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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Marvell Orion SPI controller driver
4 *
5 * Author: Shadi Ammouri <shadi@marvell.com>
6 * Copyright (C) 2007-2008 Marvell Ltd.
7 */
8
9#include <linux/interrupt.h>
10#include <linux/delay.h>
11#include <linux/platform_device.h>
12#include <linux/err.h>
13#include <linux/io.h>
14#include <linux/spi/spi.h>
15#include <linux/module.h>
16#include <linux/pm_runtime.h>
17#include <linux/of.h>
18#include <linux/of_address.h>
19#include <linux/of_device.h>
20#include <linux/clk.h>
21#include <linux/sizes.h>
22#include <asm/unaligned.h>
23
24#define DRIVER_NAME "orion_spi"
25
26/* Runtime PM autosuspend timeout: PM is fairly light on this driver */
27#define SPI_AUTOSUSPEND_TIMEOUT 200
28
29/* Some SoCs using this driver support up to 8 chip selects.
30 * It is up to the implementer to only use the chip selects
31 * that are available.
32 */
33#define ORION_NUM_CHIPSELECTS 8
34
35#define ORION_SPI_WAIT_RDY_MAX_LOOP 2000 /* in usec */
36
37#define ORION_SPI_IF_CTRL_REG 0x00
38#define ORION_SPI_IF_CONFIG_REG 0x04
39#define ORION_SPI_IF_RXLSBF BIT(14)
40#define ORION_SPI_IF_TXLSBF BIT(13)
41#define ORION_SPI_DATA_OUT_REG 0x08
42#define ORION_SPI_DATA_IN_REG 0x0c
43#define ORION_SPI_INT_CAUSE_REG 0x10
44#define ORION_SPI_TIMING_PARAMS_REG 0x18
45
46/* Register for the "Direct Mode" */
47#define SPI_DIRECT_WRITE_CONFIG_REG 0x20
48
49#define ORION_SPI_TMISO_SAMPLE_MASK (0x3 << 6)
50#define ORION_SPI_TMISO_SAMPLE_1 (1 << 6)
51#define ORION_SPI_TMISO_SAMPLE_2 (2 << 6)
52
53#define ORION_SPI_MODE_CPOL (1 << 11)
54#define ORION_SPI_MODE_CPHA (1 << 12)
55#define ORION_SPI_IF_8_16_BIT_MODE (1 << 5)
56#define ORION_SPI_CLK_PRESCALE_MASK 0x1F
57#define ARMADA_SPI_CLK_PRESCALE_MASK 0xDF
58#define ORION_SPI_MODE_MASK (ORION_SPI_MODE_CPOL | \
59 ORION_SPI_MODE_CPHA)
60#define ORION_SPI_CS_MASK 0x1C
61#define ORION_SPI_CS_SHIFT 2
62#define ORION_SPI_CS(cs) ((cs << ORION_SPI_CS_SHIFT) & \
63 ORION_SPI_CS_MASK)
64
65enum orion_spi_type {
66 ORION_SPI,
67 ARMADA_SPI,
68};
69
70struct orion_spi_dev {
71 enum orion_spi_type typ;
72 /*
73 * min_divisor and max_hz should be exclusive, the only we can
74 * have both is for managing the armada-370-spi case with old
75 * device tree
76 */
77 unsigned long max_hz;
78 unsigned int min_divisor;
79 unsigned int max_divisor;
80 u32 prescale_mask;
81 bool is_errata_50mhz_ac;
82};
83
84struct orion_direct_acc {
85 void __iomem *vaddr;
86 u32 size;
87};
88
89struct orion_child_options {
90 struct orion_direct_acc direct_access;
91};
92
93struct orion_spi {
94 struct spi_master *master;
95 void __iomem *base;
96 struct clk *clk;
97 struct clk *axi_clk;
98 const struct orion_spi_dev *devdata;
99 struct device *dev;
100
101 struct orion_child_options child[ORION_NUM_CHIPSELECTS];
102};
103
104#ifdef CONFIG_PM
105static int orion_spi_runtime_suspend(struct device *dev);
106static int orion_spi_runtime_resume(struct device *dev);
107#endif
108
109static inline void __iomem *spi_reg(struct orion_spi *orion_spi, u32 reg)
110{
111 return orion_spi->base + reg;
112}
113
114static inline void
115orion_spi_setbits(struct orion_spi *orion_spi, u32 reg, u32 mask)
116{
117 void __iomem *reg_addr = spi_reg(orion_spi, reg);
118 u32 val;
119
120 val = readl(reg_addr);
121 val |= mask;
122 writel(val, reg_addr);
123}
124
125static inline void
126orion_spi_clrbits(struct orion_spi *orion_spi, u32 reg, u32 mask)
127{
128 void __iomem *reg_addr = spi_reg(orion_spi, reg);
129 u32 val;
130
131 val = readl(reg_addr);
132 val &= ~mask;
133 writel(val, reg_addr);
134}
135
136static int orion_spi_baudrate_set(struct spi_device *spi, unsigned int speed)
137{
138 u32 tclk_hz;
139 u32 rate;
140 u32 prescale;
141 u32 reg;
142 struct orion_spi *orion_spi;
143 const struct orion_spi_dev *devdata;
144
145 orion_spi = spi_master_get_devdata(spi->master);
146 devdata = orion_spi->devdata;
147
148 tclk_hz = clk_get_rate(orion_spi->clk);
149
150 if (devdata->typ == ARMADA_SPI) {
151 /*
152 * Given the core_clk (tclk_hz) and the target rate (speed) we
153 * determine the best values for SPR (in [0 .. 15]) and SPPR (in
154 * [0..7]) such that
155 *
156 * core_clk / (SPR * 2 ** SPPR)
157 *
158 * is as big as possible but not bigger than speed.
159 */
160
161 /* best integer divider: */
162 unsigned divider = DIV_ROUND_UP(tclk_hz, speed);
163 unsigned spr, sppr;
164
165 if (divider < 16) {
166 /* This is the easy case, divider is less than 16 */
167 spr = divider;
168 sppr = 0;
169
170 } else {
171 unsigned two_pow_sppr;
172 /*
173 * Find the highest bit set in divider. This and the
174 * three next bits define SPR (apart from rounding).
175 * SPPR is then the number of zero bits that must be
176 * appended:
177 */
178 sppr = fls(divider) - 4;
179
180 /*
181 * As SPR only has 4 bits, we have to round divider up
182 * to the next multiple of 2 ** sppr.
183 */
184 two_pow_sppr = 1 << sppr;
185 divider = (divider + two_pow_sppr - 1) & -two_pow_sppr;
186
187 /*
188 * recalculate sppr as rounding up divider might have
189 * increased it enough to change the position of the
190 * highest set bit. In this case the bit that now
191 * doesn't make it into SPR is 0, so there is no need to
192 * round again.
