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v6.2
  1/*
  2 * Broadcom BCM63XX High Speed SPI Controller driver
  3 *
  4 * Copyright 2000-2010 Broadcom Corporation
  5 * Copyright 2012-2013 Jonas Gorski <jogo@openwrt.org>
  6 *
  7 * Licensed under the GNU/GPL. See COPYING for details.
  8 */
  9
 10#include <linux/kernel.h>
 11#include <linux/init.h>
 12#include <linux/io.h>
 13#include <linux/clk.h>
 14#include <linux/module.h>
 15#include <linux/platform_device.h>
 16#include <linux/delay.h>
 17#include <linux/dma-mapping.h>
 18#include <linux/err.h>
 19#include <linux/interrupt.h>
 20#include <linux/spi/spi.h>
 21#include <linux/mutex.h>
 22#include <linux/of.h>
 
 
 23#include <linux/reset.h>
 24#include <linux/pm_runtime.h>
 25
 26#define HSSPI_GLOBAL_CTRL_REG			0x0
 27#define GLOBAL_CTRL_CS_POLARITY_SHIFT		0
 28#define GLOBAL_CTRL_CS_POLARITY_MASK		0x000000ff
 29#define GLOBAL_CTRL_PLL_CLK_CTRL_SHIFT		8
 30#define GLOBAL_CTRL_PLL_CLK_CTRL_MASK		0x0000ff00
 31#define GLOBAL_CTRL_CLK_GATE_SSOFF		BIT(16)
 32#define GLOBAL_CTRL_CLK_POLARITY		BIT(17)
 33#define GLOBAL_CTRL_MOSI_IDLE			BIT(18)
 34
 35#define HSSPI_GLOBAL_EXT_TRIGGER_REG		0x4
 36
 37#define HSSPI_INT_STATUS_REG			0x8
 38#define HSSPI_INT_STATUS_MASKED_REG		0xc
 39#define HSSPI_INT_MASK_REG			0x10
 40
 41#define HSSPI_PINGx_CMD_DONE(i)			BIT((i * 8) + 0)
 42#define HSSPI_PINGx_RX_OVER(i)			BIT((i * 8) + 1)
 43#define HSSPI_PINGx_TX_UNDER(i)			BIT((i * 8) + 2)
 44#define HSSPI_PINGx_POLL_TIMEOUT(i)		BIT((i * 8) + 3)
 45#define HSSPI_PINGx_CTRL_INVAL(i)		BIT((i * 8) + 4)
 46
 47#define HSSPI_INT_CLEAR_ALL			0xff001f1f
 48
 49#define HSSPI_PINGPONG_COMMAND_REG(x)		(0x80 + (x) * 0x40)
 50#define PINGPONG_CMD_COMMAND_MASK		0xf
 51#define PINGPONG_COMMAND_NOOP			0
 52#define PINGPONG_COMMAND_START_NOW		1
 53#define PINGPONG_COMMAND_START_TRIGGER		2
 54#define PINGPONG_COMMAND_HALT			3
 55#define PINGPONG_COMMAND_FLUSH			4
 56#define PINGPONG_CMD_PROFILE_SHIFT		8
 57#define PINGPONG_CMD_SS_SHIFT			12
 58
 59#define HSSPI_PINGPONG_STATUS_REG(x)		(0x84 + (x) * 0x40)
 
 60
 61#define HSSPI_PROFILE_CLK_CTRL_REG(x)		(0x100 + (x) * 0x20)
 62#define CLK_CTRL_FREQ_CTRL_MASK			0x0000ffff
 63#define CLK_CTRL_SPI_CLK_2X_SEL			BIT(14)
 64#define CLK_CTRL_ACCUM_RST_ON_LOOP		BIT(15)
 65
 66#define HSSPI_PROFILE_SIGNAL_CTRL_REG(x)	(0x104 + (x) * 0x20)
 67#define SIGNAL_CTRL_LATCH_RISING		BIT(12)
 68#define SIGNAL_CTRL_LAUNCH_RISING		BIT(13)
 69#define SIGNAL_CTRL_ASYNC_INPUT_PATH		BIT(16)
 70
 71#define HSSPI_PROFILE_MODE_CTRL_REG(x)		(0x108 + (x) * 0x20)
 72#define MODE_CTRL_MULTIDATA_RD_STRT_SHIFT	8
 73#define MODE_CTRL_MULTIDATA_WR_STRT_SHIFT	12
 74#define MODE_CTRL_MULTIDATA_RD_SIZE_SHIFT	16
 75#define MODE_CTRL_MULTIDATA_WR_SIZE_SHIFT	18
 76#define MODE_CTRL_MODE_3WIRE			BIT(20)
 77#define MODE_CTRL_PREPENDBYTE_CNT_SHIFT		24
 78
 79#define HSSPI_FIFO_REG(x)			(0x200 + (x) * 0x200)
 80
 81
 82#define HSSPI_OP_MULTIBIT			BIT(11)
 83#define HSSPI_OP_CODE_SHIFT			13
 84#define HSSPI_OP_SLEEP				(0 << HSSPI_OP_CODE_SHIFT)
 85#define HSSPI_OP_READ_WRITE			(1 << HSSPI_OP_CODE_SHIFT)
 86#define HSSPI_OP_WRITE				(2 << HSSPI_OP_CODE_SHIFT)
 87#define HSSPI_OP_READ				(3 << HSSPI_OP_CODE_SHIFT)
 88#define HSSPI_OP_SETIRQ				(4 << HSSPI_OP_CODE_SHIFT)
 89
 90#define HSSPI_BUFFER_LEN			512
 91#define HSSPI_OPCODE_LEN			2
 92
 93#define HSSPI_MAX_PREPEND_LEN			15
 94
 95#define HSSPI_MAX_SYNC_CLOCK			30000000
 
 
 
 
 96
 97#define HSSPI_SPI_MAX_CS			8
 98#define HSSPI_BUS_NUM				1 /* 0 is legacy SPI */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 99
100struct bcm63xx_hsspi {
101	struct completion done;
102	struct mutex bus_mutex;
103
104	struct platform_device *pdev;
105	struct clk *clk;
106	struct clk *pll_clk;
107	void __iomem *regs;
108	u8 __iomem *fifo;
109
110	u32 speed_hz;
111	u8 cs_polarity;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
112};
113
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
114static void bcm63xx_hsspi_set_cs(struct bcm63xx_hsspi *bs, unsigned int cs,
115				 bool active)
116{
117	u32 reg;
118
119	mutex_lock(&bs->bus_mutex);
120	reg = __raw_readl(bs->regs + HSSPI_GLOBAL_CTRL_REG);
121
122	reg &= ~BIT(cs);
123	if (active == !(bs->cs_polarity & BIT(cs)))
124		reg |= BIT(cs);
125
126	__raw_writel(reg, bs->regs + HSSPI_GLOBAL_CTRL_REG);
127	mutex_unlock(&bs->bus_mutex);
128}
129
130static void bcm63xx_hsspi_set_clk(struct bcm63xx_hsspi *bs,
131				  struct spi_device *spi, int hz)
132{
133	unsigned int profile = spi->chip_select;
134	u32 reg;
135
136	reg = DIV_ROUND_UP(2048, DIV_ROUND_UP(bs->speed_hz, hz));
137	__raw_writel(CLK_CTRL_ACCUM_RST_ON_LOOP | reg,
138		     bs->regs + HSSPI_PROFILE_CLK_CTRL_REG(profile));
139
140	reg = __raw_readl(bs->regs + HSSPI_PROFILE_SIGNAL_CTRL_REG(profile));
141	if (hz > HSSPI_MAX_SYNC_CLOCK)
142		reg |= SIGNAL_CTRL_ASYNC_INPUT_PATH;
143	else
144		reg &= ~SIGNAL_CTRL_ASYNC_INPUT_PATH;
145	__raw_writel(reg, bs->regs + HSSPI_PROFILE_SIGNAL_CTRL_REG(profile));
146
147	mutex_lock(&bs->bus_mutex);
148	/* setup clock polarity */
149	reg = __raw_readl(bs->regs + HSSPI_GLOBAL_CTRL_REG);
150	reg &= ~GLOBAL_CTRL_CLK_POLARITY;
151	if (spi->mode & SPI_CPOL)
152		reg |= GLOBAL_CTRL_CLK_POLARITY;
153	__raw_writel(reg, bs->regs + HSSPI_GLOBAL_CTRL_REG);
154	mutex_unlock(&bs->bus_mutex);
155}
156
157static int bcm63xx_hsspi_do_txrx(struct spi_device *spi, struct spi_transfer *t)
158{
159	struct bcm63xx_hsspi *bs = spi_master_get_devdata(spi->master);
160	unsigned int chip_select = spi->chip_select;
161	u16 opcode = 0;
162	int pending = t->len;
163	int step_size = HSSPI_BUFFER_LEN;
164	const u8 *tx = t->tx_buf;
165	u8 *rx = t->rx_buf;
 
