xref: /linux/drivers/spi/spi-ti-qspi.c (revision 0262163136de813894cb172aa8ccf762b92e5fd7)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * TI QSPI driver
4  *
5  * Copyright (C) 2013 Texas Instruments Incorporated - https://www.ti.com
6  * Author: Sourav Poddar <sourav.poddar@ti.com>
7  */
8 
9 #include <linux/kernel.h>
10 #include <linux/init.h>
11 #include <linux/interrupt.h>
12 #include <linux/module.h>
13 #include <linux/device.h>
14 #include <linux/delay.h>
15 #include <linux/dma-mapping.h>
16 #include <linux/dmaengine.h>
17 #include <linux/omap-dma.h>
18 #include <linux/platform_device.h>
19 #include <linux/err.h>
20 #include <linux/clk.h>
21 #include <linux/io.h>
22 #include <linux/slab.h>
23 #include <linux/pm_runtime.h>
24 #include <linux/of.h>
25 #include <linux/pinctrl/consumer.h>
26 #include <linux/mfd/syscon.h>
27 #include <linux/regmap.h>
28 #include <linux/sizes.h>
29 
30 #include <linux/spi/spi.h>
31 #include <linux/spi/spi-mem.h>
32 
33 struct ti_qspi_regs {
34 	u32 clkctrl;
35 };
36 
37 struct ti_qspi {
38 	struct completion	transfer_complete;
39 
40 	/* list synchronization */
41 	struct mutex            list_lock;
42 
43 	struct spi_controller	*host;
44 	void __iomem            *base;
45 	void __iomem            *mmap_base;
46 	size_t			mmap_size;
47 	struct regmap		*ctrl_base;
48 	unsigned int		ctrl_reg;
49 	struct clk		*fclk;
50 	struct device           *dev;
51 
52 	struct ti_qspi_regs     ctx_reg;
53 
54 	dma_addr_t		mmap_phys_base;
55 	dma_addr_t		rx_bb_dma_addr;
56 	void			*rx_bb_addr;
57 	struct dma_chan		*rx_chan;
58 
59 	u32 cmd;
60 	u32 dc;
61 
62 	bool mmap_enabled;
63 	int current_cs;
64 };
65 
66 #define QSPI_PID			(0x0)
67 #define QSPI_SYSCONFIG			(0x10)
68 #define QSPI_SPI_CLOCK_CNTRL_REG	(0x40)
69 #define QSPI_SPI_DC_REG			(0x44)
70 #define QSPI_SPI_CMD_REG		(0x48)
71 #define QSPI_SPI_STATUS_REG		(0x4c)
72 #define QSPI_SPI_DATA_REG		(0x50)
73 #define QSPI_SPI_SETUP_REG(n)		((0x54 + 4 * n))
74 #define QSPI_SPI_SWITCH_REG		(0x64)
75 #define QSPI_SPI_DATA_REG_1		(0x68)
76 #define QSPI_SPI_DATA_REG_2		(0x6c)
77 #define QSPI_SPI_DATA_REG_3		(0x70)
78 
79 #define QSPI_COMPLETION_TIMEOUT		msecs_to_jiffies(2000)
80 
81 /* Clock Control */
82 #define QSPI_CLK_EN			(1 << 31)
83 #define QSPI_CLK_DIV_MAX		0xffff
84 
85 /* Command */
86 #define QSPI_EN_CS(n)			(n << 28)
87 #define QSPI_WLEN(n)			((n - 1) << 19)
88 #define QSPI_3_PIN			(1 << 18)
89 #define QSPI_RD_SNGL			(1 << 16)
90 #define QSPI_WR_SNGL			(2 << 16)
91 #define QSPI_RD_DUAL			(3 << 16)
92 #define QSPI_RD_QUAD			(7 << 16)
93 #define QSPI_INVAL			(4 << 16)
94 #define QSPI_FLEN(n)			((n - 1) << 0)
95 #define QSPI_WLEN_MAX_BITS		128
96 #define QSPI_WLEN_MAX_BYTES		16
97 #define QSPI_WLEN_MASK			QSPI_WLEN(QSPI_WLEN_MAX_BITS)
98 
99 /* STATUS REGISTER */
100 #define BUSY				0x01
101 #define WC				0x02
102 
103 /* Device Control */
104 #define QSPI_DD(m, n)			(m << (3 + n * 8))
105 #define QSPI_CKPHA(n)			(1 << (2 + n * 8))
106 #define QSPI_CSPOL(n)			(1 << (1 + n * 8))
107 #define QSPI_CKPOL(n)			(1 << (n * 8))
108 
109 #define	QSPI_FRAME			4096
110 
111 #define QSPI_AUTOSUSPEND_TIMEOUT         2000
112 
113 #define MEM_CS_EN(n)			((n + 1) << 8)
114 #define MEM_CS_MASK			(7 << 8)
115 
116 #define MM_SWITCH			0x1
117 
118 #define QSPI_SETUP_RD_NORMAL		(0x0 << 12)
