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v6.8
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * DDR PHY Front End (DPFE) driver for Broadcom set top box SoCs
  4 *
  5 * Copyright (c) 2017 Broadcom
  6 */
  7
  8/*
  9 * This driver provides access to the DPFE interface of Broadcom STB SoCs.
 10 * The firmware running on the DCPU inside the DDR PHY can provide current
 11 * information about the system's RAM, for instance the DRAM refresh rate.
 12 * This can be used as an indirect indicator for the DRAM's temperature.
 13 * Slower refresh rate means cooler RAM, higher refresh rate means hotter
 14 * RAM.
 15 *
 16 * Throughout the driver, we use readl_relaxed() and writel_relaxed(), which
 17 * already contain the appropriate le32_to_cpu()/cpu_to_le32() calls.
 18 *
 19 * Note regarding the loading of the firmware image: we use be32_to_cpu()
 20 * and le_32_to_cpu(), so we can support the following four cases:
 21 *     - LE kernel + LE firmware image (the most common case)
 22 *     - LE kernel + BE firmware image
 23 *     - BE kernel + LE firmware image
 24 *     - BE kernel + BE firmware image
 25 *
 26 * The DPCU always runs in big endian mode. The firmware image, however, can
 27 * be in either format. Also, communication between host CPU and DCPU is
 28 * always in little endian.
 29 */
 30
 31#include <linux/delay.h>
 32#include <linux/firmware.h>
 33#include <linux/io.h>
 34#include <linux/module.h>
 35#include <linux/of.h>
 
 36#include <linux/platform_device.h>
 37
 38#define DRVNAME			"brcmstb-dpfe"
 39
 40/* DCPU register offsets */
 41#define REG_DCPU_RESET		0x0
 42#define REG_TO_DCPU_MBOX	0x10
 43#define REG_TO_HOST_MBOX	0x14
 44
 45/* Macros to process offsets returned by the DCPU */
 46#define DRAM_MSG_ADDR_OFFSET	0x0
 47#define DRAM_MSG_TYPE_OFFSET	0x1c
 48#define DRAM_MSG_ADDR_MASK	((1UL << DRAM_MSG_TYPE_OFFSET) - 1)
 49#define DRAM_MSG_TYPE_MASK	((1UL << \
 50				 (BITS_PER_LONG - DRAM_MSG_TYPE_OFFSET)) - 1)
 51
 52/* Message RAM */
 53#define DCPU_MSG_RAM_START	0x100
 54#define DCPU_MSG_RAM(x)		(DCPU_MSG_RAM_START + (x) * sizeof(u32))
 55
 56/* DRAM Info Offsets & Masks */
 57#define DRAM_INFO_INTERVAL	0x0
 58#define DRAM_INFO_MR4		0x4
 59#define DRAM_INFO_ERROR		0x8
 60#define DRAM_INFO_MR4_MASK	0xff
 61#define DRAM_INFO_MR4_SHIFT	24	/* We need to look at byte 3 */
 62
 63/* DRAM MR4 Offsets & Masks */
 64#define DRAM_MR4_REFRESH	0x0	/* Refresh rate */
 65#define DRAM_MR4_SR_ABORT	0x3	/* Self Refresh Abort */
 66#define DRAM_MR4_PPRE		0x4	/* Post-package repair entry/exit */
 67#define DRAM_MR4_TH_OFFS	0x5	/* Thermal Offset; vendor specific */
 68#define DRAM_MR4_TUF		0x7	/* Temperature Update Flag */
 69
 70#define DRAM_MR4_REFRESH_MASK	0x7
 71#define DRAM_MR4_SR_ABORT_MASK	0x1
 72#define DRAM_MR4_PPRE_MASK	0x1
 73#define DRAM_MR4_TH_OFFS_MASK	0x3
 74#define DRAM_MR4_TUF_MASK	0x1
 75
 76/* DRAM Vendor Offsets & Masks (API v2) */
 77#define DRAM_VENDOR_MR5		0x0
 78#define DRAM_VENDOR_MR6		0x4
 79#define DRAM_VENDOR_MR7		0x8
 80#define DRAM_VENDOR_MR8		0xc
 81#define DRAM_VENDOR_ERROR	0x10
 82#define DRAM_VENDOR_MASK	0xff
 83#define DRAM_VENDOR_SHIFT	24	/* We need to look at byte 3 */
 84
 85/* DRAM Information Offsets & Masks (API v3) */
 86#define DRAM_DDR_INFO_MR4	0x0
 87#define DRAM_DDR_INFO_MR5	0x4
 88#define DRAM_DDR_INFO_MR6	0x8
 89#define DRAM_DDR_INFO_MR7	0xc
 90#define DRAM_DDR_INFO_MR8	0x10
 91#define DRAM_DDR_INFO_ERROR	0x14
 92#define DRAM_DDR_INFO_MASK	0xff
 93
 94/* Reset register bits & masks */
 95#define DCPU_RESET_SHIFT	0x0
 96#define DCPU_RESET_MASK		0x1
 97#define DCPU_CLK_DISABLE_SHIFT	0x2
 98
 99/* DCPU return codes */
100#define DCPU_RET_ERROR_BIT	BIT(31)
101#define DCPU_RET_SUCCESS	0x1
102#define DCPU_RET_ERR_HEADER	(DCPU_RET_ERROR_BIT | BIT(0))
103#define DCPU_RET_ERR_INVAL	(DCPU_RET_ERROR_BIT | BIT(1))
104#define DCPU_RET_ERR_CHKSUM	(DCPU_RET_ERROR_BIT | BIT(2))
105#define DCPU_RET_ERR_COMMAND	(DCPU_RET_ERROR_BIT | BIT(3))
106/* This error code is not firmware defined and only used in the driver. */
107#define DCPU_RET_ERR_TIMEDOUT	(DCPU_RET_ERROR_BIT | BIT(4))
108
109/* Firmware magic */
110#define DPFE_BE_MAGIC		0xfe1010fe
111#define DPFE_LE_MAGIC		0xfe0101fe
112
113/* Error codes */
114#define ERR_INVALID_MAGIC	-1
115#define ERR_INVALID_SIZE	-2
116#define ERR_INVALID_CHKSUM	-3
117
118/* Message types */
119#define DPFE_MSG_TYPE_COMMAND	1
120#define DPFE_MSG_TYPE_RESPONSE	2
121
122#define DELAY_LOOP_MAX		1000
123
124enum dpfe_msg_fields {
125	MSG_HEADER,
126	MSG_COMMAND,
127	MSG_ARG_COUNT,
128	MSG_ARG0,
 
129	MSG_FIELD_MAX	= 16 /* Max number of arguments */
130};
131
132enum dpfe_commands {
133	DPFE_CMD_GET_INFO,
134	DPFE_CMD_GET_REFRESH,
135	DPFE_CMD_GET_VENDOR,
136	DPFE_CMD_MAX /* Last entry */
137};
138
139/*
140 * Format of the binary firmware file:
141 *
142 *   entry
143 *      0    header
144 *              value:  0xfe0101fe  <== little endian
145 *                      0xfe1010fe  <== big endian
146 *      1    sequence:
147 *              [31:16] total segments on this build
148 *              [15:0]  this segment sequence.
149 *      2    FW version
150 *      3    IMEM byte size
151 *      4    DMEM byte size
152 *           IMEM
153 *           DMEM
154 *      last checksum ==> sum of everything
155 */
156struct dpfe_firmware_header {
157	u32 magic;
158	u32 sequence;
159	u32 version;
160	u32 imem_size;
161	u32 dmem_size;
162};
163
164/* Things we only need during initialization. */
165struct init_data {
166	unsigned int dmem_len;
167	unsigned int imem_len;
168	unsigned int chksum;
169	bool is_big_endian;
170};
171
172/* API version and corresponding commands */
173struct dpfe_api {
174	int version;
175	const char *fw_name;
176	const struct attribute_group **sysfs_attrs;
177	u32 command[DPFE_CMD_MAX][MSG_FIELD_MAX];
178};
179
180/* Things we need for as long as we are active. */
181struct brcmstb_dpfe_priv {
182	void __iomem *regs;
183	void __iomem *dmem;
184	void __iomem *imem;
185	struct device *dev;
186	const struct dpfe_api *dpfe_api;
187	struct mutex lock;
188};
189
 
 
 
 
 
