• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
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/of_device.h>
26 #include <linux/pinctrl/consumer.h>
27 #include <linux/mfd/syscon.h>
28 #include <linux/regmap.h>
29 #include <linux/sizes.h>
30 
31 #include <linux/spi/spi.h>
32 #include <linux/spi/spi-mem.h>
33 
34 struct ti_qspi_regs {
35 	u32 clkctrl;
36 };
37 
38 struct ti_qspi {
39 	struct completion	transfer_complete;
40 
41 	/* list synchronization */
42 	struct mutex            list_lock;
43 
44 	struct spi_master	*master;
45 	void __iomem            *base;
46 	void __iomem            *mmap_base;
47 	size_t			mmap_size;
48 	struct regmap		*ctrl_base;
49 	unsigned int		ctrl_reg;
50 	struct clk		*fclk;
51 	struct device           *dev;
52 
53 	struct ti_qspi_regs     ctx_reg;
54 
55 	dma_addr_t		mmap_phys_base;
56 	dma_addr_t		rx_bb_dma_addr;
57 	void			*rx_bb_addr;
58 	struct dma_chan		*rx_chan;
59 
60 	u32 spi_max_frequency;
61 	u32 cmd;
62 	u32 dc;
63 
64 	bool mmap_enabled;
65 	int current_cs;
66 };
67 
68 #define QSPI_PID			(0x0)
69 #define QSPI_SYSCONFIG			(0x10)
70 #define QSPI_SPI_CLOCK_CNTRL_REG	(0x40)
71 #define QSPI_SPI_DC_REG			(0x44)
72 #define QSPI_SPI_CMD_REG		(0x48)
73 #define QSPI_SPI_STATUS_REG		(0x4c)
74 #define QSPI_SPI_DATA_REG		(0x50)
75 #define QSPI_SPI_SETUP_REG(n)		((0x54 + 4 * n))
76 #define QSPI_SPI_SWITCH_REG		(0x64)
77 #define QSPI_SPI_DATA_REG_1		(0x68)
78 #define QSPI_SPI_DATA_REG_2		(0x6c)
79 #define QSPI_SPI_DATA_REG_3		(0x70)
80 
81 #define QSPI_COMPLETION_TIMEOUT		msecs_to_jiffies(2000)
82 
83 /* Clock Control */
84 #define QSPI_CLK_EN			(1 << 31)
85 #define QSPI_CLK_DIV_MAX		0xffff
86 
87 /* Command */
88 #define QSPI_EN_CS(n)			(n << 28)
89 #define QSPI_WLEN(n)			((n - 1) << 19)
90 #define QSPI_3_PIN			(1 << 18)
91 #define QSPI_RD_SNGL			(1 << 16)
92 #define QSPI_WR_SNGL			(2 << 16)
93 #define QSPI_RD_DUAL			(3 << 16)
94 #define QSPI_RD_QUAD			(7 << 16)
95 #define QSPI_INVAL			(4 << 16)
96 #define QSPI_FLEN(n)			((n - 1) << 0)
97 #define QSPI_WLEN_MAX_BITS		128
98 #define QSPI_WLEN_MAX_BYTES		16
99 #define QSPI_WLEN_MASK			QSPI_WLEN(QSPI_WLEN_MAX_BITS)
100 
101 /* STATUS REGISTER */
102 #define BUSY				0x01
103 #define WC				0x02
104 
105 /* Device Control */
106 #define QSPI_DD(m, n)			(m << (3 + n * 8))
107 #define QSPI_CKPHA(n)			(1 << (2 + n * 8))
108 #define QSPI_CSPOL(n)			(1 << (1 + n * 8))
109 #define QSPI_CKPOL(n)			(1 << (n * 8))
110 
111 #define	QSPI_FRAME			4096
112 
113 #define QSPI_AUTOSUSPEND_TIMEOUT         2000
114 
115 #define MEM_CS_EN(n)			((n + 1) << 8)
116 #define MEM_CS_MASK			(7 << 8)
117 
118 #define MM_SWITCH			0x1
119 
120 #define QSPI_SETUP_RD_NORMAL		(0x0 << 12)
121 #define QSPI_SETUP_RD_DUAL		(0x1 << 12)
122 #define QSPI_SETUP_RD_QUAD		(0x3 << 12)
123 #define QSPI_SETUP_ADDR_SHIFT		8
124 #define QSPI_SETUP_DUMMY_SHIFT		10
125 
126 #define QSPI_DMA_BUFFER_SIZE            SZ_64K
127 
ti_qspi_read(struct ti_qspi * qspi,unsigned long reg)128 static inline unsigned long ti_qspi_read(struct ti_qspi *qspi,
129 		unsigned long reg)
130 {
131 	return readl(qspi->base + reg);
132 }
133 
ti_qspi_write(struct ti_qspi * qspi,unsigned long val,unsigned long reg)134 static inline void ti_qspi_write(struct ti_qspi *qspi,
135 		unsigned long val, unsigned long reg)
136 {
137 	writel(val, qspi->base + reg);