193 */
194 sppr = fls(divider) - 4;
195 spr = divider >> sppr;
196
197 /*
198 * Now do range checking. SPR is constructed to have a
199 * width of 4 bits, so this is fine for sure. So we
200 * still need to check for sppr to fit into 3 bits:
201 */
202 if (sppr > 7)
203 return -EINVAL;
204 }
205
206 prescale = ((sppr & 0x6) << 5) | ((sppr & 0x1) << 4) | spr;
207 } else {
208 /*
209 * the supported rates are: 4,6,8...30
210 * round up as we look for equal or less speed
211 */
212 rate = DIV_ROUND_UP(tclk_hz, speed);
213 rate = roundup(rate, 2);
214
215 /* check if requested speed is too small */
216 if (rate > 30)
217 return -EINVAL;
218
219 if (rate < 4)
220 rate = 4;
221
222 /* Convert the rate to SPI clock divisor value. */
223 prescale = 0x10 + rate/2;
224 }
225
226 reg = readl(spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG));
227 reg = ((reg & ~devdata->prescale_mask) | prescale);
228 writel(reg, spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG));
229
230 return 0;
231}
232
233static void
234orion_spi_mode_set(struct spi_device *spi)
235{
236 u32 reg;
237 struct orion_spi *orion_spi;
238
239 orion_spi = spi_master_get_devdata(spi->master);
240
241 reg = readl(spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG));
242 reg &= ~ORION_SPI_MODE_MASK;
243 if (spi->mode & SPI_CPOL)
244 reg |= ORION_SPI_MODE_CPOL;
245 if (spi->mode & SPI_CPHA)
246 reg |= ORION_SPI_MODE_CPHA;
247 if (spi->mode & SPI_LSB_FIRST)
248 reg |= ORION_SPI_IF_RXLSBF | ORION_SPI_IF_TXLSBF;
249 else
250 reg &= ~(ORION_SPI_IF_RXLSBF | ORION_SPI_IF_TXLSBF);
251
252 writel(reg, spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG));
253}
254
255static void
256orion_spi_50mhz_ac_timing_erratum(struct spi_device *spi, unsigned int speed)
257{
258 u32 reg;
259 struct orion_spi *orion_spi;
260
261 orion_spi = spi_master_get_devdata(spi->master);
262
263 /*
264 * Erratum description: (Erratum NO. FE-9144572) The device
265 * SPI interface supports frequencies of up to 50 MHz.
266 * However, due to this erratum, when the device core clock is
267 * 250 MHz and the SPI interfaces is configured for 50MHz SPI
268 * clock and CPOL=CPHA=1 there might occur data corruption on
269 * reads from the SPI device.
270 * Erratum Workaround:
271 * Work in one of the following configurations:
272 * 1. Set CPOL=CPHA=0 in "SPI Interface Configuration
273 * Register".
274 * 2. Set TMISO_SAMPLE value to 0x2 in "SPI Timing Parameters 1
275 * Register" before setting the interface.
276 */
277 reg = readl(spi_reg(orion_spi, ORION_SPI_TIMING_PARAMS_REG));
278 reg &= ~ORION_SPI_TMISO_SAMPLE_MASK;
279
280 if (clk_get_rate(orion_spi->clk) == 250000000 &&
281 speed == 50000000 && spi->mode & SPI_CPOL &&
282 spi->mode & SPI_CPHA)
283 reg |= ORION_SPI_TMISO_SAMPLE_2;
284 else
285 reg |= ORION_SPI_TMISO_SAMPLE_1; /* This is the default value */
286
287 writel(reg, spi_reg(orion_spi, ORION_SPI_TIMING_PARAMS_REG));
288}
289
290/*
291 * called only when no transfer is active on the bus
292 */
293static int
294orion_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
295{
296 struct orion_spi *orion_spi;
297 unsigned int speed = spi->max_speed_hz;
298 unsigned int bits_per_word = spi->bits_per_word;
299 int rc;
300
301 orion_spi = spi_master_get_devdata(spi->master);
302
303 if ((t != NULL) && t->speed_hz)
304 speed = t->speed_hz;
305
306 if ((t != NULL) && t->bits_per_word)
307 bits_per_word = t->bits_per_word;
308
309 orion_spi_mode_set(spi);
310
311 if (orion_spi->devdata->is_errata_50mhz_ac)
312 orion_spi_50mhz_ac_timing_erratum(spi, speed);
313
314 rc = orion_spi_baudrate_set(spi, speed);
315 if (rc)
316 return rc;
317
318 if (bits_per_word == 16)
319 orion_spi_setbits(orion_spi, ORION_SPI_IF_CONFIG_REG,
320 ORION_SPI_IF_8_16_BIT_MODE);
321 else
322 orion_spi_clrbits(orion_spi, ORION_SPI_IF_CONFIG_REG,
323 ORION_SPI_IF_8_16_BIT_MODE);
324
325 return 0;
326}
327
328static void orion_spi_set_cs(struct spi_device *spi, bool enable)
329{
330 struct orion_spi *orion_spi;
331 void __iomem *ctrl_reg;
332 u32 val;
333
334 orion_spi = spi_master_get_devdata(spi->master);
335 ctrl_reg = spi_reg(orion_spi, ORION_SPI_IF_CTRL_REG);
336
337 val = readl(ctrl_reg);
338
339 /* Clear existing chip-select and assertion state */
340 val &= ~(ORION_SPI_CS_MASK | 0x1);
341
342 /*
343 * If this line is using a GPIO to control chip select, this internal
344 * .set_cs() function will still be called, so we clear any previous
345 * chip select. The CS we activate will not have any elecrical effect,
346 * as it is handled by a GPIO, but that doesn't matter. What we need
347 * is to deassert the old chip select and assert some other chip select.
348 */
349 val |= ORION_SPI_CS(spi->chip_select);
350
351 /*
352 * Chip select logic is inverted from spi_set_cs(). For lines using a
353 * GPIO to do chip select SPI_CS_HIGH is enforced and inversion happens
354 * in the GPIO library, but we don't care about that, because in those
355 * cases we are dealing with an unused native CS anyways so the polarity
356 * doesn't matter.
357 */
358 if (!enable)
359 val |= 0x1;
360
361 /*
362 * To avoid toggling unwanted chip selects update the register
363 * with a single write.
364 */
365 writel(val, ctrl_reg);
366}
367
368static inline int orion_spi_wait_till_ready(struct orion_spi *orion_spi)
369{
370 int i;
371
372 for (i = 0; i < ORION_SPI_WAIT_RDY_MAX_LOOP; i++) {
373 if (readl(spi_reg(orion_spi, ORION_SPI_INT_CAUSE_REG)))
374 return 1;
375
376 udelay(1);
377 }
378
379 return -1;
380}
381
382static inline int
383orion_spi_write_read_8bit(struct spi_device *spi,
384 const u8 **tx_buf, u8 **rx_buf)
385{
386 void __iomem *tx_reg, *rx_reg, *int_reg;
387 struct orion_spi *orion_spi;
388 bool cs_single_byte;
389
390 cs_single_byte = spi->mode & SPI_CS_WORD;
391
392 orion_spi = spi_master_get_devdata(spi->master);
393
394 if (cs_single_byte)
395 orion_spi_set_cs(spi, 0);
396
397 tx_reg = spi_reg(orion_spi, ORION_SPI_DATA_OUT_REG);
398 rx_reg = spi_reg(orion_spi, ORION_SPI_DATA_IN_REG);
399 int_reg = spi_reg(orion_spi, ORION_SPI_INT_CAUSE_REG);
400
401 /* clear the interrupt cause register */
402 writel(0x0, int_reg);
403
404 if (tx_buf && *tx_buf)
405 writel(*(*tx_buf)++, tx_reg);
406 else
407 writel(0, tx_reg);
408
409 if (orion_spi_wait_till_ready(orion_spi) < 0) {
410 if (cs_single_byte) {
411 orion_spi_set_cs(spi, 1);
412 /* Satisfy some SLIC devices requirements */
413 udelay(4);
414 }
415 dev_err(&spi->dev, "TXS timed out\n");
416 return -1;
417 }
418
419 if (rx_buf && *rx_buf)
420 *(*rx_buf)++ = readl(rx_reg);
421
422 if (cs_single_byte) {
423 orion_spi_set_cs(spi, 1);
424 /* Satisfy some SLIC devices requirements */
425 udelay(4);
426 }
427
428 return 1;
429}
430
431static inline int
432orion_spi_write_read_16bit(struct spi_device *spi,
433 const u16 **tx_buf, u16 **rx_buf)
434{
435 void __iomem *tx_reg, *rx_reg, *int_reg;
436 struct orion_spi *orion_spi;
437
438 if (spi->mode & SPI_CS_WORD) {
439 dev_err(&spi->dev, "SPI_CS_WORD is only supported for 8 bit words\n");
440 return -1;
441 }
442
443 orion_spi = spi_master_get_devdata(spi->master);
444 tx_reg = spi_reg(orion_spi, ORION_SPI_DATA_OUT_REG);
445 rx_reg = spi_reg(orion_spi, ORION_SPI_DATA_IN_REG);
446 int_reg = spi_reg(orion_spi, ORION_SPI_INT_CAUSE_REG);
447
448 /* clear the interrupt cause register */
449 writel(0x0, int_reg);
450
451 if (tx_buf && *tx_buf)
452 writel(__cpu_to_le16(get_unaligned((*tx_buf)++)), tx_reg);
453 else
454 writel(0, tx_reg);
455
456 if (orion_spi_wait_till_ready(orion_spi) < 0) {
457 dev_err(&spi->dev, "TXS timed out\n");
458 return -1;
459 }
460
461 if (rx_buf && *rx_buf)
462 put_unaligned(__le16_to_cpu(readl(rx_reg)), (*rx_buf)++);
463
464 return 1;
465}
466
467static unsigned int
468orion_spi_write_read(struct spi_device *spi, struct spi_transfer *xfer)
469{
470 unsigned int count;
471 int word_len;
472 struct orion_spi *orion_spi;
473 int cs = spi->chip_select;
474 void __iomem *vaddr;
475
476 word_len = spi->bits_per_word;
477 count = xfer->len;
478
479 orion_spi = spi_master_get_devdata(spi->master);
480
481 /*
482 * Use SPI direct write mode if base address is available
483 * and SPI_CS_WORD flag is not set.
