xref: /openbmc/linux/drivers/memory/brcmstb_dpfe.c (revision 67bf4745)
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/platform_device.h>
37 
38 #define DRVNAME			"brcmstb-dpfe"
39 #define FIRMWARE_NAME		"dpfe.bin"
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 
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 */
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 
84 /* Reset register bits & masks */
85 #define DCPU_RESET_SHIFT	0x0
86 #define DCPU_RESET_MASK		0x1
87 #define DCPU_CLK_DISABLE_SHIFT	0x2
88 
89 /* DCPU return codes */
90 #define DCPU_RET_ERROR_BIT	BIT(31)
91 #define DCPU_RET_SUCCESS	0x1
92 #define DCPU_RET_ERR_HEADER	(DCPU_RET_ERROR_BIT | BIT(0))
93 #define DCPU_RET_ERR_INVAL	(DCPU_RET_ERROR_BIT | BIT(1))
94 #define DCPU_RET_ERR_CHKSUM	(DCPU_RET_ERROR_BIT | BIT(2))
95 #define DCPU_RET_ERR_COMMAND	(DCPU_RET_ERROR_BIT | BIT(3))
96 /* This error code is not firmware defined and only used in the driver. */
97 #define DCPU_RET_ERR_TIMEDOUT	(DCPU_RET_ERROR_BIT | BIT(4))
98 
99 /* Firmware magic */
100 #define DPFE_BE_MAGIC		0xfe1010fe
101 #define DPFE_LE_MAGIC		0xfe0101fe
102 
103 /* Error codes */
104 #define ERR_INVALID_MAGIC	-1
105 #define ERR_INVALID_SIZE	-2
106 #define ERR_INVALID_CHKSUM	-3
107 
108 /* Message types */
109 #define DPFE_MSG_TYPE_COMMAND	1
110 #define DPFE_MSG_TYPE_RESPONSE	2
111 
112 #define DELAY_LOOP_MAX		200000
113 
114 enum dpfe_msg_fields {
115 	MSG_HEADER,
116 	MSG_COMMAND,
117 	MSG_ARG_COUNT,
118 	MSG_ARG0,
119 	MSG_CHKSUM,
120 	MSG_FIELD_MAX /* Last entry */
121 };
122 
123 enum dpfe_commands {
124 	DPFE_CMD_GET_INFO,
125 	DPFE_CMD_GET_REFRESH,
126 	DPFE_CMD_GET_VENDOR,
127 	DPFE_CMD_MAX /* Last entry */
128 };
129 
130 struct dpfe_msg {
131 	u32 header;
132 	u32 command;
133 	u32 arg_count;
134 	u32 arg0;
135 	u32 chksum; /* This is the sum of all other entries. */
136 };
137 
138 /*
139  * Format of the binary firmware file:
140  *
141  *   entry
142  *      0    header
143  *              value:  0xfe0101fe  <== little endian
144  *                      0xfe1010fe  <== big endian
145  *      1    sequence:
146  *              [31:16] total segments on this build
147  *              [15:0]  this segment sequence.
148  *      2    FW version
149  *      3    IMEM byte size
150  *      4    DMEM byte size
151  *           IMEM
152  *           DMEM
153  *      last checksum ==> sum of everything
154  */
155 struct dpfe_firmware_header {
156 	u32 magic;
157 	u32 sequence;
158 	u32 version;
159 	u32 imem_size;
160 	u32 dmem_size;
161 };
162 
163 /* Things we only need during initialization. */
164 struct init_data {
165 	unsigned int dmem_len;
166 	unsigned int imem_len;
167 	unsigned int chksum;
168 	bool is_big_endian;
169 };
170 
171 /* Things we need for as long as we are active. */
172 struct private_data {
173 	void __iomem *regs;
174 	void __iomem *dmem;
175 	void __iomem *imem;
176 	struct device *dev;
177 	struct mutex lock;
178 };
179 
180 static const char *error_text[] = {
181 	"Success", "Header code incorrect", "Unknown command or argument",
182 	"Incorrect checksum", "Malformed command", "Timed out",
183 };
184 
185 /* List of supported firmware commands */
186 static const u32 dpfe_commands[DPFE_CMD_MAX][MSG_FIELD_MAX] = {
187 	[DPFE_CMD_GET_INFO] = {
188 		[MSG_HEADER] = DPFE_MSG_TYPE_COMMAND,
189 		[MSG_COMMAND] = 1,
190 		[MSG_ARG_COUNT] = 1,
191 		[MSG_ARG0] = 1,
192 		[MSG_CHKSUM] = 4,
193 	},
194 	[DPFE_CMD_GET_REFRESH] = {
195 		[MSG_HEADER] = DPFE_MSG_TYPE_COMMAND,
