1 // SPDX-License-Identifier: GPL-2.0-only
2 //
3 // Driver for Cadence QSPI Controller
4 //
5 // Copyright Altera Corporation (C) 2012-2014. All rights reserved.
6 // Copyright Intel Corporation (C) 2019-2020. All rights reserved.
7 // Copyright (C) 2020 Texas Instruments Incorporated - http://www.ti.com
8
9 #include <linux/clk.h>
10 #include <linux/completion.h>
11 #include <linux/delay.h>
12 #include <linux/dma-mapping.h>
13 #include <linux/dmaengine.h>
14 #include <linux/err.h>
15 #include <linux/errno.h>
16 #include <linux/interrupt.h>
17 #include <linux/io.h>
18 #include <linux/iopoll.h>
19 #include <linux/jiffies.h>
20 #include <linux/kernel.h>
21 #include <linux/module.h>
22 #include <linux/of_device.h>
23 #include <linux/of.h>
24 #include <linux/platform_device.h>
25 #include <linux/pm_runtime.h>
26 #include <linux/reset.h>
27 #include <linux/sched.h>
28 #include <linux/spi/spi.h>
29 #include <linux/spi/spi-mem.h>
30 #include <linux/timer.h>
31
32 #define CQSPI_NAME "cadence-qspi"
33 #define CQSPI_MAX_CHIPSELECT 16
34
35 /* Quirks */
36 #define CQSPI_NEEDS_WR_DELAY BIT(0)
37 #define CQSPI_DISABLE_DAC_MODE BIT(1)
38
39 /* Capabilities */
40 #define CQSPI_SUPPORTS_OCTAL BIT(0)
41
42 struct cqspi_st;
43
44 struct cqspi_flash_pdata {
45 struct cqspi_st *cqspi;
46 u32 clk_rate;
47 u32 read_delay;
48 u32 tshsl_ns;
49 u32 tsd2d_ns;
50 u32 tchsh_ns;
51 u32 tslch_ns;
52 u8 inst_width;
53 u8 addr_width;
54 u8 data_width;
55 bool dtr;
56 u8 cs;
57 };
58
59 struct cqspi_st {
60 struct platform_device *pdev;
61
62 struct clk *clk;
63 unsigned int sclk;
64
65 void __iomem *iobase;
66 void __iomem *ahb_base;
67 resource_size_t ahb_size;
68 struct completion transfer_complete;
69
70 struct dma_chan *rx_chan;
71 struct completion rx_dma_complete;
72 dma_addr_t mmap_phys_base;
73
74 int current_cs;
75 unsigned long master_ref_clk_hz;
76 bool is_decoded_cs;
77 u32 fifo_depth;
78 u32 fifo_width;
79 u32 num_chipselect;
80 bool rclk_en;
81 u32 trigger_address;
82 u32 wr_delay;
83 bool use_direct_mode;
84 struct cqspi_flash_pdata f_pdata[CQSPI_MAX_CHIPSELECT];
85 };
86
87 struct cqspi_driver_platdata {
88 u32 hwcaps_mask;
89 u8 quirks;
90 };
91
92 /* Operation timeout value */
93 #define CQSPI_TIMEOUT_MS 500
94 #define CQSPI_READ_TIMEOUT_MS 10
95
96 /* Instruction type */
97 #define CQSPI_INST_TYPE_SINGLE 0
98 #define CQSPI_INST_TYPE_DUAL 1
99 #define CQSPI_INST_TYPE_QUAD 2
100 #define CQSPI_INST_TYPE_OCTAL 3
101
102 #define CQSPI_DUMMY_CLKS_PER_BYTE 8
103 #define CQSPI_DUMMY_BYTES_MAX 4
104 #define CQSPI_DUMMY_CLKS_MAX 31
105
106 #define CQSPI_STIG_DATA_LEN_MAX 8
107
108 /* Register map */
109 #define CQSPI_REG_CONFIG 0x00
110 #define CQSPI_REG_CONFIG_ENABLE_MASK BIT(0)
111 #define CQSPI_REG_CONFIG_ENB_DIR_ACC_CTRL BIT(7)
112 #define CQSPI_REG_CONFIG_DECODE_MASK BIT(9)
113 #define CQSPI_REG_CONFIG_CHIPSELECT_LSB 10
114 #define CQSPI_REG_CONFIG_DMA_MASK BIT(15)
115 #define CQSPI_REG_CONFIG_BAUD_LSB 19
116 #define CQSPI_REG_CONFIG_DTR_PROTO BIT(24)
117 #define CQSPI_REG_CONFIG_DUAL_OPCODE BIT(30)
118 #define CQSPI_REG_CONFIG_IDLE_LSB 31
119 #define CQSPI_REG_CONFIG_CHIPSELECT_MASK 0xF
120 #define CQSPI_REG_CONFIG_BAUD_MASK 0xF
121
122 #define CQSPI_REG_RD_INSTR 0x04
123 #define CQSPI_REG_RD_INSTR_OPCODE_LSB 0
124 #define CQSPI_REG_RD_INSTR_TYPE_INSTR_LSB 8
125 #define CQSPI_REG_RD_INSTR_TYPE_ADDR_LSB 12
126 #define CQSPI_REG_RD_INSTR_TYPE_DATA_LSB 16
127 #define CQSPI_REG_RD_INSTR_MODE_EN_LSB 20
128 #define CQSPI_REG_RD_INSTR_DUMMY_LSB 24
129 #define CQSPI_REG_RD_INSTR_TYPE_INSTR_MASK 0x3
130 #define CQSPI_REG_RD_INSTR_TYPE_ADDR_MASK 0x3
131 #define CQSPI_REG_RD_INSTR_TYPE_DATA_MASK 0x3
132 #define CQSPI_REG_RD_INSTR_DUMMY_MASK 0x1F
133
134 #define CQSPI_REG_WR_INSTR 0x08
135 #define CQSPI_REG_WR_INSTR_OPCODE_LSB 0
136 #define CQSPI_REG_WR_INSTR_TYPE_ADDR_LSB 12
137 #define CQSPI_REG_WR_INSTR_TYPE_DATA_LSB 16
138
139 #define CQSPI_REG_DELAY 0x0C
140 #define CQSPI_REG_DELAY_TSLCH_LSB 0
141 #define CQSPI_REG_DELAY_TCHSH_LSB 8
142 #define CQSPI_REG_DELAY_TSD2D_LSB 16
143 #define CQSPI_REG_DELAY_TSHSL_LSB 24
144 #define CQSPI_REG_DELAY_TSLCH_MASK 0xFF
145 #define CQSPI_REG_DELAY_TCHSH_MASK 0xFF
146 #define CQSPI_REG_DELAY_TSD2D_MASK 0xFF
147 #define CQSPI_REG_DELAY_TSHSL_MASK 0xFF
148
149 #define CQSPI_REG_READCAPTURE 0x10
150 #define CQSPI_REG_READCAPTURE_BYPASS_LSB 0
151 #define CQSPI_REG_READCAPTURE_DELAY_LSB 1
152 #define CQSPI_REG_READCAPTURE_DELAY_MASK 0xF
153
154 #define CQSPI_REG_SIZE 0x14
155 #define CQSPI_REG_SIZE_ADDRESS_LSB 0
156 #define CQSPI_REG_SIZE_PAGE_LSB 4
157 #define CQSPI_REG_SIZE_BLOCK_LSB 16
158 #define CQSPI_REG_SIZE_ADDRESS_MASK 0xF
159 #define CQSPI_REG_SIZE_PAGE_MASK 0xFFF
160 #define CQSPI_REG_SIZE_BLOCK_MASK 0x3F
161
162 #define CQSPI_REG_SRAMPARTITION 0x18
163 #define CQSPI_REG_INDIRECTTRIGGER 0x1C
164
165 #define CQSPI_REG_DMA 0x20
166 #define CQSPI_REG_DMA_SINGLE_LSB 0
167 #define CQSPI_REG_DMA_BURST_LSB 8
168 #define CQSPI_REG_DMA_SINGLE_MASK 0xFF
169 #define CQSPI_REG_DMA_BURST_MASK 0xFF
170
171 #define CQSPI_REG_REMAP 0x24
172 #define CQSPI_REG_MODE_BIT 0x28
173
174 #define CQSPI_REG_SDRAMLEVEL 0x2C
175 #define CQSPI_REG_SDRAMLEVEL_RD_LSB 0
176 #define CQSPI_REG_SDRAMLEVEL_WR_LSB 16
177 #define CQSPI_REG_SDRAMLEVEL_RD_MASK 0xFFFF
178 #define CQSPI_REG_SDRAMLEVEL_WR_MASK 0xFFFF
179
180 #define CQSPI_REG_WR_COMPLETION_CTRL 0x38
181 #define CQSPI_REG_WR_DISABLE_AUTO_POLL BIT(14)
182
183 #define CQSPI_REG_IRQSTATUS 0x40
184 #define CQSPI_REG_IRQMASK 0x44
185
186 #define CQSPI_REG_INDIRECTRD 0x60
187 #define CQSPI_REG_INDIRECTRD_START_MASK BIT(0)
188 #define CQSPI_REG_INDIRECTRD_CANCEL_MASK BIT(1)
189 #define CQSPI_REG_INDIRECTRD_DONE_MASK BIT(5)
190
191 #define CQSPI_REG_INDIRECTRDWATERMARK 0x64
192 #define CQSPI_REG_INDIRECTRDSTARTADDR 0x68
193 #define CQSPI_REG_INDIRECTRDBYTES 0x6C
194
195 #define CQSPI_REG_CMDCTRL 0x90
196 #define CQSPI_REG_CMDCTRL_EXECUTE_MASK BIT(0)
197 #define CQSPI_REG_CMDCTRL_INPROGRESS_MASK BIT(1)
198 #define CQSPI_REG_CMDCTRL_DUMMY_LSB 7
199 #define CQSPI_REG_CMDCTRL_WR_BYTES_LSB 12
200 #define CQSPI_REG_CMDCTRL_WR_EN_LSB 15
