Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
[linux-2.6-microblaze.git] / drivers / spi / spi-fsl-dspi.c
1 // SPDX-License-Identifier: GPL-2.0+
2 //
3 // Copyright 2013 Freescale Semiconductor, Inc.
4 //
5 // Freescale DSPI driver
6 // This file contains a driver for the Freescale DSPI
7
8 #include <linux/clk.h>
9 #include <linux/delay.h>
10 #include <linux/dmaengine.h>
11 #include <linux/dma-mapping.h>
12 #include <linux/interrupt.h>
13 #include <linux/kernel.h>
14 #include <linux/module.h>
15 #include <linux/of_device.h>
16 #include <linux/pinctrl/consumer.h>
17 #include <linux/regmap.h>
18 #include <linux/spi/spi.h>
19 #include <linux/spi/spi-fsl-dspi.h>
20
21 #define DRIVER_NAME                     "fsl-dspi"
22
23 #ifdef CONFIG_M5441x
24 #define DSPI_FIFO_SIZE                  16
25 #else
26 #define DSPI_FIFO_SIZE                  4
27 #endif
28 #define DSPI_DMA_BUFSIZE                (DSPI_FIFO_SIZE * 1024)
29
30 #define SPI_MCR                         0x00
31 #define SPI_MCR_MASTER                  BIT(31)
32 #define SPI_MCR_PCSIS                   (0x3F << 16)
33 #define SPI_MCR_CLR_TXF                 BIT(11)
34 #define SPI_MCR_CLR_RXF                 BIT(10)
35 #define SPI_MCR_XSPI                    BIT(3)
36
37 #define SPI_TCR                         0x08
38 #define SPI_TCR_GET_TCNT(x)             (((x) & GENMASK(31, 16)) >> 16)
39
40 #define SPI_CTAR(x)                     (0x0c + (((x) & GENMASK(1, 0)) * 4))
41 #define SPI_CTAR_FMSZ(x)                (((x) << 27) & GENMASK(30, 27))
42 #define SPI_CTAR_CPOL                   BIT(26)
43 #define SPI_CTAR_CPHA                   BIT(25)
44 #define SPI_CTAR_LSBFE                  BIT(24)
45 #define SPI_CTAR_PCSSCK(x)              (((x) << 22) & GENMASK(23, 22))
46 #define SPI_CTAR_PASC(x)                (((x) << 20) & GENMASK(21, 20))
47 #define SPI_CTAR_PDT(x)                 (((x) << 18) & GENMASK(19, 18))
48 #define SPI_CTAR_PBR(x)                 (((x) << 16) & GENMASK(17, 16))
49 #define SPI_CTAR_CSSCK(x)               (((x) << 12) & GENMASK(15, 12))
50 #define SPI_CTAR_ASC(x)                 (((x) << 8) & GENMASK(11, 8))
51 #define SPI_CTAR_DT(x)                  (((x) << 4) & GENMASK(7, 4))
52 #define SPI_CTAR_BR(x)                  ((x) & GENMASK(3, 0))
53 #define SPI_CTAR_SCALE_BITS             0xf
54
55 #define SPI_CTAR0_SLAVE                 0x0c
56
57 #define SPI_SR                          0x2c
58 #define SPI_SR_TCFQF                    BIT(31)
59 #define SPI_SR_EOQF                     BIT(28)
60 #define SPI_SR_TFUF                     BIT(27)
61 #define SPI_SR_TFFF                     BIT(25)
62 #define SPI_SR_CMDTCF                   BIT(23)
63 #define SPI_SR_SPEF                     BIT(21)
64 #define SPI_SR_RFOF                     BIT(19)
65 #define SPI_SR_TFIWF                    BIT(18)
66 #define SPI_SR_RFDF                     BIT(17)
67 #define SPI_SR_CMDFFF                   BIT(16)
68 #define SPI_SR_CLEAR                    (SPI_SR_TCFQF | SPI_SR_EOQF | \
69                                         SPI_SR_TFUF | SPI_SR_TFFF | \
70                                         SPI_SR_CMDTCF | SPI_SR_SPEF | \
71                                         SPI_SR_RFOF | SPI_SR_TFIWF | \
72                                         SPI_SR_RFDF | SPI_SR_CMDFFF)
73
74 #define SPI_RSER_TFFFE                  BIT(25)
75 #define SPI_RSER_TFFFD                  BIT(24)
76 #define SPI_RSER_RFDFE                  BIT(17)
77 #define SPI_RSER_RFDFD                  BIT(16)
78
79 #define SPI_RSER                        0x30
80 #define SPI_RSER_TCFQE                  BIT(31)
81 #define SPI_RSER_EOQFE                  BIT(28)
82
83 #define SPI_PUSHR                       0x34
84 #define SPI_PUSHR_CMD_CONT              BIT(15)
85 #define SPI_PUSHR_CMD_CTAS(x)           (((x) << 12 & GENMASK(14, 12)))
86 #define SPI_PUSHR_CMD_EOQ               BIT(11)
87 #define SPI_PUSHR_CMD_CTCNT             BIT(10)
88 #define SPI_PUSHR_CMD_PCS(x)            (BIT(x) & GENMASK(5, 0))
89
90 #define SPI_PUSHR_SLAVE                 0x34
91
92 #define SPI_POPR                        0x38
93
94 #define SPI_TXFR0                       0x3c
95 #define SPI_TXFR1                       0x40
96 #define SPI_TXFR2                       0x44
97 #define SPI_TXFR3                       0x48
98 #define SPI_RXFR0                       0x7c
99 #define SPI_RXFR1                       0x80
100 #define SPI_RXFR2                       0x84
101 #define SPI_RXFR3                       0x88
102
103 #define SPI_CTARE(x)                    (0x11c + (((x) & GENMASK(1, 0)) * 4))
104 #define SPI_CTARE_FMSZE(x)              (((x) & 0x1) << 16)
105 #define SPI_CTARE_DTCP(x)               ((x) & 0x7ff)
106
107 #define SPI_SREX                        0x13c
108
109 #define SPI_FRAME_BITS(bits)            SPI_CTAR_FMSZ((bits) - 1)
110 #define SPI_FRAME_EBITS(bits)           SPI_CTARE_FMSZE(((bits) - 1) >> 4)
111
112 /* Register offsets for regmap_pushr */
113 #define PUSHR_CMD                       0x0
114 #define PUSHR_TX                        0x2
115
116 #define DMA_COMPLETION_TIMEOUT          msecs_to_jiffies(3000)
117
118 struct chip_data {
119         u32                     ctar_val;
120         u16                     void_write_data;
121 };
122
123 enum dspi_trans_mode {
124         DSPI_EOQ_MODE = 0,
125         DSPI_TCFQ_MODE,
126         DSPI_DMA_MODE,
127 };
128
129 struct fsl_dspi_devtype_data {
130         enum dspi_trans_mode    trans_mode;
131         u8                      max_clock_factor;
132         bool                    xspi_mode;
133 };
134
135 static const struct fsl_dspi_devtype_data vf610_data = {
136         .trans_mode             = DSPI_DMA_MODE,
137         .max_clock_factor       = 2,
138 };
139
