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v6.8
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
 
 
 
  3 *
  4 *  Copyright (C) 2012 Thomas Langer <thomas.langer@lantiq.com>
  5 */
  6
  7#include <linux/module.h>
  8#include <linux/device.h>
  9#include <linux/platform_device.h>
 10#include <linux/spi/spi.h>
 11#include <linux/delay.h>
 
 12#include <linux/of.h>
 13#include <linux/of_platform.h>
 14
 15#include <lantiq_soc.h>
 16
 17#define DRV_NAME		"sflash-falcon"
 18
 19#define FALCON_SPI_XFER_BEGIN	(1 << 0)
 20#define FALCON_SPI_XFER_END	(1 << 1)
 21
 22/* Bus Read Configuration Register0 */
 23#define BUSRCON0		0x00000010
 24/* Bus Write Configuration Register0 */
 25#define BUSWCON0		0x00000018
 26/* Serial Flash Configuration Register */
 27#define SFCON			0x00000080
 28/* Serial Flash Time Register */
 29#define SFTIME			0x00000084
 30/* Serial Flash Status Register */
 31#define SFSTAT			0x00000088
 32/* Serial Flash Command Register */
 33#define SFCMD			0x0000008C
 34/* Serial Flash Address Register */
 35#define SFADDR			0x00000090
 36/* Serial Flash Data Register */
 37#define SFDATA			0x00000094
 38/* Serial Flash I/O Control Register */
 39#define SFIO			0x00000098
 40/* EBU Clock Control Register */
 41#define EBUCC			0x000000C4
 42
 43/* Dummy Phase Length */
 44#define SFCMD_DUMLEN_OFFSET	16
 45#define SFCMD_DUMLEN_MASK	0x000F0000
 46/* Chip Select */
 47#define SFCMD_CS_OFFSET		24
 48#define SFCMD_CS_MASK		0x07000000
 49/* field offset */
 50#define SFCMD_ALEN_OFFSET	20
 51#define SFCMD_ALEN_MASK		0x00700000
 52/* SCK Rise-edge Position */
 53#define SFTIME_SCKR_POS_OFFSET	8
 54#define SFTIME_SCKR_POS_MASK	0x00000F00
 55/* SCK Period */
 56#define SFTIME_SCK_PER_OFFSET	0
 57#define SFTIME_SCK_PER_MASK	0x0000000F
 58/* SCK Fall-edge Position */
 59#define SFTIME_SCKF_POS_OFFSET	12
 60#define SFTIME_SCKF_POS_MASK	0x0000F000
 61/* Device Size */
 62#define SFCON_DEV_SIZE_A23_0	0x03000000
 63#define SFCON_DEV_SIZE_MASK	0x0F000000
 64/* Read Data Position */
 65#define SFTIME_RD_POS_MASK	0x000F0000
 66/* Data Output */
 67#define SFIO_UNUSED_WD_MASK	0x0000000F
 68/* Command Opcode mask */
 69#define SFCMD_OPC_MASK		0x000000FF
 70/* dlen bytes of data to write */
 71#define SFCMD_DIR_WRITE		0x00000100
 72/* Data Length offset */
 73#define SFCMD_DLEN_OFFSET	9
 74/* Command Error */
 75#define SFSTAT_CMD_ERR		0x20000000
 76/* Access Command Pending */
 77#define SFSTAT_CMD_PEND		0x00400000
 78/* Frequency set to 100MHz. */
 79#define EBUCC_EBUDIV_SELF100	0x00000001
 80/* Serial Flash */
 81#define BUSRCON0_AGEN_SERIAL_FLASH	0xF0000000
 82/* 8-bit multiplexed */
 83#define BUSRCON0_PORTW_8_BIT_MUX	0x00000000
 84/* Serial Flash */
 85#define BUSWCON0_AGEN_SERIAL_FLASH	0xF0000000
 86/* Chip Select after opcode */
 87#define SFCMD_KEEP_CS_KEEP_SELECTED	0x00008000
 88
 89#define CLOCK_100M	100000000
 90#define CLOCK_50M	50000000
 91
 92struct falcon_sflash {
 93	u32 sfcmd; /* for caching of opcode, direction, ... */
 94	struct spi_controller *host;
 95};
 96
 97int falcon_sflash_xfer(struct spi_device *spi, struct spi_transfer *t,
 98		unsigned long flags)
 99{
100	struct device *dev = &spi->dev;
101	struct falcon_sflash *priv = spi_controller_get_devdata(spi->controller);
102	const u8 *txp = t->tx_buf;
