xref: /openbmc/linux/drivers/memory/brcmstb_dpfe.c (revision 5d331b7f)
1 /*
2  * DDR PHY Front End (DPFE) driver for Broadcom set top box SoCs
3  *
4  * Copyright (c) 2017 Broadcom
5  *
6  * Released under the GPLv2 only.
7  * SPDX-License-Identifier: GPL-2.0
8  */
9 
10 /*
11  * This driver provides access to the DPFE interface of Broadcom STB SoCs.
12  * The firmware running on the DCPU inside the DDR PHY can provide current
13  * information about the system's RAM, for instance the DRAM refresh rate.
14  * This can be used as an indirect indicator for the DRAM's temperature.
15  * Slower refresh rate means cooler RAM, higher refresh rate means hotter
16  * RAM.
17  *
18  * Throughout the driver, we use readl_relaxed() and writel_relaxed(), which
19  * already contain the appropriate le32_to_cpu()/cpu_to_le32() calls.
20  *
21  * Note regarding the loading of the firmware image: we use be32_to_cpu()
22  * and le_32_to_cpu(), so we can support the following four cases:
23  *     - LE kernel + LE firmware image (the most common case)
24  *     - LE kernel + BE firmware image
25  *     - BE kernel + LE firmware image
26  *     - BE kernel + BE firmware image
27  *
28  * The DPCU always runs in big endian mode. The firwmare image, however, can
29  * be in either format. Also, communication between host CPU and DCPU is
30  * always in little endian.
31  */
32 
33 #include <linux/delay.h>
34 #include <linux/firmware.h>
35 #include <linux/io.h>
36 #include <linux/module.h>
37 #include <linux/of_address.h>
38 #include <linux/platform_device.h>
39 
40 #define DRVNAME			"brcmstb-dpfe"
41 #define FIRMWARE_NAME		"dpfe.bin"
42 
43 /* DCPU register offsets */
44 #define REG_DCPU_RESET		0x0
45 #define REG_TO_DCPU_MBOX	0x10
46 #define REG_TO_HOST_MBOX	0x14
47 
48 /* Macros to process offsets returned by the DCPU */
49 #define DRAM_MSG_ADDR_OFFSET	0x0
50 #define DRAM_MSG_TYPE_OFFSET	0x1c
51 #define DRAM_MSG_ADDR_MASK	((1UL << DRAM_MSG_TYPE_OFFSET) - 1)
52 #define DRAM_MSG_TYPE_MASK	((1UL << \
53 				 (BITS_PER_LONG - DRAM_MSG_TYPE_OFFSET)) - 1)
54 
55 /* Message RAM */
56 #define DCPU_MSG_RAM_START	0x100
57 #define DCPU_MSG_RAM(x)		(DCPU_MSG_RAM_START + (x) * sizeof(u32))
58 
59 /* DRAM Info Offsets & Masks */
60 #define DRAM_INFO_INTERVAL	0x0
61 #define DRAM_INFO_MR4		0x4
62 #define DRAM_INFO_ERROR		0x8
63 #define DRAM_INFO_MR4_MASK	0xff
64 
65 /* DRAM MR4 Offsets & Masks */
66 #define DRAM_MR4_REFRESH	0x0	/* Refresh rate */
67 #define DRAM_MR4_SR_ABORT	0x3	/* Self Refresh Abort */
68 #define DRAM_MR4_PPRE		0x4	/* Post-package repair entry/exit */
69 #define DRAM_MR4_TH_OFFS	0x5	/* Thermal Offset; vendor specific */
70 #define DRAM_MR4_TUF		0x7	/* Temperature Update Flag */
71 
72 #define DRAM_MR4_REFRESH_MASK	0x7
73 #define DRAM_MR4_SR_ABORT_MASK	0x1
74 #define DRAM_MR4_PPRE_MASK	0x1
75 #define DRAM_MR4_TH_OFFS_MASK	0x3
76 #define DRAM_MR4_TUF_MASK	0x1
