xref: /openbmc/linux/drivers/spi/atmel-quadspi.c (revision 360823a09426347ea8f232b0b0b5156d0aed0302)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Driver for Atmel QSPI Controller
4  *
5  * Copyright (C) 2015 Atmel Corporation
6  * Copyright (C) 2018 Cryptera A/S
7  *
8  * Author: Cyrille Pitchen <cyrille.pitchen@atmel.com>
9  * Author: Piotr Bugalski <bugalski.piotr@gmail.com>
10  *
11  * This driver is based on drivers/mtd/spi-nor/fsl-quadspi.c from Freescale.
12  */
13 
14 #include <linux/clk.h>
15 #include <linux/delay.h>
16 #include <linux/err.h>
17 #include <linux/interrupt.h>
18 #include <linux/io.h>
19 #include <linux/kernel.h>
20 #include <linux/module.h>
21 #include <linux/of.h>
22 #include <linux/of_platform.h>
23 #include <linux/platform_device.h>
24 #include <linux/pm_runtime.h>
25 #include <linux/spi/spi-mem.h>
26 
27 /* QSPI register offsets */
28 #define QSPI_CR      0x0000  /* Control Register */
29 #define QSPI_MR      0x0004  /* Mode Register */
30 #define QSPI_RD      0x0008  /* Receive Data Register */
31 #define QSPI_TD      0x000c  /* Transmit Data Register */
32 #define QSPI_SR      0x0010  /* Status Register */
33 #define QSPI_IER     0x0014  /* Interrupt Enable Register */
34 #define QSPI_IDR     0x0018  /* Interrupt Disable Register */
35 #define QSPI_IMR     0x001c  /* Interrupt Mask Register */
36 #define QSPI_SCR     0x0020  /* Serial Clock Register */
37 
38 #define QSPI_IAR     0x0030  /* Instruction Address Register */
39 #define QSPI_ICR     0x0034  /* Instruction Code Register */
40 #define QSPI_WICR    0x0034  /* Write Instruction Code Register */
41 #define QSPI_IFR     0x0038  /* Instruction Frame Register */
42 #define QSPI_RICR    0x003C  /* Read Instruction Code Register */
43 
44 #define QSPI_SMR     0x0040  /* Scrambling Mode Register */
45 #define QSPI_SKR     0x0044  /* Scrambling Key Register */
46 
47 #define QSPI_WPMR    0x00E4  /* Write Protection Mode Register */
48 #define QSPI_WPSR    0x00E8  /* Write Protection Status Register */
49 
50 #define QSPI_VERSION 0x00FC  /* Version Register */
51 
52 
53 /* Bitfields in QSPI_CR (Control Register) */
54 #define QSPI_CR_QSPIEN                  BIT(0)
55 #define QSPI_CR_QSPIDIS                 BIT(1)
56 #define QSPI_CR_SWRST                   BIT(7)
57 #define QSPI_CR_LASTXFER                BIT(24)
58 
59 /* Bitfields in QSPI_MR (Mode Register) */
60 #define QSPI_MR_SMM                     BIT(0)
61 #define QSPI_MR_LLB                     BIT(1)
62 #define QSPI_MR_WDRBT                   BIT(2)
63 #define QSPI_MR_SMRM                    BIT(3)
64 #define QSPI_MR_CSMODE_MASK             GENMASK(5, 4)
65 #define QSPI_MR_CSMODE_NOT_RELOADED     (0 << 4)
66 #define QSPI_MR_CSMODE_LASTXFER         (1 << 4)
67 #define QSPI_MR_CSMODE_SYSTEMATICALLY   (2 << 4)
68 #define QSPI_MR_NBBITS_MASK             GENMASK(11, 8)
69 #define QSPI_MR_NBBITS(n)               ((((n) - 8) << 8) & QSPI_MR_NBBITS_MASK)
70 #define QSPI_MR_DLYBCT_MASK             GENMASK(23, 16)
71 #define QSPI_MR_DLYBCT(n)               (((n) << 16) & QSPI_MR_DLYBCT_MASK)
72 #define QSPI_MR_DLYCS_MASK              GENMASK(31, 24)
73 #define QSPI_MR_DLYCS(n)                (((n) << 24) & QSPI_MR_DLYCS_MASK)
74 
75 /* Bitfields in QSPI_SR/QSPI_IER/QSPI_IDR/QSPI_IMR  */
76 #define QSPI_SR_RDRF                    BIT(0)
77 #define QSPI_SR_TDRE                    BIT(1)
78 #define QSPI_SR_TXEMPTY                 BIT(2)
