xref: /openbmc/linux/drivers/spi/spi-ti-qspi.c (revision c900529f3d9161bfde5cca0754f83b4d3c3e0220)
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_master	*master;
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_master_get_devdata(spi->master);
141  	int ret;
142  
143  	if (spi->master->busy) {
144  		dev_dbg(qspi->dev, "master busy doing other transfers\n");
145  		return -EBUSY;
146  	}
147  
148  	if (!qspi->master->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->master->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  	pm_runtime_mark_last_busy(qspi->dev);
162  	ret = pm_runtime_put_autosuspend(qspi->dev);
163  	if (ret < 0) {
164  		dev_err(qspi->dev, "pm_runtime_put_autosuspend() failed\n");
165  		return ret;
166  	}
167  
168  	return 0;
169  }
170  
ti_qspi_setup_clk(struct ti_qspi * qspi,u32 speed_hz)171  static void ti_qspi_setup_clk(struct ti_qspi *qspi, u32 speed_hz)
172  {
173  	struct ti_qspi_regs *ctx_reg = &qspi->ctx_reg;
174  	int clk_div;
175  	u32 clk_ctrl_reg, clk_rate, clk_ctrl_new;
176  
177  	clk_rate = clk_get_rate(qspi->fclk);
178  	clk_div = DIV_ROUND_UP(clk_rate, speed_hz) - 1;
179  	clk_div = clamp(clk_div, 0, QSPI_CLK_DIV_MAX);
180  	dev_dbg(qspi->dev, "hz: %d, clock divider %d\n", speed_hz, clk_div);
181  
182  	pm_runtime_resume_and_get(qspi->dev);
183  
184  	clk_ctrl_new = QSPI_CLK_EN | clk_div;
185  	if (ctx_reg->clkctrl != clk_ctrl_new) {
186  		clk_ctrl_reg = ti_qspi_read(qspi, QSPI_SPI_CLOCK_CNTRL_REG);
187  
188  		clk_ctrl_reg &= ~QSPI_CLK_EN;
189  
190  		/* disable SCLK */
191  		ti_qspi_write(qspi, clk_ctrl_reg, QSPI_SPI_CLOCK_CNTRL_REG);
192  
193  		/* enable SCLK */
194  		ti_qspi_write(qspi, clk_ctrl_new, QSPI_SPI_CLOCK_CNTRL_REG);
195  		ctx_reg->clkctrl = clk_ctrl_new;
196  	}
197  
198  	pm_runtime_mark_last_busy(qspi->dev);
199  	pm_runtime_put_autosuspend(qspi->dev);
200  }
201  
ti_qspi_restore_ctx(struct ti_qspi * qspi)202  static void ti_qspi_restore_ctx(struct ti_qspi *qspi)
203  {
204  	struct ti_qspi_regs *ctx_reg = &qspi->ctx_reg;
205  
206  	ti_qspi_write(qspi, ctx_reg->clkctrl, QSPI_SPI_CLOCK_CNTRL_REG);
207  }
208  
qspi_is_busy(struct ti_qspi * qspi)209  static inline u32 qspi_is_busy(struct ti_qspi *qspi)
210  {
211  	u32 stat;
212  	unsigned long timeout = jiffies + QSPI_COMPLETION_TIMEOUT;
213  
214  	stat = ti_qspi_read(qspi, QSPI_SPI_STATUS_REG);
215  	while ((stat & BUSY) && time_after(timeout, jiffies)) {
216  		cpu_relax();
217  		stat = ti_qspi_read(qspi, QSPI_SPI_STATUS_REG);
218  	}
219  
220  	WARN(stat & BUSY, "qspi busy\n");
221  	return stat & BUSY;
222  }
223  
ti_qspi_poll_wc(struct ti_qspi * qspi)224  static inline int ti_qspi_poll_wc(struct ti_qspi *qspi)
225  {
226  	u32 stat;
227  	unsigned long timeout = jiffies + QSPI_COMPLETION_TIMEOUT;
228  
229  	do {
230  		stat = ti_qspi_read(qspi, QSPI_SPI_STATUS_REG);
231  		if (stat & WC)
232  			return 0;
233  		cpu_relax();
234  	} while (time_after(timeout, jiffies));
235  
236  	stat = ti_qspi_read(qspi, QSPI_SPI_STATUS_REG);
237  	if (stat & WC)
238  		return 0;