196 		[MSG_COMMAND] = 2,
197 		[MSG_ARG_COUNT] = 1,
198 		[MSG_ARG0] = 1,
199 		[MSG_CHKSUM] = 5,
200 	},
201 	[DPFE_CMD_GET_VENDOR] = {
202 		[MSG_HEADER] = DPFE_MSG_TYPE_COMMAND,
203 		[MSG_COMMAND] = 2,
204 		[MSG_ARG_COUNT] = 1,
205 		[MSG_ARG0] = 2,
206 		[MSG_CHKSUM] = 6,
207 	},
208 };
209 
210 static bool is_dcpu_enabled(void __iomem *regs)
211 {
212 	u32 val;
213 
214 	val = readl_relaxed(regs + REG_DCPU_RESET);
215 
216 	return !(val & DCPU_RESET_MASK);
217 }
218 
219 static void __disable_dcpu(void __iomem *regs)
220 {
221 	u32 val;
222 
223 	if (!is_dcpu_enabled(regs))
224 		return;
225 
226 	/* Put DCPU in reset if it's running. */
227 	val = readl_relaxed(regs + REG_DCPU_RESET);
228 	val |= (1 << DCPU_RESET_SHIFT);
229 	writel_relaxed(val, regs + REG_DCPU_RESET);
230 }
231 
232 static void __enable_dcpu(void __iomem *regs)
233 {
234 	u32 val;
235 
236 	/* Clear mailbox registers. */
237 	writel_relaxed(0, regs + REG_TO_DCPU_MBOX);
238 	writel_relaxed(0, regs + REG_TO_HOST_MBOX);
239 
240 	/* Disable DCPU clock gating */
241 	val = readl_relaxed(regs + REG_DCPU_RESET);
242 	val &= ~(1 << DCPU_CLK_DISABLE_SHIFT);
243 	writel_relaxed(val, regs + REG_DCPU_RESET);
244 
245 	/* Take DCPU out of reset */
246 	val = readl_relaxed(regs + REG_DCPU_RESET);
247 	val &= ~(1 << DCPU_RESET_SHIFT);
248 	writel_relaxed(val, regs + REG_DCPU_RESET);
249 }
250 
251 static unsigned int get_msg_chksum(const u32 msg[])
252 {
253 	unsigned int sum = 0;
254 	unsigned int i;
255 
256 	/* Don't include the last field in the checksum. */
257 	for (i = 0; i < MSG_FIELD_MAX - 1; i++)
258 		sum += msg[i];
259 
260 	return sum;
261 }
262 
263 static void __iomem *get_msg_ptr(struct private_data *priv, u32 response,
264 				 char *buf, ssize_t *size)
265 {
266 	unsigned int msg_type;
267 	unsigned int offset;
268 	void __iomem *ptr = NULL;
269 
270 	msg_type = (response >> DRAM_MSG_TYPE_OFFSET) & DRAM_MSG_TYPE_MASK;
271 	offset = (response >> DRAM_MSG_ADDR_OFFSET) & DRAM_MSG_ADDR_MASK;
272 
273 	/*
274 	 * msg_type == 1: the offset is relative to the message RAM
275 	 * msg_type == 0: the offset is relative to the data RAM (this is the
276 	 *                previous way of passing data)
277 	 * msg_type is anything else: there's critical hardware problem
278 	 */
279 	switch (msg_type) {
280 	case 1:
281 		ptr = priv->regs + DCPU_MSG_RAM_START + offset;
282 		break;
283 	case 0:
284 		ptr = priv->dmem + offset;
285 		break;
286 	default:
287 		dev_emerg(priv->dev, "invalid message reply from DCPU: %#x\n",
288 			response);
289 		if (buf && size)
290 			*size = sprintf(buf,
291 				"FATAL: communication error with DCPU\n");
292 	}
293 
294 	return ptr;
295 }
296 
297 static int __send_command(struct private_data *priv, unsigned int cmd,
298 			  u32 result[])
299 {
300 	const u32 *msg = dpfe_commands[cmd];
301 	void __iomem *regs = priv->regs;
302 	unsigned int i, chksum;
303 	int ret = 0;
304 	u32 resp;
305 
306 	if (cmd >= DPFE_CMD_MAX)
307 		return -1;
308 
309 	mutex_lock(&priv->lock);
310 
311 	/* Write command and arguments to message area */
312 	for (i = 0; i < MSG_FIELD_MAX; i++)
313 		writel_relaxed(msg[i], regs + DCPU_MSG_RAM(i));
314 
315 	/* Tell DCPU there is a command waiting */
316 	writel_relaxed(1, regs + REG_TO_DCPU_MBOX);
317 
318 	/* Wait for DCPU to process the command */
319 	for (i = 0; i < DELAY_LOOP_MAX; i++) {
320 		/* Read response code */
321 		resp = readl_relaxed(regs + REG_TO_HOST_MBOX);
322 		if (resp > 0)
323 			break;
