xref: /linux/drivers/spi/spi-fsl-dspi.c (revision 0262163136de813894cb172aa8ccf762b92e5fd7)
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 
336 struct fsl_dspi {
337 	struct spi_controller			*ctlr;
338 	struct platform_device			*pdev;
339 
340 	struct regmap				*regmap;
341 	struct regmap				*regmap_pushr;
342 	int					irq;
343 	struct clk				*clk;
344 
345 	struct spi_transfer			*cur_transfer;
346 	struct spi_message			*cur_msg;
347 	struct chip_data			*cur_chip;
348 	size_t					progress;
349 	size_t					len;
350 	const void				*tx;
351 	void					*rx;
352 	u16					tx_cmd;
353 	bool					mtf_enabled;
354 	const struct fsl_dspi_devtype_data	*devtype_data;
355 
356 	struct completion			xfer_done;
357 
358 	struct fsl_dspi_dma			*dma;
359 
360 	int					oper_word_size;
361 	int					oper_bits_per_word;
362 
363 	int					words_in_flight;
364 
365 	/*
366 	 * Offsets for CMD and TXDATA within SPI_PUSHR when accessed
367 	 * individually (in XSPI mode)
368 	 */
369 	int					pushr_cmd;
370 	int					pushr_tx;
371 
372 	void (*host_to_dev)(struct fsl_dspi *dspi, u32 *txdata);
373 	void (*dev_to_host)(struct fsl_dspi *dspi, u32 rxdata);
374 };
375 
is_s32g_dspi(struct fsl_dspi * data)376 static bool is_s32g_dspi(struct fsl_dspi *data)
377 {
378 	return data->devtype_data == &devtype_data[S32G] ||
379 	       data->devtype_data == &devtype_data[S32G_TARGET];
380 }
381 
dspi_native_host_to_dev(struct fsl_dspi * dspi,u32 * txdata)382 static void dspi_native_host_to_dev(struct fsl_dspi *dspi, u32 *txdata)
383 {
384 	switch (dspi->oper_word_size) {
385 	case 1:
386 		*txdata = *(u8 *)dspi->tx;
387 		break;
388 	case 2:
389 		*txdata = *(u16 *)dspi->tx;
390 		break;
391 	case 4:
392 		*txdata = *(u32 *)dspi->tx;
393 		break;
394 	}
395 	dspi->tx += dspi->oper_word_size;
396 }
397 
dspi_native_dev_to_host(struct fsl_dspi * dspi,u32 rxdata)398 static void dspi_native_dev_to_host(struct fsl_dspi *dspi, u32 rxdata)
399 {
400 	switch (dspi->oper_word_size) {
401 	case 1:
402 		*(u8 *)dspi->rx = rxdata;
403 		break;
404 	case 2:
405 		*(u16 *)dspi->rx = rxdata;
406 		break;
407 	case 4:
408 		*(u32 *)dspi->rx = rxdata;
409 		break;
410 	}
411 	dspi->rx += dspi->oper_word_size;
412 }
413 
dspi_8on32_host_to_dev(struct fsl_dspi * dspi,u32 * txdata)414 static void dspi_8on32_host_to_dev(struct fsl_dspi *dspi, u32 *txdata)
415 {
416 	*txdata = (__force u32)cpu_to_be32(*(u32 *)dspi->tx);
417 	dspi->tx += sizeof(u32);
418 }
419 
dspi_8on32_dev_to_host(struct fsl_dspi * dspi,u32 rxdata)420 static void dspi_8on32_dev_to_host(struct fsl_dspi *dspi, u32 rxdata)
421 {
422 	*(u32 *)dspi->rx = be32_to_cpu((__force __be32)rxdata);
423 	dspi->rx += sizeof(u32);
424 }
425 
dspi_8on16_host_to_dev(struct fsl_dspi * dspi,u32 * txdata)426 static void dspi_8on16_host_to_dev(struct fsl_dspi *dspi, u32 *txdata)
427 {
428 	*txdata = (__force u32)cpu_to_be16(*(u16 *)dspi->tx);
429 	dspi->tx += sizeof(u16);
430 }
431 
dspi_8on16_dev_to_host(struct fsl_dspi * dspi,u32 rxdata)432 static void dspi_8on16_dev_to_host(struct fsl_dspi *dspi, u32 rxdata)
433 {
434 	*(u16 *)dspi->rx = be16_to_cpu((__force __be16)rxdata);
435 	dspi->rx += sizeof(u16);
436 }
437 
dspi_16on32_host_to_dev(struct fsl_dspi * dspi,u32 * txdata)438 static void dspi_16on32_host_to_dev(struct fsl_dspi *dspi, u32 *txdata)
439 {
440 	u16 hi = *(u16 *)dspi->tx;
441 	u16 lo = *(u16 *)(dspi->tx + 2);
442 
443 	*txdata = (u32)hi << 16 | lo;
444 	dspi->tx += sizeof(u32);
445 }
446 
dspi_16on32_dev_to_host(struct fsl_dspi * dspi,u32 rxdata)447 static void dspi_16on32_dev_to_host(struct fsl_dspi *dspi, u32 rxdata)
448 {
449 	u16 hi = rxdata & 0xffff;
450 	u16 lo = rxdata >> 16;
451 
452 	*(u16 *)dspi->rx = lo;
453 	*(u16 *)(dspi->rx + 2) = hi;
454 	dspi->rx += sizeof(u32);
455 }
456 
457 /*
458  * Pop one word from the TX buffer for pushing into the
459  * PUSHR register (TX FIFO)
460  */
dspi_pop_tx(struct fsl_dspi * dspi)461 static u32 dspi_pop_tx(struct fsl_dspi *dspi)
462 {
463 	u32 txdata = 0;
464 
465 	if (dspi->tx)
466 		dspi->host_to_dev(dspi, &txdata);
467 	dspi->len -= dspi->oper_word_size;
468 	return txdata;
469 }
470 
471 /* Prepare one TX FIFO entry (txdata plus cmd) */
dspi_pop_tx_pushr(struct fsl_dspi * dspi)472 static u32 dspi_pop_tx_pushr(struct fsl_dspi *dspi)
473 {
474 	u16 cmd = dspi->tx_cmd, data = dspi_pop_tx(dspi);
475 
476 	if (spi_controller_is_target(dspi->ctlr))
477 		return data;
478 
479 	if (dspi->len > 0)
480 		cmd |= SPI_PUSHR_CMD_CONT;
481 	return cmd << 16 | data;
482 }
483 
484 /* Push one word to the RX buffer from the POPR register (RX FIFO) */
dspi_push_rx(struct fsl_dspi * dspi,u32 rxdata)485 static void dspi_push_rx(struct fsl_dspi *dspi, u32 rxdata)
486 {
487 	if (!dspi->rx)
488 		return;
489 	dspi->dev_to_host(dspi, rxdata);
490 }
491 
dspi_tx_dma_callback(void * arg)492 static void dspi_tx_dma_callback(void *arg)
493 {
494 	struct fsl_dspi *dspi = arg;
495 	struct fsl_dspi_dma *dma = dspi->dma;
496 
497 	complete(&dma->cmd_tx_complete);
498 }
499 
dspi_rx_dma_callback(void * arg)500 static void dspi_rx_dma_callback(void *arg)
501 {
502 	struct fsl_dspi *dspi = arg;
503 	struct fsl_dspi_dma *dma = dspi->dma;
504 	int i;
505 
506 	if (dspi->rx) {
507 		for (i = 0; i < dspi->words_in_flight; i++)
508 			dspi_push_rx(dspi, dspi->dma->rx_dma_buf[i]);
509 	}
510 