166
167	bcm63xx_hsspi_set_clk(bs, spi, t->speed_hz);
168	bcm63xx_hsspi_set_cs(bs, spi->chip_select, true);
 
169
170	if (tx && rx)
171		opcode = HSSPI_OP_READ_WRITE;
172	else if (tx)
173		opcode = HSSPI_OP_WRITE;
174	else if (rx)
175		opcode = HSSPI_OP_READ;
176
177	if (opcode != HSSPI_OP_READ)
178		step_size -= HSSPI_OPCODE_LEN;
179
180	if ((opcode == HSSPI_OP_READ && t->rx_nbits == SPI_NBITS_DUAL) ||
181	    (opcode == HSSPI_OP_WRITE && t->tx_nbits == SPI_NBITS_DUAL))
182		opcode |= HSSPI_OP_MULTIBIT;
183
184	__raw_writel(1 << MODE_CTRL_MULTIDATA_WR_SIZE_SHIFT |
185		     1 << MODE_CTRL_MULTIDATA_RD_SIZE_SHIFT | 0xff,
 
 
 
 
 
186		     bs->regs + HSSPI_PROFILE_MODE_CTRL_REG(chip_select));
187
188	while (pending > 0) {
189		int curr_step = min_t(int, step_size, pending);
190
191		reinit_completion(&bs->done);
192		if (tx) {
193			memcpy_toio(bs->fifo + HSSPI_OPCODE_LEN, tx, curr_step);
194			tx += curr_step;
195		}
196
197		__raw_writew(opcode | curr_step, bs->fifo);
 
198
199		/* enable interrupt */
200		__raw_writel(HSSPI_PINGx_CMD_DONE(0),
201			     bs->regs + HSSPI_INT_MASK_REG);
202
203		/* start the transfer */
204		__raw_writel(!chip_select << PINGPONG_CMD_SS_SHIFT |
205			     chip_select << PINGPONG_CMD_PROFILE_SHIFT |
206			     PINGPONG_COMMAND_START_NOW,
207			     bs->regs + HSSPI_PINGPONG_COMMAND_REG(0));
208
209		if (wait_for_completion_timeout(&bs->done, HZ) == 0) {
210			dev_err(&bs->pdev->dev, "transfer timed out!\n");
211			return -ETIMEDOUT;
212		}
213
214		if (rx) {
215			memcpy_fromio(rx, bs->fifo, curr_step);
216			rx += curr_step;
217		}
218
219		pending -= curr_step;
220	}
221
222	return 0;
223}
224
225static int bcm63xx_hsspi_setup(struct spi_device *spi)
226{
227	struct bcm63xx_hsspi *bs = spi_master_get_devdata(spi->master);
228	u32 reg;
229
230	reg = __raw_readl(bs->regs +
231			  HSSPI_PROFILE_SIGNAL_CTRL_REG(spi->chip_select));
232	reg &= ~(SIGNAL_CTRL_LAUNCH_RISING | SIGNAL_CTRL_LATCH_RISING);
233	if (spi->mode & SPI_CPHA)
234		reg |= SIGNAL_CTRL_LAUNCH_RISING;
235	else
236		reg |= SIGNAL_CTRL_LATCH_RISING;
237	__raw_writel(reg, bs->regs +
238		     HSSPI_PROFILE_SIGNAL_CTRL_REG(spi->chip_select));
239
240	mutex_lock(&bs->bus_mutex);
241	reg = __raw_readl(bs->regs + HSSPI_GLOBAL_CTRL_REG);
242
243	/* only change actual polarities if there is no transfer */
244	if ((reg & GLOBAL_CTRL_CS_POLARITY_MASK) == bs->cs_polarity) {
245		if (spi->mode & SPI_CS_HIGH)
246			reg |= BIT(spi->chip_select);
247		else
248			reg &= ~BIT(spi->chip_select);
249		__raw_writel(reg, bs->regs + HSSPI_GLOBAL_CTRL_REG);
250	}
251
252	if (spi->mode & SPI_CS_HIGH)
253		bs->cs_polarity |= BIT(spi->chip_select);
254	else
255		bs->cs_polarity &= ~BIT(spi->chip_select);
256
257	mutex_unlock(&bs->bus_mutex);
258
259	return 0;
260}
261
262static int bcm63xx_hsspi_transfer_one(struct spi_master *master,
263				      struct spi_message *msg)
264{
265	struct bcm63xx_hsspi *bs = spi_master_get_devdata(master);
266	struct spi_transfer *t;
267	struct spi_device *spi = msg->spi;
268	int status = -EINVAL;
269	int dummy_cs;
270	u32 reg;
 
271
272	/* This controller does not support keeping CS active during idle.
 
273	 * To work around this, we use the following ugly hack:
274	 *
275	 * a. Invert the target chip select's polarity so it will be active.
276	 * b. Select a "dummy" chip select to use as the hardware target.
277	 * c. Invert the dummy chip select's polarity so it will be inactive
278	 *    during the actual transfers.
279	 * d. Tell the hardware to send to the dummy chip select. Thanks to
280	 *    the multiplexed nature of SPI the actual target will receive
281	 *    the transfer and we see its response.
282	 *
283	 * e. At the end restore the polarities again to their default values.
284	 */
285
286	dummy_cs = !spi->chip_select;
287	bcm63xx_hsspi_set_cs(bs, dummy_cs, true);
288
289	list_for_each_entry(t, &msg->transfers, transfer_list) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
290		status = bcm63xx_hsspi_do_txrx(spi, t);
291		if (status)
292			break;
293
294		msg->actual_length += t->len;
295
296		spi_transfer_delay_exec(t);
297
298		if (t->cs_change)
299			bcm63xx_hsspi_set_cs(bs, spi->chip_select, false);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
300	}
301
302	mutex_lock(&bs->bus_mutex);
303	reg = __raw_readl(bs->regs + HSSPI_GLOBAL_CTRL_REG);
304	reg &= ~GLOBAL_CTRL_CS_POLARITY_MASK;
305	reg |= bs->cs_polarity;
306	__raw_writel(reg, bs->regs + HSSPI_GLOBAL_CTRL_REG);
307	mutex_unlock(&bs->bus_mutex);
 
 
 
 
 
 
 
 
 