119 #define QSPI_SETUP_RD_DUAL		(0x1 << 12)
120 #define QSPI_SETUP_RD_QUAD		(0x3 << 12)
121 #define QSPI_SETUP_ADDR_SHIFT		8
122 #define QSPI_SETUP_DUMMY_SHIFT		10
123 
124 #define QSPI_DMA_BUFFER_SIZE            SZ_64K
125 
ti_qspi_read(struct ti_qspi * qspi,unsigned long reg)126 static inline unsigned long ti_qspi_read(struct ti_qspi *qspi,
127 		unsigned long reg)
128 {
129 	return readl(qspi->base + reg);
130 }
131 
ti_qspi_write(struct ti_qspi * qspi,unsigned long val,unsigned long reg)132 static inline void ti_qspi_write(struct ti_qspi *qspi,
133 		unsigned long val, unsigned long reg)
134 {
135 	writel(val, qspi->base + reg);
136 }
137 
ti_qspi_setup(struct spi_device * spi)138 static int ti_qspi_setup(struct spi_device *spi)
139 {
140 	struct ti_qspi	*qspi = spi_controller_get_devdata(spi->controller);
141 	int ret;
142 
143 	if (spi->controller->busy) {
144 		dev_dbg(qspi->dev, "host busy doing other transfers\n");
145 		return -EBUSY;
146 	}
147 
148 	if (!qspi->host->max_speed_hz) {
149 		dev_err(qspi->dev, "spi max frequency not defined\n");
150 		return -EINVAL;
151 	}
152 
153 	spi->max_speed_hz = min(spi->max_speed_hz, qspi->host->max_speed_hz);
154 
155 	ret = pm_runtime_resume_and_get(qspi->dev);
156 	if (ret < 0) {
157 		dev_err(qspi->dev, "pm_runtime_get_sync() failed\n");
158 		return ret;
159 	}
160 
161 	ret = pm_runtime_put_autosuspend(qspi->dev);
162 	if (ret < 0) {
163 		dev_err(qspi->dev, "pm_runtime_put_autosuspend() failed\n");
164 		return ret;
165 	}
166 
167 	return 0;
168 }
169 
ti_qspi_setup_clk(struct ti_qspi * qspi,u32 speed_hz)170 static void ti_qspi_setup_clk(struct ti_qspi *qspi, u32 speed_hz)
171 {
172 	struct ti_qspi_regs *ctx_reg = &qspi->ctx_reg;
173 	int clk_div;
174 	u32 clk_ctrl_reg, clk_rate, clk_ctrl_new;
175 
176 	clk_rate = clk_get_rate(qspi->fclk);
177 	clk_div = DIV_ROUND_UP(clk_rate, speed_hz) - 1;
178 	clk_div = clamp(clk_div, 0, QSPI_CLK_DIV_MAX);
179 	dev_dbg(qspi->dev, "hz: %d, clock divider %d\n", speed_hz, clk_div);
180 
181 	pm_runtime_resume_and_get(qspi->dev);
182 
183 	clk_ctrl_new = QSPI_CLK_EN | clk_div;
184 	if (ctx_reg->clkctrl != clk_ctrl_new) {
185 		clk_ctrl_reg = ti_qspi_read(qspi, QSPI_SPI_CLOCK_CNTRL_REG);
186 
187 		clk_ctrl_reg &= ~QSPI_CLK_EN;
188 
189 		/* disable SCLK */
190 		ti_qspi_write(qspi, clk_ctrl_reg, QSPI_SPI_CLOCK_CNTRL_REG);
191 
192 		/* enable SCLK */
193 		ti_qspi_write(qspi, clk_ctrl_new, QSPI_SPI_CLOCK_CNTRL_REG);
194 		ctx_reg->clkctrl = clk_ctrl_new;
195 	}
196 
197 	pm_runtime_put_autosuspend(qspi->dev);
198 }
199 
ti_qspi_restore_ctx(struct ti_qspi * qspi)200 static void ti_qspi_restore_ctx(struct ti_qspi *qspi)
201 {
202 	struct ti_qspi_regs *ctx_reg = &qspi->ctx_reg;
203 
204 	ti_qspi_write(qspi, ctx_reg->clkctrl, QSPI_SPI_CLOCK_CNTRL_REG);
205 }
206 
qspi_is_busy(struct ti_qspi * qspi)207 static inline u32 qspi_is_busy(struct ti_qspi *qspi)
208 {
209 	u32 stat;
210 	unsigned long timeout = jiffies + QSPI_COMPLETION_TIMEOUT;
211 
212 	stat = ti_qspi_read(qspi, QSPI_SPI_STATUS_REG);
213 	while ((stat & BUSY) && time_after(timeout, jiffies)) {
214 		cpu_relax();
215 		stat = ti_qspi_read(qspi, QSPI_SPI_STATUS_REG);
216 	}
217 
218 	WARN(stat & BUSY, "qspi busy\n");
219 	return stat & BUSY;
220 }
221 
ti_qspi_poll_wc(struct ti_qspi * qspi)222 static inline int ti_qspi_poll_wc(struct ti_qspi *qspi)