140 static const struct fsl_dspi_devtype_data ls1021a_v1_data = {
141         .trans_mode             = DSPI_TCFQ_MODE,
142         .max_clock_factor       = 8,
143         .xspi_mode              = true,
144 };
145
146 static const struct fsl_dspi_devtype_data ls2085a_data = {
147         .trans_mode             = DSPI_TCFQ_MODE,
148         .max_clock_factor       = 8,
149 };
150
151 static const struct fsl_dspi_devtype_data coldfire_data = {
152         .trans_mode             = DSPI_EOQ_MODE,
153         .max_clock_factor       = 8,
154 };
155
156 struct fsl_dspi_dma {
157         /* Length of transfer in words of DSPI_FIFO_SIZE */
158         u32                                     curr_xfer_len;
159
160         u32                                     *tx_dma_buf;
161         struct dma_chan                         *chan_tx;
162         dma_addr_t                              tx_dma_phys;
163         struct completion                       cmd_tx_complete;
164         struct dma_async_tx_descriptor          *tx_desc;
165
166         u32                                     *rx_dma_buf;
167         struct dma_chan                         *chan_rx;
168         dma_addr_t                              rx_dma_phys;
169         struct completion                       cmd_rx_complete;
170         struct dma_async_tx_descriptor          *rx_desc;
171 };
172
173 struct fsl_dspi {
174         struct spi_controller                   *ctlr;
175         struct platform_device                  *pdev;
176
177         struct regmap                           *regmap;
178         struct regmap                           *regmap_pushr;
179         int                                     irq;
180         struct clk                              *clk;
181
182         struct spi_transfer                     *cur_transfer;
183         struct spi_message                      *cur_msg;
184         struct chip_data                        *cur_chip;
185         size_t                                  len;
186         const void                              *tx;
187         void                                    *rx;
188         void                                    *rx_end;
189         u16                                     void_write_data;
190         u16                                     tx_cmd;
191         u8                                      bits_per_word;
192         u8                                      bytes_per_word;
193         const struct fsl_dspi_devtype_data      *devtype_data;
194
195         wait_queue_head_t                       waitq;
196         u32                                     waitflags;
197
198         struct fsl_dspi_dma                     *dma;
199 };
200
201 static u32 dspi_pop_tx(struct fsl_dspi *dspi)
202 {
203         u32 txdata = 0;
204
205         if (dspi->tx) {
206                 if (dspi->bytes_per_word == 1)
207                         txdata = *(u8 *)dspi->tx;
208                 else if (dspi->bytes_per_word == 2)
209                         txdata = *(u16 *)dspi->tx;
210                 else  /* dspi->bytes_per_word == 4 */
211                         txdata = *(u32 *)dspi->tx;
212                 dspi->tx += dspi->bytes_per_word;
213         }
214         dspi->len -= dspi->bytes_per_word;
215         return txdata;
216 }
217
218 static u32 dspi_pop_tx_pushr(struct fsl_dspi *dspi)
219 {
220         u16 cmd = dspi->tx_cmd, data = dspi_pop_tx(dspi);
221
222         if (spi_controller_is_slave(dspi->ctlr))
223                 return data;
224
225         if (dspi->len > 0)
226                 cmd |= SPI_PUSHR_CMD_CONT;
227         return cmd << 16 | data;
228 }
229
230 static void dspi_push_rx(struct fsl_dspi *dspi, u32 rxdata)
231 {
232         if (!dspi->rx)
233                 return;
234
235         /* Mask off undefined bits */
236         rxdata &= (1 << dspi->bits_per_word) - 1;
237
238         if (dspi->bytes_per_word == 1)
239                 *(u8 *)dspi->rx = rxdata;
240         else if (dspi->bytes_per_word == 2)
241                 *(u16 *)dspi->rx = rxdata;
242         else /* dspi->bytes_per_word == 4 */
243                 *(u32 *)dspi->rx = rxdata;
244         dspi->rx += dspi->bytes_per_word;
245 }
246
247 static void dspi_tx_dma_callback(void *arg)
248 {
249         struct fsl_dspi *dspi = arg;
250         struct fsl_dspi_dma *dma = dspi->dma;
251
252         complete(&dma->cmd_tx_complete);
253 }
254
255 static void dspi_rx_dma_callback(void *arg)
256 {
257         struct fsl_dspi *dspi = arg;
258         struct fsl_dspi_dma *dma = dspi->dma;
259         int i;
260
261         if (dspi->rx) {
262                 for (i = 0; i < dma->curr_xfer_len; i++)
263                         dspi_push_rx(dspi, dspi->dma->rx_dma_buf[i]);
264         }
265
266         complete(&dma->cmd_rx_complete);
267 }
268
269 static int dspi_next_xfer_dma_submit(struct fsl_dspi *dspi)
270 {
271         struct device *dev = &dspi->pdev->dev;
272         struct fsl_dspi_dma *dma = dspi->dma;
273         int time_left;
274         int i;
275
276         for (i = 0; i < dma->curr_xfer_len; i++)
277                 dspi->dma->tx_dma_buf[i] = dspi_pop_tx_pushr(dspi);
278
279         dma->tx_desc = dmaengine_prep_slave_single(dma->chan_tx,
280                                         dma->tx_dma_phys,
281                                         dma->curr_xfer_len *
282                                         DMA_SLAVE_BUSWIDTH_4_BYTES,
283                                         DMA_MEM_TO_DEV,
284                                         DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
285         if (!dma->tx_desc) {
286                 dev_err(dev, "Not able to get desc for DMA xfer\n");
287                 return -EIO;
288         }
289