201 #define CQSPI_REG_CMDCTRL_ADD_BYTES_LSB 16
202 #define CQSPI_REG_CMDCTRL_ADDR_EN_LSB 19
203 #define CQSPI_REG_CMDCTRL_RD_BYTES_LSB 20
204 #define CQSPI_REG_CMDCTRL_RD_EN_LSB 23
205 #define CQSPI_REG_CMDCTRL_OPCODE_LSB 24
206 #define CQSPI_REG_CMDCTRL_WR_BYTES_MASK 0x7
207 #define CQSPI_REG_CMDCTRL_ADD_BYTES_MASK 0x3
208 #define CQSPI_REG_CMDCTRL_RD_BYTES_MASK 0x7
209 #define CQSPI_REG_CMDCTRL_DUMMY_MASK 0x1F
210
211 #define CQSPI_REG_INDIRECTWR 0x70
212 #define CQSPI_REG_INDIRECTWR_START_MASK BIT(0)
213 #define CQSPI_REG_INDIRECTWR_CANCEL_MASK BIT(1)
214 #define CQSPI_REG_INDIRECTWR_DONE_MASK BIT(5)
215
216 #define CQSPI_REG_INDIRECTWRWATERMARK 0x74
217 #define CQSPI_REG_INDIRECTWRSTARTADDR 0x78
218 #define CQSPI_REG_INDIRECTWRBYTES 0x7C
219
220 #define CQSPI_REG_CMDADDRESS 0x94
221 #define CQSPI_REG_CMDREADDATALOWER 0xA0
222 #define CQSPI_REG_CMDREADDATAUPPER 0xA4
223 #define CQSPI_REG_CMDWRITEDATALOWER 0xA8
224 #define CQSPI_REG_CMDWRITEDATAUPPER 0xAC
225
226 #define CQSPI_REG_POLLING_STATUS 0xB0
227 #define CQSPI_REG_POLLING_STATUS_DUMMY_LSB 16
228
229 #define CQSPI_REG_OP_EXT_LOWER 0xE0
230 #define CQSPI_REG_OP_EXT_READ_LSB 24
231 #define CQSPI_REG_OP_EXT_WRITE_LSB 16
232 #define CQSPI_REG_OP_EXT_STIG_LSB 0
233
234 /* Interrupt status bits */
235 #define CQSPI_REG_IRQ_MODE_ERR BIT(0)
236 #define CQSPI_REG_IRQ_UNDERFLOW BIT(1)
237 #define CQSPI_REG_IRQ_IND_COMP BIT(2)
238 #define CQSPI_REG_IRQ_IND_RD_REJECT BIT(3)
239 #define CQSPI_REG_IRQ_WR_PROTECTED_ERR BIT(4)
240 #define CQSPI_REG_IRQ_ILLEGAL_AHB_ERR BIT(5)
241 #define CQSPI_REG_IRQ_WATERMARK BIT(6)
242 #define CQSPI_REG_IRQ_IND_SRAM_FULL BIT(12)
243
244 #define CQSPI_IRQ_MASK_RD (CQSPI_REG_IRQ_WATERMARK | \
245 CQSPI_REG_IRQ_IND_SRAM_FULL | \
246 CQSPI_REG_IRQ_IND_COMP)
247
248 #define CQSPI_IRQ_MASK_WR (CQSPI_REG_IRQ_IND_COMP | \
249 CQSPI_REG_IRQ_WATERMARK | \
250 CQSPI_REG_IRQ_UNDERFLOW)
251
252 #define CQSPI_IRQ_STATUS_MASK 0x1FFFF
253
cqspi_wait_for_bit(void __iomem * reg,const u32 mask,bool clr)254 static int cqspi_wait_for_bit(void __iomem *reg, const u32 mask, bool clr)
255 {
256 u32 val;
257
258 return readl_relaxed_poll_timeout(reg, val,
259 (((clr ? ~val : val) & mask) == mask),
260 10, CQSPI_TIMEOUT_MS * 1000);
261 }
262
cqspi_is_idle(struct cqspi_st * cqspi)263 static bool cqspi_is_idle(struct cqspi_st *cqspi)
264 {
265 u32 reg = readl(cqspi->iobase + CQSPI_REG_CONFIG);
266
267 return reg & (1UL << CQSPI_REG_CONFIG_IDLE_LSB);
268 }
269
cqspi_get_rd_sram_level(struct cqspi_st * cqspi)270 static u32 cqspi_get_rd_sram_level(struct cqspi_st *cqspi)
271 {
272 u32 reg = readl(cqspi->iobase + CQSPI_REG_SDRAMLEVEL);
273
274 reg >>= CQSPI_REG_SDRAMLEVEL_RD_LSB;
275 return reg & CQSPI_REG_SDRAMLEVEL_RD_MASK;
276 }
277
cqspi_irq_handler(int this_irq,void * dev)278 static irqreturn_t cqspi_irq_handler(int this_irq, void *dev)
279 {
280 struct cqspi_st *cqspi = dev;
281 unsigned int irq_status;
282
283 /* Read interrupt status */
284 irq_status = readl(cqspi->iobase + CQSPI_REG_IRQSTATUS);
285
286 /* Clear interrupt */
287 writel(irq_status, cqspi->iobase + CQSPI_REG_IRQSTATUS);
288
289 irq_status &= CQSPI_IRQ_MASK_RD | CQSPI_IRQ_MASK_WR;
290
291 if (irq_status)
292 complete(&cqspi->transfer_complete);
293
294 return IRQ_HANDLED;
295 }
296
cqspi_calc_rdreg(struct cqspi_flash_pdata * f_pdata)297 static unsigned int cqspi_calc_rdreg(struct cqspi_flash_pdata *f_pdata)
298 {
299 u32 rdreg = 0;
300
301 rdreg |= f_pdata->inst_width << CQSPI_REG_RD_INSTR_TYPE_INSTR_LSB;
302 rdreg |= f_pdata->addr_width << CQSPI_REG_RD_INSTR_TYPE_ADDR_LSB;
303 rdreg |= f_pdata->data_width << CQSPI_REG_RD_INSTR_TYPE_DATA_LSB;
304
305 return rdreg;
306 }
307
cqspi_calc_dummy(const struct spi_mem_op * op,bool dtr)308 static unsigned int cqspi_calc_dummy(const struct spi_mem_op *op, bool dtr)
309 {
310 unsigned int dummy_clk;
311
312 if (!op->dummy.nbytes)
313 return 0;
314
315 dummy_clk = op->dummy.nbytes * (8 / op->dummy.buswidth);
316 if (dtr)
317 dummy_clk /= 2;
318
319 return dummy_clk;
320 }
321
cqspi_set_protocol(struct cqspi_flash_pdata * f_pdata,const struct spi_mem_op * op)322 static int cqspi_set_protocol(struct cqspi_flash_pdata *f_pdata,
323 const struct spi_mem_op *op)
324 {
325 f_pdata->inst_width = CQSPI_INST_TYPE_SINGLE;
326 f_pdata->addr_width = CQSPI_INST_TYPE_SINGLE;
327 f_pdata->data_width = CQSPI_INST_TYPE_SINGLE;
328
329 /*
330 * For an op to be DTR, cmd phase along with every other non-empty
331 * phase should have dtr field set to 1. If an op phase has zero
332 * nbytes, ignore its dtr field; otherwise, check its dtr field.
333 */
334 f_pdata->dtr = op->cmd.dtr &&
335 (!op->addr.nbytes || op->addr.dtr) &&
336 (!op->data.nbytes || op->data.dtr);
337
338 switch (op->data.buswidth) {
339 case 0:
340 break;
341 case 1:
342 f_pdata->data_width = CQSPI_INST_TYPE_SINGLE;
343 break;
344 case 2:
345 f_pdata->data_width = CQSPI_INST_TYPE_DUAL;
346 break;
347 case 4:
348 f_pdata->data_width = CQSPI_INST_TYPE_QUAD;
349 break;
350 case 8:
351 f_pdata->data_width = CQSPI_INST_TYPE_OCTAL;
352 break;
353 default:
354 return -EINVAL;
355 }
356
357 /* Right now we only support 8-8-8 DTR mode. */
358 if (f_pdata->dtr) {
359 switch (op->cmd.buswidth) {
360 case 0:
361 break;
362 case 8:
363 f_pdata->inst_width = CQSPI_INST_TYPE_OCTAL;
364 break;
365 default:
366 return -EINVAL;
367 }
368
369 switch (op->addr.buswidth) {
370 case 0:
371 break;
372 case 8:
373 f_pdata->addr_width = CQSPI_INST_TYPE_OCTAL;
374 break;
375 default:
376 return -EINVAL;
377 }
378
379 switch (op->data.buswidth) {
380 case 0:
381 break;
382 case 8:
383 f_pdata->data_width = CQSPI_INST_TYPE_OCTAL;
384 break;
385 default:
386 return -EINVAL;
387 }
388 }
389
390 return 0;
391 }
392
cqspi_wait_idle(struct cqspi_st * cqspi)393 static int cqspi_wait_idle(struct cqspi_st *cqspi)
394 {
395 const unsigned int poll_idle_retry = 3;
396 unsigned int count = 0;
397 unsigned long timeout;
398
399 timeout = jiffies + msecs_to_jiffies(CQSPI_TIMEOUT_MS);
400 while (1) {
401 /*
402 * Read few times in succession to ensure the controller
403 * is indeed idle, that is, the bit does not transition
404 * low again.