79 #define QSPI_SR_OVRES                   BIT(3)
80 #define QSPI_SR_CSR                     BIT(8)
81 #define QSPI_SR_CSS                     BIT(9)
82 #define QSPI_SR_INSTRE                  BIT(10)
83 #define QSPI_SR_QSPIENS                 BIT(24)
84 
85 #define QSPI_SR_CMD_COMPLETED	(QSPI_SR_INSTRE | QSPI_SR_CSR)
86 
87 /* Bitfields in QSPI_SCR (Serial Clock Register) */
88 #define QSPI_SCR_CPOL                   BIT(0)
89 #define QSPI_SCR_CPHA                   BIT(1)
90 #define QSPI_SCR_SCBR_MASK              GENMASK(15, 8)
91 #define QSPI_SCR_SCBR(n)                (((n) << 8) & QSPI_SCR_SCBR_MASK)
92 #define QSPI_SCR_DLYBS_MASK             GENMASK(23, 16)
93 #define QSPI_SCR_DLYBS(n)               (((n) << 16) & QSPI_SCR_DLYBS_MASK)
94 
95 /* Bitfields in QSPI_ICR (Read/Write Instruction Code Register) */
96 #define QSPI_ICR_INST_MASK              GENMASK(7, 0)
97 #define QSPI_ICR_INST(inst)             (((inst) << 0) & QSPI_ICR_INST_MASK)
98 #define QSPI_ICR_OPT_MASK               GENMASK(23, 16)
99 #define QSPI_ICR_OPT(opt)               (((opt) << 16) & QSPI_ICR_OPT_MASK)
100 
101 /* Bitfields in QSPI_IFR (Instruction Frame Register) */
102 #define QSPI_IFR_WIDTH_MASK             GENMASK(2, 0)
103 #define QSPI_IFR_WIDTH_SINGLE_BIT_SPI   (0 << 0)
104 #define QSPI_IFR_WIDTH_DUAL_OUTPUT      (1 << 0)
105 #define QSPI_IFR_WIDTH_QUAD_OUTPUT      (2 << 0)
106 #define QSPI_IFR_WIDTH_DUAL_IO          (3 << 0)
107 #define QSPI_IFR_WIDTH_QUAD_IO          (4 << 0)
108 #define QSPI_IFR_WIDTH_DUAL_CMD         (5 << 0)
109 #define QSPI_IFR_WIDTH_QUAD_CMD         (6 << 0)
110 #define QSPI_IFR_INSTEN                 BIT(4)
111 #define QSPI_IFR_ADDREN                 BIT(5)
112 #define QSPI_IFR_OPTEN                  BIT(6)
113 #define QSPI_IFR_DATAEN                 BIT(7)
114 #define QSPI_IFR_OPTL_MASK              GENMASK(9, 8)
115 #define QSPI_IFR_OPTL_1BIT              (0 << 8)
116 #define QSPI_IFR_OPTL_2BIT              (1 << 8)
117 #define QSPI_IFR_OPTL_4BIT              (2 << 8)
118 #define QSPI_IFR_OPTL_8BIT              (3 << 8)
119 #define QSPI_IFR_ADDRL                  BIT(10)
120 #define QSPI_IFR_TFRTYP_MEM		BIT(12)
121 #define QSPI_IFR_SAMA5D2_WRITE_TRSFR	BIT(13)
122 #define QSPI_IFR_CRM                    BIT(14)
123 #define QSPI_IFR_NBDUM_MASK             GENMASK(20, 16)
124 #define QSPI_IFR_NBDUM(n)               (((n) << 16) & QSPI_IFR_NBDUM_MASK)
125 #define QSPI_IFR_APBTFRTYP_READ		BIT(24)	/* Defined in SAM9X60 */
126 
127 /* Bitfields in QSPI_SMR (Scrambling Mode Register) */
128 #define QSPI_SMR_SCREN                  BIT(0)
129 #define QSPI_SMR_RVDIS                  BIT(1)
130 
131 /* Bitfields in QSPI_WPMR (Write Protection Mode Register) */
132 #define QSPI_WPMR_WPEN                  BIT(0)
133 #define QSPI_WPMR_WPKEY_MASK            GENMASK(31, 8)
134 #define QSPI_WPMR_WPKEY(wpkey)          (((wpkey) << 8) & QSPI_WPMR_WPKEY_MASK)
135 
136 /* Bitfields in QSPI_WPSR (Write Protection Status Register) */
137 #define QSPI_WPSR_WPVS                  BIT(0)
138 #define QSPI_WPSR_WPVSRC_MASK           GENMASK(15, 8)
139 #define QSPI_WPSR_WPVSRC(src)           (((src) << 8) & QSPI_WPSR_WPVSRC)
140 
141 #define ATMEL_QSPI_TIMEOUT		1000	/* ms */
142 
143 struct atmel_qspi_caps {
144 	bool has_qspick;
145 	bool has_ricr;
146 };
147 
148 struct atmel_qspi_ops;
149 
150 struct atmel_qspi {
151 	void __iomem		*regs;
152 	void __iomem		*mem;
153 	struct clk		*pclk;
154 	struct clk		*qspick;
