xref: /openbmc/linux/drivers/spi/spi-stm32-qspi.c (revision 63705da3)
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 (!op->data.nbytes)
309 		goto wait_nobusy;
310 
311 	if (readl_relaxed(qspi->io_base + QSPI_SR) & SR_TCF)
312 		goto out;
313 
314 	reinit_completion(&qspi->data_completion);
315 	cr = readl_relaxed(qspi->io_base + QSPI_CR);
316 	writel_relaxed(cr | CR_TCIE | CR_TEIE, qspi->io_base + QSPI_CR);
317 
318 	if (!wait_for_completion_timeout(&qspi->data_completion,
319 				msecs_to_jiffies(STM32_COMP_TIMEOUT_MS))) {
320 		err = -ETIMEDOUT;
321 	} else {
322 		sr = readl_relaxed(qspi->io_base + QSPI_SR);
323 		if (sr & SR_TEF)
324 			err = -EIO;
325 	}
326 
327 out:
328 	/* clear flags */
329 	writel_relaxed(FCR_CTCF | FCR_CTEF, qspi->io_base + QSPI_FCR);
330 wait_nobusy:
331 	if (!err)
332 		err = stm32_qspi_wait_nobusy(qspi);
333 
334 	return err;
335 }
336 
337 static int stm32_qspi_wait_poll_status(struct stm32_qspi *qspi,
338 				       const struct spi_mem_op *op)
339 {
340 	u32 cr;
341 
342 	reinit_completion(&qspi->match_completion);
343 	cr = readl_relaxed(qspi->io_base + QSPI_CR);
344 	writel_relaxed(cr | CR_SMIE, qspi->io_base + QSPI_CR);
345 
346 	if (!wait_for_completion_timeout(&qspi->match_completion,
347 				msecs_to_jiffies(qspi->status_timeout)))
348 		return -ETIMEDOUT;
349 
350 	writel_relaxed(FCR_CSMF, qspi->io_base + QSPI_FCR);
351 
352 	return 0;
353 }
354 
355 static int stm32_qspi_get_mode(struct stm32_qspi *qspi, u8 buswidth)
356 {
357 	if (buswidth == 4)
358 		return CCR_BUSWIDTH_4;
359 
360 	return buswidth;
361 }
362 
363 static int stm32_qspi_send(struct spi_mem *mem, const struct spi_mem_op *op)
364 {
365 	struct stm32_qspi *qspi = spi_controller_get_devdata(mem->spi->master);
366 	struct stm32_qspi_flash *flash = &qspi->flash[mem->spi->chip_select];
367 	u32 ccr, cr;
368 	int timeout, err = 0, err_poll_status = 0;
369 
370 	dev_dbg(qspi->dev, "cmd:%#x mode:%d.%d.%d.%d addr:%#llx len:%#x\n",
371 		op->cmd.opcode, op->cmd.buswidth, op->addr.buswidth,
372 		op->dummy.buswidth, op->data.buswidth,
373 		op->addr.val, op->data.nbytes);
374 
375 	err = stm32_qspi_wait_nobusy(qspi);
376 	if (err)
377 		goto abort;
378 
379 	cr = readl_relaxed(qspi->io_base + QSPI_CR);
380 	cr &= ~CR_PRESC_MASK & ~CR_FSEL;
381 	cr |= FIELD_PREP(CR_PRESC_MASK, flash->presc);
382 	cr |= FIELD_PREP(CR_FSEL, flash->cs);
383 	writel_relaxed(cr, qspi->io_base + QSPI_CR);
384 
385 	if (op->data.nbytes)
386 		writel_relaxed(op->data.nbytes - 1,
387 			       qspi->io_base + QSPI_DLR);
388 
389 	ccr = qspi->fmode;
390 	ccr |= FIELD_PREP(CCR_INST_MASK, op->cmd.opcode);
391 	ccr |= FIELD_PREP(CCR_IMODE_MASK,
392 			  stm32_qspi_get_mode(qspi, op->cmd.buswidth));
393 
394 	if (op->addr.nbytes) {
