xref: /linux/drivers/spi/spi-fsl-dspi.c (revision 07fdad3a93756b872da7b53647715c48d0f4a2d0)
1 // SPDX-License-Identifier: GPL-2.0+
2 //
3 // Copyright 2013 Freescale Semiconductor, Inc.
4 // Copyright 2020-2025 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_MTFE			BIT(26)
28 #define SPI_MCR_PCSIS(x)		((x) << 16)
29 #define SPI_MCR_CLR_TXF			BIT(11)
30 #define SPI_MCR_CLR_RXF			BIT(10)
31 #define SPI_MCR_XSPI			BIT(3)
32 #define SPI_MCR_DIS_TXF			BIT(13)
33 #define SPI_MCR_DIS_RXF			BIT(12)
34 #define SPI_MCR_HALT			BIT(0)
35 
36 #define SPI_TCR				0x08
37 #define SPI_TCR_GET_TCNT(x)		(((x) & GENMASK(31, 16)) >> 16)
38 
39 #define SPI_CTAR(x)			(0x0c + (((x) & GENMASK(2, 0)) * 4))
40 #define SPI_CTAR_FMSZ(x)		(((x) << 27) & GENMASK(30, 27))
41 #define SPI_CTAR_DBR			BIT(31)
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_TFUF			BIT(27)
60 #define SPI_SR_TFFF			BIT(25)
61 #define SPI_SR_CMDTCF			BIT(23)
62 #define SPI_SR_SPEF			BIT(21)
63 #define SPI_SR_RFOF			BIT(19)
64 #define SPI_SR_TFIWF			BIT(18)
65 #define SPI_SR_RFDF			BIT(17)
66 #define SPI_SR_CMDFFF			BIT(16)
67 #define SPI_SR_TXRXS			BIT(30)
68 #define SPI_SR_CLEAR			(SPI_SR_TCFQF | \
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_CMDTCFE		BIT(23)
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_TXFR4			0x4C
99 #define SPI_RXFR0			0x7c
100 #define SPI_RXFR1			0x80
101 #define SPI_RXFR2			0x84
102 #define SPI_RXFR3			0x88
103 #define SPI_RXFR4			0x8C
104 
105 #define SPI_CTARE(x)			(0x11c + (((x) & GENMASK(2, 0)) * 4))
106 #define SPI_CTARE_FMSZE(x)		(((x) & 0x1) << 16)
107 #define SPI_CTARE_DTCP(x)		((x) & 0x7ff)
108 
109 #define SPI_SREX			0x13c
110 
111 #define SPI_FRAME_BITS(bits)		SPI_CTAR_FMSZ((bits) - 1)
112 #define SPI_FRAME_EBITS(bits)		SPI_CTARE_FMSZE(((bits) - 1) >> 4)
113 
114 #define DMA_COMPLETION_TIMEOUT		msecs_to_jiffies(3000)
115 
116 #define SPI_25MHZ			25000000
117 
118 struct chip_data {
119 	u32			ctar_val;
120 };
121 
122 enum dspi_trans_mode {
123 	DSPI_XSPI_MODE,
124 	DSPI_DMA_MODE,
125 };
126 
127 struct fsl_dspi_devtype_data {
128 	enum dspi_trans_mode	trans_mode;
129 	u8			max_clock_factor;
130 	int			fifo_size;
131 	const struct regmap_config *regmap;
132 };
133 
134 enum {
135 	LS1021A,
136 	LS1012A,
137 	LS1028A,
138 	LS1043A,
139 	LS1046A,
140 	LS2080A,
141 	LS2085A,
142 	LX2160A,
143 	MCF5441X,
144 	VF610,
145 	S32G,
146 	S32G_TARGET,
147 };
148 
149 static const struct regmap_range dspi_yes_ranges[] = {
150 	regmap_reg_range(SPI_MCR, SPI_MCR),
151 	regmap_reg_range(SPI_TCR, SPI_CTAR(3)),
152 	regmap_reg_range(SPI_SR, SPI_TXFR3),
153 	regmap_reg_range(SPI_RXFR0, SPI_RXFR3),
154 	regmap_reg_range(SPI_CTARE(0), SPI_CTARE(3)),
155 	regmap_reg_range(SPI_SREX, SPI_SREX),
156 };
157 
158 static const struct regmap_range s32g_dspi_yes_ranges[] = {
159 	regmap_reg_range(SPI_MCR, SPI_MCR),
160 	regmap_reg_range(SPI_TCR, SPI_CTAR(5)),
161 	regmap_reg_range(SPI_SR, SPI_TXFR4),
162 	regmap_reg_range(SPI_RXFR0, SPI_RXFR4),
163 	regmap_reg_range(SPI_CTARE(0), SPI_CTARE(5)),
164 	regmap_reg_range(SPI_SREX, SPI_SREX),
165 };
166 
167 static const struct regmap_access_table dspi_access_table = {
168 	.yes_ranges	= dspi_yes_ranges,
169 	.n_yes_ranges	= ARRAY_SIZE(dspi_yes_ranges),
170 };
171 
172 static const struct regmap_access_table s32g_dspi_access_table = {
173 	.yes_ranges	= s32g_dspi_yes_ranges,
174 	.n_yes_ranges	= ARRAY_SIZE(s32g_dspi_yes_ranges),
175 };
176 
177 static const struct regmap_range dspi_volatile_ranges[] = {
178 	regmap_reg_range(SPI_MCR, SPI_TCR),
179 	regmap_reg_range(SPI_SR, SPI_SR),
180 	regmap_reg_range(SPI_PUSHR, SPI_RXFR4),
181 	regmap_reg_range(SPI_SREX, SPI_SREX),
182 };
183 
184 static const struct regmap_access_table dspi_volatile_table = {
185 	.yes_ranges	= dspi_volatile_ranges,
186 	.n_yes_ranges	= ARRAY_SIZE(dspi_volatile_ranges),
187 };
188 
189 enum {
190 	DSPI_REGMAP,
191 	S32G_DSPI_REGMAP,
192 	DSPI_XSPI_REGMAP,
193 	S32G_DSPI_XSPI_REGMAP,
194 	DSPI_PUSHR,
195 };
196 
197 static const struct regmap_config dspi_regmap_config[] = {
198 	[DSPI_REGMAP] = {
199 		.reg_bits	= 32,
200 		.val_bits	= 32,
201 		.reg_stride	= 4,
202 		.max_register	= SPI_RXFR3,
203 		.volatile_table	= &dspi_volatile_table,
204 		.rd_table	= &dspi_access_table,
205 		.wr_table	= &dspi_access_table,
206 	},
207 	[S32G_DSPI_REGMAP] = {
208 		.reg_bits	= 32,
209 		.val_bits	= 32,
210 		.reg_stride	= 4,
211 		.max_register	= SPI_RXFR4,
212 		.volatile_table	= &dspi_volatile_table,
213 		.wr_table	= &s32g_dspi_access_table,
214 		.rd_table	= &s32g_dspi_access_table,
215 	},
216 	[DSPI_XSPI_REGMAP] = {
217 		.reg_bits	= 32,
218 		.val_bits	= 32,
219 		.reg_stride	= 4,
220 		.max_register	= SPI_SREX,
221 		.volatile_table	= &dspi_volatile_table,
222 		.rd_table	= &dspi_access_table,
223 		.wr_table	= &dspi_access_table,
224 	},
225 	[S32G_DSPI_XSPI_REGMAP] = {
226 		.reg_bits	= 32,
227 		.val_bits	= 32,
228 		.reg_stride	= 4,
229 		.max_register	= SPI_SREX,
230 		.volatile_table	= &dspi_volatile_table,
231 		.wr_table	= &s32g_dspi_access_table,
232 		.rd_table	= &s32g_dspi_access_table,
233 	},
234 	[DSPI_PUSHR] = {
235 		.name		= "pushr",
236 		.reg_bits	= 16,
237 		.val_bits	= 16,
238 		.reg_stride	= 2,
239 		.max_register	= 0x2,
240 	},
241 };
242 
243 static const struct fsl_dspi_devtype_data devtype_data[] = {
244 	[VF610] = {
245 		.trans_mode		= DSPI_DMA_MODE,
246 		.max_clock_factor	= 2,
247 		.fifo_size		= 4,
248 		.regmap			= &dspi_regmap_config[DSPI_REGMAP],
249 	},
250 	[LS1021A] = {
251 		/* Has A-011218 DMA erratum */
252 		.trans_mode		= DSPI_XSPI_MODE,
253 		.max_clock_factor	= 8,
254 		.fifo_size		= 4,
255 		.regmap			= &dspi_regmap_config[DSPI_XSPI_REGMAP],
256 	},
257 	[LS1012A] = {
258 		/* Has A-011218 DMA erratum */
259 		.trans_mode		= DSPI_XSPI_MODE,
260 		.max_clock_factor	= 8,
261 		.fifo_size		= 16,
262 		.regmap			= &dspi_regmap_config[DSPI_XSPI_REGMAP],
263 	},
264 	[LS1028A] = {
265 		.trans_mode		= DSPI_XSPI_MODE,
266 		.max_clock_factor	= 8,
267 		.fifo_size		= 4,
268 		.regmap			= &dspi_regmap_config[DSPI_XSPI_REGMAP],
269 	},
270 	[LS1043A] = {
271 		/* Has A-011218 DMA erratum */