155 	struct platform_device	*pdev;
156 	const struct atmel_qspi_caps *caps;
157 	const struct atmel_qspi_ops *ops;
158 	resource_size_t		mmap_size;
159 	u32			pending;
160 	u32			irq_mask;
161 	u32			mr;
162 	u32			scr;
163 	struct completion	cmd_completion;
164 };
165 
166 struct atmel_qspi_ops {
167 	int (*set_cfg)(struct atmel_qspi *aq, const struct spi_mem_op *op,
168 		       u32 *offset);
169 	int (*transfer)(struct spi_mem *mem, const struct spi_mem_op *op,
170 			u32 offset);
171 };
172 
173 struct atmel_qspi_mode {
174 	u8 cmd_buswidth;
175 	u8 addr_buswidth;
176 	u8 data_buswidth;
177 	u32 config;
178 };
179 
180 static const struct atmel_qspi_mode atmel_qspi_modes[] = {
181 	{ 1, 1, 1, QSPI_IFR_WIDTH_SINGLE_BIT_SPI },
182 	{ 1, 1, 2, QSPI_IFR_WIDTH_DUAL_OUTPUT },
183 	{ 1, 1, 4, QSPI_IFR_WIDTH_QUAD_OUTPUT },
184 	{ 1, 2, 2, QSPI_IFR_WIDTH_DUAL_IO },
185 	{ 1, 4, 4, QSPI_IFR_WIDTH_QUAD_IO },
186 	{ 2, 2, 2, QSPI_IFR_WIDTH_DUAL_CMD },
187 	{ 4, 4, 4, QSPI_IFR_WIDTH_QUAD_CMD },
188 };
189 
190 #ifdef VERBOSE_DEBUG
atmel_qspi_reg_name(u32 offset,char * tmp,size_t sz)191 static const char *atmel_qspi_reg_name(u32 offset, char *tmp, size_t sz)
192 {
193 	switch (offset) {
194 	case QSPI_CR:
195 		return "CR";
196 	case QSPI_MR:
197 		return "MR";
198 	case QSPI_RD:
199 		return "RD";
200 	case QSPI_TD:
201 		return "TD";
202 	case QSPI_SR:
203 		return "SR";
204 	case QSPI_IER:
205 		return "IER";
206 	case QSPI_IDR:
207 		return "IDR";
208 	case QSPI_IMR:
209 		return "IMR";
210 	case QSPI_SCR:
211 		return "SCR";
212 	case QSPI_IAR:
213 		return "IAR";
214 	case QSPI_ICR:
215 		return "ICR/WICR";
216 	case QSPI_IFR:
217 		return "IFR";
218 	case QSPI_RICR:
219 		return "RICR";
220 	case QSPI_SMR:
221 		return "SMR";
222 	case QSPI_SKR:
223 		return "SKR";
224 	case QSPI_WPMR:
225 		return "WPMR";
226 	case QSPI_WPSR:
227 		return "WPSR";
228 	case QSPI_VERSION:
229 		return "VERSION";
230 	default:
231 		snprintf(tmp, sz, "0x%02x", offset);
232 		break;
233 	}
234 
235 	return tmp;
236 }
237 #endif /* VERBOSE_DEBUG */
238 
atmel_qspi_read(struct atmel_qspi * aq,u32 offset)239 static u32 atmel_qspi_read(struct atmel_qspi *aq, u32 offset)
240 {
241 	u32 value = readl_relaxed(aq->regs + offset);
242 
243 #ifdef VERBOSE_DEBUG
244 	char tmp[8];
245 
246 	dev_vdbg(&aq->pdev->dev, "read 0x%08x from %s\n", value,
247 		 atmel_qspi_reg_name(offset, tmp, sizeof(tmp)));
248 #endif /* VERBOSE_DEBUG */
249 
250 	return value;
251 }
252 
atmel_qspi_write(u32 value,struct atmel_qspi * aq,u32 offset)253 static void atmel_qspi_write(u32 value, struct atmel_qspi *aq, u32 offset)
254 {
255 #ifdef VERBOSE_DEBUG
256 	char tmp[8];
257 
258 	dev_vdbg(&aq->pdev->dev, "write 0x%08x into %s\n", value,
259 		 atmel_qspi_reg_name(offset, tmp, sizeof(tmp)));
260 #endif /* VERBOSE_DEBUG */
261 
262 	writel_relaxed(value, aq->regs + offset);
263 }
264 
atmel_qspi_is_compatible(const struct spi_mem_op * op,const struct atmel_qspi_mode * mode)265 static inline bool atmel_qspi_is_compatible(const struct spi_mem_op *op,
266 					    const struct atmel_qspi_mode *mode)
267 {
268 	if (op->cmd.buswidth != mode->cmd_buswidth)
269 		return false;
270 
271 	if (op->addr.nbytes && op->addr.buswidth != mode->addr_buswidth)
272 		return false;
273 
274 	if (op->data.nbytes && op->data.buswidth != mode->data_buswidth)
275 		return false;
276 
277 	return true;
278 }
279 