77 
78 /* DRAM Vendor Offsets & Masks */
79 #define DRAM_VENDOR_MR5		0x0
80 #define DRAM_VENDOR_MR6		0x4
81 #define DRAM_VENDOR_MR7		0x8
82 #define DRAM_VENDOR_MR8		0xc
83 #define DRAM_VENDOR_ERROR	0x10
84 #define DRAM_VENDOR_MASK	0xff
85 
86 /* Reset register bits & masks */
87 #define DCPU_RESET_SHIFT	0x0
88 #define DCPU_RESET_MASK		0x1
89 #define DCPU_CLK_DISABLE_SHIFT	0x2
90 
91 /* DCPU return codes */
92 #define DCPU_RET_ERROR_BIT	BIT(31)
93 #define DCPU_RET_SUCCESS	0x1
94 #define DCPU_RET_ERR_HEADER	(DCPU_RET_ERROR_BIT | BIT(0))
95 #define DCPU_RET_ERR_INVAL	(DCPU_RET_ERROR_BIT | BIT(1))
96 #define DCPU_RET_ERR_CHKSUM	(DCPU_RET_ERROR_BIT | BIT(2))
97 #define DCPU_RET_ERR_COMMAND	(DCPU_RET_ERROR_BIT | BIT(3))
98 /* This error code is not firmware defined and only used in the driver. */
99 #define DCPU_RET_ERR_TIMEDOUT	(DCPU_RET_ERROR_BIT | BIT(4))
100 
101 /* Firmware magic */
102 #define DPFE_BE_MAGIC		0xfe1010fe
103 #define DPFE_LE_MAGIC		0xfe0101fe
104 
105 /* Error codes */
106 #define ERR_INVALID_MAGIC	-1
107 #define ERR_INVALID_SIZE	-2
108 #define ERR_INVALID_CHKSUM	-3
109 
110 /* Message types */
111 #define DPFE_MSG_TYPE_COMMAND	1
112 #define DPFE_MSG_TYPE_RESPONSE	2
113 
114 #define DELAY_LOOP_MAX		200000
115 
116 enum dpfe_msg_fields {
117 	MSG_HEADER,
118 	MSG_COMMAND,
119 	MSG_ARG_COUNT,
120 	MSG_ARG0,
121 	MSG_CHKSUM,
122 	MSG_FIELD_MAX /* Last entry */
123 };
124 
125 enum dpfe_commands {
126 	DPFE_CMD_GET_INFO,
127 	DPFE_CMD_GET_REFRESH,
128 	DPFE_CMD_GET_VENDOR,
129 	DPFE_CMD_MAX /* Last entry */
130 };
131 
132 struct dpfe_msg {
133 	u32 header;
134 	u32 command;
135 	u32 arg_count;
136 	u32 arg0;
137 	u32 chksum; /* This is the sum of all other entries. */
138 };
139 
140 /*
141  * Format of the binary firmware file:
142  *
143  *   entry
144  *      0    header
145  *              value:  0xfe0101fe  <== little endian
146  *                      0xfe1010fe  <== big endian
147  *      1    sequence:
148  *              [31:16] total segments on this build
149  *              [15:0]  this segment sequence.
150  *      2    FW version
151  *      3    IMEM byte size
152  *      4    DMEM byte size
153  *           IMEM
154  *           DMEM
155  *      last checksum ==> sum of everything
156  */
157 struct dpfe_firmware_header {
158 	u32 magic;
159 	u32 sequence;
160 	u32 version;
161 	u32 imem_size;
162 	u32 dmem_size;
163 };
164 
165 /* Things we only need during initialization. */
166 struct init_data {
167 	unsigned int dmem_len;
168 	unsigned int imem_len;
169 	unsigned int chksum;
170 	bool is_big_endian;
171 };
172 
173 /* Things we need for as long as we are active. */
174 struct private_data {
175 	void __iomem *regs;
176 	void __iomem *dmem;
177 	void __iomem *imem;
178 	struct device *dev;
179 	struct mutex lock;
180 };
181 
182 static const char *error_text[] = {
183 	"Success", "Header code incorrect", "Unknown command or argument",
