qspi->dev);
778 err_dma_free:
779 	stm32_qspi_dma_free(qspi);
780 err_clk_disable:
781 	clk_disable_unprepare(qspi->clk);
782 
783 	return ret;
784 }
785 
786 static int stm32_qspi_remove(struct platform_device *pdev)
787 {
788 	struct stm32_qspi *qspi = platform_get_drvdata(pdev);
789 
790 	pm_runtime_get_sync(qspi->dev);
791 	spi_unregister_master(qspi->ctrl);
792 	/* disable qspi */
793 	writel_relaxed(0, qspi->io_base + QSPI_CR);
794 	stm32_qspi_dma_free(qspi);
795 	mutex_destroy(&qspi->lock);
796 	pm_runtime_put_noidle(qspi->dev);
797 	pm_runtime_disable(qspi->dev);
798 	pm_runtime_set_suspended(qspi->dev);
799 	pm_runtime_dont_use_autosuspend(qspi->dev);
800 	clk_disable_unprepare(qspi->clk);
801 
802 	return 0;
803 }
804 
805 static int __maybe_unused stm32_qspi_runtime_suspend(struct device *dev)
806 {
807 	struct stm32_qspi *qspi = dev_get_drvdata(dev);
808 
809 	clk_disable_unprepare(qspi->clk);
810 
811 	return 0;
812 }
813 
814 static int __maybe_unused stm32_qspi_runtime_resume(struct device *dev)
815 {
816 	struct stm32_qspi *qspi = dev_get_drvdata(dev);
817 
818 	return clk_prepare_enable(qspi->clk);
819 }
820 
821 static int __maybe_unused stm32_qspi_suspend(struct device *dev)
822 {
823 	pinctrl_pm_select_sleep_state(dev);
824 
825 	return pm_runtime_force_suspend(dev);
826 }
827 
828 static int __maybe_unused stm32_qspi_resume(struct device *dev)
829 {
830 	struct stm32_qspi *qspi = dev_get_drvdata(dev);
831 	int ret;
832 
833 	ret = pm_runtime_force_resume(dev);
834 	if (ret < 0)
835 		return ret;
836 
837 	pinctrl_pm_select_default_state(dev);
838 
839 	ret = pm_runtime_resume_and_get(dev);
840 	if (ret < 0)
841 		return ret;
842 
843 	writel_relaxed(qspi->cr_reg, qspi->io_base + QSPI_CR);
844 	writel_relaxed(qspi->dcr_reg, qspi->io_base + QSPI_DCR);
845 
846 	pm_runtime_mark_last_busy(dev);
847 	pm_runtime_put_autosuspend(dev);
848 
849 	return 0;
850 }
851 
852 static const struct dev_pm_ops stm32_qspi_pm_ops = {
853 	SET_RUNTIME_PM_OPS(stm32_qspi_runtime_suspend,
854 			   stm32_qspi_runtime_resume, NULL)
855 	SET_SYSTEM_SLEEP_PM_OPS(stm32_qspi_suspend, stm32_qspi_resume)
856 };
857 
858 static const struct of_device_id stm32_qspi_match[] = {
859 	{.compatible = "st,stm32f469-qspi"},
860 	{}
861 };
862 MODULE_DEVICE_TABLE(of, stm32_qspi_match);
863 
864 static struct platform_driver stm32_qspi_driver = {
865 	.probe	= stm32_qspi_probe,
866 	.remove	= stm32_qspi_remove,
867 	.driver	= {
868 		.name = "stm32-qspi",
869 		.of_match_table = stm32_qspi_match,
870 		.pm = &stm32_qspi_pm_ops,
871 	},
872 };
873 module_platform_driver(stm32_qspi_driver);
874 
875 MODULE_AUTHOR("Ludovic Barre <ludovic.barre@st.com>");
876 MODULE_DESCRIPTION("STMicroelectronics STM32 quad spi driver");
877 MODULE_LICENSE("GPL v2");
878