190/*
191 * Forward declaration of our sysfs attribute functions, so we can declare the
192 * attribute data structures early.
193 */
194static ssize_t show_info(struct device *, struct device_attribute *, char *);
195static ssize_t show_refresh(struct device *, struct device_attribute *, char *);
196static ssize_t store_refresh(struct device *, struct device_attribute *,
197			  const char *, size_t);
198static ssize_t show_vendor(struct device *, struct device_attribute *, char *);
199static ssize_t show_dram(struct device *, struct device_attribute *, char *);
200
201/*
202 * Declare our attributes early, so they can be referenced in the API data
203 * structure. We need to do this, because the attributes depend on the API
204 * version.
205 */
206static DEVICE_ATTR(dpfe_info, 0444, show_info, NULL);
207static DEVICE_ATTR(dpfe_refresh, 0644, show_refresh, store_refresh);
208static DEVICE_ATTR(dpfe_vendor, 0444, show_vendor, NULL);
209static DEVICE_ATTR(dpfe_dram, 0444, show_dram, NULL);
210
211/* API v2 sysfs attributes */
212static struct attribute *dpfe_v2_attrs[] = {
213	&dev_attr_dpfe_info.attr,
214	&dev_attr_dpfe_refresh.attr,
215	&dev_attr_dpfe_vendor.attr,
216	NULL
217};
218ATTRIBUTE_GROUPS(dpfe_v2);
219
220/* API v3 sysfs attributes */
221static struct attribute *dpfe_v3_attrs[] = {
222	&dev_attr_dpfe_info.attr,
223	&dev_attr_dpfe_dram.attr,
224	NULL
225};
226ATTRIBUTE_GROUPS(dpfe_v3);
227
228/*
229 * Old API v2 firmware commands, as defined in the rev 0.61 specification, we
230 * use a version set to 1 to denote that it is not compatible with the new API
231 * v2 and onwards.
232 */
233static const struct dpfe_api dpfe_api_old_v2 = {
234	.version = 1,
235	.fw_name = "dpfe.bin",
236	.sysfs_attrs = dpfe_v2_groups,
237	.command = {
238		[DPFE_CMD_GET_INFO] = {
239			[MSG_HEADER] = DPFE_MSG_TYPE_COMMAND,
240			[MSG_COMMAND] = 1,
241			[MSG_ARG_COUNT] = 1,
242			[MSG_ARG0] = 1,
 
243		},
244		[DPFE_CMD_GET_REFRESH] = {
245			[MSG_HEADER] = DPFE_MSG_TYPE_COMMAND,
246			[MSG_COMMAND] = 2,
247			[MSG_ARG_COUNT] = 1,
248			[MSG_ARG0] = 1,
 
249		},
250		[DPFE_CMD_GET_VENDOR] = {
251			[MSG_HEADER] = DPFE_MSG_TYPE_COMMAND,
252			[MSG_COMMAND] = 2,
253			[MSG_ARG_COUNT] = 1,
254			[MSG_ARG0] = 2,
255		},
256	}
257};
258
259/*
260 * API v2 firmware commands, as defined in the rev 0.8 specification, named new
261 * v2 here
262 */
263static const struct dpfe_api dpfe_api_new_v2 = {
264	.version = 2,
265	.fw_name = NULL, /* We expect the firmware to have been downloaded! */
266	.sysfs_attrs = dpfe_v2_groups,
267	.command = {
268		[DPFE_CMD_GET_INFO] = {
269			[MSG_HEADER] = DPFE_MSG_TYPE_COMMAND,
270			[MSG_COMMAND] = 0x101,
271		},
272		[DPFE_CMD_GET_REFRESH] = {
273			[MSG_HEADER] = DPFE_MSG_TYPE_COMMAND,
274			[MSG_COMMAND] = 0x201,
275		},
276		[DPFE_CMD_GET_VENDOR] = {
277			[MSG_HEADER] = DPFE_MSG_TYPE_COMMAND,
278			[MSG_COMMAND] = 0x202,
279		},
280	}
281};
282
283/* API v3 firmware commands */
284static const struct dpfe_api dpfe_api_v3 = {
285	.version = 3,
286	.fw_name = NULL, /* We expect the firmware to have been downloaded! */
287	.sysfs_attrs = dpfe_v3_groups,
288	.command = {
289		[DPFE_CMD_GET_INFO] = {
290			[MSG_HEADER] = DPFE_MSG_TYPE_COMMAND,
291			[MSG_COMMAND] = 0x0101,
292			[MSG_ARG_COUNT] = 1,
293			[MSG_ARG0] = 1,
 
294		},
295		[DPFE_CMD_GET_REFRESH] = {
296			[MSG_HEADER] = DPFE_MSG_TYPE_COMMAND,
297			[MSG_COMMAND] = 0x0202,
298			[MSG_ARG_COUNT] = 0,
 
 
 
 
 
 
299		},
300		/* There's no GET_VENDOR command in API v3. */
301	},
302};
303
304static const char *get_error_text(unsigned int i)
305{
306	static const char * const error_text[] = {
307		"Success", "Header code incorrect",
308		"Unknown command or argument", "Incorrect checksum",
309		"Malformed command", "Timed out", "Unknown error",
310	};
311
312	if (unlikely(i >= ARRAY_SIZE(error_text)))
313		i = ARRAY_SIZE(error_text) - 1;
314
315	return error_text[i];
316}
317
318static bool is_dcpu_enabled(struct brcmstb_dpfe_priv *priv)
319{
320	u32 val;
321
322	mutex_lock(&priv->lock);
323	val = readl_relaxed(priv->regs + REG_DCPU_RESET);
324	mutex_unlock(&priv->lock);
325
326	return !(val & DCPU_RESET_MASK);
327}
328
329static void __disable_dcpu(struct brcmstb_dpfe_priv *priv)
330{
331	u32 val;
332
333	if (!is_dcpu_enabled(priv))
334		return;
335
336	mutex_lock(&priv->lock);
337
338	/* Put DCPU in reset if it's running. */
339	val = readl_relaxed(priv->regs + REG_DCPU_RESET);
340	val |= (1 << DCPU_RESET_SHIFT);
341	writel_relaxed(val, priv->regs + REG_DCPU_RESET);
342
343	mutex_unlock(&priv->lock);
344}
345
346static void __enable_dcpu(struct brcmstb_dpfe_priv *priv)
347{
348	void __iomem *regs = priv->regs;
349	u32 val;
350
351	mutex_lock(&priv->lock);
352
353	/* Clear mailbox registers. */
354	writel_relaxed(0, regs + REG_TO_DCPU_MBOX);
355	writel_relaxed(0, regs + REG_TO_HOST_MBOX);
356
357	/* Disable DCPU clock gating */
358	val = readl_relaxed(regs + REG_DCPU_RESET);
359	val &= ~(1 << DCPU_CLK_DISABLE_SHIFT);
360	writel_relaxed(val, regs + REG_DCPU_RESET);
361
362	/* Take DCPU out of reset */
363	val = readl_relaxed(regs + REG_DCPU_RESET);
364	val &= ~(1 << DCPU_RESET_SHIFT);
365	writel_relaxed(val, regs + REG_DCPU_RESET);
366
367	mutex_unlock(&priv->lock);
368}
369
370static unsigned int get_msg_chksum(const u32 msg[], unsigned int max)
371{
372	unsigned int sum = 0;
373	unsigned int i;
374
375	/* Don't include the last field in the checksum. */
376	for (i = 0; i < max; i++)
377		sum += msg[i];
378
379	return sum;
380}
381
382static void __iomem *get_msg_ptr(struct brcmstb_dpfe_priv *priv, u32 response,
383				 char *buf, ssize_t *size)
384{
385	unsigned int msg_type;
386	unsigned int offset;
387	void __iomem *ptr = NULL;
388
389	/* There is no need to use this function for API v3 or later. */
390	if (unlikely(priv->dpfe_api->version >= 3))
391		return NULL;
 
392
393	msg_type = (response >> DRAM_MSG_TYPE_OFFSET) & DRAM_MSG_TYPE_MASK;
394	offset = (response >> DRAM_MSG_ADDR_OFFSET) & DRAM_MSG_ADDR_MASK;
395
396	/*
397	 * msg_type == 1: the offset is relative to the message RAM
398	 * msg_type == 0: the offset is relative to the data RAM (this is the
399	 *                previous way of passing data)
400	 * msg_type is anything else: there's critical hardware problem
401	 */
402	switch (msg_type) {
403	case 1:
404		ptr = priv->regs + DCPU_MSG_RAM_START + offset;
405		break;
406	case 0:
407		ptr = priv->dmem + offset;
408		break;
409	default:
410		dev_emerg(priv->dev, "invalid message reply from DCPU: %#x\n",
411			response);
412		if (buf && size)
413			*size = sprintf(buf,
414				"FATAL: communication error with DCPU\n");
415	}
416
417	return ptr;
418}
419
420static void __finalize_command(struct brcmstb_dpfe_priv *priv)
421{
422	unsigned int release_mbox;
423
424	/*
425	 * It depends on the API version which MBOX register we have to write to
426	 * signal we are done.
427	 */
428	release_mbox = (priv->dpfe_api->version < 2)
429			? REG_TO_HOST_MBOX : REG_TO_DCPU_MBOX;
430	writel_relaxed(0, priv->regs + release_mbox);
431}
432
433static int __send_command(struct brcmstb_dpfe_priv *priv, unsigned int cmd,
434			  u32 result[])
435{
 