405 */
406 if (cqspi_is_idle(cqspi))
407 count++;
408 else
409 count = 0;
410
411 if (count >= poll_idle_retry)
412 return 0;
413
414 if (time_after(jiffies, timeout)) {
415 /* Timeout, in busy mode. */
416 dev_err(&cqspi->pdev->dev,
417 "QSPI is still busy after %dms timeout.\n",
418 CQSPI_TIMEOUT_MS);
419 return -ETIMEDOUT;
420 }
421
422 cpu_relax();
423 }
424 }
425
cqspi_exec_flash_cmd(struct cqspi_st * cqspi,unsigned int reg)426 static int cqspi_exec_flash_cmd(struct cqspi_st *cqspi, unsigned int reg)
427 {
428 void __iomem *reg_base = cqspi->iobase;
429 int ret;
430
431 /* Write the CMDCTRL without start execution. */
432 writel(reg, reg_base + CQSPI_REG_CMDCTRL);
433 /* Start execute */
434 reg |= CQSPI_REG_CMDCTRL_EXECUTE_MASK;
435 writel(reg, reg_base + CQSPI_REG_CMDCTRL);
436
437 /* Polling for completion. */
438 ret = cqspi_wait_for_bit(reg_base + CQSPI_REG_CMDCTRL,
439 CQSPI_REG_CMDCTRL_INPROGRESS_MASK, 1);
440 if (ret) {
441 dev_err(&cqspi->pdev->dev,
442 "Flash command execution timed out.\n");
443 return ret;
444 }
445
446 /* Polling QSPI idle status. */
447 return cqspi_wait_idle(cqspi);
448 }
449
cqspi_setup_opcode_ext(struct cqspi_flash_pdata * f_pdata,const struct spi_mem_op * op,unsigned int shift)450 static int cqspi_setup_opcode_ext(struct cqspi_flash_pdata *f_pdata,
451 const struct spi_mem_op *op,
452 unsigned int shift)
453 {
454 struct cqspi_st *cqspi = f_pdata->cqspi;
455 void __iomem *reg_base = cqspi->iobase;
456 unsigned int reg;
457 u8 ext;
458
459 if (op->cmd.nbytes != 2)
460 return -EINVAL;
461
462 /* Opcode extension is the LSB. */
463 ext = op->cmd.opcode & 0xff;
464
465 reg = readl(reg_base + CQSPI_REG_OP_EXT_LOWER);
466 reg &= ~(0xff << shift);
467 reg |= ext << shift;
468 writel(reg, reg_base + CQSPI_REG_OP_EXT_LOWER);
469
470 return 0;
471 }
472
cqspi_enable_dtr(struct cqspi_flash_pdata * f_pdata,const struct spi_mem_op * op,unsigned int shift,bool enable)473 static int cqspi_enable_dtr(struct cqspi_flash_pdata *f_pdata,
474 const struct spi_mem_op *op, unsigned int shift,
475 bool enable)
476 {
477 struct cqspi_st *cqspi = f_pdata->cqspi;
478 void __iomem *reg_base = cqspi->iobase;
479 unsigned int reg;
480 int ret;
481
482 reg = readl(reg_base + CQSPI_REG_CONFIG);
483
484 /*
485 * We enable dual byte opcode here. The callers have to set up the
486 * extension opcode based on which type of operation it is.
487 */
488 if (enable) {
489 reg |= CQSPI_REG_CONFIG_DTR_PROTO;
490 reg |= CQSPI_REG_CONFIG_DUAL_OPCODE;
491
492 /* Set up command opcode extension. */
493 ret = cqspi_setup_opcode_ext(f_pdata, op, shift);
494 if (ret)
495 return ret;
496 } else {
497 reg &= ~CQSPI_REG_CONFIG_DTR_PROTO;
498 reg &= ~CQSPI_REG_CONFIG_DUAL_OPCODE;
499 }
500
501 writel(reg, reg_base + CQSPI_REG_CONFIG);
502
503 return cqspi_wait_idle(cqspi);
504 }
505
cqspi_command_read(struct cqspi_flash_pdata * f_pdata,const struct spi_mem_op * op)506 static int cqspi_command_read(struct cqspi_flash_pdata *f_pdata,
507 const struct spi_mem_op *op)
508 {
509 struct cqspi_st *cqspi = f_pdata->cqspi;
510 void __iomem *reg_base = cqspi->iobase;
511 u8 *rxbuf = op->data.buf.in;
512 u8 opcode;
513 size_t n_rx = op->data.nbytes;
514 unsigned int rdreg;
515 unsigned int reg;
516 unsigned int dummy_clk;
517 size_t read_len;
518 int status;
519
520 status = cqspi_set_protocol(f_pdata, op);
521 if (status)
522 return status;
523
524 status = cqspi_enable_dtr(f_pdata, op, CQSPI_REG_OP_EXT_STIG_LSB,
525 f_pdata->dtr);
526 if (status)
527 return status;
528
529 if (!n_rx || n_rx > CQSPI_STIG_DATA_LEN_MAX || !rxbuf) {
530 dev_err(&cqspi->pdev->dev,
531 "Invalid input argument, len %zu rxbuf 0x%p\n",
532 n_rx, rxbuf);
533 return -EINVAL;
534 }
535
536 if (f_pdata->dtr)
537 opcode = op->cmd.opcode >> 8;
538 else
539 opcode = op->cmd.opcode;
540
541 reg = opcode << CQSPI_REG_CMDCTRL_OPCODE_LSB;
542
543 rdreg = cqspi_calc_rdreg(f_pdata);
544 writel(rdreg, reg_base + CQSPI_REG_RD_INSTR);
545
546 dummy_clk = cqspi_calc_dummy(op, f_pdata->dtr);
547 if (dummy_clk > CQSPI_DUMMY_CLKS_MAX)
548 return -EOPNOTSUPP;
549
550 if (dummy_clk)
551 reg |= (dummy_clk & CQSPI_REG_CMDCTRL_DUMMY_MASK)
552 << CQSPI_REG_CMDCTRL_DUMMY_LSB;
553
554 reg |= (0x1 << CQSPI_REG_CMDCTRL_RD_EN_LSB);
555
556 /* 0 means 1 byte. */
557 reg |= (((n_rx - 1) & CQSPI_REG_CMDCTRL_RD_BYTES_MASK)
558 << CQSPI_REG_CMDCTRL_RD_BYTES_LSB);
559 status = cqspi_exec_flash_cmd(cqspi, reg);
560 if (status)
561 return status;
562
563 reg = readl(reg_base + CQSPI_REG_CMDREADDATALOWER);
564
565 /* Put the read value into rx_buf */
566 read_len = (n_rx > 4) ? 4 : n_rx;
567 memcpy(rxbuf, ®, read_len);
568 rxbuf += read_len;
569
570 if (n_rx > 4) {
571 reg = readl(reg_base + CQSPI_REG_CMDREADDATAUPPER);
572
573 read_len = n_rx - read_len;
574 memcpy(rxbuf, ®, read_len);
575 }
576
577 return 0;
578 }
579
cqspi_command_write(struct cqspi_flash_pdata * f_pdata,const struct spi_mem_op * op)580 static int cqspi_command_write(struct cqspi_flash_pdata *f_pdata,
581 const struct spi_mem_op *op)
582 {
583 struct cqspi_st *cqspi = f_pdata->cqspi;
584 void __iomem *reg_base = cqspi->iobase;
585 u8 opcode;
586 const u8 *txbuf = op->data.buf.out;
587 size_t n_tx = op->data.nbytes;
588 unsigned int reg;
589 unsigned int data;
590 size_t write_len;
591 int ret;
592
593 ret = cqspi_set_protocol(f_pdata, op);
594 if (ret)
595 return ret;
596
597 ret = cqspi_enable_dtr(f_pdata, op, CQSPI_REG_OP_EXT_STIG_LSB,
598 f_pdata->dtr);
599 if (ret)
600 return ret;
601
602 if (n_tx > CQSPI_STIG_DATA_LEN_MAX || (n_tx && !txbuf)) {
603 dev_err(&cqspi->pdev->dev,
604 "Invalid input argument, cmdlen %zu txbuf 0x%p\n",
605 n_tx, txbuf);
606 return -EINVAL;
607 }
608
609 reg = cqspi_calc_rdreg(f_pdata);
610 writel(reg, reg_base + CQSPI_REG_RD_INSTR);
611
612 if (f_pdata->dtr)
613 opcode = op->cmd.opcode >> 8;
614 else
615 opcode = op->cmd.opcode;
616
617 reg = opcode << CQSPI_REG_CMDCTRL_OPCODE_LSB;
618
619 if (op->addr.nbytes) {
620 reg |= (0x1 << CQSPI_REG_CMDCTRL_ADDR_EN_LSB);
621 reg |= ((op->addr.nbytes - 1) &
622 CQSPI_REG_CMDCTRL_ADD_BYTES_MASK)
623 << CQSPI_REG_CMDCTRL_ADD_BYTES_LSB;
624