272 		.trans_mode		= DSPI_XSPI_MODE,
273 		.max_clock_factor	= 8,
274 		.fifo_size		= 16,
275 		.regmap			= &dspi_regmap_config[DSPI_XSPI_REGMAP],
276 	},
277 	[LS1046A] = {
278 		/* Has A-011218 DMA erratum */
279 		.trans_mode		= DSPI_XSPI_MODE,
280 		.max_clock_factor	= 8,
281 		.fifo_size		= 16,
282 		.regmap			= &dspi_regmap_config[DSPI_XSPI_REGMAP],
283 	},
284 	[LS2080A] = {
285 		.trans_mode		= DSPI_XSPI_MODE,
286 		.max_clock_factor	= 8,
287 		.fifo_size		= 4,
288 		.regmap			= &dspi_regmap_config[DSPI_XSPI_REGMAP],
289 	},
290 	[LS2085A] = {
291 		.trans_mode		= DSPI_XSPI_MODE,
292 		.max_clock_factor	= 8,
293 		.fifo_size		= 4,
294 		.regmap			= &dspi_regmap_config[DSPI_XSPI_REGMAP],
295 	},
296 	[LX2160A] = {
297 		.trans_mode		= DSPI_XSPI_MODE,
298 		.max_clock_factor	= 8,
299 		.fifo_size		= 4,
300 		.regmap			= &dspi_regmap_config[DSPI_XSPI_REGMAP],
301 	},
302 	[MCF5441X] = {
303 		.trans_mode		= DSPI_DMA_MODE,
304 		.max_clock_factor	= 8,
305 		.fifo_size		= 16,
306 		.regmap			= &dspi_regmap_config[DSPI_REGMAP],
307 	},
308 	[S32G] = {
309 		.trans_mode	  = DSPI_XSPI_MODE,
310 		.max_clock_factor = 1,
311 		.fifo_size	  = 5,
312 		.regmap		  = &dspi_regmap_config[S32G_DSPI_XSPI_REGMAP],
313 	},
314 	[S32G_TARGET] = {
315 		.trans_mode	  = DSPI_DMA_MODE,
316 		.max_clock_factor = 1,
317 		.fifo_size	  = 5,
318 		.regmap		  = &dspi_regmap_config[S32G_DSPI_REGMAP],
319 	},
320 };
321 
322 struct fsl_dspi_dma {
323 	u32					*tx_dma_buf;
324 	struct dma_chan				*chan_tx;
325 	dma_addr_t				tx_dma_phys;
326 	struct completion			cmd_tx_complete;
327 	struct dma_async_tx_descriptor		*tx_desc;
328 
329 	u32					*rx_dma_buf;
330 	struct dma_chan				*chan_rx;
331 	dma_addr_t				rx_dma_phys;
332 	struct completion			cmd_rx_complete;
333 	struct dma_async_tx_descriptor		*rx_desc;
334 
335 	size_t					bufsize;
336 };
337 
338 struct fsl_dspi {
339 	struct spi_controller			*ctlr;
340 	struct platform_device			*pdev;
341 
342 	struct regmap				*regmap;
343 	struct regmap				*regmap_pushr;
344 	int					irq;
345 	struct clk				*clk;
346 
347 	struct spi_transfer			*cur_transfer;
348 	struct spi_message			*cur_msg;
349 	struct chip_data			*cur_chip;
350 	size_t					progress;
351 	size_t					len;
352 	const void				*tx;
353 	void					*rx;
354 	u16					tx_cmd;
355 	bool					mtf_enabled;
356 	const struct fsl_dspi_devtype_data	*devtype_data;
357 
358 	struct completion			xfer_done;
359 
360 	struct fsl_dspi_dma			*dma;
361 
362 	int					oper_word_size;
363 	int					oper_bits_per_word;
364 
365 	int					words_in_flight;
366 
367 	/*
368 	 * Offsets for CMD and TXDATA within SPI_PUSHR when accessed
369 	 * individually (in XSPI mode)
370 	 */
371 	int					pushr_cmd;
372 	int					pushr_tx;
373 
374 	void (*host_to_dev)(struct fsl_dspi *dspi, u32 *txdata);
375 	void (*dev_to_host)(struct fsl_dspi *dspi, u32 rxdata);
376 };
377 
378 static void dspi_setup_accel(struct fsl_dspi *dspi);
379 
380 static bool is_s32g_dspi(struct fsl_dspi *data)
381 {
382 	return data->devtype_data == &devtype_data[S32G] ||
383 	       data->devtype_data == &devtype_data[S32G_TARGET];
384 }
385 
386 static void dspi_native_host_to_dev(struct fsl_dspi *dspi, u32 *txdata)
387 {
388 	switch (dspi->oper_word_size) {
389 	case 1:
390 		*txdata = *(u8 *)dspi->tx;
391 		break;
392 	case 2:
393 		*txdata = *(u16 *)dspi->tx;
394 		break;
395 	case 4:
396 		*txdata = *(u32 *)dspi->tx;
397 		break;
398 	}
399 	dspi->tx += dspi->oper_word_size;
400 }
401 
402 static void dspi_native_dev_to_host(struct fsl_dspi *dspi, u32 rxdata)
403 {
404 	switch (dspi->oper_word_size) {
405 	case 1:
406 		*(u8 *)dspi->rx = rxdata;
407 		break;
408 	case 2:
409 		*(u16 *)dspi->rx = rxdata;
410 		break;
411 	case 4:
412 		*(u32 *)dspi->rx = rxdata;
413 		break;
414 	}
415 	dspi->rx += dspi->oper_word_size;
416 }
417 
418 static void dspi_8on32_host_to_dev(struct fsl_dspi *dspi, u32 *txdata)
419 {
420 	*txdata = (__force u32)cpu_to_be32(*(u32 *)dspi->tx);
421 	dspi->tx += sizeof(u32);
422 }
423 
424 static void dspi_8on32_dev_to_host(struct fsl_dspi *dspi, u32 rxdata)
425 {
426 	*(u32 *)dspi->rx = be32_to_cpu((__force __be32)rxdata);
427 	dspi->rx += sizeof(u32);
428 }
429 
430 static void dspi_8on16_host_to_dev(struct fsl_dspi *dspi, u32 *txdata)
431 {
432 	*txdata = (__force u32)cpu_to_be16(*(u16 *)dspi->tx);
433 	dspi->tx += sizeof(u16);
434 }
435 
436 static void dspi_8on16_dev_to_host(struct fsl_dspi *dspi, u32 rxdata)
437 {
438 	*(u16 *)dspi->rx = be16_to_cpu((__force __be16)rxdata);
439 	dspi->rx += sizeof(u16);
440 }
441 
442 static void dspi_16on32_host_to_dev(struct fsl_dspi *dspi, u32 *txdata)
443 {
444 	u16 hi = *(u16 *)dspi->tx;
445 	u16 lo = *(u16 *)(dspi->tx + 2);
446 
447 	*txdata = (u32)hi << 16 | lo;
448 	dspi->tx += sizeof(u32);
449 }
450 
451 static void dspi_16on32_dev_to_host(struct fsl_dspi *dspi, u32 rxdata)
452 {
453 	u16 hi = rxdata & 0xffff;
454 	u16 lo = rxdata >> 16;
455 
456 	*(u16 *)dspi->rx = lo;
457 	*(u16 *)(dspi->rx + 2) = hi;
458 	dspi->rx += sizeof(u32);
459 }
460 
461 /*
462  * Pop one word from the TX buffer for pushing into the
463  * PUSHR register (TX FIFO)
464  */
465 static u32 dspi_pop_tx(struct fsl_dspi *dspi)
466 {
467 	u32 txdata = 0;
468 
469 	if (dspi->tx)
470 		dspi->host_to_dev(dspi, &txdata);
471 	dspi->len -= dspi->oper_word_size;
472 	return txdata;
473 }
474 
475 /* Push one word to the RX buffer from the POPR register (RX FIFO) */
476 static void dspi_push_rx(struct fsl_dspi *dspi, u32 rxdata)
477 {
478 	if (!dspi->rx)
479 		return;
480 	dspi->dev_to_host(dspi, rxdata);
481 }
482 
483 static int dspi_fifo_error(struct fsl_dspi *dspi, u32 spi_sr)
484 {
485 	if (spi_sr & (SPI_SR_TFUF | SPI_SR_RFOF)) {
486 		dev_err_ratelimited(&dspi->pdev->dev, "FIFO errors:%s%s\n",
487 				    spi_sr & SPI_SR_TFUF ? " TX underflow," : "",
488 				    spi_sr & SPI_SR_RFOF ? " RX overflow," : "");
489 		return -EIO;
490 	}
491 	return 0;
492 }
493 
494 #if IS_ENABLED(CONFIG_DMA_ENGINE)
495 
496 /* Prepare one TX FIFO entry (txdata plus cmd) */
497 static u32 dspi_pop_tx_pushr(struct fsl_dspi *dspi)
498 {
499 	u16 cmd = dspi->tx_cmd, data = dspi_pop_tx(dspi);
500 
