xref: /openbmc/linux/drivers/spi/spi-sn-f-ospi.c (revision 1edd0337)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Socionext SPI flash controller F_OSPI driver
4  * Copyright (C) 2021 Socionext Inc.
5  */
6 
7 #include <linux/bitfield.h>
8 #include <linux/clk.h>
9 #include <linux/io.h>
10 #include <linux/iopoll.h>
11 #include <linux/module.h>
12 #include <linux/mutex.h>
13 #include <linux/of_device.h>
14 #include <linux/platform_device.h>
15 #include <linux/spi/spi.h>
16 #include <linux/spi/spi-mem.h>
17 
18 /* Registers */
19 #define OSPI_PROT_CTL_INDIR			0x00
20 #define   OSPI_PROT_MODE_DATA_MASK		GENMASK(31, 30)
21 #define   OSPI_PROT_MODE_ALT_MASK		GENMASK(29, 28)
22 #define   OSPI_PROT_MODE_ADDR_MASK		GENMASK(27, 26)
23 #define   OSPI_PROT_MODE_CODE_MASK		GENMASK(25, 24)
24 #define     OSPI_PROT_MODE_SINGLE		0
25 #define     OSPI_PROT_MODE_DUAL			1
26 #define     OSPI_PROT_MODE_QUAD			2
27 #define     OSPI_PROT_MODE_OCTAL		3
28 #define   OSPI_PROT_DATA_RATE_DATA		BIT(23)
29 #define   OSPI_PROT_DATA_RATE_ALT		BIT(22)
30 #define   OSPI_PROT_DATA_RATE_ADDR		BIT(21)
31 #define   OSPI_PROT_DATA_RATE_CODE		BIT(20)
32 #define     OSPI_PROT_SDR			0
33 #define     OSPI_PROT_DDR			1
34 #define   OSPI_PROT_BIT_POS_DATA		BIT(19)
35 #define   OSPI_PROT_BIT_POS_ALT			BIT(18)
36 #define   OSPI_PROT_BIT_POS_ADDR		BIT(17)
37 #define   OSPI_PROT_BIT_POS_CODE		BIT(16)
38 #define   OSPI_PROT_SAMP_EDGE			BIT(12)
39 #define   OSPI_PROT_DATA_UNIT_MASK		GENMASK(11, 10)
40 #define     OSPI_PROT_DATA_UNIT_1B		0
41 #define     OSPI_PROT_DATA_UNIT_2B		1
42 #define     OSPI_PROT_DATA_UNIT_4B		3
43 #define   OSPI_PROT_TRANS_DIR_WRITE		BIT(9)
44 #define   OSPI_PROT_DATA_EN			BIT(8)
45 #define   OSPI_PROT_ALT_SIZE_MASK		GENMASK(7, 5)
46 #define   OSPI_PROT_ADDR_SIZE_MASK		GENMASK(4, 2)
47 #define   OSPI_PROT_CODE_SIZE_MASK		GENMASK(1, 0)
48 
49 #define OSPI_CLK_CTL				0x10
50 #define   OSPI_CLK_CTL_BOOT_INT_CLK_EN		BIT(16)
51 #define   OSPI_CLK_CTL_PHA			BIT(12)
52 #define     OSPI_CLK_CTL_PHA_180		0
53 #define     OSPI_CLK_CTL_PHA_90			1
54 #define   OSPI_CLK_CTL_DIV			GENMASK(9, 8)
55 #define     OSPI_CLK_CTL_DIV_1			0
56 #define     OSPI_CLK_CTL_DIV_2			1
57 #define     OSPI_CLK_CTL_DIV_4			2
58 #define     OSPI_CLK_CTL_DIV_8			3
59 #define   OSPI_CLK_CTL_INT_CLK_EN		BIT(0)
60 
61 #define OSPI_CS_CTL1				0x14
62 #define OSPI_CS_CTL2				0x18