308
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
309	msg->status = status;
310	spi_finalize_current_message(master);
311
312	return 0;
313}
314
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
315static irqreturn_t bcm63xx_hsspi_interrupt(int irq, void *dev_id)
316{
317	struct bcm63xx_hsspi *bs = (struct bcm63xx_hsspi *)dev_id;
318
319	if (__raw_readl(bs->regs + HSSPI_INT_STATUS_MASKED_REG) == 0)
320		return IRQ_NONE;
321
322	__raw_writel(HSSPI_INT_CLEAR_ALL, bs->regs + HSSPI_INT_STATUS_REG);
323	__raw_writel(0, bs->regs + HSSPI_INT_MASK_REG);
324
325	complete(&bs->done);
326
327	return IRQ_HANDLED;
328}
329
330static int bcm63xx_hsspi_probe(struct platform_device *pdev)
331{
332	struct spi_master *master;
333	struct bcm63xx_hsspi *bs;
334	void __iomem *regs;
335	struct device *dev = &pdev->dev;
336	struct clk *clk, *pll_clk = NULL;
337	int irq, ret;
338	u32 reg, rate, num_cs = HSSPI_SPI_MAX_CS;
339	struct reset_control *reset;
340
341	irq = platform_get_irq(pdev, 0);
342	if (irq < 0)
343		return irq;
344
345	regs = devm_platform_ioremap_resource(pdev, 0);
346	if (IS_ERR(regs))
347		return PTR_ERR(regs);
348
349	clk = devm_clk_get(dev, "hsspi");
350
351	if (IS_ERR(clk))
352		return PTR_ERR(clk);
353
354	reset = devm_reset_control_get_optional_exclusive(dev, NULL);
355	if (IS_ERR(reset))
356		return PTR_ERR(reset);
357
358	ret = clk_prepare_enable(clk);
359	if (ret)
360		return ret;
361
362	ret = reset_control_reset(reset);
363	if (ret) {
364		dev_err(dev, "unable to reset device: %d\n", ret);
365		goto out_disable_clk;
366	}
367
368	rate = clk_get_rate(clk);
369	if (!rate) {
370		pll_clk = devm_clk_get(dev, "pll");
371
372		if (IS_ERR(pll_clk)) {
373			ret = PTR_ERR(pll_clk);
374			goto out_disable_clk;
375		}
376
377		ret = clk_prepare_enable(pll_clk);
378		if (ret)
379			goto out_disable_clk;
380
381		rate = clk_get_rate(pll_clk);
382		if (!rate) {
383			ret = -EINVAL;
384			goto out_disable_pll_clk;
385		}
386	}
387
388	master = spi_alloc_master(&pdev->dev, sizeof(*bs));
389	if (!master) {
390		ret = -ENOMEM;
391		goto out_disable_pll_clk;
392	}
393
394	bs = spi_master_get_devdata(master);
395	bs->pdev = pdev;
396	bs->clk = clk;
397	bs->pll_clk = pll_clk;
398	bs->regs = regs;
399	bs->speed_hz = rate;
400	bs->fifo = (u8 __iomem *)(bs->regs + HSSPI_FIFO_REG(0));
 
 
 
 
 
 
401
402	mutex_init(&bs->bus_mutex);
 
403	init_completion(&bs->done);
404
405	master->dev.of_node = dev->of_node;
 
406	if (!dev->of_node)
407		master->bus_num = HSSPI_BUS_NUM;
408
409	of_property_read_u32(dev->of_node, "num-cs", &num_cs);
410	if (num_cs > 8) {
411		dev_warn(dev, "unsupported number of cs (%i), reducing to 8\n",
412			 num_cs);
413		num_cs = HSSPI_SPI_MAX_CS;
414	}
415	master->num_chipselect = num_cs;
416	master->setup = bcm63xx_hsspi_setup;
417	master->transfer_one_message = bcm63xx_hsspi_transfer_one;
418	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH |
 
 
 
419			    SPI_RX_DUAL | SPI_TX_DUAL;
420	master->bits_per_word_mask = SPI_BPW_MASK(8);
421	master->auto_runtime_pm = true;
422
423	platform_set_drvdata(pdev, master);
424
425	/* Initialize the hardware */
426	__raw_writel(0, bs->regs + HSSPI_INT_MASK_REG);
427
428	/* clean up any pending interrupts */
429	__raw_writel(HSSPI_INT_CLEAR_ALL, bs->regs + HSSPI_INT_STATUS_REG);
430
431	/* read out default CS polarities */
432	reg = __raw_readl(bs->regs + HSSPI_GLOBAL_CTRL_REG);
433	bs->cs_polarity = reg & GLOBAL_CTRL_CS_POLARITY_MASK;
434	__raw_writel(reg | GLOBAL_CTRL_CLK_GATE_SSOFF,
435		     bs->regs + HSSPI_GLOBAL_CTRL_REG);
436
437	ret = devm_request_irq(dev, irq, bcm63xx_hsspi_interrupt, IRQF_SHARED,
438			       pdev->name, bs);
 
439
440	if (ret)
441		goto out_put_master;
 
442
443	pm_runtime_enable(&pdev->dev);
444
 
 
 
 
 
 
445	/* register and we are done */
446	ret = devm_spi_register_master(dev, master);
447	if (ret)
448		goto out_pm_disable;
 
 
449
450	return 0;
451
 
 
452out_pm_disable:
453	pm_runtime_disable(&pdev->dev);
454out_put_master:
455	spi_master_put(master);
456out_disable_pll_clk:
457	clk_disable_unprepare(pll_clk);
458out_disable_clk:
459	clk_disable_unprepare(clk);
460	return ret;
461}
462
463
464static int bcm63xx_hsspi_remove(struct platform_device *pdev)
465{
466	struct spi_master *master = platform_get_drvdata(pdev);
467	struct bcm63xx_hsspi *bs = spi_master_get_devdata(master);
468
469	/* reset the hardware and block queue progress */
470	__raw_writel(0, bs->regs + HSSPI_INT_MASK_REG);
471	clk_disable_unprepare(bs->pll_clk);
472	clk_disable_unprepare(bs->clk);
473
474	return 0;
475}
476
477#ifdef CONFIG_PM_SLEEP
478static int bcm63xx_hsspi_suspend(struct device *dev)
479{
480	struct spi_master *master = dev_get_drvdata(dev);
481	struct bcm63xx_hsspi *bs = spi_master_get_devdata(master);
482
483	spi_master_suspend(master);
484	clk_disable_unprepare(bs->pll_clk);
485	clk_disable_unprepare(bs->clk);
486
487	return 0;
488}
489
490static int bcm63xx_hsspi_resume(struct device *dev)
491{
492	struct spi_master *master = dev_get_drvdata(dev);
493	struct bcm63xx_hsspi *bs = spi_master_get_devdata(master);
494	int ret;
495
496	ret = clk_prepare_enable(bs->clk);
497	if (ret)
498		return ret;
499
500	if (bs->pll_clk) {
501		ret = clk_prepare_enable(bs->pll_clk);
502		if (ret) {
503			clk_disable_unprepare(bs->clk);
504			return ret;
505		}
506	}
507
508	spi_master_resume(master);
509
510	return 0;
511}
512#endif
513
514static SIMPLE_DEV_PM_OPS(bcm63xx_hsspi_pm_ops, bcm63xx_hsspi_suspend,
515			 bcm63xx_hsspi_resume);
516
517static const struct of_device_id bcm63xx_hsspi_of_match[] = {
518	{ .compatible = "brcm,bcm6328-hsspi", },
 