501 	if (spi_controller_is_target(dspi->ctlr))
502 		return data;
503 
504 	if (dspi->len > 0)
505 		cmd |= SPI_PUSHR_CMD_CONT;
506 	return cmd << 16 | data;
507 }
508 
509 static size_t dspi_dma_max_datawords(struct fsl_dspi *dspi)
510 {
511 	/*
512 	 * Transfers look like one of these, so we always use a full DMA word
513 	 * regardless of SPI word size:
514 	 *
515 	 * 31              16 15                   0
516 	 * -----------------------------------------
517 	 * |   CONTROL WORD  |     16-bit DATA     |
518 	 * -----------------------------------------
519 	 * or
520 	 * -----------------------------------------
521 	 * |   CONTROL WORD  | UNUSED | 8-bit DATA |
522 	 * -----------------------------------------
523 	 */
524 	return dspi->dma->bufsize / DMA_SLAVE_BUSWIDTH_4_BYTES;
525 }
526 
527 static size_t dspi_dma_transfer_size(struct fsl_dspi *dspi)
528 {
529 	return dspi->words_in_flight * DMA_SLAVE_BUSWIDTH_4_BYTES;
530 }
531 
532 static void dspi_tx_dma_callback(void *arg)
533 {
534 	struct fsl_dspi *dspi = arg;
535 	struct fsl_dspi_dma *dma = dspi->dma;
536 	struct device *dev = &dspi->pdev->dev;
537 
538 	dma_sync_single_for_cpu(dev, dma->tx_dma_phys,
539 				dspi_dma_transfer_size(dspi), DMA_TO_DEVICE);
540 	complete(&dma->cmd_tx_complete);
541 }
542 
543 static void dspi_rx_dma_callback(void *arg)
544 {
545 	struct fsl_dspi *dspi = arg;
546 	struct fsl_dspi_dma *dma = dspi->dma;
547 	struct device *dev = &dspi->pdev->dev;
548 	int i;
549 
550 	if (dspi->rx) {
551 		dma_sync_single_for_cpu(dev, dma->rx_dma_phys,
552 					dspi_dma_transfer_size(dspi),
553 					DMA_FROM_DEVICE);
554 		for (i = 0; i < dspi->words_in_flight; i++)
555 			dspi_push_rx(dspi, dspi->dma->rx_dma_buf[i]);
556 	}
557 
558 	complete(&dma->cmd_rx_complete);
559 }
560 
561 static int dspi_next_xfer_dma_submit(struct fsl_dspi *dspi)
562 {
563 	size_t size = dspi_dma_transfer_size(dspi);
564 	struct device *dev = &dspi->pdev->dev;
565 	struct fsl_dspi_dma *dma = dspi->dma;
566 	int time_left;
567 	u32 spi_sr;
568 	int i;
569 
570 	for (i = 0; i < dspi->words_in_flight; i++)
571 		dspi->dma->tx_dma_buf[i] = dspi_pop_tx_pushr(dspi);
572 
573 	dma_sync_single_for_device(dev, dma->tx_dma_phys, size, DMA_TO_DEVICE);
574 	dma->tx_desc = dmaengine_prep_slave_single(dma->chan_tx,
575 						   dma->tx_dma_phys, size,
576 						   DMA_MEM_TO_DEV,
577 						   DMA_PREP_INTERRUPT |
578 						   DMA_CTRL_ACK);
579 	if (!dma->tx_desc) {
580 		dev_err(dev, "Not able to get desc for DMA xfer\n");
581 		return -EIO;
582 	}
583 
584 	dma->tx_desc->callback = dspi_tx_dma_callback;
585 	dma->tx_desc->callback_param = dspi;
586 	if (dma_submit_error(dmaengine_submit(dma->tx_desc))) {
587 		dev_err(dev, "DMA submit failed\n");
588 		return -EINVAL;
589 	}
590 
591 	dma_sync_single_for_device(dev, dma->rx_dma_phys, size,
592 				   DMA_FROM_DEVICE);
593 	dma->rx_desc = dmaengine_prep_slave_single(dma->chan_rx,
594 						   dma->rx_dma_phys, size,
595 						   DMA_DEV_TO_MEM,
596 						   DMA_PREP_INTERRUPT |
597 						   DMA_CTRL_ACK);
598 	if (!dma->rx_desc) {
599 		dev_err(dev, "Not able to get desc for DMA xfer\n");
600 		return -EIO;
601 	}
602 
603 	dma->rx_desc->callback = dspi_rx_dma_callback;
604 	dma->rx_desc->callback_param = dspi;
605 	if (dma_submit_error(dmaengine_submit(dma->rx_desc))) {
606 		dev_err(dev, "DMA submit failed\n");
607 		return -EINVAL;
608 	}
609 
610 	reinit_completion(&dspi->dma->cmd_rx_complete);
611 	reinit_completion(&dspi->dma->cmd_tx_complete);
612 
613 	dma_async_issue_pending(dma->chan_rx);
614 	dma_async_issue_pending(dma->chan_tx);
615 
616 	if (spi_controller_is_target(dspi->ctlr)) {
617 		wait_for_completion_interruptible(&dspi->dma->cmd_rx_complete);
618 		regmap_read(dspi->regmap, SPI_SR, &spi_sr);
619 		return dspi_fifo_error(dspi, spi_sr);
620 	}
621 
622 	time_left = wait_for_completion_timeout(&dspi->dma->cmd_tx_complete,
623 						DMA_COMPLETION_TIMEOUT);
624 	if (time_left == 0) {
625 		dev_err(dev, "DMA tx timeout\n");
626 		dmaengine_terminate_all(dma->chan_tx);
627 		dmaengine_terminate_all(dma->chan_rx);
628 		return -ETIMEDOUT;
629 	}
630 
631 	time_left = wait_for_completion_timeout(&dspi->dma->cmd_rx_complete,
632 						DMA_COMPLETION_TIMEOUT);
633 	if (time_left == 0) {
634 		dev_err(dev, "DMA rx timeout\n");
635 		dmaengine_terminate_all(dma->chan_tx);
636 		dmaengine_terminate_all(dma->chan_rx);
637 		return -ETIMEDOUT;
638 	}
639 
640 	return 0;
641 }
642 
643 static void dspi_dma_xfer(struct fsl_dspi *dspi)
644 {
645 	struct spi_message *message = dspi->cur_msg;
646 	struct device *dev = &dspi->pdev->dev;
647 
648 	/*
649 	 * dspi->len gets decremented by dspi_pop_tx_pushr in
650 	 * dspi_next_xfer_dma_submit
651 	 */
652 	while (dspi->len) {
653 		/* Figure out operational bits-per-word for this chunk */
654 		dspi_setup_accel(dspi);
655 
656 		dspi->words_in_flight = min(dspi->len / dspi->oper_word_size,
657 					    dspi_dma_max_datawords(dspi));
658 
659 		message->actual_length += dspi->words_in_flight *
660 					  dspi->oper_word_size;
661 
662 		message->status = dspi_next_xfer_dma_submit(dspi);
663 		if (message->status) {
664 			dev_err(dev, "DMA transfer failed\n");
665 			break;
666 		}
667 	}
668 }
669 
670 static int dspi_request_dma(struct fsl_dspi *dspi, phys_addr_t phy_addr)
671 {
672 	struct device *dev = &dspi->pdev->dev;
673 	struct dma_slave_config cfg;
674 	struct fsl_dspi_dma *dma;
675 	int ret;
676 
677 	dma = devm_kzalloc(dev, sizeof(*dma), GFP_KERNEL);
678 	if (!dma)
679 		return -ENOMEM;
680 
681 	dma->chan_rx = dma_request_chan(dev, "rx");
682 	if (IS_ERR(dma->chan_rx))
683 		return dev_err_probe(dev, PTR_ERR(dma->chan_rx), "rx dma channel not available\n");
684 
685 	dma->chan_tx = dma_request_chan(dev, "tx");
686 	if (IS_ERR(dma->chan_tx)) {
687 		ret = dev_err_probe(dev, PTR_ERR(dma->chan_tx), "tx dma channel not available\n");
688 		goto err_tx_channel;
689 	}
690 
691 	if (spi_controller_is_target(dspi->ctlr)) {
692 		/*
693 		 * In target mode we have to be ready to receive the maximum
694 		 * that can possibly be transferred at once by EDMA without any
695 		 * FIFO underflows.
