xref: /openbmc/linux/drivers/spi/spi-fsl-dspi.c (revision abe916c5) 
1 // SPDX-License-Identifier: GPL-2.0+
2 //
3 // Copyright 2013 Freescale Semiconductor, Inc.
4 // Copyright 2020 NXP
5 //
6 // Freescale DSPI driver
7 // This file contains a driver for the Freescale DSPI
8 
9 #include <linux/clk.h>
10 #include <linux/delay.h>
11 #include <linux/dmaengine.h>
12 #include <linux/dma-mapping.h>
13 #include <linux/interrupt.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/of_device.h>
17 #include <linux/pinctrl/consumer.h>
18 #include <linux/regmap.h>
19 #include <linux/spi/spi.h>
20 #include <linux/spi/spi-fsl-dspi.h>
21 
22 #define DRIVER_NAME			"fsl-dspi"
23 
24 #define SPI_MCR				0x00
25 #define SPI_MCR_MASTER			BIT(31)
26 #define SPI_MCR_PCSIS(x)		((x) << 16)
27 #define SPI_MCR_CLR_TXF			BIT(11)
28 #define SPI_MCR_CLR_RXF			BIT(10)
29 #define SPI_MCR_XSPI			BIT(3)
30 #define SPI_MCR_DIS_TXF			BIT(13)
31 #define SPI_MCR_DIS_RXF			BIT(12)
32 #define SPI_MCR_HALT			BIT(0)
33 
34 #define SPI_TCR				0x08
35 #define SPI_TCR_GET_TCNT(x)		(((x) & GENMASK(31, 16)) >> 16)
36 
37 #define SPI_CTAR(x)			(0x0c + (((x) & GENMASK(1, 0)) * 4))
38 #define SPI_CTAR_FMSZ(x)		(((x) << 27) & GENMASK(30, 27))
39 #define SPI_CTAR_CPOL			BIT(26)
40 #define SPI_CTAR_CPHA			BIT(25)
41 #define SPI_CTAR_LSBFE			BIT(24)
42 #define SPI_CTAR_PCSSCK(x)		(((x) << 22) & GENMASK(23, 22))
43 #define SPI_CTAR_PASC(x)		(((x) << 20) & GENMASK(21, 20))
44 #define SPI_CTAR_PDT(x)			(((x) << 18) & GENMASK(19, 18))
45 #define SPI_CTAR_PBR(x)			(((x) << 16) & GENMASK(17, 16))
46 #define SPI_CTAR_CSSCK(x)		(((x) << 12) & GENMASK(15, 12))
47 #define SPI_CTAR_ASC(x)			(((x) << 8) & GENMASK(11, 8))
48 #define SPI_CTAR_DT(x)			(((x) << 4) & GENMASK(7, 4))
49 #define SPI_CTAR_BR(x)			((x) & GENMASK(3, 0))
50 #define SPI_CTAR_SCALE_BITS		0xf
51 
52 #define SPI_CTAR0_SLAVE			0x0c
53 
54 #define SPI_SR				0x2c
55 #define SPI_SR_TCFQF			BIT(31)
56 #define SPI_SR_TFUF			BIT(27)
57 #define SPI_SR_TFFF			BIT(25)
58 #define SPI_SR_CMDTCF			BIT(23)
59 #define SPI_SR_SPEF			BIT(21)
60 #define SPI_SR_RFOF			BIT(19)
61 #define SPI_SR_TFIWF			BIT(18)
62 #define SPI_SR_RFDF			BIT(17)
63 #define SPI_SR_CMDFFF			BIT(16)
64 #define SPI_SR_CLEAR			(SPI_SR_TCFQF | \
65 					SPI_SR_TFUF | SPI_SR_TFFF | \
66 					SPI_SR_CMDTCF | SPI_SR_SPEF | \
67 					SPI_SR_RFOF | SPI_SR_TFIWF | \
68 					SPI_SR_RFDF | SPI_SR_CMDFFF)
69 
70 #define SPI_RSER_TFFFE			BIT(25)
71 #define SPI_RSER_TFFFD			BIT(24)
72 #define SPI_RSER_RFDFE			BIT(17)
73 #define SPI_RSER_RFDFD			BIT(16)
74 
75 #define SPI_RSER			0x30
76 #define SPI_RSER_TCFQE			BIT(31)
77 #define SPI_RSER_CMDTCFE		BIT(23)
78 
79 #define SPI_PUSHR			0x34
80 #define SPI_PUSHR_CMD_CONT		BIT(15)
81 #define SPI_PUSHR_CMD_CTAS(x)		(((x) << 12 & GENMASK(14, 12)))
82 #define SPI_PUSHR_CMD_EOQ		BIT(11)
83 #define SPI_PUSHR_CMD_CTCNT		BIT(10)
84 #define SPI_PUSHR_CMD_PCS(x)		(BIT(x) & GENMASK(5, 0))
85 
86 #define SPI_PUSHR_SLAVE			0x34
87 
88 #define SPI_POPR			0x38
89 
90 #define SPI_TXFR0			0x3c
91 #define SPI_TXFR1			0x40
92 #define SPI_TXFR2			0x44
93 #define SPI_TXFR3			0x48
94 #define SPI_RXFR0			0x7c
95 #define SPI_RXFR1			0x80
96 #define SPI_RXFR2			0x84
97 #define SPI_RXFR3			0x88
98 
99 #define SPI_CTARE(x)			(0x11c + (((x) & GENMASK(1, 0)) * 4))
100 #define SPI_CTARE_FMSZE(x)		(((x) & 0x1) << 16)
101 #define SPI_CTARE_DTCP(x)		((x) & 0x7ff)
102 
103 #define SPI_SREX			0x13c
104 
105 #define SPI_FRAME_BITS(bits)		SPI_CTAR_FMSZ((bits) - 1)
106 #define SPI_FRAME_EBITS(bits)		SPI_CTARE_FMSZE(((bits) - 1) >> 4)
107 
108 #define DMA_COMPLETION_TIMEOUT		msecs_to_jiffies(3000)
109 
110 struct chip_data {
111 	u32			ctar_val;
112 };
113 
114 enum dspi_trans_mode {
115 	DSPI_XSPI_MODE,
116 	DSPI_DMA_MODE,
117 };
118 
119 struct fsl_dspi_devtype_data {
120 	enum dspi_trans_mode	trans_mode;
121 	u8			max_clock_factor;
122 	int			fifo_size;
123 };
124 
125 enum {
126 	LS1021A,
127 	LS1012A,
128 	LS1028A,
129 	LS1043A,
130 	LS1046A,
131 	LS2080A,
132 	LS2085A,
133 	LX2160A,
134 	MCF5441X,
135 	VF610,
136 };
137 
138 static const struct fsl_dspi_devtype_data devtype_data[] = {
139 	[VF610] = {
140 		.trans_mode		= DSPI_DMA_MODE,
141 		.max_clock_factor	= 2,
142 		.fifo_size		= 4,
143 	},
144 	[LS1021A] = {
145 		/* Has A-011218 DMA erratum */
146 		.trans_mode		= DSPI_XSPI_MODE,
147 		.max_clock_factor	= 8,
148 		.fifo_size		= 4,
149 	},
150 	[LS1012A] = {
151 		/* Has A-011218 DMA erratum */
152 		.trans_mode		= DSPI_XSPI_MODE,
153 		.max_clock_factor	= 8,
154 		.fifo_size		= 16,
155 	},
156 	[LS1028A] = {
157 		.trans_mode		= DSPI_XSPI_MODE,
158 		.max_clock_factor	= 8,
159 		.fifo_size		= 4,
160 	},
161 	[LS1043A] = {
162 		/* Has A-011218 DMA erratum */
163 		.trans_mode		= DSPI_XSPI_MODE,
164 		.max_clock_factor	= 8,
165 		.fifo_size		= 16,
166 	},
167 	[LS1046A] = {
168 		/* Has A-011218 DMA erratum */
169 		.trans_mode		= DSPI_XSPI_MODE,
170 		.max_clock_factor	= 8,
171 		.fifo_size		= 16,
172 	},
173 	[LS2080A] = {
174 		.trans_mode		= DSPI_XSPI_MODE,
175 		.max_clock_factor	= 8,
176 		.fifo_size		= 4,
177 	},
178 	[LS2085A] = {
179 		.trans_mode		= DSPI_XSPI_MODE,
