1 // SPDX-License-Identifier: GPL-2.0+
2 //
3 // Copyright 2013 Freescale Semiconductor, Inc.
4 // Copyright 2020 NXP
5 //
6 // Freescale DSPI driver
7 // This file contains a driver for the Freescale DSPI
8
9 #include <linux/clk.h>
10 #include <linux/delay.h>
11 #include <linux/dmaengine.h>
12 #include <linux/dma-mapping.h>
13 #include <linux/interrupt.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/of.h>
17 #include <linux/platform_device.h>
18 #include <linux/pinctrl/consumer.h>
19 #include <linux/regmap.h>
20 #include <linux/spi/spi.h>
21 #include <linux/spi/spi-fsl-dspi.h>
22
23 #define DRIVER_NAME "fsl-dspi"
24
25 #define SPI_MCR 0x00
26 #define SPI_MCR_HOST BIT(31)
27 #define SPI_MCR_PCSIS(x) ((x) << 16)
28 #define SPI_MCR_CLR_TXF BIT(11)
29 #define SPI_MCR_CLR_RXF BIT(10)
30 #define SPI_MCR_XSPI BIT(3)
31 #define SPI_MCR_DIS_TXF BIT(13)
32 #define SPI_MCR_DIS_RXF BIT(12)
33 #define SPI_MCR_HALT BIT(0)
34
35 #define SPI_TCR 0x08
36 #define SPI_TCR_GET_TCNT(x) (((x) & GENMASK(31, 16)) >> 16)
37
38 #define SPI_CTAR(x) (0x0c + (((x) & GENMASK(1, 0)) * 4))
39 #define SPI_CTAR_FMSZ(x) (((x) << 27) & GENMASK(30, 27))
40 #define SPI_CTAR_CPOL BIT(26)
41 #define SPI_CTAR_CPHA BIT(25)
42 #define SPI_CTAR_LSBFE BIT(24)
43 #define SPI_CTAR_PCSSCK(x) (((x) << 22) & GENMASK(23, 22))
44 #define SPI_CTAR_PASC(x) (((x) << 20) & GENMASK(21, 20))
45 #define SPI_CTAR_PDT(x) (((x) << 18) & GENMASK(19, 18))
46 #define SPI_CTAR_PBR(x) (((x) << 16) & GENMASK(17, 16))
47 #define SPI_CTAR_CSSCK(x) (((x) << 12) & GENMASK(15, 12))
48 #define SPI_CTAR_ASC(x) (((x) << 8) & GENMASK(11, 8))
49 #define SPI_CTAR_DT(x) (((x) << 4) & GENMASK(7, 4))
50 #define SPI_CTAR_BR(x) ((x) & GENMASK(3, 0))
51 #define SPI_CTAR_SCALE_BITS 0xf
52
53 #define SPI_CTAR0_SLAVE 0x0c
54
55 #define SPI_SR 0x2c
56 #define SPI_SR_TCFQF BIT(31)
57 #define SPI_SR_TFUF BIT(27)
58 #define SPI_SR_TFFF BIT(25)
59 #define SPI_SR_CMDTCF BIT(23)
60 #define SPI_SR_SPEF BIT(21)
61 #define SPI_SR_RFOF BIT(19)
62 #define SPI_SR_TFIWF BIT(18)
63 #define SPI_SR_RFDF BIT(17)
64 #define SPI_SR_CMDFFF BIT(16)
65 #define SPI_SR_CLEAR (SPI_SR_TCFQF | \
66 SPI_SR_TFUF | SPI_SR_TFFF | \
67 SPI_SR_CMDTCF | SPI_SR_SPEF | \
68 SPI_SR_RFOF | SPI_SR_TFIWF | \
69 SPI_SR_RFDF | SPI_SR_CMDFFF)
70
71 #define SPI_RSER_TFFFE BIT(25)
72 #define SPI_RSER_TFFFD BIT(24)
73 #define SPI_RSER_RFDFE BIT(17)
74 #define SPI_RSER_RFDFD BIT(16)
75
76 #define SPI_RSER 0x30
77 #define SPI_RSER_TCFQE BIT(31)
78 #define SPI_RSER_CMDTCFE BIT(23)
79
80 #define SPI_PUSHR 0x34
81 #define SPI_PUSHR_CMD_CONT BIT(15)
82 #define SPI_PUSHR_CMD_CTAS(x) (((x) << 12 & GENMASK(14, 12)))
83 #define SPI_PUSHR_CMD_EOQ BIT(11)
84 #define SPI_PUSHR_CMD_CTCNT BIT(10)
85 #define SPI_PUSHR_CMD_PCS(x) (BIT(x) & GENMASK(5, 0))
86
87 #define SPI_PUSHR_SLAVE 0x34
88
89 #define SPI_POPR 0x38
90
91 #define SPI_TXFR0 0x3c
92 #define SPI_TXFR1 0x40
93 #define SPI_TXFR2 0x44
94 #define SPI_TXFR3 0x48
95 #define SPI_RXFR0 0x7c
96 #define SPI_RXFR1 0x80
97 #define SPI_RXFR2 0x84
98 #define SPI_RXFR3 0x88
99
100 #define SPI_CTARE(x) (0x11c + (((x) & GENMASK(1, 0)) * 4))
101 #define SPI_CTARE_FMSZE(x) (((x) & 0x1) << 16)
102 #define SPI_CTARE_DTCP(x) ((x) & 0x7ff)
103
104 #define SPI_SREX 0x13c
105
106 #define SPI_FRAME_BITS(bits) SPI_CTAR_FMSZ((bits) - 1)
107 #define SPI_FRAME_EBITS(bits) SPI_CTARE_FMSZE(((bits) - 1) >> 4)
108
109 #define DMA_COMPLETION_TIMEOUT msecs_to_jiffies(3000)
110
111 struct chip_data {
112 u32 ctar_val;
113 };
114
115 enum dspi_trans_mode {
116 DSPI_XSPI_MODE,
117 DSPI_DMA_MODE,
118 };
119
120 struct fsl_dspi_devtype_data {
121 enum dspi_trans_mode trans_mode;
122 u8 max_clock_factor;
123 int fifo_size;
124 };
125
126 enum {
127 LS1021A,
128 LS1012A,
129 LS1028A,
130 LS1043A,
131 LS1046A,
132 LS2080A,
133 LS2085A,
134 LX2160A,
135 MCF5441X,
136 VF610,
137 };
138
139 static const struct fsl_dspi_devtype_data devtype_data[] = {
140 [VF610] = {
141 .trans_mode = DSPI_DMA_MODE,
142 .max_clock_factor = 2,
143 .fifo_size = 4,
144 },
145 [LS1021A] = {
146 /* Has A-011218 DMA erratum */
147 .trans_mode = DSPI_XSPI_MODE,
148 .max_clock_factor = 8,
149 .fifo_size = 4,
150 },
151 [LS1012A] = {
152 /* Has A-011218 DMA erratum */
153 .trans_mode = DSPI_XSPI_MODE,
154 .max_clock_factor = 8,
155 .fifo_size = 16,
156 },
157 [LS1028A] = {
158 .trans_mode = DSPI_XSPI_MODE,
159 .max_clock_factor = 8,
160 .fifo_size = 4,
161 },
162 [LS1043A] = {
163 /* Has A-011218 DMA erratum */
164 .trans_mode = DSPI_XSPI_MODE,
165 .max_clock_factor = 8,
166 .fifo_size = 16,
167 },
168 [LS1046A] = {
169 /* Has A-011218 DMA erratum */
170 .trans_mode = DSPI_XSPI_MODE,
171 .max_clock_factor = 8,
172 .fifo_size = 16,
173 },
174 [LS2080A] = {
175 .trans_mode = DSPI_XSPI_MODE,
176 .max_clock_factor = 8,
177 .fifo_size = 4,
178 },
179 [LS2085A] = {
180 .trans_mode = DSPI_XSPI_MODE,
181 .max_clock_factor = 8,
182 .fifo_size = 4,
183 },
184 [LX2160A] = {
185 .trans_mode = DSPI_XSPI_MODE,
186 .max_clock_factor = 8,
187 .fifo_size = 4,
188 },
189 [MCF5441X] = {
190 .trans_mode = DSPI_DMA_MODE,
191 .max_clock_factor = 8,
192 .fifo_size = 16,
193 },
194 };
195
196 struct fsl_dspi_dma {