290         dma->tx_desc->callback = dspi_tx_dma_callback;
291         dma->tx_desc->callback_param = dspi;
292         if (dma_submit_error(dmaengine_submit(dma->tx_desc))) {
293                 dev_err(dev, "DMA submit failed\n");
294                 return -EINVAL;
295         }
296
297         dma->rx_desc = dmaengine_prep_slave_single(dma->chan_rx,
298                                         dma->rx_dma_phys,
299                                         dma->curr_xfer_len *
300                                         DMA_SLAVE_BUSWIDTH_4_BYTES,
301                                         DMA_DEV_TO_MEM,
302                                         DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
303         if (!dma->rx_desc) {
304                 dev_err(dev, "Not able to get desc for DMA xfer\n");
305                 return -EIO;
306         }
307
308         dma->rx_desc->callback = dspi_rx_dma_callback;
309         dma->rx_desc->callback_param = dspi;
310         if (dma_submit_error(dmaengine_submit(dma->rx_desc))) {
311                 dev_err(dev, "DMA submit failed\n");
312                 return -EINVAL;
313         }
314
315         reinit_completion(&dspi->dma->cmd_rx_complete);
316         reinit_completion(&dspi->dma->cmd_tx_complete);
317
318         dma_async_issue_pending(dma->chan_rx);
319         dma_async_issue_pending(dma->chan_tx);
320
321         if (spi_controller_is_slave(dspi->ctlr)) {
322                 wait_for_completion_interruptible(&dspi->dma->cmd_rx_complete);
323                 return 0;
324         }
325
326         time_left = wait_for_completion_timeout(&dspi->dma->cmd_tx_complete,
327                                                 DMA_COMPLETION_TIMEOUT);
328         if (time_left == 0) {
329                 dev_err(dev, "DMA tx timeout\n");
330                 dmaengine_terminate_all(dma->chan_tx);
331                 dmaengine_terminate_all(dma->chan_rx);
332                 return -ETIMEDOUT;
333         }
334
335         time_left = wait_for_completion_timeout(&dspi->dma->cmd_rx_complete,
336                                                 DMA_COMPLETION_TIMEOUT);
337         if (time_left == 0) {
338                 dev_err(dev, "DMA rx timeout\n");
339                 dmaengine_terminate_all(dma->chan_tx);
340                 dmaengine_terminate_all(dma->chan_rx);
341                 return -ETIMEDOUT;
342         }
343
344         return 0;
345 }
346
347 static int dspi_dma_xfer(struct fsl_dspi *dspi)
348 {
349         struct spi_message *message = dspi->cur_msg;
350         struct device *dev = &dspi->pdev->dev;
351         struct fsl_dspi_dma *dma = dspi->dma;
352         int curr_remaining_bytes;
353         int bytes_per_buffer;
354         int ret = 0;
355
356         curr_remaining_bytes = dspi->len;
357         bytes_per_buffer = DSPI_DMA_BUFSIZE / DSPI_FIFO_SIZE;
358         while (curr_remaining_bytes) {
359                 /* Check if current transfer fits the DMA buffer */
360                 dma->curr_xfer_len = curr_remaining_bytes
361                         / dspi->bytes_per_word;
362                 if (dma->curr_xfer_len > bytes_per_buffer)
363                         dma->curr_xfer_len = bytes_per_buffer;
364
365                 ret = dspi_next_xfer_dma_submit(dspi);
366                 if (ret) {
367                         dev_err(dev, "DMA transfer failed\n");
368                         goto exit;
369
370                 } else {
371                         const int len =
372                                 dma->curr_xfer_len * dspi->bytes_per_word;
373                         curr_remaining_bytes -= len;
374                         message->actual_length += len;
375                         if (curr_remaining_bytes < 0)
376                                 curr_remaining_bytes = 0;
377                 }
378         }
379
380 exit:
381         return ret;
382 }
383
384 static int dspi_request_dma(struct fsl_dspi *dspi, phys_addr_t phy_addr)
385 {
386         struct device *dev = &dspi->pdev->dev;
387         struct dma_slave_config cfg;
388         struct fsl_dspi_dma *dma;
389         int ret;
390
391         dma = devm_kzalloc(dev, sizeof(*dma), GFP_KERNEL);
392         if (!dma)
393                 return -ENOMEM;
394
395         dma->chan_rx = dma_request_slave_channel(dev, "rx");
396         if (!dma->chan_rx) {
397                 dev_err(dev, "rx dma channel not available\n");
398                 ret = -ENODEV;
399                 return ret;
400         }
401
402         dma->chan_tx = dma_request_slave_channel(dev, "tx");
403         if (!dma->chan_tx) {
404                 dev_err(dev, "tx dma channel not available\n");
405                 ret = -ENODEV;
406                 goto err_tx_channel;
407         }
408
409         dma->tx_dma_buf = dma_alloc_coherent(dev, DSPI_DMA_BUFSIZE,
410                                              &dma->tx_dma_phys, GFP_KERNEL);
411         if (!dma->tx_dma_buf) {
412                 ret = -ENOMEM;
413                 goto err_tx_dma_buf;
414         }
415
416         dma->rx_dma_buf = dma_alloc_coherent(dev, DSPI_DMA_BUFSIZE,
417                                              &dma->rx_dma_phys, GFP_KERNEL);
418         if (!dma->rx_dma_buf) {
419                 ret = -ENOMEM;
420                 goto err_rx_dma_buf;
421         }
422
423         cfg.src_addr = phy_addr + SPI_POPR;
424         cfg.dst_addr = phy_addr + SPI_PUSHR;
425         cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
426         cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
427         cfg.src_maxburst = 1;
428         cfg.dst_maxburst = 1;
429
430         cfg.direction = DMA_DEV_TO_MEM;
431         ret = dmaengine_slave_config(dma->chan_rx, &cfg);