696 		 */
697 		dma->bufsize = min(dma_get_max_seg_size(dma->chan_rx->device->dev),
698 				   dma_get_max_seg_size(dma->chan_tx->device->dev)) *
699 			       DMA_SLAVE_BUSWIDTH_4_BYTES;
700 	} else {
701 		dma->bufsize = PAGE_SIZE;
702 	}
703 
704 	dma->tx_dma_buf = dma_alloc_noncoherent(dma->chan_tx->device->dev,
705 						dma->bufsize, &dma->tx_dma_phys,
706 						DMA_TO_DEVICE, GFP_KERNEL);
707 	if (!dma->tx_dma_buf) {
708 		ret = -ENOMEM;
709 		goto err_tx_dma_buf;
710 	}
711 
712 	dma->rx_dma_buf = dma_alloc_noncoherent(dma->chan_rx->device->dev,
713 						dma->bufsize, &dma->rx_dma_phys,
714 						DMA_FROM_DEVICE, GFP_KERNEL);
715 	if (!dma->rx_dma_buf) {
716 		ret = -ENOMEM;
717 		goto err_rx_dma_buf;
718 	}
719 
720 	memset(&cfg, 0, sizeof(cfg));
721 	cfg.src_addr = phy_addr + SPI_POPR;
722 	cfg.dst_addr = phy_addr + SPI_PUSHR;
723 	cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
724 	cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
725 	cfg.src_maxburst = 1;
726 	cfg.dst_maxburst = 1;
727 
728 	cfg.direction = DMA_DEV_TO_MEM;
729 	ret = dmaengine_slave_config(dma->chan_rx, &cfg);
730 	if (ret) {
731 		dev_err_probe(dev, ret, "can't configure rx dma channel\n");
732 		goto err_slave_config;
733 	}
734 
735 	cfg.direction = DMA_MEM_TO_DEV;
736 	ret = dmaengine_slave_config(dma->chan_tx, &cfg);
737 	if (ret) {
738 		dev_err_probe(dev, ret, "can't configure tx dma channel\n");
739 		goto err_slave_config;
740 	}
741 
742 	dspi->dma = dma;
743 	init_completion(&dma->cmd_tx_complete);
744 	init_completion(&dma->cmd_rx_complete);
745 
746 	return 0;
747 
748 err_slave_config:
749 	dma_free_noncoherent(dma->chan_rx->device->dev, dma->bufsize,
750 			     dma->rx_dma_buf, dma->rx_dma_phys,
751 			     DMA_FROM_DEVICE);
752 err_rx_dma_buf:
753 	dma_free_noncoherent(dma->chan_tx->device->dev, dma->bufsize,
754 			     dma->tx_dma_buf, dma->tx_dma_phys, DMA_TO_DEVICE);
755 err_tx_dma_buf:
756 	dma_release_channel(dma->chan_tx);
757 err_tx_channel:
758 	dma_release_channel(dma->chan_rx);
759 
760 	devm_kfree(dev, dma);
761 	dspi->dma = NULL;
762 
763 	return ret;
764 }
765 
766 static void dspi_release_dma(struct fsl_dspi *dspi)
767 {
768 	struct fsl_dspi_dma *dma = dspi->dma;
769 
770 	if (!dma)
771 		return;
772 
773 	if (dma->chan_tx) {
774 		dma_free_noncoherent(dma->chan_tx->device->dev, dma->bufsize,
775 				     dma->tx_dma_buf, dma->tx_dma_phys,
776 				     DMA_TO_DEVICE);
777 		dma_release_channel(dma->chan_tx);
778 	}
779 
780 	if (dma->chan_rx) {
781 		dma_free_noncoherent(dma->chan_rx->device->dev, dma->bufsize,
782 				     dma->rx_dma_buf, dma->rx_dma_phys,
783 				     DMA_FROM_DEVICE);
784 		dma_release_channel(dma->chan_rx);
785 	}
786 }
787 #else
788 static void dspi_dma_xfer(struct fsl_dspi *dspi)
789 {
790 	dspi->cur_msg->status = -EINVAL;
791 }
792 static int dspi_request_dma(struct fsl_dspi *dspi, phys_addr_t phy_addr)
793 {
794 	dev_err(&dspi->pdev->dev, "DMA support not enabled in kernel\n");
795 	return -EINVAL;
796 }
797 static void dspi_release_dma(struct fsl_dspi *dspi) {}
798 #endif
799 
800 static void hz_to_spi_baud(char *pbr, char *br, int speed_hz,
801 			   unsigned long clkrate, bool mtf_enabled)
802 {
803 	/* Valid baud rate pre-scaler values */
804 	int pbr_tbl[4] = {2, 3, 5, 7};
805 	int brs[16] = {	2,	4,	6,	8,
806 			16,	32,	64,	128,
807 			256,	512,	1024,	2048,
808 			4096,	8192,	16384,	32768 };
809 	int scale_needed, scale, minscale = INT_MAX;
810 	int i, j;
811 
812 	scale_needed = clkrate / speed_hz;
813 	if (clkrate % speed_hz)
814 		scale_needed++;
815 
816 	for (i = 0; i < ARRAY_SIZE(brs); i++)
817 		for (j = 0; j < ARRAY_SIZE(pbr_tbl); j++) {
818 			if (mtf_enabled) {
819 				/* In MTF mode DBR=1 so frequency is doubled */
820 				scale = (brs[i] * pbr_tbl[j]) / 2;
821 			} else {
822 				scale = brs[i] * pbr_tbl[j];
823 			}
824 
825 			if (scale >= scale_needed) {
826 				if (scale < minscale) {
827 					minscale = scale;
828 					*br = i;
829 					*pbr = j;
830 				}
831 				break;
832 			}
833 		}
834 
835 	if (minscale == INT_MAX) {
836 		pr_warn("Can not find valid baud rate,speed_hz is %d,clkrate is %ld, we use the max prescaler value.\n",
837 			speed_hz, clkrate);
838 		*pbr = ARRAY_SIZE(pbr_tbl) - 1;
839 		*br =  ARRAY_SIZE(brs) - 1;
840 	}
841 }
842 
843 static void ns_delay_scale(char *psc, char *sc, int delay_ns,
844 			   unsigned long clkrate)
845 {
846 	int scale_needed, scale, minscale = INT_MAX;
847 	int pscale_tbl[4] = {1, 3, 5, 7};
848 	u32 remainder;
849 	int i, j;
850 
851 	scale_needed = div_u64_rem((u64)delay_ns * clkrate, NSEC_PER_SEC,
852 				   &remainder);
853 	if (remainder)
854 		scale_needed++;
855 
856 	for (i = 0; i < ARRAY_SIZE(pscale_tbl); i++)
857 		for (j = 0; j <= SPI_CTAR_SCALE_BITS; j++) {
858 			scale = pscale_tbl[i] * (2 << j);
859 			if (scale >= scale_needed) {
860 				if (scale < minscale) {
861 					minscale = scale;
862 					*psc = i;
863 					*sc = j;
864 				}
865 				break;
866 			}
867 		}
868 
869 	if (minscale == INT_MAX) {
870 		pr_warn("Cannot find correct scale values for %dns delay at clkrate %ld, using max prescaler value",
871 			delay_ns, clkrate);
872 		*psc = ARRAY_SIZE(pscale_tbl) - 1;
873 		*sc = SPI_CTAR_SCALE_BITS;
874 	}
875 }
876 
877 static void dspi_pushr_cmd_write(struct fsl_dspi *dspi, u16 cmd)
878 {
879 	/*
880 	 * The only time when the PCS doesn't need continuation after this word
881 	 * is when it's last. We need to look ahead, because we actually call
882 	 * dspi_pop_tx (the function that decrements dspi->len) _after_
883 	 * dspi_pushr_cmd_write with XSPI mode. As for how much in advance? One
884 	 * word is enough. If there's more to transmit than that,
885 	 * dspi_xspi_write will know to split the FIFO writes in 2, and
886 	 * generate a new PUSHR command with the final word that will have PCS
887 	 * deasserted (not continued) here.
888 	 */
889 	if (dspi->len > dspi->oper_word_size)
890 		cmd |= SPI_PUSHR_CMD_CONT;
891 	regmap_write(dspi->regmap_pushr, dspi->pushr_cmd, cmd);
892 }
893 
894 static void dspi_pushr_txdata_write(struct fsl_dspi *dspi, u16 txdata)
895 {
896 	regmap_write(dspi->regmap_pushr, dspi->pushr_tx, txdata);
897 }
898 
899 static void dspi_xspi_fifo_write(struct fsl_dspi *dspi, int num_words)
900 {
901 	int num_bytes = num_words * dspi->oper_word_size;
902 	u16 tx_cmd = dspi->tx_cmd;
903 
904 	/*
905 	 * If the PCS needs to de-assert (i.e. we're at the end of the buffer
906 	 * and cs_change does not want the PCS to stay on), then we need a new
907 	 * PUSHR command, since this one (for the body of the buffer)
908 	 * necessarily has the CONT bit set.