223 {
224 	u32 stat;
225 	unsigned long timeout = jiffies + QSPI_COMPLETION_TIMEOUT;
226 
227 	do {
228 		stat = ti_qspi_read(qspi, QSPI_SPI_STATUS_REG);
229 		if (stat & WC)
230 			return 0;
231 		cpu_relax();
232 	} while (time_after(timeout, jiffies));
233 
234 	stat = ti_qspi_read(qspi, QSPI_SPI_STATUS_REG);
235 	if (stat & WC)
236 		return 0;
237 	return  -ETIMEDOUT;
238 }
239 
qspi_write_msg(struct ti_qspi * qspi,struct spi_transfer * t,int count)240 static int qspi_write_msg(struct ti_qspi *qspi, struct spi_transfer *t,
241 			  int count)
242 {
243 	int wlen, xfer_len;
244 	unsigned int cmd;
245 	const u8 *txbuf;
246 	u32 data;
247 
248 	txbuf = t->tx_buf;
249 	cmd = qspi->cmd | QSPI_WR_SNGL;
250 	wlen = t->bits_per_word >> 3;	/* in bytes */
251 	xfer_len = wlen;
252 
253 	while (count) {
254 		if (qspi_is_busy(qspi))
255 			return -EBUSY;
256 
257 		switch (wlen) {
258 		case 1:
259 			dev_dbg(qspi->dev, "tx cmd %08x dc %08x data %02x\n",
260 					cmd, qspi->dc, *txbuf);
261 			if (count >= QSPI_WLEN_MAX_BYTES) {
262 				u32 *txp = (u32 *)txbuf;
263 
264 				data = cpu_to_be32(*txp++);
265 				writel(data, qspi->base +
266 				       QSPI_SPI_DATA_REG_3);
267 				data = cpu_to_be32(*txp++);
268 				writel(data, qspi->base +
269 				       QSPI_SPI_DATA_REG_2);
270 				data = cpu_to_be32(*txp++);
271 				writel(data, qspi->base +
272 				       QSPI_SPI_DATA_REG_1);
273 				data = cpu_to_be32(*txp++);
274 				writel(data, qspi->base +
275 				       QSPI_SPI_DATA_REG);
276 				xfer_len = QSPI_WLEN_MAX_BYTES;
277 				cmd |= QSPI_WLEN(QSPI_WLEN_MAX_BITS);
278 			} else {
279 				writeb(*txbuf, qspi->base + QSPI_SPI_DATA_REG);
280 				cmd = qspi->cmd | QSPI_WR_SNGL;
281 				xfer_len = wlen;
282 				cmd |= QSPI_WLEN(wlen);
283 			}
284 			break;
285 		case 2:
286 			dev_dbg(qspi->dev, "tx cmd %08x dc %08x data %04x\n",
287 					cmd, qspi->dc, *txbuf);
288 			writew(*((u16 *)txbuf), qspi->base + QSPI_SPI_DATA_REG);
289 			break;
290 		case 4:
291 			dev_dbg(qspi->dev, "tx cmd %08x dc %08x data %08x\n",
292 					cmd, qspi->dc, *txbuf);
293 			writel(*((u32 *)txbuf), qspi->base + QSPI_SPI_DATA_REG);
294 			break;
295 		}
296 
297 		ti_qspi_write(qspi, cmd, QSPI_SPI_CMD_REG);
298 		if (ti_qspi_poll_wc(qspi)) {
299 			dev_err(qspi->dev, "write timed out\n");
300 			return -ETIMEDOUT;
301 		}
302 		txbuf += xfer_len;
303 		count -= xfer_len;
304 	}
305 
306 	return 0;
307 }
308 
qspi_read_msg(struct ti_qspi * qspi,struct spi_transfer * t,int count)309 static int qspi_read_msg(struct ti_qspi *qspi, struct spi_transfer *t,
310 			 int count)
311 {
312 	int wlen;
313 	unsigned int cmd;
314 	u32 rx;
315 	u8 rxlen, rx_wlen;
316 	u8 *rxbuf;
317 
318 	rxbuf = t->rx_buf;
319 	cmd = qspi->cmd;
320 	switch (t->rx_nbits) {
321 	case SPI_NBITS_DUAL:
322 		cmd |= QSPI_RD_DUAL;
323 		break;
324 	case SPI_NBITS_QUAD:
325 		cmd |= QSPI_RD_QUAD;
326 		break;
327 	default:
328 		cmd |= QSPI_RD_SNGL;
329 		break;
330 	}
331 	wlen = t->bits_per_word >> 3;	/* in bytes */
332 	rx_wlen = wlen;
333 
334 	while (count) {
335 		dev_dbg(qspi->dev, "rx cmd %08x dc %08x\n", cmd, qspi->dc);
336 		if (qspi_is_busy(qspi))
337 			return -EBUSY;
338 
339 		switch (wlen) {
340 		case 1:
341 			/*
342 			 * Optimize the 8-bit words transfers, as used by
343 			 * the SPI flash devices.