436	void __iomem *regs = priv->regs;
437	unsigned int i, chksum, chksum_idx;
438	const u32 *msg;
439	int ret = 0;
440	u32 resp;
441
442	if (cmd >= DPFE_CMD_MAX)
443		return -1;
444
445	msg = priv->dpfe_api->command[cmd];
446
447	mutex_lock(&priv->lock);
448
449	/* Wait for DCPU to become ready */
450	for (i = 0; i < DELAY_LOOP_MAX; i++) {
451		resp = readl_relaxed(regs + REG_TO_HOST_MBOX);
452		if (resp == 0)
453			break;
454		msleep(1);
455	}
456	if (resp != 0) {
457		mutex_unlock(&priv->lock);
458		return -ffs(DCPU_RET_ERR_TIMEDOUT);
459	}
460
461	/* Compute checksum over the message */
462	chksum_idx = msg[MSG_ARG_COUNT] + MSG_ARG_COUNT + 1;
463	chksum = get_msg_chksum(msg, chksum_idx);
464
465	/* Write command and arguments to message area */
466	for (i = 0; i < MSG_FIELD_MAX; i++) {
467		if (i == chksum_idx)
468			writel_relaxed(chksum, regs + DCPU_MSG_RAM(i));
469		else
470			writel_relaxed(msg[i], regs + DCPU_MSG_RAM(i));
471	}
472
473	/* Tell DCPU there is a command waiting */
474	writel_relaxed(1, regs + REG_TO_DCPU_MBOX);
475
476	/* Wait for DCPU to process the command */
477	for (i = 0; i < DELAY_LOOP_MAX; i++) {
478		/* Read response code */
479		resp = readl_relaxed(regs + REG_TO_HOST_MBOX);
480		if (resp > 0)
481			break;
482		msleep(1);
483	}
484
485	if (i == DELAY_LOOP_MAX) {
486		resp = (DCPU_RET_ERR_TIMEDOUT & ~DCPU_RET_ERROR_BIT);
487		ret = -ffs(resp);
488	} else {
489		/* Read response data */
490		for (i = 0; i < MSG_FIELD_MAX; i++)
491			result[i] = readl_relaxed(regs + DCPU_MSG_RAM(i));
492		chksum_idx = result[MSG_ARG_COUNT] + MSG_ARG_COUNT + 1;
493	}
494
495	/* Tell DCPU we are done */
496	__finalize_command(priv);
497
498	mutex_unlock(&priv->lock);
499
500	if (ret)
501		return ret;
502
503	/* Verify response */
504	chksum = get_msg_chksum(result, chksum_idx);
505	if (chksum != result[chksum_idx])
506		resp = DCPU_RET_ERR_CHKSUM;
507
508	if (resp != DCPU_RET_SUCCESS) {
509		resp &= ~DCPU_RET_ERROR_BIT;
510		ret = -ffs(resp);
511	}
512
513	return ret;
514}
515
516/* Ensure that the firmware file loaded meets all the requirements. */
517static int __verify_firmware(struct init_data *init,
518			     const struct firmware *fw)
519{
520	const struct dpfe_firmware_header *header = (void *)fw->data;
521	unsigned int dmem_size, imem_size, total_size;
522	bool is_big_endian = false;
523	const u32 *chksum_ptr;
524
525	if (header->magic == DPFE_BE_MAGIC)
526		is_big_endian = true;
527	else if (header->magic != DPFE_LE_MAGIC)
528		return ERR_INVALID_MAGIC;
529
530	if (is_big_endian) {
531		dmem_size = be32_to_cpu(header->dmem_size);
532		imem_size = be32_to_cpu(header->imem_size);
533	} else {
534		dmem_size = le32_to_cpu(header->dmem_size);
535		imem_size = le32_to_cpu(header->imem_size);
536	}
537
538	/* Data and instruction sections are 32 bit words. */
539	if ((dmem_size % sizeof(u32)) != 0 || (imem_size % sizeof(u32)) != 0)
540		return ERR_INVALID_SIZE;
541
542	/*
543	 * The header + the data section + the instruction section + the
544	 * checksum must be equal to the total firmware size.
545	 */
546	total_size = dmem_size + imem_size + sizeof(*header) +
547		sizeof(*chksum_ptr);
548	if (total_size != fw->size)
549		return ERR_INVALID_SIZE;
550
551	/* The checksum comes at the very end. */
552	chksum_ptr = (void *)fw->data + sizeof(*header) + dmem_size + imem_size;
553
554	init->is_big_endian = is_big_endian;
555	init->dmem_len = dmem_size;
556	init->imem_len = imem_size;
557	init->chksum = (is_big_endian)
558		? be32_to_cpu(*chksum_ptr) : le32_to_cpu(*chksum_ptr);
559
560	return 0;
561}
562
563/* Verify checksum by reading back the firmware from co-processor RAM. */
564static int __verify_fw_checksum(struct init_data *init,
565				struct brcmstb_dpfe_priv *priv,
566				const struct dpfe_firmware_header *header,
567				u32 checksum)
568{
569	u32 magic, sequence, version, sum;
570	u32 __iomem *dmem = priv->dmem;
571	u32 __iomem *imem = priv->imem;
572	unsigned int i;
573
574	if (init->is_big_endian) {
575		magic = be32_to_cpu(header->magic);
576		sequence = be32_to_cpu(header->sequence);
577		version = be32_to_cpu(header->version);
578	} else {
579		magic = le32_to_cpu(header->magic);
580		sequence = le32_to_cpu(header->sequence);
581		version = le32_to_cpu(header->version);
582	}
583
584	sum = magic + sequence + version + init->dmem_len + init->imem_len;
585
586	for (i = 0; i < init->dmem_len / sizeof(u32); i++)
587		sum += readl_relaxed(dmem + i);
588
589	for (i = 0; i < init->imem_len / sizeof(u32); i++)
590		sum += readl_relaxed(imem + i);
591
592	return (sum == checksum) ? 0 : -1;
593}
594
595static int __write_firmware(u32 __iomem *mem, const u32 *fw,
596			    unsigned int size, bool is_big_endian)
597{
598	unsigned int i;
599
600	/* Convert size to 32-bit words. */
601	size /= sizeof(u32);
602
603	/* It is recommended to clear the firmware area first. */
604	for (i = 0; i < size; i++)
605		writel_relaxed(0, mem + i);
606
607	/* Now copy it. */
608	if (is_big_endian) {
609		for (i = 0; i < size; i++)
610			writel_relaxed(be32_to_cpu(fw[i]), mem + i);
611	} else {
612		for (i = 0; i < size; i++)
613			writel_relaxed(le32_to_cpu(fw[i]), mem + i);
614	}
615
616	return 0;
617}
618
619static int brcmstb_dpfe_download_firmware(struct brcmstb_dpfe_priv *priv)
 
620{
621	const struct dpfe_firmware_header *header;
622	unsigned int dmem_size, imem_size;
623	struct device *dev = priv->dev;
624	bool is_big_endian = false;
 
625	const struct firmware *fw;
626	const u32 *dmem, *imem;
627	struct init_data init;
628	const void *fw_blob;
629	int ret;
630
 