138 }
139 
ti_qspi_setup(struct spi_device * spi)140 static int ti_qspi_setup(struct spi_device *spi)
141 {
142 	struct ti_qspi	*qspi = spi_master_get_devdata(spi->master);
143 	struct ti_qspi_regs *ctx_reg = &qspi->ctx_reg;
144 	int clk_div = 0, ret;
145 	u32 clk_ctrl_reg, clk_rate, clk_mask;
146 
147 	if (spi->master->busy) {
148 		dev_dbg(qspi->dev, "master busy doing other transfers\n");
149 		return -EBUSY;
150 	}
151 
152 	if (!qspi->spi_max_frequency) {
153 		dev_err(qspi->dev, "spi max frequency not defined\n");
154 		return -EINVAL;
155 	}
156 
157 	clk_rate = clk_get_rate(qspi->fclk);
158 
159 	clk_div = DIV_ROUND_UP(clk_rate, qspi->spi_max_frequency) - 1;
160 
161 	if (clk_div < 0) {
162 		dev_dbg(qspi->dev, "clock divider < 0, using /1 divider\n");
163 		return -EINVAL;
164 	}
165 
166 	if (clk_div > QSPI_CLK_DIV_MAX) {
167 		dev_dbg(qspi->dev, "clock divider >%d , using /%d divider\n",
168 				QSPI_CLK_DIV_MAX, QSPI_CLK_DIV_MAX + 1);
169 		return -EINVAL;
170 	}
171 
172 	dev_dbg(qspi->dev, "hz: %d, clock divider %d\n",
173 			qspi->spi_max_frequency, clk_div);
174 
175 	ret = pm_runtime_get_sync(qspi->dev);
176 	if (ret < 0) {
177 		pm_runtime_put_noidle(qspi->dev);
178 		dev_err(qspi->dev, "pm_runtime_get_sync() failed\n");
179 		return ret;
180 	}
181 
182 	clk_ctrl_reg = ti_qspi_read(qspi, QSPI_SPI_CLOCK_CNTRL_REG);
183 
184 	clk_ctrl_reg &= ~QSPI_CLK_EN;
185 
186 	/* disable SCLK */
187 	ti_qspi_write(qspi, clk_ctrl_reg, QSPI_SPI_CLOCK_CNTRL_REG);
188 
189 	/* enable SCLK */
190 	clk_mask = QSPI_CLK_EN | clk_div;
191 	ti_qspi_write(qspi, clk_mask, QSPI_SPI_CLOCK_CNTRL_REG);
192 	ctx_reg->clkctrl = clk_mask;
193 
194 	pm_runtime_mark_last_busy(qspi->dev);
195 	ret = pm_runtime_put_autosuspend(qspi->dev);
196 	if (ret < 0) {
197 		dev_err(qspi->dev, "pm_runtime_put_autosuspend() failed\n");
198 		return ret;
199 	}
200 
201 	return 0;
202 }
203 
ti_qspi_restore_ctx(struct ti_qspi * qspi)204 static void ti_qspi_restore_ctx(struct ti_qspi *qspi)
205 {
206 	struct ti_qspi_regs *ctx_reg = &qspi->ctx_reg;
207 
208 	ti_qspi_write(qspi, ctx_reg->clkctrl, QSPI_SPI_CLOCK_CNTRL_REG);
209 }
210 
qspi_is_busy(struct ti_qspi * qspi)211 static inline u32 qspi_is_busy(struct ti_qspi *qspi)
212 {
213 	u32 stat;
214 	unsigned long timeout = jiffies + QSPI_COMPLETION_TIMEOUT;
215 
216 	stat = ti_qspi_read(qspi, QSPI_SPI_STATUS_REG);
217 	while ((stat & BUSY) && time_after(timeout, jiffies)) {
218 		cpu_relax();
219 		stat = ti_qspi_read(qspi, QSPI_SPI_STATUS_REG);
220 	}
221 
222 	WARN(stat & BUSY, "qspi busy\n");
223 	return stat & BUSY;
224 }
225 
ti_qspi_poll_wc(struct ti_qspi * qspi)226 static inline int ti_qspi_poll_wc(struct ti_qspi *qspi)
227 {
228 	u32 stat;
229 	unsigned long timeout = jiffies + QSPI_COMPLETION_TIMEOUT;
230 
231 	do {
232 		stat = ti_qspi_read(qspi, QSPI_SPI_STATUS_REG);
233 		if (stat & WC)
234 			return 0;
235 		cpu_relax();
236 	} while (time_after(timeout, jiffies));
237 
238 	stat = ti_qspi_read(qspi, QSPI_SPI_STATUS_REG);
239 	if (stat & WC)
240 		return 0;
241 	return  -ETIMEDOUT;
242 }
243 
qspi_write_msg(struct ti_qspi * qspi,struct spi_transfer * t,int count)244 static int qspi_write_msg(struct ti_qspi *qspi, struct spi_transfer *t,
245 			  int count)
246 {
247 	int wlen, xfer_len;
248 	unsigned int cmd;