511 	complete(&dma->cmd_rx_complete);
512 }
513 
dspi_next_xfer_dma_submit(struct fsl_dspi * dspi)514 static int dspi_next_xfer_dma_submit(struct fsl_dspi *dspi)
515 {
516 	struct device *dev = &dspi->pdev->dev;
517 	struct fsl_dspi_dma *dma = dspi->dma;
518 	int time_left;
519 	int i;
520 
521 	for (i = 0; i < dspi->words_in_flight; i++)
522 		dspi->dma->tx_dma_buf[i] = dspi_pop_tx_pushr(dspi);
523 
524 	dma->tx_desc = dmaengine_prep_slave_single(dma->chan_tx,
525 					dma->tx_dma_phys,
526 					dspi->words_in_flight *
527 					DMA_SLAVE_BUSWIDTH_4_BYTES,
528 					DMA_MEM_TO_DEV,
529 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
530 	if (!dma->tx_desc) {
531 		dev_err(dev, "Not able to get desc for DMA xfer\n");
532 		return -EIO;
533 	}
534 
535 	dma->tx_desc->callback = dspi_tx_dma_callback;
536 	dma->tx_desc->callback_param = dspi;
537 	if (dma_submit_error(dmaengine_submit(dma->tx_desc))) {
538 		dev_err(dev, "DMA submit failed\n");
539 		return -EINVAL;
540 	}
541 
542 	dma->rx_desc = dmaengine_prep_slave_single(dma->chan_rx,
543 					dma->rx_dma_phys,
544 					dspi->words_in_flight *
545 					DMA_SLAVE_BUSWIDTH_4_BYTES,
546 					DMA_DEV_TO_MEM,
547 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
548 	if (!dma->rx_desc) {
549 		dev_err(dev, "Not able to get desc for DMA xfer\n");
550 		return -EIO;
551 	}
552 
553 	dma->rx_desc->callback = dspi_rx_dma_callback;
554 	dma->rx_desc->callback_param = dspi;
555 	if (dma_submit_error(dmaengine_submit(dma->rx_desc))) {
556 		dev_err(dev, "DMA submit failed\n");
557 		return -EINVAL;
558 	}
559 
560 	reinit_completion(&dspi->dma->cmd_rx_complete);
561 	reinit_completion(&dspi->dma->cmd_tx_complete);
562 
563 	dma_async_issue_pending(dma->chan_rx);
564 	dma_async_issue_pending(dma->chan_tx);
565 
566 	if (spi_controller_is_target(dspi->ctlr)) {
567 		wait_for_completion_interruptible(&dspi->dma->cmd_rx_complete);
568 		return 0;
569 	}
570 
571 	time_left = wait_for_completion_timeout(&dspi->dma->cmd_tx_complete,
572 						DMA_COMPLETION_TIMEOUT);
573 	if (time_left == 0) {
574 		dev_err(dev, "DMA tx timeout\n");
575 		dmaengine_terminate_all(dma->chan_tx);
576 		dmaengine_terminate_all(dma->chan_rx);
577 		return -ETIMEDOUT;
578 	}
579 
580 	time_left = wait_for_completion_timeout(&dspi->dma->cmd_rx_complete,
581 						DMA_COMPLETION_TIMEOUT);
582 	if (time_left == 0) {
583 		dev_err(dev, "DMA rx timeout\n");
584 		dmaengine_terminate_all(dma->chan_tx);
585 		dmaengine_terminate_all(dma->chan_rx);
586 		return -ETIMEDOUT;
587 	}
588 
589 	return 0;
590 }
591 
592 static void dspi_setup_accel(struct fsl_dspi *dspi);
593 
dspi_dma_xfer(struct fsl_dspi * dspi)594 static int dspi_dma_xfer(struct fsl_dspi *dspi)
595 {
596 	struct spi_message *message = dspi->cur_msg;
597 	struct device *dev = &dspi->pdev->dev;
598 	int ret = 0;
599 
600 	/*
601 	 * dspi->len gets decremented by dspi_pop_tx_pushr in
602 	 * dspi_next_xfer_dma_submit
603 	 */
604 	while (dspi->len) {
605 		/* Figure out operational bits-per-word for this chunk */
606 		dspi_setup_accel(dspi);
607 
608 		dspi->words_in_flight = dspi->len / dspi->oper_word_size;
609 		if (dspi->words_in_flight > dspi->devtype_data->fifo_size)
610 			dspi->words_in_flight = dspi->devtype_data->fifo_size;
611 
612 		message->actual_length += dspi->words_in_flight *
613 					  dspi->oper_word_size;
614 
615 		ret = dspi_next_xfer_dma_submit(dspi);
616 		if (ret) {
617 			dev_err(dev, "DMA transfer failed\n");
618 			break;
619 		}
620 	}
621 
622 	return ret;
623 }
624 
dspi_request_dma(struct fsl_dspi * dspi,phys_addr_t phy_addr)625 static int dspi_request_dma(struct fsl_dspi *dspi, phys_addr_t phy_addr)
626 {
627 	int dma_bufsize = dspi->devtype_data->fifo_size * 2;
628 	struct device *dev = &dspi->pdev->dev;
629 	struct dma_slave_config cfg;
630 	struct fsl_dspi_dma *dma;
631 	int ret;
632 
633 	dma = devm_kzalloc(dev, sizeof(*dma), GFP_KERNEL);
634 	if (!dma)
635 		return -ENOMEM;
636 
637 	dma->chan_rx = dma_request_chan(dev, "rx");
638 	if (IS_ERR(dma->chan_rx))
639 		return dev_err_probe(dev, PTR_ERR(dma->chan_rx), "rx dma channel not available\n");
640 
641 	dma->chan_tx = dma_request_chan(dev, "tx");
642 	if (IS_ERR(dma->chan_tx)) {
643 		ret = dev_err_probe(dev, PTR_ERR(dma->chan_tx), "tx dma channel not available\n");
644 		goto err_tx_channel;
645 	}
646 
647 	dma->tx_dma_buf = dma_alloc_coherent(dma->chan_tx->device->dev,
648 					     dma_bufsize, &dma->tx_dma_phys,
649 					     GFP_KERNEL);
650 	if (!dma->tx_dma_buf) {
651 		ret = -ENOMEM;
652 		goto err_tx_dma_buf;
653 	}
654 
655 	dma->rx_dma_buf = dma_alloc_coherent(dma->chan_rx->device->dev,
656 					     dma_bufsize, &dma->rx_dma_phys,
657 					     GFP_KERNEL);
658 	if (!dma->rx_dma_buf) {
659 		ret = -ENOMEM;
660 		goto err_rx_dma_buf;
661 	}
662 
663 	memset(&cfg, 0, sizeof(cfg));
664 	cfg.src_addr = phy_addr + SPI_POPR;
665 	cfg.dst_addr = phy_addr + SPI_PUSHR;
666 	cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
667 	cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
668 	cfg.src_maxburst = 1;
669 	cfg.dst_maxburst = 1;
670 
671 	cfg.direction = DMA_DEV_TO_MEM;
672 	ret = dmaengine_slave_config(dma->chan_rx, &cfg);
673 	if (ret) {
674 		dev_err_probe(dev, ret, "can't configure rx dma channel\n");
675 		goto err_slave_config;
676 	}
677 