197 u32 *tx_dma_buf;
198 struct dma_chan *chan_tx;
199 dma_addr_t tx_dma_phys;
200 struct completion cmd_tx_complete;
201 struct dma_async_tx_descriptor *tx_desc;
202
203 u32 *rx_dma_buf;
204 struct dma_chan *chan_rx;
205 dma_addr_t rx_dma_phys;
206 struct completion cmd_rx_complete;
207 struct dma_async_tx_descriptor *rx_desc;
208 };
209
210 struct fsl_dspi {
211 struct spi_controller *ctlr;
212 struct platform_device *pdev;
213
214 struct regmap *regmap;
215 struct regmap *regmap_pushr;
216 int irq;
217 struct clk *clk;
218
219 struct spi_transfer *cur_transfer;
220 struct spi_message *cur_msg;
221 struct chip_data *cur_chip;
222 size_t progress;
223 size_t len;
224 const void *tx;
225 void *rx;
226 u16 tx_cmd;
227 const struct fsl_dspi_devtype_data *devtype_data;
228
229 struct completion xfer_done;
230
231 struct fsl_dspi_dma *dma;
232
233 int oper_word_size;
234 int oper_bits_per_word;
235
236 int words_in_flight;
237
238 /*
239 * Offsets for CMD and TXDATA within SPI_PUSHR when accessed
240 * individually (in XSPI mode)
241 */
242 int pushr_cmd;
243 int pushr_tx;
244
245 void (*host_to_dev)(struct fsl_dspi *dspi, u32 *txdata);
246 void (*dev_to_host)(struct fsl_dspi *dspi, u32 rxdata);
247 };
248
dspi_native_host_to_dev(struct fsl_dspi * dspi,u32 * txdata)249 static void dspi_native_host_to_dev(struct fsl_dspi *dspi, u32 *txdata)
250 {
251 switch (dspi->oper_word_size) {
252 case 1:
253 *txdata = *(u8 *)dspi->tx;
254 break;
255 case 2:
256 *txdata = *(u16 *)dspi->tx;
257 break;
258 case 4:
259 *txdata = *(u32 *)dspi->tx;
260 break;
261 }
262 dspi->tx += dspi->oper_word_size;
263 }
264
dspi_native_dev_to_host(struct fsl_dspi * dspi,u32 rxdata)265 static void dspi_native_dev_to_host(struct fsl_dspi *dspi, u32 rxdata)
266 {
267 switch (dspi->oper_word_size) {
268 case 1:
269 *(u8 *)dspi->rx = rxdata;
270 break;
271 case 2:
272 *(u16 *)dspi->rx = rxdata;
273 break;
274 case 4:
275 *(u32 *)dspi->rx = rxdata;
276 break;
277 }
278 dspi->rx += dspi->oper_word_size;
279 }
280
dspi_8on32_host_to_dev(struct fsl_dspi * dspi,u32 * txdata)281 static void dspi_8on32_host_to_dev(struct fsl_dspi *dspi, u32 *txdata)
282 {
283 *txdata = cpu_to_be32(*(u32 *)dspi->tx);
284 dspi->tx += sizeof(u32);
285 }
286
dspi_8on32_dev_to_host(struct fsl_dspi * dspi,u32 rxdata)287 static void dspi_8on32_dev_to_host(struct fsl_dspi *dspi, u32 rxdata)
288 {
289 *(u32 *)dspi->rx = be32_to_cpu(rxdata);
290 dspi->rx += sizeof(u32);
291 }
292
dspi_8on16_host_to_dev(struct fsl_dspi * dspi,u32 * txdata)293 static void dspi_8on16_host_to_dev(struct fsl_dspi *dspi, u32 *txdata)
294 {
295 *txdata = cpu_to_be16(*(u16 *)dspi->tx);
296 dspi->tx += sizeof(u16);
297 }
298
dspi_8on16_dev_to_host(struct fsl_dspi * dspi,u32 rxdata)299 static void dspi_8on16_dev_to_host(struct fsl_dspi *dspi, u32 rxdata)
300 {
301 *(u16 *)dspi->rx = be16_to_cpu(rxdata);
302 dspi->rx += sizeof(u16);
303 }
304
dspi_16on32_host_to_dev(struct fsl_dspi * dspi,u32 * txdata)305 static void dspi_16on32_host_to_dev(struct fsl_dspi *dspi, u32 *txdata)
306 {
307 u16 hi = *(u16 *)dspi->tx;
308 u16 lo = *(u16 *)(dspi->tx + 2);
309
310 *txdata = (u32)hi << 16 | lo;
311 dspi->tx += sizeof(u32);
312 }
313
dspi_16on32_dev_to_host(struct fsl_dspi * dspi,u32 rxdata)314 static void dspi_16on32_dev_to_host(struct fsl_dspi *dspi, u32 rxdata)
315 {
316 u16 hi = rxdata & 0xffff;
317 u16 lo = rxdata >> 16;
318
319 *(u16 *)dspi->rx = lo;
320 *(u16 *)(dspi->rx + 2) = hi;
321 dspi->rx += sizeof(u32);
322 }
323
324 /*
325 * Pop one word from the TX buffer for pushing into the
326 * PUSHR register (TX FIFO)
327 */
dspi_pop_tx(struct fsl_dspi * dspi)328 static u32 dspi_pop_tx(struct fsl_dspi *dspi)
329 {
330 u32 txdata = 0;
331
332 if (dspi->tx)
333 dspi->host_to_dev(dspi, &txdata);
334 dspi->len -= dspi->oper_word_size;
335 return txdata;
336 }
337
338 /* Prepare one TX FIFO entry (txdata plus cmd) */
dspi_pop_tx_pushr(struct fsl_dspi * dspi)339 static u32 dspi_pop_tx_pushr(struct fsl_dspi *dspi)
340 {
341 u16 cmd = dspi->tx_cmd, data = dspi_pop_tx(dspi);
342
343 if (spi_controller_is_target(dspi->ctlr))
344 return data;
345
346 if (dspi->len > 0)
347 cmd |= SPI_PUSHR_CMD_CONT;
348 return cmd << 16 | data;
349 }
350
351 /* Push one word to the RX buffer from the POPR register (RX FIFO) */
dspi_push_rx(struct fsl_dspi * dspi,u32 rxdata)352 static void dspi_push_rx(struct fsl_dspi *dspi, u32 rxdata)
353 {
354 if (!dspi->rx)
355 return;
356 dspi->dev_to_host(dspi, rxdata);
357 }
358
dspi_tx_dma_callback(void * arg)359 static void dspi_tx_dma_callback(void *arg)
360 {
361 struct fsl_dspi *dspi = arg;
362 struct fsl_dspi_dma *dma = dspi->dma;
363
364 complete(&dma->cmd_tx_complete);
365 }
366
dspi_rx_dma_callback(void * arg)367 static void dspi_rx_dma_callback(void *arg)
368 {
369 struct fsl_dspi *dspi = arg;
370 struct fsl_dspi_dma *dma = dspi->dma;
371 int i;
372
373 if (dspi->rx) {
374 for (i = 0; i < dspi->words_in_flight; i++)
375 dspi_push_rx(dspi, dspi->dma->rx_dma_buf[i]);
376 }
377
378 complete(&dma->cmd_rx_complete);
379 }
380
dspi_next_xfer_dma_submit(struct fsl_dspi * dspi)381 static int dspi_next_xfer_dma_submit(struct fsl_dspi *dspi)
382 {