909 	 * So send one word less during this go, to force a split and a command
910 	 * with a single word next time, when CONT will be unset.
911 	 */
912 	if (!(dspi->tx_cmd & SPI_PUSHR_CMD_CONT) && num_bytes == dspi->len)
913 		tx_cmd |= SPI_PUSHR_CMD_EOQ;
914 
915 	/* Update CTARE */
916 	regmap_write(dspi->regmap, SPI_CTARE(0),
917 		     SPI_FRAME_EBITS(dspi->oper_bits_per_word) |
918 		     SPI_CTARE_DTCP(num_words));
919 
920 	/*
921 	 * Write the CMD FIFO entry first, and then the two
922 	 * corresponding TX FIFO entries (or one...).
923 	 */
924 	dspi_pushr_cmd_write(dspi, tx_cmd);
925 
926 	/* Fill TX FIFO with as many transfers as possible */
927 	while (num_words--) {
928 		u32 data = dspi_pop_tx(dspi);
929 
930 		dspi_pushr_txdata_write(dspi, data & 0xFFFF);
931 		if (dspi->oper_bits_per_word > 16)
932 			dspi_pushr_txdata_write(dspi, data >> 16);
933 	}
934 }
935 
936 static u32 dspi_popr_read(struct fsl_dspi *dspi)
937 {
938 	u32 rxdata = 0;
939 
940 	regmap_read(dspi->regmap, SPI_POPR, &rxdata);
941 	return rxdata;
942 }
943 
944 static void dspi_fifo_read(struct fsl_dspi *dspi)
945 {
946 	int num_fifo_entries = dspi->words_in_flight;
947 
948 	/* Read one FIFO entry and push to rx buffer */
949 	while (num_fifo_entries--)
950 		dspi_push_rx(dspi, dspi_popr_read(dspi));
951 }
952 
953 static void dspi_setup_accel(struct fsl_dspi *dspi)
954 {
955 	struct spi_transfer *xfer = dspi->cur_transfer;
956 	bool odd = !!(dspi->len & 1);
957 
958 	/*
959 	 * No accel for DMA transfers or frames not multiples of 8 bits at the
960 	 * moment.
961 	 */
962 	if (dspi->devtype_data->trans_mode == DSPI_DMA_MODE ||
963 	    xfer->bits_per_word % 8)
964 		goto no_accel;
965 
966 	if (!odd && dspi->len <= dspi->devtype_data->fifo_size * 2) {
967 		dspi->oper_bits_per_word = 16;
968 	} else if (odd && dspi->len <= dspi->devtype_data->fifo_size) {
969 		dspi->oper_bits_per_word = 8;
970 	} else {
971 		/* Start off with maximum supported by hardware */
972 		dspi->oper_bits_per_word = 32;
973 
974 		/*
975 		 * And go down only if the buffer can't be sent with
976 		 * words this big
977 		 */
978 		do {
979 			if (dspi->len >= DIV_ROUND_UP(dspi->oper_bits_per_word, 8))
980 				break;
981 
982 			dspi->oper_bits_per_word /= 2;
983 		} while (dspi->oper_bits_per_word > 8);
984 	}
985 
986 	if (xfer->bits_per_word == 8 && dspi->oper_bits_per_word == 32) {
987 		dspi->dev_to_host = dspi_8on32_dev_to_host;
988 		dspi->host_to_dev = dspi_8on32_host_to_dev;
989 	} else if (xfer->bits_per_word == 8 && dspi->oper_bits_per_word == 16) {
990 		dspi->dev_to_host = dspi_8on16_dev_to_host;
991 		dspi->host_to_dev = dspi_8on16_host_to_dev;
992 	} else if (xfer->bits_per_word == 16 && dspi->oper_bits_per_word == 32) {
993 		dspi->dev_to_host = dspi_16on32_dev_to_host;
994 		dspi->host_to_dev = dspi_16on32_host_to_dev;
995 	} else {
996 no_accel:
997 		dspi->dev_to_host = dspi_native_dev_to_host;
998 		dspi->host_to_dev = dspi_native_host_to_dev;
999 		dspi->oper_bits_per_word = xfer->bits_per_word;
1000 	}
1001 
1002 	dspi->oper_word_size = DIV_ROUND_UP(dspi->oper_bits_per_word, 8);
1003 
1004 	/*
1005 	 * Update CTAR here (code is common for XSPI and DMA modes).
1006 	 * We will update CTARE in the portion specific to XSPI, when we
1007 	 * also know the preload value (DTCP).
1008 	 */
1009 	regmap_write(dspi->regmap, SPI_CTAR(0),
1010 		     dspi->cur_chip->ctar_val |
1011 		     SPI_FRAME_BITS(dspi->oper_bits_per_word));
1012 }
1013 
1014 static void dspi_fifo_write(struct fsl_dspi *dspi)
1015 {
1016 	int num_fifo_entries = dspi->devtype_data->fifo_size;
1017 	struct spi_transfer *xfer = dspi->cur_transfer;
1018 	struct spi_message *msg = dspi->cur_msg;
1019 	int num_words, num_bytes;
1020 
1021 	dspi_setup_accel(dspi);
1022 
1023 	/* In XSPI mode each 32-bit word occupies 2 TX FIFO entries */
1024 	if (dspi->oper_word_size == 4)
1025 		num_fifo_entries /= 2;
1026 
1027 	/*
1028 	 * Integer division intentionally trims off odd (or non-multiple of 4)
1029 	 * numbers of bytes at the end of the buffer, which will be sent next
1030 	 * time using a smaller oper_word_size.
1031 	 */
1032 	num_words = dspi->len / dspi->oper_word_size;
1033 	if (num_words > num_fifo_entries)
1034 		num_words = num_fifo_entries;
1035 
1036 	/* Update total number of bytes that were transferred */
1037 	num_bytes = num_words * dspi->oper_word_size;
1038 	msg->actual_length += num_bytes;
1039 	dspi->progress += num_bytes / DIV_ROUND_UP(xfer->bits_per_word, 8);
1040 
1041 	/*
1042 	 * Update shared variable for use in the next interrupt (both in
1043 	 * dspi_fifo_read and in dspi_fifo_write).
1044 	 */
1045 	dspi->words_in_flight = num_words;
1046 
1047 	spi_take_timestamp_pre(dspi->ctlr, xfer, dspi->progress, !dspi->irq);
1048 
1049 	dspi_xspi_fifo_write(dspi, num_words);
1050 	/*
1051 	 * Everything after this point is in a potential race with the next
1052 	 * interrupt, so we must never use dspi->words_in_flight again since it
1053 	 * might already be modified by the next dspi_fifo_write.
1054 	 */
1055 
1056 	spi_take_timestamp_post(dspi->ctlr, dspi->cur_transfer,
1057 				dspi->progress, !dspi->irq);
1058 }
1059 
1060 /*
1061  * Read the previous transfer from the FIFO and transmit the next one.
1062  *
1063  * Returns false if the buffer to be transmitted is empty, and true if there is
1064  * still data to transmit.