184 	"Incorrect checksum", "Malformed command", "Timed out",
185 };
186 
187 /* List of supported firmware commands */
188 static const u32 dpfe_commands[DPFE_CMD_MAX][MSG_FIELD_MAX] = {
189 	[DPFE_CMD_GET_INFO] = {
190 		[MSG_HEADER] = DPFE_MSG_TYPE_COMMAND,
191 		[MSG_COMMAND] = 1,
192 		[MSG_ARG_COUNT] = 1,
193 		[MSG_ARG0] = 1,
194 		[MSG_CHKSUM] = 4,
195 	},
196 	[DPFE_CMD_GET_REFRESH] = {
197 		[MSG_HEADER] = DPFE_MSG_TYPE_COMMAND,
198 		[MSG_COMMAND] = 2,
199 		[MSG_ARG_COUNT] = 1,
200 		[MSG_ARG0] = 1,
201 		[MSG_CHKSUM] = 5,
202 	},
203 	[DPFE_CMD_GET_VENDOR] = {
204 		[MSG_HEADER] = DPFE_MSG_TYPE_COMMAND,
205 		[MSG_COMMAND] = 2,
206 		[MSG_ARG_COUNT] = 1,
207 		[MSG_ARG0] = 2,
208 		[MSG_CHKSUM] = 6,
209 	},
210 };
211 
212 static bool is_dcpu_enabled(void __iomem *regs)
213 {
214 	u32 val;
215 
216 	val = readl_relaxed(regs + REG_DCPU_RESET);
217 
218 	return !(val & DCPU_RESET_MASK);
219 }
220 
221 static void __disable_dcpu(void __iomem *regs)
222 {
223 	u32 val;
224 
225 	if (!is_dcpu_enabled(regs))
226 		return;
227 
228 	/* Put DCPU in reset if it's running. */
229 	val = readl_relaxed(regs + REG_DCPU_RESET);
230 	val |= (1 << DCPU_RESET_SHIFT);
231 	writel_relaxed(val, regs + REG_DCPU_RESET);
232 }
233 
234 static void __enable_dcpu(void __iomem *regs)
235 {
236 	u32 val;
237 
238 	/* Clear mailbox registers. */
239 	writel_relaxed(0, regs + REG_TO_DCPU_MBOX);
240 	writel_relaxed(0, regs + REG_TO_HOST_MBOX);
241 
242 	/* Disable DCPU clock gating */
243 	val = readl_relaxed(regs + REG_DCPU_RESET);
244 	val &= ~(1 << DCPU_CLK_DISABLE_SHIFT);
245 	writel_relaxed(val, regs + REG_DCPU_RESET);
246 
247 	/* Take DCPU out of reset */
248 	val = readl_relaxed(regs + REG_DCPU_RESET);
249 	val &= ~(1 << DCPU_RESET_SHIFT);
250 	writel_relaxed(val, regs + REG_DCPU_RESET);
251 }
252 
253 static unsigned int get_msg_chksum(const u32 msg[])
254 {
255 	unsigned int sum = 0;
256 	unsigned int i;
257 
258 	/* Don't include the last field in the checksum. */
259 	for (i = 0; i < MSG_FIELD_MAX - 1; i++)
260 		sum += msg[i];
261 
262 	return sum;
263 }
264 
265 static void __iomem *get_msg_ptr(struct private_data *priv, u32 response,
266 				 char *buf, ssize_t *size)
267 {
268 	unsigned int msg_type;
269 	unsigned int offset;
270 	void __iomem *ptr = NULL;
271 
272 	msg_type = (response >> DRAM_MSG_TYPE_OFFSET) & DRAM_MSG_TYPE_MASK;
273 	offset = (response >> DRAM_MSG_ADDR_OFFSET) & DRAM_MSG_ADDR_MASK;
274 
275 	/*
276 	 * msg_type == 1: the offset is relative to the message RAM
277 	 * msg_type == 0: the offset is relative to the data RAM (this is the
278 	 *                previous way of passing data)
279 	 * msg_type is anything else: there's critical hardware problem
280 	 */
281 	switch (msg_type) {
282 	case 1:
283 		ptr = priv->regs + DCPU_MSG_RAM_START + offset;
284 		break;
285 	case 0:
286 		ptr = priv->dmem + offset;