239  	return  -ETIMEDOUT;
240  }
241  
qspi_write_msg(struct ti_qspi * qspi,struct spi_transfer * t,int count)242  static int qspi_write_msg(struct ti_qspi *qspi, struct spi_transfer *t,
243  			  int count)
244  {
245  	int wlen, xfer_len;
246  	unsigned int cmd;
247  	const u8 *txbuf;
248  	u32 data;
249  
250  	txbuf = t->tx_buf;
251  	cmd = qspi->cmd | QSPI_WR_SNGL;
252  	wlen = t->bits_per_word >> 3;	/* in bytes */
253  	xfer_len = wlen;
254  
255  	while (count) {
256  		if (qspi_is_busy(qspi))
257  			return -EBUSY;
258  
259  		switch (wlen) {
260  		case 1:
261  			dev_dbg(qspi->dev, "tx cmd %08x dc %08x data %02x\n",
262  					cmd, qspi->dc, *txbuf);
263  			if (count >= QSPI_WLEN_MAX_BYTES) {
264  				u32 *txp = (u32 *)txbuf;
265  
266  				data = cpu_to_be32(*txp++);
267  				writel(data, qspi->base +
268  				       QSPI_SPI_DATA_REG_3);
269  				data = cpu_to_be32(*txp++);
270  				writel(data, qspi->base +
271  				       QSPI_SPI_DATA_REG_2);
272  				data = cpu_to_be32(*txp++);
273  				writel(data, qspi->base +
274  				       QSPI_SPI_DATA_REG_1);
275  				data = cpu_to_be32(*txp++);
276  				writel(data, qspi->base +
277  				       QSPI_SPI_DATA_REG);
278  				xfer_len = QSPI_WLEN_MAX_BYTES;
279  				cmd |= QSPI_WLEN(QSPI_WLEN_MAX_BITS);
280  			} else {
281  				writeb(*txbuf, qspi->base + QSPI_SPI_DATA_REG);
282  				cmd = qspi->cmd | QSPI_WR_SNGL;
283  				xfer_len = wlen;
284  				cmd |= QSPI_WLEN(wlen);
285  			}
286  			break;
287  		case 2:
288  			dev_dbg(qspi->dev, "tx cmd %08x dc %08x data %04x\n",
289  					cmd, qspi->dc, *txbuf);
290  			writew(*((u16 *)txbuf), qspi->base + QSPI_SPI_DATA_REG);
291  			break;
292  		case 4:
293  			dev_dbg(qspi->dev, "tx cmd %08x dc %08x data %08x\n",
294  					cmd, qspi->dc, *txbuf);
295  			writel(*((u32 *)txbuf), qspi->base + QSPI_SPI_DATA_REG);
296  			break;
297  		}
298  
299  		ti_qspi_write(qspi, cmd, QSPI_SPI_CMD_REG);
300  		if (ti_qspi_poll_wc(qspi)) {
301  			dev_err(qspi->dev, "write timed out\n");
302  			return -ETIMEDOUT;
303  		}
304  		txbuf += xfer_len;
305  		count -= xfer_len;
306  	}
307  
308  	return 0;
309  }
310  
qspi_read_msg(struct ti_qspi * qspi,struct spi_transfer * t,int count)311  static int qspi_read_msg(struct ti_qspi *qspi, struct spi_transfer *t,
312  			 int count)
313  {
314  	int wlen;
315  	unsigned int cmd;
316  	u32 rx;
317  	u8 rxlen, rx_wlen;
318  	u8 *rxbuf;
319  
320  	rxbuf = t->rx_buf;
321  	cmd = qspi->cmd;
322  	switch (t->rx_nbits) {
323  	case SPI_NBITS_DUAL:
324  		cmd |= QSPI_RD_DUAL;
325  		break;
326  	case SPI_NBITS_QUAD:
327  		cmd |= QSPI_RD_QUAD;
328  		break;
329  	default:
330  		cmd |= QSPI_RD_SNGL;
331  		break;
332  	}
333  	wlen = t->bits_per_word >> 3;	/* in bytes */
334  	rx_wlen = wlen;
335  
336  	while (count) {
337  		dev_dbg(qspi->dev, "rx cmd %08x dc %08x\n", cmd, qspi->dc);
338  		if (qspi_is_busy(qspi))
339  			return -EBUSY;
340  
341  		switch (wlen) {
342  		case 1:
343  			/*
344  			 * Optimize the 8-bit words transfers, as used by
345  			 * the SPI flash devices.