249 	const u8 *txbuf;
250 	u32 data;
251 
252 	txbuf = t->tx_buf;
253 	cmd = qspi->cmd | QSPI_WR_SNGL;
254 	wlen = t->bits_per_word >> 3;	/* in bytes */
255 	xfer_len = wlen;
256 
257 	while (count) {
258 		if (qspi_is_busy(qspi))
259 			return -EBUSY;
260 
261 		switch (wlen) {
262 		case 1:
263 			dev_dbg(qspi->dev, "tx cmd %08x dc %08x data %02x\n",
264 					cmd, qspi->dc, *txbuf);
265 			if (count >= QSPI_WLEN_MAX_BYTES) {
266 				u32 *txp = (u32 *)txbuf;
267 
268 				data = cpu_to_be32(*txp++);
269 				writel(data, qspi->base +
270 				       QSPI_SPI_DATA_REG_3);
271 				data = cpu_to_be32(*txp++);
272 				writel(data, qspi->base +
273 				       QSPI_SPI_DATA_REG_2);
274 				data = cpu_to_be32(*txp++);
275 				writel(data, qspi->base +
276 				       QSPI_SPI_DATA_REG_1);
277 				data = cpu_to_be32(*txp++);
278 				writel(data, qspi->base +
279 				       QSPI_SPI_DATA_REG);
280 				xfer_len = QSPI_WLEN_MAX_BYTES;
281 				cmd |= QSPI_WLEN(QSPI_WLEN_MAX_BITS);
282 			} else {
283 				writeb(*txbuf, qspi->base + QSPI_SPI_DATA_REG);
284 				cmd = qspi->cmd | QSPI_WR_SNGL;
285 				xfer_len = wlen;
286 				cmd |= QSPI_WLEN(wlen);
287 			}
288 			break;
289 		case 2:
290 			dev_dbg(qspi->dev, "tx cmd %08x dc %08x data %04x\n",
291 					cmd, qspi->dc, *txbuf);
292 			writew(*((u16 *)txbuf), qspi->base + QSPI_SPI_DATA_REG);
293 			break;
294 		case 4:
295 			dev_dbg(qspi->dev, "tx cmd %08x dc %08x data %08x\n",
296 					cmd, qspi->dc, *txbuf);
297 			writel(*((u32 *)txbuf), qspi->base + QSPI_SPI_DATA_REG);
298 			break;
299 		}
300 
301 		ti_qspi_write(qspi, cmd, QSPI_SPI_CMD_REG);
302 		if (ti_qspi_poll_wc(qspi)) {
303 			dev_err(qspi->dev, "write timed out\n");
304 			return -ETIMEDOUT;
305 		}
306 		txbuf += xfer_len;
307 		count -= xfer_len;
308 	}
309 
310 	return 0;
311 }
312 
qspi_read_msg(struct ti_qspi * qspi,struct spi_transfer * t,int count)313 static int qspi_read_msg(struct ti_qspi *qspi, struct spi_transfer *t,
314 			 int count)
315 {
316 	int wlen;
317 	unsigned int cmd;
318 	u32 rx;
319 	u8 rxlen, rx_wlen;
320 	u8 *rxbuf;
321 
322 	rxbuf = t->rx_buf;
323 	cmd = qspi->cmd;
324 	switch (t->rx_nbits) {
325 	case SPI_NBITS_DUAL:
326 		cmd |= QSPI_RD_DUAL;
327 		break;
328 	case SPI_NBITS_QUAD:
329 		cmd |= QSPI_RD_QUAD;
330 		break;
331 	default:
332 		cmd |= QSPI_RD_SNGL;
333 		break;
334 	}
335 	wlen = t->bits_per_word >> 3;	/* in bytes */
336 	rx_wlen = wlen;
337 
338 	while (count) {
339 		dev_dbg(qspi->dev, "rx cmd %08x dc %08x\n", cmd, qspi->dc);
340 		if (qspi_is_busy(qspi))
341 			return -EBUSY;
342 
343 		switch (wlen) {
344 		case 1:
345 			/*
346 			 * Optimize the 8-bit words transfers, as used by
347 			 * the SPI flash devices.
348 			 */
349 			if (count >= QSPI_WLEN_MAX_BYTES) {
350 				rxlen = QSPI_WLEN_MAX_BYTES;
351 			} else {
352 				rxlen = min(count, 4);
353 			}
354 			rx_wlen = rxlen << 3;
355 			cmd &= ~QSPI_WLEN_MASK;
356 			cmd |= QSPI_WLEN(rx_wlen);
357 			break;
358 		default:
359 			rxlen = wlen;
360 			break;
361 		}
362 
363 		ti_qspi_write(qspi, cmd, QSPI_SPI_CMD_REG);
364 		if (ti_qspi_poll_wc(qspi)) {
365 			dev_err(qspi->dev, "read timed out\n");
366 			return -ETIMEDOUT;
367 		}
368 
369 		switch (wlen) {
370 		case 1:
371 			/*
372 			 * Optimize the 8-bit words transfers, as used by
373 			 * the SPI flash devices.