678 	cfg.direction = DMA_MEM_TO_DEV;
679 	ret = dmaengine_slave_config(dma->chan_tx, &cfg);
680 	if (ret) {
681 		dev_err_probe(dev, ret, "can't configure tx dma channel\n");
682 		goto err_slave_config;
683 	}
684 
685 	dspi->dma = dma;
686 	init_completion(&dma->cmd_tx_complete);
687 	init_completion(&dma->cmd_rx_complete);
688 
689 	return 0;
690 
691 err_slave_config:
692 	dma_free_coherent(dma->chan_rx->device->dev,
693 			  dma_bufsize, dma->rx_dma_buf, dma->rx_dma_phys);
694 err_rx_dma_buf:
695 	dma_free_coherent(dma->chan_tx->device->dev,
696 			  dma_bufsize, dma->tx_dma_buf, dma->tx_dma_phys);
697 err_tx_dma_buf:
698 	dma_release_channel(dma->chan_tx);
699 err_tx_channel:
700 	dma_release_channel(dma->chan_rx);
701 
702 	devm_kfree(dev, dma);
703 	dspi->dma = NULL;
704 
705 	return ret;
706 }
707 
dspi_release_dma(struct fsl_dspi * dspi)708 static void dspi_release_dma(struct fsl_dspi *dspi)
709 {
710 	int dma_bufsize = dspi->devtype_data->fifo_size * 2;
711 	struct fsl_dspi_dma *dma = dspi->dma;
712 
713 	if (!dma)
714 		return;
715 
716 	if (dma->chan_tx) {
717 		dma_free_coherent(dma->chan_tx->device->dev, dma_bufsize,
718 				  dma->tx_dma_buf, dma->tx_dma_phys);
719 		dma_release_channel(dma->chan_tx);
720 	}
721 
722 	if (dma->chan_rx) {
723 		dma_free_coherent(dma->chan_rx->device->dev, dma_bufsize,
724 				  dma->rx_dma_buf, dma->rx_dma_phys);
725 		dma_release_channel(dma->chan_rx);
726 	}
727 }
728 
hz_to_spi_baud(char * pbr,char * br,int speed_hz,unsigned long clkrate,bool mtf_enabled)729 static void hz_to_spi_baud(char *pbr, char *br, int speed_hz,
730 			   unsigned long clkrate, bool mtf_enabled)
731 {
732 	/* Valid baud rate pre-scaler values */
733 	int pbr_tbl[4] = {2, 3, 5, 7};
734 	int brs[16] = {	2,	4,	6,	8,
735 			16,	32,	64,	128,
736 			256,	512,	1024,	2048,
737 			4096,	8192,	16384,	32768 };
738 	int scale_needed, scale, minscale = INT_MAX;
739 	int i, j;
740 
741 	scale_needed = clkrate / speed_hz;
742 	if (clkrate % speed_hz)
743 		scale_needed++;
744 
745 	for (i = 0; i < ARRAY_SIZE(brs); i++)
746 		for (j = 0; j < ARRAY_SIZE(pbr_tbl); j++) {
747 			if (mtf_enabled) {
748 				/* In MTF mode DBR=1 so frequency is doubled */
749 				scale = (brs[i] * pbr_tbl[j]) / 2;
750 			} else {
751 				scale = brs[i] * pbr_tbl[j];
752 			}
753 
754 			if (scale >= scale_needed) {
755 				if (scale < minscale) {
756 					minscale = scale;
757 					*br = i;
758 					*pbr = j;
759 				}
760 				break;
761 			}
762 		}
763 
764 	if (minscale == INT_MAX) {
765 		pr_warn("Can not find valid baud rate,speed_hz is %d,clkrate is %ld, we use the max prescaler value.\n",
766 			speed_hz, clkrate);
767 		*pbr = ARRAY_SIZE(pbr_tbl) - 1;
768 		*br =  ARRAY_SIZE(brs) - 1;
769 	}
770 }
771 
ns_delay_scale(char * psc,char * sc,int delay_ns,unsigned long clkrate)772 static void ns_delay_scale(char *psc, char *sc, int delay_ns,
773 			   unsigned long clkrate)
774 {
775 	int scale_needed, scale, minscale = INT_MAX;
776 	int pscale_tbl[4] = {1, 3, 5, 7};
777 	u32 remainder;
778 	int i, j;
779 
780 	scale_needed = div_u64_rem((u64)delay_ns * clkrate, NSEC_PER_SEC,
781 				   &remainder);
782 	if (remainder)
783 		scale_needed++;
784 
785 	for (i = 0; i < ARRAY_SIZE(pscale_tbl); i++)
786 		for (j = 0; j <= SPI_CTAR_SCALE_BITS; j++) {
787 			scale = pscale_tbl[i] * (2 << j);
788 			if (scale >= scale_needed) {
789 				if (scale < minscale) {
790 					minscale = scale;
791 					*psc = i;
792 					*sc = j;
793 				}
794 				break;
795 			}
796 		}
797 
798 	if (minscale == INT_MAX) {
799 		pr_warn("Cannot find correct scale values for %dns delay at clkrate %ld, using max prescaler value",
800 			delay_ns, clkrate);
801 		*psc = ARRAY_SIZE(pscale_tbl) - 1;
802 		*sc = SPI_CTAR_SCALE_BITS;
803 	}
804 }
805 
dspi_pushr_cmd_write(struct fsl_dspi * dspi,u16 cmd)806 static void dspi_pushr_cmd_write(struct fsl_dspi *dspi, u16 cmd)
807 {
808 	/*
809 	 * The only time when the PCS doesn't need continuation after this word
810 	 * is when it's last. We need to look ahead, because we actually call
811 	 * dspi_pop_tx (the function that decrements dspi->len) _after_
812 	 * dspi_pushr_cmd_write with XSPI mode. As for how much in advance? One
813 	 * word is enough. If there's more to transmit than that,
814 	 * dspi_xspi_write will know to split the FIFO writes in 2, and
815 	 * generate a new PUSHR command with the final word that will have PCS
816 	 * deasserted (not continued) here.
817 	 */
818 	if (dspi->len > dspi->oper_word_size)
819 		cmd |= SPI_PUSHR_CMD_CONT;
820 	regmap_write(dspi->regmap_pushr, dspi->pushr_cmd, cmd);
821 }
822 
dspi_pushr_txdata_write(struct fsl_dspi * dspi,u16 txdata)823 static void dspi_pushr_txdata_write(struct fsl_dspi *dspi, u16 txdata)
824 {
825 	regmap_write(dspi->regmap_pushr, dspi->pushr_tx, txdata);
826 }
827 
dspi_xspi_fifo_write(struct fsl_dspi * dspi,int num_words)828 static void dspi_xspi_fifo_write(struct fsl_dspi *dspi, int num_words)
829 {
830 	int num_bytes = num_words * dspi->oper_word_size;
831 	u16 tx_cmd = dspi->tx_cmd;
832 
833 	/*
834 	 * If the PCS needs to de-assert (i.e. we're at the end of the buffer
835 	 * and cs_change does not want the PCS to stay on), then we need a new
836 	 * PUSHR command, since this one (for the body of the buffer)
837 	 * necessarily has the CONT bit set.