324 		udelay(5);
325 	}
326 
327 	if (i == DELAY_LOOP_MAX) {
328 		resp = (DCPU_RET_ERR_TIMEDOUT & ~DCPU_RET_ERROR_BIT);
329 		ret = -ffs(resp);
330 	} else {
331 		/* Read response data */
332 		for (i = 0; i < MSG_FIELD_MAX; i++)
333 			result[i] = readl_relaxed(regs + DCPU_MSG_RAM(i));
334 	}
335 
336 	/* Tell DCPU we are done */
337 	writel_relaxed(0, regs + REG_TO_HOST_MBOX);
338 
339 	mutex_unlock(&priv->lock);
340 
341 	if (ret)
342 		return ret;
343 
344 	/* Verify response */
345 	chksum = get_msg_chksum(result);
346 	if (chksum != result[MSG_CHKSUM])
347 		resp = DCPU_RET_ERR_CHKSUM;
348 
349 	if (resp != DCPU_RET_SUCCESS) {
350 		resp &= ~DCPU_RET_ERROR_BIT;
351 		ret = -ffs(resp);
352 	}
353 
354 	return ret;
355 }
356 
357 /* Ensure that the firmware file loaded meets all the requirements. */
358 static int __verify_firmware(struct init_data *init,
359 			     const struct firmware *fw)
360 {
361 	const struct dpfe_firmware_header *header = (void *)fw->data;
362 	unsigned int dmem_size, imem_size, total_size;
363 	bool is_big_endian = false;
364 	const u32 *chksum_ptr;
365 
366 	if (header->magic == DPFE_BE_MAGIC)
367 		is_big_endian = true;
368 	else if (header->magic != DPFE_LE_MAGIC)
369 		return ERR_INVALID_MAGIC;
370 
371 	if (is_big_endian) {
372 		dmem_size = be32_to_cpu(header->dmem_size);
373 		imem_size = be32_to_cpu(header->imem_size);
374 	} else {
375 		dmem_size = le32_to_cpu(header->dmem_size);
376 		imem_size = le32_to_cpu(header->imem_size);
377 	}
378 
379 	/* Data and instruction sections are 32 bit words. */
380 	if ((dmem_size % sizeof(u32)) != 0 || (imem_size % sizeof(u32)) != 0)
381 		return ERR_INVALID_SIZE;
382 
383 	/*
384 	 * The header + the data section + the instruction section + the
385 	 * checksum must be equal to the total firmware size.
386 	 */
387 	total_size = dmem_size + imem_size + sizeof(*header) +
388 		sizeof(*chksum_ptr);
389 	if (total_size != fw->size)
390 		return ERR_INVALID_SIZE;
391 
392 	/* The checksum comes at the very end. */
393 	chksum_ptr = (void *)fw->data + sizeof(*header) + dmem_size + imem_size;
394 
395 	init->is_big_endian = is_big_endian;
396 	init->dmem_len = dmem_size;
397 	init->imem_len = imem_size;
398 	init->chksum = (is_big_endian)
399 		? be32_to_cpu(*chksum_ptr) : le32_to_cpu(*chksum_ptr);
400 
401 	return 0;
402 }
403 
404 /* Verify checksum by reading back the firmware from co-processor RAM. */
405 static int __verify_fw_checksum(struct init_data *init,
406 				struct private_data *priv,
407 				const struct dpfe_firmware_header *header,
408 				u32 checksum)
409 {
410 	u32 magic, sequence, version, sum;
411 	u32 __iomem *dmem = priv->dmem;
412 	u32 __iomem *imem = priv->imem;
413 	unsigned int i;
414 
415 	if (init->is_big_endian) {
416 		magic = be32_to_cpu(header->magic);
417 		sequence = be32_to_cpu(header->sequence);
418 		version = be32_to_cpu(header->version);
419 	} else {
420 		magic = le32_to_cpu(header->magic);
421 		sequence = le32_to_cpu(header->sequence);
422 		version = le32_to_cpu(header->version);
423 	}
424 
425 	sum = magic + sequence + version + init->dmem_len + init->imem_len;
426 
427 	for (i = 0; i < init->dmem_len / sizeof(u32); i++)
428 		sum += readl_relaxed(dmem + i);
429 
430 	for (i = 0; i < init->imem_len / sizeof(u32); i++)
431 		sum += readl_relaxed(imem + i);
432 
433 	return (sum == checksum) ? 0 : -1;
434 }
435 
436 static int __write_firmware(u32 __iomem *mem, const u32 *fw,
437 			    unsigned int size, bool is_big_endian)