374 			 */
375 			if (count >= QSPI_WLEN_MAX_BYTES) {
376 				u32 *rxp = (u32 *) rxbuf;
377 				rx = readl(qspi->base + QSPI_SPI_DATA_REG_3);
378 				*rxp++ = be32_to_cpu(rx);
379 				rx = readl(qspi->base + QSPI_SPI_DATA_REG_2);
380 				*rxp++ = be32_to_cpu(rx);
381 				rx = readl(qspi->base + QSPI_SPI_DATA_REG_1);
382 				*rxp++ = be32_to_cpu(rx);
383 				rx = readl(qspi->base + QSPI_SPI_DATA_REG);
384 				*rxp++ = be32_to_cpu(rx);
385 			} else {
386 				u8 *rxp = rxbuf;
387 				rx = readl(qspi->base + QSPI_SPI_DATA_REG);
388 				if (rx_wlen >= 8)
389 					*rxp++ = rx >> (rx_wlen - 8);
390 				if (rx_wlen >= 16)
391 					*rxp++ = rx >> (rx_wlen - 16);
392 				if (rx_wlen >= 24)
393 					*rxp++ = rx >> (rx_wlen - 24);
394 				if (rx_wlen >= 32)
395 					*rxp++ = rx;
396 			}
397 			break;
398 		case 2:
399 			*((u16 *)rxbuf) = readw(qspi->base + QSPI_SPI_DATA_REG);
400 			break;
401 		case 4:
402 			*((u32 *)rxbuf) = readl(qspi->base + QSPI_SPI_DATA_REG);
403 			break;
404 		}
405 		rxbuf += rxlen;
406 		count -= rxlen;
407 	}
408 
409 	return 0;
410 }
411 
qspi_transfer_msg(struct ti_qspi * qspi,struct spi_transfer * t,int count)412 static int qspi_transfer_msg(struct ti_qspi *qspi, struct spi_transfer *t,
413 			     int count)
414 {
415 	int ret;
416 
417 	if (t->tx_buf) {
418 		ret = qspi_write_msg(qspi, t, count);
419 		if (ret) {
420 			dev_dbg(qspi->dev, "Error while writing\n");
421 			return ret;
422 		}
423 	}
424 
425 	if (t->rx_buf) {
426 		ret = qspi_read_msg(qspi, t, count);
427 		if (ret) {
428 			dev_dbg(qspi->dev, "Error while reading\n");
429 			return ret;
430 		}
431 	}
432 
433 	return 0;
434 }
435 
ti_qspi_dma_callback(void * param)436 static void ti_qspi_dma_callback(void *param)
437 {
438 	struct ti_qspi *qspi = param;
439 
440 	complete(&qspi->transfer_complete);
441 }
442 
ti_qspi_dma_xfer(struct ti_qspi * qspi,dma_addr_t dma_dst,dma_addr_t dma_src,size_t len)443 static int ti_qspi_dma_xfer(struct ti_qspi *qspi, dma_addr_t dma_dst,
444 			    dma_addr_t dma_src, size_t len)
445 {
446 	struct dma_chan *chan = qspi->rx_chan;
447 	dma_cookie_t cookie;
448 	enum dma_ctrl_flags flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
449 	struct dma_async_tx_descriptor *tx;
450 	int ret;
451 	unsigned long time_left;
452 
453 	tx = dmaengine_prep_dma_memcpy(chan, dma_dst, dma_src, len, flags);
454 	if (!tx) {
455 		dev_err(qspi->dev, "device_prep_dma_memcpy error\n");
456 		return -EIO;
457 	}
458 
459 	tx->callback = ti_qspi_dma_callback;
460 	tx->callback_param = qspi;
461 	cookie = tx->tx_submit(tx);
462 	reinit_completion(&qspi->transfer_complete);
463 
464 	ret = dma_submit_error(cookie);
465 	if (ret) {
466 		dev_err(qspi->dev, "dma_submit_error %d\n", cookie);
467 		return -EIO;
468 	}
469 
470 	dma_async_issue_pending(chan);
471 	time_left = wait_for_completion_timeout(&qspi->transfer_complete,
472 					  msecs_to_jiffies(len));
473 	if (time_left == 0) {
474 		dmaengine_terminate_sync(chan);
475 		dev_err(qspi->dev, "DMA wait_for_completion_timeout\n");
476 		return -ETIMEDOUT;
477 	}
478 
479 	return 0;
480 }
481 
ti_qspi_dma_bounce_buffer(struct ti_qspi * qspi,loff_t offs,void * to,size_t readsize)482 static int ti_qspi_dma_bounce_buffer(struct ti_qspi *qspi, loff_t offs,
483 				     void *to, size_t readsize)
484 {
485 	dma_addr_t dma_src = qspi->mmap_phys_base + offs;
486 	int ret = 0;
487 
488 	/*
489 	 * Use bounce buffer as FS like jffs2, ubifs may pass
490 	 * buffers that does not belong to kernel lowmem region.