838 	 * So send one word less during this go, to force a split and a command
839 	 * with a single word next time, when CONT will be unset.
840 	 */
841 	if (!(dspi->tx_cmd & SPI_PUSHR_CMD_CONT) && num_bytes == dspi->len)
842 		tx_cmd |= SPI_PUSHR_CMD_EOQ;
843 
844 	/* Update CTARE */
845 	regmap_write(dspi->regmap, SPI_CTARE(0),
846 		     SPI_FRAME_EBITS(dspi->oper_bits_per_word) |
847 		     SPI_CTARE_DTCP(num_words));
848 
849 	/*
850 	 * Write the CMD FIFO entry first, and then the two
851 	 * corresponding TX FIFO entries (or one...).
852 	 */
853 	dspi_pushr_cmd_write(dspi, tx_cmd);
854 
855 	/* Fill TX FIFO with as many transfers as possible */
856 	while (num_words--) {
857 		u32 data = dspi_pop_tx(dspi);
858 
859 		dspi_pushr_txdata_write(dspi, data & 0xFFFF);
860 		if (dspi->oper_bits_per_word > 16)
861 			dspi_pushr_txdata_write(dspi, data >> 16);
862 	}
863 }
864 
dspi_popr_read(struct fsl_dspi * dspi)865 static u32 dspi_popr_read(struct fsl_dspi *dspi)
866 {
867 	u32 rxdata = 0;
868 
869 	regmap_read(dspi->regmap, SPI_POPR, &rxdata);
870 	return rxdata;
871 }
872 
dspi_fifo_read(struct fsl_dspi * dspi)873 static void dspi_fifo_read(struct fsl_dspi *dspi)
874 {
875 	int num_fifo_entries = dspi->words_in_flight;
876 
877 	/* Read one FIFO entry and push to rx buffer */
878 	while (num_fifo_entries--)
879 		dspi_push_rx(dspi, dspi_popr_read(dspi));
880 }
881 
dspi_setup_accel(struct fsl_dspi * dspi)882 static void dspi_setup_accel(struct fsl_dspi *dspi)
883 {
884 	struct spi_transfer *xfer = dspi->cur_transfer;
885 	bool odd = !!(dspi->len & 1);
886 
887 	/*
888 	 * No accel for DMA transfers or frames not multiples of 8 bits at the
889 	 * moment.
890 	 */
891 	if (dspi->devtype_data->trans_mode == DSPI_DMA_MODE ||
892 	    xfer->bits_per_word % 8)
893 		goto no_accel;
894 
895 	if (!odd && dspi->len <= dspi->devtype_data->fifo_size * 2) {
896 		dspi->oper_bits_per_word = 16;
897 	} else if (odd && dspi->len <= dspi->devtype_data->fifo_size) {
898 		dspi->oper_bits_per_word = 8;
899 	} else {
900 		/* Start off with maximum supported by hardware */
901 		dspi->oper_bits_per_word = 32;
902 
903 		/*
904 		 * And go down only if the buffer can't be sent with
905 		 * words this big
906 		 */
907 		do {
908 			if (dspi->len >= DIV_ROUND_UP(dspi->oper_bits_per_word, 8))
909 				break;
910 
911 			dspi->oper_bits_per_word /= 2;
912 		} while (dspi->oper_bits_per_word > 8);
913 	}
914 
915 	if (xfer->bits_per_word == 8 && dspi->oper_bits_per_word == 32) {
916 		dspi->dev_to_host = dspi_8on32_dev_to_host;
917 		dspi->host_to_dev = dspi_8on32_host_to_dev;
918 	} else if (xfer->bits_per_word == 8 && dspi->oper_bits_per_word == 16) {
919 		dspi->dev_to_host = dspi_8on16_dev_to_host;
920 		dspi->host_to_dev = dspi_8on16_host_to_dev;
921 	} else if (xfer->bits_per_word == 16 && dspi->oper_bits_per_word == 32) {
922 		dspi->dev_to_host = dspi_16on32_dev_to_host;
923 		dspi->host_to_dev = dspi_16on32_host_to_dev;
924 	} else {
925 no_accel:
926 		dspi->dev_to_host = dspi_native_dev_to_host;
927 		dspi->host_to_dev = dspi_native_host_to_dev;
928 		dspi->oper_bits_per_word = xfer->bits_per_word;
929 	}
930 
931 	dspi->oper_word_size = DIV_ROUND_UP(dspi->oper_bits_per_word, 8);
932 
933 	/*
934 	 * Update CTAR here (code is common for XSPI and DMA modes).
935 	 * We will update CTARE in the portion specific to XSPI, when we
936 	 * also know the preload value (DTCP).
937 	 */
938 	regmap_write(dspi->regmap, SPI_CTAR(0),
939 		     dspi->cur_chip->ctar_val |
940 		     SPI_FRAME_BITS(dspi->oper_bits_per_word));
941 }
942 
dspi_fifo_write(struct fsl_dspi * dspi)943 static void dspi_fifo_write(struct fsl_dspi *dspi)
944 {
945 	int num_fifo_entries = dspi->devtype_data->fifo_size;
946 	struct spi_transfer *xfer = dspi->cur_transfer;
947 	struct spi_message *msg = dspi->cur_msg;
948 	int num_words, num_bytes;
949 
950 	dspi_setup_accel(dspi);
951 
952 	/* In XSPI mode each 32-bit word occupies 2 TX FIFO entries */
953 	if (dspi->oper_word_size == 4)
954 		num_fifo_entries /= 2;
955 
956 	/*
957 	 * Integer division intentionally trims off odd (or non-multiple of 4)
958 	 * numbers of bytes at the end of the buffer, which will be sent next
959 	 * time using a smaller oper_word_size.
960 	 */
961 	num_words = dspi->len / dspi->oper_word_size;
962 	if (num_words > num_fifo_entries)
963 		num_words = num_fifo_entries;
964 
965 	/* Update total number of bytes that were transferred */
966 	num_bytes = num_words * dspi->oper_word_size;
967 	msg->actual_length += num_bytes;
968 	dspi->progress += num_bytes / DIV_ROUND_UP(xfer->bits_per_word, 8);
969 
970 	/*
971 	 * Update shared variable for use in the next interrupt (both in
972 	 * dspi_fifo_read and in dspi_fifo_write).
973 	 */
974 	dspi->words_in_flight = num_words;
975 
976 	spi_take_timestamp_pre(dspi->ctlr, xfer, dspi->progress, !dspi->irq);
977 
978 	dspi_xspi_fifo_write(dspi, num_words);
979 	/*
980 	 * Everything after this point is in a potential race with the next
981 	 * interrupt, so we must never use dspi->words_in_flight again since it
982 	 * might already be modified by the next dspi_fifo_write.