432         if (ret) {
433                 dev_err(dev, "can't configure rx dma channel\n");
434                 ret = -EINVAL;
435                 goto err_slave_config;
436         }
437
438         cfg.direction = DMA_MEM_TO_DEV;
439         ret = dmaengine_slave_config(dma->chan_tx, &cfg);
440         if (ret) {
441                 dev_err(dev, "can't configure tx dma channel\n");
442                 ret = -EINVAL;
443                 goto err_slave_config;
444         }
445
446         dspi->dma = dma;
447         init_completion(&dma->cmd_tx_complete);
448         init_completion(&dma->cmd_rx_complete);
449
450         return 0;
451
452 err_slave_config:
453         dma_free_coherent(dev, DSPI_DMA_BUFSIZE,
454                         dma->rx_dma_buf, dma->rx_dma_phys);
455 err_rx_dma_buf:
456         dma_free_coherent(dev, DSPI_DMA_BUFSIZE,
457                         dma->tx_dma_buf, dma->tx_dma_phys);
458 err_tx_dma_buf:
459         dma_release_channel(dma->chan_tx);
460 err_tx_channel:
461         dma_release_channel(dma->chan_rx);
462
463         devm_kfree(dev, dma);
464         dspi->dma = NULL;
465
466         return ret;
467 }
468
469 static void dspi_release_dma(struct fsl_dspi *dspi)
470 {
471         struct fsl_dspi_dma *dma = dspi->dma;
472         struct device *dev = &dspi->pdev->dev;
473
474         if (!dma)
475                 return;
476
477         if (dma->chan_tx) {
478                 dma_unmap_single(dev, dma->tx_dma_phys,
479                                  DSPI_DMA_BUFSIZE, DMA_TO_DEVICE);
480                 dma_release_channel(dma->chan_tx);
481         }
482
483         if (dma->chan_rx) {
484                 dma_unmap_single(dev, dma->rx_dma_phys,
485                                  DSPI_DMA_BUFSIZE, DMA_FROM_DEVICE);
486                 dma_release_channel(dma->chan_rx);
487         }
488 }
489
490 static void hz_to_spi_baud(char *pbr, char *br, int speed_hz,
491                            unsigned long clkrate)
492 {
493         /* Valid baud rate pre-scaler values */
494         int pbr_tbl[4] = {2, 3, 5, 7};
495         int brs[16] = { 2,      4,      6,      8,
496                         16,     32,     64,     128,
497                         256,    512,    1024,   2048,
498                         4096,   8192,   16384,  32768 };
499         int scale_needed, scale, minscale = INT_MAX;
500         int i, j;
501
502         scale_needed = clkrate / speed_hz;
503         if (clkrate % speed_hz)
504                 scale_needed++;
505
506         for (i = 0; i < ARRAY_SIZE(brs); i++)
507                 for (j = 0; j < ARRAY_SIZE(pbr_tbl); j++) {
508                         scale = brs[i] * pbr_tbl[j];
509                         if (scale >= scale_needed) {
510                                 if (scale < minscale) {
511                                         minscale = scale;
512                                         *br = i;
513                                         *pbr = j;
514                                 }
515                                 break;
516                         }
517                 }
518
519         if (minscale == INT_MAX) {
520                 pr_warn("Can not find valid baud rate,speed_hz is %d,clkrate is %ld, we use the max prescaler value.\n",
521                         speed_hz, clkrate);
522                 *pbr = ARRAY_SIZE(pbr_tbl) - 1;
523                 *br =  ARRAY_SIZE(brs) - 1;
524         }
525 }
526
527 static void ns_delay_scale(char *psc, char *sc, int delay_ns,
528                            unsigned long clkrate)
529 {
530         int scale_needed, scale, minscale = INT_MAX;
531         int pscale_tbl[4] = {1, 3, 5, 7};
532         u32 remainder;
533         int i, j;
534
535         scale_needed = div_u64_rem((u64)delay_ns * clkrate, NSEC_PER_SEC,
536                                    &remainder);
537         if (remainder)
538                 scale_needed++;
539
540         for (i = 0; i < ARRAY_SIZE(pscale_tbl); i++)
541                 for (j = 0; j <= SPI_CTAR_SCALE_BITS; j++) {
542                         scale = pscale_tbl[i] * (2 << j);
543                         if (scale >= scale_needed) {
544                                 if (scale < minscale) {
545                                         minscale = scale;
546                                         *psc = i;
547                                         *sc = j;
548                                 }
549                                 break;
550                         }
551                 }
552
553         if (minscale == INT_MAX) {
554                 pr_warn("Cannot find correct scale values for %dns delay at clkrate %ld, using max prescaler value",
555                         delay_ns, clkrate);
556                 *psc = ARRAY_SIZE(pscale_tbl) - 1;
557                 *sc = SPI_CTAR_SCALE_BITS;
558         }
559 }
560
561 static void fifo_write(struct fsl_dspi *dspi)
562 {
563         regmap_write(dspi->regmap, SPI_PUSHR, dspi_pop_tx_pushr(dspi));
564 }
565
566 static void cmd_fifo_write(struct fsl_dspi *dspi)
567 {
568         u16 cmd = dspi->tx_cmd;
569
570         if (dspi->len > 0)
571                 cmd |= SPI_PUSHR_CMD_CONT;
572         regmap_write(dspi->regmap_pushr, PUSHR_CMD, cmd);
573 }
574
575 static void tx_fifo_write(struct fsl_dspi *dspi, u16 txdata)
576 {
577         regmap_write(dspi->regmap_pushr, PUSHR_TX, txdata);
578 }
579
580 static void dspi_tcfq_write(struct fsl_dspi *dspi)
581 {
582         /* Clear transfer count */
583         dspi->tx_cmd |= SPI_PUSHR_CMD_CTCNT;
584
585         if (dspi->devtype_data->xspi_mode && dspi->bits_per_word > 16) {
586                 /* Write two TX FIFO entries first, and then the corresponding
587                  * CMD FIFO entry.