395 		ccr |= FIELD_PREP(CCR_ADMODE_MASK,
396 				  stm32_qspi_get_mode(qspi, op->addr.buswidth));
397 		ccr |= FIELD_PREP(CCR_ADSIZE_MASK, op->addr.nbytes - 1);
398 	}
399 
400 	if (op->dummy.nbytes)
401 		ccr |= FIELD_PREP(CCR_DCYC_MASK,
402 				  op->dummy.nbytes * 8 / op->dummy.buswidth);
403 
404 	if (op->data.nbytes) {
405 		ccr |= FIELD_PREP(CCR_DMODE_MASK,
406 				  stm32_qspi_get_mode(qspi, op->data.buswidth));
407 	}
408 
409 	writel_relaxed(ccr, qspi->io_base + QSPI_CCR);
410 
411 	if (op->addr.nbytes && qspi->fmode != CCR_FMODE_MM)
412 		writel_relaxed(op->addr.val, qspi->io_base + QSPI_AR);
413 
414 	if (qspi->fmode == CCR_FMODE_APM)
415 		err_poll_status = stm32_qspi_wait_poll_status(qspi, op);
416 
417 	err = stm32_qspi_tx(qspi, op);
418 
419 	/*
420 	 * Abort in:
421 	 * -error case
422 	 * -read memory map: prefetching must be stopped if we read the last
423 	 *  byte of device (device size - fifo size). like device size is not
424 	 *  knows, the prefetching is always stop.
425 	 */
426 	if (err || err_poll_status || qspi->fmode == CCR_FMODE_MM)
427 		goto abort;
428 
429 	/* wait end of tx in indirect mode */
430 	err = stm32_qspi_wait_cmd(qspi, op);
431 	if (err)
432 		goto abort;
433 
434 	return 0;
435 
436 abort:
437 	cr = readl_relaxed(qspi->io_base + QSPI_CR) | CR_ABORT;
438 	writel_relaxed(cr, qspi->io_base + QSPI_CR);
439 
440 	/* wait clear of abort bit by hw */
441 	timeout = readl_relaxed_poll_timeout_atomic(qspi->io_base + QSPI_CR,
442 						    cr, !(cr & CR_ABORT), 1,
443 						    STM32_ABT_TIMEOUT_US);
444 
445 	writel_relaxed(FCR_CTCF | FCR_CSMF, qspi->io_base + QSPI_FCR);
446 
447 	if (err || err_poll_status || timeout)
448 		dev_err(qspi->dev, "%s err:%d err_poll_status:%d abort timeout:%d\n",
449 			__func__, err, err_poll_status, timeout);
450 
451 	return err;
452 }
453 
454 static int stm32_qspi_poll_status(struct spi_mem *mem, const struct spi_mem_op *op,
455 				  u16 mask, u16 match,
456 				  unsigned long initial_delay_us,
457 				  unsigned long polling_rate_us,
458 				  unsigned long timeout_ms)
459 {
460 	struct stm32_qspi *qspi = spi_controller_get_devdata(mem->spi->master);
461 	int ret;
462 
463 	if (!spi_mem_supports_op(mem, op))
464 		return -EOPNOTSUPP;
465 
466 	ret = pm_runtime_get_sync(qspi->dev);
467 	if (ret < 0) {
468 		pm_runtime_put_noidle(qspi->dev);
469 		return ret;
470 	}
471 
472 	mutex_lock(&qspi->lock);
473 
474 	writel_relaxed(mask, qspi->io_base + QSPI_PSMKR);
475 	writel_relaxed(match, qspi->io_base + QSPI_PSMAR);
476 	qspi->fmode = CCR_FMODE_APM;
477 	qspi->status_timeout = timeout_ms;
478 
479 	ret = stm32_qspi_send(mem, op);
480 	mutex_unlock(&qspi->lock);
481 
482 	pm_runtime_mark_last_busy(qspi->dev);