346  			 */
347  			if (count >= QSPI_WLEN_MAX_BYTES) {
348  				rxlen = QSPI_WLEN_MAX_BYTES;
349  			} else {
350  				rxlen = min(count, 4);
351  			}
352  			rx_wlen = rxlen << 3;
353  			cmd &= ~QSPI_WLEN_MASK;
354  			cmd |= QSPI_WLEN(rx_wlen);
355  			break;
356  		default:
357  			rxlen = wlen;
358  			break;
359  		}
360  
361  		ti_qspi_write(qspi, cmd, QSPI_SPI_CMD_REG);
362  		if (ti_qspi_poll_wc(qspi)) {
363  			dev_err(qspi->dev, "read timed out\n");
364  			return -ETIMEDOUT;
365  		}
366  
367  		switch (wlen) {
368  		case 1:
369  			/*
370  			 * Optimize the 8-bit words transfers, as used by
371  			 * the SPI flash devices.
372  			 */
373  			if (count >= QSPI_WLEN_MAX_BYTES) {
374  				u32 *rxp = (u32 *) rxbuf;
375  				rx = readl(qspi->base + QSPI_SPI_DATA_REG_3);
376  				*rxp++ = be32_to_cpu(rx);
377  				rx = readl(qspi->base + QSPI_SPI_DATA_REG_2);
378  				*rxp++ = be32_to_cpu(rx);
379  				rx = readl(qspi->base + QSPI_SPI_DATA_REG_1);
380  				*rxp++ = be32_to_cpu(rx);
381  				rx = readl(qspi->base + QSPI_SPI_DATA_REG);
382  				*rxp++ = be32_to_cpu(rx);
383  			} else {
384  				u8 *rxp = rxbuf;
385  				rx = readl(qspi->base + QSPI_SPI_DATA_REG);
386  				if (rx_wlen >= 8)
387  					*rxp++ = rx >> (rx_wlen - 8);
388  				if (rx_wlen >= 16)
389  					*rxp++ = rx >> (rx_wlen - 16);
390  				if (rx_wlen >= 24)
391  					*rxp++ = rx >> (rx_wlen - 24);
392  				if (rx_wlen >= 32)
393  					*rxp++ = rx;
394  			}
395  			break;
396  		case 2:
397  			*((u16 *)rxbuf) = readw(qspi->base + QSPI_SPI_DATA_REG);
398  			break;
399  		case 4:
400  			*((u32 *)rxbuf) = readl(qspi->base + QSPI_SPI_DATA_REG);
401  			break;
402  		}
403  		rxbuf += rxlen;
404  		count -= rxlen;
405  	}
406  
407  	return 0;
408  }
409  
qspi_transfer_msg(struct ti_qspi * qspi,struct spi_transfer * t,int count)410  static int qspi_transfer_msg(struct ti_qspi *qspi, struct spi_transfer *t,
411  			     int count)
412  {
413  	int ret;
414  
415  	if (t->tx_buf) {
416  		ret = qspi_write_msg(qspi, t, count);
417  		if (ret) {
418  			dev_dbg(qspi->dev, "Error while writing\n");
419  			return ret;
420  		}