491 	 */
492 	while (readsize != 0) {
493 		size_t xfer_len = min_t(size_t, QSPI_DMA_BUFFER_SIZE,
494 					readsize);
495 
496 		ret = ti_qspi_dma_xfer(qspi, qspi->rx_bb_dma_addr,
497 				       dma_src, xfer_len);
498 		if (ret != 0)
499 			return ret;
500 		memcpy(to, qspi->rx_bb_addr, xfer_len);
501 		readsize -= xfer_len;
502 		dma_src += xfer_len;
503 		to += xfer_len;
504 	}
505 
506 	return ret;
507 }
508 
ti_qspi_dma_xfer_sg(struct ti_qspi * qspi,struct sg_table rx_sg,loff_t from)509 static int ti_qspi_dma_xfer_sg(struct ti_qspi *qspi, struct sg_table rx_sg,
510 			       loff_t from)
511 {
512 	struct scatterlist *sg;
513 	dma_addr_t dma_src = qspi->mmap_phys_base + from;
514 	dma_addr_t dma_dst;
515 	int i, len, ret;
516 
517 	for_each_sg(rx_sg.sgl, sg, rx_sg.nents, i) {
518 		dma_dst = sg_dma_address(sg);
519 		len = sg_dma_len(sg);
520 		ret = ti_qspi_dma_xfer(qspi, dma_dst, dma_src, len);
521 		if (ret)
522 			return ret;
523 		dma_src += len;
524 	}
525 
526 	return 0;
527 }
528 
ti_qspi_enable_memory_map(struct spi_device * spi)529 static void ti_qspi_enable_memory_map(struct spi_device *spi)
530 {
531 	struct ti_qspi  *qspi = spi_master_get_devdata(spi->master);
532 
533 	ti_qspi_write(qspi, MM_SWITCH, QSPI_SPI_SWITCH_REG);
534 	if (qspi->ctrl_base) {
535 		regmap_update_bits(qspi->ctrl_base, qspi->ctrl_reg,
536 				   MEM_CS_MASK,
537 				   MEM_CS_EN(spi->chip_select));
538 	}
539 	qspi->mmap_enabled = true;
540 	qspi->current_cs = spi->chip_select;
541 }
542 
ti_qspi_disable_memory_map(struct spi_device * spi)543 static void ti_qspi_disable_memory_map(struct spi_device *spi)
544 {
545 	struct ti_qspi  *qspi = spi_master_get_devdata(spi->master);
546 
547 	ti_qspi_write(qspi, 0, QSPI_SPI_SWITCH_REG);
548 	if (qspi->ctrl_base)
549 		regmap_update_bits(qspi->ctrl_base, qspi->ctrl_reg,
550 				   MEM_CS_MASK, 0);
551 	qspi->mmap_enabled = false;
552 	qspi->current_cs = -1;
553 }
554 
ti_qspi_setup_mmap_read(struct spi_device * spi,u8 opcode,u8 data_nbits,u8 addr_width,u8 dummy_bytes)555 static void ti_qspi_setup_mmap_read(struct spi_device *spi, u8 opcode,
556 				    u8 data_nbits, u8 addr_width,
557 				    u8 dummy_bytes)
558 {
559 	struct ti_qspi  *qspi = spi_master_get_devdata(spi->master);
560 	u32 memval = opcode;
561 
562 	switch (data_nbits) {
563 	case SPI_NBITS_QUAD:
564 		memval |= QSPI_SETUP_RD_QUAD;
565 		break;
566 	case SPI_NBITS_DUAL:
567 		memval |= QSPI_SETUP_RD_DUAL;
568 		break;
569 	default:
570 		memval |= QSPI_SETUP_RD_NORMAL;
571 		break;
572 	}
573 	memval |= ((addr_width - 1) << QSPI_SETUP_ADDR_SHIFT |
574 		   dummy_bytes << QSPI_SETUP_DUMMY_SHIFT);
575 	ti_qspi_write(qspi, memval,
576 		      QSPI_SPI_SETUP_REG(spi->chip_select));
577 }
578 
ti_qspi_adjust_op_size(struct spi_mem * mem,struct spi_mem_op * op)579 static int ti_qspi_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op)
580 {
581 	struct ti_qspi *qspi = spi_controller_get_devdata(mem->spi->master);
582 	size_t max_len;
583 
584 	if (op->data.dir == SPI_MEM_DATA_IN) {
585 		if (op->addr.val < qspi->mmap_size) {
586 			/* Limit MMIO to the mmaped region */
587 			if (op->addr.val + op->data.nbytes > qspi->mmap_size) {
588 				max_len = qspi->mmap_size - op->addr.val;
589 				op->data.nbytes = min((size_t) op->data.nbytes,
590 						      max_len);
591 			}
592 		} else {
593 			/*
594 			 * Use fallback mode (SW generated transfers) above the
595 			 * mmaped region.