983 	 */
984 
985 	spi_take_timestamp_post(dspi->ctlr, dspi->cur_transfer,
986 				dspi->progress, !dspi->irq);
987 }
988 
dspi_rxtx(struct fsl_dspi * dspi)989 static int dspi_rxtx(struct fsl_dspi *dspi)
990 {
991 	dspi_fifo_read(dspi);
992 
993 	if (!dspi->len)
994 		/* Success! */
995 		return 0;
996 
997 	dspi_fifo_write(dspi);
998 
999 	return -EINPROGRESS;
1000 }
1001 
dspi_poll(struct fsl_dspi * dspi)1002 static int dspi_poll(struct fsl_dspi *dspi)
1003 {
1004 	int tries = 1000;
1005 	u32 spi_sr;
1006 
1007 	do {
1008 		regmap_read(dspi->regmap, SPI_SR, &spi_sr);
1009 		regmap_write(dspi->regmap, SPI_SR, spi_sr);
1010 
1011 		if (spi_sr & SPI_SR_CMDTCF)
1012 			break;
1013 	} while (--tries);
1014 
1015 	if (!tries)
1016 		return -ETIMEDOUT;
1017 
1018 	return dspi_rxtx(dspi);
1019 }
1020 
dspi_interrupt(int irq,void * dev_id)1021 static irqreturn_t dspi_interrupt(int irq, void *dev_id)
1022 {
1023 	struct fsl_dspi *dspi = (struct fsl_dspi *)dev_id;
1024 	u32 spi_sr;
1025 
1026 	regmap_read(dspi->regmap, SPI_SR, &spi_sr);
1027 	regmap_write(dspi->regmap, SPI_SR, spi_sr);
1028 
1029 	if (!(spi_sr & SPI_SR_CMDTCF))
1030 		return IRQ_NONE;
1031 
1032 	if (dspi_rxtx(dspi) == 0)
1033 		complete(&dspi->xfer_done);
1034 
1035 	return IRQ_HANDLED;
1036 }
1037 
dspi_assert_cs(struct spi_device * spi,bool * cs)1038 static void dspi_assert_cs(struct spi_device *spi, bool *cs)
1039 {
1040 	if (!spi_get_csgpiod(spi, 0) || *cs)
1041 		return;
1042 
1043 	gpiod_set_value_cansleep(spi_get_csgpiod(spi, 0), true);
1044 	*cs = true;
1045 }
1046 
dspi_deassert_cs(struct spi_device * spi,bool * cs)1047 static void dspi_deassert_cs(struct spi_device *spi, bool *cs)
1048 {
1049 	if (!spi_get_csgpiod(spi, 0) || !*cs)
1050 		return;
1051 
1052 	gpiod_set_value_cansleep(spi_get_csgpiod(spi, 0), false);
1053 	*cs = false;
1054 }
1055 
dspi_transfer_one_message(struct spi_controller * ctlr,struct spi_message * message)1056 static int dspi_transfer_one_message(struct spi_controller *ctlr,
1057 				     struct spi_message *message)
1058 {
1059 	struct fsl_dspi *dspi = spi_controller_get_devdata(ctlr);
1060 	struct spi_device *spi = message->spi;
1061 	struct spi_transfer *transfer;
1062 	bool cs = false;
1063 	int status = 0;
1064 	u32 val = 0;
1065 	bool cs_change = false;
1066 
1067 	message->actual_length = 0;
1068 
1069 	/* Put DSPI in running mode if halted. */
1070 	regmap_read(dspi->regmap, SPI_MCR, &val);
1071 	if (val & SPI_MCR_HALT) {
1072 		regmap_update_bits(dspi->regmap, SPI_MCR, SPI_MCR_HALT, 0);
1073 		while (regmap_read(dspi->regmap, SPI_SR, &val) >= 0 &&
1074 		       !(val & SPI_SR_TXRXS))
1075 			;
1076 	}
1077 
1078 	list_for_each_entry(transfer, &message->transfers, transfer_list) {
1079 		dspi->cur_transfer = transfer;
1080 		dspi->cur_msg = message;
1081 		dspi->cur_chip = spi_get_ctldata(spi);
1082 
1083 		dspi_assert_cs(spi, &cs);
1084 
1085 		/* Prepare command word for CMD FIFO */
1086 		dspi->tx_cmd = SPI_PUSHR_CMD_CTAS(0);
1087 		if (!spi_get_csgpiod(spi, 0))
1088 			dspi->tx_cmd |= SPI_PUSHR_CMD_PCS(spi_get_chipselect(spi, 0));
1089 
1090 		if (list_is_last(&dspi->cur_transfer->transfer_list,
1091 				 &dspi->cur_msg->transfers)) {
1092 			/* Leave PCS activated after last transfer when
1093 			 * cs_change is set.
1094 			 */
1095 			if (transfer->cs_change)
1096 				dspi->tx_cmd |= SPI_PUSHR_CMD_CONT;
1097 		} else {
1098 			/* Keep PCS active between transfers in same message
1099 			 * when cs_change is not set, and de-activate PCS
1100 			 * between transfers in the same message when
1101 			 * cs_change is set.
1102 			 */
1103 			if (!transfer->cs_change)
1104 				dspi->tx_cmd |= SPI_PUSHR_CMD_CONT;
1105 		}
1106 
1107 		cs_change = transfer->cs_change;
1108 		dspi->tx = transfer->tx_buf;
1109 		dspi->rx = transfer->rx_buf;
1110 		dspi->len = transfer->len;
1111 		dspi->progress = 0;
1112 
1113 		regmap_update_bits(dspi->regmap, SPI_MCR,
1114 				   SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF,
1115 				   SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF);
1116 
1117 		regmap_write(dspi->regmap, SPI_SR, SPI_SR_CLEAR);
1118 
1119 		spi_take_timestamp_pre(dspi->ctlr, dspi->cur_transfer,
1120 				       dspi->progress, !dspi->irq);
1121 
1122 		if (dspi->devtype_data->trans_mode == DSPI_DMA_MODE) {
1123 			status = dspi_dma_xfer(dspi);
1124 		} else {
1125 			/*
1126 			 * Reinitialize the completion before transferring data
1127 			 * to avoid the case where it might remain in the done
1128 			 * state due to a spurious interrupt from a previous
1129 			 * transfer. This could falsely signal that the current
1130 			 * transfer has completed.