383 struct device *dev = &dspi->pdev->dev;
384 struct fsl_dspi_dma *dma = dspi->dma;
385 int time_left;
386 int i;
387
388 for (i = 0; i < dspi->words_in_flight; i++)
389 dspi->dma->tx_dma_buf[i] = dspi_pop_tx_pushr(dspi);
390
391 dma->tx_desc = dmaengine_prep_slave_single(dma->chan_tx,
392 dma->tx_dma_phys,
393 dspi->words_in_flight *
394 DMA_SLAVE_BUSWIDTH_4_BYTES,
395 DMA_MEM_TO_DEV,
396 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
397 if (!dma->tx_desc) {
398 dev_err(dev, "Not able to get desc for DMA xfer\n");
399 return -EIO;
400 }
401
402 dma->tx_desc->callback = dspi_tx_dma_callback;
403 dma->tx_desc->callback_param = dspi;
404 if (dma_submit_error(dmaengine_submit(dma->tx_desc))) {
405 dev_err(dev, "DMA submit failed\n");
406 return -EINVAL;
407 }
408
409 dma->rx_desc = dmaengine_prep_slave_single(dma->chan_rx,
410 dma->rx_dma_phys,
411 dspi->words_in_flight *
412 DMA_SLAVE_BUSWIDTH_4_BYTES,
413 DMA_DEV_TO_MEM,
414 DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
415 if (!dma->rx_desc) {
416 dev_err(dev, "Not able to get desc for DMA xfer\n");
417 return -EIO;
418 }
419
420 dma->rx_desc->callback = dspi_rx_dma_callback;
421 dma->rx_desc->callback_param = dspi;
422 if (dma_submit_error(dmaengine_submit(dma->rx_desc))) {
423 dev_err(dev, "DMA submit failed\n");
424 return -EINVAL;
425 }
426
427 reinit_completion(&dspi->dma->cmd_rx_complete);
428 reinit_completion(&dspi->dma->cmd_tx_complete);
429
430 dma_async_issue_pending(dma->chan_rx);
431 dma_async_issue_pending(dma->chan_tx);
432
433 if (spi_controller_is_target(dspi->ctlr)) {
434 wait_for_completion_interruptible(&dspi->dma->cmd_rx_complete);
435 return 0;
436 }
437
438 time_left = wait_for_completion_timeout(&dspi->dma->cmd_tx_complete,
439 DMA_COMPLETION_TIMEOUT);
440 if (time_left == 0) {
441 dev_err(dev, "DMA tx timeout\n");
442 dmaengine_terminate_all(dma->chan_tx);
443 dmaengine_terminate_all(dma->chan_rx);
444 return -ETIMEDOUT;
445 }
446
447 time_left = wait_for_completion_timeout(&dspi->dma->cmd_rx_complete,
448 DMA_COMPLETION_TIMEOUT);
449 if (time_left == 0) {
450 dev_err(dev, "DMA rx timeout\n");
451 dmaengine_terminate_all(dma->chan_tx);
452 dmaengine_terminate_all(dma->chan_rx);
453 return -ETIMEDOUT;
454 }
455
456 return 0;
457 }
458
459 static void dspi_setup_accel(struct fsl_dspi *dspi);
460
dspi_dma_xfer(struct fsl_dspi * dspi)461 static int dspi_dma_xfer(struct fsl_dspi *dspi)
462 {
463 struct spi_message *message = dspi->cur_msg;
464 struct device *dev = &dspi->pdev->dev;
465 int ret = 0;
466
467 /*
468 * dspi->len gets decremented by dspi_pop_tx_pushr in
469 * dspi_next_xfer_dma_submit
470 */
471 while (dspi->len) {
472 /* Figure out operational bits-per-word for this chunk */
473 dspi_setup_accel(dspi);
474
475 dspi->words_in_flight = dspi->len / dspi->oper_word_size;
476 if (dspi->words_in_flight > dspi->devtype_data->fifo_size)
477 dspi->words_in_flight = dspi->devtype_data->fifo_size;
478
479 message->actual_length += dspi->words_in_flight *
480 dspi->oper_word_size;
481
482 ret = dspi_next_xfer_dma_submit(dspi);
483 if (ret) {
484 dev_err(dev, "DMA transfer failed\n");
485 break;
486 }
487 }
488
489 return ret;
490 }
491
dspi_request_dma(struct fsl_dspi * dspi,phys_addr_t phy_addr)492 static int dspi_request_dma(struct fsl_dspi *dspi, phys_addr_t phy_addr)
493 {
494 int dma_bufsize = dspi->devtype_data->fifo_size * 2;
495 struct device *dev = &dspi->pdev->dev;
496 struct dma_slave_config cfg;
497 struct fsl_dspi_dma *dma;
498 int ret;
499
500 dma = devm_kzalloc(dev, sizeof(*dma), GFP_KERNEL);
501 if (!dma)
502 return -ENOMEM;
503
504 dma->chan_rx = dma_request_chan(dev, "rx");
505 if (IS_ERR(dma->chan_rx)) {
506 return dev_err_probe(dev, PTR_ERR(dma->chan_rx),
507 "rx dma channel not available\n");
508 }
509
510 dma->chan_tx = dma_request_chan(dev, "tx");
511 if (IS_ERR(dma->chan_tx)) {
512 ret = PTR_ERR(dma->chan_tx);
513 dev_err_probe(dev, ret, "tx dma channel not available\n");
514 goto err_tx_channel;
515 }
516
517 dma->tx_dma_buf = dma_alloc_coherent(dma->chan_tx->device->dev,
518 dma_bufsize, &dma->tx_dma_phys,
519 GFP_KERNEL);
520 if (!dma->tx_dma_buf) {
521 ret = -ENOMEM;
522 goto err_tx_dma_buf;
523 }
524
525 dma->rx_dma_buf = dma_alloc_coherent(dma->chan_rx->device->dev,
526 dma_bufsize, &dma->rx_dma_phys,
527 GFP_KERNEL);
528 if (!dma->rx_dma_buf) {
529 ret = -ENOMEM;
530 goto err_rx_dma_buf;
531 }
532
533 memset(&cfg, 0, sizeof(cfg));
534 cfg.src_addr = phy_addr + SPI_POPR;
535 cfg.dst_addr = phy_addr + SPI_PUSHR;
536 cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
537 cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
538 cfg.src_maxburst = 1;
539 cfg.dst_maxburst = 1;
540
541 cfg.direction = DMA_DEV_TO_MEM;
542 ret = dmaengine_slave_config(dma->chan_rx, &cfg);
543 if (ret) {
544 dev_err(dev, "can't configure rx dma channel\n");
545 ret = -EINVAL;
546 goto err_slave_config;
547 }
548
549 cfg.direction = DMA_MEM_TO_DEV;
550 ret = dmaengine_slave_config(dma->chan_tx, &cfg);
551 if (ret) {
552 dev_err(dev, "can't configure tx dma channel\n");
553 ret = -EINVAL;
554 goto err_slave_config;
555 }
556
557 dspi->dma = dma;