atmel_qspi_find_mode(const struct spi_mem_op * op)280 static int atmel_qspi_find_mode(const struct spi_mem_op *op)
281 {
282 	u32 i;
283 
284 	for (i = 0; i < ARRAY_SIZE(atmel_qspi_modes); i++)
285 		if (atmel_qspi_is_compatible(op, &atmel_qspi_modes[i]))
286 			return i;
287 
288 	return -ENOTSUPP;
289 }
290 
atmel_qspi_supports_op(struct spi_mem * mem,const struct spi_mem_op * op)291 static bool atmel_qspi_supports_op(struct spi_mem *mem,
292 				   const struct spi_mem_op *op)
293 {
294 	if (!spi_mem_default_supports_op(mem, op))
295 		return false;
296 
297 	if (atmel_qspi_find_mode(op) < 0)
298 		return false;
299 
300 	/* special case not supported by hardware */
301 	if (op->addr.nbytes == 2 && op->cmd.buswidth != op->addr.buswidth &&
302 	    op->dummy.nbytes == 0)
303 		return false;
304 
305 	return true;
306 }
307 
atmel_qspi_set_cfg(struct atmel_qspi * aq,const struct spi_mem_op * op,u32 * offset)308 static int atmel_qspi_set_cfg(struct atmel_qspi *aq,
309 			      const struct spi_mem_op *op, u32 *offset)
310 {
311 	u32 iar, icr, ifr;
312 	u32 dummy_cycles = 0;
313 	int mode;
314 
315 	iar = 0;
316 	icr = QSPI_ICR_INST(op->cmd.opcode);
317 	ifr = QSPI_IFR_INSTEN;
318 
319 	mode = atmel_qspi_find_mode(op);
320 	if (mode < 0)
321 		return mode;
322 	ifr |= atmel_qspi_modes[mode].config;
323 
324 	if (op->dummy.nbytes)
325 		dummy_cycles = op->dummy.nbytes * 8 / op->dummy.buswidth;
326 
327 	/*
328 	 * The controller allows 24 and 32-bit addressing while NAND-flash
329 	 * requires 16-bit long. Handling 8-bit long addresses is done using
330 	 * the option field. For the 16-bit addresses, the workaround depends
331 	 * of the number of requested dummy bits. If there are 8 or more dummy
332 	 * cycles, the address is shifted and sent with the first dummy byte.
333 	 * Otherwise opcode is disabled and the first byte of the address
334 	 * contains the command opcode (works only if the opcode and address
335 	 * use the same buswidth). The limitation is when the 16-bit address is
336 	 * used without enough dummy cycles and the opcode is using a different
337 	 * buswidth than the address.
338 	 */
339 	if (op->addr.buswidth) {
340 		switch (op->addr.nbytes) {
341 		case 0:
342 			break;
343 		case 1:
344 			ifr |= QSPI_IFR_OPTEN | QSPI_IFR_OPTL_8BIT;
345 			icr |= QSPI_ICR_OPT(op->addr.val & 0xff);
346 			break;
347 		case 2:
348 			if (dummy_cycles < 8 / op->addr.buswidth) {
349 				ifr &= ~QSPI_IFR_INSTEN;
350 				ifr |= QSPI_IFR_ADDREN;
351 				iar = (op->cmd.opcode << 16) |
352 					(op->addr.val & 0xffff);
353 			} else {
354 				ifr |= QSPI_IFR_ADDREN;
355 				iar = (op->addr.val << 8) & 0xffffff;
356 				dummy_cycles -= 8 / op->addr.buswidth;
357 			}
358 			break;
359 		case 3:
360 			ifr |= QSPI_IFR_ADDREN;
361 			iar = op->addr.val & 0xffffff;
362 			break;
363 		case 4:
364 			ifr |= QSPI_IFR_ADDREN | QSPI_IFR_ADDRL;
365 			iar = op->addr.val & 0x7ffffff;
366 			break;
367 		default:
368 			return -ENOTSUPP;
369 		}
370 	}
371 
372 	/* offset of the data access in the QSPI memory space */
373 	*offset = iar;
374 
375 	/* Set number of dummy cycles */
376 	if (dummy_cycles)
377 		ifr |= QSPI_IFR_NBDUM(dummy_cycles);
378 
379 	/* Set data enable and data transfer type. */
380 	if (op->data.nbytes) {
381 		ifr |= QSPI_IFR_DATAEN;
382 
383 		if (op->addr.nbytes)
384 			ifr |= QSPI_IFR_TFRTYP_MEM;
385 	}
386 
387 	/*
388 	 * If the QSPI controller is set in regular SPI mode, set it in
389 	 * Serial Memory Mode (SMM).