344 			 */
345 			if (count >= QSPI_WLEN_MAX_BYTES) {
346 				rxlen = QSPI_WLEN_MAX_BYTES;
347 			} else {
348 				rxlen = min(count, 4);
349 			}
350 			rx_wlen = rxlen << 3;
351 			cmd &= ~QSPI_WLEN_MASK;
352 			cmd |= QSPI_WLEN(rx_wlen);
353 			break;
354 		default:
355 			rxlen = wlen;
356 			break;
357 		}
358 
359 		ti_qspi_write(qspi, cmd, QSPI_SPI_CMD_REG);
360 		if (ti_qspi_poll_wc(qspi)) {
361 			dev_err(qspi->dev, "read timed out\n");
362 			return -ETIMEDOUT;
363 		}
364 
365 		switch (wlen) {
366 		case 1:
367 			/*
368 			 * Optimize the 8-bit words transfers, as used by
369 			 * the SPI flash devices.
370 			 */
371 			if (count >= QSPI_WLEN_MAX_BYTES) {
372 				u32 *rxp = (u32 *) rxbuf;
373 				rx = readl(qspi->base + QSPI_SPI_DATA_REG_3);
374 				*rxp++ = be32_to_cpu(rx);
375 				rx = readl(qspi->base + QSPI_SPI_DATA_REG_2);
376 				*rxp++ = be32_to_cpu(rx);
377 				rx = readl(qspi->base + QSPI_SPI_DATA_REG_1);
378 				*rxp++ = be32_to_cpu(rx);
379 				rx = readl(qspi->base + QSPI_SPI_DATA_REG);
380 				*rxp++ = be32_to_cpu(rx);
381 			} else {
382 				u8 *rxp = rxbuf;
383 				rx = readl(qspi->base + QSPI_SPI_DATA_REG);
384 				if (rx_wlen >= 8)
385 					*rxp++ = rx >> (rx_wlen - 8);
386 				if (rx_wlen >= 16)
387 					*rxp++ = rx >> (rx_wlen - 16);
388 				if (rx_wlen >= 24)
389 					*rxp++ = rx >> (rx_wlen - 24);
390 				if (rx_wlen >= 32)
391 					*rxp++ = rx;
392 			}
393 			break;
394 		case 2:
395 			*((u16 *)rxbuf) = readw(qspi->base + QSPI_SPI_DATA_REG);
396 			break;
397 		case 4:
398 			*((u32 *)rxbuf) = readl(qspi->base + QSPI_SPI_DATA_REG);
399 			break;
400 		}
401 		rxbuf += rxlen;
402 		count -= rxlen;
403 	}
404 
405 	return 0;
406 }
407 
qspi_transfer_msg(struct ti_qspi * qspi,struct spi_transfer * t,int count)408 static int qspi_transfer_msg(struct ti_qspi *qspi, struct spi_transfer *t,
409 			     int count)
410 {
411 	int ret;
412 
413 	if (t->tx_buf) {
414 		ret = qspi_write_msg(qspi, t, count);
415 		if (ret) {
416 			dev_dbg(qspi->dev, "Error while writing\n");
417 			return ret;
418 		}
419 	}
420 
421 	if (t->rx_buf) {
422 		ret = qspi_read_msg(qspi, t, count);
423 		if (ret) {
424 			dev_dbg(qspi->dev, "Error while reading\n");
425 			return ret;
426 		}
427 	}
428 
429 	return 0;
430 }
431 
ti_qspi_dma_callback(void * param)432 static void ti_qspi_dma_callback(void *param)
433 {
434 	struct ti_qspi *qspi = param;
435 
436 	complete(&qspi->transfer_complete);
437 }
438 
ti_qspi_dma_xfer(struct ti_qspi * qspi,dma_addr_t dma_dst,dma_addr_t dma_src,size_t len)439 static int ti_qspi_dma_xfer(struct ti_qspi *qspi, dma_addr_t dma_dst,
440 			    dma_addr_t dma_src, size_t len)
441 {
442 	struct dma_chan *chan = qspi->rx_chan;
443 	dma_cookie_t cookie;
444 	enum dma_ctrl_flags flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
445 	struct dma_async_tx_descriptor *tx;
446 	int ret;
447 	unsigned long time_left;
448 
449 	tx = dmaengine_prep_dma_memcpy(chan, dma_dst, dma_src, len, flags);
450 	if (!tx) {
451 		dev_err(qspi->dev, "device_prep_dma_memcpy error\n");
452 		return -EIO;
453 	}
454 
455 	tx->callback = ti_qspi_dma_callback;
456 	tx->callback_param = qspi;
457 	cookie = tx->tx_submit(tx);
458 	reinit_completion(&qspi->transfer_complete);
459 
460 	ret = dma_submit_error(cookie);
461 	if (ret) {
462 		dev_err(qspi->dev, "dma_submit_error %d\n", cookie);
463 		return -EIO;
464 	}
465 
466 	dma_async_issue_pending(chan);
467 	time_left = wait_for_completion_timeout(&qspi->transfer_complete,
468 					  msecs_to_jiffies(len));
469 	if (time_left == 0) {
470 		dmaengine_terminate_sync(chan);
471 		dev_err(qspi->dev, "DMA wait_for_completion_timeout\n");
472 		return -ETIMEDOUT;
473 	}
474 
475 	return 0;
476 }
477 
ti_qspi_dma_bounce_buffer(struct ti_qspi * qspi,loff_t offs,void * to,size_t readsize)478 static int ti_qspi_dma_bounce_buffer(struct ti_qspi *qspi, loff_t offs,
479 				     void *to, size_t readsize)
480 {
481 	dma_addr_t dma_src = qspi->mmap_phys_base + offs;
482 	int ret = 0;
483 
484 	/*
485 	 * Use bounce buffer as FS like jffs2, ubifs may pass
486 	 * buffers that does not belong to kernel lowmem region.