596 			 * Adjust size to comply with the QSPI max frame length.
597 			 */
598 			max_len = QSPI_FRAME;
599 			max_len -= 1 + op->addr.nbytes + op->dummy.nbytes;
600 			op->data.nbytes = min((size_t) op->data.nbytes,
601 					      max_len);
602 		}
603 	}
604 
605 	return 0;
606 }
607 
ti_qspi_exec_mem_op(struct spi_mem * mem,const struct spi_mem_op * op)608 static int ti_qspi_exec_mem_op(struct spi_mem *mem,
609 			       const struct spi_mem_op *op)
610 {
611 	struct ti_qspi *qspi = spi_master_get_devdata(mem->spi->master);
612 	u32 from = 0;
613 	int ret = 0;
614 
615 	/* Only optimize read path. */
616 	if (!op->data.nbytes || op->data.dir != SPI_MEM_DATA_IN ||
617 	    !op->addr.nbytes || op->addr.nbytes > 4)
618 		return -ENOTSUPP;
619 
620 	/* Address exceeds MMIO window size, fall back to regular mode. */
621 	from = op->addr.val;
622 	if (from + op->data.nbytes > qspi->mmap_size)
623 		return -ENOTSUPP;
624 
625 	mutex_lock(&qspi->list_lock);
626 
627 	if (!qspi->mmap_enabled || qspi->current_cs != mem->spi->chip_select)
628 		ti_qspi_enable_memory_map(mem->spi);
629 	ti_qspi_setup_mmap_read(mem->spi, op->cmd.opcode, op->data.buswidth,
630 				op->addr.nbytes, op->dummy.nbytes);
631 
632 	if (qspi->rx_chan) {
633 		struct sg_table sgt;
634 
635 		if (virt_addr_valid(op->data.buf.in) &&
636 		    !spi_controller_dma_map_mem_op_data(mem->spi->master, op,
637 							&sgt)) {
638 			ret = ti_qspi_dma_xfer_sg(qspi, sgt, from);
639 			spi_controller_dma_unmap_mem_op_data(mem->spi->master,
640 							     op, &sgt);
641 		} else {
642 			ret = ti_qspi_dma_bounce_buffer(qspi, from,
643 							op->data.buf.in,
644 							op->data.nbytes);
645 		}
646 	} else {
647 		memcpy_fromio(op->data.buf.in, qspi->mmap_base + from,
648 			      op->data.nbytes);
649 	}
650 
651 	mutex_unlock(&qspi->list_lock);
652 
653 	return ret;
654 }
655 
656 static const struct spi_controller_mem_ops ti_qspi_mem_ops = {
657 	.exec_op = ti_qspi_exec_mem_op,
658 	.adjust_op_size = ti_qspi_adjust_op_size,
659 };
660 
ti_qspi_start_transfer_one(struct spi_master * master,struct spi_message * m)661 static int ti_qspi_start_transfer_one(struct spi_master *master,
662 		struct spi_message *m)
663 {
664 	struct ti_qspi *qspi = spi_master_get_devdata(master);
665 	struct spi_device *spi = m->spi;
666 	struct spi_transfer *t;
667 	int status = 0, ret;
668 	unsigned int frame_len_words, transfer_len_words;
669 	int wlen;
670 
671 	/* setup device control reg */
672 	qspi->dc = 0;
673 
674 	if (spi->mode & SPI_CPHA)
675 		qspi->dc |= QSPI_CKPHA(spi->chip_select);
676 	if (spi->mode & SPI_CPOL)
677 		qspi->dc |= QSPI_CKPOL(spi->chip_select);
678 	if (spi->mode & SPI_CS_HIGH)
679 		qspi->dc |= QSPI_CSPOL(spi->chip_select);
680 
681 	frame_len_words = 0;
682 	list_for_each_entry(t, &m->transfers, transfer_list)
683 		frame_len_words += t->len / (t->bits_per_word >> 3);
684 	frame_len_words = min_t(unsigned int, frame_len_words, QSPI_FRAME);
685 
686 	/* setup command reg */
687 	qspi->cmd = 0;
688 	qspi->cmd |= QSPI_EN_CS(spi->chip_select);
689 	qspi->cmd |= QSPI_FLEN(frame_len_words);
690 
691 	ti_qspi_write(qspi, qspi->dc, QSPI_SPI_DC_REG);
692 
693 	mutex_lock(&qspi->list_lock);
694 
695 	if (qspi->mmap_enabled)
696 		ti_qspi_disable_memory_map(spi);
697 
698 	list_for_each_entry(t, &m->transfers, transfer_list) {
699 		qspi->cmd = ((qspi->cmd & ~QSPI_WLEN_MASK) |
700 			     QSPI_WLEN(t->bits_per_word));
701 
702 		wlen = t->bits_per_word >> 3;