390 	 */
391 	if (!(aq->mr & QSPI_MR_SMM)) {
392 		aq->mr |= QSPI_MR_SMM;
393 		atmel_qspi_write(aq->mr, aq, QSPI_MR);
394 	}
395 
396 	/* Clear pending interrupts */
397 	(void)atmel_qspi_read(aq, QSPI_SR);
398 
399 	/* Set QSPI Instruction Frame registers. */
400 	if (op->addr.nbytes && !op->data.nbytes)
401 		atmel_qspi_write(iar, aq, QSPI_IAR);
402 
403 	if (aq->caps->has_ricr) {
404 		if (op->data.dir == SPI_MEM_DATA_IN)
405 			atmel_qspi_write(icr, aq, QSPI_RICR);
406 		else
407 			atmel_qspi_write(icr, aq, QSPI_WICR);
408 	} else {
409 		if (op->data.nbytes && op->data.dir == SPI_MEM_DATA_OUT)
410 			ifr |= QSPI_IFR_SAMA5D2_WRITE_TRSFR;
411 
412 		atmel_qspi_write(icr, aq, QSPI_ICR);
413 	}
414 
415 	atmel_qspi_write(ifr, aq, QSPI_IFR);
416 
417 	return 0;
418 }
419 
atmel_qspi_wait_for_completion(struct atmel_qspi * aq,u32 irq_mask)420 static int atmel_qspi_wait_for_completion(struct atmel_qspi *aq, u32 irq_mask)
421 {
422 	int err = 0;
423 	u32 sr;
424 
425 	/* Poll INSTRuction End status */
426 	sr = atmel_qspi_read(aq, QSPI_SR);
427 	if ((sr & irq_mask) == irq_mask)
428 		return 0;
429 
430 	/* Wait for INSTRuction End interrupt */
431 	reinit_completion(&aq->cmd_completion);
432 	aq->pending = sr & irq_mask;
433 	aq->irq_mask = irq_mask;
434 	atmel_qspi_write(irq_mask, aq, QSPI_IER);
435 	if (!wait_for_completion_timeout(&aq->cmd_completion,
436 					 msecs_to_jiffies(ATMEL_QSPI_TIMEOUT)))
437 		err = -ETIMEDOUT;
438 	atmel_qspi_write(irq_mask, aq, QSPI_IDR);
439 
440 	return err;
441 }
442 
atmel_qspi_transfer(struct spi_mem * mem,const struct spi_mem_op * op,u32 offset)443 static int atmel_qspi_transfer(struct spi_mem *mem,
444 			       const struct spi_mem_op *op, u32 offset)
445 {
446 	struct atmel_qspi *aq = spi_controller_get_devdata(mem->spi->controller);
447 
448 	/* Skip to the final steps if there is no data */
449 	if (!op->data.nbytes)
450 		return atmel_qspi_wait_for_completion(aq,
451 						      QSPI_SR_CMD_COMPLETED);
452 
453 	/* Dummy read of QSPI_IFR to synchronize APB and AHB accesses */
454 	(void)atmel_qspi_read(aq, QSPI_IFR);
455 
456 	/* Send/Receive data */
457 	if (op->data.dir == SPI_MEM_DATA_IN) {
458 		memcpy_fromio(op->data.buf.in, aq->mem + offset,
459 			      op->data.nbytes);
460 
461 		/* Synchronize AHB and APB accesses again */
462 		rmb();
463 	} else {
464 		memcpy_toio(aq->mem + offset, op->data.buf.out,
465 			    op->data.nbytes);
466 
467 		/* Synchronize AHB and APB accesses again */
468 		wmb();
469 	}
470 
471 	/* Release the chip-select */
472 	atmel_qspi_write(QSPI_CR_LASTXFER, aq, QSPI_CR);
473 
474 	return atmel_qspi_wait_for_completion(aq, QSPI_SR_CMD_COMPLETED);
475 }
476 
atmel_qspi_exec_op(struct spi_mem * mem,const struct spi_mem_op * op)477 static int atmel_qspi_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
478 {
479 	struct atmel_qspi *aq = spi_controller_get_devdata(mem->spi->controller);
480 	u32 offset;
481 	int err;
482 
483 	/*
484 	 * Check if the address exceeds the MMIO window size. An improvement
485 	 * would be to add support for regular SPI mode and fall back to it
486 	 * when the flash memories overrun the controller's memory space.
487 	 */
488 	if (op->addr.val + op->data.nbytes > aq->mmap_size)
489 		return -EOPNOTSUPP;
490 
491 	if (op->addr.nbytes > 4)
492 		return -EOPNOTSUPP;
493 
494 	err = pm_runtime_resume_and_get(&aq->pdev->dev);
495 	if (err < 0)
496 		return err;
497 
498 	err = aq->ops->set_cfg(aq, op, &offset);
499 	if (err)
500 		goto pm_runtime_put;
501 
502 	err = aq->ops->transfer(mem, op, offset);
503 
504 pm_runtime_put:
505 	pm_runtime_mark_last_busy(&aq->pdev->dev);
506 	pm_runtime_put_autosuspend(&aq->pdev->dev);
507 	return err;
508 }
509 
atmel_qspi_get_name(struct spi_mem * spimem)510 static const char *atmel_qspi_get_name(struct spi_mem *spimem)
511 {