 
631	/*
632	 * Skip downloading the firmware if the DCPU is already running and
633	 * responding to commands.
634	 */
635	if (is_dcpu_enabled(priv)) {
636		u32 response[MSG_FIELD_MAX];
637
638		ret = __send_command(priv, DPFE_CMD_GET_INFO, response);
639		if (!ret)
640			return 0;
641	}
642
643	/*
644	 * If the firmware filename is NULL it means the boot firmware has to
645	 * download the DCPU firmware for us. If that didn't work, we have to
646	 * bail, since downloading it ourselves wouldn't work either.
647	 */
648	if (!priv->dpfe_api->fw_name)
649		return -ENODEV;
650
651	ret = firmware_request_nowarn(&fw, priv->dpfe_api->fw_name, dev);
652	/*
653	 * Defer the firmware download if the firmware file couldn't be found.
654	 * The root file system may not be available yet.
655	 */
656	if (ret)
657		return (ret == -ENOENT) ? -EPROBE_DEFER : ret;
658
659	ret = __verify_firmware(&init, fw);
660	if (ret) {
661		ret = -EFAULT;
662		goto release_fw;
663	}
664
665	__disable_dcpu(priv);
666
667	is_big_endian = init.is_big_endian;
668	dmem_size = init.dmem_len;
669	imem_size = init.imem_len;
670
671	/* At the beginning of the firmware blob is a header. */
672	header = (struct dpfe_firmware_header *)fw->data;
673	/* Void pointer to the beginning of the actual firmware. */
674	fw_blob = fw->data + sizeof(*header);
675	/* IMEM comes right after the header. */
676	imem = fw_blob;
677	/* DMEM follows after IMEM. */
678	dmem = fw_blob + imem_size;
679
680	ret = __write_firmware(priv->dmem, dmem, dmem_size, is_big_endian);
681	if (ret)
682		goto release_fw;
683	ret = __write_firmware(priv->imem, imem, imem_size, is_big_endian);
684	if (ret)
685		goto release_fw;
686
687	ret = __verify_fw_checksum(&init, priv, header, init.chksum);
688	if (ret)
689		goto release_fw;
690
691	__enable_dcpu(priv);
692
693release_fw:
694	release_firmware(fw);
695	return ret;
696}
697
698static ssize_t generic_show(unsigned int command, u32 response[],
699			    struct brcmstb_dpfe_priv *priv, char *buf)
700{
701	int ret;
702
703	if (!priv)
704		return sprintf(buf, "ERROR: driver private data not set\n");
705
706	ret = __send_command(priv, command, response);
707	if (ret < 0)
708		return sprintf(buf, "ERROR: %s\n", get_error_text(-ret));
709
710	return 0;
711}
712
713static ssize_t show_info(struct device *dev, struct device_attribute *devattr,
714			 char *buf)
715{
716	u32 response[MSG_FIELD_MAX];
717	struct brcmstb_dpfe_priv *priv;
718	unsigned int info;
719	ssize_t ret;
720
721	priv = dev_get_drvdata(dev);
722	ret = generic_show(DPFE_CMD_GET_INFO, response, priv, buf);
723	if (ret)
724		return ret;
725
726	info = response[MSG_ARG0];
727
728	return sprintf(buf, "%u.%u.%u.%u\n",
729		       (info >> 24) & 0xff,
730		       (info >> 16) & 0xff,
731		       (info >> 8) & 0xff,
732		       info & 0xff);
733}
734
735static ssize_t show_refresh(struct device *dev,
736			    struct device_attribute *devattr, char *buf)
737{
738	u32 response[MSG_FIELD_MAX];
739	void __iomem *info;
740	struct brcmstb_dpfe_priv *priv;
741	u8 refresh, sr_abort, ppre, thermal_offs, tuf;
742	u32 mr4;
743	ssize_t ret;
744
745	priv = dev_get_drvdata(dev);
746	ret = generic_show(DPFE_CMD_GET_REFRESH, response, priv, buf);
747	if (ret)
748		return ret;
749
750	info = get_msg_ptr(priv, response[MSG_ARG0], buf, &ret);
751	if (!info)
752		return ret;
753
754	mr4 = (readl_relaxed(info + DRAM_INFO_MR4) >> DRAM_INFO_MR4_SHIFT) &
755	       DRAM_INFO_MR4_MASK;
756
757	refresh = (mr4 >> DRAM_MR4_REFRESH) & DRAM_MR4_REFRESH_MASK;
758	sr_abort = (mr4 >> DRAM_MR4_SR_ABORT) & DRAM_MR4_SR_ABORT_MASK;
759	ppre = (mr4 >> DRAM_MR4_PPRE) & DRAM_MR4_PPRE_MASK;
760	thermal_offs = (mr4 >> DRAM_MR4_TH_OFFS) & DRAM_MR4_TH_OFFS_MASK;
761	tuf = (mr4 >> DRAM_MR4_TUF) & DRAM_MR4_TUF_MASK;
762
763	return sprintf(buf, "%#x %#x %#x %#x %#x %#x %#x\n",
764		       readl_relaxed(info + DRAM_INFO_INTERVAL),
765		       refresh, sr_abort, ppre, thermal_offs, tuf,
766		       readl_relaxed(info + DRAM_INFO_ERROR));
767}
768
769static ssize_t store_refresh(struct device *dev, struct device_attribute *attr,
770			  const char *buf, size_t count)
771{
772	u32 response[MSG_FIELD_MAX];
773	struct brcmstb_dpfe_priv *priv;
774	void __iomem *info;
775	unsigned long val;
776	int ret;
777
778	if (kstrtoul(buf, 0, &val) < 0)
779		return -EINVAL;
780
781	priv = dev_get_drvdata(dev);
782	ret = __send_command(priv, DPFE_CMD_GET_REFRESH, response);
783	if (ret)
784		return ret;
785
786	info = get_msg_ptr(priv, response[MSG_ARG0], NULL, NULL);
787	if (!info)
788		return -EIO;
789
790	writel_relaxed(val, info + DRAM_INFO_INTERVAL);
791
792	return count;
793}
794
795static ssize_t show_vendor(struct device *dev, struct device_attribute *devattr,
796			   char *buf)
797{
798	u32 response[MSG_FIELD_MAX];
799	struct brcmstb_dpfe_priv *priv;
800	void __iomem *info;
801	ssize_t ret;
802	u32 mr5, mr6, mr7, mr8, err;
803
804	priv = dev_get_drvdata(dev);
805	ret = generic_show(DPFE_CMD_GET_VENDOR, response, priv, buf);
806	if (ret)
807		return ret;
808
809	info = get_msg_ptr(priv, response[MSG_ARG0], buf, &ret);
810	if (!info)
811		return ret;
812
813	mr5 = (readl_relaxed(info + DRAM_VENDOR_MR5) >> DRAM_VENDOR_SHIFT) &
814		DRAM_VENDOR_MASK;
815	mr6 = (readl_relaxed(info + DRAM_VENDOR_MR6) >> DRAM_VENDOR_SHIFT) &
816		DRAM_VENDOR_MASK;
817	mr7 = (readl_relaxed(info + DRAM_VENDOR_MR7) >> DRAM_VENDOR_SHIFT) &
818		DRAM_VENDOR_MASK;
819	mr8 = (readl_relaxed(info + DRAM_VENDOR_MR8) >> DRAM_VENDOR_SHIFT) &
820		DRAM_VENDOR_MASK;
821	err = readl_relaxed(info + DRAM_VENDOR_ERROR) & DRAM_VENDOR_MASK;
822
823	return sprintf(buf, "%#x %#x %#x %#x %#x\n", mr5, mr6, mr7, mr8, err);
824}
825
826static ssize_t show_dram(struct device *dev, struct device_attribute *devattr,
827			 char *buf)
828{
829	u32 response[MSG_FIELD_MAX];
830	struct brcmstb_dpfe_priv *priv;
831	ssize_t ret;
832	u32 mr4, mr5, mr6, mr7, mr8, err;
833
834	priv = dev_get_drvdata(dev);
835	ret = generic_show(DPFE_CMD_GET_REFRESH, response, priv, buf);
836	if (ret)
837		return ret;
838
839	mr4 = response[MSG_ARG0 + 0] & DRAM_INFO_MR4_MASK;
840	mr5 = response[MSG_ARG0 + 1] & DRAM_DDR_INFO_MASK;
841	mr6 = response[MSG_ARG0 + 2] & DRAM_DDR_INFO_MASK;
842	mr7 = response[MSG_ARG0 + 3] & DRAM_DDR_INFO_MASK;
843	mr8 = response[MSG_ARG0 + 4] & DRAM_DDR_INFO_MASK;
844	err = response[MSG_ARG0 + 5] & DRAM_DDR_INFO_MASK;
845
846	return sprintf(buf, "%#x %#x %#x %#x %#x %#x\n", mr4, mr5, mr6, mr7,
847			mr8, err);
848}
849
850static int brcmstb_dpfe_resume(struct platform_device *pdev)
851{
852	struct brcmstb_dpfe_priv *priv = platform_get_drvdata(pdev);
853
854	return brcmstb_dpfe_download_firmware(priv);
855}
856
857static int brcmstb_dpfe_probe(struct platform_device *pdev)
858{
859	struct device *dev = &pdev->dev;
860	struct brcmstb_dpfe_priv *priv;
 
 
861	int ret;
862
863	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
864	if (!priv)
865		return -ENOMEM;
866
867	priv->dev = dev;
868
869	mutex_init(&priv->lock);
870	platform_set_drvdata(pdev, priv);
871
872	priv->regs = devm_platform_ioremap_resource_byname(pdev, "dpfe-cpu");
 
873	if (IS_ERR(priv->regs)) {
874		dev_err(dev, "couldn't map DCPU registers\n");
875		return -ENODEV;
876	}
877
878	priv->dmem = devm_platform_ioremap_resource_byname(pdev, "dpfe-dmem");
 
879	if (IS_ERR(priv->dmem)) {
880		dev_err(dev, "Couldn't map DCPU data memory\n");
881		return -ENOENT;
882	}
883
884	priv->imem = devm_platform_ioremap_resource_byname(pdev, "dpfe-imem");
 
885	if (IS_ERR(priv->imem)) {
886		dev_err(dev, "Couldn't map DCPU instruction memory\n");
887		return -ENOENT;
888	}
889
890	priv->dpfe_api = of_device_get_match_data(dev);
891	if (unlikely(!priv->dpfe_api)) {
892		/*
893		 * It should be impossible to end up here, but to be safe we
894		 * check anyway.
895		 */
896		dev_err(dev, "Couldn't determine API\n");
897		return -ENOENT;
898	}
899
900	ret = brcmstb_dpfe_download_firmware(priv);
901	if (ret)
902		return dev_err_probe(dev, ret, "Couldn't download firmware\n");
 
 
903
904	ret = sysfs_create_groups(&pdev->dev.kobj, priv->dpfe_api->sysfs_attrs);
905	if (!ret)
906		dev_info(dev, "registered with API v%d.\n",
907			 priv->dpfe_api->version);
908
909	return ret;
910}
911
912static void brcmstb_dpfe_remove(struct platform_device *pdev)
913{
914	struct brcmstb_dpfe_priv *priv = dev_get_drvdata(&pdev->dev);
915
916	sysfs_remove_groups(&pdev->dev.kobj, priv->dpfe_api->sysfs_attrs);
 
