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