103	u8 *rxp = t->rx_buf;
104	unsigned int bytelen = ((8 * t->len + 7) / 8);
105	unsigned int len, alen, dumlen;
106	u32 val;
107	enum {
108		state_init,
109		state_command_prepare,
110		state_write,
111		state_read,
112		state_disable_cs,
113		state_end
114	} state = state_init;
115
116	do {
117		switch (state) {
118		case state_init: /* detect phase of upper layer sequence */
119		{
120			/* initial write ? */
121			if (flags & FALCON_SPI_XFER_BEGIN) {
122				if (!txp) {
123					dev_err(dev,
124						"BEGIN without tx data!\n");
125					return -ENODATA;
126				}
127				/*
128				 * Prepare the parts of the sfcmd register,
129				 * which should not change during a sequence!
130				 * Only exception are the length fields,
131				 * especially alen and dumlen.
132				 */
133
134				priv->sfcmd = ((spi_get_chipselect(spi, 0)
135						<< SFCMD_CS_OFFSET)
136					       & SFCMD_CS_MASK);
137				priv->sfcmd |= SFCMD_KEEP_CS_KEEP_SELECTED;
138				priv->sfcmd |= *txp;
139				txp++;
140				bytelen--;
141				if (bytelen) {
142					/*
143					 * more data:
144					 * maybe address and/or dummy
145					 */
146					state = state_command_prepare;
147					break;
148				} else {
149					dev_dbg(dev, "write cmd %02X\n",
150						priv->sfcmd & SFCMD_OPC_MASK);
151				}
152			}
153			/* continued write ? */
154			if (txp && bytelen) {
155				state = state_write;
156				break;
157			}
158			/* read data? */
159			if (rxp && bytelen) {
160				state = state_read;
161				break;
162			}
163			/* end of sequence? */
164			if (flags & FALCON_SPI_XFER_END)
165				state = state_disable_cs;
166			else
167				state = state_end;
168			break;
169		}
170		/* collect tx data for address and dummy phase */
171		case state_command_prepare:
172		{
173			/* txp is valid, already checked */
174			val = 0;
175			alen = 0;
176			dumlen = 0;
177			while (bytelen > 0) {
178				if (alen < 3) {
179					val = (val << 8) | (*txp++);
180					alen++;
181				} else if ((dumlen < 15) && (*txp == 0)) {
182					/*
183					 * assume dummy bytes are set to 0
184					 * from upper layer
185					 */
186					dumlen++;
187					txp++;
188				} else {
189					break;
190				}
191				bytelen--;
192			}
193			priv->sfcmd &= ~(SFCMD_ALEN_MASK | SFCMD_DUMLEN_MASK);
194			priv->sfcmd |= (alen << SFCMD_ALEN_OFFSET) |
195					 (dumlen << SFCMD_DUMLEN_OFFSET);
196			if (alen > 0)
197				ltq_ebu_w32(val, SFADDR);
198
199			dev_dbg(dev, "wr %02X, alen=%d (addr=%06X) dlen=%d\n",
200				priv->sfcmd & SFCMD_OPC_MASK,
201				alen, val, dumlen);
202
203			if (bytelen > 0) {
204				/* continue with write */
205				state = state_write;
206			} else if (flags & FALCON_SPI_XFER_END) {
207				/* end of sequence? */
208				state = state_disable_cs;
209			} else {
210				/*
211				 * go to end and expect another
212				 * call (read or write)
213				 */
214				state = state_end;
215			}
216			break;
217		}
218		case state_write:
219		{
220			/* txp still valid */
221			priv->sfcmd |= SFCMD_DIR_WRITE;
222			len = 0;
223			val = 0;
224			do {
225				if (bytelen--)
226					val |= (*txp++) << (8 * len++);
227				if ((flags & FALCON_SPI_XFER_END)
228				    && (bytelen == 0)) {
229					priv->sfcmd &=
230						~SFCMD_KEEP_CS_KEEP_SELECTED;
231				}
232				if ((len == 4) || (bytelen == 0)) {