558 init_completion(&dma->cmd_tx_complete);
559 init_completion(&dma->cmd_rx_complete);
560
561 return 0;
562
563 err_slave_config:
564 dma_free_coherent(dma->chan_rx->device->dev,
565 dma_bufsize, dma->rx_dma_buf, dma->rx_dma_phys);
566 err_rx_dma_buf:
567 dma_free_coherent(dma->chan_tx->device->dev,
568 dma_bufsize, dma->tx_dma_buf, dma->tx_dma_phys);
569 err_tx_dma_buf:
570 dma_release_channel(dma->chan_tx);
571 err_tx_channel:
572 dma_release_channel(dma->chan_rx);
573
574 devm_kfree(dev, dma);
575 dspi->dma = NULL;
576
577 return ret;
578 }
579
dspi_release_dma(struct fsl_dspi * dspi)580 static void dspi_release_dma(struct fsl_dspi *dspi)
581 {
582 int dma_bufsize = dspi->devtype_data->fifo_size * 2;
583 struct fsl_dspi_dma *dma = dspi->dma;
584
585 if (!dma)
586 return;
587
588 if (dma->chan_tx) {
589 dma_free_coherent(dma->chan_tx->device->dev, dma_bufsize,
590 dma->tx_dma_buf, dma->tx_dma_phys);
591 dma_release_channel(dma->chan_tx);
592 }
593
594 if (dma->chan_rx) {
595 dma_free_coherent(dma->chan_rx->device->dev, dma_bufsize,
596 dma->rx_dma_buf, dma->rx_dma_phys);
597 dma_release_channel(dma->chan_rx);
598 }
599 }
600
hz_to_spi_baud(char * pbr,char * br,int speed_hz,unsigned long clkrate)601 static void hz_to_spi_baud(char *pbr, char *br, int speed_hz,
602 unsigned long clkrate)
603 {
604 /* Valid baud rate pre-scaler values */
605 int pbr_tbl[4] = {2, 3, 5, 7};
606 int brs[16] = { 2, 4, 6, 8,
607 16, 32, 64, 128,
608 256, 512, 1024, 2048,
609 4096, 8192, 16384, 32768 };
610 int scale_needed, scale, minscale = INT_MAX;
611 int i, j;
612
613 scale_needed = clkrate / speed_hz;
614 if (clkrate % speed_hz)
615 scale_needed++;
616
617 for (i = 0; i < ARRAY_SIZE(brs); i++)
618 for (j = 0; j < ARRAY_SIZE(pbr_tbl); j++) {
619 scale = brs[i] * pbr_tbl[j];
620 if (scale >= scale_needed) {
621 if (scale < minscale) {
622 minscale = scale;
623 *br = i;
624 *pbr = j;
625 }
626 break;
627 }
628 }
629
630 if (minscale == INT_MAX) {
631 pr_warn("Can not find valid baud rate,speed_hz is %d,clkrate is %ld, we use the max prescaler value.\n",
632 speed_hz, clkrate);
633 *pbr = ARRAY_SIZE(pbr_tbl) - 1;
634 *br = ARRAY_SIZE(brs) - 1;
635 }
636 }
637
ns_delay_scale(char * psc,char * sc,int delay_ns,unsigned long clkrate)638 static void ns_delay_scale(char *psc, char *sc, int delay_ns,
639 unsigned long clkrate)
640 {
641 int scale_needed, scale, minscale = INT_MAX;
642 int pscale_tbl[4] = {1, 3, 5, 7};
643 u32 remainder;
644 int i, j;
645
646 scale_needed = div_u64_rem((u64)delay_ns * clkrate, NSEC_PER_SEC,
647 &remainder);
648 if (remainder)
649 scale_needed++;
650
651 for (i = 0; i < ARRAY_SIZE(pscale_tbl); i++)
652 for (j = 0; j <= SPI_CTAR_SCALE_BITS; j++) {
653 scale = pscale_tbl[i] * (2 << j);
654 if (scale >= scale_needed) {
655 if (scale < minscale) {
656 minscale = scale;
657 *psc = i;
658 *sc = j;
659 }
660 break;
661 }
662 }
663
664 if (minscale == INT_MAX) {
665 pr_warn("Cannot find correct scale values for %dns delay at clkrate %ld, using max prescaler value",
666 delay_ns, clkrate);
667 *psc = ARRAY_SIZE(pscale_tbl) - 1;
668 *sc = SPI_CTAR_SCALE_BITS;
669 }
670 }
671
dspi_pushr_cmd_write(struct fsl_dspi * dspi,u16 cmd)672 static void dspi_pushr_cmd_write(struct fsl_dspi *dspi, u16 cmd)
673 {
674 /*
675 * The only time when the PCS doesn't need continuation after this word
676 * is when it's last. We need to look ahead, because we actually call
677 * dspi_pop_tx (the function that decrements dspi->len) _after_
678 * dspi_pushr_cmd_write with XSPI mode. As for how much in advance? One
679 * word is enough. If there's more to transmit than that,
680 * dspi_xspi_write will know to split the FIFO writes in 2, and
681 * generate a new PUSHR command with the final word that will have PCS
682 * deasserted (not continued) here.
683 */
684 if (dspi->len > dspi->oper_word_size)
685 cmd |= SPI_PUSHR_CMD_CONT;
686 regmap_write(dspi->regmap_pushr, dspi->pushr_cmd, cmd);
687 }
688
dspi_pushr_txdata_write(struct fsl_dspi * dspi,u16 txdata)689 static void dspi_pushr_txdata_write(struct fsl_dspi *dspi, u16 txdata)
690 {
691 regmap_write(dspi->regmap_pushr, dspi->pushr_tx, txdata);
692 }
693
dspi_xspi_fifo_write(struct fsl_dspi * dspi,int num_words)694 static void dspi_xspi_fifo_write(struct fsl_dspi *dspi, int num_words)
695 {
696 int num_bytes = num_words * dspi->oper_word_size;
697 u16 tx_cmd = dspi->tx_cmd;
698
699 /*
700 * If the PCS needs to de-assert (i.e. we're at the end of the buffer
701 * and cs_change does not want the PCS to stay on), then we need a new
702 * PUSHR command, since this one (for the body of the buffer)
703 * necessarily has the CONT bit set.
704 * So send one word less during this go, to force a split and a command
705 * with a single word next time, when CONT will be unset.
706 */
707 if (!(dspi->tx_cmd & SPI_PUSHR_CMD_CONT) && num_bytes == dspi->len)
708 tx_cmd |= SPI_PUSHR_CMD_EOQ;
709
710 /* Update CTARE */
711 regmap_write(dspi->regmap, SPI_CTARE(0),
712 SPI_FRAME_EBITS(dspi->oper_bits_per_word) |
713 SPI_CTARE_DTCP(num_words));
714
715 /*
716 * Write the CMD FIFO entry first, and then the two
717 * corresponding TX FIFO entries (or one...).