180 		.max_clock_factor	= 8,
181 		.fifo_size		= 4,
182 	},
183 	[LX2160A] = {
184 		.trans_mode		= DSPI_XSPI_MODE,
185 		.max_clock_factor	= 8,
186 		.fifo_size		= 4,
187 	},
188 	[MCF5441X] = {
189 		.trans_mode		= DSPI_DMA_MODE,
190 		.max_clock_factor	= 8,
191 		.fifo_size		= 16,
192 	},
193 };
194 
195 struct fsl_dspi_dma {
196 	u32					*tx_dma_buf;
197 	struct dma_chan				*chan_tx;
198 	dma_addr_t				tx_dma_phys;
199 	struct completion			cmd_tx_complete;
200 	struct dma_async_tx_descriptor		*tx_desc;
201 
202 	u32					*rx_dma_buf;
203 	struct dma_chan				*chan_rx;
204 	dma_addr_t				rx_dma_phys;
205 	struct completion			cmd_rx_complete;
206 	struct dma_async_tx_descriptor		*rx_desc;
207 };
208 
209 struct fsl_dspi {
210 	struct spi_controller			*ctlr;
211 	struct platform_device			*pdev;
212 
213 	struct regmap				*regmap;
214 	struct regmap				*regmap_pushr;
215 	int					irq;
216 	struct clk				*clk;
217 
218 	struct spi_transfer			*cur_transfer;
219 	struct spi_message			*cur_msg;
220 	struct chip_data			*cur_chip;
221 	size_t					progress;
222 	size_t					len;
223 	const void				*tx;
224 	void					*rx;
225 	u16					tx_cmd;
226 	const struct fsl_dspi_devtype_data	*devtype_data;
227 
228 	struct completion			xfer_done;
229 
230 	struct fsl_dspi_dma			*dma;
231 
232 	int					oper_word_size;
233 	int					oper_bits_per_word;
234 
235 	int					words_in_flight;
236 
237 	/*
238 	 * Offsets for CMD and TXDATA within SPI_PUSHR when accessed
239 	 * individually (in XSPI mode)
240 	 */
241 	int					pushr_cmd;
242 	int					pushr_tx;
243 
244 	void (*host_to_dev)(struct fsl_dspi *dspi, u32 *txdata);
245 	void (*dev_to_host)(struct fsl_dspi *dspi, u32 rxdata);
246 };
247 
248 static void dspi_native_host_to_dev(struct fsl_dspi *dspi, u32 *txdata)
249 {
250 	switch (dspi->oper_word_size) {
251 	case 1:
252 		*txdata = *(u8 *)dspi->tx;
253 		break;
254 	case 2:
255 		*txdata = *(u16 *)dspi->tx;
256 		break;
257 	case 4:
258 		*txdata = *(u32 *)dspi->tx;
259 		break;
260 	}
261 	dspi->tx += dspi->oper_word_size;
262 }
263 
264 static void dspi_native_dev_to_host(struct fsl_dspi *dspi, u32 rxdata)
265 {
266 	switch (dspi->oper_word_size) {
267 	case 1:
268 		*(u8 *)dspi->rx = rxdata;
269 		break;
270 	case 2:
271 		*(u16 *)dspi->rx = rxdata;
272 		break;
273 	case 4:
274 		*(u32 *)dspi->rx = rxdata;
275 		break;
276 	}
277 	dspi->rx += dspi->oper_word_size;
278 }
279 
280 static void dspi_8on32_host_to_dev(struct fsl_dspi *dspi, u32 *txdata)
281 {
282 	*txdata = cpu_to_be32(*(u32 *)dspi->tx);
283 	dspi->tx += sizeof(u32);
284 }
285 
286 static void dspi_8on32_dev_to_host(struct fsl_dspi *dspi, u32 rxdata)
287 {
288 	*(u32 *)dspi->rx = be32_to_cpu(rxdata);
289 	dspi->rx += sizeof(u32);
290 }
291 
292 static void dspi_8on16_host_to_dev(struct fsl_dspi *dspi, u32 *txdata)
293 {
294 	*txdata = cpu_to_be16(*(u16 *)dspi->tx);
295 	dspi->tx += sizeof(u16);
296 }
297 
298 static void dspi_8on16_dev_to_host(struct fsl_dspi *dspi, u32 rxdata)
299 {
300 	*(u16 *)dspi->rx = be16_to_cpu(rxdata);
301 	dspi->rx += sizeof(u16);
302 }
303 
304 static void dspi_16on32_host_to_dev(struct fsl_dspi *dspi, u32 *txdata)
305 {
306 	u16 hi = *(u16 *)dspi->tx;
307 	u16 lo = *(u16 *)(dspi->tx + 2);
308 
309 	*txdata = (u32)hi << 16 | lo;
310 	dspi->tx += sizeof(u32);
311 }
312 
313 static void dspi_16on32_dev_to_host(struct fsl_dspi *dspi, u32 rxdata)
314 {
315 	u16 hi = rxdata & 0xffff;
316 	u16 lo = rxdata >> 16;
317 
318 	*(u16 *)dspi->rx = lo;
319 	*(u16 *)(dspi->rx + 2) = hi;
320 	dspi->rx += sizeof(u32);
321 }
322 
323 /*
324  * Pop one word from the TX buffer for pushing into the
325  * PUSHR register (TX FIFO)
326  */
327 static u32 dspi_pop_tx(struct fsl_dspi *dspi)
328 {
329 	u32 txdata = 0;
330 
331 	if (dspi->tx)
332 		dspi->host_to_dev(dspi, &txdata);
333 	dspi->len -= dspi->oper_word_size;
334 	return txdata;
335 }
336 
337 /* Prepare one TX FIFO entry (txdata plus cmd) */
338 static u32 dspi_pop_tx_pushr(struct fsl_dspi *dspi)
339 {
340 	u16 cmd = dspi->tx_cmd, data = dspi_pop_tx(dspi);
341 
342 	if (spi_controller_is_slave(dspi->ctlr))
343 		return data;
344 
345 	if (dspi->len > 0)
346 		cmd |= SPI_PUSHR_CMD_CONT;
347 	return cmd << 16 | data;
348 }
349 
350 /* Push one word to the RX buffer from the POPR register (RX FIFO) */
351 static void dspi_push_rx(struct fsl_dspi *dspi, u32 rxdata)
352 {
353 	if (!dspi->rx)
354 		return;
355 	dspi->dev_to_host(dspi, rxdata);
356 }
357 
358 static void dspi_tx_dma_callback(void *arg)
359 {
360 	struct fsl_dspi *dspi = arg;
361 	struct fsl_dspi_dma *dma = dspi->dma;
362 
363 	complete(&dma->cmd_tx_complete);
364 }
365 
366 static void dspi_rx_dma_callback(void *arg)
367 {
368 	struct fsl_dspi *dspi = arg;
369 	struct fsl_dspi_dma *dma = dspi->dma;
370 	int i;
371 
372 	if (dspi->rx) {
373 		for (i = 0; i < dspi->words_in_flight; i++)
374 			dspi_push_rx(dspi, dspi->dma->rx_dma_buf[i]);
375 	}
376 
377 	complete(&dma->cmd_rx_complete);
378 }
379 
380 static int dspi_next_xfer_dma_submit(struct fsl_dspi *dspi)
381 {
382 	struct device *dev = &dspi->pdev->dev;
383 	struct fsl_dspi_dma *dma = dspi->dma;
384 	int time_left;
385 	int i;
386 