1131 			 */
1132 			if (dspi->irq)
1133 				reinit_completion(&dspi->xfer_done);
1134 
1135 			dspi_fifo_write(dspi);
1136 
1137 			if (dspi->irq) {
1138 				wait_for_completion(&dspi->xfer_done);
1139 			} else {
1140 				do {
1141 					status = dspi_poll(dspi);
1142 				} while (status == -EINPROGRESS);
1143 			}
1144 		}
1145 		if (status)
1146 			break;
1147 
1148 		spi_transfer_delay_exec(transfer);
1149 
1150 		if (!(dspi->tx_cmd & SPI_PUSHR_CMD_CONT))
1151 			dspi_deassert_cs(spi, &cs);
1152 	}
1153 
1154 	if (status || !cs_change) {
1155 		/* Put DSPI in stop mode */
1156 		regmap_update_bits(dspi->regmap, SPI_MCR,
1157 				   SPI_MCR_HALT, SPI_MCR_HALT);
1158 		while (regmap_read(dspi->regmap, SPI_SR, &val) >= 0 &&
1159 		       val & SPI_SR_TXRXS)
1160 			;
1161 	}
1162 
1163 	message->status = status;
1164 	spi_finalize_current_message(ctlr);
1165 
1166 	return status;
1167 }
1168 
dspi_set_mtf(struct fsl_dspi * dspi)1169 static int dspi_set_mtf(struct fsl_dspi *dspi)
1170 {
1171 	if (spi_controller_is_target(dspi->ctlr))
1172 		return 0;
1173 
1174 	if (dspi->mtf_enabled)
1175 		regmap_update_bits(dspi->regmap, SPI_MCR, SPI_MCR_MTFE,
1176 				   SPI_MCR_MTFE);
1177 	else
1178 		regmap_update_bits(dspi->regmap, SPI_MCR, SPI_MCR_MTFE, 0);
1179 
1180 	return 0;
1181 }
1182 
dspi_setup(struct spi_device * spi)1183 static int dspi_setup(struct spi_device *spi)
1184 {
1185 	struct fsl_dspi *dspi = spi_controller_get_devdata(spi->controller);
1186 	u32 period_ns = DIV_ROUND_UP(NSEC_PER_SEC, spi->max_speed_hz);
1187 	unsigned char br = 0, pbr = 0, pcssck = 0, cssck = 0;
1188 	u32 quarter_period_ns = DIV_ROUND_UP(period_ns, 4);
1189 	u32 cs_sck_delay = 0, sck_cs_delay = 0;
1190 	struct fsl_dspi_platform_data *pdata;
1191 	unsigned char pasc = 0, asc = 0;
1192 	struct gpio_desc *gpio_cs;
1193 	struct chip_data *chip;
1194 	unsigned long clkrate;
1195 	bool cs = true;
1196 	int val;
1197 
1198 	/* Only alloc on first setup */
1199 	chip = spi_get_ctldata(spi);
1200 	if (chip == NULL) {
1201 		chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
1202 		if (!chip)
1203 			return -ENOMEM;
1204 	}
1205 
1206 	pdata = dev_get_platdata(&dspi->pdev->dev);
1207 
1208 	if (!pdata) {
1209 		val = spi_delay_to_ns(&spi->cs_setup, NULL);
1210 		cs_sck_delay = val >= 0 ? val : 0;
1211 		if (!cs_sck_delay)
1212 			of_property_read_u32(spi->dev.of_node,
1213 					     "fsl,spi-cs-sck-delay",
1214 					     &cs_sck_delay);
1215 
1216 		val = spi_delay_to_ns(&spi->cs_hold, NULL);
1217 		sck_cs_delay =  val >= 0 ? val : 0;
1218 		if (!sck_cs_delay)
1219 			of_property_read_u32(spi->dev.of_node,
1220 					     "fsl,spi-sck-cs-delay",
1221 					     &sck_cs_delay);
1222 	} else {
1223 		cs_sck_delay = pdata->cs_sck_delay;
1224 		sck_cs_delay = pdata->sck_cs_delay;
1225 	}
1226 
1227 	/* Since tCSC and tASC apply to continuous transfers too, avoid SCK
1228 	 * glitches of half a cycle by never allowing tCSC + tASC to go below
1229 	 * half a SCK period.
1230 	 */
1231 	if (cs_sck_delay < quarter_period_ns)
1232 		cs_sck_delay = quarter_period_ns;
1233 	if (sck_cs_delay < quarter_period_ns)
1234 		sck_cs_delay = quarter_period_ns;
1235 
1236 	dev_dbg(&spi->dev,
1237 		"DSPI controller timing params: CS-to-SCK delay %u ns, SCK-to-CS delay %u ns\n",
1238 		cs_sck_delay, sck_cs_delay);
1239 
1240 	clkrate = clk_get_rate(dspi->clk);
1241 
1242 	if (is_s32g_dspi(dspi) && spi->max_speed_hz > SPI_25MHZ)
1243 		dspi->mtf_enabled = true;
1244 	else
1245 		dspi->mtf_enabled = false;
1246 
1247 	dspi_set_mtf(dspi);
1248 
1249 	hz_to_spi_baud(&pbr, &br, spi->max_speed_hz, clkrate,
1250 		       dspi->mtf_enabled);
1251 
1252 	/* Set PCS to SCK delay scale values */
1253 	ns_delay_scale(&pcssck, &cssck, cs_sck_delay, clkrate);
1254 
1255 	/* Set After SCK delay scale values */
1256 	ns_delay_scale(&pasc, &asc, sck_cs_delay, clkrate);
1257 
1258 	chip->ctar_val = 0;
1259 	if (spi->mode & SPI_CPOL)
1260 		chip->ctar_val |= SPI_CTAR_CPOL;
1261 	if (spi->mode & SPI_CPHA)
1262 		chip->ctar_val |= SPI_CTAR_CPHA;
1263 
1264 	if (!spi_controller_is_target(dspi->ctlr)) {
1265 		chip->ctar_val |= SPI_CTAR_PCSSCK(pcssck) |
1266 				  SPI_CTAR_CSSCK(cssck) |
1267 				  SPI_CTAR_PASC(pasc) |
1268 				  SPI_CTAR_ASC(asc) |
1269 				  SPI_CTAR_PBR(pbr) |
1270 				  SPI_CTAR_BR(br);
1271 
1272 		if (dspi->mtf_enabled)
1273 			chip->ctar_val |= SPI_CTAR_DBR;
1274 
1275 		if (spi->mode & SPI_LSB_FIRST)
1276 			chip->ctar_val |= SPI_CTAR_LSBFE;
1277 	}
1278 
1279 	gpio_cs = spi_get_csgpiod(spi, 0);
1280 	if (gpio_cs)
1281 		gpiod_direction_output(gpio_cs, false);
1282 
1283 	dspi_deassert_cs(spi, &cs);
1284 
1285 	spi_set_ctldata(spi, chip);
1286 
1287 	return 0;
1288 }
1289 
dspi_cleanup(struct spi_device * spi)1290 static void dspi_cleanup(struct spi_device *spi)
1291 {
1292 	struct chip_data *chip = spi_get_ctldata(spi);
1293 
1294 	dev_dbg(&spi->dev, "spi_device %u.%u cleanup\n",
1295 		spi->controller->bus_num, spi_get_chipselect(spi, 0));
1296 
1297 	kfree(chip);
1298 }
1299 
1300 static const struct of_device_id fsl_dspi_dt_ids[] = {
1301 	{
1302 		.compatible = "fsl,vf610-dspi",
1303 		.data = &devtype_data[VF610],