519	{ },
520};
521MODULE_DEVICE_TABLE(of, bcm63xx_hsspi_of_match);
522
523static struct platform_driver bcm63xx_hsspi_driver = {
524	.driver = {
525		.name	= "bcm63xx-hsspi",
526		.pm	= &bcm63xx_hsspi_pm_ops,
527		.of_match_table = bcm63xx_hsspi_of_match,
528	},
529	.probe		= bcm63xx_hsspi_probe,
530	.remove		= bcm63xx_hsspi_remove,
531};
532
533module_platform_driver(bcm63xx_hsspi_driver);
534
535MODULE_ALIAS("platform:bcm63xx_hsspi");
536MODULE_DESCRIPTION("Broadcom BCM63xx High Speed SPI Controller driver");
537MODULE_AUTHOR("Jonas Gorski <jogo@openwrt.org>");
538MODULE_LICENSE("GPL");
v6.9.4
  1/*
  2 * Broadcom BCM63XX High Speed SPI Controller driver
  3 *
  4 * Copyright 2000-2010 Broadcom Corporation
  5 * Copyright 2012-2013 Jonas Gorski <jonas.gorski@gmail.com>
  6 *
  7 * Licensed under the GNU/GPL. See COPYING for details.
  8 */
  9
 10#include <linux/kernel.h>
 11#include <linux/init.h>
 12#include <linux/io.h>
 13#include <linux/clk.h>
 14#include <linux/module.h>
 15#include <linux/platform_device.h>
 16#include <linux/delay.h>
 17#include <linux/dma-mapping.h>
 18#include <linux/err.h>
 19#include <linux/interrupt.h>
 20#include <linux/spi/spi.h>
 21#include <linux/mutex.h>
 22#include <linux/of.h>
 23#include <linux/spi/spi-mem.h>
 24#include <linux/mtd/spi-nor.h>
 25#include <linux/reset.h>
 26#include <linux/pm_runtime.h>
 27
 28#define HSSPI_GLOBAL_CTRL_REG			0x0
 29#define GLOBAL_CTRL_CS_POLARITY_SHIFT		0
 30#define GLOBAL_CTRL_CS_POLARITY_MASK		0x000000ff
 31#define GLOBAL_CTRL_PLL_CLK_CTRL_SHIFT		8
 32#define GLOBAL_CTRL_PLL_CLK_CTRL_MASK		0x0000ff00
 33#define GLOBAL_CTRL_CLK_GATE_SSOFF		BIT(16)
 34#define GLOBAL_CTRL_CLK_POLARITY		BIT(17)
 35#define GLOBAL_CTRL_MOSI_IDLE			BIT(18)
 36
 37#define HSSPI_GLOBAL_EXT_TRIGGER_REG		0x4
 38
 39#define HSSPI_INT_STATUS_REG			0x8
 40#define HSSPI_INT_STATUS_MASKED_REG		0xc
 41#define HSSPI_INT_MASK_REG			0x10
 42
 43#define HSSPI_PINGx_CMD_DONE(i)			BIT((i * 8) + 0)
 44#define HSSPI_PINGx_RX_OVER(i)			BIT((i * 8) + 1)
 45#define HSSPI_PINGx_TX_UNDER(i)			BIT((i * 8) + 2)
 46#define HSSPI_PINGx_POLL_TIMEOUT(i)		BIT((i * 8) + 3)
 47#define HSSPI_PINGx_CTRL_INVAL(i)		BIT((i * 8) + 4)
 48
 49#define HSSPI_INT_CLEAR_ALL			0xff001f1f
 50
 51#define HSSPI_PINGPONG_COMMAND_REG(x)		(0x80 + (x) * 0x40)
 52#define PINGPONG_CMD_COMMAND_MASK		0xf
 53#define PINGPONG_COMMAND_NOOP			0
 54#define PINGPONG_COMMAND_START_NOW		1
 55#define PINGPONG_COMMAND_START_TRIGGER		2
 56#define PINGPONG_COMMAND_HALT			3
 57#define PINGPONG_COMMAND_FLUSH			4
 58#define PINGPONG_CMD_PROFILE_SHIFT		8
 59#define PINGPONG_CMD_SS_SHIFT			12
 60
 61#define HSSPI_PINGPONG_STATUS_REG(x)		(0x84 + (x) * 0x40)
 62#define HSSPI_PINGPONG_STATUS_SRC_BUSY		BIT(1)
 63
 64#define HSSPI_PROFILE_CLK_CTRL_REG(x)		(0x100 + (x) * 0x20)
 65#define CLK_CTRL_FREQ_CTRL_MASK			0x0000ffff
 66#define CLK_CTRL_SPI_CLK_2X_SEL			BIT(14)
 67#define CLK_CTRL_ACCUM_RST_ON_LOOP		BIT(15)
 68
 69#define HSSPI_PROFILE_SIGNAL_CTRL_REG(x)	(0x104 + (x) * 0x20)
 70#define SIGNAL_CTRL_LATCH_RISING		BIT(12)
 71#define SIGNAL_CTRL_LAUNCH_RISING		BIT(13)
 72#define SIGNAL_CTRL_ASYNC_INPUT_PATH		BIT(16)
 73
 74#define HSSPI_PROFILE_MODE_CTRL_REG(x)		(0x108 + (x) * 0x20)
 75#define MODE_CTRL_MULTIDATA_RD_STRT_SHIFT	8
 76#define MODE_CTRL_MULTIDATA_WR_STRT_SHIFT	12
 77#define MODE_CTRL_MULTIDATA_RD_SIZE_SHIFT	16
 78#define MODE_CTRL_MULTIDATA_WR_SIZE_SHIFT	18
 79#define MODE_CTRL_MODE_3WIRE			BIT(20)
 80#define MODE_CTRL_PREPENDBYTE_CNT_SHIFT		24
 81
 82#define HSSPI_FIFO_REG(x)			(0x200 + (x) * 0x200)
 83
 84
 85#define HSSPI_OP_MULTIBIT			BIT(11)
 86#define HSSPI_OP_CODE_SHIFT			13
 87#define HSSPI_OP_SLEEP				(0 << HSSPI_OP_CODE_SHIFT)
 88#define HSSPI_OP_READ_WRITE			(1 << HSSPI_OP_CODE_SHIFT)
 89#define HSSPI_OP_WRITE				(2 << HSSPI_OP_CODE_SHIFT)
 90#define HSSPI_OP_READ				(3 << HSSPI_OP_CODE_SHIFT)
 91#define HSSPI_OP_SETIRQ				(4 << HSSPI_OP_CODE_SHIFT)
 92
 93#define HSSPI_BUFFER_LEN			512
 94#define HSSPI_OPCODE_LEN			2
 95
 96#define HSSPI_MAX_PREPEND_LEN			15
 97
 98/*
 99 * Some chip require 30MHz but other require 25MHz. Use smaller value to cover
100 * both cases.
101 */
102#define HSSPI_MAX_SYNC_CLOCK			25000000
103
104#define HSSPI_SPI_MAX_CS			8
105#define HSSPI_BUS_NUM				1 /* 0 is legacy SPI */
106#define HSSPI_POLL_STATUS_TIMEOUT_MS	100
107
108#define HSSPI_WAIT_MODE_POLLING		0
109#define HSSPI_WAIT_MODE_INTR		1
110#define HSSPI_WAIT_MODE_MAX			HSSPI_WAIT_MODE_INTR
111
112/*
113 * Default transfer mode is auto. If the msg is prependable, use the prepend
114 * mode.  If not, falls back to use the dummy cs workaround mode but limit the
115 * clock to 25MHz to make sure it works in all board design.
116 */
117#define HSSPI_XFER_MODE_AUTO		0
118#define HSSPI_XFER_MODE_PREPEND		1
119#define HSSPI_XFER_MODE_DUMMYCS		2
120#define HSSPI_XFER_MODE_MAX			HSSPI_XFER_MODE_DUMMYCS
121
122#define bcm63xx_prepend_printk_on_checkfail(bs, fmt, ...)	\
123do {										\
124	if (bs->xfer_mode == HSSPI_XFER_MODE_AUTO)				\
125		dev_dbg(&bs->pdev->dev, fmt, ##__VA_ARGS__);		\
126	else if (bs->xfer_mode == HSSPI_XFER_MODE_PREPEND)		\
127		dev_err(&bs->pdev->dev, fmt, ##__VA_ARGS__);		\
128} while (0)
129
130struct bcm63xx_hsspi {
131	struct completion done;
132	struct mutex bus_mutex;
133	struct mutex msg_mutex;
134	struct platform_device *pdev;
135	struct clk *clk;
136	struct clk *pll_clk;
137	void __iomem *regs;
138	u8 __iomem *fifo;
139
140	u32 speed_hz;
141	u8 cs_polarity;
142	u32 wait_mode;
143	u32 xfer_mode;
144	u32 prepend_cnt;
145	u8 *prepend_buf;
146};
147
148static ssize_t wait_mode_show(struct device *dev, struct device_attribute *attr,
149			 char *buf)
150{
151	struct spi_controller *ctrl = dev_get_drvdata(dev);
152	struct bcm63xx_hsspi *bs = spi_controller_get_devdata(ctrl);
153
154	return sprintf(buf, "%d\n", bs->wait_mode);
155}
156
157static ssize_t wait_mode_store(struct device *dev, struct device_attribute *attr,
158			  const char *buf, size_t count)
159{
160	struct spi_controller *ctrl = dev_get_drvdata(dev);
161	struct bcm63xx_hsspi *bs = spi_controller_get_devdata(ctrl);
162	u32 val;
163
164	if (kstrtou32(buf, 10, &val))
165		return -EINVAL;
166
167	if (val > HSSPI_WAIT_MODE_MAX) {
168		dev_warn(dev, "invalid wait mode %u\n", val);
169		return -EINVAL;
170	}
171
172	mutex_lock(&bs->msg_mutex);
173	bs->wait_mode = val;
174	/* clear interrupt status to avoid spurious int on next transfer */
175	if (val == HSSPI_WAIT_MODE_INTR)
176		__raw_writel(HSSPI_INT_CLEAR_ALL, bs->regs + HSSPI_INT_STATUS_REG);
177	mutex_unlock(&bs->msg_mutex);
178
179	return count;
180}
181
182static DEVICE_ATTR_RW(wait_mode);
183
184static ssize_t xfer_mode_show(struct device *dev, struct device_attribute *attr,
185			 char *buf)
186{
187	struct spi_controller *ctrl = dev_get_drvdata(dev);
188	struct bcm63xx_hsspi *bs = spi_controller_get_devdata(ctrl);
189
190	return sprintf(buf, "%d\n", bs->xfer_mode);
191}
192
193static ssize_t xfer_mode_store(struct device *dev, struct device_attribute *attr,
194			  const char *buf, size_t count)
195{
196	struct spi_controller *ctrl = dev_get_drvdata(dev);
197	struct bcm63xx_hsspi *bs = spi_controller_get_devdata(ctrl);
198	u32 val;
199
200	if (kstrtou32(buf, 10, &val))
201		return -EINVAL;
202
203	if (val > HSSPI_XFER_MODE_MAX) {
204		dev_warn(dev, "invalid xfer mode %u\n", val);
205		return -EINVAL;
206	}
207
208	mutex_lock(&bs->msg_mutex);
209	bs->xfer_mode = val;
210	mutex_unlock(&bs->msg_mutex);
211
212	return count;
213}
214
215static DEVICE_ATTR_RW(xfer_mode);
216
217static struct attribute *bcm63xx_hsspi_attrs[] = {
218	&dev_attr_wait_mode.attr,
219	&dev_attr_xfer_mode.attr,
220	NULL,
221};
222
223static const struct attribute_group bcm63xx_hsspi_group = {
224	.attrs = bcm63xx_hsspi_attrs,
225};
226
227static void bcm63xx_hsspi_set_clk(struct bcm63xx_hsspi *bs,
228				  struct spi_device *spi, int hz);
229
230static size_t bcm63xx_hsspi_max_message_size(struct spi_device *spi)
231{
232	return HSSPI_BUFFER_LEN - HSSPI_OPCODE_LEN;
233}
234
235static int bcm63xx_hsspi_wait_cmd(struct bcm63xx_hsspi *bs)
236{
237	unsigned long limit;
238	u32 reg = 0;
239	int rc = 0;
240
241	if (bs->wait_mode == HSSPI_WAIT_MODE_INTR) {
242		if (wait_for_completion_timeout(&bs->done, HZ) == 0)
243			rc = 1;
244	} else {
245		/* polling mode checks for status busy bit */
246		limit = jiffies + msecs_to_jiffies(HSSPI_POLL_STATUS_TIMEOUT_MS);
247
248		while (!time_after(jiffies, limit)) {
249			reg = __raw_readl(bs->regs + HSSPI_PINGPONG_STATUS_REG(0));
250			if (reg & HSSPI_PINGPONG_STATUS_SRC_BUSY)
251				cpu_relax();
252			else
253				break;
254		}
255		if (reg & HSSPI_PINGPONG_STATUS_SRC_BUSY)
256			rc = 1;
257	}
258
259	if (rc)