387 	for (i = 0; i < dspi->words_in_flight; i++)
388 		dspi->dma->tx_dma_buf[i] = dspi_pop_tx_pushr(dspi);
389 
390 	dma->tx_desc = dmaengine_prep_slave_single(dma->chan_tx,
391 					dma->tx_dma_phys,
392 					dspi->words_in_flight *
393 					DMA_SLAVE_BUSWIDTH_4_BYTES,
394 					DMA_MEM_TO_DEV,
395 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
396 	if (!dma->tx_desc) {
397 		dev_err(dev, "Not able to get desc for DMA xfer\n");
398 		return -EIO;
399 	}
400 
401 	dma->tx_desc->callback = dspi_tx_dma_callback;
402 	dma->tx_desc->callback_param = dspi;
403 	if (dma_submit_error(dmaengine_submit(dma->tx_desc))) {
404 		dev_err(dev, "DMA submit failed\n");
405 		return -EINVAL;
406 	}
407 
408 	dma->rx_desc = dmaengine_prep_slave_single(dma->chan_rx,
409 					dma->rx_dma_phys,
410 					dspi->words_in_flight *
411 					DMA_SLAVE_BUSWIDTH_4_BYTES,
412 					DMA_DEV_TO_MEM,
413 					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
414 	if (!dma->rx_desc) {
415 		dev_err(dev, "Not able to get desc for DMA xfer\n");
416 		return -EIO;
417 	}
418 
419 	dma->rx_desc->callback = dspi_rx_dma_callback;
420 	dma->rx_desc->callback_param = dspi;
421 	if (dma_submit_error(dmaengine_submit(dma->rx_desc))) {
422 		dev_err(dev, "DMA submit failed\n");
423 		return -EINVAL;
424 	}
425 
426 	reinit_completion(&dspi->dma->cmd_rx_complete);
427 	reinit_completion(&dspi->dma->cmd_tx_complete);
428 
429 	dma_async_issue_pending(dma->chan_rx);
430 	dma_async_issue_pending(dma->chan_tx);
431 
432 	if (spi_controller_is_slave(dspi->ctlr)) {
433 		wait_for_completion_interruptible(&dspi->dma->cmd_rx_complete);
434 		return 0;
435 	}
436 
437 	time_left = wait_for_completion_timeout(&dspi->dma->cmd_tx_complete,
438 						DMA_COMPLETION_TIMEOUT);
439 	if (time_left == 0) {
440 		dev_err(dev, "DMA tx timeout\n");
441 		dmaengine_terminate_all(dma->chan_tx);
442 		dmaengine_terminate_all(dma->chan_rx);
443 		return -ETIMEDOUT;
444 	}
445 
446 	time_left = wait_for_completion_timeout(&dspi->dma->cmd_rx_complete,
447 						DMA_COMPLETION_TIMEOUT);
448 	if (time_left == 0) {
449 		dev_err(dev, "DMA rx timeout\n");
450 		dmaengine_terminate_all(dma->chan_tx);
451 		dmaengine_terminate_all(dma->chan_rx);
452 		return -ETIMEDOUT;
453 	}
454 
455 	return 0;
456 }
457 
458 static void dspi_setup_accel(struct fsl_dspi *dspi);
459 
460 static int dspi_dma_xfer(struct fsl_dspi *dspi)
461 {
462 	struct spi_message *message = dspi->cur_msg;
463 	struct device *dev = &dspi->pdev->dev;
464 	int ret = 0;
465 
466 	/*
467 	 * dspi->len gets decremented by dspi_pop_tx_pushr in
468 	 * dspi_next_xfer_dma_submit
469 	 */
470 	while (dspi->len) {
471 		/* Figure out operational bits-per-word for this chunk */
472 		dspi_setup_accel(dspi);
473 
474 		dspi->words_in_flight = dspi->len / dspi->oper_word_size;
475 		if (dspi->words_in_flight > dspi->devtype_data->fifo_size)
476 			dspi->words_in_flight = dspi->devtype_data->fifo_size;
477 
478 		message->actual_length += dspi->words_in_flight *
479 					  dspi->oper_word_size;
480 
481 		ret = dspi_next_xfer_dma_submit(dspi);
482 		if (ret) {
483 			dev_err(dev, "DMA transfer failed\n");
484 			break;
485 		}
486 	}
487 
488 	return ret;
489 }
490 
491 static int dspi_request_dma(struct fsl_dspi *dspi, phys_addr_t phy_addr)
492 {
493 	int dma_bufsize = dspi->devtype_data->fifo_size * 2;
494 	struct device *dev = &dspi->pdev->dev;
495 	struct dma_slave_config cfg;
496 	struct fsl_dspi_dma *dma;
497 	int ret;
498 
499 	dma = devm_kzalloc(dev, sizeof(*dma), GFP_KERNEL);
500 	if (!dma)
501 		return -ENOMEM;
502 
503 	dma->chan_rx = dma_request_chan(dev, "rx");
504 	if (IS_ERR(dma->chan_rx)) {
505 		dev_err(dev, "rx dma channel not available\n");
506 		ret = PTR_ERR(dma->chan_rx);
507 		return ret;
508 	}
509 
510 	dma->chan_tx = dma_request_chan(dev, "tx");
511 	if (IS_ERR(dma->chan_tx)) {
512 		dev_err(dev, "tx dma channel not available\n");
513 		ret = PTR_ERR(dma->chan_tx);
514 		goto err_tx_channel;
515 	}
516 
517 	dma->tx_dma_buf = dma_alloc_coherent(dma->chan_tx->device->dev,
518 					     dma_bufsize, &dma->tx_dma_phys,
519 					     GFP_KERNEL);
520 	if (!dma->tx_dma_buf) {
521 		ret = -ENOMEM;
522 		goto err_tx_dma_buf;
523 	}
524 
525 	dma->rx_dma_buf = dma_alloc_coherent(dma->chan_rx->device->dev,
526 					     dma_bufsize, &dma->rx_dma_phys,
527 					     GFP_KERNEL);
528 	if (!dma->rx_dma_buf) {
529 		ret = -ENOMEM;
530 		goto err_rx_dma_buf;
531 	}
532 
533 	memset(&cfg, 0, sizeof(cfg));
534 	cfg.src_addr = phy_addr + SPI_POPR;
535 	cfg.dst_addr = phy_addr + SPI_PUSHR;
536 	cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
537 	cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
538 	cfg.src_maxburst = 1;
539 	cfg.dst_maxburst = 1;
540 
541 	cfg.direction = DMA_DEV_TO_MEM;
542 	ret = dmaengine_slave_config(dma->chan_rx, &cfg);
543 	if (ret) {
544 		dev_err(dev, "can't configure rx dma channel\n");
545 		ret = -EINVAL;
546 		goto err_slave_config;
547 	}
548 
549 	cfg.direction = DMA_MEM_TO_DEV;
550 	ret = dmaengine_slave_config(dma->chan_tx, &cfg);
551 	if (ret) {
552 		dev_err(dev, "can't configure tx dma channel\n");
553 		ret = -EINVAL;