718 */
719 dspi_pushr_cmd_write(dspi, tx_cmd);
720
721 /* Fill TX FIFO with as many transfers as possible */
722 while (num_words--) {
723 u32 data = dspi_pop_tx(dspi);
724
725 dspi_pushr_txdata_write(dspi, data & 0xFFFF);
726 if (dspi->oper_bits_per_word > 16)
727 dspi_pushr_txdata_write(dspi, data >> 16);
728 }
729 }
730
dspi_popr_read(struct fsl_dspi * dspi)731 static u32 dspi_popr_read(struct fsl_dspi *dspi)
732 {
733 u32 rxdata = 0;
734
735 regmap_read(dspi->regmap, SPI_POPR, &rxdata);
736 return rxdata;
737 }
738
dspi_fifo_read(struct fsl_dspi * dspi)739 static void dspi_fifo_read(struct fsl_dspi *dspi)
740 {
741 int num_fifo_entries = dspi->words_in_flight;
742
743 /* Read one FIFO entry and push to rx buffer */
744 while (num_fifo_entries--)
745 dspi_push_rx(dspi, dspi_popr_read(dspi));
746 }
747
dspi_setup_accel(struct fsl_dspi * dspi)748 static void dspi_setup_accel(struct fsl_dspi *dspi)
749 {
750 struct spi_transfer *xfer = dspi->cur_transfer;
751 bool odd = !!(dspi->len & 1);
752
753 /* No accel for frames not multiple of 8 bits at the moment */
754 if (xfer->bits_per_word % 8)
755 goto no_accel;
756
757 if (!odd && dspi->len <= dspi->devtype_data->fifo_size * 2) {
758 dspi->oper_bits_per_word = 16;
759 } else if (odd && dspi->len <= dspi->devtype_data->fifo_size) {
760 dspi->oper_bits_per_word = 8;
761 } else {
762 /* Start off with maximum supported by hardware */
763 if (dspi->devtype_data->trans_mode == DSPI_XSPI_MODE)
764 dspi->oper_bits_per_word = 32;
765 else
766 dspi->oper_bits_per_word = 16;
767
768 /*
769 * And go down only if the buffer can't be sent with
770 * words this big
771 */
772 do {
773 if (dspi->len >= DIV_ROUND_UP(dspi->oper_bits_per_word, 8))
774 break;
775
776 dspi->oper_bits_per_word /= 2;
777 } while (dspi->oper_bits_per_word > 8);
778 }
779
780 if (xfer->bits_per_word == 8 && dspi->oper_bits_per_word == 32) {
781 dspi->dev_to_host = dspi_8on32_dev_to_host;
782 dspi->host_to_dev = dspi_8on32_host_to_dev;
783 } else if (xfer->bits_per_word == 8 && dspi->oper_bits_per_word == 16) {
784 dspi->dev_to_host = dspi_8on16_dev_to_host;
785 dspi->host_to_dev = dspi_8on16_host_to_dev;
786 } else if (xfer->bits_per_word == 16 && dspi->oper_bits_per_word == 32) {
787 dspi->dev_to_host = dspi_16on32_dev_to_host;
788 dspi->host_to_dev = dspi_16on32_host_to_dev;
789 } else {
790 no_accel:
791 dspi->dev_to_host = dspi_native_dev_to_host;
792 dspi->host_to_dev = dspi_native_host_to_dev;
793 dspi->oper_bits_per_word = xfer->bits_per_word;
794 }
795
796 dspi->oper_word_size = DIV_ROUND_UP(dspi->oper_bits_per_word, 8);
797
798 /*
799 * Update CTAR here (code is common for XSPI and DMA modes).
800 * We will update CTARE in the portion specific to XSPI, when we
801 * also know the preload value (DTCP).
802 */
803 regmap_write(dspi->regmap, SPI_CTAR(0),
804 dspi->cur_chip->ctar_val |
805 SPI_FRAME_BITS(dspi->oper_bits_per_word));
806 }
807
dspi_fifo_write(struct fsl_dspi * dspi)808 static void dspi_fifo_write(struct fsl_dspi *dspi)
809 {
810 int num_fifo_entries = dspi->devtype_data->fifo_size;
811 struct spi_transfer *xfer = dspi->cur_transfer;
812 struct spi_message *msg = dspi->cur_msg;
813 int num_words, num_bytes;
814
815 dspi_setup_accel(dspi);
816
817 /* In XSPI mode each 32-bit word occupies 2 TX FIFO entries */
818 if (dspi->oper_word_size == 4)
819 num_fifo_entries /= 2;
820
821 /*
822 * Integer division intentionally trims off odd (or non-multiple of 4)
823 * numbers of bytes at the end of the buffer, which will be sent next
824 * time using a smaller oper_word_size.
825 */
826 num_words = dspi->len / dspi->oper_word_size;
827 if (num_words > num_fifo_entries)
828 num_words = num_fifo_entries;
829
830 /* Update total number of bytes that were transferred */
831 num_bytes = num_words * dspi->oper_word_size;
832 msg->actual_length += num_bytes;
833 dspi->progress += num_bytes / DIV_ROUND_UP(xfer->bits_per_word, 8);
834
835 /*
836 * Update shared variable for use in the next interrupt (both in
837 * dspi_fifo_read and in dspi_fifo_write).
838 */
839 dspi->words_in_flight = num_words;
840
841 spi_take_timestamp_pre(dspi->ctlr, xfer, dspi->progress, !dspi->irq);
842
843 dspi_xspi_fifo_write(dspi, num_words);
844 /*
845 * Everything after this point is in a potential race with the next
846 * interrupt, so we must never use dspi->words_in_flight again since it
847 * might already be modified by the next dspi_fifo_write.
848 */
849
850 spi_take_timestamp_post(dspi->ctlr, dspi->cur_transfer,
851 dspi->progress, !dspi->irq);
852 }
853
dspi_rxtx(struct fsl_dspi * dspi)854 static int dspi_rxtx(struct fsl_dspi *dspi)
855 {
856 dspi_fifo_read(dspi);
857
858 if (!dspi->len)
859 /* Success! */
860 return 0;
861
862 dspi_fifo_write(dspi);
863
864 return -EINPROGRESS;
865 }
866
dspi_poll(struct fsl_dspi * dspi)867 static int dspi_poll(struct fsl_dspi *dspi)
868 {
869 int tries = 1000;
870 u32 spi_sr;
871
872 do {
873 regmap_read(dspi->regmap, SPI_SR, &spi_sr);
874 regmap_write(dspi->regmap, SPI_SR, spi_sr);
875
876 if (spi_sr & SPI_SR_CMDTCF)
877 break;
878 } while (--tries);
879
880 if (!tries)
881 return -ETIMEDOUT;
882
883 return dspi_rxtx(dspi);
884 }
885
dspi_interrupt(int irq,void * dev_id)886 static irqreturn_t dspi_interrupt(int irq, void *dev_id)
887 {
888 struct fsl_dspi *dspi = (struct fsl_dspi *)dev_id;
889 u32 spi_sr;
890
891 regmap_read(dspi->regmap, SPI_SR, &spi_sr);
892 regmap_write(dspi->regmap, SPI_SR, spi_sr);
893
894 if (!(spi_sr & SPI_SR_CMDTCF))
895 return IRQ_NONE;
896
897 if (dspi_rxtx(dspi) == 0)
898 complete(&dspi->xfer_done);
899
900 return IRQ_HANDLED;
901 }
902
dspi_assert_cs(struct spi_device * spi,bool * cs)903 static void dspi_assert_cs(struct spi_device *spi, bool *cs)
904 {
905 if (!spi_get_csgpiod(spi, 0) || *cs)
906 return;
907
908 gpiod_set_value_cansleep(spi_get_csgpiod(spi, 0), true);
909 *cs = true;
910 }
911
dspi_deassert_cs(struct spi_device * spi,bool * cs)912 static void dspi_deassert_cs(struct spi_device *spi, bool *cs)
913 {
914 if (!spi_get_csgpiod(spi, 0) || !*cs)
915 return;
916
917 gpiod_set_value_cansleep(spi_get_csgpiod(spi, 0), false);
918 *cs = false;
919 }
920
dspi_transfer_one_message(struct spi_controller * ctlr,struct spi_message * message)921 static int dspi_transfer_one_message(struct spi_controller *ctlr,
922 struct spi_message *message)
923 {
924 struct fsl_dspi *dspi = spi_controller_get_devdata(ctlr);
925 struct spi_device *spi = message->spi;
926 struct spi_transfer *transfer;
927 bool cs = false;
928 int status = 0;
929
930 message->actual_length = 0;
931
932 list_for_each_entry(transfer, &message->transfers, transfer_list) {
933 dspi->cur_transfer = transfer;
934 dspi->cur_msg = message;
935 dspi->cur_chip = spi_get_ctldata(spi);
936
937 dspi_assert_cs(spi, &cs);
938
939 /* Prepare command word for CMD FIFO */
940 dspi->tx_cmd = SPI_PUSHR_CMD_CTAS(0);
941 if (!spi_get_csgpiod(spi, 0))
942 dspi->tx_cmd |= SPI_PUSHR_CMD_PCS(spi_get_chipselect(spi, 0));
943
944 if (list_is_last(&dspi->cur_transfer->transfer_list,
945 &dspi->cur_msg->transfers)) {
946 /* Leave PCS activated after last transfer when
947 * cs_change is set.