260		dev_err(&bs->pdev->dev, "transfer timed out!\n");
261
262	return rc;
263}
264
265static bool bcm63xx_prepare_prepend_transfer(struct spi_controller *host,
266					  struct spi_message *msg,
267					  struct spi_transfer *t_prepend)
268{
269
270	struct bcm63xx_hsspi *bs = spi_controller_get_devdata(host);
271	bool tx_only = false;
272	struct spi_transfer *t;
273
274	/*
275	 * Multiple transfers within a message may be combined into one transfer
276	 * to the controller using its prepend feature. A SPI message is prependable
277	 * only if the following are all true:
278	 *   1. One or more half duplex write transfer in single bit mode
279	 *   2. Optional full duplex read/write at the end
280	 *   3. No delay and cs_change between transfers
281	 */
282	bs->prepend_cnt = 0;
283	list_for_each_entry(t, &msg->transfers, transfer_list) {
284		if ((spi_delay_to_ns(&t->delay, t) > 0) || t->cs_change) {
285			bcm63xx_prepend_printk_on_checkfail(bs,
286				 "Delay or cs change not supported in prepend mode!\n");
287			return false;
288		}
289
290		tx_only = false;
291		if (t->tx_buf && !t->rx_buf) {
292			tx_only = true;
293			if (bs->prepend_cnt + t->len >
294				(HSSPI_BUFFER_LEN - HSSPI_OPCODE_LEN)) {
295				bcm63xx_prepend_printk_on_checkfail(bs,
296					 "exceed max buf len, abort prepending transfers!\n");
297				return false;
298			}
299
300			if (t->tx_nbits > SPI_NBITS_SINGLE &&
301				!list_is_last(&t->transfer_list, &msg->transfers)) {
302				bcm63xx_prepend_printk_on_checkfail(bs,
303					 "multi-bit prepend buf not supported!\n");
304				return false;
305			}
306
307			if (t->tx_nbits == SPI_NBITS_SINGLE) {
308				memcpy(bs->prepend_buf + bs->prepend_cnt, t->tx_buf, t->len);
309				bs->prepend_cnt += t->len;
310			}
311		} else {
312			if (!list_is_last(&t->transfer_list, &msg->transfers)) {
313				bcm63xx_prepend_printk_on_checkfail(bs,
314					 "rx/tx_rx transfer not supported when it is not last one!\n");
315				return false;
316			}
317		}
318
319		if (list_is_last(&t->transfer_list, &msg->transfers)) {
320			memcpy(t_prepend, t, sizeof(struct spi_transfer));
321
322			if (tx_only && t->tx_nbits == SPI_NBITS_SINGLE) {
323				/*
324				 * if the last one is also a single bit tx only transfer, merge
325				 * all of them into one single tx transfer
326				 */
327				t_prepend->len = bs->prepend_cnt;
328				t_prepend->tx_buf = bs->prepend_buf;
329				bs->prepend_cnt = 0;
330			} else {
331				/*
332				 * if the last one is not a tx only transfer or dual tx xfer, all
333				 * the previous transfers are sent through prepend bytes and
334				 * make sure it does not exceed the max prepend len
335				 */
336				if (bs->prepend_cnt > HSSPI_MAX_PREPEND_LEN) {
337					bcm63xx_prepend_printk_on_checkfail(bs,
338						"exceed max prepend len, abort prepending transfers!\n");
339					return false;
340				}
341			}
342		}
343	}
344
345	return true;
346}
347
348static int bcm63xx_hsspi_do_prepend_txrx(struct spi_device *spi,
349					 struct spi_transfer *t)
350{
351	struct bcm63xx_hsspi *bs = spi_controller_get_devdata(spi->controller);
352	unsigned int chip_select = spi_get_chipselect(spi, 0);
353	u16 opcode = 0, val;
354	const u8 *tx = t->tx_buf;
355	u8 *rx = t->rx_buf;
356	u32 reg = 0;
357
358	/*
359	 * shouldn't happen as we set the max_message_size in the probe.
360	 * but check it again in case some driver does not honor the max size
361	 */
362	if (t->len + bs->prepend_cnt > (HSSPI_BUFFER_LEN - HSSPI_OPCODE_LEN)) {
363		dev_warn(&bs->pdev->dev,
364			 "Prepend message large than fifo size len %d prepend %d\n",
365			 t->len, bs->prepend_cnt);
366		return -EINVAL;
367	}
368
369	bcm63xx_hsspi_set_clk(bs, spi, t->speed_hz);
370
371	if (tx && rx)
372		opcode = HSSPI_OP_READ_WRITE;
373	else if (tx)
374		opcode = HSSPI_OP_WRITE;
375	else if (rx)
376		opcode = HSSPI_OP_READ;
377
378	if ((opcode == HSSPI_OP_READ && t->rx_nbits == SPI_NBITS_DUAL) ||
379	    (opcode == HSSPI_OP_WRITE && t->tx_nbits == SPI_NBITS_DUAL)) {
380		opcode |= HSSPI_OP_MULTIBIT;
381
382		if (t->rx_nbits == SPI_NBITS_DUAL) {
383			reg |= 1 << MODE_CTRL_MULTIDATA_RD_SIZE_SHIFT;
384			reg |= bs->prepend_cnt << MODE_CTRL_MULTIDATA_RD_STRT_SHIFT;
385		}
386		if (t->tx_nbits == SPI_NBITS_DUAL) {
387			reg |= 1 << MODE_CTRL_MULTIDATA_WR_SIZE_SHIFT;
388			reg |= bs->prepend_cnt << MODE_CTRL_MULTIDATA_WR_STRT_SHIFT;
389		}
390	}
391
392	reg |= bs->prepend_cnt << MODE_CTRL_PREPENDBYTE_CNT_SHIFT;
393	__raw_writel(reg | 0xff,
394		     bs->regs + HSSPI_PROFILE_MODE_CTRL_REG(chip_select));
395
396	reinit_completion(&bs->done);
397	if (bs->prepend_cnt)
398		memcpy_toio(bs->fifo + HSSPI_OPCODE_LEN, bs->prepend_buf,
399			    bs->prepend_cnt);
400	if (tx)
401		memcpy_toio(bs->fifo + HSSPI_OPCODE_LEN + bs->prepend_cnt, tx,
402			    t->len);
403
404	*(__be16 *)(&val) = cpu_to_be16(opcode | t->len);
405	__raw_writew(val, bs->fifo);
406	/* enable interrupt */
407	if (bs->wait_mode == HSSPI_WAIT_MODE_INTR)
408		__raw_writel(HSSPI_PINGx_CMD_DONE(0), bs->regs + HSSPI_INT_MASK_REG);
409
410	/* start the transfer */
411	reg = chip_select << PINGPONG_CMD_SS_SHIFT |
412	    chip_select << PINGPONG_CMD_PROFILE_SHIFT |
413	    PINGPONG_COMMAND_START_NOW;
414	__raw_writel(reg, bs->regs + HSSPI_PINGPONG_COMMAND_REG(0));
415
416	if (bcm63xx_hsspi_wait_cmd(bs))
417		return -ETIMEDOUT;
418
419	if (rx)
420		memcpy_fromio(rx, bs->fifo, t->len);
421
422	return 0;
423}
424
425static void bcm63xx_hsspi_set_cs(struct bcm63xx_hsspi *bs, unsigned int cs,
426				 bool active)
427{
428	u32 reg;
429
430	mutex_lock(&bs->bus_mutex);
431	reg = __raw_readl(bs->regs + HSSPI_GLOBAL_CTRL_REG);
432
433	reg &= ~BIT(cs);
434	if (active == !(bs->cs_polarity & BIT(cs)))
435		reg |= BIT(cs);
436
437	__raw_writel(reg, bs->regs + HSSPI_GLOBAL_CTRL_REG);
438	mutex_unlock(&bs->bus_mutex);
439}
440
441static void bcm63xx_hsspi_set_clk(struct bcm63xx_hsspi *bs,
442				  struct spi_device *spi, int hz)
443{
444	unsigned int profile = spi_get_chipselect(spi, 0);
445	u32 reg;
446
447	reg = DIV_ROUND_UP(2048, DIV_ROUND_UP(bs->speed_hz, hz));
448	__raw_writel(CLK_CTRL_ACCUM_RST_ON_LOOP | reg,
449		     bs->regs + HSSPI_PROFILE_CLK_CTRL_REG(profile));
450
451	reg = __raw_readl(bs->regs + HSSPI_PROFILE_SIGNAL_CTRL_REG(profile));
452	if (hz > HSSPI_MAX_SYNC_CLOCK)
453		reg |= SIGNAL_CTRL_ASYNC_INPUT_PATH;
454	else
455		reg &= ~SIGNAL_CTRL_ASYNC_INPUT_PATH;
456	__raw_writel(reg, bs->regs + HSSPI_PROFILE_SIGNAL_CTRL_REG(profile));
457
458	mutex_lock(&bs->bus_mutex);
459	/* setup clock polarity */
460	reg = __raw_readl(bs->regs + HSSPI_GLOBAL_CTRL_REG);
461	reg &= ~GLOBAL_CTRL_CLK_POLARITY;
462	if (spi->mode & SPI_CPOL)
463		reg |= GLOBAL_CTRL_CLK_POLARITY;
464	__raw_writel(reg, bs->regs + HSSPI_GLOBAL_CTRL_REG);
465	mutex_unlock(&bs->bus_mutex);
466}
467
468static int bcm63xx_hsspi_do_txrx(struct spi_device *spi, struct spi_transfer *t)
469{
470	struct bcm63xx_hsspi *bs = spi_controller_get_devdata(spi->controller);
471	unsigned int chip_select = spi_get_chipselect(spi, 0);
472	u16 opcode = 0, val;
473	int pending = t->len;
474	int step_size = HSSPI_BUFFER_LEN;
475	const u8 *tx = t->tx_buf;
476	u8 *rx = t->rx_buf;
477	u32 reg = 0;
478
479	bcm63xx_hsspi_set_clk(bs, spi, t->speed_hz);
480	if (!t->cs_off)
481		bcm63xx_hsspi_set_cs(bs, spi_get_chipselect(spi, 0), true);
482
483	if (tx && rx)
484		opcode = HSSPI_OP_READ_WRITE;
485	else if (tx)
486		opcode = HSSPI_OP_WRITE;
487	else if (rx)
488		opcode = HSSPI_OP_READ;
489
490	if (opcode != HSSPI_OP_READ)
491		step_size -= HSSPI_OPCODE_LEN;
492
493	if ((opcode == HSSPI_OP_READ && t->rx_nbits == SPI_NBITS_DUAL) ||
494	    (opcode == HSSPI_OP_WRITE && t->tx_nbits == SPI_NBITS_DUAL)) {
495		opcode |= HSSPI_OP_MULTIBIT;
496
497		if (t->rx_nbits == SPI_NBITS_DUAL)
498			reg |= 1 << MODE_CTRL_MULTIDATA_RD_SIZE_SHIFT;
499		if (t->tx_nbits == SPI_NBITS_DUAL)
500			reg |= 1 << MODE_CTRL_MULTIDATA_WR_SIZE_SHIFT;
501	}
502
503	__raw_writel(reg | 0xff,
504		     bs->regs + HSSPI_PROFILE_MODE_CTRL_REG(chip_select));
505
506	while (pending > 0) {
507		int curr_step = min_t(int, step_size, pending);
508
509		reinit_completion(&bs->done);
510		if (tx) {
511			memcpy_toio(bs->fifo + HSSPI_OPCODE_LEN, tx, curr_step);
512			tx += curr_step;
513		}
514
515		*(__be16 *)(&val) = cpu_to_be16(opcode | curr_step);
516		__raw_writew(val, bs->fifo);
517
518		/* enable interrupt */
519		if (bs->wait_mode == HSSPI_WAIT_MODE_INTR)
520			__raw_writel(HSSPI_PINGx_CMD_DONE(0),
521				     bs->regs + HSSPI_INT_MASK_REG);
522
523		reg =  !chip_select << PINGPONG_CMD_SS_SHIFT |
524			    chip_select << PINGPONG_CMD_PROFILE_SHIFT |
525			    PINGPONG_COMMAND_START_NOW;
526		__raw_writel(reg, bs->regs + HSSPI_PINGPONG_COMMAND_REG(0));
527
528		if (bcm63xx_hsspi_wait_cmd(bs))
 