421  	}
422  
423  	if (t->rx_buf) {
424  		ret = qspi_read_msg(qspi, t, count);
425  		if (ret) {
426  			dev_dbg(qspi->dev, "Error while reading\n");
427  			return ret;
428  		}
429  	}
430  
431  	return 0;
432  }
433  
ti_qspi_dma_callback(void * param)434  static void ti_qspi_dma_callback(void *param)
435  {
436  	struct ti_qspi *qspi = param;
437  
438  	complete(&qspi->transfer_complete);
439  }
440  
ti_qspi_dma_xfer(struct ti_qspi * qspi,dma_addr_t dma_dst,dma_addr_t dma_src,size_t len)441  static int ti_qspi_dma_xfer(struct ti_qspi *qspi, dma_addr_t dma_dst,
442  			    dma_addr_t dma_src, size_t len)
443  {
444  	struct dma_chan *chan = qspi->rx_chan;
445  	dma_cookie_t cookie;
446  	enum dma_ctrl_flags flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
447  	struct dma_async_tx_descriptor *tx;
448  	int ret;
449  	unsigned long time_left;
450  
451  	tx = dmaengine_prep_dma_memcpy(chan, dma_dst, dma_src, len, flags);
452  	if (!tx) {
453  		dev_err(qspi->dev, "device_prep_dma_memcpy error\n");
454  		return -EIO;
455  	}
456  
457  	tx->callback = ti_qspi_dma_callback;
458  	tx->callback_param = qspi;
459  	cookie = tx->tx_submit(tx);
460  	reinit_completion(&qspi->transfer_complete);
461  
462  	ret = dma_submit_error(cookie);
463  	if (ret) {
464  		dev_err(qspi->dev, "dma_submit_error %d\n", cookie);
465  		return -EIO;
466  	}
467  
468  	dma_async_issue_pending(chan);
469  	time_left = wait_for_completion_timeout(&qspi->transfer_complete,
470  					  msecs_to_jiffies(len));
471  	if (time_left == 0) {
472  		dmaengine_terminate_sync(chan);
473  		dev_err(qspi->dev, "DMA wait_for_completion_timeout\n");
474  		return -ETIMEDOUT;
475  	}
476  
477  	return 0;
478  }
479  
ti_qspi_dma_bounce_buffer(struct ti_qspi * qspi,loff_t offs,void * to,size_t readsize)480  static int ti_qspi_dma_bounce_buffer(struct ti_qspi *qspi, loff_t offs,
481  				     void *to, size_t readsize)
482  {
483  	dma_addr_t dma_src = qspi->mmap_phys_base + offs;
484  	int ret = 0;
485  
486  	/*
487  	 * Use bounce buffer as FS like jffs2, ubifs may pass
488  	 * buffers that does not belong to kernel lowmem region.