948 */
949 if (transfer->cs_change)
950 dspi->tx_cmd |= SPI_PUSHR_CMD_CONT;
951 } else {
952 /* Keep PCS active between transfers in same message
953 * when cs_change is not set, and de-activate PCS
954 * between transfers in the same message when
955 * cs_change is set.
956 */
957 if (!transfer->cs_change)
958 dspi->tx_cmd |= SPI_PUSHR_CMD_CONT;
959 }
960
961 dspi->tx = transfer->tx_buf;
962 dspi->rx = transfer->rx_buf;
963 dspi->len = transfer->len;
964 dspi->progress = 0;
965
966 regmap_update_bits(dspi->regmap, SPI_MCR,
967 SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF,
968 SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF);
969
970 spi_take_timestamp_pre(dspi->ctlr, dspi->cur_transfer,
971 dspi->progress, !dspi->irq);
972
973 if (dspi->devtype_data->trans_mode == DSPI_DMA_MODE) {
974 status = dspi_dma_xfer(dspi);
975 } else {
976 dspi_fifo_write(dspi);
977
978 if (dspi->irq) {
979 wait_for_completion(&dspi->xfer_done);
980 reinit_completion(&dspi->xfer_done);
981 } else {
982 do {
983 status = dspi_poll(dspi);
984 } while (status == -EINPROGRESS);
985 }
986 }
987 if (status)
988 break;
989
990 spi_transfer_delay_exec(transfer);
991
992 if (!(dspi->tx_cmd & SPI_PUSHR_CMD_CONT))
993 dspi_deassert_cs(spi, &cs);
994 }
995
996 message->status = status;
997 spi_finalize_current_message(ctlr);
998
999 return status;
1000 }
1001
dspi_setup(struct spi_device * spi)1002 static int dspi_setup(struct spi_device *spi)
1003 {
1004 struct fsl_dspi *dspi = spi_controller_get_devdata(spi->controller);
1005 u32 period_ns = DIV_ROUND_UP(NSEC_PER_SEC, spi->max_speed_hz);
1006 unsigned char br = 0, pbr = 0, pcssck = 0, cssck = 0;
1007 u32 quarter_period_ns = DIV_ROUND_UP(period_ns, 4);
1008 u32 cs_sck_delay = 0, sck_cs_delay = 0;
1009 struct fsl_dspi_platform_data *pdata;
1010 unsigned char pasc = 0, asc = 0;
1011 struct chip_data *chip;
1012 unsigned long clkrate;
1013 bool cs = true;
1014
1015 /* Only alloc on first setup */
1016 chip = spi_get_ctldata(spi);
1017 if (chip == NULL) {
1018 chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
1019 if (!chip)
1020 return -ENOMEM;
1021 }
1022
1023 pdata = dev_get_platdata(&dspi->pdev->dev);
1024
1025 if (!pdata) {
1026 of_property_read_u32(spi->dev.of_node, "fsl,spi-cs-sck-delay",
1027 &cs_sck_delay);
1028
1029 of_property_read_u32(spi->dev.of_node, "fsl,spi-sck-cs-delay",
1030 &sck_cs_delay);
1031 } else {
1032 cs_sck_delay = pdata->cs_sck_delay;
1033 sck_cs_delay = pdata->sck_cs_delay;
1034 }
1035
1036 /* Since tCSC and tASC apply to continuous transfers too, avoid SCK
1037 * glitches of half a cycle by never allowing tCSC + tASC to go below
1038 * half a SCK period.
1039 */
1040 if (cs_sck_delay < quarter_period_ns)
1041 cs_sck_delay = quarter_period_ns;
1042 if (sck_cs_delay < quarter_period_ns)
1043 sck_cs_delay = quarter_period_ns;
1044
1045 dev_dbg(&spi->dev,
1046 "DSPI controller timing params: CS-to-SCK delay %u ns, SCK-to-CS delay %u ns\n",
1047 cs_sck_delay, sck_cs_delay);
1048
1049 clkrate = clk_get_rate(dspi->clk);
1050 hz_to_spi_baud(&pbr, &br, spi->max_speed_hz, clkrate);
1051
1052 /* Set PCS to SCK delay scale values */
1053 ns_delay_scale(&pcssck, &cssck, cs_sck_delay, clkrate);
1054
1055 /* Set After SCK delay scale values */
1056 ns_delay_scale(&pasc, &asc, sck_cs_delay, clkrate);
1057
1058 chip->ctar_val = 0;
1059 if (spi->mode & SPI_CPOL)
1060 chip->ctar_val |= SPI_CTAR_CPOL;
1061 if (spi->mode & SPI_CPHA)
1062 chip->ctar_val |= SPI_CTAR_CPHA;
1063
1064 if (!spi_controller_is_target(dspi->ctlr)) {
1065 chip->ctar_val |= SPI_CTAR_PCSSCK(pcssck) |
1066 SPI_CTAR_CSSCK(cssck) |
1067 SPI_CTAR_PASC(pasc) |
1068 SPI_CTAR_ASC(asc) |
1069 SPI_CTAR_PBR(pbr) |
1070 SPI_CTAR_BR(br);
1071
1072 if (spi->mode & SPI_LSB_FIRST)
1073 chip->ctar_val |= SPI_CTAR_LSBFE;
1074 }
1075
1076 gpiod_direction_output(spi_get_csgpiod(spi, 0), false);
1077 dspi_deassert_cs(spi, &cs);
1078
1079 spi_set_ctldata(spi, chip);
1080
1081 return 0;
1082 }
1083
dspi_cleanup(struct spi_device * spi)1084 static void dspi_cleanup(struct spi_device *spi)
1085 {
1086 struct chip_data *chip = spi_get_ctldata(spi);
1087
1088 dev_dbg(&spi->dev, "spi_device %u.%u cleanup\n",
1089 spi->controller->bus_num, spi_get_chipselect(spi, 0));
1090
1091 kfree(chip);
1092 }
1093
1094 static const struct of_device_id fsl_dspi_dt_ids[] = {
1095 {
1096 .compatible = "fsl,vf610-dspi",