287 		break;
288 	default:
289 		dev_emerg(priv->dev, "invalid message reply from DCPU: %#x\n",
290 			response);
291 		if (buf && size)
292 			*size = sprintf(buf,
293 				"FATAL: communication error with DCPU\n");
294 	}
295 
296 	return ptr;
297 }
298 
299 static int __send_command(struct private_data *priv, unsigned int cmd,
300 			  u32 result[])
301 {
302 	const u32 *msg = dpfe_commands[cmd];
303 	void __iomem *regs = priv->regs;
304 	unsigned int i, chksum;
305 	int ret = 0;
306 	u32 resp;
307 
308 	if (cmd >= DPFE_CMD_MAX)
309 		return -1;
310 
311 	mutex_lock(&priv->lock);
312 
313 	/* Write command and arguments to message area */
314 	for (i = 0; i < MSG_FIELD_MAX; i++)
315 		writel_relaxed(msg[i], regs + DCPU_MSG_RAM(i));
316 
317 	/* Tell DCPU there is a command waiting */
318 	writel_relaxed(1, regs + REG_TO_DCPU_MBOX);
319 
320 	/* Wait for DCPU to process the command */
321 	for (i = 0; i < DELAY_LOOP_MAX; i++) {
322 		/* Read response code */
323 		resp = readl_relaxed(regs + REG_TO_HOST_MBOX);
324 		if (resp > 0)
325 			break;
326 		udelay(5);
327 	}
328 
329 	if (i == DELAY_LOOP_MAX) {
330 		resp = (DCPU_RET_ERR_TIMEDOUT & ~DCPU_RET_ERROR_BIT);
331 		ret = -ffs(resp);
332 	} else {
333 		/* Read response data */
334 		for (i = 0; i < MSG_FIELD_MAX; i++)
335 			result[i] = readl_relaxed(regs + DCPU_MSG_RAM(i));
336 	}
337 
338 	/* Tell DCPU we are done */
339 	writel_relaxed(0, regs + REG_TO_HOST_MBOX);
340 
341 	mutex_unlock(&priv->lock);
342 
343 	if (ret)
344 		return ret;
345 
346 	/* Verify response */
347 	chksum = get_msg_chksum(result);
348 	if (chksum != result[MSG_CHKSUM])
349 		resp = DCPU_RET_ERR_CHKSUM;
350 
351 	if (resp != DCPU_RET_SUCCESS) {
352 		resp &= ~DCPU_RET_ERROR_BIT;
353 		ret = -ffs(resp);
354 	}
355 
356 	return ret;
357 }
358 
359 /* Ensure that the firmware file loaded meets all the requirements. */
360 static int __verify_firmware(struct init_data *init,
361 			     const struct firmware *fw)
362 {
363 	const struct dpfe_firmware_header *header = (void *)fw->data;
364 	unsigned int dmem_size, imem_size, total_size;
365 	bool is_big_endian = false;
366 	const u32 *chksum_ptr;
367 
368 	if (header->magic == DPFE_BE_MAGIC)
369 		is_big_endian = true;
370 	else if (header->magic != DPFE_LE_MAGIC)
371 		return ERR_INVALID_MAGIC;
372 
373 	if (is_big_endian) {
374 		dmem_size = be32_to_cpu(header->dmem_size);
375 		imem_size = be32_to_cpu(header->imem_size);
376 	} else {
377 		dmem_size = le32_to_cpu(header->dmem_size);
378 		imem_size = le32_to_cpu(header->imem_size);
379 	}
380 
381 	/* Data and instruction sections are 32 bit words. */
382 	if ((dmem_size % sizeof(u32)) != 0 || (imem_size % sizeof(u32)) != 0)
383 		return ERR_INVALID_SIZE;
384 
385 	/*
386 	 * The header + the data section + the instruction section + the
387 	 * checksum must be equal to the total firmware size.