483 	pm_runtime_put_autosuspend(qspi->dev);
484 
485 	return ret;
486 }
487 
488 static int stm32_qspi_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
489 {
490 	struct stm32_qspi *qspi = spi_controller_get_devdata(mem->spi->master);
491 	int ret;
492 
493 	ret = pm_runtime_get_sync(qspi->dev);
494 	if (ret < 0) {
495 		pm_runtime_put_noidle(qspi->dev);
496 		return ret;
497 	}
498 
499 	mutex_lock(&qspi->lock);
500 	if (op->data.dir == SPI_MEM_DATA_IN && op->data.nbytes)
501 		qspi->fmode = CCR_FMODE_INDR;
502 	else
503 		qspi->fmode = CCR_FMODE_INDW;
504 
505 	ret = stm32_qspi_send(mem, op);
506 	mutex_unlock(&qspi->lock);
507 
508 	pm_runtime_mark_last_busy(qspi->dev);
509 	pm_runtime_put_autosuspend(qspi->dev);
510 
511 	return ret;
512 }
513 
514 static int stm32_qspi_dirmap_create(struct spi_mem_dirmap_desc *desc)
515 {
516 	struct stm32_qspi *qspi = spi_controller_get_devdata(desc->mem->spi->master);
517 
518 	if (desc->info.op_tmpl.data.dir == SPI_MEM_DATA_OUT)
519 		return -EOPNOTSUPP;
520 
521 	/* should never happen, as mm_base == null is an error probe exit condition */
522 	if (!qspi->mm_base && desc->info.op_tmpl.data.dir == SPI_MEM_DATA_IN)
523 		return -EOPNOTSUPP;
524 
525 	if (!qspi->mm_size)
526 		return -EOPNOTSUPP;
527 
528 	return 0;
529 }
530 
531 static ssize_t stm32_qspi_dirmap_read(struct spi_mem_dirmap_desc *desc,
532 				      u64 offs, size_t len, void *buf)
533 {
534 	struct stm32_qspi *qspi = spi_controller_get_devdata(desc->mem->spi->master);
535 	struct spi_mem_op op;
536 	u32 addr_max;
537 	int ret;
538 
539 	ret = pm_runtime_get_sync(qspi->dev);
540 	if (ret < 0) {
541 		pm_runtime_put_noidle(qspi->dev);
542 		return ret;
543 	}
544 
545 	mutex_lock(&qspi->lock);
546 	/* make a local copy of desc op_tmpl and complete dirmap rdesc
547 	 * spi_mem_op template with offs, len and *buf in  order to get
548 	 * all needed transfer information into struct spi_mem_op
549 	 */
550 	memcpy(&op, &desc->info.op_tmpl, sizeof(struct spi_mem_op));
551 	dev_dbg(qspi->dev, "%s len = 0x%zx offs = 0x%llx buf = 0x%p\n", __func__, len, offs, buf);
552 
553 	op.data.nbytes = len;
554 	op.addr.val = desc->info.offset + offs;
555 	op.data.buf.in = buf;
556 
557 	addr_max = op.addr.val + op.data.nbytes + 1;
558 	if (addr_max < qspi->mm_size && op.addr.buswidth)
559 		qspi->fmode = CCR_FMODE_MM;
560 	else
561 		qspi->fmode = CCR_FMODE_INDR;
562 
563 	ret = stm32_qspi_send(desc->mem, &op);
564 	mutex_unlock(&qspi->lock);
565 
566 	pm_runtime_mark_last_busy(qspi->dev);
567 	pm_runtime_put_autosuspend(qspi->dev);
568 
569 	return ret ?: len;
570 }
571 
572 static int stm32_qspi_setup(struct spi_device *spi)
573 {
574 	struct spi_controller *ctrl = spi->master;
575 	struct stm32_qspi *qspi = spi_controller_get_devdata(ctrl);