588                  */
589                 u32 data = dspi_pop_tx(dspi);
590
591                 if (dspi->cur_chip->ctar_val & SPI_CTAR_LSBFE) {
592                         /* LSB */
593                         tx_fifo_write(dspi, data & 0xFFFF);
594                         tx_fifo_write(dspi, data >> 16);
595                 } else {
596                         /* MSB */
597                         tx_fifo_write(dspi, data >> 16);
598                         tx_fifo_write(dspi, data & 0xFFFF);
599                 }
600                 cmd_fifo_write(dspi);
601         } else {
602                 /* Write one entry to both TX FIFO and CMD FIFO
603                  * simultaneously.
604                  */
605                 fifo_write(dspi);
606         }
607 }
608
609 static u32 fifo_read(struct fsl_dspi *dspi)
610 {
611         u32 rxdata = 0;
612
613         regmap_read(dspi->regmap, SPI_POPR, &rxdata);
614         return rxdata;
615 }
616
617 static void dspi_tcfq_read(struct fsl_dspi *dspi)
618 {
619         dspi_push_rx(dspi, fifo_read(dspi));
620 }
621
622 static void dspi_eoq_write(struct fsl_dspi *dspi)
623 {
624         int fifo_size = DSPI_FIFO_SIZE;
625         u16 xfer_cmd = dspi->tx_cmd;
626
627         /* Fill TX FIFO with as many transfers as possible */
628         while (dspi->len && fifo_size--) {
629                 dspi->tx_cmd = xfer_cmd;
630                 /* Request EOQF for last transfer in FIFO */
631                 if (dspi->len == dspi->bytes_per_word || fifo_size == 0)
632                         dspi->tx_cmd |= SPI_PUSHR_CMD_EOQ;
633                 /* Clear transfer count for first transfer in FIFO */
634                 if (fifo_size == (DSPI_FIFO_SIZE - 1))
635                         dspi->tx_cmd |= SPI_PUSHR_CMD_CTCNT;
636                 /* Write combined TX FIFO and CMD FIFO entry */
637                 fifo_write(dspi);
638         }
639 }
640
641 static void dspi_eoq_read(struct fsl_dspi *dspi)
642 {
643         int fifo_size = DSPI_FIFO_SIZE;
644
645         /* Read one FIFO entry and push to rx buffer */
646         while ((dspi->rx < dspi->rx_end) && fifo_size--)
647                 dspi_push_rx(dspi, fifo_read(dspi));
648 }
649
650 static int dspi_rxtx(struct fsl_dspi *dspi)
651 {
652         struct spi_message *msg = dspi->cur_msg;
653         enum dspi_trans_mode trans_mode;
654         u16 spi_tcnt;
655         u32 spi_tcr;
656
657         /* Get transfer counter (in number of SPI transfers). It was
658          * reset to 0 when transfer(s) were started.
659          */
660         regmap_read(dspi->regmap, SPI_TCR, &spi_tcr);
661         spi_tcnt = SPI_TCR_GET_TCNT(spi_tcr);
662         /* Update total number of bytes that were transferred */
663         msg->actual_length += spi_tcnt * dspi->bytes_per_word;
664
665         trans_mode = dspi->devtype_data->trans_mode;
666         if (trans_mode == DSPI_EOQ_MODE)
667                 dspi_eoq_read(dspi);
668         else if (trans_mode == DSPI_TCFQ_MODE)
669                 dspi_tcfq_read(dspi);
670
671         if (!dspi->len)
672                 /* Success! */
673                 return 0;
674
675         if (trans_mode == DSPI_EOQ_MODE)
676                 dspi_eoq_write(dspi);
677         else if (trans_mode == DSPI_TCFQ_MODE)
678                 dspi_tcfq_write(dspi);
679
680         return -EINPROGRESS;
681 }
682
683 static int dspi_poll(struct fsl_dspi *dspi)
684 {
685         int tries = 1000;
686         u32 spi_sr;
687
688         do {
689                 regmap_read(dspi->regmap, SPI_SR, &spi_sr);
690                 regmap_write(dspi->regmap, SPI_SR, spi_sr);
691
692                 if (spi_sr & (SPI_SR_EOQF | SPI_SR_TCFQF))
693                         break;
694         } while (--tries);
695
696         if (!tries)
697                 return -ETIMEDOUT;
698
699         return dspi_rxtx(dspi);
700 }
701
702 static irqreturn_t dspi_interrupt(int irq, void *dev_id)
703 {
704         struct fsl_dspi *dspi = (struct fsl_dspi *)dev_id;
705         u32 spi_sr;
706
707         regmap_read(dspi->regmap, SPI_SR, &spi_sr);
708         regmap_write(dspi->regmap, SPI_SR, spi_sr);
709
710         if (!(spi_sr & (SPI_SR_EOQF | SPI_SR_TCFQF)))
711                 return IRQ_NONE;
712
713         if (dspi_rxtx(dspi) == 0) {
714                 dspi->waitflags = 1;
715                 wake_up_interruptible(&dspi->waitq);
716         }
717
718         return IRQ_HANDLED;
719 }
720
721 static int dspi_transfer_one_message(struct spi_controller *ctlr,
722                                      struct spi_message *message)
723 {
724         struct fsl_dspi *dspi = spi_controller_get_devdata(ctlr);
725         struct spi_device *spi = message->spi;
726         enum dspi_trans_mode trans_mode;
727         struct spi_transfer *transfer;
728         int status = 0;
729
730         message->actual_length = 0;
731
732         list_for_each_entry(transfer, &message->transfers, transfer_list) {
733                 dspi->cur_transfer = transfer;
734                 dspi->cur_msg = message;
735                 dspi->cur_chip = spi_get_ctldata(spi);
736                 /* Prepare command word for CMD FIFO */
737                 dspi->tx_cmd = SPI_PUSHR_CMD_CTAS(0) |
738                                SPI_PUSHR_CMD_PCS(spi->chip_select);
739                 if (list_is_last(&dspi->cur_transfer->transfer_list,
740                                  &dspi->cur_msg->transfers)) {
741                         /* Leave PCS activated after last transfer when
742                          * cs_change is set.