233					ltq_ebu_w32(val, SFDATA);
234					ltq_ebu_w32(priv->sfcmd
235						| (len<<SFCMD_DLEN_OFFSET),
236						SFCMD);
237					len = 0;
238					val = 0;
239					priv->sfcmd &= ~(SFCMD_ALEN_MASK
240							 | SFCMD_DUMLEN_MASK);
241				}
242			} while (bytelen);
243			state = state_end;
244			break;
245		}
246		case state_read:
247		{
248			/* read data */
249			priv->sfcmd &= ~SFCMD_DIR_WRITE;
250			do {
251				if ((flags & FALCON_SPI_XFER_END)
252				    && (bytelen <= 4)) {
253					priv->sfcmd &=
254						~SFCMD_KEEP_CS_KEEP_SELECTED;
255				}
256				len = (bytelen > 4) ? 4 : bytelen;
257				bytelen -= len;
258				ltq_ebu_w32(priv->sfcmd
259					| (len << SFCMD_DLEN_OFFSET), SFCMD);
260				priv->sfcmd &= ~(SFCMD_ALEN_MASK
261						 | SFCMD_DUMLEN_MASK);
262				do {
263					val = ltq_ebu_r32(SFSTAT);
264					if (val & SFSTAT_CMD_ERR) {
265						/* reset error status */
266						dev_err(dev, "SFSTAT: CMD_ERR");
267						dev_err(dev, " (%x)\n", val);
268						ltq_ebu_w32(SFSTAT_CMD_ERR,
269							SFSTAT);
270						return -EBADE;
271					}
272				} while (val & SFSTAT_CMD_PEND);
273				val = ltq_ebu_r32(SFDATA);
274				do {
275					*rxp = (val & 0xFF);
276					rxp++;
277					val >>= 8;
278					len--;
279				} while (len);
280			} while (bytelen);
281			state = state_end;
282			break;
283		}
284		case state_disable_cs:
285		{
286			priv->sfcmd &= ~SFCMD_KEEP_CS_KEEP_SELECTED;
287			ltq_ebu_w32(priv->sfcmd | (0 << SFCMD_DLEN_OFFSET),
288				SFCMD);
289			val = ltq_ebu_r32(SFSTAT);
290			if (val & SFSTAT_CMD_ERR) {
291				/* reset error status */
292				dev_err(dev, "SFSTAT: CMD_ERR (%x)\n", val);
293				ltq_ebu_w32(SFSTAT_CMD_ERR, SFSTAT);
294				return -EBADE;
295			}
296			state = state_end;
297			break;
298		}
299		case state_end:
300			break;
301		}
302	} while (state != state_end);
303
304	return 0;
305}
306
307static int falcon_sflash_setup(struct spi_device *spi)
308{
309	unsigned int i;
310	unsigned long flags;
311
312	spin_lock_irqsave(&ebu_lock, flags);
313
314	if (spi->max_speed_hz >= CLOCK_100M) {
315		/* set EBU clock to 100 MHz */
316		ltq_sys1_w32_mask(0, EBUCC_EBUDIV_SELF100, EBUCC);
317		i = 1; /* divider */
318	} else {
319		/* set EBU clock to 50 MHz */
320		ltq_sys1_w32_mask(EBUCC_EBUDIV_SELF100, 0, EBUCC);
321
322		/* search for suitable divider */
323		for (i = 1; i < 7; i++) {
324			if (CLOCK_50M / i <= spi->max_speed_hz)
325				break;
326		}
327	}
328
329	/* setup period of serial clock */
330	ltq_ebu_w32_mask(SFTIME_SCKF_POS_MASK
331		     | SFTIME_SCKR_POS_MASK
332		     | SFTIME_SCK_PER_MASK,
333		     (i << SFTIME_SCKR_POS_OFFSET)
334		     | (i << (SFTIME_SCK_PER_OFFSET + 1)),
335		     SFTIME);
336
337	/*
338	 * set some bits of unused_wd, to not trigger HOLD/WP
339	 * signals on non QUAD flashes
340	 */
341	ltq_ebu_w32((SFIO_UNUSED_WD_MASK & (0x8 | 0x4)), SFIO);
342
343	ltq_ebu_w32(BUSRCON0_AGEN_SERIAL_FLASH | BUSRCON0_PORTW_8_BIT_MUX,
344			BUSRCON0);
345	ltq_ebu_w32(BUSWCON0_AGEN_SERIAL_FLASH, BUSWCON0);
346	/* set address wrap around to maximum for 24-bit addresses */
347	ltq_ebu_w32_mask(SFCON_DEV_SIZE_MASK, SFCON_DEV_SIZE_A23_0, SFCON);
348
349	spin_unlock_irqrestore(&ebu_lock, flags);
350
351	return 0;
352}
353
354static int falcon_sflash_xfer_one(struct spi_controller *host,
 