487 	 */
488 	while (readsize != 0) {
489 		size_t xfer_len = min_t(size_t, QSPI_DMA_BUFFER_SIZE,
490 					readsize);
491 
492 		ret = ti_qspi_dma_xfer(qspi, qspi->rx_bb_dma_addr,
493 				       dma_src, xfer_len);
494 		if (ret != 0)
495 			return ret;
496 		memcpy(to, qspi->rx_bb_addr, xfer_len);
497 		readsize -= xfer_len;
498 		dma_src += xfer_len;
499 		to += xfer_len;
500 	}
501 
502 	return ret;
503 }
504 
ti_qspi_dma_xfer_sg(struct ti_qspi * qspi,struct sg_table rx_sg,loff_t from)505 static int ti_qspi_dma_xfer_sg(struct ti_qspi *qspi, struct sg_table rx_sg,
506 			       loff_t from)
507 {
508 	struct scatterlist *sg;
509 	dma_addr_t dma_src = qspi->mmap_phys_base + from;
510 	dma_addr_t dma_dst;
511 	int i, len, ret;
512 
513 	for_each_sg(rx_sg.sgl, sg, rx_sg.nents, i) {
514 		dma_dst = sg_dma_address(sg);
515 		len = sg_dma_len(sg);
516 		ret = ti_qspi_dma_xfer(qspi, dma_dst, dma_src, len);
517 		if (ret)
518 			return ret;
519 		dma_src += len;
520 	}
521 
522 	return 0;
523 }
524 
ti_qspi_enable_memory_map(struct spi_device * spi)525 static void ti_qspi_enable_memory_map(struct spi_device *spi)
526 {
527 	struct ti_qspi  *qspi = spi_controller_get_devdata(spi->controller);
528 
529 	ti_qspi_write(qspi, MM_SWITCH, QSPI_SPI_SWITCH_REG);
530 	if (qspi->ctrl_base) {
531 		regmap_update_bits(qspi->ctrl_base, qspi->ctrl_reg,
532 				   MEM_CS_MASK,
533 				   MEM_CS_EN(spi_get_chipselect(spi, 0)));
534 	}
535 	qspi->mmap_enabled = true;
536 	qspi->current_cs = spi_get_chipselect(spi, 0);
537 }
538 
ti_qspi_disable_memory_map(struct spi_device * spi)539 static void ti_qspi_disable_memory_map(struct spi_device *spi)
540 {
541 	struct ti_qspi  *qspi = spi_controller_get_devdata(spi->controller);
542 
543 	ti_qspi_write(qspi, 0, QSPI_SPI_SWITCH_REG);
544 	if (qspi->ctrl_base)
545 		regmap_update_bits(qspi->ctrl_base, qspi->ctrl_reg,
546 				   MEM_CS_MASK, 0);
547 	qspi->mmap_enabled = false;
548 	qspi->current_cs = -1;
549 }
550 
ti_qspi_setup_mmap_read(struct spi_device * spi,u8 opcode,u8 data_nbits,u8 addr_width,u8 dummy_bytes)551 static void ti_qspi_setup_mmap_read(struct spi_device *spi, u8 opcode,
552 				    u8 data_nbits, u8 addr_width,
553 				    u8 dummy_bytes)
554 {
555 	struct ti_qspi  *qspi = spi_controller_get_devdata(spi->controller);
556 	u32 memval = opcode;
557 
558 	switch (data_nbits) {
559 	case SPI_NBITS_QUAD:
560 		memval |= QSPI_SETUP_RD_QUAD;
561 		break;
562 	case SPI_NBITS_DUAL:
563 		memval |= QSPI_SETUP_RD_DUAL;
564 		break;
565 	default:
566 		memval |= QSPI_SETUP_RD_NORMAL;
567 		break;
568 	}
569 	memval |= ((addr_width - 1) << QSPI_SETUP_ADDR_SHIFT |
570 		   dummy_bytes << QSPI_SETUP_DUMMY_SHIFT);
571 	ti_qspi_write(qspi, memval,
572 		      QSPI_SPI_SETUP_REG(spi_get_chipselect(spi, 0)));
573 }
574 
ti_qspi_adjust_op_size(struct spi_mem * mem,struct spi_mem_op * op)575 static int ti_qspi_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op)
576 {
577 	struct ti_qspi *qspi = spi_controller_get_devdata(mem->spi->controller);
578 	size_t max_len;
579 
580 	if (op->data.dir == SPI_MEM_DATA_IN) {
581 		if (op->addr.val < qspi->mmap_size) {
582 			/* Limit MMIO to the mmaped region */
583 			if (op->addr.val + op->data.nbytes > qspi->mmap_size) {
584 				max_len = qspi->mmap_size - op->addr.val;
585 				op->data.nbytes = min((size_t) op->data.nbytes,
586 						      max_len);
587 			}
588 		} else {
589 			/*
590 			 * Use fallback mode (SW generated transfers) above the
591 			 * mmaped region.