743                          */
744                         if (transfer->cs_change)
745                                 dspi->tx_cmd |= SPI_PUSHR_CMD_CONT;
746                 } else {
747                         /* Keep PCS active between transfers in same message
748                          * when cs_change is not set, and de-activate PCS
749                          * between transfers in the same message when
750                          * cs_change is set.
751                          */
752                         if (!transfer->cs_change)
753                                 dspi->tx_cmd |= SPI_PUSHR_CMD_CONT;
754                 }
755
756                 dspi->void_write_data = dspi->cur_chip->void_write_data;
757
758                 dspi->tx = transfer->tx_buf;
759                 dspi->rx = transfer->rx_buf;
760                 dspi->rx_end = dspi->rx + transfer->len;
761                 dspi->len = transfer->len;
762                 /* Validated transfer specific frame size (defaults applied) */
763                 dspi->bits_per_word = transfer->bits_per_word;
764                 if (transfer->bits_per_word <= 8)
765                         dspi->bytes_per_word = 1;
766                 else if (transfer->bits_per_word <= 16)
767                         dspi->bytes_per_word = 2;
768                 else
769                         dspi->bytes_per_word = 4;
770
771                 regmap_update_bits(dspi->regmap, SPI_MCR,
772                                    SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF,
773                                    SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF);
774                 regmap_write(dspi->regmap, SPI_CTAR(0),
775                              dspi->cur_chip->ctar_val |
776                              SPI_FRAME_BITS(transfer->bits_per_word));
777                 if (dspi->devtype_data->xspi_mode)
778                         regmap_write(dspi->regmap, SPI_CTARE(0),
779                                      SPI_FRAME_EBITS(transfer->bits_per_word) |
780                                      SPI_CTARE_DTCP(1));
781
782                 trans_mode = dspi->devtype_data->trans_mode;
783                 switch (trans_mode) {
784                 case DSPI_EOQ_MODE:
785                         regmap_write(dspi->regmap, SPI_RSER, SPI_RSER_EOQFE);
786                         dspi_eoq_write(dspi);
787                         break;
788                 case DSPI_TCFQ_MODE:
789                         regmap_write(dspi->regmap, SPI_RSER, SPI_RSER_TCFQE);
790                         dspi_tcfq_write(dspi);
791                         break;
792                 case DSPI_DMA_MODE:
793                         regmap_write(dspi->regmap, SPI_RSER,
794                                      SPI_RSER_TFFFE | SPI_RSER_TFFFD |
795                                      SPI_RSER_RFDFE | SPI_RSER_RFDFD);
796                         status = dspi_dma_xfer(dspi);
797                         break;
798                 default:
799                         dev_err(&dspi->pdev->dev, "unsupported trans_mode %u\n",
800                                 trans_mode);
801                         status = -EINVAL;
802                         goto out;
803                 }
804
805                 if (!dspi->irq) {
806                         do {
807                                 status = dspi_poll(dspi);
808                         } while (status == -EINPROGRESS);
809                 } else if (trans_mode != DSPI_DMA_MODE) {
810                         status = wait_event_interruptible(dspi->waitq,
811                                                           dspi->waitflags);
812                         dspi->waitflags = 0;
813                 }
814                 if (status)
815                         dev_err(&dspi->pdev->dev,
816                                 "Waiting for transfer to complete failed!\n");
817
818                 if (transfer->delay_usecs)
819                         udelay(transfer->delay_usecs);
820         }
821
822 out:
823         message->status = status;
824         spi_finalize_current_message(ctlr);
825
826         return status;
827 }
828
829 static int dspi_setup(struct spi_device *spi)
830 {
831         struct fsl_dspi *dspi = spi_controller_get_devdata(spi->controller);
832         unsigned char br = 0, pbr = 0, pcssck = 0, cssck = 0;
833         u32 cs_sck_delay = 0, sck_cs_delay = 0;
834         struct fsl_dspi_platform_data *pdata;
835         unsigned char pasc = 0, asc = 0;
836         struct chip_data *chip;
837         unsigned long clkrate;
838
839         /* Only alloc on first setup */
840         chip = spi_get_ctldata(spi);
841         if (chip == NULL) {
842                 chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
843                 if (!chip)
844                         return -ENOMEM;
845         }
846
847         pdata = dev_get_platdata(&dspi->pdev->dev);
848
849         if (!pdata) {
850                 of_property_read_u32(spi->dev.of_node, "fsl,spi-cs-sck-delay",
851                                      &cs_sck_delay);
852
853                 of_property_read_u32(spi->dev.of_node, "fsl,spi-sck-cs-delay",
854                                      &sck_cs_delay);
855         } else {
856                 cs_sck_delay = pdata->cs_sck_delay;
857                 sck_cs_delay = pdata->sck_cs_delay;
858         }
859
860         chip->void_write_data = 0;
861
862         clkrate = clk_get_rate(dspi->clk);
863         hz_to_spi_baud(&pbr, &br, spi->max_speed_hz, clkrate);
864
865         /* Set PCS to SCK delay scale values */
866         ns_delay_scale(&pcssck, &cssck, cs_sck_delay, clkrate);
867
868         /* Set After SCK delay scale values */
869         ns_delay_scale(&pasc, &asc, sck_cs_delay, clkrate);
870
871         chip->ctar_val = 0;
872         if (spi->mode & SPI_CPOL)