 
 
 
 
 
 
 
 
 
355					struct spi_message *m)
356{
357	struct falcon_sflash *priv = spi_controller_get_devdata(host);
358	struct spi_transfer *t;
359	unsigned long spi_flags;
360	unsigned long flags;
361	int ret = 0;
362
363	priv->sfcmd = 0;
364	m->actual_length = 0;
365
366	spi_flags = FALCON_SPI_XFER_BEGIN;
367	list_for_each_entry(t, &m->transfers, transfer_list) {
368		if (list_is_last(&t->transfer_list, &m->transfers))
369			spi_flags |= FALCON_SPI_XFER_END;
370
371		spin_lock_irqsave(&ebu_lock, flags);
372		ret = falcon_sflash_xfer(m->spi, t, spi_flags);
373		spin_unlock_irqrestore(&ebu_lock, flags);
374
375		if (ret)
376			break;
377
378		m->actual_length += t->len;
379
380		WARN_ON(t->delay.value || t->cs_change);
381		spi_flags = 0;
382	}
383
384	m->status = ret;
385	spi_finalize_current_message(host);
386
387	return 0;
388}
389
390static int falcon_sflash_probe(struct platform_device *pdev)
391{
392	struct falcon_sflash *priv;
393	struct spi_controller *host;
394	int ret;
395
396	host = spi_alloc_host(&pdev->dev, sizeof(*priv));
397	if (!host)
 
 
 
 
 
398		return -ENOMEM;
399
400	priv = spi_controller_get_devdata(host);
401	priv->host = host;
 
 
 
 
 
 
 
 
402
403	host->mode_bits = SPI_MODE_3;
404	host->flags = SPI_CONTROLLER_HALF_DUPLEX;
405	host->setup = falcon_sflash_setup;
406	host->transfer_one_message = falcon_sflash_xfer_one;
407	host->dev.of_node = pdev->dev.of_node;
408
409	ret = devm_spi_register_controller(&pdev->dev, host);
410	if (ret)
411		spi_controller_put(host);
412	return ret;
413}
414
415static const struct of_device_id falcon_sflash_match[] = {
416	{ .compatible = "lantiq,sflash-falcon" },
417	{},
418};
419MODULE_DEVICE_TABLE(of, falcon_sflash_match);
420
421static struct platform_driver falcon_sflash_driver = {
422	.probe	= falcon_sflash_probe,
423	.driver = {
424		.name	= DRV_NAME,
 
425		.of_match_table = falcon_sflash_match,
426	}
427};
428
429module_platform_driver(falcon_sflash_driver);
430
431MODULE_LICENSE("GPL");
432MODULE_DESCRIPTION("Lantiq Falcon SPI/SFLASH controller driver");
v3.15
 