 
917}
918
919static const struct of_device_id brcmstb_dpfe_of_match[] = {
920	/* Use legacy API v2 for a select number of chips */
921	{ .compatible = "brcm,bcm7268-dpfe-cpu", .data = &dpfe_api_old_v2 },
922	{ .compatible = "brcm,bcm7271-dpfe-cpu", .data = &dpfe_api_old_v2 },
923	{ .compatible = "brcm,bcm7278-dpfe-cpu", .data = &dpfe_api_old_v2 },
924	{ .compatible = "brcm,bcm7211-dpfe-cpu", .data = &dpfe_api_new_v2 },
925	/* API v3 is the default going forward */
926	{ .compatible = "brcm,dpfe-cpu", .data = &dpfe_api_v3 },
927	{}
928};
929MODULE_DEVICE_TABLE(of, brcmstb_dpfe_of_match);
930
931static struct platform_driver brcmstb_dpfe_driver = {
932	.driver	= {
933		.name = DRVNAME,
934		.of_match_table = brcmstb_dpfe_of_match,
935	},
936	.probe = brcmstb_dpfe_probe,
937	.remove_new = brcmstb_dpfe_remove,
938	.resume = brcmstb_dpfe_resume,
939};
940
941module_platform_driver(brcmstb_dpfe_driver);
942
943MODULE_AUTHOR("Markus Mayer <mmayer@broadcom.com>");
944MODULE_DESCRIPTION("BRCMSTB DDR PHY Front End Driver");
945MODULE_LICENSE("GPL");
v5.4
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * DDR PHY Front End (DPFE) driver for Broadcom set top box SoCs
  4 *
  5 * Copyright (c) 2017 Broadcom
  6 */
  7
  8/*
  9 * This driver provides access to the DPFE interface of Broadcom STB SoCs.
 10 * The firmware running on the DCPU inside the DDR PHY can provide current
 11 * information about the system's RAM, for instance the DRAM refresh rate.
 12 * This can be used as an indirect indicator for the DRAM's temperature.
 13 * Slower refresh rate means cooler RAM, higher refresh rate means hotter
 14 * RAM.
 15 *
 16 * Throughout the driver, we use readl_relaxed() and writel_relaxed(), which
 17 * already contain the appropriate le32_to_cpu()/cpu_to_le32() calls.
 18 *
 19 * Note regarding the loading of the firmware image: we use be32_to_cpu()
 20 * and le_32_to_cpu(), so we can support the following four cases:
 21 *     - LE kernel + LE firmware image (the most common case)
 22 *     - LE kernel + BE firmware image
 23 *     - BE kernel + LE firmware image
 24 *     - BE kernel + BE firmware image
 25 *
 26 * The DPCU always runs in big endian mode. The firwmare image, however, can
 27 * be in either format. Also, communication between host CPU and DCPU is
 28 * always in little endian.
 29 */
 30
 31#include <linux/delay.h>
 32#include <linux/firmware.h>
 33#include <linux/io.h>
 34#include <linux/module.h>
 35#include <linux/of_address.h>
 36#include <linux/of_device.h>
 37#include <linux/platform_device.h>
 38
 39#define DRVNAME			"brcmstb-dpfe"
 40
 41/* DCPU register offsets */
 42#define REG_DCPU_RESET		0x0
 43#define REG_TO_DCPU_MBOX	0x10
 44#define REG_TO_HOST_MBOX	0x14
 45
 46/* Macros to process offsets returned by the DCPU */
 47#define DRAM_MSG_ADDR_OFFSET	0x0
 48#define DRAM_MSG_TYPE_OFFSET	0x1c
 49#define DRAM_MSG_ADDR_MASK	((1UL << DRAM_MSG_TYPE_OFFSET) - 1)
 50#define DRAM_MSG_TYPE_MASK	((1UL << \
 51				 (BITS_PER_LONG - DRAM_MSG_TYPE_OFFSET)) - 1)
 52
 53/* Message RAM */
 54#define DCPU_MSG_RAM_START	0x100
 55#define DCPU_MSG_RAM(x)		(DCPU_MSG_RAM_START + (x) * sizeof(u32))
 56
 57/* DRAM Info Offsets & Masks */
 58#define DRAM_INFO_INTERVAL	0x0
 59#define DRAM_INFO_MR4		0x4
 60#define DRAM_INFO_ERROR		0x8
 61#define DRAM_INFO_MR4_MASK	0xff
 62#define DRAM_INFO_MR4_SHIFT	24	/* We need to look at byte 3 */
 63
 64/* DRAM MR4 Offsets & Masks */
 65#define DRAM_MR4_REFRESH	0x0	/* Refresh rate */
 66#define DRAM_MR4_SR_ABORT	0x3	/* Self Refresh Abort */
 67#define DRAM_MR4_PPRE		0x4	/* Post-package repair entry/exit */
 68#define DRAM_MR4_TH_OFFS	0x5	/* Thermal Offset; vendor specific */
 69#define DRAM_MR4_TUF		0x7	/* Temperature Update Flag */
 70
 71#define DRAM_MR4_REFRESH_MASK	0x7
 72#define DRAM_MR4_SR_ABORT_MASK	0x1
 73#define DRAM_MR4_PPRE_MASK	0x1
 74#define DRAM_MR4_TH_OFFS_MASK	0x3
 75#define DRAM_MR4_TUF_MASK	0x1
 76
 77/* DRAM Vendor Offsets & Masks (API v2) */
 78#define DRAM_VENDOR_MR5		0x0
 79#define DRAM_VENDOR_MR6		0x4
 80#define DRAM_VENDOR_MR7		0x8
 81#define DRAM_VENDOR_MR8		0xc
 82#define DRAM_VENDOR_ERROR	0x10
 83#define DRAM_VENDOR_MASK	0xff
 84#define DRAM_VENDOR_SHIFT	24	/* We need to look at byte 3 */
 85
 86/* DRAM Information Offsets & Masks (API v3) */
 87#define DRAM_DDR_INFO_MR4	0x0
 88#define DRAM_DDR_INFO_MR5	0x4
 89#define DRAM_DDR_INFO_MR6	0x8
 90#define DRAM_DDR_INFO_MR7	0xc
 91#define DRAM_DDR_INFO_MR8	0x10
 92#define DRAM_DDR_INFO_ERROR	0x14
 93#define DRAM_DDR_INFO_MASK	0xff
 94
 95/* Reset register bits & masks */
 96#define DCPU_RESET_SHIFT	0x0
 97#define DCPU_RESET_MASK		0x1
 98#define DCPU_CLK_DISABLE_SHIFT	0x2
 99
100/* DCPU return codes */
101#define DCPU_RET_ERROR_BIT	BIT(31)
102#define DCPU_RET_SUCCESS	0x1
103#define DCPU_RET_ERR_HEADER	(DCPU_RET_ERROR_BIT | BIT(0))
104#define DCPU_RET_ERR_INVAL	(DCPU_RET_ERROR_BIT | BIT(1))
105#define DCPU_RET_ERR_CHKSUM	(DCPU_RET_ERROR_BIT | BIT(2))
106#define DCPU_RET_ERR_COMMAND	(DCPU_RET_ERROR_BIT | BIT(3))
107/* This error code is not firmware defined and only used in the driver. */
108#define DCPU_RET_ERR_TIMEDOUT	(DCPU_RET_ERROR_BIT | BIT(4))
109
110/* Firmware magic */
111#define DPFE_BE_MAGIC		0xfe1010fe
112#define DPFE_LE_MAGIC		0xfe0101fe
113
114/* Error codes */
115#define ERR_INVALID_MAGIC	-1
116#define ERR_INVALID_SIZE	-2
117#define ERR_INVALID_CHKSUM	-3
118
119/* Message types */
120#define DPFE_MSG_TYPE_COMMAND	1
121#define DPFE_MSG_TYPE_RESPONSE	2
122
123#define DELAY_LOOP_MAX		1000
124
125enum dpfe_msg_fields {
126	MSG_HEADER,
127	MSG_COMMAND,
128	MSG_ARG_COUNT,
129	MSG_ARG0,
130	MSG_CHKSUM,
131	MSG_FIELD_MAX	= 16 /* Max number of arguments */
132};
133
134enum dpfe_commands {
135	DPFE_CMD_GET_INFO,
136	DPFE_CMD_GET_REFRESH,
137	DPFE_CMD_GET_VENDOR,
138	DPFE_CMD_MAX /* Last entry */
139};
140
141/*
142 * Format of the binary firmware file:
143 *
144 *   entry
145 *      0    header
146 *              value:  0xfe0101fe  <== little endian
147 *                      0xfe1010fe  <== big endian
148 *      1    sequence:
149 *              [31:16] total segments on this build
150 *              [15:0]  this segment sequence.
151 *      2    FW version
152 *      3    IMEM byte size
153 *      4    DMEM byte size
154 *           IMEM
155 *           DMEM
156 *      last checksum ==> sum of everything
157 */
158struct dpfe_firmware_header {
159	u32 magic;
160	u32 sequence;
161	u32 version;
162	u32 imem_size;
163	u32 dmem_size;
164};
165
166/* Things we only need during initialization. */
167struct init_data {
168	unsigned int dmem_len;
169	unsigned int imem_len;
170	unsigned int chksum;
171	bool is_big_endian;
172};
173
174/* API version and corresponding commands */
175struct dpfe_api {
176	int version;
177	const char *fw_name;
178	const struct attribute_group **sysfs_attrs;
179	u32 command[DPFE_CMD_MAX][MSG_FIELD_MAX];
180};
181
182/* Things we need for as long as we are active. */
183struct private_data {
184	void __iomem *regs;
185	void __iomem *dmem;
186	void __iomem *imem;
187	struct device *dev;
188	const struct dpfe_api *dpfe_api;
189	struct mutex lock;
190};
191
192static const char *error_text[] = {
193	"Success", "Header code incorrect", "Unknown command or argument",
194	"Incorrect checksum", "Malformed command", "Timed out",
195};
196
197/*
198 * Forward declaration of our sysfs attribute functions, so we can declare the
199 * attribute data structures early.
200 */
201static ssize_t show_info(struct device *, struct device_attribute *, char *);
202static ssize_t show_refresh(struct device *, struct device_attribute *, char *);
203static ssize_t store_refresh(struct device *, struct device_attribute *,
204			  const char *, size_t);
205static ssize_t show_vendor(struct device *, struct device_attribute *, char *);
206static ssize_t show_dram(struct device *, struct device_attribute *, char *);
207
208/*
209 * Declare our attributes early, so they can be referenced in the API data
210 * structure. We need to do this, because the attributes depend on the API
211 * version.
212 */
213static DEVICE_ATTR(dpfe_info, 0444, show_info, NULL);
214static DEVICE_ATTR(dpfe_refresh, 0644, show_refresh, store_refresh);
215static DEVICE_ATTR(dpfe_vendor, 0444, show_vendor, NULL);
216static DEVICE_ATTR(dpfe_dram, 0444, show_dram, NULL);
217
218/* API v2 sysfs attributes */
219static struct attribute *dpfe_v2_attrs[] = {
220	&dev_attr_dpfe_info.attr,
221	&dev_attr_dpfe_refresh.attr,
222	&dev_attr_dpfe_vendor.attr,
223	NULL
224};
225ATTRIBUTE_GROUPS(dpfe_v2);
226
227/* API v3 sysfs attributes */
228static struct attribute *dpfe_v3_attrs[] = {
229	&dev_attr_dpfe_info.attr,
230	&dev_attr_dpfe_dram.attr,
231	NULL
232};
233ATTRIBUTE_GROUPS(dpfe_v3);
234
235/* API v2 firmware commands */
236static const struct dpfe_api dpfe_api_v2 = {
237	.version = 2,
 