529			return -ETIMEDOUT;
 
530
531		if (rx) {
532			memcpy_fromio(rx, bs->fifo, curr_step);
533			rx += curr_step;
534		}
535
536		pending -= curr_step;
537	}
538
539	return 0;
540}
541
542static int bcm63xx_hsspi_setup(struct spi_device *spi)
543{
544	struct bcm63xx_hsspi *bs = spi_controller_get_devdata(spi->controller);
545	u32 reg;
546
547	reg = __raw_readl(bs->regs +
548			  HSSPI_PROFILE_SIGNAL_CTRL_REG(spi_get_chipselect(spi, 0)));
549	reg &= ~(SIGNAL_CTRL_LAUNCH_RISING | SIGNAL_CTRL_LATCH_RISING);
550	if (spi->mode & SPI_CPHA)
551		reg |= SIGNAL_CTRL_LAUNCH_RISING;
552	else
553		reg |= SIGNAL_CTRL_LATCH_RISING;
554	__raw_writel(reg, bs->regs +
555		     HSSPI_PROFILE_SIGNAL_CTRL_REG(spi_get_chipselect(spi, 0)));
556
557	mutex_lock(&bs->bus_mutex);
558	reg = __raw_readl(bs->regs + HSSPI_GLOBAL_CTRL_REG);
559
560	/* only change actual polarities if there is no transfer */
561	if ((reg & GLOBAL_CTRL_CS_POLARITY_MASK) == bs->cs_polarity) {
562		if (spi->mode & SPI_CS_HIGH)
563			reg |= BIT(spi_get_chipselect(spi, 0));
564		else
565			reg &= ~BIT(spi_get_chipselect(spi, 0));
566		__raw_writel(reg, bs->regs + HSSPI_GLOBAL_CTRL_REG);
567	}
568
569	if (spi->mode & SPI_CS_HIGH)
570		bs->cs_polarity |= BIT(spi_get_chipselect(spi, 0));
571	else
572		bs->cs_polarity &= ~BIT(spi_get_chipselect(spi, 0));
573
574	mutex_unlock(&bs->bus_mutex);
575
576	return 0;
577}
578
579static int bcm63xx_hsspi_do_dummy_cs_txrx(struct spi_device *spi,
580				      struct spi_message *msg)
581{
582	struct bcm63xx_hsspi *bs = spi_controller_get_devdata(spi->controller);
 