  1/*
  2 *  This program is free software; you can redistribute it and/or modify it
  3 *  under the terms of the GNU General Public License version 2 as published
  4 *  by the Free Software Foundation.
  5 *
  6 *  Copyright (C) 2012 Thomas Langer <thomas.langer@lantiq.com>
  7 */
  8
  9#include <linux/module.h>
 10#include <linux/device.h>
 11#include <linux/platform_device.h>
 12#include <linux/spi/spi.h>
 13#include <linux/delay.h>
 14#include <linux/workqueue.h>
 15#include <linux/of.h>
 16#include <linux/of_platform.h>
 17
 18#include <lantiq_soc.h>
 19
 20#define DRV_NAME		"sflash-falcon"
 21
 22#define FALCON_SPI_XFER_BEGIN	(1 << 0)
 23#define FALCON_SPI_XFER_END	(1 << 1)
 24
 25/* Bus Read Configuration Register0 */
 26#define BUSRCON0		0x00000010
 27/* Bus Write Configuration Register0 */
 28#define BUSWCON0		0x00000018
 29/* Serial Flash Configuration Register */
 30#define SFCON			0x00000080
 31/* Serial Flash Time Register */
 32#define SFTIME			0x00000084
 33/* Serial Flash Status Register */
 34#define SFSTAT			0x00000088
 35/* Serial Flash Command Register */
 36#define SFCMD			0x0000008C
 37/* Serial Flash Address Register */
 38#define SFADDR			0x00000090
 39/* Serial Flash Data Register */
 40#define SFDATA			0x00000094
 41/* Serial Flash I/O Control Register */
 42#define SFIO			0x00000098
 43/* EBU Clock Control Register */
 44#define EBUCC			0x000000C4
 45
 46/* Dummy Phase Length */
 47#define SFCMD_DUMLEN_OFFSET	16
 48#define SFCMD_DUMLEN_MASK	0x000F0000
 49/* Chip Select */
 50#define SFCMD_CS_OFFSET		24
 51#define SFCMD_CS_MASK		0x07000000
 52/* field offset */
 53#define SFCMD_ALEN_OFFSET	20
 54#define SFCMD_ALEN_MASK		0x00700000
 55/* SCK Rise-edge Position */
 56#define SFTIME_SCKR_POS_OFFSET	8
 57#define SFTIME_SCKR_POS_MASK	0x00000F00
 58/* SCK Period */
 59#define SFTIME_SCK_PER_OFFSET	0
 60#define SFTIME_SCK_PER_MASK	0x0000000F
 61/* SCK Fall-edge Position */
 62#define SFTIME_SCKF_POS_OFFSET	12
 63#define SFTIME_SCKF_POS_MASK	0x0000F000
 64/* Device Size */
 65#define SFCON_DEV_SIZE_A23_0	0x03000000
 66#define SFCON_DEV_SIZE_MASK	0x0F000000
 67/* Read Data Position */
 68#define SFTIME_RD_POS_MASK	0x000F0000
 69/* Data Output */
 70#define SFIO_UNUSED_WD_MASK	0x0000000F
 71/* Command Opcode mask */
 72#define SFCMD_OPC_MASK		0x000000FF
 73/* dlen bytes of data to write */
 74#define SFCMD_DIR_WRITE		0x00000100
 75/* Data Length offset */
 76#define SFCMD_DLEN_OFFSET	9
 77/* Command Error */
 78#define SFSTAT_CMD_ERR		0x20000000
 79/* Access Command Pending */
 80#define SFSTAT_CMD_PEND		0x00400000
 81/* Frequency set to 100MHz. */
 82#define EBUCC_EBUDIV_SELF100	0x00000001
 83/* Serial Flash */
 84#define BUSRCON0_AGEN_SERIAL_FLASH	0xF0000000
 85/* 8-bit multiplexed */
 86#define BUSRCON0_PORTW_8_BIT_MUX	0x00000000
 87/* Serial Flash */
 88#define BUSWCON0_AGEN_SERIAL_FLASH	0xF0000000
 89/* Chip Select after opcode */
 90#define SFCMD_KEEP_CS_KEEP_SELECTED	0x00008000
 91
 92#define CLOCK_100M	100000000
 93#define CLOCK_50M	50000000
 94
 95struct falcon_sflash {
 96	u32 sfcmd; /* for caching of opcode, direction, ... */