576 	struct stm32_qspi_flash *flash;
577 	u32 presc;
578 	int ret;
579 
580 	if (ctrl->busy)
581 		return -EBUSY;
582 
583 	if (!spi->max_speed_hz)
584 		return -EINVAL;
585 
586 	ret = pm_runtime_get_sync(qspi->dev);
587 	if (ret < 0) {
588 		pm_runtime_put_noidle(qspi->dev);
589 		return ret;
590 	}
591 
592 	presc = DIV_ROUND_UP(qspi->clk_rate, spi->max_speed_hz) - 1;
593 
594 	flash = &qspi->flash[spi->chip_select];
595 	flash->cs = spi->chip_select;
596 	flash->presc = presc;
597 
598 	mutex_lock(&qspi->lock);
599 	qspi->cr_reg = CR_APMS | 3 << CR_FTHRES_SHIFT | CR_SSHIFT | CR_EN;
600 	writel_relaxed(qspi->cr_reg, qspi->io_base + QSPI_CR);
601 
602 	/* set dcr fsize to max address */
603 	qspi->dcr_reg = DCR_FSIZE_MASK;
604 	writel_relaxed(qspi->dcr_reg, qspi->io_base + QSPI_DCR);
605 	mutex_unlock(&qspi->lock);
606 
607 	pm_runtime_mark_last_busy(qspi->dev);
608 	pm_runtime_put_autosuspend(qspi->dev);
609 
610 	return 0;
611 }
612 
613 static int stm32_qspi_dma_setup(struct stm32_qspi *qspi)
614 {
615 	struct dma_slave_config dma_cfg;
616 	struct device *dev = qspi->dev;
617 	int ret = 0;
618 
619 	memset(&dma_cfg, 0, sizeof(dma_cfg));
620 
621 	dma_cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
622 	dma_cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
623 	dma_cfg.src_addr = qspi->phys_base + QSPI_DR;
624 	dma_cfg.dst_addr = qspi->phys_base + QSPI_DR;
625 	dma_cfg.src_maxburst = 4;
626 	dma_cfg.dst_maxburst = 4;
627 
628 	qspi->dma_chrx = dma_request_chan(dev, "rx");
629 	if (IS_ERR(qspi->dma_chrx)) {
630 		ret = PTR_ERR(qspi->dma_chrx);
631 		qspi->dma_chrx = NULL;
632 		if (ret == -EPROBE_DEFER)
633 			goto out;
634 	} else {
635 		if (dmaengine_slave_config(qspi->dma_chrx, &dma_cfg)) {
636 			dev_err(dev, "dma rx config failed\n");
637 			dma_release_channel(qspi->dma_chrx);
638 			qspi->dma_chrx = NULL;
639 		}
640 	}
641 
642 	qspi->dma_chtx = dma_request_chan(dev, "tx");
643 	if (IS_ERR(qspi->dma_chtx)) {
644 		ret = PTR_ERR(qspi->dma_chtx);
645 		qspi->dma_chtx = NULL;
646 	} else {
647 		if (dmaengine_slave_config(qspi->dma_chtx, &dma_cfg)) {
648 			dev_err(dev, "dma tx config failed\n");
649 			dma_release_channel(qspi->dma_chtx);
650 			qspi->dma_chtx = NULL;
651 		}
652 	}
653 
654 out:
655 	init_completion(&qspi->dma_completion);
656 
657 	if (ret != -EPROBE_DEFER)
658 		ret = 0;
659 
660 	return ret;
661 }
662 
663 static void stm32_qspi_dma_free(struct stm32_qspi *qspi)
664 {
665 	if (qspi->dma_chtx)
666 		dma_release_channel(qspi->dma_chtx);
667 	if (qspi->dma_chrx)
668 		dma_release_channel(qspi->dma_chrx);
669 }
670 
671 /*
672  * no special host constraint, so use default spi_mem_default_supports_op
673  * to check supported mode.