512 	return dev_name(spimem->spi->dev.parent);
513 }
514 
515 static const struct spi_controller_mem_ops atmel_qspi_mem_ops = {
516 	.supports_op = atmel_qspi_supports_op,
517 	.exec_op = atmel_qspi_exec_op,
518 	.get_name = atmel_qspi_get_name
519 };
520 
atmel_qspi_setup(struct spi_device * spi)521 static int atmel_qspi_setup(struct spi_device *spi)
522 {
523 	struct spi_controller *ctrl = spi->controller;
524 	struct atmel_qspi *aq = spi_controller_get_devdata(ctrl);
525 	unsigned long src_rate;
526 	u32 scbr;
527 	int ret;
528 
529 	if (ctrl->busy)
530 		return -EBUSY;
531 
532 	if (!spi->max_speed_hz)
533 		return -EINVAL;
534 
535 	src_rate = clk_get_rate(aq->pclk);
536 	if (!src_rate)
537 		return -EINVAL;
538 
539 	/* Compute the QSPI baudrate */
540 	scbr = DIV_ROUND_UP(src_rate, spi->max_speed_hz);
541 	if (scbr > 0)
542 		scbr--;
543 
544 	ret = pm_runtime_resume_and_get(ctrl->dev.parent);
545 	if (ret < 0)
546 		return ret;
547 
548 	aq->scr &= ~QSPI_SCR_SCBR_MASK;
549 	aq->scr |= QSPI_SCR_SCBR(scbr);
550 	atmel_qspi_write(aq->scr, aq, QSPI_SCR);
551 
552 	pm_runtime_mark_last_busy(ctrl->dev.parent);
553 	pm_runtime_put_autosuspend(ctrl->dev.parent);
554 
555 	return 0;
556 }
557 
atmel_qspi_set_cs_timing(struct spi_device * spi)558 static int atmel_qspi_set_cs_timing(struct spi_device *spi)
559 {
560 	struct spi_controller *ctrl = spi->controller;
561 	struct atmel_qspi *aq = spi_controller_get_devdata(ctrl);
562 	unsigned long clk_rate;
563 	u32 cs_setup;
564 	int delay;
565 	int ret;
566 
567 	delay = spi_delay_to_ns(&spi->cs_setup, NULL);
568 	if (delay <= 0)
569 		return delay;
570 
571 	clk_rate = clk_get_rate(aq->pclk);
572 	if (!clk_rate)
573 		return -EINVAL;
574 
575 	cs_setup = DIV_ROUND_UP((delay * DIV_ROUND_UP(clk_rate, 1000000)),
576 				1000);
577 
578 	ret = pm_runtime_resume_and_get(ctrl->dev.parent);
579 	if (ret < 0)
580 		return ret;
581 
582 	aq->scr &= ~QSPI_SCR_DLYBS_MASK;
583 	aq->scr |= QSPI_SCR_DLYBS(cs_setup);
584 	atmel_qspi_write(aq->scr, aq, QSPI_SCR);
585 
586 	pm_runtime_mark_last_busy(ctrl->dev.parent);
587 	pm_runtime_put_autosuspend(ctrl->dev.parent);
588 
589 	return 0;
590 }
591 
atmel_qspi_init(struct atmel_qspi * aq)592 static void atmel_qspi_init(struct atmel_qspi *aq)
593 {
594 	/* Reset the QSPI controller */
595 	atmel_qspi_write(QSPI_CR_SWRST, aq, QSPI_CR);
596 
597 	/* Set the QSPI controller by default in Serial Memory Mode */
598 	aq->mr |= QSPI_MR_SMM;
599 	atmel_qspi_write(aq->mr, aq, QSPI_MR);
600 
601 	/* Enable the QSPI controller */
602 	atmel_qspi_write(QSPI_CR_QSPIEN, aq, QSPI_CR);
603 }
604 
atmel_qspi_interrupt(int irq,void * dev_id)605 static irqreturn_t atmel_qspi_interrupt(int irq, void *dev_id)
606 {
607 	struct atmel_qspi *aq = dev_id;
608 	u32 status, mask, pending;
609 
610 	status = atmel_qspi_read(aq, QSPI_SR);
611 	mask = atmel_qspi_read(aq, QSPI_IMR);
612 	pending = status & mask;
613 
614 	if (!pending)
615 		return IRQ_NONE;
616 
617 	aq->pending |= pending;
618 	if ((aq->pending & aq->irq_mask) == aq->irq_mask)
619 		complete(&aq->cmd_completion);
620 
621 	return IRQ_HANDLED;
622 }
623 
624 static const struct atmel_qspi_ops atmel_qspi_ops = {
625 	.set_cfg = atmel_qspi_set_cfg,
626 	.transfer = atmel_qspi_transfer,
627 };
628 
atmel_qspi_probe(struct platform_device * pdev)629 static int atmel_qspi_probe(struct platform_device *pdev)
630 {
631 	struct spi_controller *ctrl;
632 	struct atmel_qspi *aq;
633 	struct resource *res;
634 	int irq, err = 0;
635 
636 	ctrl = devm_spi_alloc_host(&pdev->dev, sizeof(*aq));
637 	if (!ctrl)
638 		return -ENOMEM;
639 
640 	ctrl->mode_bits = SPI_RX_DUAL | SPI_RX_QUAD | SPI_TX_DUAL | SPI_TX_QUAD;
641 	ctrl->setup = atmel_qspi_setup;
642 	ctrl->set_cs_timing = atmel_qspi_set_cs_timing;
643 	ctrl->bus_num = -1;
644 	ctrl->mem_ops = &atmel_qspi_mem_ops;
645 	ctrl->num_chipselect = 1;