 
583	int status = -EINVAL;
584	int dummy_cs;
585	bool keep_cs = false;
586	struct spi_transfer *t;
587
588	/*
589	 * This controller does not support keeping CS active during idle.
590	 * To work around this, we use the following ugly hack:
591	 *
592	 * a. Invert the target chip select's polarity so it will be active.
593	 * b. Select a "dummy" chip select to use as the hardware target.
594	 * c. Invert the dummy chip select's polarity so it will be inactive
595	 *    during the actual transfers.
596	 * d. Tell the hardware to send to the dummy chip select. Thanks to
597	 *    the multiplexed nature of SPI the actual target will receive
598	 *    the transfer and we see its response.
599	 *
600	 * e. At the end restore the polarities again to their default values.
601	 */
602
603	dummy_cs = !spi_get_chipselect(spi, 0);
604	bcm63xx_hsspi_set_cs(bs, dummy_cs, true);
605
606	list_for_each_entry(t, &msg->transfers, transfer_list) {
607		/*
608		 * We are here because one of reasons below:
609		 * a. Message is not prependable and in default auto xfer mode. This mean
610		 *    we fallback to dummy cs mode at maximum 25MHz safe clock rate.
611		 * b. User set to use the dummy cs mode.
612		 */
613		if (bs->xfer_mode == HSSPI_XFER_MODE_AUTO) {
614			if (t->speed_hz > HSSPI_MAX_SYNC_CLOCK) {
615				t->speed_hz = HSSPI_MAX_SYNC_CLOCK;
616				dev_warn_once(&bs->pdev->dev,
617					"Force to dummy cs mode. Reduce the speed to %dHz",
618					t->speed_hz);
619			}
620		}
621
622		status = bcm63xx_hsspi_do_txrx(spi, t);
623		if (status)
624			break;
625
626		msg->actual_length += t->len;
627
628		spi_transfer_delay_exec(t);
629
630		/* use existing cs change logic from spi_transfer_one_message */
631		if (t->cs_change) {
632			if (list_is_last(&t->transfer_list, &msg->transfers)) {
633				keep_cs = true;
634			} else {
635				if (!t->cs_off)
636					bcm63xx_hsspi_set_cs(bs, spi_get_chipselect(spi, 0), false);
637
638				spi_transfer_cs_change_delay_exec(msg, t);
639
640				if (!list_next_entry(t, transfer_list)->cs_off)
641					bcm63xx_hsspi_set_cs(bs, spi_get_chipselect(spi, 0), true);
642			}
643		} else if (!list_is_last(&t->transfer_list, &msg->transfers) &&
644			   t->cs_off != list_next_entry(t, transfer_list)->cs_off) {
645			bcm63xx_hsspi_set_cs(bs, spi_get_chipselect(spi, 0), t->cs_off);
646		}
647	}
648
649	bcm63xx_hsspi_set_cs(bs, dummy_cs, false);
650	if (status || !keep_cs)
651		bcm63xx_hsspi_set_cs(bs, spi_get_chipselect(spi, 0), false);
652
653	return status;
654}
655
656static int bcm63xx_hsspi_transfer_one(struct spi_controller *host,
657				      struct spi_message *msg)
658{
659	struct bcm63xx_hsspi *bs = spi_controller_get_devdata(host);
660	struct spi_device *spi = msg->spi;
661	int status = -EINVAL;
662	bool prependable = false;
663	struct spi_transfer t_prepend;
664
665	mutex_lock(&bs->msg_mutex);
666
667	if (bs->xfer_mode != HSSPI_XFER_MODE_DUMMYCS)
668		prependable = bcm63xx_prepare_prepend_transfer(host, msg, &t_prepend);
669
670	if (prependable) {
671		status = bcm63xx_hsspi_do_prepend_txrx(spi, &t_prepend);
672		msg->actual_length = (t_prepend.len + bs->prepend_cnt);
673	} else {
674		if (bs->xfer_mode == HSSPI_XFER_MODE_PREPEND) {
675			dev_err(&bs->pdev->dev,
676				"User sets prepend mode but msg not prependable! Abort transfer\n");
677			status = -EINVAL;
678		} else
679			status = bcm63xx_hsspi_do_dummy_cs_txrx(spi, msg);
680	}
681
682	mutex_unlock(&bs->msg_mutex);
683	msg->status = status;
684	spi_finalize_current_message(host);
685
686	return 0;
687}
688
689static bool bcm63xx_hsspi_mem_supports_op(struct spi_mem *mem,
690			    const struct spi_mem_op *op)
691{
692	if (!spi_mem_default_supports_op(mem, op))
693		return false;
694
695	/* Controller doesn't support spi mem dual io mode */
696	if ((op->cmd.opcode == SPINOR_OP_READ_1_2_2) ||
697		(op->cmd.opcode == SPINOR_OP_READ_1_2_2_4B) ||
698		(op->cmd.opcode == SPINOR_OP_READ_1_2_2_DTR) ||
699		(op->cmd.opcode == SPINOR_OP_READ_1_2_2_DTR_4B))
700		return false;
701
702	return true;
703}
704
705static const struct spi_controller_mem_ops bcm63xx_hsspi_mem_ops = {
706	.supports_op = bcm63xx_hsspi_mem_supports_op,
707};
708
709static irqreturn_t bcm63xx_hsspi_interrupt(int irq, void *dev_id)
710{
711	struct bcm63xx_hsspi *bs = (struct bcm63xx_hsspi *)dev_id;
712
713	if (__raw_readl(bs->regs + HSSPI_INT_STATUS_MASKED_REG) == 0)
714		return IRQ_NONE;
715
716	__raw_writel(HSSPI_INT_CLEAR_ALL, bs->regs + HSSPI_INT_STATUS_REG);
717	__raw_writel(0, bs->regs + HSSPI_INT_MASK_REG);
718
719	complete(&bs->done);
720
721	return IRQ_HANDLED;
722}
723
724static int bcm63xx_hsspi_probe(struct platform_device *pdev)
725{
726	struct spi_controller *host;
727	struct bcm63xx_hsspi *bs;
728	void __iomem *regs;
729	struct device *dev = &pdev->dev;
730	struct clk *clk, *pll_clk = NULL;
731	int irq, ret;
732	u32 reg, rate, num_cs = HSSPI_SPI_MAX_CS;
733	struct reset_control *reset;
734
735	irq = platform_get_irq(pdev, 0);
736	if (irq < 0)
737		return irq;
738
739	regs = devm_platform_ioremap_resource(pdev, 0);
740	if (IS_ERR(regs))
741		return PTR_ERR(regs);
742
743	clk = devm_clk_get(dev, "hsspi");
744
745	if (IS_ERR(clk))
746		return PTR_ERR(clk);
747
748	reset = devm_reset_control_get_optional_exclusive(dev, NULL);
749	if (IS_ERR(reset))
750		return PTR_ERR(reset);
751
752	ret = clk_prepare_enable(clk);
753	if (ret)
754		return ret;
755
756	ret = reset_control_reset(reset);
757	if (ret) {
758		dev_err(dev, "unable to reset device: %d\n", ret);
759		goto out_disable_clk;
760	}
761
762	rate = clk_get_rate(clk);
763	if (!rate) {
764		pll_clk = devm_clk_get(dev, "pll");
765
766		if (IS_ERR(pll_clk)) {
767			ret = PTR_ERR(pll_clk);
768			goto out_disable_clk;
769		}
770
771		ret = clk_prepare_enable(pll_clk);
772		if (ret)
773			goto out_disable_clk;
774
775		rate = clk_get_rate(pll_clk);
776		if (!rate) {
777			ret = -EINVAL;
778			goto out_disable_pll_clk;
779		}
780	}
781
782	host = spi_alloc_host(&pdev->dev, sizeof(*bs));
783	if (!host) {
784		ret = -ENOMEM;
785		goto out_disable_pll_clk;
786	}
787
788	bs = spi_controller_get_devdata(host);
789	bs->pdev = pdev;
790	bs->clk = clk;
791	bs->pll_clk = pll_clk;
792	bs->regs = regs;
793	bs->speed_hz = rate;
794	bs->fifo = (u8 __iomem *)(bs->regs + HSSPI_FIFO_REG(0));
795	bs->wait_mode = HSSPI_WAIT_MODE_POLLING;
796	bs->prepend_buf = devm_kzalloc(dev, HSSPI_BUFFER_LEN, GFP_KERNEL);
797	if (!bs->prepend_buf) {
798		ret = -ENOMEM;
799		goto out_put_host;
800	}
801
802	mutex_init(&bs->bus_mutex);
803	mutex_init(&bs->msg_mutex);
804	init_completion(&bs->done);
805
806	host->mem_ops = &bcm63xx_hsspi_mem_ops;
807	host->dev.of_node = dev->of_node;
808	if (!dev->of_node)
809		host->bus_num = HSSPI_BUS_NUM;
810
811	of_property_read_u32(dev->of_node, "num-cs", &num_cs);
812	if (num_cs > 8) {
813		dev_warn(dev, "unsupported number of cs (%i), reducing to 8\n",
814			 num_cs);
815		num_cs = HSSPI_SPI_MAX_CS;
816	}
817	host->num_chipselect = num_cs;
818	host->setup = bcm63xx_hsspi_setup;
819	host->transfer_one_message = bcm63xx_hsspi_transfer_one;
820	host->max_transfer_size = bcm63xx_hsspi_max_message_size;
821	host->max_message_size = bcm63xx_hsspi_max_message_size;
822
823	host->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH |
824			    SPI_RX_DUAL | SPI_TX_DUAL;
825	host->bits_per_word_mask = SPI_BPW_MASK(8);
826	host->auto_runtime_pm = true;
827
828	platform_set_drvdata(pdev, host);
829
830	/* Initialize the hardware */
831	__raw_writel(0, bs->regs + HSSPI_INT_MASK_REG);
832
833	/* clean up any pending interrupts */
834	__raw_writel(HSSPI_INT_CLEAR_ALL, bs->regs + HSSPI_INT_STATUS_REG);
835
836	/* read out default CS polarities */
837	reg = __raw_readl(bs->regs + HSSPI_GLOBAL_CTRL_REG);
838	bs->cs_polarity = reg & GLOBAL_CTRL_CS_POLARITY_MASK;
839	__raw_writel(reg | GLOBAL_CTRL_CLK_GATE_SSOFF,
840		     bs->regs + HSSPI_GLOBAL_CTRL_REG);
841
842	if (irq > 0) {
843		ret = devm_request_irq(dev, irq, bcm63xx_hsspi_interrupt, IRQF_SHARED,
844				       pdev->name, bs);
845
846		if (ret)
847			goto out_put_host;
848	}
849
850	pm_runtime_enable(&pdev->dev);
851
852	ret = sysfs_create_group(&pdev->dev.kobj, &bcm63xx_hsspi_group);
853	if (ret) {
854		dev_err(&pdev->dev, "couldn't register sysfs group\n");
855		goto out_pm_disable;
856	}
857
858	/* register and we are done */
859	ret = devm_spi_register_controller(dev, host);
860	if (ret)
861		goto out_sysgroup_disable;
862
863	dev_info(dev, "Broadcom 63XX High Speed SPI Controller driver");
864
865	return 0;
866
867out_sysgroup_disable:
868	sysfs_remove_group(&pdev->dev.kobj, &bcm63xx_hsspi_group);
869out_pm_disable:
870	pm_runtime_disable(&pdev->dev);
871out_put_host:
872	spi_controller_put(host);
873out_disable_pll_clk:
874	clk_disable_unprepare(pll_clk);
875out_disable_clk:
876	clk_disable_unprepare(clk);
877	return ret;
878}
879
880
881static void bcm63xx_hsspi_remove(struct platform_device *pdev)
882{
883	struct spi_controller *host = platform_get_drvdata(pdev);
884	struct bcm63xx_hsspi *bs = spi_controller_get_devdata(host);
885
886	/* reset the hardware and block queue progress */
887	__raw_writel(0, bs->regs + HSSPI_INT_MASK_REG);
888	clk_disable_unprepare(bs->pll_clk);
889	clk_disable_unprepare(bs->clk);
890	sysfs_remove_group(&pdev->dev.kobj, &bcm63xx_hsspi_group);
 