592 			 * Adjust size to comply with the QSPI max frame length.
593 			 */
594 			max_len = QSPI_FRAME;
595 			max_len -= 1 + op->addr.nbytes + op->dummy.nbytes;
596 			op->data.nbytes = min((size_t) op->data.nbytes,
597 					      max_len);
598 		}
599 	}
600 
601 	return 0;
602 }
603 
ti_qspi_exec_mem_op(struct spi_mem * mem,const struct spi_mem_op * op)604 static int ti_qspi_exec_mem_op(struct spi_mem *mem,
605 			       const struct spi_mem_op *op)
606 {
607 	struct ti_qspi *qspi = spi_controller_get_devdata(mem->spi->controller);
608 	u32 from = 0;
609 	int ret = 0;
610 
611 	/* Only optimize read path. */
612 	if (!op->data.nbytes || op->data.dir != SPI_MEM_DATA_IN ||
613 	    !op->addr.nbytes || op->addr.nbytes > 4)
614 		return -EOPNOTSUPP;
615 
616 	/* Address exceeds MMIO window size, fall back to regular mode. */
617 	from = op->addr.val;
618 	if (from + op->data.nbytes > qspi->mmap_size)
619 		return -EOPNOTSUPP;
620 
621 	mutex_lock(&qspi->list_lock);
622 
623 	if (!qspi->mmap_enabled || qspi->current_cs != spi_get_chipselect(mem->spi, 0)) {
624 		ti_qspi_setup_clk(qspi, op->max_freq);
625 		ti_qspi_enable_memory_map(mem->spi);
626 	}
627 	ti_qspi_setup_mmap_read(mem->spi, op->cmd.opcode, op->data.buswidth,
628 				op->addr.nbytes, op->dummy.nbytes);
629 
630 	if (qspi->rx_chan) {
631 		struct sg_table sgt;
632 
633 		if (virt_addr_valid(op->data.buf.in) &&
634 		    !spi_controller_dma_map_mem_op_data(mem->spi->controller, op,
635 							&sgt)) {
636 			ret = ti_qspi_dma_xfer_sg(qspi, sgt, from);
637 			spi_controller_dma_unmap_mem_op_data(mem->spi->controller,
638 							     op, &sgt);
639 		} else {
640 			ret = ti_qspi_dma_bounce_buffer(qspi, from,
641 							op->data.buf.in,
642 							op->data.nbytes);
643 		}
644 	} else {
645 		memcpy_fromio(op->data.buf.in, qspi->mmap_base + from,
646 			      op->data.nbytes);
647 	}
648 
649 	mutex_unlock(&qspi->list_lock);
650 
651 	return ret;
652 }
653 
654 static const struct spi_controller_mem_ops ti_qspi_mem_ops = {
655 	.exec_op = ti_qspi_exec_mem_op,
656 	.adjust_op_size = ti_qspi_adjust_op_size,
657 };
658 
659 static const struct spi_controller_mem_caps ti_qspi_mem_caps = {
660 	.per_op_freq = true,
661 };
662 
ti_qspi_start_transfer_one(struct spi_controller * host,struct spi_message * m)663 static int ti_qspi_start_transfer_one(struct spi_controller *host,
664 		struct spi_message *m)
665 {
666 	struct ti_qspi *qspi = spi_controller_get_devdata(host);
667 	struct spi_device *spi = m->spi;
668 	struct spi_transfer *t;
669 	int status = 0, ret;
670 	unsigned int frame_len_words, transfer_len_words;
671 	int wlen;
672 
673 	/* setup device control reg */
674 	qspi->dc = 0;
675 
676 	if (spi->mode & SPI_CPHA)
677 		qspi->dc |= QSPI_CKPHA(spi_get_chipselect(spi, 0));
678 	if (spi->mode & SPI_CPOL)
679 		qspi->dc |= QSPI_CKPOL(spi_get_chipselect(spi, 0));
680 	if (spi->mode & SPI_CS_HIGH)
681 		qspi->dc |= QSPI_CSPOL(spi_get_chipselect(spi, 0));
682 
683 	frame_len_words = 0;
684 	list_for_each_entry(t, &m->transfers, transfer_list)
685 		frame_len_words += t->len / (t->bits_per_word >> 3);
686 	frame_len_words = min_t(unsigned int, frame_len_words, QSPI_FRAME);
687 
688 	/* setup command reg */
689 	qspi->cmd = 0;
690 	qspi->cmd |= QSPI_EN_CS(spi_get_chipselect(spi, 0));
691 	qspi->cmd |= QSPI_FLEN(frame_len_words);
692 
693 	ti_qspi_write(qspi, qspi->dc, QSPI_SPI_DC_REG);
694 
695 	mutex_lock(&qspi->list_lock);
696 
697 	if (qspi->mmap_enabled)
698 		ti_qspi_disable_memory_map(spi);
699 