388 	 */
389 	total_size = dmem_size + imem_size + sizeof(*header) +
390 		sizeof(*chksum_ptr);
391 	if (total_size != fw->size)
392 		return ERR_INVALID_SIZE;
393 
394 	/* The checksum comes at the very end. */
395 	chksum_ptr = (void *)fw->data + sizeof(*header) + dmem_size + imem_size;
396 
397 	init->is_big_endian = is_big_endian;
398 	init->dmem_len = dmem_size;
399 	init->imem_len = imem_size;
400 	init->chksum = (is_big_endian)
401 		? be32_to_cpu(*chksum_ptr) : le32_to_cpu(*chksum_ptr);
402 
403 	return 0;
404 }
405 
406 /* Verify checksum by reading back the firmware from co-processor RAM. */
407 static int __verify_fw_checksum(struct init_data *init,
408 				struct private_data *priv,
409 				const struct dpfe_firmware_header *header,
410 				u32 checksum)
411 {
412 	u32 magic, sequence, version, sum;
413 	u32 __iomem *dmem = priv->dmem;
414 	u32 __iomem *imem = priv->imem;
415 	unsigned int i;
416 
417 	if (init->is_big_endian) {
418 		magic = be32_to_cpu(header->magic);
419 		sequence = be32_to_cpu(header->sequence);
420 		version = be32_to_cpu(header->version);
421 	} else {
422 		magic = le32_to_cpu(header->magic);
423 		sequence = le32_to_cpu(header->sequence);
424 		version = le32_to_cpu(header->version);
425 	}
426 
427 	sum = magic + sequence + version + init->dmem_len + init->imem_len;
428 
429 	for (i = 0; i < init->dmem_len / sizeof(u32); i++)
430 		sum += readl_relaxed(dmem + i);
431 
432 	for (i = 0; i < init->imem_len / sizeof(u32); i++)
433 		sum += readl_relaxed(imem + i);
434 
435 	return (sum == checksum) ? 0 : -1;
436 }
437 
438 static int __write_firmware(u32 __iomem *mem, const u32 *fw,
439 			    unsigned int size, bool is_big_endian)
440 {
441 	unsigned int i;
442 
443 	/* Convert size to 32-bit words. */
444 	size /= sizeof(u32);
445 
446 	/* It is recommended to clear the firmware area first. */
447 	for (i = 0; i < size; i++)
448 		writel_relaxed(0, mem + i);
449 
450 	/* Now copy it. */
451 	if (is_big_endian) {
452 		for (i = 0; i < size; i++)
453 			writel_relaxed(be32_to_cpu(fw[i]), mem + i);
454 	} else {
455 		for (i = 0; i < size; i++)
456 			writel_relaxed(le32_to_cpu(fw[i]), mem + i);
457 	}
458 
459 	return 0;
460 }
461 
462 static int brcmstb_dpfe_download_firmware(struct platform_device *pdev,
463 					  struct init_data *init)
464 {
465 	const struct dpfe_firmware_header *header;
466 	unsigned int dmem_size, imem_size;
467 	struct device *dev = &pdev->dev;
468 	bool is_big_endian = false;
469 	struct private_data *priv;
470 	const struct firmware *fw;
471 	const u32 *dmem, *imem;
472 	const void *fw_blob;
473 	int ret;
474 
475 	priv = platform_get_drvdata(pdev);
476 
477 	/*
478 	 * Skip downloading the firmware if the DCPU is already running and
479 	 * responding to commands.
480 	 */
481 	if (is_dcpu_enabled(priv->regs)) {
482 		u32 response[MSG_FIELD_MAX];
483 
484 		ret = __send_command(priv, DPFE_CMD_GET_INFO, response);
485 		if (!ret)
486 			return 0;
487 	}
488 
489 	ret = request_firmware(&fw, FIRMWARE_NAME, dev);
490 	/* request_firmware() prints its own error messages. */
491 	if (ret)
492 		return ret;
493 
494 	ret = __verify_firmware(init, fw);
495 	if (ret)
496 		return -EFAULT;
497 
498 	__disable_dcpu(priv->regs);
499 
500 	is_big_endian = init->is_big_endian;
501 	dmem_size = init->dmem_len;
502 	imem_size = init->imem_len;
503 
504 	/* At the beginning of the firmware blob is a header. */
505 	header = (struct dpfe_firmware_header *)fw->data;