554 		goto err_slave_config;
555 	}
556 
557 	dspi->dma = dma;
558 	init_completion(&dma->cmd_tx_complete);
559 	init_completion(&dma->cmd_rx_complete);
560 
561 	return 0;
562 
563 err_slave_config:
564 	dma_free_coherent(dma->chan_rx->device->dev,
565 			  dma_bufsize, dma->rx_dma_buf, dma->rx_dma_phys);
566 err_rx_dma_buf:
567 	dma_free_coherent(dma->chan_tx->device->dev,
568 			  dma_bufsize, dma->tx_dma_buf, dma->tx_dma_phys);
569 err_tx_dma_buf:
570 	dma_release_channel(dma->chan_tx);
571 err_tx_channel:
572 	dma_release_channel(dma->chan_rx);
573 
574 	devm_kfree(dev, dma);
575 	dspi->dma = NULL;
576 
577 	return ret;
578 }
579 
580 static void dspi_release_dma(struct fsl_dspi *dspi)
581 {
582 	int dma_bufsize = dspi->devtype_data->fifo_size * 2;
583 	struct fsl_dspi_dma *dma = dspi->dma;
584 
585 	if (!dma)
586 		return;
587 
588 	if (dma->chan_tx) {
589 		dma_free_coherent(dma->chan_tx->device->dev, dma_bufsize,
590 				  dma->tx_dma_buf, dma->tx_dma_phys);
591 		dma_release_channel(dma->chan_tx);
592 	}
593 
594 	if (dma->chan_rx) {
595 		dma_free_coherent(dma->chan_rx->device->dev, dma_bufsize,
596 				  dma->rx_dma_buf, dma->rx_dma_phys);
597 		dma_release_channel(dma->chan_rx);
598 	}
599 }
600 
601 static void hz_to_spi_baud(char *pbr, char *br, int speed_hz,
602 			   unsigned long clkrate)
603 {
604 	/* Valid baud rate pre-scaler values */
605 	int pbr_tbl[4] = {2, 3, 5, 7};
606 	int brs[16] = {	2,	4,	6,	8,
607 			16,	32,	64,	128,
608 			256,	512,	1024,	2048,
609 			4096,	8192,	16384,	32768 };
610 	int scale_needed, scale, minscale = INT_MAX;
611 	int i, j;
612 
613 	scale_needed = clkrate / speed_hz;
614 	if (clkrate % speed_hz)
615 		scale_needed++;
616 
617 	for (i = 0; i < ARRAY_SIZE(brs); i++)
618 		for (j = 0; j < ARRAY_SIZE(pbr_tbl); j++) {
619 			scale = brs[i] * pbr_tbl[j];
620 			if (scale >= scale_needed) {
621 				if (scale < minscale) {
622 					minscale = scale;
623 					*br = i;
624 					*pbr = j;
625 				}
626 				break;
627 			}
628 		}
629 
630 	if (minscale == INT_MAX) {
631 		pr_warn("Can not find valid baud rate,speed_hz is %d,clkrate is %ld, we use the max prescaler value.\n",
632 			speed_hz, clkrate);
633 		*pbr = ARRAY_SIZE(pbr_tbl) - 1;
634 		*br =  ARRAY_SIZE(brs) - 1;
635 	}
636 }
637 
638 static void ns_delay_scale(char *psc, char *sc, int delay_ns,
639 			   unsigned long clkrate)
640 {
641 	int scale_needed, scale, minscale = INT_MAX;
642 	int pscale_tbl[4] = {1, 3, 5, 7};
643 	u32 remainder;
644 	int i, j;
645 
646 	scale_needed = div_u64_rem((u64)delay_ns * clkrate, NSEC_PER_SEC,
647 				   &remainder);
648 	if (remainder)
649 		scale_needed++;
650 
651 	for (i = 0; i < ARRAY_SIZE(pscale_tbl); i++)
652 		for (j = 0; j <= SPI_CTAR_SCALE_BITS; j++) {
653 			scale = pscale_tbl[i] * (2 << j);
654 			if (scale >= scale_needed) {
655 				if (scale < minscale) {
656 					minscale = scale;
657 					*psc = i;
658 					*sc = j;
659 				}
660 				break;
661 			}
662 		}
663 
664 	if (minscale == INT_MAX) {
665 		pr_warn("Cannot find correct scale values for %dns delay at clkrate %ld, using max prescaler value",
666 			delay_ns, clkrate);
667 		*psc = ARRAY_SIZE(pscale_tbl) - 1;
668 		*sc = SPI_CTAR_SCALE_BITS;
669 	}
670 }
671 
672 static void dspi_pushr_cmd_write(struct fsl_dspi *dspi, u16 cmd)
673 {
674 	/*
675 	 * The only time when the PCS doesn't need continuation after this word
676 	 * is when it's last. We need to look ahead, because we actually call
677 	 * dspi_pop_tx (the function that decrements dspi->len) _after_
678 	 * dspi_pushr_cmd_write with XSPI mode. As for how much in advance? One
679 	 * word is enough. If there's more to transmit than that,
680 	 * dspi_xspi_write will know to split the FIFO writes in 2, and
681 	 * generate a new PUSHR command with the final word that will have PCS
682 	 * deasserted (not continued) here.
683 	 */
684 	if (dspi->len > dspi->oper_word_size)
685 		cmd |= SPI_PUSHR_CMD_CONT;
686 	regmap_write(dspi->regmap_pushr, dspi->pushr_cmd, cmd);
687 }
688 
689 static void dspi_pushr_txdata_write(struct fsl_dspi *dspi, u16 txdata)
690 {
691 	regmap_write(dspi->regmap_pushr, dspi->pushr_tx, txdata);
692 }
693 
694 static void dspi_xspi_fifo_write(struct fsl_dspi *dspi, int num_words)
695 {
696 	int num_bytes = num_words * dspi->oper_word_size;
697 	u16 tx_cmd = dspi->tx_cmd;
698 
699 	/*
700 	 * If the PCS needs to de-assert (i.e. we're at the end of the buffer
701 	 * and cs_change does not want the PCS to stay on), then we need a new
702 	 * PUSHR command, since this one (for the body of the buffer)
703 	 * necessarily has the CONT bit set.
704 	 * So send one word less during this go, to force a split and a command
705 	 * with a single word next time, when CONT will be unset.
706 	 */
707 	if (!(dspi->tx_cmd & SPI_PUSHR_CMD_CONT) && num_bytes == dspi->len)
708 		tx_cmd |= SPI_PUSHR_CMD_EOQ;
709 
710 	/* Update CTARE */
711 	regmap_write(dspi->regmap, SPI_CTARE(0),
712 		     SPI_FRAME_EBITS(dspi->oper_bits_per_word) |
713 		     SPI_CTARE_DTCP(num_words));
714 
715 	/*
716 	 * Write the CMD FIFO entry first, and then the two
717 	 * corresponding TX FIFO entries (or one...).