 97	struct spi_master *master;
 98};
 99
100int falcon_sflash_xfer(struct spi_device *spi, struct spi_transfer *t,
101		unsigned long flags)
102{
103	struct device *dev = &spi->dev;
104	struct falcon_sflash *priv = spi_master_get_devdata(spi->master);
105	const u8 *txp = t->tx_buf;
106	u8 *rxp = t->rx_buf;
107	unsigned int bytelen = ((8 * t->len + 7) / 8);
108	unsigned int len, alen, dumlen;
109	u32 val;
110	enum {
111		state_init,
112		state_command_prepare,
113		state_write,
114		state_read,
115		state_disable_cs,
116		state_end
117	} state = state_init;
118
119	do {
120		switch (state) {
121		case state_init: /* detect phase of upper layer sequence */
122		{
123			/* initial write ? */
124			if (flags & FALCON_SPI_XFER_BEGIN) {
125				if (!txp) {
126					dev_err(dev,
127						"BEGIN without tx data!\n");
128					return -ENODATA;
129				}
130				/*
131				 * Prepare the parts of the sfcmd register,
132				 * which should not change during a sequence!
133				 * Only exception are the length fields,
134				 * especially alen and dumlen.
135				 */
136
137				priv->sfcmd = ((spi->chip_select
138						<< SFCMD_CS_OFFSET)
139					       & SFCMD_CS_MASK);
140				priv->sfcmd |= SFCMD_KEEP_CS_KEEP_SELECTED;
141				priv->sfcmd |= *txp;
142				txp++;
143				bytelen--;
144				if (bytelen) {
145					/*
146					 * more data:
147					 * maybe address and/or dummy
148					 */
149					state = state_command_prepare;
150					break;
151				} else {
152					dev_dbg(dev, "write cmd %02X\n",
153						priv->sfcmd & SFCMD_OPC_MASK);
154				}
155			}
156			/* continued write ? */
157			if (txp && bytelen) {
158				state = state_write;
159				break;
160			}
161			/* read data? */
162			if (rxp && bytelen) {
163				state = state_read;
164				break;
165			}
166			/* end of sequence? */
167			if (flags & FALCON_SPI_XFER_END)
168				state = state_disable_cs;
169			else
170				state = state_end;
171			break;
172		}
173		/* collect tx data for address and dummy phase */
174		case state_command_prepare:
175		{
176			/* txp is valid, already checked */
177			val = 0;
178			alen = 0;
179			dumlen = 0;
180			while (bytelen > 0) {
181				if (alen < 3) {
182					val = (val << 8) | (*txp++);
183					alen++;
184				} else if ((dumlen < 15) && (*txp == 0)) {
185					/*
186					 * assume dummy bytes are set to 0
187					 * from upper layer
188					 */
189					dumlen++;
190					txp++;
191				} else {
192					break;
193				}
194				bytelen--;
195			}
196			priv->sfcmd &= ~(SFCMD_ALEN_MASK | SFCMD_DUMLEN_MASK);
197			priv->sfcmd |= (alen << SFCMD_ALEN_OFFSET) |
198					 (dumlen << SFCMD_DUMLEN_OFFSET);
199			if (alen > 0)
200				ltq_ebu_w32(val, SFADDR);
201
202			dev_dbg(dev, "wr %02X, alen=%d (addr=%06X) dlen=%d\n",
203				priv->sfcmd & SFCMD_OPC_MASK,
204				alen, val, dumlen);
205
206			if (bytelen > 0) {
207				/* continue with write */
208				state = state_write;
209			} else if (flags & FALCON_SPI_XFER_END) {
210				/* end of sequence? */
211				state = state_disable_cs;
212			} else {
213				/*
214				 * go to end and expect another
215				 * call (read or write)
216				 */
217				state = state_end;