 
 
 
238	.fw_name = "dpfe.bin",
239	.sysfs_attrs = dpfe_v2_groups,
240	.command = {
241		[DPFE_CMD_GET_INFO] = {
242			[MSG_HEADER] = DPFE_MSG_TYPE_COMMAND,
243			[MSG_COMMAND] = 1,
244			[MSG_ARG_COUNT] = 1,
245			[MSG_ARG0] = 1,
246			[MSG_CHKSUM] = 4,
247		},
248		[DPFE_CMD_GET_REFRESH] = {
249			[MSG_HEADER] = DPFE_MSG_TYPE_COMMAND,
250			[MSG_COMMAND] = 2,
251			[MSG_ARG_COUNT] = 1,
252			[MSG_ARG0] = 1,
253			[MSG_CHKSUM] = 5,
254		},
255		[DPFE_CMD_GET_VENDOR] = {
256			[MSG_HEADER] = DPFE_MSG_TYPE_COMMAND,
257			[MSG_COMMAND] = 2,
258			[MSG_ARG_COUNT] = 1,
259			[MSG_ARG0] = 2,
260			[MSG_CHKSUM] = 6,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
261		},
262	}
263};
264
265/* API v3 firmware commands */
266static const struct dpfe_api dpfe_api_v3 = {
267	.version = 3,
268	.fw_name = NULL, /* We expect the firmware to have been downloaded! */
269	.sysfs_attrs = dpfe_v3_groups,
270	.command = {
271		[DPFE_CMD_GET_INFO] = {
272			[MSG_HEADER] = DPFE_MSG_TYPE_COMMAND,
273			[MSG_COMMAND] = 0x0101,
274			[MSG_ARG_COUNT] = 1,
275			[MSG_ARG0] = 1,
276			[MSG_CHKSUM] = 0x104,
277		},
278		[DPFE_CMD_GET_REFRESH] = {
279			[MSG_HEADER] = DPFE_MSG_TYPE_COMMAND,
280			[MSG_COMMAND] = 0x0202,
281			[MSG_ARG_COUNT] = 0,
282			/*
283			 * This is a bit ugly. Without arguments, the checksum
284			 * follows right after the argument count and not at
285			 * offset MSG_CHKSUM.
286			 */
287			[MSG_ARG0] = 0x203,
288		},
289		/* There's no GET_VENDOR command in API v3. */
290	},
291};
292
293static bool is_dcpu_enabled(void __iomem *regs)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
294{
295	u32 val;
296
297	val = readl_relaxed(regs + REG_DCPU_RESET);
 
 
298
299	return !(val & DCPU_RESET_MASK);
300}
301
302static void __disable_dcpu(void __iomem *regs)
303{
304	u32 val;
305
306	if (!is_dcpu_enabled(regs))
307		return;
308
 
 
309	/* Put DCPU in reset if it's running. */
310	val = readl_relaxed(regs + REG_DCPU_RESET);
311	val |= (1 << DCPU_RESET_SHIFT);
312	writel_relaxed(val, regs + REG_DCPU_RESET);
 
 
313}
314
315static void __enable_dcpu(void __iomem *regs)
316{
 
317	u32 val;
318
 
 
319	/* Clear mailbox registers. */
320	writel_relaxed(0, regs + REG_TO_DCPU_MBOX);
321	writel_relaxed(0, regs + REG_TO_HOST_MBOX);
322
323	/* Disable DCPU clock gating */
324	val = readl_relaxed(regs + REG_DCPU_RESET);
325	val &= ~(1 << DCPU_CLK_DISABLE_SHIFT);
326	writel_relaxed(val, regs + REG_DCPU_RESET);
327
328	/* Take DCPU out of reset */
329	val = readl_relaxed(regs + REG_DCPU_RESET);
330	val &= ~(1 << DCPU_RESET_SHIFT);
331	writel_relaxed(val, regs + REG_DCPU_RESET);
 
 
332}
333
334static unsigned int get_msg_chksum(const u32 msg[], unsigned int max)
335{
336	unsigned int sum = 0;
337	unsigned int i;
338
339	/* Don't include the last field in the checksum. */
340	for (i = 0; i < max; i++)
341		sum += msg[i];
342
343	return sum;
344}
345
346static void __iomem *get_msg_ptr(struct private_data *priv, u32 response,
347				 char *buf, ssize_t *size)
348{
349	unsigned int msg_type;
350	unsigned int offset;
351	void __iomem *ptr = NULL;
352
353	/* There is no need to use this function for API v3 or later. */
354	if (unlikely(priv->dpfe_api->version >= 3)) {
355		return NULL;
356	}
357
358	msg_type = (response >> DRAM_MSG_TYPE_OFFSET) & DRAM_MSG_TYPE_MASK;
359	offset = (response >> DRAM_MSG_ADDR_OFFSET) & DRAM_MSG_ADDR_MASK;
360
361	/*
362	 * msg_type == 1: the offset is relative to the message RAM
363	 * msg_type == 0: the offset is relative to the data RAM (this is the
364	 *                previous way of passing data)
365	 * msg_type is anything else: there's critical hardware problem
366	 */
367	switch (msg_type) {
368	case 1:
369		ptr = priv->regs + DCPU_MSG_RAM_START + offset;
370		break;
371	case 0:
372		ptr = priv->dmem + offset;
373		break;
374	default:
375		dev_emerg(priv->dev, "invalid message reply from DCPU: %#x\n",
376			response);
377		if (buf && size)
378			*size = sprintf(buf,
379				"FATAL: communication error with DCPU\n");
380	}
381
382	return ptr;
383}
384
385static void __finalize_command(struct private_data *priv)
386{
387	unsigned int release_mbox;
388
389	/*
390	 * It depends on the API version which MBOX register we have to write to
391	 * to signal we are done.
392	 */
393	release_mbox = (priv->dpfe_api->version < 3)
394			? REG_TO_HOST_MBOX : REG_TO_DCPU_MBOX;
395	writel_relaxed(0, priv->regs + release_mbox);
396}
397
398static int __send_command(struct private_data *priv, unsigned int cmd,
399			  u32 result[])
400{
401	const u32 *msg = priv->dpfe_api->command[cmd];
402	void __iomem *regs = priv->regs;
403	unsigned int i, chksum, chksum_idx;
 
404	int ret = 0;
405	u32 resp;
406
407	if (cmd >= DPFE_CMD_MAX)
408		return -1;
409
 
 
410	mutex_lock(&priv->lock);
411
412	/* Wait for DCPU to become ready */
413	for (i = 0; i < DELAY_LOOP_MAX; i++) {
414		resp = readl_relaxed(regs + REG_TO_HOST_MBOX);
415		if (resp == 0)
416			break;
417		msleep(1);
418	}
419	if (resp != 0) {
420		mutex_unlock(&priv->lock);
421		return -ETIMEDOUT;
422	}
423
 
 
 
 
424	/* Write command and arguments to message area */
425	for (i = 0; i < MSG_FIELD_MAX; i++)
426		writel_relaxed(msg[i], regs + DCPU_MSG_RAM(i));
 