1097 .data = &devtype_data[VF610],
1098 }, {
1099 .compatible = "fsl,ls1021a-v1.0-dspi",
1100 .data = &devtype_data[LS1021A],
1101 }, {
1102 .compatible = "fsl,ls1012a-dspi",
1103 .data = &devtype_data[LS1012A],
1104 }, {
1105 .compatible = "fsl,ls1028a-dspi",
1106 .data = &devtype_data[LS1028A],
1107 }, {
1108 .compatible = "fsl,ls1043a-dspi",
1109 .data = &devtype_data[LS1043A],
1110 }, {
1111 .compatible = "fsl,ls1046a-dspi",
1112 .data = &devtype_data[LS1046A],
1113 }, {
1114 .compatible = "fsl,ls2080a-dspi",
1115 .data = &devtype_data[LS2080A],
1116 }, {
1117 .compatible = "fsl,ls2085a-dspi",
1118 .data = &devtype_data[LS2085A],
1119 }, {
1120 .compatible = "fsl,lx2160a-dspi",
1121 .data = &devtype_data[LX2160A],
1122 },
1123 { /* sentinel */ }
1124 };
1125 MODULE_DEVICE_TABLE(of, fsl_dspi_dt_ids);
1126
1127 #ifdef CONFIG_PM_SLEEP
dspi_suspend(struct device * dev)1128 static int dspi_suspend(struct device *dev)
1129 {
1130 struct fsl_dspi *dspi = dev_get_drvdata(dev);
1131
1132 if (dspi->irq)
1133 disable_irq(dspi->irq);
1134 spi_controller_suspend(dspi->ctlr);
1135 clk_disable_unprepare(dspi->clk);
1136
1137 pinctrl_pm_select_sleep_state(dev);
1138
1139 return 0;
1140 }
1141
dspi_resume(struct device * dev)1142 static int dspi_resume(struct device *dev)
1143 {
1144 struct fsl_dspi *dspi = dev_get_drvdata(dev);
1145 int ret;
1146
1147 pinctrl_pm_select_default_state(dev);
1148
1149 ret = clk_prepare_enable(dspi->clk);
1150 if (ret)
1151 return ret;
1152 spi_controller_resume(dspi->ctlr);
1153 if (dspi->irq)
1154 enable_irq(dspi->irq);
1155
1156 return 0;
1157 }
1158 #endif /* CONFIG_PM_SLEEP */
1159
1160 static SIMPLE_DEV_PM_OPS(dspi_pm, dspi_suspend, dspi_resume);
1161
1162 static const struct regmap_range dspi_volatile_ranges[] = {
1163 regmap_reg_range(SPI_MCR, SPI_TCR),
1164 regmap_reg_range(SPI_SR, SPI_SR),
1165 regmap_reg_range(SPI_PUSHR, SPI_RXFR3),
1166 };
1167
1168 static const struct regmap_access_table dspi_volatile_table = {
1169 .yes_ranges = dspi_volatile_ranges,
1170 .n_yes_ranges = ARRAY_SIZE(dspi_volatile_ranges),
1171 };
1172
1173 static const struct regmap_config dspi_regmap_config = {
1174 .reg_bits = 32,
1175 .val_bits = 32,
1176 .reg_stride = 4,
1177 .max_register = 0x88,
1178 .volatile_table = &dspi_volatile_table,
1179 };
1180
1181 static const struct regmap_range dspi_xspi_volatile_ranges[] = {
1182 regmap_reg_range(SPI_MCR, SPI_TCR),
1183 regmap_reg_range(SPI_SR, SPI_SR),
1184 regmap_reg_range(SPI_PUSHR, SPI_RXFR3),
1185 regmap_reg_range(SPI_SREX, SPI_SREX),
1186 };
1187
1188 static const struct regmap_access_table dspi_xspi_volatile_table = {
1189 .yes_ranges = dspi_xspi_volatile_ranges,
1190 .n_yes_ranges = ARRAY_SIZE(dspi_xspi_volatile_ranges),
1191 };
1192
1193 static const struct regmap_config dspi_xspi_regmap_config[] = {
1194 {
1195 .reg_bits = 32,
1196 .val_bits = 32,
1197 .reg_stride = 4,
1198 .max_register = 0x13c,
1199 .volatile_table = &dspi_xspi_volatile_table,
1200 },
1201 {
1202 .name = "pushr",
1203 .reg_bits = 16,
1204 .val_bits = 16,
1205 .reg_stride = 2,
1206 .max_register = 0x2,
1207 },
1208 };
1209
dspi_init(struct fsl_dspi * dspi)1210 static int dspi_init(struct fsl_dspi *dspi)
1211 {
1212 unsigned int mcr;
1213
1214 /* Set idle states for all chip select signals to high */
1215 mcr = SPI_MCR_PCSIS(GENMASK(dspi->ctlr->max_native_cs - 1, 0));
1216
1217 if (dspi->devtype_data->trans_mode == DSPI_XSPI_MODE)
1218 mcr |= SPI_MCR_XSPI;
1219 if (!spi_controller_is_target(dspi->ctlr))
1220 mcr |= SPI_MCR_HOST;
1221
1222 regmap_write(dspi->regmap, SPI_MCR, mcr);
1223 regmap_write(dspi->regmap, SPI_SR, SPI_SR_CLEAR);
1224
1225 switch (dspi->devtype_data->trans_mode) {
1226 case DSPI_XSPI_MODE:
1227 regmap_write(dspi->regmap, SPI_RSER, SPI_RSER_CMDTCFE);
1228 break;
1229 case DSPI_DMA_MODE:
1230 regmap_write(dspi->regmap, SPI_RSER,
1231 SPI_RSER_TFFFE | SPI_RSER_TFFFD |
1232 SPI_RSER_RFDFE | SPI_RSER_RFDFD);
1233 break;
1234 default:
1235 dev_err(&dspi->pdev->dev, "unsupported trans_mode %u\n",
1236 dspi->devtype_data->trans_mode);
1237 return -EINVAL;
1238 }
1239
1240 return 0;
1241 }
1242
dspi_target_abort(struct spi_controller * host)1243 static int dspi_target_abort(struct spi_controller *host)
1244 {
1245 struct fsl_dspi *dspi = spi_controller_get_devdata(host);
1246
1247 /*
1248 * Terminate all pending DMA transactions for the SPI working
1249 * in TARGET mode.