1065  */
1066 static bool dspi_rxtx(struct fsl_dspi *dspi)
1067 {
1068 	dspi_fifo_read(dspi);
1069 
1070 	if (!dspi->len)
1071 		/* Success! */
1072 		return false;
1073 
1074 	dspi_fifo_write(dspi);
1075 
1076 	return true;
1077 }
1078 
1079 static void dspi_poll(struct fsl_dspi *dspi)
1080 {
1081 	int tries;
1082 	int err = 0;
1083 	u32 spi_sr;
1084 
1085 	do {
1086 		for (tries = 1000; tries > 0; --tries) {
1087 			regmap_read(dspi->regmap, SPI_SR, &spi_sr);
1088 			regmap_write(dspi->regmap, SPI_SR, spi_sr);
1089 
1090 			dspi->cur_msg->status = dspi_fifo_error(dspi, spi_sr);
1091 			if (dspi->cur_msg->status)
1092 				return;
1093 			if (spi_sr & SPI_SR_CMDTCF)
1094 				break;
1095 		}
1096 		if (!tries) {
1097 			err = -ETIMEDOUT;
1098 			break;
1099 		}
1100 	} while (dspi_rxtx(dspi));
1101 
1102 	dspi->cur_msg->status = err;
1103 }
1104 
1105 static irqreturn_t dspi_interrupt(int irq, void *dev_id)
1106 {
1107 	struct fsl_dspi *dspi = (struct fsl_dspi *)dev_id;
1108 	int status;
1109 	u32 spi_sr;
1110 
1111 	regmap_read(dspi->regmap, SPI_SR, &spi_sr);
1112 	regmap_write(dspi->regmap, SPI_SR, spi_sr);
1113 
1114 	if (!(spi_sr & SPI_SR_CMDTCF))
1115 		return IRQ_NONE;
1116 
1117 	status = dspi_fifo_error(dspi, spi_sr);
1118 	if (status) {
1119 		if (dspi->cur_msg)
1120 			WRITE_ONCE(dspi->cur_msg->status, status);
1121 		complete(&dspi->xfer_done);
1122 		return IRQ_HANDLED;
1123 	}
1124 
1125 	if (dspi_rxtx(dspi) == false) {
1126 		if (dspi->cur_msg)
1127 			WRITE_ONCE(dspi->cur_msg->status, 0);
1128 		complete(&dspi->xfer_done);
1129 	}
1130 
1131 	return IRQ_HANDLED;
1132 }
1133 
1134 static void dspi_assert_cs(struct spi_device *spi, bool *cs)
1135 {
1136 	if (!spi_get_csgpiod(spi, 0) || *cs)
1137 		return;
1138 
1139 	gpiod_set_value_cansleep(spi_get_csgpiod(spi, 0), true);
1140 	*cs = true;
1141 }
1142 
1143 static void dspi_deassert_cs(struct spi_device *spi, bool *cs)
1144 {
1145 	if (!spi_get_csgpiod(spi, 0) || !*cs)
1146 		return;
1147 
1148 	gpiod_set_value_cansleep(spi_get_csgpiod(spi, 0), false);
1149 	*cs = false;
1150 }
1151 
1152 static int dspi_transfer_one_message(struct spi_controller *ctlr,
1153 				     struct spi_message *message)
1154 {
1155 	struct fsl_dspi *dspi = spi_controller_get_devdata(ctlr);
1156 	struct spi_device *spi = message->spi;
1157 	struct spi_transfer *transfer;
1158 	bool cs = false;
1159 	u32 val = 0;
1160 	bool cs_change = false;
1161 
1162 	message->actual_length = 0;
1163 
1164 	/* Put DSPI in running mode if halted. */
1165 	regmap_read(dspi->regmap, SPI_MCR, &val);
1166 	if (val & SPI_MCR_HALT) {
1167 		regmap_update_bits(dspi->regmap, SPI_MCR, SPI_MCR_HALT, 0);
1168 		while (regmap_read(dspi->regmap, SPI_SR, &val) >= 0 &&
1169 		       !(val & SPI_SR_TXRXS))
1170 			;
1171 	}
1172 
1173 	list_for_each_entry(transfer, &message->transfers, transfer_list) {
1174 		dspi->cur_transfer = transfer;
1175 		dspi->cur_msg = message;
1176 		dspi->cur_chip = spi_get_ctldata(spi);
1177 
1178 		dspi_assert_cs(spi, &cs);
1179 
1180 		/* Prepare command word for CMD FIFO */
1181 		dspi->tx_cmd = SPI_PUSHR_CMD_CTAS(0);
1182 		if (!spi_get_csgpiod(spi, 0))
1183 			dspi->tx_cmd |= SPI_PUSHR_CMD_PCS(spi_get_chipselect(spi, 0));
1184 
1185 		if (list_is_last(&dspi->cur_transfer->transfer_list,
1186 				 &dspi->cur_msg->transfers)) {
1187 			/* Leave PCS activated after last transfer when
1188 			 * cs_change is set.
1189 			 */
1190 			if (transfer->cs_change)
1191 				dspi->tx_cmd |= SPI_PUSHR_CMD_CONT;
1192 		} else {
1193 			/* Keep PCS active between transfers in same message
1194 			 * when cs_change is not set, and de-activate PCS
1195 			 * between transfers in the same message when
1196 			 * cs_change is set.
1197 			 */
1198 			if (!transfer->cs_change)
1199 				dspi->tx_cmd |= SPI_PUSHR_CMD_CONT;
1200 		}
1201 
1202 		cs_change = transfer->cs_change;
1203 		dspi->tx = transfer->tx_buf;
1204 		dspi->rx = transfer->rx_buf;
1205 		dspi->len = transfer->len;
1206 		dspi->progress = 0;
1207 
1208 		regmap_update_bits(dspi->regmap, SPI_MCR,
1209 				   SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF,
1210 				   SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF);
1211 
1212 		regmap_write(dspi->regmap, SPI_SR, SPI_SR_CLEAR);
1213 
1214 		spi_take_timestamp_pre(dspi->ctlr, dspi->cur_transfer,
1215 				       dspi->progress, !dspi->irq);
1216 
1217 		if (dspi->devtype_data->trans_mode == DSPI_DMA_MODE) {
1218 			dspi_dma_xfer(dspi);
1219 		} else {
1220 			/*
1221 			 * Reinitialize the completion before transferring data
1222 			 * to avoid the case where it might remain in the done
1223 			 * state due to a spurious interrupt from a previous
1224 			 * transfer. This could falsely signal that the current
1225 			 * transfer has completed.
1226 			 */
1227 			if (dspi->irq)
1228 				reinit_completion(&dspi->xfer_done);
1229 
1230 			dspi_fifo_write(dspi);
1231 
1232 			if (dspi->irq)
1233 				wait_for_completion(&dspi->xfer_done);
1234 			else
1235 				dspi_poll(dspi);
1236 		}
1237 		if (READ_ONCE(message->status))
1238 			break;
1239 
1240 		spi_transfer_delay_exec(transfer);
1241 
1242 		if (!(dspi->tx_cmd & SPI_PUSHR_CMD_CONT))
1243 			dspi_deassert_cs(spi, &cs);
1244 	}
1245 
1246 	dspi->cur_msg = NULL;
1247 	if (message->status || !cs_change) {
1248 		/* Put DSPI in stop mode */
1249 		regmap_update_bits(dspi->regmap, SPI_MCR,
1250 				   SPI_MCR_HALT, SPI_MCR_HALT);
1251 		while (regmap_read(dspi->regmap, SPI_SR, &val) >= 0 &&
1252 		       val & SPI_SR_TXRXS)
1253 			;
1254 	}
1255 
1256 	spi_finalize_current_message(ctlr);
1257 
1258 	return message->status;
1259 }
1260 
1261 static int dspi_set_mtf(struct fsl_dspi *dspi)
1262 {
1263 	if (spi_controller_is_target(dspi->ctlr))
1264 		return 0;
1265 
1266 	if (dspi->mtf_enabled)
1267 		regmap_update_bits(dspi->regmap, SPI_MCR, SPI_MCR_MTFE,
1268 				   SPI_MCR_MTFE);
1269 	else
1270 		regmap_update_bits(dspi->regmap, SPI_MCR, SPI_MCR_MTFE, 0);
1271 
1272 	return 0;
1273 }
1274 
1275 static int dspi_setup(struct spi_device *spi)
1276 {
1277 	struct fsl_dspi *dspi = spi_controller_get_devdata(spi->controller);
1278 	u32 period_ns = DIV_ROUND_UP(NSEC_PER_SEC, spi->max_speed_hz);
1279 	unsigned char br = 0, pbr = 0, pcssck = 0, cssck = 0;
1280 	u32 quarter_period_ns = DIV_ROUND_UP(period_ns, 4);
1281 	u32 cs_sck_delay = 0, sck_cs_delay = 0;
1282 	struct fsl_dspi_platform_data *pdata;
1283 	unsigned char pasc = 0, asc = 0;
1284 	struct gpio_desc *gpio_cs;
1285 	struct chip_data *chip;
1286 	unsigned long clkrate;
1287 	bool cs = true;
1288 	int val;
1289 
1290 	/* Only alloc on first setup */
1291 	chip = spi_get_ctldata(spi);
1292 	if (chip == NULL) {
1293 		chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
1294 		if (!chip)
1295 			return -ENOMEM;
1296 	}
1297 
1298 	pdata = dev_get_platdata(&dspi->pdev->dev);
1299 
1300 	if (!pdata) {
1301 		val = spi_delay_to_ns(&spi->cs_setup, NULL);
1302 		cs_sck_delay = val >= 0 ? val : 0;
1303 		if (!cs_sck_delay)
1304 			of_property_read_u32(spi->dev.of_node,
1305 					     "fsl,spi-cs-sck-delay",
1306 					     &cs_sck_delay);
1307 
1308 		val = spi_delay_to_ns(&spi->cs_hold, NULL);
1309 		sck_cs_delay =  val >= 0 ? val : 0;
1310 		if (!sck_cs_delay)
1311 			of_property_read_u32(spi->dev.of_node,
1312 					     "fsl,spi-sck-cs-delay",
1313 					     &sck_cs_delay);
1314 	} else {
1315 		cs_sck_delay = pdata->cs_sck_delay;
1316 		sck_cs_delay = pdata->sck_cs_delay;
1317 	}
1318 
1319 	/* Since tCSC and tASC apply to continuous transfers too, avoid SCK
1320 	 * glitches of half a cycle by never allowing tCSC + tASC to go below
1321 	 * half a SCK period.
