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");