63 #define OSPI_SSEL				0x20
64 #define OSPI_CMD_IDX_INDIR			0x40
65 #define OSPI_ADDR				0x50
66 #define OSPI_ALT_INDIR				0x60
67 #define OSPI_DMY_INDIR				0x70
68 #define OSPI_DAT				0x80
69 #define OSPI_DAT_SWP_INDIR			0x90
70 
71 #define OSPI_DAT_SIZE_INDIR			0xA0
72 #define   OSPI_DAT_SIZE_EN			BIT(15)
73 #define   OSPI_DAT_SIZE_MASK			GENMASK(10, 0)
74 #define   OSPI_DAT_SIZE_MAX			(OSPI_DAT_SIZE_MASK + 1)
75 
76 #define OSPI_TRANS_CTL				0xC0
77 #define   OSPI_TRANS_CTL_STOP_REQ		BIT(1)	/* RW1AC */
78 #define   OSPI_TRANS_CTL_START_REQ		BIT(0)	/* RW1AC */
79 
80 #define OSPI_ACC_MODE				0xC4
81 #define   OSPI_ACC_MODE_BOOT_DISABLE		BIT(0)
82 
83 #define OSPI_SWRST				0xD0
84 #define   OSPI_SWRST_INDIR_WRITE_FIFO		BIT(9)	/* RW1AC */
85 #define   OSPI_SWRST_INDIR_READ_FIFO		BIT(8)	/* RW1AC */
86 
87 #define OSPI_STAT				0xE0
88 #define   OSPI_STAT_IS_AXI_WRITING		BIT(10)
89 #define   OSPI_STAT_IS_AXI_READING		BIT(9)
90 #define   OSPI_STAT_IS_SPI_INT_CLK_STOP		BIT(4)
91 #define   OSPI_STAT_IS_SPI_IDLE			BIT(3)
92 
93 #define OSPI_IRQ				0xF0
94 #define   OSPI_IRQ_CS_DEASSERT			BIT(8)
95 #define   OSPI_IRQ_WRITE_BUF_READY		BIT(2)
96 #define   OSPI_IRQ_READ_BUF_READY		BIT(1)
97 #define   OSPI_IRQ_CS_TRANS_COMP		BIT(0)
98 #define   OSPI_IRQ_ALL				\
99 		(OSPI_IRQ_CS_DEASSERT | OSPI_IRQ_WRITE_BUF_READY \
100 		 | OSPI_IRQ_READ_BUF_READY | OSPI_IRQ_CS_TRANS_COMP)
101 
102 #define OSPI_IRQ_STAT_EN			0xF4
103 #define OSPI_IRQ_SIG_EN				0xF8
104 
105 /* Parameters */
106 #define OSPI_NUM_CS				4
107 #define OSPI_DUMMY_CYCLE_MAX			255
108 #define OSPI_WAIT_MAX_MSEC			100
109 
110 struct f_ospi {
111 	void __iomem *base;
112 	struct device *dev;
113 	struct clk *clk;
114 	struct mutex mlock;
115 };
116 
117 static u32 f_ospi_get_dummy_cycle(const struct spi_mem_op *op)
118 {
119 	return (op->dummy.nbytes * 8) / op->dummy.buswidth;
120 }
121 
122 static void f_ospi_clear_irq(struct f_ospi *ospi)
123 {
124 	writel(OSPI_IRQ_CS_DEASSERT | OSPI_IRQ_CS_TRANS_COMP,
125 	       ospi->base + OSPI_IRQ);
126 }
127 
128 static void f_ospi_enable_irq_status(struct f_ospi *ospi, u32 irq_bits)
129 {
130 	u32 val;
131 
132 	val = readl(ospi->base + OSPI_IRQ_STAT_EN);
133 	val |= irq_bits;
134 	writel(val, ospi->base + OSPI_IRQ_STAT_EN);
135 }
136 
137 static void f_ospi_disable_irq_status(struct f_ospi *ospi, u32 irq_bits)
138 {
139 	u32 val;
140 