1322 	 */
1323 	if (cs_sck_delay < quarter_period_ns)
1324 		cs_sck_delay = quarter_period_ns;
1325 	if (sck_cs_delay < quarter_period_ns)
1326 		sck_cs_delay = quarter_period_ns;
1327 
1328 	dev_dbg(&spi->dev,
1329 		"DSPI controller timing params: CS-to-SCK delay %u ns, SCK-to-CS delay %u ns\n",
1330 		cs_sck_delay, sck_cs_delay);
1331 
1332 	clkrate = clk_get_rate(dspi->clk);
1333 
1334 	if (is_s32g_dspi(dspi) && spi->max_speed_hz > SPI_25MHZ)
1335 		dspi->mtf_enabled = true;
1336 	else
1337 		dspi->mtf_enabled = false;
1338 
1339 	dspi_set_mtf(dspi);
1340 
1341 	hz_to_spi_baud(&pbr, &br, spi->max_speed_hz, clkrate,
1342 		       dspi->mtf_enabled);
1343 
1344 	/* Set PCS to SCK delay scale values */
1345 	ns_delay_scale(&pcssck, &cssck, cs_sck_delay, clkrate);
1346 
1347 	/* Set After SCK delay scale values */
1348 	ns_delay_scale(&pasc, &asc, sck_cs_delay, clkrate);
1349 
1350 	chip->ctar_val = 0;
1351 	if (spi->mode & SPI_CPOL)
1352 		chip->ctar_val |= SPI_CTAR_CPOL;
1353 	if (spi->mode & SPI_CPHA)
1354 		chip->ctar_val |= SPI_CTAR_CPHA;
1355 
1356 	if (!spi_controller_is_target(dspi->ctlr)) {
1357 		chip->ctar_val |= SPI_CTAR_PCSSCK(pcssck) |
1358 				  SPI_CTAR_CSSCK(cssck) |
1359 				  SPI_CTAR_PASC(pasc) |
1360 				  SPI_CTAR_ASC(asc) |
1361 				  SPI_CTAR_PBR(pbr) |
1362 				  SPI_CTAR_BR(br);
1363 
1364 		if (dspi->mtf_enabled)
1365 			chip->ctar_val |= SPI_CTAR_DBR;
1366 
1367 		if (spi->mode & SPI_LSB_FIRST)
1368 			chip->ctar_val |= SPI_CTAR_LSBFE;
1369 	}
1370 
1371 	gpio_cs = spi_get_csgpiod(spi, 0);
1372 	if (gpio_cs)
1373 		gpiod_direction_output(gpio_cs, false);
1374 
1375 	dspi_deassert_cs(spi, &cs);
1376 
1377 	spi_set_ctldata(spi, chip);
1378 
1379 	return 0;
1380 }
1381 
1382 static void dspi_cleanup(struct spi_device *spi)
1383 {
1384 	struct chip_data *chip = spi_get_ctldata(spi);
1385 
1386 	dev_dbg(&spi->dev, "spi_device %u.%u cleanup\n",
1387 		spi->controller->bus_num, spi_get_chipselect(spi, 0));
1388 
1389 	kfree(chip);
1390 }
1391 
1392 static const struct of_device_id fsl_dspi_dt_ids[] = {
1393 	{
1394 		.compatible = "fsl,vf610-dspi",
1395 		.data = &devtype_data[VF610],
1396 	}, {
1397 		.compatible = "fsl,ls1021a-v1.0-dspi",
1398 		.data = &devtype_data[LS1021A],
1399 	}, {
1400 		.compatible = "fsl,ls1012a-dspi",
1401 		.data = &devtype_data[LS1012A],
1402 	}, {
1403 		.compatible = "fsl,ls1028a-dspi",
1404 		.data = &devtype_data[LS1028A],
1405 	}, {
1406 		.compatible = "fsl,ls1043a-dspi",
1407 		.data = &devtype_data[LS1043A],
1408 	}, {
1409 		.compatible = "fsl,ls1046a-dspi",
1410 		.data = &devtype_data[LS1046A],
1411 	}, {
1412 		.compatible = "fsl,ls2080a-dspi",
1413 		.data = &devtype_data[LS2080A],
1414 	}, {
1415 		.compatible = "fsl,ls2085a-dspi",
1416 		.data = &devtype_data[LS2085A],
1417 	}, {
1418 		.compatible = "fsl,lx2160a-dspi",
1419 		.data = &devtype_data[LX2160A],
1420 	}, {
1421 		.compatible = "nxp,s32g2-dspi",
1422 		.data = &devtype_data[S32G],
1423 	},
1424 	{ /* sentinel */ }
1425 };
1426 MODULE_DEVICE_TABLE(of, fsl_dspi_dt_ids);
1427 
1428 static int dspi_init(struct fsl_dspi *dspi)
1429 {
1430 	unsigned int mcr;
1431 
1432 	/* Set idle states for all chip select signals to high */
1433 	mcr = SPI_MCR_PCSIS(GENMASK(dspi->ctlr->max_native_cs - 1, 0));
1434 
1435 	if (dspi->devtype_data->trans_mode == DSPI_XSPI_MODE)
1436 		mcr |= SPI_MCR_XSPI;
1437 	if (!spi_controller_is_target(dspi->ctlr))
1438 		mcr |= SPI_MCR_HOST;
1439 
1440 	mcr |= SPI_MCR_HALT;
1441 
1442 	regmap_write(dspi->regmap, SPI_MCR, mcr);
1443 	regmap_write(dspi->regmap, SPI_SR, SPI_SR_CLEAR);
1444 
1445 	switch (dspi->devtype_data->trans_mode) {
1446 	case DSPI_XSPI_MODE:
1447 		regmap_write(dspi->regmap, SPI_RSER, SPI_RSER_CMDTCFE);
1448 		break;
1449 	case DSPI_DMA_MODE:
1450 		regmap_write(dspi->regmap, SPI_RSER,
1451 			     SPI_RSER_TFFFE | SPI_RSER_TFFFD |
1452 			     SPI_RSER_RFDFE | SPI_RSER_RFDFD);
1453 		break;
1454 	default:
1455 		dev_err(&dspi->pdev->dev, "unsupported trans_mode %u\n",
1456 			dspi->devtype_data->trans_mode);
1457 		return -EINVAL;
1458 	}
1459 
1460 	return 0;
1461 }
1462 
1463 #ifdef CONFIG_PM_SLEEP
1464 static int dspi_suspend(struct device *dev)
1465 {
1466 	struct fsl_dspi *dspi = dev_get_drvdata(dev);
1467 
1468 	if (dspi->irq)
1469 		disable_irq(dspi->irq);
1470 	spi_controller_suspend(dspi->ctlr);
1471 	clk_disable_unprepare(dspi->clk);
1472 
1473 	pinctrl_pm_select_sleep_state(dev);
1474 
1475 	return 0;
1476 }
1477 
1478 static int dspi_resume(struct device *dev)
1479 {
1480 	struct fsl_dspi *dspi = dev_get_drvdata(dev);
1481 	int ret;
1482 
1483 	pinctrl_pm_select_default_state(dev);
1484 
1485 	ret = clk_prepare_enable(dspi->clk);
1486 	if (ret)
1487 		return ret;
1488 	spi_controller_resume(dspi->ctlr);
1489 
1490 	ret = dspi_init(dspi);
1491 	if (ret) {
1492 		dev_err(dev, "failed to initialize dspi during resume\n");
1493 		return ret;
1494 	}
1495 
1496 	dspi_set_mtf(dspi);
1497 
1498 	if (dspi->irq)
1499 		enable_irq(dspi->irq);
1500 
1501 	return 0;
1502 }
1503 #endif /* CONFIG_PM_SLEEP */
1504 
1505 static SIMPLE_DEV_PM_OPS(dspi_pm, dspi_suspend, dspi_resume);
1506 
1507 static int dspi_target_abort(struct spi_controller *host)
1508 {
1509 	struct fsl_dspi *dspi = spi_controller_get_devdata(host);
1510 
1511 	/*
1512 	 * Terminate all pending DMA transactions for the SPI working
1513 	 * in TARGET mode.