506 	/* Void pointer to the beginning of the actual firmware. */
507 	fw_blob = fw->data + sizeof(*header);
508 	/* IMEM comes right after the header. */
509 	imem = fw_blob;
510 	/* DMEM follows after IMEM. */
511 	dmem = fw_blob + imem_size;
512 
513 	ret = __write_firmware(priv->dmem, dmem, dmem_size, is_big_endian);
514 	if (ret)
515 		return ret;
516 	ret = __write_firmware(priv->imem, imem, imem_size, is_big_endian);
517 	if (ret)
518 		return ret;
519 
520 	ret = __verify_fw_checksum(init, priv, header, init->chksum);
521 	if (ret)
522 		return ret;
523 
524 	__enable_dcpu(priv->regs);
525 
526 	return 0;
527 }
528 
529 static ssize_t generic_show(unsigned int command, u32 response[],
530 			    struct device *dev, char *buf)
531 {
532 	struct private_data *priv;
533 	int ret;
534 
535 	priv = dev_get_drvdata(dev);
536 	if (!priv)
537 		return sprintf(buf, "ERROR: driver private data not set\n");
538 
539 	ret = __send_command(priv, command, response);
540 	if (ret < 0)
541 		return sprintf(buf, "ERROR: %s\n", error_text[-ret]);
542 
543 	return 0;
544 }
545 
546 static ssize_t show_info(struct device *dev, struct device_attribute *devattr,
547 			 char *buf)
548 {
549 	u32 response[MSG_FIELD_MAX];
550 	unsigned int info;
551 	ssize_t ret;
552 
553 	ret = generic_show(DPFE_CMD_GET_INFO, response, dev, buf);
554 	if (ret)
555 		return ret;
556 
557 	info = response[MSG_ARG0];
558 
559 	return sprintf(buf, "%u.%u.%u.%u\n",
560 		       (info >> 24) & 0xff,
561 		       (info >> 16) & 0xff,
562 		       (info >> 8) & 0xff,
563 		       info & 0xff);
564 }
565 
566 static ssize_t show_refresh(struct device *dev,
567 			    struct device_attribute *devattr, char *buf)
568 {
569 	u32 response[MSG_FIELD_MAX];
570 	void __iomem *info;
571 	struct private_data *priv;
572 	u8 refresh, sr_abort, ppre, thermal_offs, tuf;
573 	u32 mr4;
574 	ssize_t ret;
575 
576 	ret = generic_show(DPFE_CMD_GET_REFRESH, response, dev, buf);
577 	if (ret)
578 		return ret;
579 
580 	priv = dev_get_drvdata(dev);
581 
582 	info = get_msg_ptr(priv, response[MSG_ARG0], buf, &ret);
583 	if (!info)
584 		return ret;
585 
586 	mr4 = readl_relaxed(info + DRAM_INFO_MR4) & DRAM_INFO_MR4_MASK;
587 
588 	refresh = (mr4 >> DRAM_MR4_REFRESH) & DRAM_MR4_REFRESH_MASK;
589 	sr_abort = (mr4 >> DRAM_MR4_SR_ABORT) & DRAM_MR4_SR_ABORT_MASK;
590 	ppre = (mr4 >> DRAM_MR4_PPRE) & DRAM_MR4_PPRE_MASK;
591 	thermal_offs = (mr4 >> DRAM_MR4_TH_OFFS) & DRAM_MR4_TH_OFFS_MASK;
592 	tuf = (mr4 >> DRAM_MR4_TUF) & DRAM_MR4_TUF_MASK;
593 
594 	return sprintf(buf, "%#x %#x %#x %#x %#x %#x %#x\n",
595 		       readl_relaxed(info + DRAM_INFO_INTERVAL),
596 		       refresh, sr_abort, ppre, thermal_offs, tuf,
597 		       readl_relaxed(info + DRAM_INFO_ERROR));
598 }
599 
600 static ssize_t store_refresh(struct device *dev, struct device_attribute *attr,
601 			  const char *buf, size_t count)
602 {
603 	u32 response[MSG_FIELD_MAX];
604 	struct private_data *priv;
605 	void __iomem *info;
606 	unsigned long val;
607 	int ret;
608 
609 	if (kstrtoul(buf, 0, &val) < 0)
610 		return -EINVAL;
611 
612 	priv = dev_get_drvdata(dev);
613 
614 	ret = __send_command(priv, DPFE_CMD_GET_REFRESH, response);
615 	if (ret)
616 		return ret;
617 
618 	info = get_msg_ptr(priv, response[MSG_ARG0], NULL, NULL);
619 	if (!info)
620 		return -EIO;
621 
622 	writel_relaxed(val, info + DRAM_INFO_INTERVAL);
623 
624 	return count;
625 }
626 
627 static ssize_t show_vendor(struct device *dev, struct device_attribute *devattr,
628 			 char *buf)
629 {