625 writel(op->addr.val, reg_base + CQSPI_REG_CMDADDRESS);
626 }
627
628 if (n_tx) {
629 reg |= (0x1 << CQSPI_REG_CMDCTRL_WR_EN_LSB);
630 reg |= ((n_tx - 1) & CQSPI_REG_CMDCTRL_WR_BYTES_MASK)
631 << CQSPI_REG_CMDCTRL_WR_BYTES_LSB;
632 data = 0;
633 write_len = (n_tx > 4) ? 4 : n_tx;
634 memcpy(&data, txbuf, write_len);
635 txbuf += write_len;
636 writel(data, reg_base + CQSPI_REG_CMDWRITEDATALOWER);
637
638 if (n_tx > 4) {
639 data = 0;
640 write_len = n_tx - 4;
641 memcpy(&data, txbuf, write_len);
642 writel(data, reg_base + CQSPI_REG_CMDWRITEDATAUPPER);
643 }
644 }
645
646 return cqspi_exec_flash_cmd(cqspi, reg);
647 }
648
cqspi_read_setup(struct cqspi_flash_pdata * f_pdata,const struct spi_mem_op * op)649 static int cqspi_read_setup(struct cqspi_flash_pdata *f_pdata,
650 const struct spi_mem_op *op)
651 {
652 struct cqspi_st *cqspi = f_pdata->cqspi;
653 void __iomem *reg_base = cqspi->iobase;
654 unsigned int dummy_clk = 0;
655 unsigned int reg;
656 int ret;
657 u8 opcode;
658
659 ret = cqspi_enable_dtr(f_pdata, op, CQSPI_REG_OP_EXT_READ_LSB,
660 f_pdata->dtr);
661 if (ret)
662 return ret;
663
664 if (f_pdata->dtr)
665 opcode = op->cmd.opcode >> 8;
666 else
667 opcode = op->cmd.opcode;
668
669 reg = opcode << CQSPI_REG_RD_INSTR_OPCODE_LSB;
670 reg |= cqspi_calc_rdreg(f_pdata);
671
672 /* Setup dummy clock cycles */
673 dummy_clk = cqspi_calc_dummy(op, f_pdata->dtr);
674
675 if (dummy_clk > CQSPI_DUMMY_CLKS_MAX)
676 return -EOPNOTSUPP;
677
678 if (dummy_clk)
679 reg |= (dummy_clk & CQSPI_REG_RD_INSTR_DUMMY_MASK)
680 << CQSPI_REG_RD_INSTR_DUMMY_LSB;
681
682 writel(reg, reg_base + CQSPI_REG_RD_INSTR);
683
684 /* Set address width */
685 reg = readl(reg_base + CQSPI_REG_SIZE);
686 reg &= ~CQSPI_REG_SIZE_ADDRESS_MASK;
687 reg |= (op->addr.nbytes - 1);
688 writel(reg, reg_base + CQSPI_REG_SIZE);
689 return 0;
690 }
691
cqspi_indirect_read_execute(struct cqspi_flash_pdata * f_pdata,u8 * rxbuf,loff_t from_addr,const size_t n_rx)692 static int cqspi_indirect_read_execute(struct cqspi_flash_pdata *f_pdata,
693 u8 *rxbuf, loff_t from_addr,
694 const size_t n_rx)
695 {
696 struct cqspi_st *cqspi = f_pdata->cqspi;
697 struct device *dev = &cqspi->pdev->dev;
698 void __iomem *reg_base = cqspi->iobase;
699 void __iomem *ahb_base = cqspi->ahb_base;
700 unsigned int remaining = n_rx;
701 unsigned int mod_bytes = n_rx % 4;
702 unsigned int bytes_to_read = 0;
703 u8 *rxbuf_end = rxbuf + n_rx;
704 int ret = 0;
705
706 writel(from_addr, reg_base + CQSPI_REG_INDIRECTRDSTARTADDR);
707 writel(remaining, reg_base + CQSPI_REG_INDIRECTRDBYTES);
708
709 /* Clear all interrupts. */
710 writel(CQSPI_IRQ_STATUS_MASK, reg_base + CQSPI_REG_IRQSTATUS);
711
712 writel(CQSPI_IRQ_MASK_RD, reg_base + CQSPI_REG_IRQMASK);
713
714 reinit_completion(&cqspi->transfer_complete);
715 writel(CQSPI_REG_INDIRECTRD_START_MASK,
716 reg_base + CQSPI_REG_INDIRECTRD);
717
718 while (remaining > 0) {
719 if (!wait_for_completion_timeout(&cqspi->transfer_complete,
720 msecs_to_jiffies(CQSPI_READ_TIMEOUT_MS)))
721 ret = -ETIMEDOUT;
722
723 bytes_to_read = cqspi_get_rd_sram_level(cqspi);
724
725 if (ret && bytes_to_read == 0) {
726 dev_err(dev, "Indirect read timeout, no bytes\n");
727 goto failrd;
728 }
729
730 while (bytes_to_read != 0) {
731 unsigned int word_remain = round_down(remaining, 4);
732
733 bytes_to_read *= cqspi->fifo_width;
734 bytes_to_read = bytes_to_read > remaining ?
735 remaining : bytes_to_read;
736 bytes_to_read = round_down(bytes_to_read, 4);
737 /* Read 4 byte word chunks then single bytes */
738 if (bytes_to_read) {
739 ioread32_rep(ahb_base, rxbuf,
740 (bytes_to_read / 4));
741 } else if (!word_remain && mod_bytes) {
742 unsigned int temp = ioread32(ahb_base);
743
744 bytes_to_read = mod_bytes;
745 memcpy(rxbuf, &temp, min((unsigned int)
746 (rxbuf_end - rxbuf),
747 bytes_to_read));
748 }
749 rxbuf += bytes_to_read;
750 remaining -= bytes_to_read;
751 bytes_to_read = cqspi_get_rd_sram_level(cqspi);
752 }
753
754 if (remaining > 0)
755 reinit_completion(&cqspi->transfer_complete);
756 }
757
758 /* Check indirect done status */
759 ret = cqspi_wait_for_bit(reg_base + CQSPI_REG_INDIRECTRD,
760 CQSPI_REG_INDIRECTRD_DONE_MASK, 0);
761 if (ret) {
762 dev_err(dev, "Indirect read completion error (%i)\n", ret);
763 goto failrd;
764 }
765
766 /* Disable interrupt */
767 writel(0, reg_base + CQSPI_REG_IRQMASK);
768
769 /* Clear indirect completion status */
770 writel(CQSPI_REG_INDIRECTRD_DONE_MASK, reg_base + CQSPI_REG_INDIRECTRD);
771
772 return 0;
773
774 failrd:
775 /* Disable interrupt */
776 writel(0, reg_base + CQSPI_REG_IRQMASK);
777
778 /* Cancel the indirect read */
779 writel(CQSPI_REG_INDIRECTWR_CANCEL_MASK,
780 reg_base + CQSPI_REG_INDIRECTRD);
781 return ret;
782 }
783
cqspi_write_setup(struct cqspi_flash_pdata * f_pdata,const struct spi_mem_op * op)784 static int cqspi_write_setup(struct cqspi_flash_pdata *f_pdata,
785 const struct spi_mem_op *op)
786 {
787 unsigned int reg;
788 int ret;
789 struct cqspi_st *cqspi = f_pdata->cqspi;
790 void __iomem *reg_base = cqspi->iobase;
791 u8 opcode;
792
793 ret = cqspi_enable_dtr(f_pdata, op, CQSPI_REG_OP_EXT_WRITE_LSB,
794 f_pdata->dtr);
795 if (ret)
796 return ret;
797
798 if (f_pdata->dtr)
799 opcode = op->cmd.opcode >> 8;
800 else
801 opcode = op->cmd.opcode;
802
803 /* Set opcode. */
804 reg = opcode << CQSPI_REG_WR_INSTR_OPCODE_LSB;
805 reg |= f_pdata->data_width << CQSPI_REG_WR_INSTR_TYPE_DATA_LSB;
806 reg |= f_pdata->addr_width << CQSPI_REG_WR_INSTR_TYPE_ADDR_LSB;
807 writel(reg, reg_base + CQSPI_REG_WR_INSTR);
808 reg = cqspi_calc_rdreg(f_pdata);
809 writel(reg, reg_base + CQSPI_REG_RD_INSTR);
810
811 /*
812 * SPI NAND flashes require the address of the status register to be
813 * passed in the Read SR command. Also, some SPI NOR flashes like the
814 * cypress Semper flash expect a 4-byte dummy address in the Read SR
815 * command in DTR mode.
816 *
817 * But this controller does not support address phase in the Read SR
818 * command when doing auto-HW polling. So, disable write completion
819 * polling on the controller's side. spinand and spi-nor will take
820 * care of polling the status register.