141 	val = readl(ospi->base + OSPI_IRQ_STAT_EN);
142 	val &= ~irq_bits;
143 	writel(val, ospi->base + OSPI_IRQ_STAT_EN);
144 }
145 
146 static void f_ospi_disable_irq_output(struct f_ospi *ospi, u32 irq_bits)
147 {
148 	u32 val;
149 
150 	val = readl(ospi->base + OSPI_IRQ_SIG_EN);
151 	val &= ~irq_bits;
152 	writel(val, ospi->base + OSPI_IRQ_SIG_EN);
153 }
154 
155 static int f_ospi_prepare_config(struct f_ospi *ospi)
156 {
157 	u32 val, stat0, stat1;
158 
159 	/* G4: Disable internal clock */
160 	val = readl(ospi->base + OSPI_CLK_CTL);
161 	val &= ~(OSPI_CLK_CTL_BOOT_INT_CLK_EN | OSPI_CLK_CTL_INT_CLK_EN);
162 	writel(val, ospi->base + OSPI_CLK_CTL);
163 
164 	/* G5: Wait for stop */
165 	stat0 = OSPI_STAT_IS_AXI_WRITING | OSPI_STAT_IS_AXI_READING;
166 	stat1 = OSPI_STAT_IS_SPI_IDLE | OSPI_STAT_IS_SPI_INT_CLK_STOP;
167 
168 	return readl_poll_timeout(ospi->base + OSPI_STAT,
169 				  val, (val & (stat0 | stat1)) == stat1,
170 				  0, OSPI_WAIT_MAX_MSEC);
171 }
172 
173 static int f_ospi_unprepare_config(struct f_ospi *ospi)
174 {
175 	u32 val;
176 
177 	/* G11: Enable internal clock */
178 	val = readl(ospi->base + OSPI_CLK_CTL);
179 	val |= OSPI_CLK_CTL_BOOT_INT_CLK_EN | OSPI_CLK_CTL_INT_CLK_EN;
180 	writel(val, ospi->base + OSPI_CLK_CTL);
181 
182 	/* G12: Wait for clock to start */
183 	return readl_poll_timeout(ospi->base + OSPI_STAT,
184 				  val, !(val & OSPI_STAT_IS_SPI_INT_CLK_STOP),
185 				  0, OSPI_WAIT_MAX_MSEC);
186 }
187 
188 static void f_ospi_config_clk(struct f_ospi *ospi, u32 device_hz)
189 {
190 	long rate_hz = clk_get_rate(ospi->clk);
191 	u32 div = DIV_ROUND_UP(rate_hz, device_hz);
192 	u32 div_reg;
193 	u32 val;
194 
195 	if (rate_hz < device_hz) {
196 		dev_warn(ospi->dev, "Device frequency too large: %d\n",
197 			 device_hz);
198 		div_reg = OSPI_CLK_CTL_DIV_1;
199 	} else {
200 		if (div == 1) {
201 			div_reg = OSPI_CLK_CTL_DIV_1;
202 		} else if (div == 2) {
203 			div_reg = OSPI_CLK_CTL_DIV_2;
204 		} else if (div <= 4) {
205 			div_reg = OSPI_CLK_CTL_DIV_4;
206 		} else if (div <= 8) {
207 			div_reg = OSPI_CLK_CTL_DIV_8;
208 		} else {
209 			dev_warn(ospi->dev, "Device frequency too small: %d\n",
210 				 device_hz);
211 			div_reg = OSPI_CLK_CTL_DIV_8;
212 		}
213 	}
214 
215 	/*
216 	 * G7: Set clock mode
217 	 * clock phase is fixed at 180 degrees and configure edge direction
218 	 * instead.