484 * Otherwise fall back to PIO mode for this transfer.
485 */
486 vaddr = orion_spi->child[cs].direct_access.vaddr;
487
488 if (vaddr && xfer->tx_buf && word_len == 8 && (spi->mode & SPI_CS_WORD) == 0) {
489 unsigned int cnt = count / 4;
490 unsigned int rem = count % 4;
491
492 /*
493 * Send the TX-data to the SPI device via the direct
494 * mapped address window
495 */
496 iowrite32_rep(vaddr, xfer->tx_buf, cnt);
497 if (rem) {
498 u32 *buf = (u32 *)xfer->tx_buf;
499
500 iowrite8_rep(vaddr, &buf[cnt], rem);
501 }
502
503 return count;
504 }
505
506 if (word_len == 8) {
507 const u8 *tx = xfer->tx_buf;
508 u8 *rx = xfer->rx_buf;
509
510 do {
511 if (orion_spi_write_read_8bit(spi, &tx, &rx) < 0)
512 goto out;
513 count--;
514 spi_delay_exec(&xfer->word_delay, xfer);
515 } while (count);
516 } else if (word_len == 16) {
517 const u16 *tx = xfer->tx_buf;
518 u16 *rx = xfer->rx_buf;
519
520 do {
521 if (orion_spi_write_read_16bit(spi, &tx, &rx) < 0)
522 goto out;
523 count -= 2;
524 spi_delay_exec(&xfer->word_delay, xfer);
525 } while (count);
526 }
527
528out:
529 return xfer->len - count;
530}
531
532static int orion_spi_transfer_one(struct spi_master *master,
533 struct spi_device *spi,
534 struct spi_transfer *t)
535{
536 int status = 0;
537
538 status = orion_spi_setup_transfer(spi, t);
539 if (status < 0)
540 return status;
541
542 if (t->len)
543 orion_spi_write_read(spi, t);
544
545 return status;
546}
547
548static int orion_spi_setup(struct spi_device *spi)
549{
550 int ret;
551#ifdef CONFIG_PM
552 struct orion_spi *orion_spi = spi_master_get_devdata(spi->master);
553 struct device *dev = orion_spi->dev;
554
555 orion_spi_runtime_resume(dev);
556#endif
557
558 ret = orion_spi_setup_transfer(spi, NULL);
559
560#ifdef CONFIG_PM
561 orion_spi_runtime_suspend(dev);
562#endif
563
564 return ret;
565}
566
567static int orion_spi_reset(struct orion_spi *orion_spi)
568{
569 /* Verify that the CS is deasserted */
570 orion_spi_clrbits(orion_spi, ORION_SPI_IF_CTRL_REG, 0x1);
571
572 /* Don't deassert CS between the direct mapped SPI transfers */
573 writel(0, spi_reg(orion_spi, SPI_DIRECT_WRITE_CONFIG_REG));
574
575 return 0;
576}
577
578static const struct orion_spi_dev orion_spi_dev_data = {
579 .typ = ORION_SPI,
580 .min_divisor = 4,
581 .max_divisor = 30,
582 .prescale_mask = ORION_SPI_CLK_PRESCALE_MASK,
583};
584
585static const struct orion_spi_dev armada_370_spi_dev_data = {
586 .typ = ARMADA_SPI,
587 .min_divisor = 4,
588 .max_divisor = 1920,
589 .max_hz = 50000000,
590 .prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK,
591};
592
593static const struct orion_spi_dev armada_xp_spi_dev_data = {
594 .typ = ARMADA_SPI,
595 .max_hz = 50000000,
596 .max_divisor = 1920,
597 .prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK,
598};
599
600static const struct orion_spi_dev armada_375_spi_dev_data = {
601 .typ = ARMADA_SPI,
602 .min_divisor = 15,
603 .max_divisor = 1920,
604 .prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK,
605};
606
607static const struct orion_spi_dev armada_380_spi_dev_data = {
608 .typ = ARMADA_SPI,
609 .max_hz = 50000000,
610 .max_divisor = 1920,
611 .prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK,
612 .is_errata_50mhz_ac = true,
613};
614
615static const struct of_device_id orion_spi_of_match_table[] = {
616 {
617 .compatible = "marvell,orion-spi",
618 .data = &orion_spi_dev_data,
619 },
620 {
621 .compatible = "marvell,armada-370-spi",
622 .data = &armada_370_spi_dev_data,
623 },
624 {
625 .compatible = "marvell,armada-375-spi",
626 .data = &armada_375_spi_dev_data,
627 },
628 {
629 .compatible = "marvell,armada-380-spi",
630 .data = &armada_380_spi_dev_data,
631 },
632 {
633 .compatible = "marvell,armada-390-spi",
634 .data = &armada_xp_spi_dev_data,
635 },
636 {
637 .compatible = "marvell,armada-xp-spi",
638 .data = &armada_xp_spi_dev_data,
639 },
640
641 {}
642};
643MODULE_DEVICE_TABLE(of, orion_spi_of_match_table);
644
645static int orion_spi_probe(struct platform_device *pdev)
646{
647 const struct orion_spi_dev *devdata;
648 struct spi_master *master;
649 struct orion_spi *spi;
650 struct resource *r;
651 unsigned long tclk_hz;
652 int status = 0;
653 struct device_node *np;
654
655 master = spi_alloc_master(&pdev->dev, sizeof(*spi));
656 if (master == NULL) {
657 dev_dbg(&pdev->dev, "master allocation failed\n");
658 return -ENOMEM;
659 }
660
661 if (pdev->id != -1)
662 master->bus_num = pdev->id;
663 if (pdev->dev.of_node) {
664 u32 cell_index;
665
666 if (!of_property_read_u32(pdev->dev.of_node, "cell-index",
667 &cell_index))
668 master->bus_num = cell_index;
669 }
670
671 /* we support all 4 SPI modes and LSB first option */
672 master->mode_bits = SPI_CPHA | SPI_CPOL | SPI_LSB_FIRST | SPI_CS_WORD;
673 master->set_cs = orion_spi_set_cs;
674 master->transfer_one = orion_spi_transfer_one;
675 master->num_chipselect = ORION_NUM_CHIPSELECTS;
676 master->setup = orion_spi_setup;
677 master->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(16);
678 master->auto_runtime_pm = true;
679 master->use_gpio_descriptors = true;
680 master->flags = SPI_MASTER_GPIO_SS;
681
682 platform_set_drvdata(pdev, master);
683
684 spi = spi_master_get_devdata(master);
685 spi->master = master;
686 spi->dev = &pdev->dev;
687
688 devdata = device_get_match_data(&pdev->dev);
689 devdata = devdata ? devdata : &orion_spi_dev_data;
690 spi->devdata = devdata;
691
692 spi->clk = devm_clk_get(&pdev->dev, NULL);
693 if (IS_ERR(spi->clk)) {
694 status = PTR_ERR(spi->clk);
695 goto out;
696 }
697
698 status = clk_prepare_enable(spi->clk);
699 if (status)
700 goto out;
701
702 /* The following clock is only used by some SoCs */
703 spi->axi_clk = devm_clk_get(&pdev->dev, "axi");
704 if (PTR_ERR(spi->axi_clk) == -EPROBE_DEFER) {
705 status = -EPROBE_DEFER;
706 goto out_rel_clk;
707 }
708 if (!IS_ERR(spi->axi_clk))
709 clk_prepare_enable(spi->axi_clk);
710
711 tclk_hz = clk_get_rate(spi->clk);
712
713 /*
714 * With old device tree, armada-370-spi could be used with
715 * Armada XP, however for this SoC the maximum frequency is
716 * 50MHz instead of tclk/4. On Armada 370, tclk cannot be
717 * higher than 200MHz. So, in order to be able to handle both
718 * SoCs, we can take the minimum of 50MHz and tclk/4.