674  */
675 static const struct spi_controller_mem_ops stm32_qspi_mem_ops = {
676 	.exec_op	= stm32_qspi_exec_op,
677 	.dirmap_create	= stm32_qspi_dirmap_create,
678 	.dirmap_read	= stm32_qspi_dirmap_read,
679 	.poll_status	= stm32_qspi_poll_status,
680 };
681 
682 static int stm32_qspi_probe(struct platform_device *pdev)
683 {
684 	struct device *dev = &pdev->dev;
685 	struct spi_controller *ctrl;
686 	struct reset_control *rstc;
687 	struct stm32_qspi *qspi;
688 	struct resource *res;
689 	int ret, irq;
690 
691 	ctrl = spi_alloc_master(dev, sizeof(*qspi));
692 	if (!ctrl)
693 		return -ENOMEM;
694 
695 	qspi = spi_controller_get_devdata(ctrl);
696 	qspi->ctrl = ctrl;
697 
698 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "qspi");
699 	qspi->io_base = devm_ioremap_resource(dev, res);
700 	if (IS_ERR(qspi->io_base)) {
701 		ret = PTR_ERR(qspi->io_base);
702 		goto err_master_put;
703 	}
704 
705 	qspi->phys_base = res->start;
706 
707 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "qspi_mm");
708 	qspi->mm_base = devm_ioremap_resource(dev, res);
709 	if (IS_ERR(qspi->mm_base)) {
710 		ret = PTR_ERR(qspi->mm_base);
711 		goto err_master_put;
712 	}
713 
714 	qspi->mm_size = resource_size(res);
715 	if (qspi->mm_size > STM32_QSPI_MAX_MMAP_SZ) {
716 		ret = -EINVAL;
717 		goto err_master_put;
718 	}
719 
720 	irq = platform_get_irq(pdev, 0);
721 	if (irq < 0) {
722 		ret = irq;
723 		goto err_master_put;
724 	}
725 
726 	ret = devm_request_irq(dev, irq, stm32_qspi_irq, 0,
727 			       dev_name(dev), qspi);
728 	if (ret) {
729 		dev_err(dev, "failed to request irq\n");
730 		goto err_master_put;
731 	}
732 
733 	init_completion(&qspi->data_completion);
734 	init_completion(&qspi->match_completion);
735 
736 	qspi->clk = devm_clk_get(dev, NULL);
737 	if (IS_ERR(qspi->clk)) {
738 		ret = PTR_ERR(qspi->clk);
739 		goto err_master_put;
740 	}
741 
742 	qspi->clk_rate = clk_get_rate(qspi->clk);
743 	if (!qspi->clk_rate) {
744 		ret = -EINVAL;
745 		goto err_master_put;
746 	}
747 
748 	ret = clk_prepare_enable(qspi->clk);
749 	if (ret) {
750 		dev_err(dev, "can not enable the clock\n");
751 		goto err_master_put;
752 	}
753 
754 	rstc = devm_reset_control_get_exclusive(dev, NULL);
755 	if (IS_ERR(rstc)) {
756 		ret = PTR_ERR(rstc);
757 		if (ret == -EPROBE_DEFER)
758 			goto err_clk_disable;
759 	} else {
760 		reset_control_assert(rstc);
761 		udelay(2);
762 		reset_control_deassert(rstc);
763 	}
764 
765 	qspi->dev = dev;
766 	platform_set_drvdata(pdev, qspi);
767 	ret = stm32_qspi_dma_setup(qspi);
768 	if (ret)
769 		goto err_dma_free;
770 
771 	mutex_init(&qspi->lock);
772 
773 	ctrl->mode_bits = SPI_RX_DUAL | SPI_RX_QUAD
774 		| SPI_TX_DUAL | SPI_TX_QUAD;
775 	ctrl->setup = stm32_qspi_setup;
776 	ctrl->bus_num = -1;
777 	ctrl->mem_ops = &stm32_qspi_mem_ops;
778 	ctrl->num_chipselect = STM32_QSPI_MAX_NORCHIP;
779 	ctrl->dev.of_node = dev->of_node;
780 
781 	pm_runtime_set_autosuspend_delay(dev, STM32_AUTOSUSPEND_DELAY);
782 	pm_runtime_use_autosuspend(dev);
783 	pm_runtime_set_active(dev);
784 	pm_runtime_enable(dev);
785 	pm_runtime_get_noresume(dev);
786 
787 	ret = devm_spi_register_master(dev, ctrl);
788 	if (ret)
789 		goto err_pm_runtime_free;
790 