718 	 */
719 	dspi_pushr_cmd_write(dspi, tx_cmd);
720 
721 	/* Fill TX FIFO with as many transfers as possible */
722 	while (num_words--) {
723 		u32 data = dspi_pop_tx(dspi);
724 
725 		dspi_pushr_txdata_write(dspi, data & 0xFFFF);
726 		if (dspi->oper_bits_per_word > 16)
727 			dspi_pushr_txdata_write(dspi, data >> 16);
728 	}
729 }
730 
731 static u32 dspi_popr_read(struct fsl_dspi *dspi)
732 {
733 	u32 rxdata = 0;
734 
735 	regmap_read(dspi->regmap, SPI_POPR, &rxdata);
736 	return rxdata;
737 }
738 
739 static void dspi_fifo_read(struct fsl_dspi *dspi)
740 {
741 	int num_fifo_entries = dspi->words_in_flight;
742 
743 	/* Read one FIFO entry and push to rx buffer */
744 	while (num_fifo_entries--)
745 		dspi_push_rx(dspi, dspi_popr_read(dspi));
746 }
747 
748 static void dspi_setup_accel(struct fsl_dspi *dspi)
749 {
750 	struct spi_transfer *xfer = dspi->cur_transfer;
751 	bool odd = !!(dspi->len & 1);
752 
753 	/* No accel for frames not multiple of 8 bits at the moment */
754 	if (xfer->bits_per_word % 8)
755 		goto no_accel;
756 
757 	if (!odd && dspi->len <= dspi->devtype_data->fifo_size * 2) {
758 		dspi->oper_bits_per_word = 16;
759 	} else if (odd && dspi->len <= dspi->devtype_data->fifo_size) {
760 		dspi->oper_bits_per_word = 8;
761 	} else {
762 		/* Start off with maximum supported by hardware */
763 		if (dspi->devtype_data->trans_mode == DSPI_XSPI_MODE)
764 			dspi->oper_bits_per_word = 32;
765 		else
766 			dspi->oper_bits_per_word = 16;
767 
768 		/*
769 		 * And go down only if the buffer can't be sent with
770 		 * words this big
771 		 */
772 		do {
773 			if (dspi->len >= DIV_ROUND_UP(dspi->oper_bits_per_word, 8))
774 				break;
775 
776 			dspi->oper_bits_per_word /= 2;
777 		} while (dspi->oper_bits_per_word > 8);
778 	}
779 
780 	if (xfer->bits_per_word == 8 && dspi->oper_bits_per_word == 32) {
781 		dspi->dev_to_host = dspi_8on32_dev_to_host;
782 		dspi->host_to_dev = dspi_8on32_host_to_dev;
783 	} else if (xfer->bits_per_word == 8 && dspi->oper_bits_per_word == 16) {
784 		dspi->dev_to_host = dspi_8on16_dev_to_host;
785 		dspi->host_to_dev = dspi_8on16_host_to_dev;
786 	} else if (xfer->bits_per_word == 16 && dspi->oper_bits_per_word == 32) {
787 		dspi->dev_to_host = dspi_16on32_dev_to_host;
788 		dspi->host_to_dev = dspi_16on32_host_to_dev;
789 	} else {
790 no_accel:
791 		dspi->dev_to_host = dspi_native_dev_to_host;
792 		dspi->host_to_dev = dspi_native_host_to_dev;
793 		dspi->oper_bits_per_word = xfer->bits_per_word;
794 	}
795 
796 	dspi->oper_word_size = DIV_ROUND_UP(dspi->oper_bits_per_word, 8);
797 
798 	/*
799 	 * Update CTAR here (code is common for XSPI and DMA modes).
800 	 * We will update CTARE in the portion specific to XSPI, when we
801 	 * also know the preload value (DTCP).
802 	 */
803 	regmap_write(dspi->regmap, SPI_CTAR(0),
804 		     dspi->cur_chip->ctar_val |
805 		     SPI_FRAME_BITS(dspi->oper_bits_per_word));
806 }
807 
808 static void dspi_fifo_write(struct fsl_dspi *dspi)
809 {
810 	int num_fifo_entries = dspi->devtype_data->fifo_size;
811 	struct spi_transfer *xfer = dspi->cur_transfer;
812 	struct spi_message *msg = dspi->cur_msg;
813 	int num_words, num_bytes;
814 
815 	dspi_setup_accel(dspi);
816 
817 	/* In XSPI mode each 32-bit word occupies 2 TX FIFO entries */
818 	if (dspi->oper_word_size == 4)
819 		num_fifo_entries /= 2;
820 
821 	/*
822 	 * Integer division intentionally trims off odd (or non-multiple of 4)
823 	 * numbers of bytes at the end of the buffer, which will be sent next
824 	 * time using a smaller oper_word_size.
825 	 */
826 	num_words = dspi->len / dspi->oper_word_size;
827 	if (num_words > num_fifo_entries)
828 		num_words = num_fifo_entries;
829 
830 	/* Update total number of bytes that were transferred */
831 	num_bytes = num_words * dspi->oper_word_size;
832 	msg->actual_length += num_bytes;
833 	dspi->progress += num_bytes / DIV_ROUND_UP(xfer->bits_per_word, 8);
834 
835 	/*
836 	 * Update shared variable for use in the next interrupt (both in
837 	 * dspi_fifo_read and in dspi_fifo_write).
838 	 */
839 	dspi->words_in_flight = num_words;
840 
841 	spi_take_timestamp_pre(dspi->ctlr, xfer, dspi->progress, !dspi->irq);
842 
843 	dspi_xspi_fifo_write(dspi, num_words);
844 	/*
845 	 * Everything after this point is in a potential race with the next
846 	 * interrupt, so we must never use dspi->words_in_flight again since it
847 	 * might already be modified by the next dspi_fifo_write.
848 	 */
849 
850 	spi_take_timestamp_post(dspi->ctlr, dspi->cur_transfer,
851 				dspi->progress, !dspi->irq);
852 }
853 
854 static int dspi_rxtx(struct fsl_dspi *dspi)
855 {
856 	dspi_fifo_read(dspi);
857 
858 	if (!dspi->len)
859 		/* Success! */
860 		return 0;
861 
862 	dspi_fifo_write(dspi);
863 
864 	return -EINPROGRESS;
865 }
866 
867 static int dspi_poll(struct fsl_dspi *dspi)
868 {
869 	int tries = 1000;
870 	u32 spi_sr;
871 
872 	do {
873 		regmap_read(dspi->regmap, SPI_SR, &spi_sr);
874 		regmap_write(dspi->regmap, SPI_SR, spi_sr);
875 
876 		if (spi_sr & SPI_SR_CMDTCF)
877 			break;
878 	} while (--tries);
879 
880 	if (!tries)
881 		return -ETIMEDOUT;
882 
883 	return dspi_rxtx(dspi);
884 }
885 
886 static irqreturn_t dspi_interrupt(int irq, void *dev_id)
887 {
888 	struct fsl_dspi *dspi = (struct fsl_dspi *)dev_id;
889 	u32 spi_sr;
890 
891 	regmap_read(dspi->regmap, SPI_SR, &spi_sr);
892 	regmap_write(dspi->regmap, SPI_SR, spi_sr);
893 
894 	if (!(spi_sr & SPI_SR_CMDTCF))
895 		return IRQ_NONE;
896 
897 	if (dspi_rxtx(dspi) == 0)
898 		complete(&dspi->xfer_done);
899 
900 	return IRQ_HANDLED;
901 }
902 
903 static void dspi_assert_cs(struct spi_device *spi, bool *cs)
904 {
905 	if (!spi_get_csgpiod(spi, 0) || *cs)
906 		return;
907 
908 	gpiod_set_value_cansleep(spi_get_csgpiod(spi, 0), true);
909 	*cs = true;
910 }
911 
912 static void dspi_deassert_cs(struct spi_device *spi, bool *cs)
913 {
914 	if (!spi_get_csgpiod(spi, 0) || !*cs)
915 		return;
916 
917 	gpiod_set_value_cansleep(spi_get_csgpiod(spi, 0), false);
918 	*cs = false;
919 }
920 
921 static int dspi_transfer_one_message(struct spi_controller *ctlr,
922 				     struct spi_message *message)
923 {
924 	struct fsl_dspi *dspi = spi_controller_get_devdata(ctlr);
925 	struct spi_device *spi = message->spi;
926 	struct spi_transfer *transfer;
927 	bool cs = false;
928 	int status = 0;
929 
930 	message->actual_length = 0;
931 
932 	list_for_each_entry(transfer, &message->transfers, transfer_list) {
933 		dspi->cur_transfer = transfer;
934 		dspi->cur_msg = message;
935 		dspi->cur_chip = spi_get_ctldata(spi);
936 
937 		dspi_assert_cs(spi, &cs);
938 
939 		/* Prepare command word for CMD FIFO */
940 		dspi->tx_cmd = SPI_PUSHR_CMD_CTAS(0);
941 		if (!spi_get_csgpiod(spi, 0))
942 			dspi->tx_cmd |= SPI_PUSHR_CMD_PCS(spi_get_chipselect(spi, 0));
943 
944 		if (list_is_last(&dspi->cur_transfer->transfer_list,
945 				 &dspi->cur_msg->transfers)) {
946 			/* Leave PCS activated after last transfer when
947 			 * cs_change is set.