719 */
720 if (of_device_is_compatible(pdev->dev.of_node,
721 "marvell,armada-370-spi"))
722 master->max_speed_hz = min(devdata->max_hz,
723 DIV_ROUND_UP(tclk_hz, devdata->min_divisor));
724 else if (devdata->min_divisor)
725 master->max_speed_hz =
726 DIV_ROUND_UP(tclk_hz, devdata->min_divisor);
727 else
728 master->max_speed_hz = devdata->max_hz;
729 master->min_speed_hz = DIV_ROUND_UP(tclk_hz, devdata->max_divisor);
730
731 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
732 spi->base = devm_ioremap_resource(&pdev->dev, r);
733 if (IS_ERR(spi->base)) {
734 status = PTR_ERR(spi->base);
735 goto out_rel_axi_clk;
736 }
737
738 for_each_available_child_of_node(pdev->dev.of_node, np) {
739 struct orion_direct_acc *dir_acc;
740 u32 cs;
741
742 /* Get chip-select number from the "reg" property */
743 status = of_property_read_u32(np, "reg", &cs);
744 if (status) {
745 dev_err(&pdev->dev,
746 "%pOF has no valid 'reg' property (%d)\n",
747 np, status);
748 continue;
749 }
750
751 /*
752 * Check if an address is configured for this SPI device. If
753 * not, the MBus mapping via the 'ranges' property in the 'soc'
754 * node is not configured and this device should not use the
755 * direct mode. In this case, just continue with the next
756 * device.
757 */
758 status = of_address_to_resource(pdev->dev.of_node, cs + 1, r);
759 if (status)
760 continue;
761
762 /*
763 * Only map one page for direct access. This is enough for the
764 * simple TX transfer which only writes to the first word.
765 * This needs to get extended for the direct SPI NOR / SPI NAND
766 * support, once this gets implemented.
767 */
768 dir_acc = &spi->child[cs].direct_access;
769 dir_acc->vaddr = devm_ioremap(&pdev->dev, r->start, PAGE_SIZE);
770 if (!dir_acc->vaddr) {
771 status = -ENOMEM;
772 of_node_put(np);
773 goto out_rel_axi_clk;
774 }
775 dir_acc->size = PAGE_SIZE;
776
777 dev_info(&pdev->dev, "CS%d configured for direct access\n", cs);
778 }
779
780 pm_runtime_set_active(&pdev->dev);
781 pm_runtime_use_autosuspend(&pdev->dev);
782 pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
783 pm_runtime_enable(&pdev->dev);
784
785 status = orion_spi_reset(spi);
786 if (status < 0)
787 goto out_rel_pm;
788
789 master->dev.of_node = pdev->dev.of_node;
790 status = spi_register_master(master);
791 if (status < 0)
792 goto out_rel_pm;
793
794 return status;
795
796out_rel_pm:
797 pm_runtime_disable(&pdev->dev);
798out_rel_axi_clk:
799 clk_disable_unprepare(spi->axi_clk);
800out_rel_clk:
801 clk_disable_unprepare(spi->clk);
802out:
803 spi_master_put(master);
804 return status;
805}
806
807
808static int orion_spi_remove(struct platform_device *pdev)
809{
810 struct spi_master *master = platform_get_drvdata(pdev);
811 struct orion_spi *spi = spi_master_get_devdata(master);
812
813 pm_runtime_get_sync(&pdev->dev);
814 clk_disable_unprepare(spi->axi_clk);
815 clk_disable_unprepare(spi->clk);
816
817 spi_unregister_master(master);
818 pm_runtime_disable(&pdev->dev);
819
820 return 0;
821}
822
823MODULE_ALIAS("platform:" DRIVER_NAME);
824
825#ifdef CONFIG_PM
826static int orion_spi_runtime_suspend(struct device *dev)
827{
828 struct spi_master *master = dev_get_drvdata(dev);
829 struct orion_spi *spi = spi_master_get_devdata(master);
830
831 clk_disable_unprepare(spi->axi_clk);
832 clk_disable_unprepare(spi->clk);
833 return 0;
834}
835
836static int orion_spi_runtime_resume(struct device *dev)
837{
838 struct spi_master *master = dev_get_drvdata(dev);
839 struct orion_spi *spi = spi_master_get_devdata(master);
840
841 if (!IS_ERR(spi->axi_clk))
842 clk_prepare_enable(spi->axi_clk);
843 return clk_prepare_enable(spi->clk);
844}
845#endif
846
847static const struct dev_pm_ops orion_spi_pm_ops = {
848 SET_RUNTIME_PM_OPS(orion_spi_runtime_suspend,
849 orion_spi_runtime_resume,
850 NULL)
851};
852
853static struct platform_driver orion_spi_driver = {
854 .driver = {
855 .name = DRIVER_NAME,
856 .pm = &orion_spi_pm_ops,
857 .of_match_table = of_match_ptr(orion_spi_of_match_table),
858 },
859 .probe = orion_spi_probe,
860 .remove = orion_spi_remove,
861};
862
863module_platform_driver(orion_spi_driver);
864
865MODULE_DESCRIPTION("Orion SPI driver");
866MODULE_AUTHOR("Shadi Ammouri <shadi@marvell.com>");
867MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Marvell Orion SPI controller driver
4 *
5 * Author: Shadi Ammouri <shadi@marvell.com>
6 * Copyright (C) 2007-2008 Marvell Ltd.