489  	 */
490  	while (readsize != 0) {
491  		size_t xfer_len = min_t(size_t, QSPI_DMA_BUFFER_SIZE,
492  					readsize);
493  
494  		ret = ti_qspi_dma_xfer(qspi, qspi->rx_bb_dma_addr,
495  				       dma_src, xfer_len);
496  		if (ret != 0)
497  			return ret;
498  		memcpy(to, qspi->rx_bb_addr, xfer_len);
499  		readsize -= xfer_len;
500  		dma_src += xfer_len;
501  		to += xfer_len;
502  	}
503  
504  	return ret;
505  }
506  
ti_qspi_dma_xfer_sg(struct ti_qspi * qspi,struct sg_table rx_sg,loff_t from)507  static int ti_qspi_dma_xfer_sg(struct ti_qspi *qspi, struct sg_table rx_sg,
508  			       loff_t from)
509  {
510  	struct scatterlist *sg;
511  	dma_addr_t dma_src = qspi->mmap_phys_base + from;
512  	dma_addr_t dma_dst;
513  	int i, len, ret;
514  
515  	for_each_sg(rx_sg.sgl, sg, rx_sg.nents, i) {
516  		dma_dst = sg_dma_address(sg);
517  		len = sg_dma_len(sg);
518  		ret = ti_qspi_dma_xfer(qspi, dma_dst, dma_src, len);
519  		if (ret)
520  			return ret;
521  		dma_src += len;
522  	}
523  
524  	return 0;
525  }
526  
ti_qspi_enable_memory_map(struct spi_device * spi)527  static void ti_qspi_enable_memory_map(struct spi_device *spi)
528  {
529  	struct ti_qspi  *qspi = spi_master_get_devdata(spi->master);
530  
531  	ti_qspi_write(qspi, MM_SWITCH, QSPI_SPI_SWITCH_REG);
532  	if (qspi->ctrl_base) {
533  		regmap_update_bits(qspi->ctrl_base, qspi->ctrl_reg,
534  				   MEM_CS_MASK,
535  				   MEM_CS_EN(spi_get_chipselect(spi, 0)));
536  	}
537  	qspi->mmap_enabled = true;
538  	qspi->current_cs = spi_get_chipselect(spi, 0);
539  }
540  
ti_qspi_disable_memory_map(struct spi_device * spi)541  static void ti_qspi_disable_memory_map(struct spi_device *spi)
542  {
543  	struct ti_qspi  *qspi = spi_master_get_devdata(spi->master);
544  
545  	ti_qspi_write(qspi, 0, QSPI_SPI_SWITCH_REG);
546  	if (qspi->ctrl_base)
547  		regmap_update_bits(qspi->ctrl_base, qspi->ctrl_reg,
548  				   MEM_CS_MASK, 0);
549  	qspi->mmap_enabled = false;
550  	qspi->current_cs = -1;
551  }
552  
ti_qspi_setup_mmap_read(struct spi_device * spi,u8 opcode,u8 data_nbits,u8 addr_width,u8 dummy_bytes)553  static void ti_qspi_setup_mmap_read(struct spi_device *spi, u8 opcode,
554  				    u8 data_nbits, u8 addr_width,
555  				    u8 dummy_bytes)
556  {
557  	struct ti_qspi  *qspi = spi_master_get_devdata(spi->master);
558  	u32 memval = opcode;
559  
560  	switch (data_nbits) {
561  	case SPI_NBITS_QUAD:
562  		memval |= QSPI_SETUP_RD_QUAD;
563  		break;
564  	case SPI_NBITS_DUAL:
565  		memval |= QSPI_SETUP_RD_DUAL;
566  		break;
567  	default:
568  		memval |= QSPI_SETUP_RD_NORMAL;
569  		break;
570  	}
571  	memval |= ((addr_width - 1) << QSPI_SETUP_ADDR_SHIFT |
572  		   dummy_bytes << QSPI_SETUP_DUMMY_SHIFT);
573  	ti_qspi_write(qspi, memval,
574  		      QSPI_SPI_SETUP_REG(spi_get_chipselect(spi, 0)));
575  }
576  
ti_qspi_adjust_op_size(struct spi_mem * mem,struct spi_mem_op * op)577  static int ti_qspi_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op)
578  {
579  	struct ti_qspi *qspi = spi_controller_get_devdata(mem->spi->master);
580  	size_t max_len;
581  
582  	if (op->data.dir == SPI_MEM_DATA_IN) {
583  		if (op->addr.val < qspi->mmap_size) {
584  			/* Limit MMIO to the mmaped region */
585  			if (op->addr.val + op->data.nbytes > qspi->mmap_size) {
586  				max_len = qspi->mmap_size - op->addr.val;
587  				op->data.nbytes = min((size_t) op->data.nbytes,
588  						      max_len);
589  			}
590  		} else {
591  			/*
592  			 * Use fallback mode (SW generated transfers) above the
593  			 * mmaped region.