646 	ctrl->dev.of_node = pdev->dev.of_node;
647 	platform_set_drvdata(pdev, ctrl);
648 
649 	aq = spi_controller_get_devdata(ctrl);
650 
651 	init_completion(&aq->cmd_completion);
652 	aq->pdev = pdev;
653 	aq->ops = &atmel_qspi_ops;
654 
655 	/* Map the registers */
656 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "qspi_base");
657 	aq->regs = devm_ioremap_resource(&pdev->dev, res);
658 	if (IS_ERR(aq->regs)) {
659 		dev_err(&pdev->dev, "missing registers\n");
660 		return PTR_ERR(aq->regs);
661 	}
662 
663 	/* Map the AHB memory */
664 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "qspi_mmap");
665 	aq->mem = devm_ioremap_resource(&pdev->dev, res);
666 	if (IS_ERR(aq->mem)) {
667 		dev_err(&pdev->dev, "missing AHB memory\n");
668 		return PTR_ERR(aq->mem);
669 	}
670 
671 	aq->mmap_size = resource_size(res);
672 
673 	/* Get the peripheral clock */
674 	aq->pclk = devm_clk_get(&pdev->dev, "pclk");
675 	if (IS_ERR(aq->pclk))
676 		aq->pclk = devm_clk_get(&pdev->dev, NULL);
677 
678 	if (IS_ERR(aq->pclk)) {
679 		dev_err(&pdev->dev, "missing peripheral clock\n");
680 		return PTR_ERR(aq->pclk);
681 	}
682 
683 	/* Enable the peripheral clock */
684 	err = clk_prepare_enable(aq->pclk);
685 	if (err) {
686 		dev_err(&pdev->dev, "failed to enable the peripheral clock\n");
687 		return err;
688 	}
689 
690 	aq->caps = of_device_get_match_data(&pdev->dev);
691 	if (!aq->caps) {
692 		dev_err(&pdev->dev, "Could not retrieve QSPI caps\n");
693 		err = -EINVAL;
694 		goto disable_pclk;
695 	}
696 
697 	if (aq->caps->has_qspick) {
698 		/* Get the QSPI system clock */
699 		aq->qspick = devm_clk_get(&pdev->dev, "qspick");
700 		if (IS_ERR(aq->qspick)) {
701 			dev_err(&pdev->dev, "missing system clock\n");
702 			err = PTR_ERR(aq->qspick);
703 			goto disable_pclk;
704 		}
705 
706 		/* Enable the QSPI system clock */
707 		err = clk_prepare_enable(aq->qspick);
708 		if (err) {
709 			dev_err(&pdev->dev,
710 				"failed to enable the QSPI system clock\n");
711 			goto disable_pclk;
712 		}
713 	}
714 
715 	/* Request the IRQ */
716 	irq = platform_get_irq(pdev, 0);
717 	if (irq < 0) {
718 		err = irq;
719 		goto disable_qspick;
720 	}
721 	err = devm_request_irq(&pdev->dev, irq, atmel_qspi_interrupt,
722 			       0, dev_name(&pdev->dev), aq);
723 	if (err)
724 		goto disable_qspick;
725 
726 	pm_runtime_set_autosuspend_delay(&pdev->dev, 500);
727 	pm_runtime_use_autosuspend(&pdev->dev);
728 	pm_runtime_set_active(&pdev->dev);
729 	pm_runtime_enable(&pdev->dev);
730 	pm_runtime_get_noresume(&pdev->dev);
731 
732 	atmel_qspi_init(aq);
733 
734 	err = spi_register_controller(ctrl);
735 	if (err) {
736 		pm_runtime_put_noidle(&pdev->dev);
737 		pm_runtime_disable(&pdev->dev);
738 		pm_runtime_set_suspended(&pdev->dev);
739 		pm_runtime_dont_use_autosuspend(&pdev->dev);
740 		goto disable_qspick;
741 	}
742 	pm_runtime_mark_last_busy(&pdev->dev);
743 	pm_runtime_put_autosuspend(&pdev->dev);
744 
745 	return 0;
746 
747 disable_qspick:
748 	clk_disable_unprepare(aq->qspick);
749 disable_pclk:
750 	clk_disable_unprepare(aq->pclk);
751 
752 	return err;
753 }
754 
atmel_qspi_remove(struct platform_device * pdev)755 static void atmel_qspi_remove(struct platform_device *pdev)
756 {
757 	struct spi_controller *ctrl = platform_get_drvdata(pdev);
758 	struct atmel_qspi *aq = spi_controller_get_devdata(ctrl);
759 	int ret;
760 
761 	spi_unregister_controller(ctrl);
762 
763 	ret = pm_runtime_get_sync(&pdev->dev);
764 	if (ret >= 0) {
765 		atmel_qspi_write(QSPI_CR_QSPIDIS, aq, QSPI_CR);
766 		clk_disable(aq->qspick);
767 		clk_disable(aq->pclk);
768 	} else {
769 		/*
770 		 * atmel_qspi_runtime_{suspend,resume} just disable and enable
771 		 * the two clks respectively. So after resume failed these are
772 		 * off, and we skip hardware access and disabling these clks again.