703 		transfer_len_words = min(t->len / wlen, frame_len_words);
704 
705 		ret = qspi_transfer_msg(qspi, t, transfer_len_words * wlen);
706 		if (ret) {
707 			dev_dbg(qspi->dev, "transfer message failed\n");
708 			mutex_unlock(&qspi->list_lock);
709 			return -EINVAL;
710 		}
711 
712 		m->actual_length += transfer_len_words * wlen;
713 		frame_len_words -= transfer_len_words;
714 		if (frame_len_words == 0)
715 			break;
716 	}
717 
718 	mutex_unlock(&qspi->list_lock);
719 
720 	ti_qspi_write(qspi, qspi->cmd | QSPI_INVAL, QSPI_SPI_CMD_REG);
721 	m->status = status;
722 	spi_finalize_current_message(master);
723 
724 	return status;
725 }
726 
ti_qspi_runtime_resume(struct device * dev)727 static int ti_qspi_runtime_resume(struct device *dev)
728 {
729 	struct ti_qspi      *qspi;
730 
731 	qspi = dev_get_drvdata(dev);
732 	ti_qspi_restore_ctx(qspi);
733 
734 	return 0;
735 }
736 
ti_qspi_dma_cleanup(struct ti_qspi * qspi)737 static void ti_qspi_dma_cleanup(struct ti_qspi *qspi)
738 {
739 	if (qspi->rx_bb_addr)
740 		dma_free_coherent(qspi->dev, QSPI_DMA_BUFFER_SIZE,
741 				  qspi->rx_bb_addr,
742 				  qspi->rx_bb_dma_addr);
743 
744 	if (qspi->rx_chan)
745 		dma_release_channel(qspi->rx_chan);
746 }
747 
748 static const struct of_device_id ti_qspi_match[] = {
749 	{.compatible = "ti,dra7xxx-qspi" },
750 	{.compatible = "ti,am4372-qspi" },
751 	{},
752 };
753 MODULE_DEVICE_TABLE(of, ti_qspi_match);
754 
ti_qspi_probe(struct platform_device * pdev)755 static int ti_qspi_probe(struct platform_device *pdev)
756 {
757 	struct  ti_qspi *qspi;
758 	struct spi_master *master;
759 	struct resource         *r, *res_mmap;
760 	struct device_node *np = pdev->dev.of_node;
761 	u32 max_freq;
762 	int ret = 0, num_cs, irq;
763 	dma_cap_mask_t mask;
764 
765 	master = spi_alloc_master(&pdev->dev, sizeof(*qspi));
766 	if (!master)
767 		return -ENOMEM;
768 
769 	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_RX_DUAL | SPI_RX_QUAD;
770 
771 	master->flags = SPI_MASTER_HALF_DUPLEX;
772 	master->setup = ti_qspi_setup;
773 	master->auto_runtime_pm = true;
774 	master->transfer_one_message = ti_qspi_start_transfer_one;
775 	master->dev.of_node = pdev->dev.of_node;
776 	master->bits_per_word_mask = SPI_BPW_MASK(32) | SPI_BPW_MASK(16) |
777 				     SPI_BPW_MASK(8);
778 	master->mem_ops = &ti_qspi_mem_ops;
779 
780 	if (!of_property_read_u32(np, "num-cs", &num_cs))
781 		master->num_chipselect = num_cs;
782 
783 	qspi = spi_master_get_devdata(master);
784 	qspi->master = master;
785 	qspi->dev = &pdev->dev;
786 	platform_set_drvdata(pdev, qspi);
787 
788 	r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "qspi_base");
789 	if (r == NULL) {
790 		r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
791 		if (r == NULL) {
792 			dev_err(&pdev->dev, "missing platform data\n");
793 			ret = -ENODEV;
794 			goto free_master;
795 		}
796 	}
797 
798 	res_mmap = platform_get_resource_byname(pdev,
799 			IORESOURCE_MEM, "qspi_mmap");
800 	if (res_mmap == NULL) {
801 		res_mmap = platform_get_resource(pdev, IORESOURCE_MEM, 1);
802 		if (res_mmap == NULL) {
803 			dev_err(&pdev->dev,
804 				"memory mapped resource not required\n");
805 		}
806 	}
807 
808 	if (res_mmap)
809 		qspi->mmap_size = resource_size(res_mmap);
810 
811 	irq = platform_get_irq(pdev, 0);
812 	if (irq < 0) {
813 		ret = irq;
814 		goto free_master;
815 	}
816 
817 	mutex_init(&qspi->list_lock);
818 
819 	qspi->base = devm_ioremap_resource(&pdev->dev, r);
820 	if (IS_ERR(qspi->base)) {
821 		ret = PTR_ERR(qspi->base);