594  			 * Adjust size to comply with the QSPI max frame length.
595  			 */
596  			max_len = QSPI_FRAME;
597  			max_len -= 1 + op->addr.nbytes + op->dummy.nbytes;
598  			op->data.nbytes = min((size_t) op->data.nbytes,
599  					      max_len);
600  		}
601  	}
602  
603  	return 0;
604  }
605  
ti_qspi_exec_mem_op(struct spi_mem * mem,const struct spi_mem_op * op)606  static int ti_qspi_exec_mem_op(struct spi_mem *mem,
607  			       const struct spi_mem_op *op)
608  {
609  	struct ti_qspi *qspi = spi_master_get_devdata(mem->spi->master);
610  	u32 from = 0;
611  	int ret = 0;
612  
613  	/* Only optimize read path. */
614  	if (!op->data.nbytes || op->data.dir != SPI_MEM_DATA_IN ||
615  	    !op->addr.nbytes || op->addr.nbytes > 4)
616  		return -ENOTSUPP;
617  
618  	/* Address exceeds MMIO window size, fall back to regular mode. */
619  	from = op->addr.val;
620  	if (from + op->data.nbytes > qspi->mmap_size)
621  		return -ENOTSUPP;
622  
623  	mutex_lock(&qspi->list_lock);
624  
625  	if (!qspi->mmap_enabled || qspi->current_cs != spi_get_chipselect(mem->spi, 0)) {
626  		ti_qspi_setup_clk(qspi, mem->spi->max_speed_hz);
627  		ti_qspi_enable_memory_map(mem->spi);
628  	}
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_get_chipselect(spi, 0));
676  	if (spi->mode & SPI_CPOL)
677  		qspi->dc |= QSPI_CKPOL(spi_get_chipselect(spi, 0));
678  	if (spi->mode & SPI_CS_HIGH)
679  		qspi->dc |= QSPI_CSPOL(spi_get_chipselect(spi, 0));
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_get_chipselect(spi, 0));
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  		ti_qspi_setup_clk(qspi, t->speed_hz);
706  		ret = qspi_transfer_msg(qspi, t, transfer_len_words * wlen);
707  		if (ret) {
708  			dev_dbg(qspi->dev, "transfer message failed\n");
709  			mutex_unlock(&qspi->list_lock);
710  			return -EINVAL;
711  		}
712  
713  		m->actual_length += transfer_len_words * wlen;
714  		frame_len_words -= transfer_len_words;
715  		if (frame_len_words == 0)
716  			break;
717  	}
718  
719  	mutex_unlock(&qspi->list_lock);
720  
721  	ti_qspi_write(qspi, qspi->cmd | QSPI_INVAL, QSPI_SPI_CMD_REG);
722  	m->status = status;
723  	spi_finalize_current_message(master);
724  
725  	return status;
726  }
727  
ti_qspi_runtime_resume(struct device * dev)728  static int ti_qspi_runtime_resume(struct device *dev)
729  {
730  	struct ti_qspi      *qspi;
731  
732  	qspi = dev_get_drvdata(dev);
733  	ti_qspi_restore_ctx(qspi);
734  
735  	return 0;
736  }
737  
ti_qspi_dma_cleanup(struct ti_qspi * qspi)738  static void ti_qspi_dma_cleanup(struct ti_qspi *qspi)
739  {
740  	if (qspi->rx_bb_addr)
741  		dma_free_coherent(qspi->dev, QSPI_DMA_BUFFER_SIZE,
742  				  qspi->rx_bb_addr,
743  				  qspi->rx_bb_dma_addr);
744  
745  	if (qspi->rx_chan)
746  		dma_release_channel(qspi->rx_chan);
747  }
748  
749  static const struct of_device_id ti_qspi_match[] = {
750  	{.compatible = "ti,dra7xxx-qspi" },