7 */
8
9#include <linux/interrupt.h>
10#include <linux/delay.h>
11#include <linux/platform_device.h>
12#include <linux/err.h>
13#include <linux/io.h>
14#include <linux/spi/spi.h>
15#include <linux/module.h>
16#include <linux/pm_runtime.h>
17#include <linux/of.h>
18#include <linux/of_address.h>
19#include <linux/of_device.h>
20#include <linux/of_gpio.h>
21#include <linux/clk.h>
22#include <linux/sizes.h>
23#include <linux/gpio.h>
24#include <asm/unaligned.h>
25
26#define DRIVER_NAME "orion_spi"
27
28/* Runtime PM autosuspend timeout: PM is fairly light on this driver */
29#define SPI_AUTOSUSPEND_TIMEOUT 200
30
31/* Some SoCs using this driver support up to 8 chip selects.
32 * It is up to the implementer to only use the chip selects
33 * that are available.
34 */
35#define ORION_NUM_CHIPSELECTS 8
36
37#define ORION_SPI_WAIT_RDY_MAX_LOOP 2000 /* in usec */
38
39#define ORION_SPI_IF_CTRL_REG 0x00
40#define ORION_SPI_IF_CONFIG_REG 0x04
41#define ORION_SPI_IF_RXLSBF BIT(14)
42#define ORION_SPI_IF_TXLSBF BIT(13)
43#define ORION_SPI_DATA_OUT_REG 0x08
44#define ORION_SPI_DATA_IN_REG 0x0c
45#define ORION_SPI_INT_CAUSE_REG 0x10
46#define ORION_SPI_TIMING_PARAMS_REG 0x18
47
48/* Register for the "Direct Mode" */
49#define SPI_DIRECT_WRITE_CONFIG_REG 0x20
50
51#define ORION_SPI_TMISO_SAMPLE_MASK (0x3 << 6)
52#define ORION_SPI_TMISO_SAMPLE_1 (1 << 6)
53#define ORION_SPI_TMISO_SAMPLE_2 (2 << 6)
54
55#define ORION_SPI_MODE_CPOL (1 << 11)
56#define ORION_SPI_MODE_CPHA (1 << 12)
57#define ORION_SPI_IF_8_16_BIT_MODE (1 << 5)
58#define ORION_SPI_CLK_PRESCALE_MASK 0x1F
59#define ARMADA_SPI_CLK_PRESCALE_MASK 0xDF
60#define ORION_SPI_MODE_MASK (ORION_SPI_MODE_CPOL | \
61 ORION_SPI_MODE_CPHA)
62#define ORION_SPI_CS_MASK 0x1C
63#define ORION_SPI_CS_SHIFT 2
64#define ORION_SPI_CS(cs) ((cs << ORION_SPI_CS_SHIFT) & \
65 ORION_SPI_CS_MASK)
66
67enum orion_spi_type {
68 ORION_SPI,
69 ARMADA_SPI,
70};
71
72struct orion_spi_dev {
73 enum orion_spi_type typ;
74 /*
75 * min_divisor and max_hz should be exclusive, the only we can
76 * have both is for managing the armada-370-spi case with old
77 * device tree
78 */
79 unsigned long max_hz;
80 unsigned int min_divisor;
81 unsigned int max_divisor;
82 u32 prescale_mask;
83 bool is_errata_50mhz_ac;
84};
85
86struct orion_direct_acc {
87 void __iomem *vaddr;
88 u32 size;
89};
90
91struct orion_child_options {
92 struct orion_direct_acc direct_access;
93};
94
95struct orion_spi {
96 struct spi_master *master;
97 void __iomem *base;
98 struct clk *clk;
99 struct clk *axi_clk;
100 const struct orion_spi_dev *devdata;
101 int unused_hw_gpio;
102
103 struct orion_child_options child[ORION_NUM_CHIPSELECTS];
104};
105
106static inline void __iomem *spi_reg(struct orion_spi *orion_spi, u32 reg)
107{
108 return orion_spi->base + reg;
109}
110
111static inline void
112orion_spi_setbits(struct orion_spi *orion_spi, u32 reg, u32 mask)
113{
114 void __iomem *reg_addr = spi_reg(orion_spi, reg);
115 u32 val;
116
117 val = readl(reg_addr);
118 val |= mask;
119 writel(val, reg_addr);
120}
121
122static inline void
123orion_spi_clrbits(struct orion_spi *orion_spi, u32 reg, u32 mask)
124{
125 void __iomem *reg_addr = spi_reg(orion_spi, reg);
126 u32 val;
127
128 val = readl(reg_addr);
129 val &= ~mask;
130 writel(val, reg_addr);
131}
132
133static int orion_spi_baudrate_set(struct spi_device *spi, unsigned int speed)
134{
135 u32 tclk_hz;
136 u32 rate;
137 u32 prescale;
138 u32 reg;
139 struct orion_spi *orion_spi;
140 const struct orion_spi_dev *devdata;
141
142 orion_spi = spi_master_get_devdata(spi->master);
143 devdata = orion_spi->devdata;
144
145 tclk_hz = clk_get_rate(orion_spi->clk);
146
147 if (devdata->typ == ARMADA_SPI) {
148 /*
149 * Given the core_clk (tclk_hz) and the target rate (speed) we
150 * determine the best values for SPR (in [0 .. 15]) and SPPR (in
151 * [0..7]) such that
152 *
153 * core_clk / (SPR * 2 ** SPPR)
154 *
155 * is as big as possible but not bigger than speed.
156 */
157
158 /* best integer divider: */
159 unsigned divider = DIV_ROUND_UP(tclk_hz, speed);
160 unsigned spr, sppr;
161
162 if (divider < 16) {
163 /* This is the easy case, divider is less than 16 */
164 spr = divider;
165 sppr = 0;
166
167 } else {
168 unsigned two_pow_sppr;
169 /*
170 * Find the highest bit set in divider. This and the
171 * three next bits define SPR (apart from rounding).
172 * SPPR is then the number of zero bits that must be
173 * appended:
174 */
175 sppr = fls(divider) - 4;
176
177 /*
178 * As SPR only has 4 bits, we have to round divider up
179 * to the next multiple of 2 ** sppr.
180 */
181 two_pow_sppr = 1 << sppr;
182 divider = (divider + two_pow_sppr - 1) & -two_pow_sppr;
183
184 /*
185 * recalculate sppr as rounding up divider might have
186 * increased it enough to change the position of the
187 * highest set bit. In this case the bit that now
188 * doesn't make it into SPR is 0, so there is no need to
189 * round again.