219 	 */
220 	val = readl(ospi->base + OSPI_CLK_CTL);
221 
222 	val &= ~(OSPI_CLK_CTL_PHA | OSPI_CLK_CTL_DIV);
223 	val |= FIELD_PREP(OSPI_CLK_CTL_PHA, OSPI_CLK_CTL_PHA_180)
224 	     | FIELD_PREP(OSPI_CLK_CTL_DIV, div_reg);
225 
226 	writel(val, ospi->base + OSPI_CLK_CTL);
227 }
228 
229 static void f_ospi_config_dll(struct f_ospi *ospi)
230 {
231 	/* G8: Configure DLL, nothing */
232 }
233 
234 static u8 f_ospi_get_mode(struct f_ospi *ospi, int width, int data_size)
235 {
236 	u8 mode = OSPI_PROT_MODE_SINGLE;
237 
238 	switch (width) {
239 	case 1:
240 		mode = OSPI_PROT_MODE_SINGLE;
241 		break;
242 	case 2:
243 		mode = OSPI_PROT_MODE_DUAL;
244 		break;
245 	case 4:
246 		mode = OSPI_PROT_MODE_QUAD;
247 		break;
248 	case 8:
249 		mode = OSPI_PROT_MODE_OCTAL;
250 		break;
251 	default:
252 		if (data_size)
253 			dev_err(ospi->dev, "Invalid buswidth: %d\n", width);
254 		break;
255 	}
256 
257 	return mode;
258 }
259 
260 static void f_ospi_config_indir_protocol(struct f_ospi *ospi,
261 					 struct spi_mem *mem,
262 					 const struct spi_mem_op *op)
263 {
264 	struct spi_device *spi = mem->spi;
265 	u8 mode;
266 	u32 prot = 0, val;
267 	int unit;
268 
269 	/* Set one chip select */
270 	writel(BIT(spi->chip_select), ospi->base + OSPI_SSEL);
271 
272 	mode = f_ospi_get_mode(ospi, op->cmd.buswidth, 1);
273 	prot |= FIELD_PREP(OSPI_PROT_MODE_CODE_MASK, mode);
274 
275 	mode = f_ospi_get_mode(ospi, op->addr.buswidth, op->addr.nbytes);
276 	prot |= FIELD_PREP(OSPI_PROT_MODE_ADDR_MASK, mode);
277 
278 	mode = f_ospi_get_mode(ospi, op->data.buswidth, op->data.nbytes);
279 	prot |= FIELD_PREP(OSPI_PROT_MODE_DATA_MASK, mode);
280 
281 	prot |= FIELD_PREP(OSPI_PROT_DATA_RATE_DATA, OSPI_PROT_SDR);
282 	prot |= FIELD_PREP(OSPI_PROT_DATA_RATE_ALT,  OSPI_PROT_SDR);
283 	prot |= FIELD_PREP(OSPI_PROT_DATA_RATE_ADDR, OSPI_PROT_SDR);
284 	prot |= FIELD_PREP(OSPI_PROT_DATA_RATE_CODE, OSPI_PROT_SDR);
285 
286 	if (spi->mode & SPI_LSB_FIRST)
287 		prot |= OSPI_PROT_BIT_POS_DATA | OSPI_PROT_BIT_POS_ALT
288 		      | OSPI_PROT_BIT_POS_ADDR | OSPI_PROT_BIT_POS_CODE;
289 
290 	if (spi->mode & SPI_CPHA)
291 		prot |= OSPI_PROT_SAMP_EDGE;
292 
293 	/* Examine nbytes % 4 */
294 	switch (op->data.nbytes & 0x3) {
295 	case 0:
296 		unit = OSPI_PROT_DATA_UNIT_4B;
297 		val = 0;
298 		break;
299 	case 2:
300 		unit = OSPI_PROT_DATA_UNIT_2B;
301 		val = OSPI_DAT_SIZE_EN | (op->data.nbytes - 1);
302 		break;
303 	default:
304 		unit = OSPI_PROT_DATA_UNIT_1B;
305 		val = OSPI_DAT_SIZE_EN | (op->data.nbytes - 1);
306 		break;
307 	}
308 	prot |= FIELD_PREP(OSPI_PROT_DATA_UNIT_MASK, unit);
309 