822 		goto free_master;
823 	}
824 
825 
826 	if (of_property_read_bool(np, "syscon-chipselects")) {
827 		qspi->ctrl_base =
828 		syscon_regmap_lookup_by_phandle(np,
829 						"syscon-chipselects");
830 		if (IS_ERR(qspi->ctrl_base)) {
831 			ret = PTR_ERR(qspi->ctrl_base);
832 			goto free_master;
833 		}
834 		ret = of_property_read_u32_index(np,
835 						 "syscon-chipselects",
836 						 1, &qspi->ctrl_reg);
837 		if (ret) {
838 			dev_err(&pdev->dev,
839 				"couldn't get ctrl_mod reg index\n");
840 			goto free_master;
841 		}
842 	}
843 
844 	qspi->fclk = devm_clk_get(&pdev->dev, "fck");
845 	if (IS_ERR(qspi->fclk)) {
846 		ret = PTR_ERR(qspi->fclk);
847 		dev_err(&pdev->dev, "could not get clk: %d\n", ret);
848 	}
849 
850 	pm_runtime_use_autosuspend(&pdev->dev);
851 	pm_runtime_set_autosuspend_delay(&pdev->dev, QSPI_AUTOSUSPEND_TIMEOUT);
852 	pm_runtime_enable(&pdev->dev);
853 
854 	if (!of_property_read_u32(np, "spi-max-frequency", &max_freq))
855 		qspi->spi_max_frequency = max_freq;
856 
857 	dma_cap_zero(mask);
858 	dma_cap_set(DMA_MEMCPY, mask);
859 
860 	qspi->rx_chan = dma_request_chan_by_mask(&mask);
861 	if (IS_ERR(qspi->rx_chan)) {
862 		dev_err(qspi->dev,
863 			"No Rx DMA available, trying mmap mode\n");
864 		qspi->rx_chan = NULL;
865 		ret = 0;
866 		goto no_dma;
867 	}
868 	qspi->rx_bb_addr = dma_alloc_coherent(qspi->dev,
869 					      QSPI_DMA_BUFFER_SIZE,
870 					      &qspi->rx_bb_dma_addr,
871 					      GFP_KERNEL | GFP_DMA);
872 	if (!qspi->rx_bb_addr) {
873 		dev_err(qspi->dev,
874 			"dma_alloc_coherent failed, using PIO mode\n");
875 		dma_release_channel(qspi->rx_chan);
876 		goto no_dma;
877 	}
878 	master->dma_rx = qspi->rx_chan;
879 	init_completion(&qspi->transfer_complete);
880 	if (res_mmap)
881 		qspi->mmap_phys_base = (dma_addr_t)res_mmap->start;
882 
883 no_dma:
884 	if (!qspi->rx_chan && res_mmap) {
885 		qspi->mmap_base = devm_ioremap_resource(&pdev->dev, res_mmap);
886 		if (IS_ERR(qspi->mmap_base)) {
887 			dev_info(&pdev->dev,
888 				 "mmap failed with error %ld using PIO mode\n",
889 				 PTR_ERR(qspi->mmap_base));
890 			qspi->mmap_base = NULL;
891 			master->mem_ops = NULL;
892 		}
893 	}
894 	qspi->mmap_enabled = false;
895 	qspi->current_cs = -1;
896 
897 	ret = devm_spi_register_master(&pdev->dev, master);
898 	if (!ret)
899 		return 0;
900 
901 	ti_qspi_dma_cleanup(qspi);
902 
903 	pm_runtime_disable(&pdev->dev);
904 free_master:
905 	spi_master_put(master);
906 	return ret;
907 }
908 
ti_qspi_remove(struct platform_device * pdev)909 static int ti_qspi_remove(struct platform_device *pdev)
910 {
911 	struct ti_qspi *qspi = platform_get_drvdata(pdev);
912 	int rc;
913 
914 	rc = spi_master_suspend(qspi->master);
915 	if (rc)
916 		return rc;
917 
918 	pm_runtime_put_sync(&pdev->dev);
919 	pm_runtime_disable(&pdev->dev);
920 
921 	ti_qspi_dma_cleanup(qspi);
922 
923 	return 0;
924 }
925 
926 static const struct dev_pm_ops ti_qspi_pm_ops = {
927 	.runtime_resume = ti_qspi_runtime_resume,
928 };
929 
930 static struct platform_driver ti_qspi_driver = {
931 	.probe	= ti_qspi_probe,
932 	.remove = ti_qspi_remove,
933 	.driver = {
934 		.name	= "ti-qspi",
935 		.pm =   &ti_qspi_pm_ops,
936 		.of_match_table = ti_qspi_match,
937 	}
938 };
939 
940 module_platform_driver(ti_qspi_driver);
941 
942 MODULE_AUTHOR("Sourav Poddar <sourav.poddar@ti.com>");
943 MODULE_LICENSE("GPL v2");
944 MODULE_DESCRIPTION("TI QSPI controller driver");
945 MODULE_ALIAS("platform:ti-qspi");
946