1304 	}, {
1305 		.compatible = "fsl,ls1021a-v1.0-dspi",
1306 		.data = &devtype_data[LS1021A],
1307 	}, {
1308 		.compatible = "fsl,ls1012a-dspi",
1309 		.data = &devtype_data[LS1012A],
1310 	}, {
1311 		.compatible = "fsl,ls1028a-dspi",
1312 		.data = &devtype_data[LS1028A],
1313 	}, {
1314 		.compatible = "fsl,ls1043a-dspi",
1315 		.data = &devtype_data[LS1043A],
1316 	}, {
1317 		.compatible = "fsl,ls1046a-dspi",
1318 		.data = &devtype_data[LS1046A],
1319 	}, {
1320 		.compatible = "fsl,ls2080a-dspi",
1321 		.data = &devtype_data[LS2080A],
1322 	}, {
1323 		.compatible = "fsl,ls2085a-dspi",
1324 		.data = &devtype_data[LS2085A],
1325 	}, {
1326 		.compatible = "fsl,lx2160a-dspi",
1327 		.data = &devtype_data[LX2160A],
1328 	}, {
1329 		.compatible = "nxp,s32g2-dspi",
1330 		.data = &devtype_data[S32G],
1331 	},
1332 	{ /* sentinel */ }
1333 };
1334 MODULE_DEVICE_TABLE(of, fsl_dspi_dt_ids);
1335 
dspi_init(struct fsl_dspi * dspi)1336 static int dspi_init(struct fsl_dspi *dspi)
1337 {
1338 	unsigned int mcr;
1339 
1340 	/* Set idle states for all chip select signals to high */
1341 	mcr = SPI_MCR_PCSIS(GENMASK(dspi->ctlr->max_native_cs - 1, 0));
1342 
1343 	if (dspi->devtype_data->trans_mode == DSPI_XSPI_MODE)
1344 		mcr |= SPI_MCR_XSPI;
1345 	if (!spi_controller_is_target(dspi->ctlr))
1346 		mcr |= SPI_MCR_HOST;
1347 
1348 	mcr |= SPI_MCR_HALT;
1349 
1350 	regmap_write(dspi->regmap, SPI_MCR, mcr);
1351 	regmap_write(dspi->regmap, SPI_SR, SPI_SR_CLEAR);
1352 
1353 	switch (dspi->devtype_data->trans_mode) {
1354 	case DSPI_XSPI_MODE:
1355 		regmap_write(dspi->regmap, SPI_RSER, SPI_RSER_CMDTCFE);
1356 		break;
1357 	case DSPI_DMA_MODE:
1358 		regmap_write(dspi->regmap, SPI_RSER,
1359 			     SPI_RSER_TFFFE | SPI_RSER_TFFFD |
1360 			     SPI_RSER_RFDFE | SPI_RSER_RFDFD);
1361 		break;
1362 	default:
1363 		dev_err(&dspi->pdev->dev, "unsupported trans_mode %u\n",
1364 			dspi->devtype_data->trans_mode);
1365 		return -EINVAL;
1366 	}
1367 
1368 	return 0;
1369 }
1370 
1371 #ifdef CONFIG_PM_SLEEP
dspi_suspend(struct device * dev)1372 static int dspi_suspend(struct device *dev)
1373 {
1374 	struct fsl_dspi *dspi = dev_get_drvdata(dev);
1375 
1376 	if (dspi->irq)
1377 		disable_irq(dspi->irq);
1378 	spi_controller_suspend(dspi->ctlr);
1379 	clk_disable_unprepare(dspi->clk);
1380 
1381 	pinctrl_pm_select_sleep_state(dev);
1382 
1383 	return 0;
1384 }
1385 
dspi_resume(struct device * dev)1386 static int dspi_resume(struct device *dev)
1387 {
1388 	struct fsl_dspi *dspi = dev_get_drvdata(dev);
1389 	int ret;
1390 
1391 	pinctrl_pm_select_default_state(dev);
1392 
1393 	ret = clk_prepare_enable(dspi->clk);
1394 	if (ret)
1395 		return ret;
1396 	spi_controller_resume(dspi->ctlr);
1397 
1398 	ret = dspi_init(dspi);
1399 	if (ret) {
1400 		dev_err(dev, "failed to initialize dspi during resume\n");
1401 		return ret;
1402 	}
1403 
1404 	dspi_set_mtf(dspi);
1405 
1406 	if (dspi->irq)
1407 		enable_irq(dspi->irq);
1408 
1409 	return 0;
1410 }
1411 #endif /* CONFIG_PM_SLEEP */
1412 
1413 static SIMPLE_DEV_PM_OPS(dspi_pm, dspi_suspend, dspi_resume);
1414 
dspi_target_abort(struct spi_controller * host)1415 static int dspi_target_abort(struct spi_controller *host)
1416 {
1417 	struct fsl_dspi *dspi = spi_controller_get_devdata(host);
1418 
1419 	/*
1420 	 * Terminate all pending DMA transactions for the SPI working
1421 	 * in TARGET mode.
1422 	 */
1423 	if (dspi->devtype_data->trans_mode == DSPI_DMA_MODE) {
1424 		dmaengine_terminate_sync(dspi->dma->chan_rx);
1425 		dmaengine_terminate_sync(dspi->dma->chan_tx);
1426 	}
1427 
1428 	/* Clear the internal DSPI RX and TX FIFO buffers */
1429 	regmap_update_bits(dspi->regmap, SPI_MCR,
1430 			   SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF,
1431 			   SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF);
1432 
1433 	return 0;
1434 }
1435 
dspi_probe(struct platform_device * pdev)1436 static int dspi_probe(struct platform_device *pdev)
1437 {
1438 	struct device_node *np = pdev->dev.of_node;
1439 	struct fsl_dspi_platform_data *pdata;
1440 	struct spi_controller *ctlr;
1441 	int ret, cs_num, bus_num = -1;
1442 	struct fsl_dspi *dspi;
1443 	struct resource *res;
1444 	void __iomem *base;
1445 	bool big_endian;
1446 
1447 	dspi = devm_kzalloc(&pdev->dev, sizeof(*dspi), GFP_KERNEL);
1448 	if (!dspi)
1449 		return -ENOMEM;
1450 
1451 	if (of_property_read_bool(np, "spi-slave"))
1452 		ctlr = spi_alloc_target(&pdev->dev, 0);
1453 	else
1454 		ctlr = spi_alloc_host(&pdev->dev, 0);
1455 	if (!ctlr)
1456 		return -ENOMEM;
1457 
1458 	spi_controller_set_devdata(ctlr, dspi);
1459 	platform_set_drvdata(pdev, dspi);
1460 
1461 	dspi->pdev = pdev;
1462 	dspi->ctlr = ctlr;
1463 
1464 	ctlr->setup = dspi_setup;
1465 	ctlr->transfer_one_message = dspi_transfer_one_message;
1466 	ctlr->dev.of_node = pdev->dev.of_node;
1467 
1468 	ctlr->cleanup = dspi_cleanup;
1469 	ctlr->target_abort = dspi_target_abort;
1470 	ctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;
1471 	ctlr->use_gpio_descriptors = true;
1472 
1473 	pdata = dev_get_platdata(&pdev->dev);
1474 	if (pdata) {
1475 		ctlr->num_chipselect = ctlr->max_native_cs = pdata->cs_num;