821 */
822 reg = readl(reg_base + CQSPI_REG_WR_COMPLETION_CTRL);
823 reg |= CQSPI_REG_WR_DISABLE_AUTO_POLL;
824 writel(reg, reg_base + CQSPI_REG_WR_COMPLETION_CTRL);
825
826 reg = readl(reg_base + CQSPI_REG_SIZE);
827 reg &= ~CQSPI_REG_SIZE_ADDRESS_MASK;
828 reg |= (op->addr.nbytes - 1);
829 writel(reg, reg_base + CQSPI_REG_SIZE);
830 return 0;
831 }
832
cqspi_indirect_write_execute(struct cqspi_flash_pdata * f_pdata,loff_t to_addr,const u8 * txbuf,const size_t n_tx)833 static int cqspi_indirect_write_execute(struct cqspi_flash_pdata *f_pdata,
834 loff_t to_addr, const u8 *txbuf,
835 const size_t n_tx)
836 {
837 struct cqspi_st *cqspi = f_pdata->cqspi;
838 struct device *dev = &cqspi->pdev->dev;
839 void __iomem *reg_base = cqspi->iobase;
840 unsigned int remaining = n_tx;
841 unsigned int write_bytes;
842 int ret;
843
844 writel(to_addr, reg_base + CQSPI_REG_INDIRECTWRSTARTADDR);
845 writel(remaining, reg_base + CQSPI_REG_INDIRECTWRBYTES);
846
847 /* Clear all interrupts. */
848 writel(CQSPI_IRQ_STATUS_MASK, reg_base + CQSPI_REG_IRQSTATUS);
849
850 writel(CQSPI_IRQ_MASK_WR, reg_base + CQSPI_REG_IRQMASK);
851
852 reinit_completion(&cqspi->transfer_complete);
853 writel(CQSPI_REG_INDIRECTWR_START_MASK,
854 reg_base + CQSPI_REG_INDIRECTWR);
855 /*
856 * As per 66AK2G02 TRM SPRUHY8F section 11.15.5.3 Indirect Access
857 * Controller programming sequence, couple of cycles of
858 * QSPI_REF_CLK delay is required for the above bit to
859 * be internally synchronized by the QSPI module. Provide 5
860 * cycles of delay.
861 */
862 if (cqspi->wr_delay)
863 ndelay(cqspi->wr_delay);
864
865 while (remaining > 0) {
866 size_t write_words, mod_bytes;
867
868 write_bytes = remaining;
869 write_words = write_bytes / 4;
870 mod_bytes = write_bytes % 4;
871 /* Write 4 bytes at a time then single bytes. */
872 if (write_words) {
873 iowrite32_rep(cqspi->ahb_base, txbuf, write_words);
874 txbuf += (write_words * 4);
875 }
876 if (mod_bytes) {
877 unsigned int temp = 0xFFFFFFFF;
878
879 memcpy(&temp, txbuf, mod_bytes);
880 iowrite32(temp, cqspi->ahb_base);
881 txbuf += mod_bytes;
882 }
883
884 if (!wait_for_completion_timeout(&cqspi->transfer_complete,
885 msecs_to_jiffies(CQSPI_TIMEOUT_MS))) {
886 dev_err(dev, "Indirect write timeout\n");
887 ret = -ETIMEDOUT;
888 goto failwr;
889 }
890
891 remaining -= write_bytes;
892
893 if (remaining > 0)
894 reinit_completion(&cqspi->transfer_complete);
895 }
896
897 /* Check indirect done status */
898 ret = cqspi_wait_for_bit(reg_base + CQSPI_REG_INDIRECTWR,
899 CQSPI_REG_INDIRECTWR_DONE_MASK, 0);
900 if (ret) {
901 dev_err(dev, "Indirect write completion error (%i)\n", ret);
902 goto failwr;
903 }
904
905 /* Disable interrupt. */
906 writel(0, reg_base + CQSPI_REG_IRQMASK);
907
908 /* Clear indirect completion status */
909 writel(CQSPI_REG_INDIRECTWR_DONE_MASK, reg_base + CQSPI_REG_INDIRECTWR);
910
911 cqspi_wait_idle(cqspi);
912
913 return 0;
914
915 failwr:
916 /* Disable interrupt. */
917 writel(0, reg_base + CQSPI_REG_IRQMASK);
918
919 /* Cancel the indirect write */
920 writel(CQSPI_REG_INDIRECTWR_CANCEL_MASK,
921 reg_base + CQSPI_REG_INDIRECTWR);
922 return ret;
923 }
924
cqspi_chipselect(struct cqspi_flash_pdata * f_pdata)925 static void cqspi_chipselect(struct cqspi_flash_pdata *f_pdata)
926 {
927 struct cqspi_st *cqspi = f_pdata->cqspi;
928 void __iomem *reg_base = cqspi->iobase;
929 unsigned int chip_select = f_pdata->cs;
930 unsigned int reg;
931
932 reg = readl(reg_base + CQSPI_REG_CONFIG);
933 if (cqspi->is_decoded_cs) {
934 reg |= CQSPI_REG_CONFIG_DECODE_MASK;
935 } else {
936 reg &= ~CQSPI_REG_CONFIG_DECODE_MASK;
937
938 /* Convert CS if without decoder.
939 * CS0 to 4b'1110
940 * CS1 to 4b'1101
941 * CS2 to 4b'1011
942 * CS3 to 4b'0111
943 */
944 chip_select = 0xF & ~(1 << chip_select);
945 }
946
947 reg &= ~(CQSPI_REG_CONFIG_CHIPSELECT_MASK
948 << CQSPI_REG_CONFIG_CHIPSELECT_LSB);
949 reg |= (chip_select & CQSPI_REG_CONFIG_CHIPSELECT_MASK)
950 << CQSPI_REG_CONFIG_CHIPSELECT_LSB;
951 writel(reg, reg_base + CQSPI_REG_CONFIG);
952 }
953
calculate_ticks_for_ns(const unsigned int ref_clk_hz,const unsigned int ns_val)954 static unsigned int calculate_ticks_for_ns(const unsigned int ref_clk_hz,
955 const unsigned int ns_val)
956 {
957 unsigned int ticks;
958
959 ticks = ref_clk_hz / 1000; /* kHz */
960 ticks = DIV_ROUND_UP(ticks * ns_val, 1000000);
961
962 return ticks;
963 }
964
cqspi_delay(struct cqspi_flash_pdata * f_pdata)965 static void cqspi_delay(struct cqspi_flash_pdata *f_pdata)
966 {
967 struct cqspi_st *cqspi = f_pdata->cqspi;
968 void __iomem *iobase = cqspi->iobase;
969 const unsigned int ref_clk_hz = cqspi->master_ref_clk_hz;
970 unsigned int tshsl, tchsh, tslch, tsd2d;
971 unsigned int reg;
972 unsigned int tsclk;
973
974 /* calculate the number of ref ticks for one sclk tick */
975 tsclk = DIV_ROUND_UP(ref_clk_hz, cqspi->sclk);
976
977 tshsl = calculate_ticks_for_ns(ref_clk_hz, f_pdata->tshsl_ns);
978 /* this particular value must be at least one sclk */
979 if (tshsl < tsclk)
980 tshsl = tsclk;
981
982 tchsh = calculate_ticks_for_ns(ref_clk_hz, f_pdata->tchsh_ns);
983 tslch = calculate_ticks_for_ns(ref_clk_hz, f_pdata->tslch_ns);
984 tsd2d = calculate_ticks_for_ns(ref_clk_hz, f_pdata->tsd2d_ns);
985
986 reg = (tshsl & CQSPI_REG_DELAY_TSHSL_MASK)
987 << CQSPI_REG_DELAY_TSHSL_LSB;
988 reg |= (tchsh & CQSPI_REG_DELAY_TCHSH_MASK)
989 << CQSPI_REG_DELAY_TCHSH_LSB;
990 reg |= (tslch & CQSPI_REG_DELAY_TSLCH_MASK)
991 << CQSPI_REG_DELAY_TSLCH_LSB;
992 reg |= (tsd2d & CQSPI_REG_DELAY_TSD2D_MASK)
993 << CQSPI_REG_DELAY_TSD2D_LSB;
994 writel(reg, iobase + CQSPI_REG_DELAY);
995 }
996
cqspi_config_baudrate_div(struct cqspi_st * cqspi)997 static void cqspi_config_baudrate_div(struct cqspi_st *cqspi)
998 {
999 const unsigned int ref_clk_hz = cqspi->master_ref_clk_hz;
1000 void __iomem *reg_base = cqspi->iobase;
1001 u32 reg, div;
1002
1003 /* Recalculate the baudrate divisor based on QSPI specification. */
1004 div = DIV_ROUND_UP(ref_clk_hz, 2 * cqspi->sclk) - 1;
1005
1006 reg = readl(reg_base + CQSPI_REG_CONFIG);
1007 reg &= ~(CQSPI_REG_CONFIG_BAUD_MASK << CQSPI_REG_CONFIG_BAUD_LSB);
1008 reg |= (div & CQSPI_REG_CONFIG_BAUD_MASK) << CQSPI_REG_CONFIG_BAUD_LSB;
1009 writel(reg, reg_base + CQSPI_REG_CONFIG);
1010 }
1011
cqspi_readdata_capture(struct cqspi_st * cqspi,const bool bypass,const unsigned int delay)1012 static void cqspi_readdata_capture(struct cqspi_st *cqspi,
1013 const bool bypass,
1014 const unsigned int delay)
1015 {
1016 void __iomem *reg_base = cqspi->iobase;
1017 unsigned int reg;
1018
1019 reg = readl(reg_base + CQSPI_REG_READCAPTURE);
1020
1021 if (bypass)
1022 reg |= (1 << CQSPI_REG_READCAPTURE_BYPASS_LSB);
1023 else
1024 reg &= ~(1 << CQSPI_REG_READCAPTURE_BYPASS_LSB);
1025
1026 reg &= ~(CQSPI_REG_READCAPTURE_DELAY_MASK
1027 << CQSPI_REG_READCAPTURE_DELAY_LSB);
1028
1029 reg |= (delay & CQSPI_REG_READCAPTURE_DELAY_MASK)
1030 << CQSPI_REG_READCAPTURE_DELAY_LSB;
1031
1032 writel(reg, reg_base + CQSPI_REG_READCAPTURE);
1033 }
1034
cqspi_controller_enable(struct cqspi_st * cqspi,bool enable)1035 static void cqspi_controller_enable(struct cqspi_st *cqspi, bool enable)
1036 {
1037 void __iomem *reg_base = cqspi->iobase;
1038 unsigned int reg;
1039
1040 reg = readl(reg_base + CQSPI_REG_CONFIG);
1041
1042 if (enable)
1043 reg |= CQSPI_REG_CONFIG_ENABLE_MASK;
1044 else
1045 reg &= ~CQSPI_REG_CONFIG_ENABLE_MASK;
1046
1047 writel(reg, reg_base + CQSPI_REG_CONFIG);
1048 }
1049
cqspi_configure(struct cqspi_flash_pdata * f_pdata,unsigned long sclk)1050 static void cqspi_configure(struct cqspi_flash_pdata *f_pdata,
1051 unsigned long sclk)
1052 {
1053 struct cqspi_st *cqspi = f_pdata->cqspi;
1054 int switch_cs = (cqspi->current_cs != f_pdata->cs);
1055 int switch_ck = (cqspi->sclk != sclk);
1056
1057 if (switch_cs || switch_ck)
1058 cqspi_controller_enable(cqspi, 0);
1059
1060 /* Switch chip select. */
1061 if (switch_cs) {
1062 cqspi->current_cs = f_pdata->cs;
1063 cqspi_chipselect(f_pdata);
1064 }
1065
1066 /* Setup baudrate divisor and delays */
1067 if (switch_ck) {
1068 cqspi->sclk = sclk;
1069 cqspi_config_baudrate_div(cqspi);
1070 cqspi_delay(f_pdata);
1071 cqspi_readdata_capture(cqspi, !cqspi->rclk_en,
1072 f_pdata->read_delay);
1073 }
1074
1075 if (switch_cs || switch_ck)
1076 cqspi_controller_enable(cqspi, 1);
1077 }
1078
cqspi_write(struct cqspi_flash_pdata * f_pdata,const struct spi_mem_op * op)1079 static ssize_t cqspi_write(struct cqspi_flash_pdata *f_pdata,
1080 const struct spi_mem_op *op)
1081 {
1082 struct cqspi_st *cqspi = f_pdata->cqspi;
1083 loff_t to = op->addr.val;
1084 size_t len = op->data.nbytes;
1085 const u_char *buf = op->data.buf.out;
1086 int ret;
1087
1088 ret = cqspi_set_protocol(f_pdata, op);
1089 if (ret)
1090 return ret;
1091
1092 ret = cqspi_write_setup(f_pdata, op);
1093 if (ret)
1094 return ret;
1095
1096 /*
1097 * Some flashes like the Cypress Semper flash expect a dummy 4-byte
1098 * address (all 0s) with the read status register command in DTR mode.