873                 chip->ctar_val |= SPI_CTAR_CPOL;
874         if (spi->mode & SPI_CPHA)
875                 chip->ctar_val |= SPI_CTAR_CPHA;
876
877         if (!spi_controller_is_slave(dspi->ctlr)) {
878                 chip->ctar_val |= SPI_CTAR_PCSSCK(pcssck) |
879                                   SPI_CTAR_CSSCK(cssck) |
880                                   SPI_CTAR_PASC(pasc) |
881                                   SPI_CTAR_ASC(asc) |
882                                   SPI_CTAR_PBR(pbr) |
883                                   SPI_CTAR_BR(br);
884
885                 if (spi->mode & SPI_LSB_FIRST)
886                         chip->ctar_val |= SPI_CTAR_LSBFE;
887         }
888
889         spi_set_ctldata(spi, chip);
890
891         return 0;
892 }
893
894 static void dspi_cleanup(struct spi_device *spi)
895 {
896         struct chip_data *chip = spi_get_ctldata((struct spi_device *)spi);
897
898         dev_dbg(&spi->dev, "spi_device %u.%u cleanup\n",
899                 spi->controller->bus_num, spi->chip_select);
900
901         kfree(chip);
902 }
903
904 static const struct of_device_id fsl_dspi_dt_ids[] = {
905         { .compatible = "fsl,vf610-dspi", .data = &vf610_data, },
906         { .compatible = "fsl,ls1021a-v1.0-dspi", .data = &ls1021a_v1_data, },
907         { .compatible = "fsl,ls2085a-dspi", .data = &ls2085a_data, },
908         { /* sentinel */ }
909 };
910 MODULE_DEVICE_TABLE(of, fsl_dspi_dt_ids);
911
912 #ifdef CONFIG_PM_SLEEP
913 static int dspi_suspend(struct device *dev)
914 {
915         struct spi_controller *ctlr = dev_get_drvdata(dev);
916         struct fsl_dspi *dspi = spi_controller_get_devdata(ctlr);
917
918         spi_controller_suspend(ctlr);
919         clk_disable_unprepare(dspi->clk);
920
921         pinctrl_pm_select_sleep_state(dev);
922
923         return 0;
924 }
925
926 static int dspi_resume(struct device *dev)
927 {
928         struct spi_controller *ctlr = dev_get_drvdata(dev);
929         struct fsl_dspi *dspi = spi_controller_get_devdata(ctlr);
930         int ret;
931
932         pinctrl_pm_select_default_state(dev);
933
934         ret = clk_prepare_enable(dspi->clk);
935         if (ret)
936                 return ret;
937         spi_controller_resume(ctlr);
938
939         return 0;
940 }
941 #endif /* CONFIG_PM_SLEEP */
942
943 static SIMPLE_DEV_PM_OPS(dspi_pm, dspi_suspend, dspi_resume);
944
945 static const struct regmap_range dspi_volatile_ranges[] = {
946         regmap_reg_range(SPI_MCR, SPI_TCR),
947         regmap_reg_range(SPI_SR, SPI_SR),
948         regmap_reg_range(SPI_PUSHR, SPI_RXFR3),
949 };
950
951 static const struct regmap_access_table dspi_volatile_table = {
952         .yes_ranges     = dspi_volatile_ranges,
953         .n_yes_ranges   = ARRAY_SIZE(dspi_volatile_ranges),
954 };
955
956 static const struct regmap_config dspi_regmap_config = {
957         .reg_bits       = 32,
958         .val_bits       = 32,
959         .reg_stride     = 4,
960         .max_register   = 0x88,
961         .volatile_table = &dspi_volatile_table,
962 };
963
964 static const struct regmap_range dspi_xspi_volatile_ranges[] = {
965         regmap_reg_range(SPI_MCR, SPI_TCR),
966         regmap_reg_range(SPI_SR, SPI_SR),
967         regmap_reg_range(SPI_PUSHR, SPI_RXFR3),
968         regmap_reg_range(SPI_SREX, SPI_SREX),
969 };
970
971 static const struct regmap_access_table dspi_xspi_volatile_table = {
972         .yes_ranges     = dspi_xspi_volatile_ranges,
973         .n_yes_ranges   = ARRAY_SIZE(dspi_xspi_volatile_ranges),
974 };
975
976 static const struct regmap_config dspi_xspi_regmap_config[] = {
977         {
978                 .reg_bits       = 32,
979                 .val_bits       = 32,
980                 .reg_stride     = 4,
981                 .max_register   = 0x13c,
982                 .volatile_table = &dspi_xspi_volatile_table,
983         },
984         {
985                 .name           = "pushr",
986                 .reg_bits       = 16,
987                 .val_bits       = 16,
988                 .reg_stride     = 2,
989                 .max_register   = 0x2,
990         },
991 };
992
993 static void dspi_init(struct fsl_dspi *dspi)
994 {
995         unsigned int mcr = SPI_MCR_PCSIS;
996
997         if (dspi->devtype_data->xspi_mode)
998                 mcr |= SPI_MCR_XSPI;
999         if (!spi_controller_is_slave(dspi->ctlr))
1000                 mcr |= SPI_MCR_MASTER;
1001
1002         regmap_write(dspi->regmap, SPI_MCR, mcr);
1003         regmap_write(dspi->regmap, SPI_SR, SPI_SR_CLEAR);
1004         if (dspi->devtype_data->xspi_mode)
1005                 regmap_write(dspi->regmap, SPI_CTARE(0),
1006                              SPI_CTARE_FMSZE(0) | SPI_CTARE_DTCP(1));
1007 }
1008
1009 static int dspi_probe(struct platform_device *pdev)
1010 {
1011         struct device_node *np = pdev->dev.of_node;
1012         const struct regmap_config *regmap_config;
1013         struct fsl_dspi_platform_data *pdata;
1014         struct spi_controller *ctlr;
1015         int ret, cs_num, bus_num;
1016         struct fsl_dspi *dspi;
1017         struct resource *res;
1018         void __iomem *base;
1019
1020         ctlr = spi_alloc_master(&pdev->dev, sizeof(struct fsl_dspi));
1021         if (!ctlr)
1022                 return -ENOMEM;
1023
1024         dspi = spi_controller_get_devdata(ctlr);
1025         dspi->pdev = pdev;
1026         dspi->ctlr = ctlr;
1027
1028         ctlr->setup = dspi_setup;
1029         ctlr->transfer_one_message = dspi_transfer_one_message;
1030         ctlr->dev.of_node = pdev->dev.of_node;
1031
1032         ctlr->cleanup = dspi_cleanup;
1033         ctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;
1034
1035         pdata = dev_get_platdata(&pdev->dev);
1036         if (pdata) {
1037                 ctlr->num_chipselect = pdata->cs_num;
1038                 ctlr->bus_num = pdata->bus_num;