948 			 */
949 			if (transfer->cs_change)
950 				dspi->tx_cmd |= SPI_PUSHR_CMD_CONT;
951 		} else {
952 			/* Keep PCS active between transfers in same message
953 			 * when cs_change is not set, and de-activate PCS
954 			 * between transfers in the same message when
955 			 * cs_change is set.
956 			 */
957 			if (!transfer->cs_change)
958 				dspi->tx_cmd |= SPI_PUSHR_CMD_CONT;
959 		}
960 
961 		dspi->tx = transfer->tx_buf;
962 		dspi->rx = transfer->rx_buf;
963 		dspi->len = transfer->len;
964 		dspi->progress = 0;
965 
966 		regmap_update_bits(dspi->regmap, SPI_MCR,
967 				   SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF,
968 				   SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF);
969 
970 		spi_take_timestamp_pre(dspi->ctlr, dspi->cur_transfer,
971 				       dspi->progress, !dspi->irq);
972 
973 		if (dspi->devtype_data->trans_mode == DSPI_DMA_MODE) {
974 			status = dspi_dma_xfer(dspi);
975 		} else {
976 			dspi_fifo_write(dspi);
977 
978 			if (dspi->irq) {
979 				wait_for_completion(&dspi->xfer_done);
980 				reinit_completion(&dspi->xfer_done);
981 			} else {
982 				do {
983 					status = dspi_poll(dspi);
984 				} while (status == -EINPROGRESS);
985 			}
986 		}
987 		if (status)
988 			break;
989 
990 		spi_transfer_delay_exec(transfer);
991 
992 		if (!(dspi->tx_cmd & SPI_PUSHR_CMD_CONT))
993 			dspi_deassert_cs(spi, &cs);
994 	}
995 
996 	message->status = status;
997 	spi_finalize_current_message(ctlr);
998 
999 	return status;
1000 }
1001 
1002 static int dspi_setup(struct spi_device *spi)
1003 {
1004 	struct fsl_dspi *dspi = spi_controller_get_devdata(spi->controller);
1005 	u32 period_ns = DIV_ROUND_UP(NSEC_PER_SEC, spi->max_speed_hz);
1006 	unsigned char br = 0, pbr = 0, pcssck = 0, cssck = 0;
1007 	u32 quarter_period_ns = DIV_ROUND_UP(period_ns, 4);
1008 	u32 cs_sck_delay = 0, sck_cs_delay = 0;
1009 	struct fsl_dspi_platform_data *pdata;
1010 	unsigned char pasc = 0, asc = 0;
1011 	struct chip_data *chip;
1012 	unsigned long clkrate;
1013 	bool cs = true;
1014 
1015 	/* Only alloc on first setup */
1016 	chip = spi_get_ctldata(spi);
1017 	if (chip == NULL) {
1018 		chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
1019 		if (!chip)
1020 			return -ENOMEM;
1021 	}
1022 
1023 	pdata = dev_get_platdata(&dspi->pdev->dev);
1024 
1025 	if (!pdata) {
1026 		of_property_read_u32(spi->dev.of_node, "fsl,spi-cs-sck-delay",
1027 				     &cs_sck_delay);
1028 
1029 		of_property_read_u32(spi->dev.of_node, "fsl,spi-sck-cs-delay",
1030 				     &sck_cs_delay);
1031 	} else {
1032 		cs_sck_delay = pdata->cs_sck_delay;
1033 		sck_cs_delay = pdata->sck_cs_delay;
1034 	}
1035 
1036 	/* Since tCSC and tASC apply to continuous transfers too, avoid SCK
1037 	 * glitches of half a cycle by never allowing tCSC + tASC to go below
1038 	 * half a SCK period.
1039 	 */
1040 	if (cs_sck_delay < quarter_period_ns)
1041 		cs_sck_delay = quarter_period_ns;
1042 	if (sck_cs_delay < quarter_period_ns)
1043 		sck_cs_delay = quarter_period_ns;
1044 
1045 	dev_dbg(&spi->dev,
1046 		"DSPI controller timing params: CS-to-SCK delay %u ns, SCK-to-CS delay %u ns\n",
1047 		cs_sck_delay, sck_cs_delay);
1048 
1049 	clkrate = clk_get_rate(dspi->clk);
1050 	hz_to_spi_baud(&pbr, &br, spi->max_speed_hz, clkrate);
1051 
1052 	/* Set PCS to SCK delay scale values */
1053 	ns_delay_scale(&pcssck, &cssck, cs_sck_delay, clkrate);
1054 
1055 	/* Set After SCK delay scale values */
1056 	ns_delay_scale(&pasc, &asc, sck_cs_delay, clkrate);
1057 
1058 	chip->ctar_val = 0;
1059 	if (spi->mode & SPI_CPOL)
1060 		chip->ctar_val |= SPI_CTAR_CPOL;
1061 	if (spi->mode & SPI_CPHA)
1062 		chip->ctar_val |= SPI_CTAR_CPHA;
1063 
1064 	if (!spi_controller_is_slave(dspi->ctlr)) {
1065 		chip->ctar_val |= SPI_CTAR_PCSSCK(pcssck) |
1066 				  SPI_CTAR_CSSCK(cssck) |
1067 				  SPI_CTAR_PASC(pasc) |
1068 				  SPI_CTAR_ASC(asc) |
1069 				  SPI_CTAR_PBR(pbr) |
1070 				  SPI_CTAR_BR(br);
1071 
1072 		if (spi->mode & SPI_LSB_FIRST)
1073 			chip->ctar_val |= SPI_CTAR_LSBFE;
1074 	}
1075 
1076 	gpiod_direction_output(spi_get_csgpiod(spi, 0), false);
1077 	dspi_deassert_cs(spi, &cs);
1078 
1079 	spi_set_ctldata(spi, chip);
1080 
1081 	return 0;
1082 }
1083 
1084 static void dspi_cleanup(struct spi_device *spi)
1085 {
1086 	struct chip_data *chip = spi_get_ctldata(spi);
1087 
1088 	dev_dbg(&spi->dev, "spi_device %u.%u cleanup\n",
1089 		spi->controller->bus_num, spi_get_chipselect(spi, 0));
1090 
1091 	kfree(chip);
1092 }
1093 