1099 * But this controller does not support sending dummy address bytes to
1100 * the flash when it is polling the write completion register in DTR
1101 * mode. So, we can not use direct mode when in DTR mode for writing
1102 * data.
1103 */
1104 if (!f_pdata->dtr && cqspi->use_direct_mode &&
1105 ((to + len) <= cqspi->ahb_size)) {
1106 memcpy_toio(cqspi->ahb_base + to, buf, len);
1107 return cqspi_wait_idle(cqspi);
1108 }
1109
1110 return cqspi_indirect_write_execute(f_pdata, to, buf, len);
1111 }
1112
cqspi_rx_dma_callback(void * param)1113 static void cqspi_rx_dma_callback(void *param)
1114 {
1115 struct cqspi_st *cqspi = param;
1116
1117 complete(&cqspi->rx_dma_complete);
1118 }
1119
cqspi_direct_read_execute(struct cqspi_flash_pdata * f_pdata,u_char * buf,loff_t from,size_t len)1120 static int cqspi_direct_read_execute(struct cqspi_flash_pdata *f_pdata,
1121 u_char *buf, loff_t from, size_t len)
1122 {
1123 struct cqspi_st *cqspi = f_pdata->cqspi;
1124 struct device *dev = &cqspi->pdev->dev;
1125 enum dma_ctrl_flags flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
1126 dma_addr_t dma_src = (dma_addr_t)cqspi->mmap_phys_base + from;
1127 int ret = 0;
1128 struct dma_async_tx_descriptor *tx;
1129 dma_cookie_t cookie;
1130 dma_addr_t dma_dst;
1131 struct device *ddev;
1132
1133 if (!cqspi->rx_chan || !virt_addr_valid(buf)) {
1134 memcpy_fromio(buf, cqspi->ahb_base + from, len);
1135 return 0;
1136 }
1137
1138 ddev = cqspi->rx_chan->device->dev;
1139 dma_dst = dma_map_single(ddev, buf, len, DMA_FROM_DEVICE);
1140 if (dma_mapping_error(ddev, dma_dst)) {
1141 dev_err(dev, "dma mapping failed\n");
1142 return -ENOMEM;
1143 }
1144 tx = dmaengine_prep_dma_memcpy(cqspi->rx_chan, dma_dst, dma_src,
1145 len, flags);
1146 if (!tx) {
1147 dev_err(dev, "device_prep_dma_memcpy error\n");
1148 ret = -EIO;
1149 goto err_unmap;
1150 }
1151
1152 tx->callback = cqspi_rx_dma_callback;
1153 tx->callback_param = cqspi;
1154 cookie = tx->tx_submit(tx);
1155 reinit_completion(&cqspi->rx_dma_complete);
1156
1157 ret = dma_submit_error(cookie);
1158 if (ret) {
1159 dev_err(dev, "dma_submit_error %d\n", cookie);
1160 ret = -EIO;
1161 goto err_unmap;
1162 }
1163
1164 dma_async_issue_pending(cqspi->rx_chan);
1165 if (!wait_for_completion_timeout(&cqspi->rx_dma_complete,
1166 msecs_to_jiffies(max_t(size_t, len, 500)))) {
1167 dmaengine_terminate_sync(cqspi->rx_chan);
1168 dev_err(dev, "DMA wait_for_completion_timeout\n");
1169 ret = -ETIMEDOUT;
1170 goto err_unmap;
1171 }
1172
1173 err_unmap:
1174 dma_unmap_single(ddev, dma_dst, len, DMA_FROM_DEVICE);
1175
1176 return ret;
1177 }
1178
cqspi_read(struct cqspi_flash_pdata * f_pdata,const struct spi_mem_op * op)1179 static ssize_t cqspi_read(struct cqspi_flash_pdata *f_pdata,
1180 const struct spi_mem_op *op)
1181 {
1182 struct cqspi_st *cqspi = f_pdata->cqspi;
1183 loff_t from = op->addr.val;
1184 size_t len = op->data.nbytes;
1185 u_char *buf = op->data.buf.in;
1186 int ret;
1187
1188 ret = cqspi_set_protocol(f_pdata, op);
1189 if (ret)
1190 return ret;
1191
1192 ret = cqspi_read_setup(f_pdata, op);
1193 if (ret)
1194 return ret;
1195
1196 if (cqspi->use_direct_mode && ((from + len) <= cqspi->ahb_size))
1197 return cqspi_direct_read_execute(f_pdata, buf, from, len);
1198
1199 return cqspi_indirect_read_execute(f_pdata, buf, from, len);
1200 }
1201
cqspi_mem_process(struct spi_mem * mem,const struct spi_mem_op * op)1202 static int cqspi_mem_process(struct spi_mem *mem, const struct spi_mem_op *op)
1203 {
1204 struct cqspi_st *cqspi = spi_master_get_devdata(mem->spi->master);
1205 struct cqspi_flash_pdata *f_pdata;
1206
1207 f_pdata = &cqspi->f_pdata[mem->spi->chip_select];
1208 cqspi_configure(f_pdata, mem->spi->max_speed_hz);
1209
1210 if (op->data.dir == SPI_MEM_DATA_IN && op->data.buf.in) {
1211 if (!op->addr.nbytes)
1212 return cqspi_command_read(f_pdata, op);
1213
1214 return cqspi_read(f_pdata, op);
1215 }
1216
1217 if (!op->addr.nbytes || !op->data.buf.out)
1218 return cqspi_command_write(f_pdata, op);
1219
1220 return cqspi_write(f_pdata, op);
1221 }
1222
cqspi_exec_mem_op(struct spi_mem * mem,const struct spi_mem_op * op)1223 static int cqspi_exec_mem_op(struct spi_mem *mem, const struct spi_mem_op *op)
1224 {
1225 int ret;
1226
1227 ret = cqspi_mem_process(mem, op);
1228 if (ret)
1229 dev_err(&mem->spi->dev, "operation failed with %d\n", ret);
1230
1231 return ret;
1232 }
1233
cqspi_supports_mem_op(struct spi_mem * mem,const struct spi_mem_op * op)1234 static bool cqspi_supports_mem_op(struct spi_mem *mem,
1235 const struct spi_mem_op *op)
1236 {
1237 bool all_true, all_false;
1238
1239 /*
1240 * op->dummy.dtr is required for converting nbytes into ncycles.
1241 * Also, don't check the dtr field of the op phase having zero nbytes.