310 	switch (op->data.dir) {
311 	case SPI_MEM_DATA_IN:
312 		prot |= OSPI_PROT_DATA_EN;
313 		break;
314 
315 	case SPI_MEM_DATA_OUT:
316 		prot |= OSPI_PROT_TRANS_DIR_WRITE | OSPI_PROT_DATA_EN;
317 		break;
318 
319 	case SPI_MEM_NO_DATA:
320 		prot |= OSPI_PROT_TRANS_DIR_WRITE;
321 		break;
322 
323 	default:
324 		dev_warn(ospi->dev, "Unsupported direction");
325 		break;
326 	}
327 
328 	prot |= FIELD_PREP(OSPI_PROT_ADDR_SIZE_MASK, op->addr.nbytes);
329 	prot |= FIELD_PREP(OSPI_PROT_CODE_SIZE_MASK, 1);	/* 1byte */
330 
331 	writel(prot, ospi->base + OSPI_PROT_CTL_INDIR);
332 	writel(val, ospi->base + OSPI_DAT_SIZE_INDIR);
333 }
334 
335 static int f_ospi_indir_prepare_op(struct f_ospi *ospi, struct spi_mem *mem,
336 				   const struct spi_mem_op *op)
337 {
338 	struct spi_device *spi = mem->spi;
339 	u32 irq_stat_en;
340 	int ret;
341 
342 	ret = f_ospi_prepare_config(ospi);
343 	if (ret)
344 		return ret;
345 
346 	f_ospi_config_clk(ospi, spi->max_speed_hz);
347 
348 	f_ospi_config_indir_protocol(ospi, mem, op);
349 
350 	writel(f_ospi_get_dummy_cycle(op), ospi->base + OSPI_DMY_INDIR);
351 	writel(op->addr.val, ospi->base + OSPI_ADDR);
352 	writel(op->cmd.opcode, ospi->base + OSPI_CMD_IDX_INDIR);
353 
354 	f_ospi_clear_irq(ospi);
355 
356 	switch (op->data.dir) {
357 	case SPI_MEM_DATA_IN:
358 		irq_stat_en = OSPI_IRQ_READ_BUF_READY | OSPI_IRQ_CS_TRANS_COMP;
359 		break;
360 
361 	case SPI_MEM_DATA_OUT:
362 		irq_stat_en = OSPI_IRQ_WRITE_BUF_READY | OSPI_IRQ_CS_TRANS_COMP;
363 		break;
364 
365 	case SPI_MEM_NO_DATA:
366 		irq_stat_en = OSPI_IRQ_CS_TRANS_COMP;
367 		break;
368 
369 	default:
370 		dev_warn(ospi->dev, "Unsupported direction");
371 		irq_stat_en = 0;
372 	}
373 
374 	f_ospi_disable_irq_status(ospi, ~irq_stat_en);
375 	f_ospi_enable_irq_status(ospi, irq_stat_en);
376 
377 	return f_ospi_unprepare_config(ospi);
378 }
379 
380 static void f_ospi_indir_start_xfer(struct f_ospi *ospi)
381 {
382 	/* Write only 1, auto cleared */
383 	writel(OSPI_TRANS_CTL_START_REQ, ospi->base + OSPI_TRANS_CTL);
384 }
385 
386 static void f_ospi_indir_stop_xfer(struct f_ospi *ospi)
387 {
388 	/* Write only 1, auto cleared */
389 	writel(OSPI_TRANS_CTL_STOP_REQ, ospi->base + OSPI_TRANS_CTL);
390 }
391 
392 static int f_ospi_indir_wait_xfer_complete(struct f_ospi *ospi)
393 {
394 	u32 val;
395 
396 	return readl_poll_timeout(ospi->base + OSPI_IRQ, val,
397 				  val & OSPI_IRQ_CS_TRANS_COMP,
398 				  0, OSPI_WAIT_MAX_MSEC);
399 }
400 
401 static int f_ospi_indir_read(struct f_ospi *ospi, struct spi_mem *mem,
402 			     const struct spi_mem_op *op)
403 {