1094 static const struct of_device_id fsl_dspi_dt_ids[] = {
1095 	{
1096 		.compatible = "fsl,vf610-dspi",
1097 		.data = &devtype_data[VF610],
1098 	}, {
1099 		.compatible = "fsl,ls1021a-v1.0-dspi",
1100 		.data = &devtype_data[LS1021A],
1101 	}, {
1102 		.compatible = "fsl,ls1012a-dspi",
1103 		.data = &devtype_data[LS1012A],
1104 	}, {
1105 		.compatible = "fsl,ls1028a-dspi",
1106 		.data = &devtype_data[LS1028A],
1107 	}, {
1108 		.compatible = "fsl,ls1043a-dspi",
1109 		.data = &devtype_data[LS1043A],
1110 	}, {
1111 		.compatible = "fsl,ls1046a-dspi",
1112 		.data = &devtype_data[LS1046A],
1113 	}, {
1114 		.compatible = "fsl,ls2080a-dspi",
1115 		.data = &devtype_data[LS2080A],
1116 	}, {
1117 		.compatible = "fsl,ls2085a-dspi",
1118 		.data = &devtype_data[LS2085A],
1119 	}, {
1120 		.compatible = "fsl,lx2160a-dspi",
1121 		.data = &devtype_data[LX2160A],
1122 	},
1123 	{ /* sentinel */ }
1124 };
1125 MODULE_DEVICE_TABLE(of, fsl_dspi_dt_ids);
1126 
1127 #ifdef CONFIG_PM_SLEEP
1128 static int dspi_suspend(struct device *dev)
1129 {
1130 	struct fsl_dspi *dspi = dev_get_drvdata(dev);
1131 
1132 	if (dspi->irq)
1133 		disable_irq(dspi->irq);
1134 	spi_controller_suspend(dspi->ctlr);
1135 	clk_disable_unprepare(dspi->clk);
1136 
1137 	pinctrl_pm_select_sleep_state(dev);
1138 
1139 	return 0;
1140 }
1141 
1142 static int dspi_resume(struct device *dev)
1143 {
1144 	struct fsl_dspi *dspi = dev_get_drvdata(dev);
1145 	int ret;
1146 
1147 	pinctrl_pm_select_default_state(dev);
1148 
1149 	ret = clk_prepare_enable(dspi->clk);
1150 	if (ret)
1151 		return ret;
1152 	spi_controller_resume(dspi->ctlr);
1153 	if (dspi->irq)
1154 		enable_irq(dspi->irq);
1155 
1156 	return 0;
1157 }
1158 #endif /* CONFIG_PM_SLEEP */
1159 
1160 static SIMPLE_DEV_PM_OPS(dspi_pm, dspi_suspend, dspi_resume);
1161 
1162 static const struct regmap_range dspi_volatile_ranges[] = {
1163 	regmap_reg_range(SPI_MCR, SPI_TCR),
1164 	regmap_reg_range(SPI_SR, SPI_SR),
1165 	regmap_reg_range(SPI_PUSHR, SPI_RXFR3),
1166 };
1167 
1168 static const struct regmap_access_table dspi_volatile_table = {
1169 	.yes_ranges	= dspi_volatile_ranges,
1170 	.n_yes_ranges	= ARRAY_SIZE(dspi_volatile_ranges),
1171 };
1172 
1173 static const struct regmap_config dspi_regmap_config = {
1174 	.reg_bits	= 32,
1175 	.val_bits	= 32,
1176 	.reg_stride	= 4,
1177 	.max_register	= 0x88,
1178 	.volatile_table	= &dspi_volatile_table,
1179 };
1180 
1181 static const struct regmap_range dspi_xspi_volatile_ranges[] = {
1182 	regmap_reg_range(SPI_MCR, SPI_TCR),
1183 	regmap_reg_range(SPI_SR, SPI_SR),
1184 	regmap_reg_range(SPI_PUSHR, SPI_RXFR3),
1185 	regmap_reg_range(SPI_SREX, SPI_SREX),
1186 };
1187 
1188 static const struct regmap_access_table dspi_xspi_volatile_table = {
1189 	.yes_ranges	= dspi_xspi_volatile_ranges,
1190 	.n_yes_ranges	= ARRAY_SIZE(dspi_xspi_volatile_ranges),
1191 };
1192 
1193 static const struct regmap_config dspi_xspi_regmap_config[] = {
1194 	{
1195 		.reg_bits	= 32,
1196 		.val_bits	= 32,
1197 		.reg_stride	= 4,
1198 		.max_register	= 0x13c,
1199 		.volatile_table	= &dspi_xspi_volatile_table,
1200 	},
1201 	{
1202 		.name		= "pushr",
1203 		.reg_bits	= 16,
1204 		.val_bits	= 16,
1205 		.reg_stride	= 2,
1206 		.max_register	= 0x2,
1207 	},
1208 };
1209 
1210 static int dspi_init(struct fsl_dspi *dspi)
1211 {
1212 	unsigned int mcr;
1213 
1214 	/* Set idle states for all chip select signals to high */
1215 	mcr = SPI_MCR_PCSIS(GENMASK(dspi->ctlr->max_native_cs - 1, 0));
1216 
1217 	if (dspi->devtype_data->trans_mode == DSPI_XSPI_MODE)
1218 		mcr |= SPI_MCR_XSPI;
1219 	if (!spi_controller_is_slave(dspi->ctlr))
1220 		mcr |= SPI_MCR_MASTER;
1221 
1222 	regmap_write(dspi->regmap, SPI_MCR, mcr);
1223 	regmap_write(dspi->regmap, SPI_SR, SPI_SR_CLEAR);
1224 
1225 	switch (dspi->devtype_data->trans_mode) {
1226 	case DSPI_XSPI_MODE:
1227 		regmap_write(dspi->regmap, SPI_RSER, SPI_RSER_CMDTCFE);
1228 		break;
1229 	case DSPI_DMA_MODE:
1230 		regmap_write(dspi->regmap, SPI_RSER,
1231 			     SPI_RSER_TFFFE | SPI_RSER_TFFFD |
1232 			     SPI_RSER_RFDFE | SPI_RSER_RFDFD);
1233 		break;
1234 	default:
1235 		dev_err(&dspi->pdev->dev, "unsupported trans_mode %u\n",
1236 			dspi->devtype_data->trans_mode);
1237 		return -EINVAL;
1238 	}
1239 
1240 	return 0;
1241 }
1242 
1243 static int dspi_slave_abort(struct spi_master *master)
1244 {
1245 	struct fsl_dspi *dspi = spi_master_get_devdata(master);
1246 
1247 	/*
1248 	 * Terminate all pending DMA transactions for the SPI working
1249 	 * in SLAVE mode.