1514 	 */
1515 	if (dspi->devtype_data->trans_mode == DSPI_DMA_MODE) {
1516 		dmaengine_terminate_sync(dspi->dma->chan_rx);
1517 		dmaengine_terminate_sync(dspi->dma->chan_tx);
1518 	}
1519 
1520 	/* Clear the internal DSPI RX and TX FIFO buffers */
1521 	regmap_update_bits(dspi->regmap, SPI_MCR,
1522 			   SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF,
1523 			   SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF);
1524 
1525 	return 0;
1526 }
1527 
1528 static int dspi_probe(struct platform_device *pdev)
1529 {
1530 	struct device_node *np = pdev->dev.of_node;
1531 	struct fsl_dspi_platform_data *pdata;
1532 	struct spi_controller *ctlr;
1533 	int ret, cs_num, bus_num = -1;
1534 	struct fsl_dspi *dspi;
1535 	struct resource *res;
1536 	void __iomem *base;
1537 	bool big_endian;
1538 
1539 	dspi = devm_kzalloc(&pdev->dev, sizeof(*dspi), GFP_KERNEL);
1540 	if (!dspi)
1541 		return -ENOMEM;
1542 
1543 	if (of_property_read_bool(np, "spi-slave"))
1544 		ctlr = spi_alloc_target(&pdev->dev, 0);
1545 	else
1546 		ctlr = spi_alloc_host(&pdev->dev, 0);
1547 	if (!ctlr)
1548 		return -ENOMEM;
1549 
1550 	spi_controller_set_devdata(ctlr, dspi);
1551 	platform_set_drvdata(pdev, dspi);
1552 
1553 	dspi->pdev = pdev;
1554 	dspi->ctlr = ctlr;
1555 
1556 	ctlr->setup = dspi_setup;
1557 	ctlr->transfer_one_message = dspi_transfer_one_message;
1558 	ctlr->dev.of_node = pdev->dev.of_node;
1559 
1560 	ctlr->cleanup = dspi_cleanup;
1561 	ctlr->target_abort = dspi_target_abort;
1562 	ctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;
1563 	ctlr->use_gpio_descriptors = true;
1564 
1565 	pdata = dev_get_platdata(&pdev->dev);
1566 	if (pdata) {
1567 		ctlr->num_chipselect = ctlr->max_native_cs = pdata->cs_num;
1568 		ctlr->bus_num = pdata->bus_num;
1569 
1570 		/* Only Coldfire uses platform data */
1571 		dspi->devtype_data = &devtype_data[MCF5441X];
1572 		big_endian = true;
1573 	} else {
1574 
1575 		ret = of_property_read_u32(np, "spi-num-chipselects", &cs_num);
1576 		if (ret < 0) {
1577 			dev_err(&pdev->dev, "can't get spi-num-chipselects\n");
1578 			goto out_ctlr_put;
1579 		}
1580 		ctlr->num_chipselect = ctlr->max_native_cs = cs_num;
1581 
1582 		of_property_read_u32(np, "bus-num", &bus_num);
1583 		ctlr->bus_num = bus_num;
1584 
1585 		dspi->devtype_data = of_device_get_match_data(&pdev->dev);
1586 		if (!dspi->devtype_data) {
1587 			dev_err(&pdev->dev, "can't get devtype_data\n");
1588 			ret = -EFAULT;
1589 			goto out_ctlr_put;
1590 		}
1591 
1592 		big_endian = of_device_is_big_endian(np);
1593 	}
1594 	if (big_endian) {
1595 		dspi->pushr_cmd = 0;
1596 		dspi->pushr_tx = 2;
1597 	} else {
1598 		dspi->pushr_cmd = 2;
1599 		dspi->pushr_tx = 0;
1600 	}
1601 
1602 	if (spi_controller_is_target(ctlr) && is_s32g_dspi(dspi))
1603 		dspi->devtype_data = &devtype_data[S32G_TARGET];
1604 
1605 	if (dspi->devtype_data->trans_mode == DSPI_XSPI_MODE)
1606 		ctlr->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1607 	else
1608 		ctlr->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16);
1609 
1610 	base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
1611 	if (IS_ERR(base)) {
1612 		ret = PTR_ERR(base);
1613 		goto out_ctlr_put;
1614 	}
1615 
1616 	dspi->regmap = devm_regmap_init_mmio(&pdev->dev, base,
1617 					     dspi->devtype_data->regmap);
1618 	if (IS_ERR(dspi->regmap)) {
1619 		dev_err(&pdev->dev, "failed to init regmap: %ld\n",
1620 				PTR_ERR(dspi->regmap));
1621 		ret = PTR_ERR(dspi->regmap);
1622 		goto out_ctlr_put;
1623 	}
1624 
1625 	if (dspi->devtype_data->trans_mode == DSPI_XSPI_MODE) {
1626 		dspi->regmap_pushr = devm_regmap_init_mmio(
1627 			&pdev->dev, base + SPI_PUSHR,
1628 			&dspi_regmap_config[DSPI_PUSHR]);
1629 		if (IS_ERR(dspi->regmap_pushr)) {
1630 			dev_err(&pdev->dev,
1631 				"failed to init pushr regmap: %ld\n",
1632 				PTR_ERR(dspi->regmap_pushr));
1633 			ret = PTR_ERR(dspi->regmap_pushr);
1634 			goto out_ctlr_put;
1635 		}
1636 	}
1637 
1638 	dspi->clk = devm_clk_get_enabled(&pdev->dev, "dspi");
1639 	if (IS_ERR(dspi->clk)) {
1640 		ret = PTR_ERR(dspi->clk);
1641 		dev_err(&pdev->dev, "unable to get clock\n");
1642 		goto out_ctlr_put;
1643 	}
1644 
1645 	ret = dspi_init(dspi);
1646 	if (ret)
1647 		goto out_ctlr_put;
1648 
1649 	dspi->irq = platform_get_irq(pdev, 0);
1650 	if (dspi->irq <= 0) {
1651 		dev_info(&pdev->dev,
1652 			 "can't get platform irq, using poll mode\n");
1653 		dspi->irq = 0;
1654 		goto poll_mode;
1655 	}
1656 
1657 	init_completion(&dspi->xfer_done);
1658 
1659 	ret = request_threaded_irq(dspi->irq, dspi_interrupt, NULL,
1660 				   IRQF_SHARED, pdev->name, dspi);
1661 	if (ret < 0) {
1662 		dev_err(&pdev->dev, "Unable to attach DSPI interrupt\n");
1663 		goto out_ctlr_put;
1664 	}
1665 
1666 poll_mode:
1667 
1668 	if (dspi->devtype_data->trans_mode == DSPI_DMA_MODE) {
1669 		ret = dspi_request_dma(dspi, res->start);
1670 		if (ret < 0) {
1671 			dev_err(&pdev->dev, "can't get dma channels\n");
1672 			goto out_free_irq;
1673 		}
1674 	}
1675 
1676 	ctlr->max_speed_hz =
1677 		clk_get_rate(dspi->clk) / dspi->devtype_data->max_clock_factor;
1678 
1679 	if (dspi->devtype_data->trans_mode != DSPI_DMA_MODE)
1680 		ctlr->ptp_sts_supported = true;
1681 
1682 	ret = spi_register_controller(ctlr);
1683 	if (ret != 0) {
1684 		dev_err(&pdev->dev, "Problem registering DSPI ctlr\n");
1685 		goto out_release_dma;
1686 	}
1687 
1688 	return ret;
1689 
1690 out_release_dma:
1691 	dspi_release_dma(dspi);
1692 out_free_irq:
1693 	if (dspi->irq)
1694 		free_irq(dspi->irq, dspi);
1695 out_ctlr_put:
1696 	spi_controller_put(ctlr);
1697 
1698 	return ret;
1699 }
1700 
1701 static void dspi_remove(struct platform_device *pdev)
1702 {
1703 	struct fsl_dspi *dspi = platform_get_drvdata(pdev);
1704 
1705 	/* Disconnect from the SPI framework */
1706 	spi_unregister_controller(dspi->ctlr);
1707 
1708 	/* Disable RX and TX */
1709 	regmap_update_bits(dspi->regmap, SPI_MCR,
1710 			   SPI_MCR_DIS_TXF | SPI_MCR_DIS_RXF,
1711 			   SPI_MCR_DIS_TXF | SPI_MCR_DIS_RXF);
1712 
1713 	/* Stop Running */
1714 	regmap_update_bits(dspi->regmap, SPI_MCR, SPI_MCR_HALT, SPI_MCR_HALT);
1715 
1716 	dspi_release_dma(dspi);
1717 	if (dspi->irq)
1718 		free_irq(dspi->irq, dspi);
1719 }
1720 
1721 static void dspi_shutdown(struct platform_device *pdev)
1722 {
1723 	dspi_remove(pdev);
1724 }
1725 
1726 static struct platform_driver fsl_dspi_driver = {
1727 	.driver.name		= DRIVER_NAME,
1728 	.driver.of_match_table	= fsl_dspi_dt_ids,
1729 	.driver.pm		= &dspi_pm,
1730 	.probe			= dspi_probe,
1731 	.remove			= dspi_remove,
1732 	.shutdown		= dspi_shutdown,
1733 };
1734 module_platform_driver(fsl_dspi_driver);
1735 
1736 MODULE_DESCRIPTION("Freescale DSPI Controller Driver");
1737 MODULE_LICENSE("GPL");
1738 MODULE_ALIAS("platform:" DRIVER_NAME);
1739