190 */
191 sppr = fls(divider) - 4;
192 spr = divider >> sppr;
193
194 /*
195 * Now do range checking. SPR is constructed to have a
196 * width of 4 bits, so this is fine for sure. So we
197 * still need to check for sppr to fit into 3 bits:
198 */
199 if (sppr > 7)
200 return -EINVAL;
201 }
202
203 prescale = ((sppr & 0x6) << 5) | ((sppr & 0x1) << 4) | spr;
204 } else {
205 /*
206 * the supported rates are: 4,6,8...30
207 * round up as we look for equal or less speed
208 */
209 rate = DIV_ROUND_UP(tclk_hz, speed);
210 rate = roundup(rate, 2);
211
212 /* check if requested speed is too small */
213 if (rate > 30)
214 return -EINVAL;
215
216 if (rate < 4)
217 rate = 4;
218
219 /* Convert the rate to SPI clock divisor value. */
220 prescale = 0x10 + rate/2;
221 }
222
223 reg = readl(spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG));
224 reg = ((reg & ~devdata->prescale_mask) | prescale);
225 writel(reg, spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG));
226
227 return 0;
228}
229
230static void
231orion_spi_mode_set(struct spi_device *spi)
232{
233 u32 reg;
234 struct orion_spi *orion_spi;
235
236 orion_spi = spi_master_get_devdata(spi->master);
237
238 reg = readl(spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG));
239 reg &= ~ORION_SPI_MODE_MASK;
240 if (spi->mode & SPI_CPOL)
241 reg |= ORION_SPI_MODE_CPOL;
242 if (spi->mode & SPI_CPHA)
243 reg |= ORION_SPI_MODE_CPHA;
244 if (spi->mode & SPI_LSB_FIRST)
245 reg |= ORION_SPI_IF_RXLSBF | ORION_SPI_IF_TXLSBF;
246 else
247 reg &= ~(ORION_SPI_IF_RXLSBF | ORION_SPI_IF_TXLSBF);
248
249 writel(reg, spi_reg(orion_spi, ORION_SPI_IF_CONFIG_REG));
250}
251
252static void
253orion_spi_50mhz_ac_timing_erratum(struct spi_device *spi, unsigned int speed)
254{
255 u32 reg;
256 struct orion_spi *orion_spi;
257
258 orion_spi = spi_master_get_devdata(spi->master);
259
260 /*
261 * Erratum description: (Erratum NO. FE-9144572) The device
262 * SPI interface supports frequencies of up to 50 MHz.
263 * However, due to this erratum, when the device core clock is
264 * 250 MHz and the SPI interfaces is configured for 50MHz SPI
265 * clock and CPOL=CPHA=1 there might occur data corruption on
266 * reads from the SPI device.
267 * Erratum Workaround:
268 * Work in one of the following configurations:
269 * 1. Set CPOL=CPHA=0 in "SPI Interface Configuration
270 * Register".
271 * 2. Set TMISO_SAMPLE value to 0x2 in "SPI Timing Parameters 1
272 * Register" before setting the interface.
273 */
274 reg = readl(spi_reg(orion_spi, ORION_SPI_TIMING_PARAMS_REG));
275 reg &= ~ORION_SPI_TMISO_SAMPLE_MASK;
276
277 if (clk_get_rate(orion_spi->clk) == 250000000 &&
278 speed == 50000000 && spi->mode & SPI_CPOL &&
279 spi->mode & SPI_CPHA)
280 reg |= ORION_SPI_TMISO_SAMPLE_2;
281 else
282 reg |= ORION_SPI_TMISO_SAMPLE_1; /* This is the default value */
283
284 writel(reg, spi_reg(orion_spi, ORION_SPI_TIMING_PARAMS_REG));
285}
286
287/*
288 * called only when no transfer is active on the bus
289 */
290static int
291orion_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
292{
293 struct orion_spi *orion_spi;
294 unsigned int speed = spi->max_speed_hz;
295 unsigned int bits_per_word = spi->bits_per_word;
296 int rc;
297
298 orion_spi = spi_master_get_devdata(spi->master);
299
300 if ((t != NULL) && t->speed_hz)
301 speed = t->speed_hz;
302
303 if ((t != NULL) && t->bits_per_word)
304 bits_per_word = t->bits_per_word;
305
306 orion_spi_mode_set(spi);
307
308 if (orion_spi->devdata->is_errata_50mhz_ac)
309 orion_spi_50mhz_ac_timing_erratum(spi, speed);
310
311 rc = orion_spi_baudrate_set(spi, speed);
312 if (rc)
313 return rc;
314
315 if (bits_per_word == 16)
316 orion_spi_setbits(orion_spi, ORION_SPI_IF_CONFIG_REG,
317 ORION_SPI_IF_8_16_BIT_MODE);
318 else
319 orion_spi_clrbits(orion_spi, ORION_SPI_IF_CONFIG_REG,
320 ORION_SPI_IF_8_16_BIT_MODE);
321
322 return 0;
323}
324
325static void orion_spi_set_cs(struct spi_device *spi, bool enable)
326{
327 struct orion_spi *orion_spi;
328 int cs;
329
330 orion_spi = spi_master_get_devdata(spi->master);
331
332 if (gpio_is_valid(spi->cs_gpio))
333 cs = orion_spi->unused_hw_gpio;
334 else
335 cs = spi->chip_select;
336
337 orion_spi_clrbits(orion_spi, ORION_SPI_IF_CTRL_REG, ORION_SPI_CS_MASK);
338 orion_spi_setbits(orion_spi, ORION_SPI_IF_CTRL_REG,
339 ORION_SPI_CS(cs));
340
341 /* Chip select logic is inverted from spi_set_cs */
342 if (!enable)
343 orion_spi_setbits(orion_spi, ORION_SPI_IF_CTRL_REG, 0x1);
344 else
345 orion_spi_clrbits(orion_spi, ORION_SPI_IF_CTRL_REG, 0x1);
346}
347
348static inline int orion_spi_wait_till_ready(struct orion_spi *orion_spi)
349{
350 int i;
351
352 for (i = 0; i < ORION_SPI_WAIT_RDY_MAX_LOOP; i++) {
353 if (readl(spi_reg(orion_spi, ORION_SPI_INT_CAUSE_REG)))
354 return 1;
355
356 udelay(1);
357 }
358
359 return -1;
360}
361
362static inline int
363orion_spi_write_read_8bit(struct spi_device *spi,
364 const u8 **tx_buf, u8 **rx_buf)
365{
366 void __iomem *tx_reg, *rx_reg, *int_reg;
367 struct orion_spi *orion_spi;
368
369 orion_spi = spi_master_get_devdata(spi->master);
370 tx_reg = spi_reg(orion_spi, ORION_SPI_DATA_OUT_REG);
371 rx_reg = spi_reg(orion_spi, ORION_SPI_DATA_IN_REG);
372 int_reg = spi_reg(orion_spi, ORION_SPI_INT_CAUSE_REG);
373
374 /* clear the interrupt cause register */
375 writel(0x0, int_reg);
376
377 if (tx_buf && *tx_buf)
378 writel(*(*tx_buf)++, tx_reg);
379 else
380 writel(0, tx_reg);
381
382 if (orion_spi_wait_till_ready(orion_spi) < 0) {
383 dev_err(&spi->dev, "TXS timed out\n");
384 return -1;
385 }
386
387 if (rx_buf && *rx_buf)
388 *(*rx_buf)++ = readl(rx_reg);
389
390 return 1;
391}
392
393static inline int
394orion_spi_write_read_16bit(struct spi_device *spi,
395 const u16 **tx_buf, u16 **rx_buf)
396{
397 void __iomem *tx_reg, *rx_reg, *int_reg;
398 struct orion_spi *orion_spi;
399
400 orion_spi = spi_master_get_devdata(spi->master);
401 tx_reg = spi_reg(orion_spi, ORION_SPI_DATA_OUT_REG);
402 rx_reg = spi_reg(orion_spi, ORION_SPI_DATA_IN_REG);
403 int_reg = spi_reg(orion_spi, ORION_SPI_INT_CAUSE_REG);
404
405 /* clear the interrupt cause register */
406 writel(0x0, int_reg);
407
408 if (tx_buf && *tx_buf)
409 writel(__cpu_to_le16(get_unaligned((*tx_buf)++)), tx_reg);
410 else
411 writel(0, tx_reg);
412
413 if (orion_spi_wait_till_ready(orion_spi) < 0) {
414 dev_err(&spi->dev, "TXS timed out\n");
415 return -1;
416 }
417
418 if (rx_buf && *rx_buf)
419 put_unaligned(__le16_to_cpu(readl(rx_reg)), (*rx_buf)++);
420
421 return 1;
422}
423
424static unsigned int
425orion_spi_write_read(struct spi_device *spi, struct spi_transfer *xfer)
426{
427 unsigned int count;
428 int word_len;
429 struct orion_spi *orion_spi;
430 int cs = spi->chip_select;
431 void __iomem *vaddr;
432
433 word_len = spi->bits_per_word;
434 count = xfer->len;
435
436 orion_spi = spi_master_get_devdata(spi->master);
437
438 /*
439 * Use SPI direct write mode if base address is available. Otherwise
440 * fall back to PIO mode for this transfer.