1250 	 */
1251 	if (dspi->devtype_data->trans_mode == DSPI_DMA_MODE) {
1252 		dmaengine_terminate_sync(dspi->dma->chan_rx);
1253 		dmaengine_terminate_sync(dspi->dma->chan_tx);
1254 	}
1255 
1256 	/* Clear the internal DSPI RX and TX FIFO buffers */
1257 	regmap_update_bits(dspi->regmap, SPI_MCR,
1258 			   SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF,
1259 			   SPI_MCR_CLR_TXF | SPI_MCR_CLR_RXF);
1260 
1261 	return 0;
1262 }
1263 
1264 static int dspi_probe(struct platform_device *pdev)
1265 {
1266 	struct device_node *np = pdev->dev.of_node;
1267 	const struct regmap_config *regmap_config;
1268 	struct fsl_dspi_platform_data *pdata;
1269 	struct spi_controller *ctlr;
1270 	int ret, cs_num, bus_num = -1;
1271 	struct fsl_dspi *dspi;
1272 	struct resource *res;
1273 	void __iomem *base;
1274 	bool big_endian;
1275 
1276 	dspi = devm_kzalloc(&pdev->dev, sizeof(*dspi), GFP_KERNEL);
1277 	if (!dspi)
1278 		return -ENOMEM;
1279 
1280 	ctlr = spi_alloc_master(&pdev->dev, 0);
1281 	if (!ctlr)
1282 		return -ENOMEM;
1283 
1284 	spi_controller_set_devdata(ctlr, dspi);
1285 	platform_set_drvdata(pdev, dspi);
1286 
1287 	dspi->pdev = pdev;
1288 	dspi->ctlr = ctlr;
1289 
1290 	ctlr->setup = dspi_setup;
1291 	ctlr->transfer_one_message = dspi_transfer_one_message;
1292 	ctlr->dev.of_node = pdev->dev.of_node;
1293 
1294 	ctlr->cleanup = dspi_cleanup;
1295 	ctlr->slave_abort = dspi_slave_abort;
1296 	ctlr->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;
1297 	ctlr->use_gpio_descriptors = true;
1298 
1299 	pdata = dev_get_platdata(&pdev->dev);
1300 	if (pdata) {
1301 		ctlr->num_chipselect = ctlr->max_native_cs = pdata->cs_num;
1302 		ctlr->bus_num = pdata->bus_num;
1303 
1304 		/* Only Coldfire uses platform data */
1305 		dspi->devtype_data = &devtype_data[MCF5441X];
1306 		big_endian = true;
1307 	} else {
1308 
1309 		ret = of_property_read_u32(np, "spi-num-chipselects", &cs_num);
1310 		if (ret < 0) {
1311 			dev_err(&pdev->dev, "can't get spi-num-chipselects\n");
1312 			goto out_ctlr_put;
1313 		}
1314 		ctlr->num_chipselect = ctlr->max_native_cs = cs_num;
1315 
1316 		of_property_read_u32(np, "bus-num", &bus_num);
1317 		ctlr->bus_num = bus_num;
1318 
1319 		if (of_property_read_bool(np, "spi-slave"))
1320 			ctlr->slave = true;
1321 
1322 		dspi->devtype_data = of_device_get_match_data(&pdev->dev);
1323 		if (!dspi->devtype_data) {
1324 			dev_err(&pdev->dev, "can't get devtype_data\n");
1325 			ret = -EFAULT;
1326 			goto out_ctlr_put;
1327 		}
1328 
1329 		big_endian = of_device_is_big_endian(np);
1330 	}
1331 	if (big_endian) {
1332 		dspi->pushr_cmd = 0;
1333 		dspi->pushr_tx = 2;
1334 	} else {
1335 		dspi->pushr_cmd = 2;
1336 		dspi->pushr_tx = 0;
1337 	}
1338 
1339 	if (dspi->devtype_data->trans_mode == DSPI_XSPI_MODE)
1340 		ctlr->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
1341 	else
1342 		ctlr->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16);
1343 
1344 	base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
1345 	if (IS_ERR(base)) {
1346 		ret = PTR_ERR(base);
1347 		goto out_ctlr_put;
1348 	}
1349 
1350 	if (dspi->devtype_data->trans_mode == DSPI_XSPI_MODE)
1351 		regmap_config = &dspi_xspi_regmap_config[0];
1352 	else
1353 		regmap_config = &dspi_regmap_config;
1354 	dspi->regmap = devm_regmap_init_mmio(&pdev->dev, base, regmap_config);
1355 	if (IS_ERR(dspi->regmap)) {
1356 		dev_err(&pdev->dev, "failed to init regmap: %ld\n",
1357 				PTR_ERR(dspi->regmap));
1358 		ret = PTR_ERR(dspi->regmap);
1359 		goto out_ctlr_put;
1360 	}
1361 
1362 	if (dspi->devtype_data->trans_mode == DSPI_XSPI_MODE) {
1363 		dspi->regmap_pushr = devm_regmap_init_mmio(
1364 			&pdev->dev, base + SPI_PUSHR,
1365 			&dspi_xspi_regmap_config[1]);
1366 		if (IS_ERR(dspi->regmap_pushr)) {
1367 			dev_err(&pdev->dev,
1368 				"failed to init pushr regmap: %ld\n",
1369 				PTR_ERR(dspi->regmap_pushr));
1370 			ret = PTR_ERR(dspi->regmap_pushr);
1371 			goto out_ctlr_put;
1372 		}
1373 	}
1374 
1375 	dspi->clk = devm_clk_get(&pdev->dev, "dspi");
1376 	if (IS_ERR(dspi->clk)) {
1377 		ret = PTR_ERR(dspi->clk);
1378 		dev_err(&pdev->dev, "unable to get clock\n");
1379 		goto out_ctlr_put;
1380 	}
1381 	ret = clk_prepare_enable(dspi->clk);
1382 	if (ret)
1383 		goto out_ctlr_put;
1384 
1385 	ret = dspi_init(dspi);
1386 	if (ret)
1387 		goto out_clk_put;
1388 
1389 	dspi->irq = platform_get_irq(pdev, 0);
1390 	if (dspi->irq <= 0) {
1391 		dev_info(&pdev->dev,
1392 			 "can't get platform irq, using poll mode\n");
1393 		dspi->irq = 0;
1394 		goto poll_mode;
1395 	}
1396 
1397 	init_completion(&dspi->xfer_done);
1398 
1399 	ret = request_threaded_irq(dspi->irq, dspi_interrupt, NULL,
1400 				   IRQF_SHARED, pdev->name, dspi);
1401 	if (ret < 0) {
1402 		dev_err(&pdev->dev, "Unable to attach DSPI interrupt\n");
1403 		goto out_clk_put;
1404 	}
1405 
1406 poll_mode:
1407 
1408 	if (dspi->devtype_data->trans_mode == DSPI_DMA_MODE) {
1409 		ret = dspi_request_dma(dspi, res->start);
1410 		if (ret < 0) {
1411 			dev_err(&pdev->dev, "can't get dma channels\n");
1412 			goto out_free_irq;
1413 		}
1414 	}
1415 
1416 	ctlr->max_speed_hz =
1417 		clk_get_rate(dspi->clk) / dspi->devtype_data->max_clock_factor;
1418 
1419 	if (dspi->devtype_data->trans_mode != DSPI_DMA_MODE)
1420 		ctlr->ptp_sts_supported = true;
1421 
1422 	ret = spi_register_controller(ctlr);
1423 	if (ret != 0) {
1424 		dev_err(&pdev->dev, "Problem registering DSPI ctlr\n");
1425 		goto out_release_dma;
1426 	}
1427 
1428 	return ret;
1429 
1430 out_release_dma:
1431 	dspi_release_dma(dspi);
1432 out_free_irq:
1433 	if (dspi->irq)
1434 		free_irq(dspi->irq, dspi);
1435 out_clk_put:
1436 	clk_disable_unprepare(dspi->clk);
1437 out_ctlr_put:
1438 	spi_controller_put(ctlr);
1439 
1440 	return ret;
1441 }
1442 
1443 static void dspi_remove(struct platform_device *pdev)
1444 {
1445 	struct fsl_dspi *dspi = platform_get_drvdata(pdev);
1446 
1447 	/* Disconnect from the SPI framework */
1448 	spi_unregister_controller(dspi->ctlr);
1449 
1450 	/* Disable RX and TX */
1451 	regmap_update_bits(dspi->regmap, SPI_MCR,
1452 			   SPI_MCR_DIS_TXF | SPI_MCR_DIS_RXF,
1453 			   SPI_MCR_DIS_TXF | SPI_MCR_DIS_RXF);
1454 
1455 	/* Stop Running */
1456 	regmap_update_bits(dspi->regmap, SPI_MCR, SPI_MCR_HALT, SPI_MCR_HALT);
1457 
1458 	dspi_release_dma(dspi);
1459 	if (dspi->irq)
1460 		free_irq(dspi->irq, dspi);
1461 	clk_disable_unprepare(dspi->clk);
1462 }
1463 
1464 static void dspi_shutdown(struct platform_device *pdev)
1465 {
1466 	dspi_remove(pdev);
1467 }
1468 
1469 static struct platform_driver fsl_dspi_driver = {
1470 	.driver.name		= DRIVER_NAME,
1471 	.driver.of_match_table	= fsl_dspi_dt_ids,
1472 	.driver.owner		= THIS_MODULE,
1473 	.driver.pm		= &dspi_pm,
1474 	.probe			= dspi_probe,
1475 	.remove_new		= dspi_remove,
1476 	.shutdown		= dspi_shutdown,
1477 };
1478 module_platform_driver(fsl_dspi_driver);
1479 
1480 MODULE_DESCRIPTION("Freescale DSPI Controller Driver");
1481 MODULE_LICENSE("GPL");
1482 MODULE_ALIAS("platform:" DRIVER_NAME);
1483