630 	u32 response[MSG_FIELD_MAX];
631 	struct private_data *priv;
632 	void __iomem *info;
633 	ssize_t ret;
634 
635 	ret = generic_show(DPFE_CMD_GET_VENDOR, response, dev, buf);
636 	if (ret)
637 		return ret;
638 
639 	priv = dev_get_drvdata(dev);
640 
641 	info = get_msg_ptr(priv, response[MSG_ARG0], buf, &ret);
642 	if (!info)
643 		return ret;
644 
645 	return sprintf(buf, "%#x %#x %#x %#x %#x\n",
646 		       readl_relaxed(info + DRAM_VENDOR_MR5) & DRAM_VENDOR_MASK,
647 		       readl_relaxed(info + DRAM_VENDOR_MR6) & DRAM_VENDOR_MASK,
648 		       readl_relaxed(info + DRAM_VENDOR_MR7) & DRAM_VENDOR_MASK,
649 		       readl_relaxed(info + DRAM_VENDOR_MR8) & DRAM_VENDOR_MASK,
650 		       readl_relaxed(info + DRAM_VENDOR_ERROR) &
651 				     DRAM_VENDOR_MASK);
652 }
653 
654 static int brcmstb_dpfe_resume(struct platform_device *pdev)
655 {
656 	struct init_data init;
657 
658 	return brcmstb_dpfe_download_firmware(pdev, &init);
659 }
660 
661 static DEVICE_ATTR(dpfe_info, 0444, show_info, NULL);
662 static DEVICE_ATTR(dpfe_refresh, 0644, show_refresh, store_refresh);
663 static DEVICE_ATTR(dpfe_vendor, 0444, show_vendor, NULL);
664 static struct attribute *dpfe_attrs[] = {
665 	&dev_attr_dpfe_info.attr,
666 	&dev_attr_dpfe_refresh.attr,
667 	&dev_attr_dpfe_vendor.attr,
668 	NULL
669 };
670 ATTRIBUTE_GROUPS(dpfe);
671 
672 static int brcmstb_dpfe_probe(struct platform_device *pdev)
673 {
674 	struct device *dev = &pdev->dev;
675 	struct private_data *priv;
676 	struct init_data init;
677 	struct resource *res;
678 	int ret;
679 
680 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
681 	if (!priv)
682 		return -ENOMEM;
683 
684 	mutex_init(&priv->lock);
685 	platform_set_drvdata(pdev, priv);
686 
687 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dpfe-cpu");
688 	priv->regs = devm_ioremap_resource(dev, res);
689 	if (IS_ERR(priv->regs)) {
690 		dev_err(dev, "couldn't map DCPU registers\n");
691 		return -ENODEV;
692 	}
693 
694 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dpfe-dmem");
695 	priv->dmem = devm_ioremap_resource(dev, res);
696 	if (IS_ERR(priv->dmem)) {
697 		dev_err(dev, "Couldn't map DCPU data memory\n");
698 		return -ENOENT;
699 	}
700 
701 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dpfe-imem");
702 	priv->imem = devm_ioremap_resource(dev, res);
703 	if (IS_ERR(priv->imem)) {
704 		dev_err(dev, "Couldn't map DCPU instruction memory\n");
705 		return -ENOENT;
706 	}
707 
708 	ret = brcmstb_dpfe_download_firmware(pdev, &init);
709 	if (ret)
710 		return ret;
711 
712 	ret = sysfs_create_groups(&pdev->dev.kobj, dpfe_groups);
713 	if (!ret)
714 		dev_info(dev, "registered.\n");
715 
716 	return ret;
717 }
718 
719 static int brcmstb_dpfe_remove(struct platform_device *pdev)
720 {
721 	sysfs_remove_groups(&pdev->dev.kobj, dpfe_groups);
722 
723 	return 0;
724 }
725 
726 static const struct of_device_id brcmstb_dpfe_of_match[] = {
727 	{ .compatible = "brcm,dpfe-cpu", },
728 	{}
729 };
730 MODULE_DEVICE_TABLE(of, brcmstb_dpfe_of_match);
731 
732 static struct platform_driver brcmstb_dpfe_driver = {
733 	.driver	= {
734 		.name = DRVNAME,
735 		.of_match_table = brcmstb_dpfe_of_match,
736 	},
737 	.probe = brcmstb_dpfe_probe,
738 	.remove	= brcmstb_dpfe_remove,
739 	.resume = brcmstb_dpfe_resume,
740 };
741 
742 module_platform_driver(brcmstb_dpfe_driver);
743 
744 MODULE_AUTHOR("Markus Mayer <mmayer@broadcom.com>");
745 MODULE_DESCRIPTION("BRCMSTB DDR PHY Front End Driver");
746 MODULE_LICENSE("GPL");
747