RISC-V: Fix a race condition during kernel stack overflow
[linux-2.6-microblaze.git] / drivers / spi / spi-stm32-qspi.c
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");