751  	{.compatible = "ti,am4372-qspi" },
752  	{},
753  };
754  MODULE_DEVICE_TABLE(of, ti_qspi_match);
755  
ti_qspi_probe(struct platform_device * pdev)756  static int ti_qspi_probe(struct platform_device *pdev)
757  {
758  	struct  ti_qspi *qspi;
759  	struct spi_master *master;
760  	struct resource         *r, *res_mmap;
761  	struct device_node *np = pdev->dev.of_node;
762  	u32 max_freq;
763  	int ret = 0, num_cs, irq;
764  	dma_cap_mask_t mask;
765  
766  	master = spi_alloc_master(&pdev->dev, sizeof(*qspi));
767  	if (!master)
768  		return -ENOMEM;
769  
770  	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_RX_DUAL | SPI_RX_QUAD;
771  
772  	master->flags = SPI_CONTROLLER_HALF_DUPLEX;
773  	master->setup = ti_qspi_setup;
774  	master->auto_runtime_pm = true;
775  	master->transfer_one_message = ti_qspi_start_transfer_one;
776  	master->dev.of_node = pdev->dev.of_node;
777  	master->bits_per_word_mask = SPI_BPW_MASK(32) | SPI_BPW_MASK(16) |
778  				     SPI_BPW_MASK(8);
779  	master->mem_ops = &ti_qspi_mem_ops;
780  
781  	if (!of_property_read_u32(np, "num-cs", &num_cs))
782  		master->num_chipselect = num_cs;
783  
784  	qspi = spi_master_get_devdata(master);
785  	qspi->master = master;
786  	qspi->dev = &pdev->dev;
787  	platform_set_drvdata(pdev, qspi);
788  
789  	r = platform_get_resource_byname(pdev, IORESOURCE_MEM, "qspi_base");
790  	if (r == NULL) {
791  		r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
792  		if (r == NULL) {
793  			dev_err(&pdev->dev, "missing platform data\n");
794  			ret = -ENODEV;
795  			goto free_master;
796  		}
797  	}
798  
799  	res_mmap = platform_get_resource_byname(pdev,
800  			IORESOURCE_MEM, "qspi_mmap");
801  	if (res_mmap == NULL) {
802  		res_mmap = platform_get_resource(pdev, IORESOURCE_MEM, 1);
803  		if (res_mmap == NULL) {
804  			dev_err(&pdev->dev,
805  				"memory mapped resource not required\n");
806  		}
807  	}
808  
809  	if (res_mmap)
810  		qspi->mmap_size = resource_size(res_mmap);
811  
812  	irq = platform_get_irq(pdev, 0);
813  	if (irq < 0) {
814  		ret = irq;
815  		goto free_master;
816  	}
817  
818  	mutex_init(&qspi->list_lock);
819  
820  	qspi->base = devm_ioremap_resource(&pdev->dev, r);
821  	if (IS_ERR(qspi->base)) {
822  		ret = PTR_ERR(qspi->base);
823  		goto free_master;
824  	}
825  
826  
827  	if (of_property_read_bool(np, "syscon-chipselects")) {
828  		qspi->ctrl_base =
829  		syscon_regmap_lookup_by_phandle(np,
830  						"syscon-chipselects");
831  		if (IS_ERR(qspi->ctrl_base)) {
832  			ret = PTR_ERR(qspi->ctrl_base);
833  			goto free_master;
834  		}
835  		ret = of_property_read_u32_index(np,
836  						 "syscon-chipselects",
837  						 1, &qspi->ctrl_reg);
838  		if (ret) {
839  			dev_err(&pdev->dev,
840  				"couldn't get ctrl_mod reg index\n");
841  			goto free_master;
842  		}
843  	}
844  
845  	qspi->fclk = devm_clk_get(&pdev->dev, "fck");
846  	if (IS_ERR(qspi->fclk)) {