404 	u8 *buf = op->data.buf.in;
405 	u32 val;
406 	int i, ret;
407 
408 	mutex_lock(&ospi->mlock);
409 
410 	/* E1-2: Prepare transfer operation */
411 	ret = f_ospi_indir_prepare_op(ospi, mem, op);
412 	if (ret)
413 		goto out;
414 
415 	f_ospi_indir_start_xfer(ospi);
416 
417 	/* E3-4: Wait for ready and read data */
418 	for (i = 0; i < op->data.nbytes; i++) {
419 		ret = readl_poll_timeout(ospi->base + OSPI_IRQ, val,
420 					 val & OSPI_IRQ_READ_BUF_READY,
421 					 0, OSPI_WAIT_MAX_MSEC);
422 		if (ret)
423 			goto out;
424 
425 		buf[i] = readl(ospi->base + OSPI_DAT) & 0xFF;
426 	}
427 
428 	/* E5-6: Stop transfer if data size is nothing */
429 	if (!(readl(ospi->base + OSPI_DAT_SIZE_INDIR) & OSPI_DAT_SIZE_EN))
430 		f_ospi_indir_stop_xfer(ospi);
431 
432 	/* E7-8: Wait for completion and clear */
433 	ret = f_ospi_indir_wait_xfer_complete(ospi);
434 	if (ret)
435 		goto out;
436 
437 	writel(OSPI_IRQ_CS_TRANS_COMP, ospi->base + OSPI_IRQ);
438 
439 	/* E9: Do nothing if data size is valid */
440 	if (readl(ospi->base + OSPI_DAT_SIZE_INDIR) & OSPI_DAT_SIZE_EN)
441 		goto out;
442 
443 	/* E10-11: Reset and check read fifo */
444 	writel(OSPI_SWRST_INDIR_READ_FIFO, ospi->base + OSPI_SWRST);
445 
446 	ret = readl_poll_timeout(ospi->base + OSPI_SWRST, val,
447 				 !(val & OSPI_SWRST_INDIR_READ_FIFO),
448 				 0, OSPI_WAIT_MAX_MSEC);
449 out:
450 	mutex_unlock(&ospi->mlock);
451 
452 	return ret;
453 }
454 
455 static int f_ospi_indir_write(struct f_ospi *ospi, struct spi_mem *mem,
456 			      const struct spi_mem_op *op)
457 {
458 	u8 *buf = (u8 *)op->data.buf.out;
459 	u32 val;
460 	int i, ret;
461 
462 	mutex_lock(&ospi->mlock);
463 
464 	/* F1-3: Prepare transfer operation */
465 	ret = f_ospi_indir_prepare_op(ospi, mem, op);
466 	if (ret)
467 		goto out;
468 
469 	f_ospi_indir_start_xfer(ospi);
470 
471 	if (!(readl(ospi->base + OSPI_PROT_CTL_INDIR) & OSPI_PROT_DATA_EN))
472 		goto nodata;
473 
474 	/* F4-5: Wait for buffer ready and write data */
475 	for (i = 0; i < op->data.nbytes; i++) {
476 		ret = readl_poll_timeout(ospi->base + OSPI_IRQ, val,
477 					 val & OSPI_IRQ_WRITE_BUF_READY,
478 					 0, OSPI_WAIT_MAX_MSEC);
479 		if (ret)
480 			goto out;
481 
482 		writel(buf[i], ospi->base + OSPI_DAT);
483 	}
484 
485 	/* F6-7: Stop transfer if data size is nothing */
486 	if (!(readl(ospi->base + OSPI_DAT_SIZE_INDIR) & OSPI_DAT_SIZE_EN))
487 		f_ospi_indir_stop_xfer(ospi);
488 
489 nodata:
490 	/* F8-9: Wait for completion and clear */
491 	ret = f_ospi_indir_wait_xfer_complete(ospi);
492 	if (ret)
493 		goto out;
494 
495 	writel(OSPI_IRQ_CS_TRANS_COMP, ospi->base + OSPI_IRQ);