441 */
442 vaddr = orion_spi->child[cs].direct_access.vaddr;
443
444 if (vaddr && xfer->tx_buf && word_len == 8) {
445 unsigned int cnt = count / 4;
446 unsigned int rem = count % 4;
447
448 /*
449 * Send the TX-data to the SPI device via the direct
450 * mapped address window
451 */
452 iowrite32_rep(vaddr, xfer->tx_buf, cnt);
453 if (rem) {
454 u32 *buf = (u32 *)xfer->tx_buf;
455
456 iowrite8_rep(vaddr, &buf[cnt], rem);
457 }
458
459 return count;
460 }
461
462 if (word_len == 8) {
463 const u8 *tx = xfer->tx_buf;
464 u8 *rx = xfer->rx_buf;
465
466 do {
467 if (orion_spi_write_read_8bit(spi, &tx, &rx) < 0)
468 goto out;
469 count--;
470 if (xfer->word_delay_usecs)
471 udelay(xfer->word_delay_usecs);
472 } while (count);
473 } else if (word_len == 16) {
474 const u16 *tx = xfer->tx_buf;
475 u16 *rx = xfer->rx_buf;
476
477 do {
478 if (orion_spi_write_read_16bit(spi, &tx, &rx) < 0)
479 goto out;
480 count -= 2;
481 if (xfer->word_delay_usecs)
482 udelay(xfer->word_delay_usecs);
483 } while (count);
484 }
485
486out:
487 return xfer->len - count;
488}
489
490static int orion_spi_transfer_one(struct spi_master *master,
491 struct spi_device *spi,
492 struct spi_transfer *t)
493{
494 int status = 0;
495
496 status = orion_spi_setup_transfer(spi, t);
497 if (status < 0)
498 return status;
499
500 if (t->len)
501 orion_spi_write_read(spi, t);
502
503 return status;
504}
505
506static int orion_spi_setup(struct spi_device *spi)
507{
508 if (gpio_is_valid(spi->cs_gpio)) {
509 gpio_direction_output(spi->cs_gpio, !(spi->mode & SPI_CS_HIGH));
510 }
511 return orion_spi_setup_transfer(spi, NULL);
512}
513
514static int orion_spi_reset(struct orion_spi *orion_spi)
515{
516 /* Verify that the CS is deasserted */
517 orion_spi_clrbits(orion_spi, ORION_SPI_IF_CTRL_REG, 0x1);
518
519 /* Don't deassert CS between the direct mapped SPI transfers */
520 writel(0, spi_reg(orion_spi, SPI_DIRECT_WRITE_CONFIG_REG));
521
522 return 0;
523}
524
525static const struct orion_spi_dev orion_spi_dev_data = {
526 .typ = ORION_SPI,
527 .min_divisor = 4,
528 .max_divisor = 30,
529 .prescale_mask = ORION_SPI_CLK_PRESCALE_MASK,
530};
531
532static const struct orion_spi_dev armada_370_spi_dev_data = {
533 .typ = ARMADA_SPI,
534 .min_divisor = 4,
535 .max_divisor = 1920,
536 .max_hz = 50000000,
537 .prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK,
538};
539
540static const struct orion_spi_dev armada_xp_spi_dev_data = {
541 .typ = ARMADA_SPI,
542 .max_hz = 50000000,
543 .max_divisor = 1920,
544 .prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK,
545};
546
547static const struct orion_spi_dev armada_375_spi_dev_data = {
548 .typ = ARMADA_SPI,
549 .min_divisor = 15,
550 .max_divisor = 1920,
551 .prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK,
552};
553
554static const struct orion_spi_dev armada_380_spi_dev_data = {
555 .typ = ARMADA_SPI,
556 .max_hz = 50000000,
557 .max_divisor = 1920,
558 .prescale_mask = ARMADA_SPI_CLK_PRESCALE_MASK,
559 .is_errata_50mhz_ac = true,
560};
561
562static const struct of_device_id orion_spi_of_match_table[] = {
563 {
564 .compatible = "marvell,orion-spi",
565 .data = &orion_spi_dev_data,
566 },
567 {
568 .compatible = "marvell,armada-370-spi",
569 .data = &armada_370_spi_dev_data,
570 },
571 {
572 .compatible = "marvell,armada-375-spi",
573 .data = &armada_375_spi_dev_data,
574 },
575 {
576 .compatible = "marvell,armada-380-spi",
577 .data = &armada_380_spi_dev_data,
578 },
579 {
580 .compatible = "marvell,armada-390-spi",
581 .data = &armada_xp_spi_dev_data,
582 },
583 {
584 .compatible = "marvell,armada-xp-spi",
585 .data = &armada_xp_spi_dev_data,
586 },
587
588 {}
589};
590MODULE_DEVICE_TABLE(of, orion_spi_of_match_table);
591
592static int orion_spi_probe(struct platform_device *pdev)
593{
594 const struct of_device_id *of_id;
595 const struct orion_spi_dev *devdata;
596 struct spi_master *master;
597 struct orion_spi *spi;
598 struct resource *r;
599 unsigned long tclk_hz;
600 int status = 0;
601 struct device_node *np;
602
603 master = spi_alloc_master(&pdev->dev, sizeof(*spi));
604 if (master == NULL) {
605 dev_dbg(&pdev->dev, "master allocation failed\n");
606 return -ENOMEM;
607 }
608
609 if (pdev->id != -1)
610 master->bus_num = pdev->id;
611 if (pdev->dev.of_node) {
612 u32 cell_index;
613
614 if (!of_property_read_u32(pdev->dev.of_node, "cell-index",
615 &cell_index))
616 master->bus_num = cell_index;
617 }
618
619 /* we support all 4 SPI modes and LSB first option */
620 master->mode_bits = SPI_CPHA | SPI_CPOL | SPI_LSB_FIRST;
621 master->set_cs = orion_spi_set_cs;
622 master->transfer_one = orion_spi_transfer_one;
623 master->num_chipselect = ORION_NUM_CHIPSELECTS;
624 master->setup = orion_spi_setup;
625 master->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(16);
626 master->auto_runtime_pm = true;
627 master->flags = SPI_MASTER_GPIO_SS;
628
629 platform_set_drvdata(pdev, master);
630
631 spi = spi_master_get_devdata(master);
632 spi->master = master;
633 spi->unused_hw_gpio = -1;
634
635 of_id = of_match_device(orion_spi_of_match_table, &pdev->dev);
636 devdata = (of_id) ? of_id->data : &orion_spi_dev_data;
637 spi->devdata = devdata;
638
639 spi->clk = devm_clk_get(&pdev->dev, NULL);
640 if (IS_ERR(spi->clk)) {
641 status = PTR_ERR(spi->clk);
642 goto out;
643 }
644
645 status = clk_prepare_enable(spi->clk);
646 if (status)
647 goto out;
648
649 /* The following clock is only used by some SoCs */
650 spi->axi_clk = devm_clk_get(&pdev->dev, "axi");
651 if (IS_ERR(spi->axi_clk) &&
652 PTR_ERR(spi->axi_clk) == -EPROBE_DEFER) {
653 status = -EPROBE_DEFER;
654 goto out_rel_clk;
655 }
656 if (!IS_ERR(spi->axi_clk))
657 clk_prepare_enable(spi->axi_clk);
658
659 tclk_hz = clk_get_rate(spi->clk);
660
661 /*
662 * With old device tree, armada-370-spi could be used with
663 * Armada XP, however for this SoC the maximum frequency is
664 * 50MHz instead of tclk/4. On Armada 370, tclk cannot be
665 * higher than 200MHz. So, in order to be able to handle both
666 * SoCs, we can take the minimum of 50MHz and tclk/4.