891}
892
893#ifdef CONFIG_PM_SLEEP
894static int bcm63xx_hsspi_suspend(struct device *dev)
895{
896	struct spi_controller *host = dev_get_drvdata(dev);
897	struct bcm63xx_hsspi *bs = spi_controller_get_devdata(host);
898
899	spi_controller_suspend(host);
900	clk_disable_unprepare(bs->pll_clk);
901	clk_disable_unprepare(bs->clk);
902
903	return 0;
904}
905
906static int bcm63xx_hsspi_resume(struct device *dev)
907{
908	struct spi_controller *host = dev_get_drvdata(dev);
909	struct bcm63xx_hsspi *bs = spi_controller_get_devdata(host);
910	int ret;
911
912	ret = clk_prepare_enable(bs->clk);
913	if (ret)
914		return ret;
915
916	if (bs->pll_clk) {
917		ret = clk_prepare_enable(bs->pll_clk);
918		if (ret) {
919			clk_disable_unprepare(bs->clk);
920			return ret;
921		}
922	}
923
924	spi_controller_resume(host);
925
926	return 0;
927}
928#endif
929
930static SIMPLE_DEV_PM_OPS(bcm63xx_hsspi_pm_ops, bcm63xx_hsspi_suspend,
931			 bcm63xx_hsspi_resume);
932
933static const struct of_device_id bcm63xx_hsspi_of_match[] = {
934	{ .compatible = "brcm,bcm6328-hsspi", },
935	{ .compatible = "brcm,bcmbca-hsspi-v1.0", },
936	{ },
937};
938MODULE_DEVICE_TABLE(of, bcm63xx_hsspi_of_match);
939
940static struct platform_driver bcm63xx_hsspi_driver = {
941	.driver = {
942		.name	= "bcm63xx-hsspi",
943		.pm	= &bcm63xx_hsspi_pm_ops,
944		.of_match_table = bcm63xx_hsspi_of_match,
945	},
946	.probe		= bcm63xx_hsspi_probe,
947	.remove_new	= bcm63xx_hsspi_remove,
948};
949
950module_platform_driver(bcm63xx_hsspi_driver);
951
952MODULE_ALIAS("platform:bcm63xx_hsspi");
953MODULE_DESCRIPTION("Broadcom BCM63xx High Speed SPI Controller driver");
954MODULE_AUTHOR("Jonas Gorski <jogo@openwrt.org>");
955MODULE_LICENSE("GPL");