700 	list_for_each_entry(t, &m->transfers, transfer_list) {
701 		qspi->cmd = ((qspi->cmd & ~QSPI_WLEN_MASK) |
702 			     QSPI_WLEN(t->bits_per_word));
703 
704 		wlen = t->bits_per_word >> 3;
705 		transfer_len_words = min(t->len / wlen, frame_len_words);
706 
707 		ti_qspi_setup_clk(qspi, t->speed_hz);
708 		ret = qspi_transfer_msg(qspi, t, transfer_len_words * wlen);
709 		if (ret) {
710 			dev_dbg(qspi->dev, "transfer message failed\n");
711 			mutex_unlock(&qspi->list_lock);
712 			return -EINVAL;
713 		}
714 
715 		m->actual_length += transfer_len_words * wlen;
716 		frame_len_words -= transfer_len_words;
717 		if (frame_len_words == 0)
718 			break;
719 	}
720 
721 	mutex_unlock(&qspi->list_lock);
722 
723 	ti_qspi_write(qspi, qspi->cmd | QSPI_INVAL, QSPI_SPI_CMD_REG);
724 	m->status = status;
725 	spi_finalize_current_message(host);
726 
727 	return status;
728 }
729 
ti_qspi_runtime_resume(struct device * dev)730 static int ti_qspi_runtime_resume(struct device *dev)
731 {
732 	struct ti_qspi      *qspi;
733 
734 	qspi = dev_get_drvdata(dev);
735 	ti_qspi_restore_ctx(qspi);
736 
737 	return 0;
738 }
739 
ti_qspi_dma_cleanup(struct ti_qspi * qspi)740 static void ti_qspi_dma_cleanup(struct ti_qspi *qspi)
741 {
742 	if (qspi->rx_bb_addr)
743 		dma_free_coherent(qspi->dev, QSPI_DMA_BUFFER_SIZE,
744 				  qspi->rx_bb_addr,
745 				  qspi->rx_bb_dma_addr);
746 
747 	if (qspi->rx_chan)
748 		dma_release_channel(qspi->rx_chan);
749 }
750 
751 static const struct of_device_id ti_qspi_match[] = {
752 	{.compatible = "ti,dra7xxx-qspi" },
753 	{.compatible = "ti,am4372-qspi" },
754 	{},
755 };
756 MODULE_DEVICE_TABLE(of, ti_qspi_match);
757 
ti_qspi_probe(struct platform_device * pdev)758 static int ti_qspi_probe(struct platform_device *pdev)
759 {
760 	struct  ti_qspi *qspi;
761 	struct spi_controller *host;
762 	struct resource         *r, *res_mmap;
763 	struct device_node *np = pdev->dev.of_node;
764 	u32 max_freq;
765 	int ret = 0, num_cs, irq;
766 	dma_cap_mask_t mask;
767 
768 	host = spi_alloc_host(&pdev->dev, sizeof(*qspi));
769 	if (!host)
770 		return -ENOMEM;
771 
772 	host->mode_bits = SPI_CPOL | SPI_CPHA | SPI_RX_DUAL | SPI_RX_QUAD;
773 
774 	host->flags = SPI_CONTROLLER_HALF_DUPLEX;
775 	host->setup = ti_qspi_setup;
776 	host->auto_runtime_pm = true;
777 	host->transfer_one_message = ti_qspi_start_transfer_one;
778 	host->dev.of_node = pdev->dev.of_node;
779 	host->bits_per_word_mask = SPI_BPW_MASK(32) | SPI_BPW_MASK(16) |
780 				   SPI_BPW_MASK(8);
781 	host->mem_ops = &ti_qspi_mem_ops;
782 	host->mem_caps = &ti_qspi_mem_caps;
783 
784 	if (!of_property_read_u32(np, "num-cs", &num_cs))
785 		host->num_chipselect = num_cs;
786 
787 	qspi = spi_controller_get_devdata(host);
788 	qspi->host = host;
789 	qspi->dev = &pdev->dev;
790 	platform_set_drvdata(pdev, qspi);
791 
792 	r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "qspi_base");
793 	if (r == NULL) {
794 		r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
795 		if (r == NULL) {
796 			dev_err(&pdev->dev, "missing platform data\n");
797 			ret = -ENODEV;
798 			goto free_host;
799 		}
800 	}
801 
802 	res_mmap = platform_get_resource_byname(pdev,
803 			IORESOURCE_MEM, "qspi_mmap");
804 	if (res_mmap == NULL) {
805 		res_mmap = platform_get_resource(pdev, IORESOURCE_MEM, 1);
806 		if (res_mmap == NULL) {
807 			dev_err(&pdev->dev,
808 				"memory mapped resource not required\n");
809 		}
810 	}
811 
812 	if (res_mmap)
813 		qspi->mmap_size = resource_size(res_mmap);
814 
815 	irq = platform_get_irq(pdev, 0);
816 	if (irq < 0) {