1250 */
1251 if (dspi->devtype_data->trans_mode == DSPI_DMA_MODE) {
1252 dmaengine_terminate_sync(dspi->dma->chan_rx);
1253 dmaengine_terminate_sync(dspi->dma->chan_tx);
1254 }
1255
1256 /* Clear the internal DSPI RX and TX FIFO buffers */
1257 regmap_update_bits(dspi->regmap, SPI_MCR,
1258 SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF,
1259 SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF);
1260
1261 return 0;
1262 }
1263
dspi_probe(struct platform_device * pdev)1264 static int dspi_probe(struct platform_device *pdev)
1265 {
1266 struct device_node *np = pdev->dev.of_node;
1267 const struct regmap_config *regmap_config;
1268 struct fsl_dspi_platform_data *pdata;
1269 struct spi_controller *ctlr;
1270 int ret, cs_num, bus_num = -1;
1271 struct fsl_dspi *dspi;
1272 struct resource *res;
1273 void __iomem *base;
1274 bool big_endian;
1275
1276 dspi = devm_kzalloc(&pdev->dev, sizeof(*dspi), GFP_KERNEL);
1277 if (!dspi)
1278 return -ENOMEM;
1279
1280 ctlr = spi_alloc_host(&pdev->dev, 0);
1281 if (!ctlr)
1282 return -ENOMEM;
1283
1284 spi_controller_set_devdata(ctlr, dspi);
1285 platform_set_drvdata(pdev, dspi);
1286
1287 dspi->pdev = pdev;
1288 dspi->ctlr = ctlr;
1289
1290 ctlr->setup = dspi_setup;
1291 ctlr->transfer_one_message = dspi_transfer_one_message;
1292 ctlr->dev.of_node = pdev->dev.of_node;
1293
1294 ctlr->cleanup = dspi_cleanup;
1295 ctlr->target_abort = dspi_target_abort;
1296 ctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;
1297 ctlr->use_gpio_descriptors = true;
1298
1299 pdata = dev_get_platdata(&pdev->dev);
1300 if (pdata) {
1301 ctlr->num_chipselect = ctlr->max_native_cs = pdata->cs_num;
1302 ctlr->bus_num = pdata->bus_num;
1303
1304 /* Only Coldfire uses platform data */
1305 dspi->devtype_data = &devtype_data[MCF5441X];
1306 big_endian = true;
1307 } else {
1308
1309 ret = of_property_read_u32(np, "spi-num-chipselects", &cs_num);
1310 if (ret < 0) {
1311 dev_err(&pdev->dev, "can't get spi-num-chipselects\n");
1312 goto out_ctlr_put;
1313 }
1314 ctlr->num_chipselect = ctlr->max_native_cs = cs_num;
1315
1316 of_property_read_u32(np, "bus-num", &bus_num);
1317 ctlr->bus_num = bus_num;
1318
1319 if (of_property_read_bool(np, "spi-slave"))
1320 ctlr->target = true;
1321
1322 dspi->devtype_data = of_device_get_match_data(&pdev->dev);
1323 if (!dspi->devtype_data) {
1324 dev_err(&pdev->dev, "can't get devtype_data\n");
1325 ret = -EFAULT;
1326 goto out_ctlr_put;
1327 }
1328
1329 big_endian = of_device_is_big_endian(np);
1330 }
1331 if (big_endian) {
1332 dspi->pushr_cmd = 0;
1333 dspi->pushr_tx = 2;
1334 } else {
1335 dspi->pushr_cmd = 2;
1336 dspi->pushr_tx = 0;
1337 }
1338
1339 if (dspi->devtype_data->trans_mode == DSPI_XSPI_MODE)
1340 ctlr->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1341 else
1342 ctlr->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16);
1343
1344 base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
1345 if (IS_ERR(base)) {
1346 ret = PTR_ERR(base);
1347 goto out_ctlr_put;
1348 }
1349
1350 if (dspi->devtype_data->trans_mode == DSPI_XSPI_MODE)
1351 regmap_config = &dspi_xspi_regmap_config[0];
1352 else
1353 regmap_config = &dspi_regmap_config;
1354 dspi->regmap = devm_regmap_init_mmio(&pdev->dev, base, regmap_config);
1355 if (IS_ERR(dspi->regmap)) {
1356 dev_err(&pdev->dev, "failed to init regmap: %ld\n",
1357 PTR_ERR(dspi->regmap));
1358 ret = PTR_ERR(dspi->regmap);
1359 goto out_ctlr_put;
1360 }
1361
1362 if (dspi->devtype_data->trans_mode == DSPI_XSPI_MODE) {
1363 dspi->regmap_pushr = devm_regmap_init_mmio(
1364 &pdev->dev, base + SPI_PUSHR,
1365 &dspi_xspi_regmap_config[1]);
1366 if (IS_ERR(dspi->regmap_pushr)) {
1367 dev_err(&pdev->dev,
1368 "failed to init pushr regmap: %ld\n",
1369 PTR_ERR(dspi->regmap_pushr));
1370 ret = PTR_ERR(dspi->regmap_pushr);
1371 goto out_ctlr_put;
1372 }
1373 }
1374
1375 dspi->clk = devm_clk_get(&pdev->dev, "dspi");
1376 if (IS_ERR(dspi->clk)) {
1377 ret = PTR_ERR(dspi->clk);
1378 dev_err(&pdev->dev, "unable to get clock\n");
1379 goto out_ctlr_put;
1380 }
1381 ret = clk_prepare_enable(dspi->clk);
1382 if (ret)
1383 goto out_ctlr_put;
1384
1385 ret = dspi_init(dspi);
1386 if (ret)
1387 goto out_clk_put;
1388
1389 dspi->irq = platform_get_irq(pdev, 0);
1390 if (dspi->irq <= 0) {
1391 dev_info(&pdev->dev,
1392 "can't get platform irq, using poll mode\n");
1393 dspi->irq = 0;
1394 goto poll_mode;
1395 }
1396
1397 init_completion(&dspi->xfer_done);
1398
1399 ret = request_threaded_irq(dspi->irq, dspi_interrupt, NULL,
1400 IRQF_SHARED, pdev->name, dspi);
1401 if (ret < 0) {
1402 dev_err(&pdev->dev, "Unable to attach DSPI interrupt\n");
1403 goto out_clk_put;
1404 }
1405
1406 poll_mode:
1407
1408 if (dspi->devtype_data->trans_mode == DSPI_DMA_MODE) {
1409 ret = dspi_request_dma(dspi, res->start);
1410 if (ret < 0) {
1411 dev_err(&pdev->dev, "can't get dma channels\n");
1412 goto out_free_irq;
1413 }
1414 }
1415
1416 ctlr->max_speed_hz =
1417 clk_get_rate(dspi->clk) / dspi->devtype_data->max_clock_factor;
1418
1419 if (dspi->devtype_data->trans_mode != DSPI_DMA_MODE)
1420 ctlr->ptp_sts_supported = true;
1421
1422 ret = spi_register_controller(ctlr);
1423 if (ret != 0) {
1424 dev_err(&pdev->dev, "Problem registering DSPI ctlr\n");
1425 goto out_release_dma;
1426 }
1427
1428 return ret;
1429
1430 out_release_dma:
1431 dspi_release_dma(dspi);
1432 out_free_irq:
1433 if (dspi->irq)
1434 free_irq(dspi->irq, dspi);
1435 out_clk_put:
1436 clk_disable_unprepare(dspi->clk);
1437 out_ctlr_put:
1438 spi_controller_put(ctlr);
1439
1440 return ret;
1441 }
1442
dspi_remove(struct platform_device * pdev)1443 static void dspi_remove(struct platform_device *pdev)
1444 {
1445 struct fsl_dspi *dspi = platform_get_drvdata(pdev);
1446
1447 /* Disconnect from the SPI framework */
1448 spi_unregister_controller(dspi->ctlr);
1449
1450 /* Disable RX and TX */
1451 regmap_update_bits(dspi->regmap, SPI_MCR,
1452 SPI_MCR_DIS_TXF | SPI_MCR_DIS_RXF,
1453 SPI_MCR_DIS_TXF | SPI_MCR_DIS_RXF);
1454
1455 /* Stop Running */
1456 regmap_update_bits(dspi->regmap, SPI_MCR, SPI_MCR_HALT, SPI_MCR_HALT);
1457
1458 dspi_release_dma(dspi);
1459 if (dspi->irq)
1460 free_irq(dspi->irq, dspi);
1461 clk_disable_unprepare(dspi->clk);
1462 }
1463
dspi_shutdown(struct platform_device * pdev)1464 static void dspi_shutdown(struct platform_device *pdev)
1465 {
1466 dspi_remove(pdev);
1467 }
1468
1469 static struct platform_driver fsl_dspi_driver = {
1470 .driver.name = DRIVER_NAME,
1471 .driver.of_match_table = fsl_dspi_dt_ids,
1472 .driver.owner = THIS_MODULE,
1473 .driver.pm = &dspi_pm,
1474 .probe = dspi_probe,
1475 .remove_new = dspi_remove,
1476 .shutdown = dspi_shutdown,
1477 };
1478 module_platform_driver(fsl_dspi_driver);
1479
1480 MODULE_DESCRIPTION("Freescale DSPI Controller Driver");
1481 MODULE_LICENSE("GPL");
1482 MODULE_ALIAS("platform:" DRIVER_NAME);
1483