847  		ret = PTR_ERR(qspi->fclk);
848  		dev_err(&pdev->dev, "could not get clk: %d\n", ret);
849  	}
850  
851  	pm_runtime_use_autosuspend(&pdev->dev);
852  	pm_runtime_set_autosuspend_delay(&pdev->dev, QSPI_AUTOSUSPEND_TIMEOUT);
853  	pm_runtime_enable(&pdev->dev);
854  
855  	if (!of_property_read_u32(np, "spi-max-frequency", &max_freq))
856  		master->max_speed_hz = max_freq;
857  
858  	dma_cap_zero(mask);
859  	dma_cap_set(DMA_MEMCPY, mask);
860  
861  	qspi->rx_chan = dma_request_chan_by_mask(&mask);
862  	if (IS_ERR(qspi->rx_chan)) {
863  		dev_err(qspi->dev,
864  			"No Rx DMA available, trying mmap mode\n");
865  		qspi->rx_chan = NULL;
866  		ret = 0;
867  		goto no_dma;
868  	}
869  	qspi->rx_bb_addr = dma_alloc_coherent(qspi->dev,
870  					      QSPI_DMA_BUFFER_SIZE,
871  					      &qspi->rx_bb_dma_addr,
872  					      GFP_KERNEL | GFP_DMA);
873  	if (!qspi->rx_bb_addr) {
874  		dev_err(qspi->dev,
875  			"dma_alloc_coherent failed, using PIO mode\n");
876  		dma_release_channel(qspi->rx_chan);
877  		goto no_dma;
878  	}
879  	master->dma_rx = qspi->rx_chan;
880  	init_completion(&qspi->transfer_complete);
881  	if (res_mmap)
882  		qspi->mmap_phys_base = (dma_addr_t)res_mmap->start;
883  
884  no_dma:
885  	if (!qspi->rx_chan && res_mmap) {
886  		qspi->mmap_base = devm_ioremap_resource(&pdev->dev, res_mmap);
887  		if (IS_ERR(qspi->mmap_base)) {
888  			dev_info(&pdev->dev,
889  				 "mmap failed with error %ld using PIO mode\n",
890  				 PTR_ERR(qspi->mmap_base));
891  			qspi->mmap_base = NULL;
892  			master->mem_ops = NULL;
893  		}
894  	}
895  	qspi->mmap_enabled = false;
896  	qspi->current_cs = -1;
897  
898  	ret = devm_spi_register_master(&pdev->dev, master);
899  	if (!ret)
900  		return 0;
901  
902  	ti_qspi_dma_cleanup(qspi);
903  
904  	pm_runtime_disable(&pdev->dev);
905  free_master:
906  	spi_master_put(master);
907  	return ret;
908  }
909  
ti_qspi_remove(struct platform_device * pdev)910  static int ti_qspi_remove(struct platform_device *pdev)
911  {
912  	struct ti_qspi *qspi = platform_get_drvdata(pdev);
913  	int rc;
914  
915  	rc = spi_master_suspend(qspi->master);
916  	if (rc)
917  		return rc;
918  
919  	pm_runtime_put_sync(&pdev->dev);
920  	pm_runtime_disable(&pdev->dev);
921  
922  	ti_qspi_dma_cleanup(qspi);
923  
924  	return 0;
925  }
926  
927  static const struct dev_pm_ops ti_qspi_pm_ops = {
928  	.runtime_resume = ti_qspi_runtime_resume,
929  };
930  
931  static struct platform_driver ti_qspi_driver = {
932  	.probe	= ti_qspi_probe,
933  	.remove = ti_qspi_remove,
934  	.driver = {
935  		.name	= "ti-qspi",
936  		.pm =   &ti_qspi_pm_ops,
937  		.of_match_table = ti_qspi_match,
938  	}
939  };
940  
941  module_platform_driver(ti_qspi_driver);
942  
943  MODULE_AUTHOR("Sourav Poddar <sourav.poddar@ti.com>");
944  MODULE_LICENSE("GPL v2");
945  MODULE_DESCRIPTION("TI QSPI controller driver");
946  MODULE_ALIAS("platform:ti-qspi");
947