 
 
 
427
428	/* Tell DCPU there is a command waiting */
429	writel_relaxed(1, regs + REG_TO_DCPU_MBOX);
430
431	/* Wait for DCPU to process the command */
432	for (i = 0; i < DELAY_LOOP_MAX; i++) {
433		/* Read response code */
434		resp = readl_relaxed(regs + REG_TO_HOST_MBOX);
435		if (resp > 0)
436			break;
437		msleep(1);
438	}
439
440	if (i == DELAY_LOOP_MAX) {
441		resp = (DCPU_RET_ERR_TIMEDOUT & ~DCPU_RET_ERROR_BIT);
442		ret = -ffs(resp);
443	} else {
444		/* Read response data */
445		for (i = 0; i < MSG_FIELD_MAX; i++)
446			result[i] = readl_relaxed(regs + DCPU_MSG_RAM(i));
447		chksum_idx = result[MSG_ARG_COUNT] + MSG_ARG_COUNT + 1;
448	}
449
450	/* Tell DCPU we are done */
451	__finalize_command(priv);
452
453	mutex_unlock(&priv->lock);
454
455	if (ret)
456		return ret;
457
458	/* Verify response */
459	chksum = get_msg_chksum(result, chksum_idx);
460	if (chksum != result[chksum_idx])
461		resp = DCPU_RET_ERR_CHKSUM;
462
463	if (resp != DCPU_RET_SUCCESS) {
464		resp &= ~DCPU_RET_ERROR_BIT;
465		ret = -ffs(resp);
466	}
467
468	return ret;
469}
470
471/* Ensure that the firmware file loaded meets all the requirements. */
472static int __verify_firmware(struct init_data *init,
473			     const struct firmware *fw)
474{
475	const struct dpfe_firmware_header *header = (void *)fw->data;
476	unsigned int dmem_size, imem_size, total_size;
477	bool is_big_endian = false;
478	const u32 *chksum_ptr;
479
480	if (header->magic == DPFE_BE_MAGIC)
481		is_big_endian = true;
482	else if (header->magic != DPFE_LE_MAGIC)
483		return ERR_INVALID_MAGIC;
484
485	if (is_big_endian) {
486		dmem_size = be32_to_cpu(header->dmem_size);
487		imem_size = be32_to_cpu(header->imem_size);
488	} else {
489		dmem_size = le32_to_cpu(header->dmem_size);
490		imem_size = le32_to_cpu(header->imem_size);
491	}
492
493	/* Data and instruction sections are 32 bit words. */
494	if ((dmem_size % sizeof(u32)) != 0 || (imem_size % sizeof(u32)) != 0)
495		return ERR_INVALID_SIZE;
496
497	/*
498	 * The header + the data section + the instruction section + the
499	 * checksum must be equal to the total firmware size.
500	 */
501	total_size = dmem_size + imem_size + sizeof(*header) +
502		sizeof(*chksum_ptr);
503	if (total_size != fw->size)
504		return ERR_INVALID_SIZE;
505
506	/* The checksum comes at the very end. */
507	chksum_ptr = (void *)fw->data + sizeof(*header) + dmem_size + imem_size;
508
509	init->is_big_endian = is_big_endian;
510	init->dmem_len = dmem_size;
511	init->imem_len = imem_size;
512	init->chksum = (is_big_endian)
513		? be32_to_cpu(*chksum_ptr) : le32_to_cpu(*chksum_ptr);
514
515	return 0;
516}
517
518/* Verify checksum by reading back the firmware from co-processor RAM. */
519static int __verify_fw_checksum(struct init_data *init,
520				struct private_data *priv,
521				const struct dpfe_firmware_header *header,
522				u32 checksum)
523{
524	u32 magic, sequence, version, sum;
525	u32 __iomem *dmem = priv->dmem;
526	u32 __iomem *imem = priv->imem;
527	unsigned int i;
528
529	if (init->is_big_endian) {
530		magic = be32_to_cpu(header->magic);
531		sequence = be32_to_cpu(header->sequence);
532		version = be32_to_cpu(header->version);
533	} else {
534		magic = le32_to_cpu(header->magic);
535		sequence = le32_to_cpu(header->sequence);
536		version = le32_to_cpu(header->version);
537	}
538
539	sum = magic + sequence + version + init->dmem_len + init->imem_len;
540
541	for (i = 0; i < init->dmem_len / sizeof(u32); i++)
542		sum += readl_relaxed(dmem + i);
543
544	for (i = 0; i < init->imem_len / sizeof(u32); i++)
545		sum += readl_relaxed(imem + i);
546
547	return (sum == checksum) ? 0 : -1;
548}
549
550static int __write_firmware(u32 __iomem *mem, const u32 *fw,
551			    unsigned int size, bool is_big_endian)
552{
553	unsigned int i;
554
555	/* Convert size to 32-bit words. */
556	size /= sizeof(u32);
557
558	/* It is recommended to clear the firmware area first. */
559	for (i = 0; i < size; i++)
560		writel_relaxed(0, mem + i);
561
562	/* Now copy it. */
563	if (is_big_endian) {
564		for (i = 0; i < size; i++)
565			writel_relaxed(be32_to_cpu(fw[i]), mem + i);
566	} else {
567		for (i = 0; i < size; i++)
568			writel_relaxed(le32_to_cpu(fw[i]), mem + i);
569	}
570
571	return 0;
572}
573
574static int brcmstb_dpfe_download_firmware(struct platform_device *pdev,
575					  struct init_data *init)
576{
577	const struct dpfe_firmware_header *header;
578	unsigned int dmem_size, imem_size;
579	struct device *dev = &pdev->dev;
580	bool is_big_endian = false;
581	struct private_data *priv;
582	const struct firmware *fw;
583	const u32 *dmem, *imem;
 
584	const void *fw_blob;
585	int ret;
586
587	priv = platform_get_drvdata(pdev);
588
589	/*
590	 * Skip downloading the firmware if the DCPU is already running and
591	 * responding to commands.
592	 */
593	if (is_dcpu_enabled(priv->regs)) {
594		u32 response[MSG_FIELD_MAX];
595
596		ret = __send_command(priv, DPFE_CMD_GET_INFO, response);
597		if (!ret)
598			return 0;
599	}
600
601	/*
602	 * If the firmware filename is NULL it means the boot firmware has to
603	 * download the DCPU firmware for us. If that didn't work, we have to
604	 * bail, since downloading it ourselves wouldn't work either.
605	 */
606	if (!priv->dpfe_api->fw_name)
607		return -ENODEV;
608
609	ret = request_firmware(&fw, priv->dpfe_api->fw_name, dev);
610	/* request_firmware() prints its own error messages. */
 
 
 
611	if (ret)
612		return ret;
613
614	ret = __verify_firmware(init, fw);
615	if (ret)
616		return -EFAULT;
 
 
617
618	__disable_dcpu(priv->regs);
619
620	is_big_endian = init->is_big_endian;
621	dmem_size = init->dmem_len;
622	imem_size = init->imem_len;
623
624	/* At the beginning of the firmware blob is a header. */
625	header = (struct dpfe_firmware_header *)fw->data;
626	/* Void pointer to the beginning of the actual firmware. */
627	fw_blob = fw->data + sizeof(*header);
628	/* IMEM comes right after the header. */
629	imem = fw_blob;
630	/* DMEM follows after IMEM. */
631	dmem = fw_blob + imem_size;
632
633	ret = __write_firmware(priv->dmem, dmem, dmem_size, is_big_endian);
634	if (ret)
635		return ret;
636	ret = __write_firmware(priv->imem, imem, imem_size, is_big_endian);
637	if (ret)
638		return ret;
639
640	ret = __verify_fw_checksum(init, priv, header, init->chksum);
641	if (ret)
642		return ret;
643
644	__enable_dcpu(priv->regs);
645
646	return 0;
 