218			}
219			break;
220		}
221		case state_write:
222		{
223			/* txp still valid */
224			priv->sfcmd |= SFCMD_DIR_WRITE;
225			len = 0;
226			val = 0;
227			do {
228				if (bytelen--)
229					val |= (*txp++) << (8 * len++);
230				if ((flags & FALCON_SPI_XFER_END)
231				    && (bytelen == 0)) {
232					priv->sfcmd &=
233						~SFCMD_KEEP_CS_KEEP_SELECTED;
234				}
235				if ((len == 4) || (bytelen == 0)) {
236					ltq_ebu_w32(val, SFDATA);
237					ltq_ebu_w32(priv->sfcmd
238						| (len<<SFCMD_DLEN_OFFSET),
239						SFCMD);
240					len = 0;
241					val = 0;
242					priv->sfcmd &= ~(SFCMD_ALEN_MASK
243							 | SFCMD_DUMLEN_MASK);
244				}
245			} while (bytelen);
246			state = state_end;
247			break;
248		}
249		case state_read:
250		{
251			/* read data */
252			priv->sfcmd &= ~SFCMD_DIR_WRITE;
253			do {
254				if ((flags & FALCON_SPI_XFER_END)
255				    && (bytelen <= 4)) {
256					priv->sfcmd &=
257						~SFCMD_KEEP_CS_KEEP_SELECTED;
258				}
259				len = (bytelen > 4) ? 4 : bytelen;
260				bytelen -= len;
261				ltq_ebu_w32(priv->sfcmd
262					| (len << SFCMD_DLEN_OFFSET), SFCMD);
263				priv->sfcmd &= ~(SFCMD_ALEN_MASK
264						 | SFCMD_DUMLEN_MASK);
265				do {
266					val = ltq_ebu_r32(SFSTAT);
267					if (val & SFSTAT_CMD_ERR) {
268						/* reset error status */
269						dev_err(dev, "SFSTAT: CMD_ERR");
270						dev_err(dev, " (%x)\n", val);
271						ltq_ebu_w32(SFSTAT_CMD_ERR,
272							SFSTAT);
273						return -EBADE;
274					}
275				} while (val & SFSTAT_CMD_PEND);
276				val = ltq_ebu_r32(SFDATA);
277				do {
278					*rxp = (val & 0xFF);
279					rxp++;
280					val >>= 8;
281					len--;
282				} while (len);
283			} while (bytelen);
284			state = state_end;
285			break;
286		}
287		case state_disable_cs:
288		{
289			priv->sfcmd &= ~SFCMD_KEEP_CS_KEEP_SELECTED;
290			ltq_ebu_w32(priv->sfcmd | (0 << SFCMD_DLEN_OFFSET),
291				SFCMD);
292			val = ltq_ebu_r32(SFSTAT);
293			if (val & SFSTAT_CMD_ERR) {
294				/* reset error status */
295				dev_err(dev, "SFSTAT: CMD_ERR (%x)\n", val);
296				ltq_ebu_w32(SFSTAT_CMD_ERR, SFSTAT);
297				return -EBADE;
298			}
299			state = state_end;
300			break;
301		}
302		case state_end:
303			break;
304		}
305	} while (state != state_end);
306
307	return 0;
308}
309
310static int falcon_sflash_setup(struct spi_device *spi)
311{
312	unsigned int i;
313	unsigned long flags;
314
315	spin_lock_irqsave(&ebu_lock, flags);
316
317	if (spi->max_speed_hz >= CLOCK_100M) {
318		/* set EBU clock to 100 MHz */
319		ltq_sys1_w32_mask(0, EBUCC_EBUDIV_SELF100, EBUCC);
320		i = 1; /* divider */
321	} else {
322		/* set EBU clock to 50 MHz */
323		ltq_sys1_w32_mask(EBUCC_EBUDIV_SELF100, 0, EBUCC);
324
325		/* search for suitable divider */
326		for (i = 1; i < 7; i++) {
327			if (CLOCK_50M / i <= spi->max_speed_hz)
328				break;
329		}
330	}
331
332	/* setup period of serial clock */
333	ltq_ebu_w32_mask(SFTIME_SCKF_POS_MASK
334		     | SFTIME_SCKR_POS_MASK
335		     | SFTIME_SCK_PER_MASK,
336		     (i << SFTIME_SCKR_POS_OFFSET)
337		     | (i << (SFTIME_SCK_PER_OFFSET + 1)),
338		     SFTIME);
339
340	/*