1242 */
1243 all_true = op->cmd.dtr &&
1244 (!op->addr.nbytes || op->addr.dtr) &&
1245 (!op->dummy.nbytes || op->dummy.dtr) &&
1246 (!op->data.nbytes || op->data.dtr);
1247
1248 all_false = !op->cmd.dtr && !op->addr.dtr && !op->dummy.dtr &&
1249 !op->data.dtr;
1250
1251 /* Mixed DTR modes not supported. */
1252 if (!(all_true || all_false))
1253 return false;
1254
1255 if (all_true)
1256 return spi_mem_dtr_supports_op(mem, op);
1257 else
1258 return spi_mem_default_supports_op(mem, op);
1259 }
1260
cqspi_of_get_flash_pdata(struct platform_device * pdev,struct cqspi_flash_pdata * f_pdata,struct device_node * np)1261 static int cqspi_of_get_flash_pdata(struct platform_device *pdev,
1262 struct cqspi_flash_pdata *f_pdata,
1263 struct device_node *np)
1264 {
1265 if (of_property_read_u32(np, "cdns,read-delay", &f_pdata->read_delay)) {
1266 dev_err(&pdev->dev, "couldn't determine read-delay\n");
1267 return -ENXIO;
1268 }
1269
1270 if (of_property_read_u32(np, "cdns,tshsl-ns", &f_pdata->tshsl_ns)) {
1271 dev_err(&pdev->dev, "couldn't determine tshsl-ns\n");
1272 return -ENXIO;
1273 }
1274
1275 if (of_property_read_u32(np, "cdns,tsd2d-ns", &f_pdata->tsd2d_ns)) {
1276 dev_err(&pdev->dev, "couldn't determine tsd2d-ns\n");
1277 return -ENXIO;
1278 }
1279
1280 if (of_property_read_u32(np, "cdns,tchsh-ns", &f_pdata->tchsh_ns)) {
1281 dev_err(&pdev->dev, "couldn't determine tchsh-ns\n");
1282 return -ENXIO;
1283 }
1284
1285 if (of_property_read_u32(np, "cdns,tslch-ns", &f_pdata->tslch_ns)) {
1286 dev_err(&pdev->dev, "couldn't determine tslch-ns\n");
1287 return -ENXIO;
1288 }
1289
1290 if (of_property_read_u32(np, "spi-max-frequency", &f_pdata->clk_rate)) {
1291 dev_err(&pdev->dev, "couldn't determine spi-max-frequency\n");
1292 return -ENXIO;
1293 }
1294
1295 return 0;
1296 }
1297
cqspi_of_get_pdata(struct cqspi_st * cqspi)1298 static int cqspi_of_get_pdata(struct cqspi_st *cqspi)
1299 {
1300 struct device *dev = &cqspi->pdev->dev;
1301 struct device_node *np = dev->of_node;
1302
1303 cqspi->is_decoded_cs = of_property_read_bool(np, "cdns,is-decoded-cs");
1304
1305 if (of_property_read_u32(np, "cdns,fifo-depth", &cqspi->fifo_depth)) {
1306 dev_err(dev, "couldn't determine fifo-depth\n");
1307 return -ENXIO;
1308 }
1309
1310 if (of_property_read_u32(np, "cdns,fifo-width", &cqspi->fifo_width)) {
1311 dev_err(dev, "couldn't determine fifo-width\n");
1312 return -ENXIO;
1313 }
1314
1315 if (of_property_read_u32(np, "cdns,trigger-address",
1316 &cqspi->trigger_address)) {
1317 dev_err(dev, "couldn't determine trigger-address\n");
1318 return -ENXIO;
1319 }
1320
1321 if (of_property_read_u32(np, "num-cs", &cqspi->num_chipselect))
1322 cqspi->num_chipselect = CQSPI_MAX_CHIPSELECT;
1323
1324 cqspi->rclk_en = of_property_read_bool(np, "cdns,rclk-en");
1325
1326 return 0;
1327 }
1328
cqspi_controller_init(struct cqspi_st * cqspi)1329 static void cqspi_controller_init(struct cqspi_st *cqspi)
1330 {
1331 u32 reg;
1332
1333 cqspi_controller_enable(cqspi, 0);
1334
1335 /* Configure the remap address register, no remap */
1336 writel(0, cqspi->iobase + CQSPI_REG_REMAP);
1337
1338 /* Disable all interrupts. */
1339 writel(0, cqspi->iobase + CQSPI_REG_IRQMASK);
1340
1341 /* Configure the SRAM split to 1:1 . */
1342 writel(cqspi->fifo_depth / 2, cqspi->iobase + CQSPI_REG_SRAMPARTITION);
1343
1344 /* Load indirect trigger address. */
1345 writel(cqspi->trigger_address,
1346 cqspi->iobase + CQSPI_REG_INDIRECTTRIGGER);
1347
1348 /* Program read watermark -- 1/2 of the FIFO. */
1349 writel(cqspi->fifo_depth * cqspi->fifo_width / 2,
1350 cqspi->iobase + CQSPI_REG_INDIRECTRDWATERMARK);
1351 /* Program write watermark -- 1/8 of the FIFO. */
1352 writel(cqspi->fifo_depth * cqspi->fifo_width / 8,
1353 cqspi->iobase + CQSPI_REG_INDIRECTWRWATERMARK);
1354
1355 /* Disable direct access controller */
1356 if (!cqspi->use_direct_mode) {
1357 reg = readl(cqspi->iobase + CQSPI_REG_CONFIG);
1358 reg &= ~CQSPI_REG_CONFIG_ENB_DIR_ACC_CTRL;
1359 writel(reg, cqspi->iobase + CQSPI_REG_CONFIG);
1360 }
1361
1362 cqspi_controller_enable(cqspi, 1);
1363 }
1364
cqspi_request_mmap_dma(struct cqspi_st * cqspi)1365 static int cqspi_request_mmap_dma(struct cqspi_st *cqspi)
1366 {
1367 dma_cap_mask_t mask;
1368
1369 dma_cap_zero(mask);
1370 dma_cap_set(DMA_MEMCPY, mask);
1371
1372 cqspi->rx_chan = dma_request_chan_by_mask(&mask);
1373 if (IS_ERR(cqspi->rx_chan)) {
1374 int ret = PTR_ERR(cqspi->rx_chan);
1375 cqspi->rx_chan = NULL;
1376 return dev_err_probe(&cqspi->pdev->dev, ret, "No Rx DMA available\n");
1377 }
1378 init_completion(&cqspi->rx_dma_complete);
1379
1380 return 0;
1381 }
1382
cqspi_get_name(struct spi_mem * mem)1383 static const char *cqspi_get_name(struct spi_mem *mem)
1384 {
1385 struct cqspi_st *cqspi = spi_master_get_devdata(mem->spi->master);
1386 struct device *dev = &cqspi->pdev->dev;
1387
1388 return devm_kasprintf(dev, GFP_KERNEL, "%s.%d", dev_name(dev), mem->spi->chip_select);
1389 }
1390
1391 static const struct spi_controller_mem_ops cqspi_mem_ops = {
1392 .exec_op = cqspi_exec_mem_op,
1393 .get_name = cqspi_get_name,
1394 .supports_op = cqspi_supports_mem_op,
1395 };
1396
cqspi_setup_flash(struct cqspi_st * cqspi)1397 static int cqspi_setup_flash(struct cqspi_st *cqspi)
1398 {
1399 struct platform_device *pdev = cqspi->pdev;
1400 struct device *dev = &pdev->dev;
1401 struct device_node *np = dev->of_node;
1402 struct cqspi_flash_pdata *f_pdata;
1403 unsigned int cs;
1404 int ret;
1405
1406 /* Get flash device data */
1407 for_each_available_child_of_node(dev->of_node, np) {
1408 ret = of_property_read_u32(np, "reg", &cs);
1409 if (ret) {
1410 dev_err(dev, "Couldn't determine chip select.\n");
1411 of_node_put(np);
1412 return ret;
1413 }
1414
1415 if (cs >= CQSPI_MAX_CHIPSELECT) {
1416 dev_err(dev, "Chip select %d out of range.\n", cs);
1417 of_node_put(np);
1418 return -EINVAL;
1419 }
1420
1421 f_pdata = &cqspi->f_pdata[cs];
1422 f_pdata->cqspi = cqspi;
1423 f_pdata->cs = cs;
1424
1425 ret = cqspi_of_get_flash_pdata(pdev, f_pdata, np);
1426 if (ret) {
1427 of_node_put(np);
1428 return ret;
1429 }
1430 }
1431
1432 return 0;
1433 }
1434
cqspi_probe(struct platform_device * pdev)1435 static int cqspi_probe(struct platform_device *pdev)
1436 {
1437 const struct cqspi_driver_platdata *ddata;
1438 struct reset_control *rstc, *rstc_ocp;
1439 struct device *dev = &pdev->dev;
1440 struct spi_master *master;
1441 struct resource *res_ahb;
1442 struct cqspi_st *cqspi;
1443 struct resource *res;
1444 int ret;
1445 int irq;
1446
1447 master = spi_alloc_master(&pdev->dev, sizeof(*cqspi));
1448 if (!master) {
1449 dev_err(&pdev->dev, "spi_alloc_master failed\n");
1450 return -ENOMEM;
1451 }
1452 master->mode_bits = SPI_RX_QUAD | SPI_RX_DUAL;
1453 master->mem_ops = &cqspi_mem_ops;
1454 master->dev.of_node = pdev->dev.of_node;
1455
1456 cqspi = spi_master_get_devdata(master);
1457
1458 cqspi->pdev = pdev;