773 		 */
774 		dev_warn(&pdev->dev, "Failed to resume device on remove\n");
775 	}
776 
777 	clk_unprepare(aq->qspick);
778 	clk_unprepare(aq->pclk);
779 
780 	pm_runtime_disable(&pdev->dev);
781 	pm_runtime_dont_use_autosuspend(&pdev->dev);
782 	pm_runtime_put_noidle(&pdev->dev);
783 }
784 
atmel_qspi_suspend(struct device * dev)785 static int __maybe_unused atmel_qspi_suspend(struct device *dev)
786 {
787 	struct spi_controller *ctrl = dev_get_drvdata(dev);
788 	struct atmel_qspi *aq = spi_controller_get_devdata(ctrl);
789 	int ret;
790 
791 	ret = pm_runtime_resume_and_get(dev);
792 	if (ret < 0)
793 		return ret;
794 
795 	atmel_qspi_write(QSPI_CR_QSPIDIS, aq, QSPI_CR);
796 
797 	pm_runtime_mark_last_busy(dev);
798 	pm_runtime_force_suspend(dev);
799 
800 	clk_unprepare(aq->qspick);
801 	clk_unprepare(aq->pclk);
802 
803 	return 0;
804 }
805 
atmel_qspi_resume(struct device * dev)806 static int __maybe_unused atmel_qspi_resume(struct device *dev)
807 {
808 	struct spi_controller *ctrl = dev_get_drvdata(dev);
809 	struct atmel_qspi *aq = spi_controller_get_devdata(ctrl);
810 	int ret;
811 
812 	ret = clk_prepare(aq->pclk);
813 	if (ret)
814 		return ret;
815 
816 	ret = clk_prepare(aq->qspick);
817 	if (ret) {
818 		clk_unprepare(aq->pclk);
819 		return ret;
820 	}
821 
822 	ret = pm_runtime_force_resume(dev);
823 	if (ret < 0)
824 		return ret;
825 
826 	atmel_qspi_init(aq);
827 
828 	atmel_qspi_write(aq->scr, aq, QSPI_SCR);
829 
830 	pm_runtime_mark_last_busy(dev);
831 	pm_runtime_put_autosuspend(dev);
832 
833 	return 0;
834 }
835 
atmel_qspi_runtime_suspend(struct device * dev)836 static int __maybe_unused atmel_qspi_runtime_suspend(struct device *dev)
837 {
838 	struct spi_controller *ctrl = dev_get_drvdata(dev);
839 	struct atmel_qspi *aq = spi_controller_get_devdata(ctrl);
840 
841 	clk_disable(aq->qspick);
842 	clk_disable(aq->pclk);
843 
844 	return 0;
845 }
846 
atmel_qspi_runtime_resume(struct device * dev)847 static int __maybe_unused atmel_qspi_runtime_resume(struct device *dev)
848 {
849 	struct spi_controller *ctrl = dev_get_drvdata(dev);
850 	struct atmel_qspi *aq = spi_controller_get_devdata(ctrl);
851 	int ret;
852 
853 	ret = clk_enable(aq->pclk);
854 	if (ret)
855 		return ret;
856 
857 	ret = clk_enable(aq->qspick);
858 	if (ret)
859 		clk_disable(aq->pclk);
860 
861 	return ret;
862 }
863 
864 static const struct dev_pm_ops __maybe_unused atmel_qspi_pm_ops = {
865 	SET_SYSTEM_SLEEP_PM_OPS(atmel_qspi_suspend, atmel_qspi_resume)
866 	SET_RUNTIME_PM_OPS(atmel_qspi_runtime_suspend,
867 			   atmel_qspi_runtime_resume, NULL)
868 };
869 
870 static const struct atmel_qspi_caps atmel_sama5d2_qspi_caps = {};
871 
872 static const struct atmel_qspi_caps atmel_sam9x60_qspi_caps = {
873 	.has_qspick = true,
874 	.has_ricr = true,
875 };
876 
877 static const struct of_device_id atmel_qspi_dt_ids[] = {
878 	{
879 		.compatible = "atmel,sama5d2-qspi",
880 		.data = &atmel_sama5d2_qspi_caps,
881 	},
882 	{
883 		.compatible = "microchip,sam9x60-qspi",
884 		.data = &atmel_sam9x60_qspi_caps,
885 	},
886 	{ /* sentinel */ }
887 };
888 
889 MODULE_DEVICE_TABLE(of, atmel_qspi_dt_ids);
890 
891 static struct platform_driver atmel_qspi_driver = {
892 	.driver = {
893 		.name	= "atmel_qspi",
894 		.of_match_table	= atmel_qspi_dt_ids,
895 		.pm	= pm_ptr(&atmel_qspi_pm_ops),
896 	},
897 	.probe		= atmel_qspi_probe,
898 	.remove_new	= atmel_qspi_remove,
899 };
900 module_platform_driver(atmel_qspi_driver);
901 
902 MODULE_AUTHOR("Cyrille Pitchen <cyrille.pitchen@atmel.com>");
903 MODULE_AUTHOR("Piotr Bugalski <bugalski.piotr@gmail.com");
904 MODULE_DESCRIPTION("Atmel QSPI Controller driver");
905 MODULE_LICENSE("GPL v2");
906