791 	pm_runtime_mark_last_busy(dev);
792 	pm_runtime_put_autosuspend(dev);
793 
794 	return 0;
795 
796 err_pm_runtime_free:
797 	pm_runtime_get_sync(qspi->dev);
798 	/* disable qspi */
799 	writel_relaxed(0, qspi->io_base + QSPI_CR);
800 	mutex_destroy(&qspi->lock);
801 	pm_runtime_put_noidle(qspi->dev);
802 	pm_runtime_disable(qspi->dev);
803 	pm_runtime_set_suspended(qspi->dev);
804 	pm_runtime_dont_use_autosuspend(qspi->dev);
805 err_dma_free:
806 	stm32_qspi_dma_free(qspi);
807 err_clk_disable:
808 	clk_disable_unprepare(qspi->clk);
809 err_master_put:
810 	spi_master_put(qspi->ctrl);
811 
812 	return ret;
813 }
814 
815 static int stm32_qspi_remove(struct platform_device *pdev)
816 {
817 	struct stm32_qspi *qspi = platform_get_drvdata(pdev);
818 
819 	pm_runtime_get_sync(qspi->dev);
820 	/* disable qspi */
821 	writel_relaxed(0, qspi->io_base + QSPI_CR);
822 	stm32_qspi_dma_free(qspi);
823 	mutex_destroy(&qspi->lock);
824 	pm_runtime_put_noidle(qspi->dev);
825 	pm_runtime_disable(qspi->dev);
826 	pm_runtime_set_suspended(qspi->dev);
827 	pm_runtime_dont_use_autosuspend(qspi->dev);
828 	clk_disable_unprepare(qspi->clk);
829 
830 	return 0;
831 }
832 
833 static int __maybe_unused stm32_qspi_runtime_suspend(struct device *dev)
834 {
835 	struct stm32_qspi *qspi = dev_get_drvdata(dev);
836 
837 	clk_disable_unprepare(qspi->clk);
838 
839 	return 0;
840 }
841 
842 static int __maybe_unused stm32_qspi_runtime_resume(struct device *dev)
843 {
844 	struct stm32_qspi *qspi = dev_get_drvdata(dev);
845 
846 	return clk_prepare_enable(qspi->clk);
847 }
848 
849 static int __maybe_unused stm32_qspi_suspend(struct device *dev)
850 {
851 	pinctrl_pm_select_sleep_state(dev);
852 
853 	return pm_runtime_force_suspend(dev);
854 }
855 
856 static int __maybe_unused stm32_qspi_resume(struct device *dev)
857 {
858 	struct stm32_qspi *qspi = dev_get_drvdata(dev);
859 	int ret;
860 
861 	ret = pm_runtime_force_resume(dev);
862 	if (ret < 0)
863 		return ret;
864 
865 	pinctrl_pm_select_default_state(dev);
866 
867 	ret = pm_runtime_get_sync(dev);
868 	if (ret < 0) {
869 		pm_runtime_put_noidle(dev);
870 		return ret;
871 	}
872 
873 	writel_relaxed(qspi->cr_reg, qspi->io_base + QSPI_CR);
874 	writel_relaxed(qspi->dcr_reg, qspi->io_base + QSPI_DCR);
875 
876 	pm_runtime_mark_last_busy(dev);
877 	pm_runtime_put_autosuspend(dev);
878 
879 	return 0;
880 }
881 
882 static const struct dev_pm_ops stm32_qspi_pm_ops = {
883 	SET_RUNTIME_PM_OPS(stm32_qspi_runtime_suspend,
884 			   stm32_qspi_runtime_resume, NULL)
885 	SET_SYSTEM_SLEEP_PM_OPS(stm32_qspi_suspend, stm32_qspi_resume)
886 };
887 
888 static const struct of_device_id stm32_qspi_match[] = {
889 	{.compatible = "st,stm32f469-qspi"},
890 	{}
891 };
892 MODULE_DEVICE_TABLE(of, stm32_qspi_match);
893 
894 static struct platform_driver stm32_qspi_driver = {
895 	.probe	= stm32_qspi_probe,
896 	.remove	= stm32_qspi_remove,
897 	.driver	= {
898 		.name = "stm32-qspi",
899 		.of_match_table = stm32_qspi_match,
900 		.pm = &stm32_qspi_pm_ops,
901 	},
902 };
903 module_platform_driver(stm32_qspi_driver);
904 
905 MODULE_AUTHOR("Ludovic Barre <ludovic.barre@st.com>");
906 MODULE_DESCRIPTION("STMicroelectronics STM32 quad spi driver");
907 MODULE_LICENSE("GPL v2");
908