667 */
668 if (of_device_is_compatible(pdev->dev.of_node,
669 "marvell,armada-370-spi"))
670 master->max_speed_hz = min(devdata->max_hz,
671 DIV_ROUND_UP(tclk_hz, devdata->min_divisor));
672 else if (devdata->min_divisor)
673 master->max_speed_hz =
674 DIV_ROUND_UP(tclk_hz, devdata->min_divisor);
675 else
676 master->max_speed_hz = devdata->max_hz;
677 master->min_speed_hz = DIV_ROUND_UP(tclk_hz, devdata->max_divisor);
678
679 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
680 spi->base = devm_ioremap_resource(&pdev->dev, r);
681 if (IS_ERR(spi->base)) {
682 status = PTR_ERR(spi->base);
683 goto out_rel_axi_clk;
684 }
685
686 for_each_available_child_of_node(pdev->dev.of_node, np) {
687 struct orion_direct_acc *dir_acc;
688 u32 cs;
689 int cs_gpio;
690
691 /* Get chip-select number from the "reg" property */
692 status = of_property_read_u32(np, "reg", &cs);
693 if (status) {
694 dev_err(&pdev->dev,
695 "%pOF has no valid 'reg' property (%d)\n",
696 np, status);
697 continue;
698 }
699
700 /*
701 * Initialize the CS GPIO:
702 * - properly request the actual GPIO signal
703 * - de-assert the logical signal so that all GPIO CS lines
704 * are inactive when probing for slaves
705 * - find an unused physical CS which will be driven for any
706 * slave which uses a CS GPIO
707 */
708 cs_gpio = of_get_named_gpio(pdev->dev.of_node, "cs-gpios", cs);
709 if (cs_gpio > 0) {
710 char *gpio_name;
711 int cs_flags;
712
713 if (spi->unused_hw_gpio == -1) {
714 dev_info(&pdev->dev,
715 "Selected unused HW CS#%d for any GPIO CSes\n",
716 cs);
717 spi->unused_hw_gpio = cs;
718 }
719
720 gpio_name = devm_kasprintf(&pdev->dev, GFP_KERNEL,
721 "%s-CS%d", dev_name(&pdev->dev), cs);
722 if (!gpio_name) {
723 status = -ENOMEM;
724 goto out_rel_axi_clk;
725 }
726
727 cs_flags = of_property_read_bool(np, "spi-cs-high") ?
728 GPIOF_OUT_INIT_LOW : GPIOF_OUT_INIT_HIGH;
729 status = devm_gpio_request_one(&pdev->dev, cs_gpio,
730 cs_flags, gpio_name);
731 if (status) {
732 dev_err(&pdev->dev,
733 "Can't request GPIO for CS %d\n", cs);
734 goto out_rel_axi_clk;
735 }
736 }
737
738 /*
739 * Check if an address is configured for this SPI device. If
740 * not, the MBus mapping via the 'ranges' property in the 'soc'
741 * node is not configured and this device should not use the
742 * direct mode. In this case, just continue with the next
743 * device.
744 */
745 status = of_address_to_resource(pdev->dev.of_node, cs + 1, r);
746 if (status)
747 continue;
748
749 /*
750 * Only map one page for direct access. This is enough for the
751 * simple TX transfer which only writes to the first word.
752 * This needs to get extended for the direct SPI-NOR / SPI-NAND
753 * support, once this gets implemented.
754 */
755 dir_acc = &spi->child[cs].direct_access;
756 dir_acc->vaddr = devm_ioremap(&pdev->dev, r->start, PAGE_SIZE);
757 if (!dir_acc->vaddr) {
758 status = -ENOMEM;
759 goto out_rel_axi_clk;
760 }
761 dir_acc->size = PAGE_SIZE;
762
763 dev_info(&pdev->dev, "CS%d configured for direct access\n", cs);
764 }
765
766 pm_runtime_set_active(&pdev->dev);
767 pm_runtime_use_autosuspend(&pdev->dev);
768 pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT);
769 pm_runtime_enable(&pdev->dev);
770
771 status = orion_spi_reset(spi);
772 if (status < 0)
773 goto out_rel_pm;
774
775 pm_runtime_mark_last_busy(&pdev->dev);
776 pm_runtime_put_autosuspend(&pdev->dev);
777
778 master->dev.of_node = pdev->dev.of_node;
779 status = spi_register_master(master);
780 if (status < 0)
781 goto out_rel_pm;
782
783 return status;
784
785out_rel_pm:
786 pm_runtime_disable(&pdev->dev);
787out_rel_axi_clk:
788 clk_disable_unprepare(spi->axi_clk);
789out_rel_clk:
790 clk_disable_unprepare(spi->clk);
791out:
792 spi_master_put(master);
793 return status;
794}
795
796
797static int orion_spi_remove(struct platform_device *pdev)
798{
799 struct spi_master *master = platform_get_drvdata(pdev);
800 struct orion_spi *spi = spi_master_get_devdata(master);
801
802 pm_runtime_get_sync(&pdev->dev);
803 clk_disable_unprepare(spi->axi_clk);
804 clk_disable_unprepare(spi->clk);
805
806 spi_unregister_master(master);
807 pm_runtime_disable(&pdev->dev);
808
809 return 0;
810}
811
812MODULE_ALIAS("platform:" DRIVER_NAME);
813
814#ifdef CONFIG_PM
815static int orion_spi_runtime_suspend(struct device *dev)
816{
817 struct spi_master *master = dev_get_drvdata(dev);
818 struct orion_spi *spi = spi_master_get_devdata(master);
819
820 clk_disable_unprepare(spi->axi_clk);
821 clk_disable_unprepare(spi->clk);
822 return 0;
823}
824
825static int orion_spi_runtime_resume(struct device *dev)
826{
827 struct spi_master *master = dev_get_drvdata(dev);
828 struct orion_spi *spi = spi_master_get_devdata(master);
829
830 if (!IS_ERR(spi->axi_clk))
831 clk_prepare_enable(spi->axi_clk);
832 return clk_prepare_enable(spi->clk);
833}
834#endif
835
836static const struct dev_pm_ops orion_spi_pm_ops = {
837 SET_RUNTIME_PM_OPS(orion_spi_runtime_suspend,
838 orion_spi_runtime_resume,
839 NULL)
840};
841
842static struct platform_driver orion_spi_driver = {
843 .driver = {
844 .name = DRIVER_NAME,
845 .pm = &orion_spi_pm_ops,
846 .of_match_table = of_match_ptr(orion_spi_of_match_table),
847 },
848 .probe = orion_spi_probe,
849 .remove = orion_spi_remove,
850};
851
852module_platform_driver(orion_spi_driver);
853
854MODULE_DESCRIPTION("Orion SPI driver");
855MODULE_AUTHOR("Shadi Ammouri <shadi@marvell.com>");
856MODULE_LICENSE("GPL");