817 		ret = irq;
818 		goto free_host;
819 	}
820 
821 	mutex_init(&qspi->list_lock);
822 
823 	qspi->base = devm_ioremap_resource(&pdev->dev, r);
824 	if (IS_ERR(qspi->base)) {
825 		ret = PTR_ERR(qspi->base);
826 		goto free_host;
827 	}
828 
829 
830 	if (of_property_present(np, "syscon-chipselects")) {
831 		qspi->ctrl_base =
832 			syscon_regmap_lookup_by_phandle_args(np, "syscon-chipselects",
833 							     1, &qspi->ctrl_reg);
834 		if (IS_ERR(qspi->ctrl_base)) {
835 			ret = PTR_ERR(qspi->ctrl_base);
836 			goto free_host;
837 		}
838 	}
839 
840 	qspi->fclk = devm_clk_get(&pdev->dev, "fck");
841 	if (IS_ERR(qspi->fclk)) {
842 		ret = PTR_ERR(qspi->fclk);
843 		dev_err(&pdev->dev, "could not get clk: %d\n", ret);
844 	}
845 
846 	pm_runtime_use_autosuspend(&pdev->dev);
847 	pm_runtime_set_autosuspend_delay(&pdev->dev, QSPI_AUTOSUSPEND_TIMEOUT);
848 	pm_runtime_enable(&pdev->dev);
849 
850 	if (!of_property_read_u32(np, "spi-max-frequency", &max_freq))
851 		host->max_speed_hz = max_freq;
852 
853 	dma_cap_zero(mask);
854 	dma_cap_set(DMA_MEMCPY, mask);
855 
856 	qspi->rx_chan = dma_request_chan_by_mask(&mask);
857 	if (IS_ERR(qspi->rx_chan)) {
858 		dev_err(qspi->dev,
859 			"No Rx DMA available, trying mmap mode\n");
860 		qspi->rx_chan = NULL;
861 		goto no_dma;
862 	}
863 	qspi->rx_bb_addr = dma_alloc_coherent(qspi->dev,
864 					      QSPI_DMA_BUFFER_SIZE,
865 					      &qspi->rx_bb_dma_addr,
866 					      GFP_KERNEL | GFP_DMA);
867 	if (!qspi->rx_bb_addr) {
868 		dev_err(qspi->dev,
869 			"dma_alloc_coherent failed, using PIO mode\n");
870 		dma_release_channel(qspi->rx_chan);
871 		goto no_dma;
872 	}
873 	host->dma_rx = qspi->rx_chan;
874 	init_completion(&qspi->transfer_complete);
875 	if (res_mmap)
876 		qspi->mmap_phys_base = (dma_addr_t)res_mmap->start;
877 
878 no_dma:
879 	if (!qspi->rx_chan && res_mmap) {
880 		qspi->mmap_base = devm_ioremap_resource(&pdev->dev, res_mmap);
881 		if (IS_ERR(qspi->mmap_base)) {
882 			dev_info(&pdev->dev,
883 				 "mmap failed with error %ld using PIO mode\n",
884 				 PTR_ERR(qspi->mmap_base));
885 			qspi->mmap_base = NULL;
886 			host->mem_ops = NULL;
887 		}
888 	}
889 	qspi->mmap_enabled = false;
890 	qspi->current_cs = -1;
891 
892 	ret = devm_spi_register_controller(&pdev->dev, host);
893 	if (!ret)
894 		return 0;
895 
896 	ti_qspi_dma_cleanup(qspi);
897 
898 	pm_runtime_disable(&pdev->dev);
899 free_host:
900 	spi_controller_put(host);
901 	return ret;
902 }
903 
ti_qspi_remove(struct platform_device * pdev)904 static void ti_qspi_remove(struct platform_device *pdev)
905 {
906 	struct ti_qspi *qspi = platform_get_drvdata(pdev);
907 	int rc;
908 
909 	rc = spi_controller_suspend(qspi->host);
910 	if (rc) {
911 		dev_alert(&pdev->dev, "spi_controller_suspend() failed (%pe)\n",
912 			  ERR_PTR(rc));
913 		return;
914 	}
915 
916 	pm_runtime_put_sync(&pdev->dev);
917 	pm_runtime_disable(&pdev->dev);
918 
919 	ti_qspi_dma_cleanup(qspi);
920 }
921 
922 static const struct dev_pm_ops ti_qspi_pm_ops = {
923 	.runtime_resume = ti_qspi_runtime_resume,
924 };
925 
926 static struct platform_driver ti_qspi_driver = {
927 	.probe	= ti_qspi_probe,
928 	.remove = ti_qspi_remove,
929 	.driver = {
930 		.name	= "ti-qspi",
931 		.pm =   &ti_qspi_pm_ops,
932 		.of_match_table = ti_qspi_match,
933 	}
934 };
935 
936 module_platform_driver(ti_qspi_driver);
937 
938 MODULE_AUTHOR("Sourav Poddar <sourav.poddar@ti.com>");
939 MODULE_LICENSE("GPL v2");
940 MODULE_DESCRIPTION("TI QSPI controller driver");
941 MODULE_ALIAS("platform:ti-qspi");
942