1039
1040                 dspi->devtype_data = &coldfire_data;
1041         } else {
1042
1043                 ret = of_property_read_u32(np, "spi-num-chipselects", &cs_num);
1044                 if (ret < 0) {
1045                         dev_err(&pdev->dev, "can't get spi-num-chipselects\n");
1046                         goto out_ctlr_put;
1047                 }
1048                 ctlr->num_chipselect = cs_num;
1049
1050                 ret = of_property_read_u32(np, "bus-num", &bus_num);
1051                 if (ret < 0) {
1052                         dev_err(&pdev->dev, "can't get bus-num\n");
1053                         goto out_ctlr_put;
1054                 }
1055                 ctlr->bus_num = bus_num;
1056
1057                 if (of_property_read_bool(np, "spi-slave"))
1058                         ctlr->slave = true;
1059
1060                 dspi->devtype_data = of_device_get_match_data(&pdev->dev);
1061                 if (!dspi->devtype_data) {
1062                         dev_err(&pdev->dev, "can't get devtype_data\n");
1063                         ret = -EFAULT;
1064                         goto out_ctlr_put;
1065                 }
1066         }
1067
1068         if (dspi->devtype_data->xspi_mode)
1069                 ctlr->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1070         else
1071                 ctlr->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16);
1072
1073         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1074         base = devm_ioremap_resource(&pdev->dev, res);
1075         if (IS_ERR(base)) {
1076                 ret = PTR_ERR(base);
1077                 goto out_ctlr_put;
1078         }
1079
1080         if (dspi->devtype_data->xspi_mode)
1081                 regmap_config = &dspi_xspi_regmap_config[0];
1082         else
1083                 regmap_config = &dspi_regmap_config;
1084         dspi->regmap = devm_regmap_init_mmio(&pdev->dev, base, regmap_config);
1085         if (IS_ERR(dspi->regmap)) {
1086                 dev_err(&pdev->dev, "failed to init regmap: %ld\n",
1087                                 PTR_ERR(dspi->regmap));
1088                 ret = PTR_ERR(dspi->regmap);
1089                 goto out_ctlr_put;
1090         }
1091
1092         if (dspi->devtype_data->xspi_mode) {
1093                 dspi->regmap_pushr = devm_regmap_init_mmio(
1094                         &pdev->dev, base + SPI_PUSHR,
1095                         &dspi_xspi_regmap_config[1]);
1096                 if (IS_ERR(dspi->regmap_pushr)) {
1097                         dev_err(&pdev->dev,
1098                                 "failed to init pushr regmap: %ld\n",
1099                                 PTR_ERR(dspi->regmap_pushr));
1100                         ret = PTR_ERR(dspi->regmap_pushr);
1101                         goto out_ctlr_put;
1102                 }
1103         }
1104
1105         dspi->clk = devm_clk_get(&pdev->dev, "dspi");
1106         if (IS_ERR(dspi->clk)) {
1107                 ret = PTR_ERR(dspi->clk);
1108                 dev_err(&pdev->dev, "unable to get clock\n");
1109                 goto out_ctlr_put;
1110         }
1111         ret = clk_prepare_enable(dspi->clk);
1112         if (ret)
1113                 goto out_ctlr_put;
1114
1115         dspi_init(dspi);
1116
1117         dspi->irq = platform_get_irq(pdev, 0);
1118         if (dspi->irq <= 0) {
1119                 dev_info(&pdev->dev,
1120                          "can't get platform irq, using poll mode\n");
1121                 dspi->irq = 0;
1122                 goto poll_mode;
1123         }
1124
1125         ret = devm_request_irq(&pdev->dev, dspi->irq, dspi_interrupt,
1126                                IRQF_SHARED, pdev->name, dspi);
1127         if (ret < 0) {
1128                 dev_err(&pdev->dev, "Unable to attach DSPI interrupt\n");
1129                 goto out_clk_put;
1130         }
1131
1132         init_waitqueue_head(&dspi->waitq);
1133
1134 poll_mode:
1135         if (dspi->devtype_data->trans_mode == DSPI_DMA_MODE) {
1136                 ret = dspi_request_dma(dspi, res->start);
1137                 if (ret < 0) {
1138                         dev_err(&pdev->dev, "can't get dma channels\n");
1139                         goto out_clk_put;
1140                 }
1141         }
1142
1143         ctlr->max_speed_hz =
1144                 clk_get_rate(dspi->clk) / dspi->devtype_data->max_clock_factor;
1145
1146         platform_set_drvdata(pdev, ctlr);
1147
1148         ret = spi_register_controller(ctlr);
1149         if (ret != 0) {
1150                 dev_err(&pdev->dev, "Problem registering DSPI ctlr\n");
1151                 goto out_clk_put;
1152         }
1153
1154         return ret;
1155
1156 out_clk_put:
1157         clk_disable_unprepare(dspi->clk);
1158 out_ctlr_put:
1159         spi_controller_put(ctlr);
1160
1161         return ret;
1162 }
1163
1164 static int dspi_remove(struct platform_device *pdev)
1165 {
1166         struct spi_controller *ctlr = platform_get_drvdata(pdev);
1167         struct fsl_dspi *dspi = spi_controller_get_devdata(ctlr);
1168
1169         /* Disconnect from the SPI framework */
1170         dspi_release_dma(dspi);
1171         clk_disable_unprepare(dspi->clk);
1172         spi_unregister_controller(dspi->ctlr);
1173
1174         return 0;
1175 }
1176
1177 static struct platform_driver fsl_dspi_driver = {
1178         .driver.name            = DRIVER_NAME,
1179         .driver.of_match_table  = fsl_dspi_dt_ids,
1180         .driver.owner           = THIS_MODULE,
1181         .driver.pm              = &dspi_pm,
1182         .probe                  = dspi_probe,
1183         .remove                 = dspi_remove,
1184 };
1185 module_platform_driver(fsl_dspi_driver);
1186
1187 MODULE_DESCRIPTION("Freescale DSPI Controller Driver");
1188 MODULE_LICENSE("GPL");
1189 MODULE_ALIAS("platform:" DRIVER_NAME);