496 out:
497 	mutex_unlock(&ospi->mlock);
498 
499 	return ret;
500 }
501 
502 static int f_ospi_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
503 {
504 	struct f_ospi *ospi = spi_controller_get_devdata(mem->spi->master);
505 	int err = 0;
506 
507 	switch (op->data.dir) {
508 	case SPI_MEM_DATA_IN:
509 		err = f_ospi_indir_read(ospi, mem, op);
510 		break;
511 
512 	case SPI_MEM_DATA_OUT:
513 		fallthrough;
514 	case SPI_MEM_NO_DATA:
515 		err = f_ospi_indir_write(ospi, mem, op);
516 		break;
517 
518 	default:
519 		dev_warn(ospi->dev, "Unsupported direction");
520 		err = -EOPNOTSUPP;
521 	}
522 
523 	return err;
524 }
525 
526 static bool f_ospi_supports_op_width(struct spi_mem *mem,
527 				     const struct spi_mem_op *op)
528 {
529 	u8 width_available[] = { 0, 1, 2, 4, 8 };
530 	u8 width_op[] = { op->cmd.buswidth, op->addr.buswidth,
531 			  op->dummy.buswidth, op->data.buswidth };
532 	bool is_match_found;
533 	int i, j;
534 
535 	for (i = 0; i < ARRAY_SIZE(width_op); i++) {
536 		is_match_found = false;
537 
538 		for (j = 0; j < ARRAY_SIZE(width_available); j++) {
539 			if (width_op[i] == width_available[j]) {
540 				is_match_found = true;
541 				break;
542 			}
543 		}
544 
545 		if (!is_match_found)
546 			return false;
547 	}
548 
549 	return true;
550 }
551 
552 static bool f_ospi_supports_op(struct spi_mem *mem,
553 			       const struct spi_mem_op *op)
554 {
555 	if (f_ospi_get_dummy_cycle(op) > OSPI_DUMMY_CYCLE_MAX)
556 		return false;
557 
558 	if (op->addr.nbytes > 4)
559 		return false;
560 
561 	if (!f_ospi_supports_op_width(mem, op))
562 		return false;
563 
564 	return true;
565 }
566 
567 static int f_ospi_adjust_op_size(struct spi_mem *mem, struct spi_mem_op *op)
568 {
569 	op->data.nbytes = min((int)op->data.nbytes, (int)(OSPI_DAT_SIZE_MAX));
570 
571 	return 0;
572 }
573 
574 static const struct spi_controller_mem_ops f_ospi_mem_ops = {
575 	.adjust_op_size = f_ospi_adjust_op_size,
576 	.supports_op = f_ospi_supports_op,
577 	.exec_op = f_ospi_exec_op,
578 };
579 
580 static int f_ospi_init(struct f_ospi *ospi)
581 {
582 	int ret;
583 
584 	ret = f_ospi_prepare_config(ospi);
585 	if (ret)
586 		return ret;
587 
588 	/* Disable boot signal */
589 	writel(OSPI_ACC_MODE_BOOT_DISABLE, ospi->base + OSPI_ACC_MODE);
590 
591 	f_ospi_config_dll(ospi);
592 
593 	/* Disable IRQ */
594 	f_ospi_clear_irq(ospi);
595 	f_ospi_disable_irq_status(ospi, OSPI_IRQ_ALL);
596 	f_ospi_disable_irq_output(ospi, OSPI_IRQ_ALL);
597 
598 	return f_ospi_unprepare_config(ospi);
599 }
600 
601 static int f_ospi_probe(struct platform_device *pdev)