1459 platform_set_drvdata(pdev, cqspi);
1460
1461 /* Obtain configuration from OF. */
1462 ret = cqspi_of_get_pdata(cqspi);
1463 if (ret) {
1464 dev_err(dev, "Cannot get mandatory OF data.\n");
1465 ret = -ENODEV;
1466 goto probe_master_put;
1467 }
1468
1469 /* Obtain QSPI clock. */
1470 cqspi->clk = devm_clk_get(dev, NULL);
1471 if (IS_ERR(cqspi->clk)) {
1472 dev_err(dev, "Cannot claim QSPI clock.\n");
1473 ret = PTR_ERR(cqspi->clk);
1474 goto probe_master_put;
1475 }
1476
1477 /* Obtain and remap controller address. */
1478 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1479 cqspi->iobase = devm_ioremap_resource(dev, res);
1480 if (IS_ERR(cqspi->iobase)) {
1481 dev_err(dev, "Cannot remap controller address.\n");
1482 ret = PTR_ERR(cqspi->iobase);
1483 goto probe_master_put;
1484 }
1485
1486 /* Obtain and remap AHB address. */
1487 res_ahb = platform_get_resource(pdev, IORESOURCE_MEM, 1);
1488 cqspi->ahb_base = devm_ioremap_resource(dev, res_ahb);
1489 if (IS_ERR(cqspi->ahb_base)) {
1490 dev_err(dev, "Cannot remap AHB address.\n");
1491 ret = PTR_ERR(cqspi->ahb_base);
1492 goto probe_master_put;
1493 }
1494 cqspi->mmap_phys_base = (dma_addr_t)res_ahb->start;
1495 cqspi->ahb_size = resource_size(res_ahb);
1496
1497 init_completion(&cqspi->transfer_complete);
1498
1499 /* Obtain IRQ line. */
1500 irq = platform_get_irq(pdev, 0);
1501 if (irq < 0) {
1502 ret = -ENXIO;
1503 goto probe_master_put;
1504 }
1505
1506 pm_runtime_enable(dev);
1507 ret = pm_runtime_get_sync(dev);
1508 if (ret < 0) {
1509 pm_runtime_put_noidle(dev);
1510 goto probe_master_put;
1511 }
1512
1513 ret = clk_prepare_enable(cqspi->clk);
1514 if (ret) {
1515 dev_err(dev, "Cannot enable QSPI clock.\n");
1516 goto probe_clk_failed;
1517 }
1518
1519 /* Obtain QSPI reset control */
1520 rstc = devm_reset_control_get_optional_exclusive(dev, "qspi");
1521 if (IS_ERR(rstc)) {
1522 ret = PTR_ERR(rstc);
1523 dev_err(dev, "Cannot get QSPI reset.\n");
1524 goto probe_reset_failed;
1525 }
1526
1527 rstc_ocp = devm_reset_control_get_optional_exclusive(dev, "qspi-ocp");
1528 if (IS_ERR(rstc_ocp)) {
1529 ret = PTR_ERR(rstc_ocp);
1530 dev_err(dev, "Cannot get QSPI OCP reset.\n");
1531 goto probe_reset_failed;
1532 }
1533
1534 reset_control_assert(rstc);
1535 reset_control_deassert(rstc);
1536
1537 reset_control_assert(rstc_ocp);
1538 reset_control_deassert(rstc_ocp);
1539
1540 cqspi->master_ref_clk_hz = clk_get_rate(cqspi->clk);
1541 master->max_speed_hz = cqspi->master_ref_clk_hz;
1542 ddata = of_device_get_match_data(dev);
1543 if (ddata) {
1544 if (ddata->quirks & CQSPI_NEEDS_WR_DELAY)
1545 cqspi->wr_delay = 50 * DIV_ROUND_UP(NSEC_PER_SEC,
1546 cqspi->master_ref_clk_hz);
1547 if (ddata->hwcaps_mask & CQSPI_SUPPORTS_OCTAL)
1548 master->mode_bits |= SPI_RX_OCTAL | SPI_TX_OCTAL;
1549 if (!(ddata->quirks & CQSPI_DISABLE_DAC_MODE))
1550 cqspi->use_direct_mode = true;
1551 }
1552
1553 ret = devm_request_irq(dev, irq, cqspi_irq_handler, 0,
1554 pdev->name, cqspi);
1555 if (ret) {
1556 dev_err(dev, "Cannot request IRQ.\n");
1557 goto probe_reset_failed;
1558 }
1559
1560 cqspi_wait_idle(cqspi);
1561 cqspi_controller_init(cqspi);
1562 cqspi->current_cs = -1;
1563 cqspi->sclk = 0;
1564
1565 master->num_chipselect = cqspi->num_chipselect;
1566
1567 ret = cqspi_setup_flash(cqspi);
1568 if (ret) {
1569 dev_err(dev, "failed to setup flash parameters %d\n", ret);
1570 goto probe_setup_failed;
1571 }
1572
1573 if (cqspi->use_direct_mode) {
1574 ret = cqspi_request_mmap_dma(cqspi);
1575 if (ret == -EPROBE_DEFER)
1576 goto probe_setup_failed;
1577 }
1578
1579 ret = devm_spi_register_master(dev, master);
1580 if (ret) {
1581 dev_err(&pdev->dev, "failed to register SPI ctlr %d\n", ret);
1582 goto probe_setup_failed;
1583 }
1584
1585 return 0;
1586 probe_setup_failed:
1587 cqspi_controller_enable(cqspi, 0);
1588 probe_reset_failed:
1589 clk_disable_unprepare(cqspi->clk);
1590 probe_clk_failed:
1591 pm_runtime_put_sync(dev);
1592 pm_runtime_disable(dev);
1593 probe_master_put:
1594 spi_master_put(master);
1595 return ret;
1596 }
1597
cqspi_remove(struct platform_device * pdev)1598 static int cqspi_remove(struct platform_device *pdev)
1599 {
1600 struct cqspi_st *cqspi = platform_get_drvdata(pdev);
1601
1602 cqspi_controller_enable(cqspi, 0);
1603
1604 if (cqspi->rx_chan)
1605 dma_release_channel(cqspi->rx_chan);
1606
1607 clk_disable_unprepare(cqspi->clk);
1608
1609 pm_runtime_put_sync(&pdev->dev);
1610 pm_runtime_disable(&pdev->dev);
1611
1612 return 0;
1613 }
1614
1615 #ifdef CONFIG_PM_SLEEP
cqspi_suspend(struct device * dev)1616 static int cqspi_suspend(struct device *dev)
1617 {
1618 struct cqspi_st *cqspi = dev_get_drvdata(dev);
1619
1620 cqspi_controller_enable(cqspi, 0);
1621 return 0;
1622 }
1623
cqspi_resume(struct device * dev)1624 static int cqspi_resume(struct device *dev)
1625 {
1626 struct cqspi_st *cqspi = dev_get_drvdata(dev);
1627
1628 cqspi_controller_enable(cqspi, 1);
1629 return 0;
1630 }
1631
1632 static const struct dev_pm_ops cqspi__dev_pm_ops = {
1633 .suspend = cqspi_suspend,
1634 .resume = cqspi_resume,
1635 };
1636
1637 #define CQSPI_DEV_PM_OPS (&cqspi__dev_pm_ops)
1638 #else
1639 #define CQSPI_DEV_PM_OPS NULL
1640 #endif
1641
1642 static const struct cqspi_driver_platdata cdns_qspi = {
1643 .quirks = CQSPI_DISABLE_DAC_MODE,
1644 };
1645
1646 static const struct cqspi_driver_platdata k2g_qspi = {
1647 .quirks = CQSPI_NEEDS_WR_DELAY,
1648 };
1649
1650 static const struct cqspi_driver_platdata am654_ospi = {
1651 .hwcaps_mask = CQSPI_SUPPORTS_OCTAL,
1652 .quirks = CQSPI_NEEDS_WR_DELAY,
1653 };
1654
1655 static const struct cqspi_driver_platdata intel_lgm_qspi = {
1656 .quirks = CQSPI_DISABLE_DAC_MODE,
1657 };
1658
1659 static const struct of_device_id cqspi_dt_ids[] = {
1660 {
1661 .compatible = "cdns,qspi-nor",
1662 .data = &cdns_qspi,
1663 },
1664 {
1665 .compatible = "ti,k2g-qspi",
1666 .data = &k2g_qspi,
1667 },
1668 {
1669 .compatible = "ti,am654-ospi",
1670 .data = &am654_ospi,
1671 },
1672 {
1673 .compatible = "intel,lgm-qspi",
1674 .data = &intel_lgm_qspi,
1675 },
1676 { /* end of table */ }
1677 };
1678
1679 MODULE_DEVICE_TABLE(of, cqspi_dt_ids);
1680
1681 static struct platform_driver cqspi_platform_driver = {
1682 .probe = cqspi_probe,
1683 .remove = cqspi_remove,
1684 .driver = {
1685 .name = CQSPI_NAME,
1686 .pm = CQSPI_DEV_PM_OPS,
1687 .of_match_table = cqspi_dt_ids,
1688 },
1689 };
1690
1691 module_platform_driver(cqspi_platform_driver);
1692
1693 MODULE_DESCRIPTION("Cadence QSPI Controller Driver");
1694 MODULE_LICENSE("GPL v2");
1695 MODULE_ALIAS("platform:" CQSPI_NAME);
1696 MODULE_AUTHOR("Ley Foon Tan <lftan@altera.com>");
1697 MODULE_AUTHOR("Graham Moore <grmoore@opensource.altera.com>");
1698 MODULE_AUTHOR("Vadivel Murugan R <vadivel.muruganx.ramuthevar@intel.com>");
1699 MODULE_AUTHOR("Vignesh Raghavendra <vigneshr@ti.com>");
1700 MODULE_AUTHOR("Pratyush Yadav <p.yadav@ti.com>");
1701