1476 		ctlr->bus_num = pdata->bus_num;
1477 
1478 		/* Only Coldfire uses platform data */
1479 		dspi->devtype_data = &devtype_data[MCF5441X];
1480 		big_endian = true;
1481 	} else {
1482 
1483 		ret = of_property_read_u32(np, "spi-num-chipselects", &cs_num);
1484 		if (ret < 0) {
1485 			dev_err(&pdev->dev, "can't get spi-num-chipselects\n");
1486 			goto out_ctlr_put;
1487 		}
1488 		ctlr->num_chipselect = ctlr->max_native_cs = cs_num;
1489 
1490 		of_property_read_u32(np, "bus-num", &bus_num);
1491 		ctlr->bus_num = bus_num;
1492 
1493 		dspi->devtype_data = of_device_get_match_data(&pdev->dev);
1494 		if (!dspi->devtype_data) {
1495 			dev_err(&pdev->dev, "can't get devtype_data\n");
1496 			ret = -EFAULT;
1497 			goto out_ctlr_put;
1498 		}
1499 
1500 		big_endian = of_device_is_big_endian(np);
1501 	}
1502 	if (big_endian) {
1503 		dspi->pushr_cmd = 0;
1504 		dspi->pushr_tx = 2;
1505 	} else {
1506 		dspi->pushr_cmd = 2;
1507 		dspi->pushr_tx = 0;
1508 	}
1509 
1510 	if (spi_controller_is_target(ctlr) && is_s32g_dspi(dspi))
1511 		dspi->devtype_data = &devtype_data[S32G_TARGET];
1512 
1513 	if (dspi->devtype_data->trans_mode == DSPI_XSPI_MODE)
1514 		ctlr->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1515 	else
1516 		ctlr->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16);
1517 
1518 	base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
1519 	if (IS_ERR(base)) {
1520 		ret = PTR_ERR(base);
1521 		goto out_ctlr_put;
1522 	}
1523 
1524 	dspi->regmap = devm_regmap_init_mmio(&pdev->dev, base,
1525 					     dspi->devtype_data->regmap);
1526 	if (IS_ERR(dspi->regmap)) {
1527 		dev_err(&pdev->dev, "failed to init regmap: %ld\n",
1528 				PTR_ERR(dspi->regmap));
1529 		ret = PTR_ERR(dspi->regmap);
1530 		goto out_ctlr_put;
1531 	}
1532 
1533 	if (dspi->devtype_data->trans_mode == DSPI_XSPI_MODE) {
1534 		dspi->regmap_pushr = devm_regmap_init_mmio(
1535 			&pdev->dev, base + SPI_PUSHR,
1536 			&dspi_regmap_config[DSPI_PUSHR]);
1537 		if (IS_ERR(dspi->regmap_pushr)) {
1538 			dev_err(&pdev->dev,
1539 				"failed to init pushr regmap: %ld\n",
1540 				PTR_ERR(dspi->regmap_pushr));
1541 			ret = PTR_ERR(dspi->regmap_pushr);
1542 			goto out_ctlr_put;
1543 		}
1544 	}
1545 
1546 	dspi->clk = devm_clk_get_enabled(&pdev->dev, "dspi");
1547 	if (IS_ERR(dspi->clk)) {
1548 		ret = PTR_ERR(dspi->clk);
1549 		dev_err(&pdev->dev, "unable to get clock\n");
1550 		goto out_ctlr_put;
1551 	}
1552 
1553 	ret = dspi_init(dspi);
1554 	if (ret)
1555 		goto out_ctlr_put;
1556 
1557 	dspi->irq = platform_get_irq(pdev, 0);
1558 	if (dspi->irq <= 0) {
1559 		dev_info(&pdev->dev,
1560 			 "can't get platform irq, using poll mode\n");
1561 		dspi->irq = 0;
1562 		goto poll_mode;
1563 	}
1564 
1565 	init_completion(&dspi->xfer_done);
1566 
1567 	ret = request_threaded_irq(dspi->irq, dspi_interrupt, NULL,
1568 				   IRQF_SHARED, pdev->name, dspi);
1569 	if (ret < 0) {
1570 		dev_err(&pdev->dev, "Unable to attach DSPI interrupt\n");
1571 		goto out_ctlr_put;
1572 	}
1573 
1574 poll_mode:
1575 
1576 	if (dspi->devtype_data->trans_mode == DSPI_DMA_MODE) {
1577 		ret = dspi_request_dma(dspi, res->start);
1578 		if (ret < 0) {
1579 			dev_err(&pdev->dev, "can't get dma channels\n");
1580 			goto out_free_irq;
1581 		}
1582 	}
1583 
1584 	ctlr->max_speed_hz =
1585 		clk_get_rate(dspi->clk) / dspi->devtype_data->max_clock_factor;
1586 
1587 	if (dspi->devtype_data->trans_mode != DSPI_DMA_MODE)
1588 		ctlr->ptp_sts_supported = true;
1589 
1590 	ret = spi_register_controller(ctlr);
1591 	if (ret != 0) {
1592 		dev_err(&pdev->dev, "Problem registering DSPI ctlr\n");
1593 		goto out_release_dma;
1594 	}
1595 
1596 	return ret;
1597 
1598 out_release_dma:
1599 	dspi_release_dma(dspi);
1600 out_free_irq:
1601 	if (dspi->irq)
1602 		free_irq(dspi->irq, dspi);
1603 out_ctlr_put:
1604 	spi_controller_put(ctlr);
1605 
1606 	return ret;
1607 }
1608 
dspi_remove(struct platform_device * pdev)1609 static void dspi_remove(struct platform_device *pdev)
1610 {
1611 	struct fsl_dspi *dspi = platform_get_drvdata(pdev);
1612 
1613 	/* Disconnect from the SPI framework */
1614 	spi_unregister_controller(dspi->ctlr);
1615 
1616 	/* Disable RX and TX */
1617 	regmap_update_bits(dspi->regmap, SPI_MCR,
1618 			   SPI_MCR_DIS_TXF | SPI_MCR_DIS_RXF,
1619 			   SPI_MCR_DIS_TXF | SPI_MCR_DIS_RXF);
1620 
1621 	/* Stop Running */
1622 	regmap_update_bits(dspi->regmap, SPI_MCR, SPI_MCR_HALT, SPI_MCR_HALT);
1623 
1624 	dspi_release_dma(dspi);
1625 	if (dspi->irq)
1626 		free_irq(dspi->irq, dspi);
1627 }
1628 
dspi_shutdown(struct platform_device * pdev)1629 static void dspi_shutdown(struct platform_device *pdev)
1630 {
1631 	dspi_remove(pdev);
1632 }
1633 
1634 static struct platform_driver fsl_dspi_driver = {
1635 	.driver.name		= DRIVER_NAME,
1636 	.driver.of_match_table	= fsl_dspi_dt_ids,
1637 	.driver.pm		= &dspi_pm,
1638 	.probe			= dspi_probe,
1639 	.remove			= dspi_remove,
1640 	.shutdown		= dspi_shutdown,
1641 };
1642 module_platform_driver(fsl_dspi_driver);
1643 
1644 MODULE_DESCRIPTION("Freescale DSPI Controller Driver");
1645 MODULE_LICENSE("GPL");
1646 MODULE_ALIAS("platform:" DRIVER_NAME);
1647