602 {
603 	struct spi_controller *ctlr;
604 	struct device *dev = &pdev->dev;
605 	struct f_ospi *ospi;
606 	u32 num_cs = OSPI_NUM_CS;
607 	int ret;
608 
609 	ctlr = spi_alloc_master(dev, sizeof(*ospi));
610 	if (!ctlr)
611 		return -ENOMEM;
612 
613 	ctlr->mode_bits = SPI_TX_DUAL | SPI_TX_QUAD | SPI_TX_OCTAL
614 		| SPI_RX_DUAL | SPI_RX_QUAD | SPI_RX_OCTAL
615 		| SPI_MODE_0 | SPI_MODE_1 | SPI_LSB_FIRST;
616 	ctlr->mem_ops = &f_ospi_mem_ops;
617 	ctlr->bus_num = -1;
618 	of_property_read_u32(dev->of_node, "num-cs", &num_cs);
619 	if (num_cs > OSPI_NUM_CS) {
620 		dev_err(dev, "num-cs too large: %d\n", num_cs);
621 		return -ENOMEM;
622 	}
623 	ctlr->num_chipselect = num_cs;
624 	ctlr->dev.of_node = dev->of_node;
625 
626 	ospi = spi_controller_get_devdata(ctlr);
627 	ospi->dev = dev;
628 
629 	platform_set_drvdata(pdev, ospi);
630 
631 	ospi->base = devm_platform_ioremap_resource(pdev, 0);
632 	if (IS_ERR(ospi->base)) {
633 		ret = PTR_ERR(ospi->base);
634 		goto err_put_ctlr;
635 	}
636 
637 	ospi->clk = devm_clk_get(dev, NULL);
638 	if (IS_ERR(ospi->clk)) {
639 		ret = PTR_ERR(ospi->clk);
640 		goto err_put_ctlr;
641 	}
642 
643 	ret = clk_prepare_enable(ospi->clk);
644 	if (ret) {
645 		dev_err(dev, "Failed to enable the clock\n");
646 		goto err_disable_clk;
647 	}
648 
649 	mutex_init(&ospi->mlock);
650 
651 	ret = f_ospi_init(ospi);
652 	if (ret)
653 		goto err_destroy_mutex;
654 
655 	ret = devm_spi_register_controller(dev, ctlr);
656 	if (ret)
657 		goto err_destroy_mutex;
658 
659 	return 0;
660 
661 err_destroy_mutex:
662 	mutex_destroy(&ospi->mlock);
663 
664 err_disable_clk:
665 	clk_disable_unprepare(ospi->clk);
666 
667 err_put_ctlr:
668 	spi_controller_put(ctlr);
669 
670 	return ret;
671 }
672 
673 static int f_ospi_remove(struct platform_device *pdev)
674 {
675 	struct f_ospi *ospi = platform_get_drvdata(pdev);
676 
677 	clk_disable_unprepare(ospi->clk);
678 
679 	mutex_destroy(&ospi->mlock);
680 
681 	return 0;
682 }
683 
684 static const struct of_device_id f_ospi_dt_ids[] = {
685 	{ .compatible = "socionext,f-ospi" },
686 	{}
687 };
688 MODULE_DEVICE_TABLE(of, f_ospi_dt_ids);
689 
690 static struct platform_driver f_ospi_driver = {
691 	.driver = {
692 		.name = "socionext,f-ospi",
693 		.of_match_table = f_ospi_dt_ids,
694 	},
695 	.probe = f_ospi_probe,
696 	.remove = f_ospi_remove,
697 };
698 module_platform_driver(f_ospi_driver);
699 
700 MODULE_DESCRIPTION("Socionext F_OSPI controller driver");
701 MODULE_AUTHOR("Socionext Inc.");
702 MODULE_AUTHOR("Kunihiko Hayashi <hayashi.kunihiko@socionext.com>");
703 MODULE_LICENSE("GPL");
704