341	 * set some bits of unused_wd, to not trigger HOLD/WP
342	 * signals on non QUAD flashes
343	 */
344	ltq_ebu_w32((SFIO_UNUSED_WD_MASK & (0x8 | 0x4)), SFIO);
345
346	ltq_ebu_w32(BUSRCON0_AGEN_SERIAL_FLASH | BUSRCON0_PORTW_8_BIT_MUX,
347			BUSRCON0);
348	ltq_ebu_w32(BUSWCON0_AGEN_SERIAL_FLASH, BUSWCON0);
349	/* set address wrap around to maximum for 24-bit addresses */
350	ltq_ebu_w32_mask(SFCON_DEV_SIZE_MASK, SFCON_DEV_SIZE_A23_0, SFCON);
351
352	spin_unlock_irqrestore(&ebu_lock, flags);
353
354	return 0;
355}
356
357static int falcon_sflash_prepare_xfer(struct spi_master *master)
358{
359	return 0;
360}
361
362static int falcon_sflash_unprepare_xfer(struct spi_master *master)
363{
364	return 0;
365}
366
367static int falcon_sflash_xfer_one(struct spi_master *master,
368					struct spi_message *m)
369{
370	struct falcon_sflash *priv = spi_master_get_devdata(master);
371	struct spi_transfer *t;
372	unsigned long spi_flags;
373	unsigned long flags;
374	int ret = 0;
375
376	priv->sfcmd = 0;
377	m->actual_length = 0;
378
379	spi_flags = FALCON_SPI_XFER_BEGIN;
380	list_for_each_entry(t, &m->transfers, transfer_list) {
381		if (list_is_last(&t->transfer_list, &m->transfers))
382			spi_flags |= FALCON_SPI_XFER_END;
383
384		spin_lock_irqsave(&ebu_lock, flags);
385		ret = falcon_sflash_xfer(m->spi, t, spi_flags);
386		spin_unlock_irqrestore(&ebu_lock, flags);
387
388		if (ret)
389			break;
390
391		m->actual_length += t->len;
392
393		WARN_ON(t->delay_usecs || t->cs_change);
394		spi_flags = 0;
395	}
396
397	m->status = ret;
398	spi_finalize_current_message(master);
399
400	return 0;
401}
402
403static int falcon_sflash_probe(struct platform_device *pdev)
404{
405	struct falcon_sflash *priv;
406	struct spi_master *master;
407	int ret;
408
409	if (ltq_boot_select() != BS_SPI) {
410		dev_err(&pdev->dev, "invalid bootstrap options\n");
411		return -ENODEV;
412	}
413
414	master = spi_alloc_master(&pdev->dev, sizeof(*priv));
415	if (!master)
416		return -ENOMEM;
417
418	priv = spi_master_get_devdata(master);
419	priv->master = master;
420
421	master->mode_bits = SPI_MODE_3;
422	master->flags = SPI_MASTER_HALF_DUPLEX;
423	master->setup = falcon_sflash_setup;
424	master->prepare_transfer_hardware = falcon_sflash_prepare_xfer;
425	master->transfer_one_message = falcon_sflash_xfer_one;
426	master->unprepare_transfer_hardware = falcon_sflash_unprepare_xfer;
427	master->dev.of_node = pdev->dev.of_node;
428
429	platform_set_drvdata(pdev, priv);
 
 
 
 
430
431	ret = devm_spi_register_master(&pdev->dev, master);
432	if (ret)
433		spi_master_put(master);
434	return ret;
435}
436
437static const struct of_device_id falcon_sflash_match[] = {
438	{ .compatible = "lantiq,sflash-falcon" },
439	{},
440};
441MODULE_DEVICE_TABLE(of, falcon_sflash_match);
442
443static struct platform_driver falcon_sflash_driver = {
444	.probe	= falcon_sflash_probe,
445	.driver = {
446		.name	= DRV_NAME,
447		.owner	= THIS_MODULE,
448		.of_match_table = falcon_sflash_match,
449	}
450};
451
452module_platform_driver(falcon_sflash_driver);
453
454MODULE_LICENSE("GPL");
455MODULE_DESCRIPTION("Lantiq Falcon SPI/SFLASH controller driver");