 
647}
648
649static ssize_t generic_show(unsigned int command, u32 response[],
650			    struct private_data *priv, char *buf)
651{
652	int ret;
653
654	if (!priv)
655		return sprintf(buf, "ERROR: driver private data not set\n");
656
657	ret = __send_command(priv, command, response);
658	if (ret < 0)
659		return sprintf(buf, "ERROR: %s\n", error_text[-ret]);
660
661	return 0;
662}
663
664static ssize_t show_info(struct device *dev, struct device_attribute *devattr,
665			 char *buf)
666{
667	u32 response[MSG_FIELD_MAX];
668	struct private_data *priv;
669	unsigned int info;
670	ssize_t ret;
671
672	priv = dev_get_drvdata(dev);
673	ret = generic_show(DPFE_CMD_GET_INFO, response, priv, buf);
674	if (ret)
675		return ret;
676
677	info = response[MSG_ARG0];
678
679	return sprintf(buf, "%u.%u.%u.%u\n",
680		       (info >> 24) & 0xff,
681		       (info >> 16) & 0xff,
682		       (info >> 8) & 0xff,
683		       info & 0xff);
684}
685
686static ssize_t show_refresh(struct device *dev,
687			    struct device_attribute *devattr, char *buf)
688{
689	u32 response[MSG_FIELD_MAX];
690	void __iomem *info;
691	struct private_data *priv;
692	u8 refresh, sr_abort, ppre, thermal_offs, tuf;
693	u32 mr4;
694	ssize_t ret;
695
696	priv = dev_get_drvdata(dev);
697	ret = generic_show(DPFE_CMD_GET_REFRESH, response, priv, buf);
698	if (ret)
699		return ret;
700
701	info = get_msg_ptr(priv, response[MSG_ARG0], buf, &ret);
702	if (!info)
703		return ret;
704
705	mr4 = (readl_relaxed(info + DRAM_INFO_MR4) >> DRAM_INFO_MR4_SHIFT) &
706	       DRAM_INFO_MR4_MASK;
707
708	refresh = (mr4 >> DRAM_MR4_REFRESH) & DRAM_MR4_REFRESH_MASK;
709	sr_abort = (mr4 >> DRAM_MR4_SR_ABORT) & DRAM_MR4_SR_ABORT_MASK;
710	ppre = (mr4 >> DRAM_MR4_PPRE) & DRAM_MR4_PPRE_MASK;
711	thermal_offs = (mr4 >> DRAM_MR4_TH_OFFS) & DRAM_MR4_TH_OFFS_MASK;
712	tuf = (mr4 >> DRAM_MR4_TUF) & DRAM_MR4_TUF_MASK;
713
714	return sprintf(buf, "%#x %#x %#x %#x %#x %#x %#x\n",
715		       readl_relaxed(info + DRAM_INFO_INTERVAL),
716		       refresh, sr_abort, ppre, thermal_offs, tuf,
717		       readl_relaxed(info + DRAM_INFO_ERROR));
718}
719
720static ssize_t store_refresh(struct device *dev, struct device_attribute *attr,
721			  const char *buf, size_t count)
722{
723	u32 response[MSG_FIELD_MAX];
724	struct private_data *priv;
725	void __iomem *info;
726	unsigned long val;
727	int ret;
728
729	if (kstrtoul(buf, 0, &val) < 0)
730		return -EINVAL;
731
732	priv = dev_get_drvdata(dev);
733	ret = __send_command(priv, DPFE_CMD_GET_REFRESH, response);
734	if (ret)
735		return ret;
736
737	info = get_msg_ptr(priv, response[MSG_ARG0], NULL, NULL);
738	if (!info)
739		return -EIO;
740
741	writel_relaxed(val, info + DRAM_INFO_INTERVAL);
742
743	return count;
744}
745
746static ssize_t show_vendor(struct device *dev, struct device_attribute *devattr,
747			   char *buf)
748{
749	u32 response[MSG_FIELD_MAX];
750	struct private_data *priv;
751	void __iomem *info;
752	ssize_t ret;
753	u32 mr5, mr6, mr7, mr8, err;
754
755	priv = dev_get_drvdata(dev);
756	ret = generic_show(DPFE_CMD_GET_VENDOR, response, priv, buf);
757	if (ret)
758		return ret;
759
760	info = get_msg_ptr(priv, response[MSG_ARG0], buf, &ret);
761	if (!info)
762		return ret;
763
764	mr5 = (readl_relaxed(info + DRAM_VENDOR_MR5) >> DRAM_VENDOR_SHIFT) &
765		DRAM_VENDOR_MASK;
766	mr6 = (readl_relaxed(info + DRAM_VENDOR_MR6) >> DRAM_VENDOR_SHIFT) &
767		DRAM_VENDOR_MASK;
768	mr7 = (readl_relaxed(info + DRAM_VENDOR_MR7) >> DRAM_VENDOR_SHIFT) &
769		DRAM_VENDOR_MASK;
770	mr8 = (readl_relaxed(info + DRAM_VENDOR_MR8) >> DRAM_VENDOR_SHIFT) &
771		DRAM_VENDOR_MASK;
772	err = readl_relaxed(info + DRAM_VENDOR_ERROR) & DRAM_VENDOR_MASK;
773
774	return sprintf(buf, "%#x %#x %#x %#x %#x\n", mr5, mr6, mr7, mr8, err);
775}
776
777static ssize_t show_dram(struct device *dev, struct device_attribute *devattr,
778			 char *buf)
779{
780	u32 response[MSG_FIELD_MAX];
781	struct private_data *priv;
782	ssize_t ret;
783	u32 mr4, mr5, mr6, mr7, mr8, err;
784
785	priv = dev_get_drvdata(dev);
786	ret = generic_show(DPFE_CMD_GET_REFRESH, response, priv, buf);
787	if (ret)
788		return ret;
789
790	mr4 = response[MSG_ARG0 + 0] & DRAM_INFO_MR4_MASK;
791	mr5 = response[MSG_ARG0 + 1] & DRAM_DDR_INFO_MASK;
792	mr6 = response[MSG_ARG0 + 2] & DRAM_DDR_INFO_MASK;
793	mr7 = response[MSG_ARG0 + 3] & DRAM_DDR_INFO_MASK;
794	mr8 = response[MSG_ARG0 + 4] & DRAM_DDR_INFO_MASK;
795	err = response[MSG_ARG0 + 5] & DRAM_DDR_INFO_MASK;
796
797	return sprintf(buf, "%#x %#x %#x %#x %#x %#x\n", mr4, mr5, mr6, mr7,
798			mr8, err);
799}
800
801static int brcmstb_dpfe_resume(struct platform_device *pdev)
802{
803	struct init_data init;
804
805	return brcmstb_dpfe_download_firmware(pdev, &init);
806}
807
808static int brcmstb_dpfe_probe(struct platform_device *pdev)
809{
810	struct device *dev = &pdev->dev;
811	struct private_data *priv;
812	struct init_data init;
813	struct resource *res;
814	int ret;
815
816	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
817	if (!priv)
818		return -ENOMEM;
819
 
 
820	mutex_init(&priv->lock);
821	platform_set_drvdata(pdev, priv);
822
823	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dpfe-cpu");
824	priv->regs = devm_ioremap_resource(dev, res);
825	if (IS_ERR(priv->regs)) {
826		dev_err(dev, "couldn't map DCPU registers\n");
827		return -ENODEV;
828	}
829
830	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dpfe-dmem");
831	priv->dmem = devm_ioremap_resource(dev, res);
832	if (IS_ERR(priv->dmem)) {
833		dev_err(dev, "Couldn't map DCPU data memory\n");
834		return -ENOENT;
835	}
836
837	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dpfe-imem");
838	priv->imem = devm_ioremap_resource(dev, res);
839	if (IS_ERR(priv->imem)) {
840		dev_err(dev, "Couldn't map DCPU instruction memory\n");
841		return -ENOENT;
842	}
843
844	priv->dpfe_api = of_device_get_match_data(dev);
845	if (unlikely(!priv->dpfe_api)) {
846		/*
847		 * It should be impossible to end up here, but to be safe we
848		 * check anyway.
849		 */
850		dev_err(dev, "Couldn't determine API\n");
851		return -ENOENT;
852	}
853
854	ret = brcmstb_dpfe_download_firmware(pdev, &init);
855	if (ret) {
856		dev_err(dev, "Couldn't download firmware -- %d\n", ret);
857		return ret;
858	}
859
860	ret = sysfs_create_groups(&pdev->dev.kobj, priv->dpfe_api->sysfs_attrs);
861	if (!ret)
862		dev_info(dev, "registered with API v%d.\n",
863			 priv->dpfe_api->version);
864
865	return ret;
866}
867
868static int brcmstb_dpfe_remove(struct platform_device *pdev)
869{
870	struct private_data *priv = dev_get_drvdata(&pdev->dev);
871
872	sysfs_remove_groups(&pdev->dev.kobj, priv->dpfe_api->sysfs_attrs);
873
874	return 0;
875}
876
877static const struct of_device_id brcmstb_dpfe_of_match[] = {
878	/* Use legacy API v2 for a select number of chips */
879	{ .compatible = "brcm,bcm7268-dpfe-cpu", .data = &dpfe_api_v2 },
880	{ .compatible = "brcm,bcm7271-dpfe-cpu", .data = &dpfe_api_v2 },
881	{ .compatible = "brcm,bcm7278-dpfe-cpu", .data = &dpfe_api_v2 },
882	{ .compatible = "brcm,bcm7211-dpfe-cpu", .data = &dpfe_api_v2 },
883	/* API v3 is the default going forward */
884	{ .compatible = "brcm,dpfe-cpu", .data = &dpfe_api_v3 },
885	{}
886};
887MODULE_DEVICE_TABLE(of, brcmstb_dpfe_of_match);
888
889static struct platform_driver brcmstb_dpfe_driver = {
890	.driver	= {
891		.name = DRVNAME,
892		.of_match_table = brcmstb_dpfe_of_match,
893	},
894	.probe = brcmstb_dpfe_probe,
895	.remove	= brcmstb_dpfe_remove,
896	.resume = brcmstb_dpfe_resume,
897};
898
899module_platform_driver(brcmstb_dpfe_driver);
900
901MODULE_AUTHOR("Markus Mayer <mmayer@broadcom.com>");
902MODULE_DESCRIPTION("BRCMSTB DDR PHY Front End Driver");
903MODULE_LICENSE("GPL");