438 {
439 	unsigned int i;
440 
441 	/* Convert size to 32-bit words. */
442 	size /= sizeof(u32);
443 
444 	/* It is recommended to clear the firmware area first. */
445 	for (i = 0; i < size; i++)
446 		writel_relaxed(0, mem + i);
447 
448 	/* Now copy it. */
449 	if (is_big_endian) {
450 		for (i = 0; i < size; i++)
451 			writel_relaxed(be32_to_cpu(fw[i]), mem + i);
452 	} else {
453 		for (i = 0; i < size; i++)
454 			writel_relaxed(le32_to_cpu(fw[i]), mem + i);
455 	}
456 
457 	return 0;
458 }
459 
460 static int brcmstb_dpfe_download_firmware(struct platform_device *pdev,
461 					  struct init_data *init)
462 {
463 	const struct dpfe_firmware_header *header;
464 	unsigned int dmem_size, imem_size;
465 	struct device *dev = &pdev->dev;
466 	bool is_big_endian = false;
467 	struct private_data *priv;
468 	const struct firmware *fw;
469 	const u32 *dmem, *imem;
470 	const void *fw_blob;
471 	int ret;
472 
473 	priv = platform_get_drvdata(pdev);
474 
475 	/*
476 	 * Skip downloading the firmware if the DCPU is already running and
477 	 * responding to commands.
478 	 */
479 	if (is_dcpu_enabled(priv->regs)) {
480 		u32 response[MSG_FIELD_MAX];
481 
482 		ret = __send_command(priv, DPFE_CMD_GET_INFO, response);
483 		if (!ret)
484 			return 0;
485 	}
486 
487 	ret = request_firmware(&fw, FIRMWARE_NAME, dev);
488 	/* request_firmware() prints its own error messages. */
489 	if (ret)
490 		return ret;
491 
492 	ret = __verify_firmware(init, fw);
493 	if (ret)
494 		return -EFAULT;
495 
496 	__disable_dcpu(priv->regs);
497 
498 	is_big_endian = init->is_big_endian;
499 	dmem_size = init->dmem_len;
500 	imem_size = init->imem_len;
501 
502 	/* At the beginning of the firmware blob is a header. */
503 	header = (struct dpfe_firmware_header *)fw->data;
504 	/* Void pointer to the beginning of the actual firmware. */
505 	fw_blob = fw->data + sizeof(*header);
506 	/* IMEM comes right after the header. */
507 	imem = fw_blob;
508 	/* DMEM follows after IMEM. */
509 	dmem = fw_blob + imem_size;
510 
511 	ret = __write_firmware(priv->dmem, dmem, dmem_size, is_big_endian);
512 	if (ret)
513 		return ret;
514 	ret = __write_firmware(priv->imem, imem, imem_size, is_big_endian);
515 	if (ret)
516 		return ret;
517 
518 	ret = __verify_fw_checksum(init, priv, header, init->chksum);
519 	if (ret)
520 		return ret;
521 
522 	__enable_dcpu(priv->regs);
523 
524 	return 0;
525 }
526 
527 static ssize_t generic_show(unsigned int command, u32 response[],
528 			    struct device *dev, char *buf)
529 {
530 	struct private_data *priv;
531 	int ret;
532 
533 	priv = dev_get_drvdata(dev);
534 	if (!priv)
535 		return sprintf(buf, "ERROR: driver private data not set\n");
536 
537 	ret = __send_command(priv, command, response);
538 	if (ret < 0)
539 		return sprintf(buf, "ERROR: %s\n", error_text[-ret]);
540 
541 	return 0;
542 }
543 
544 static ssize_t show_info(struct device *dev, struct device_attribute *devattr,
545 			 char *buf)
546 {
547 	u32 response[MSG_FIELD_MAX];
548 	unsigned int info;
549 	ssize_t ret;
550 
551 	ret = generic_show(DPFE_CMD_GET_INFO, response, dev, buf);
552 	if (ret)
553 		return ret;
554 
555 	info = response[MSG_ARG0];
556 
557 	return sprintf(buf, "%u.%u.%u.%u\n",
558 		       (info >> 24) & 0xff,
559 		       (info >> 16) & 0xff,
560 		       (info >> 8) & 0xff,
561 		       info & 0xff);
562 }
563 
564 static ssize_t show_refresh(struct device *dev,
565 			    struct device_attribute *devattr, char *buf)
566 {
567 	u32 response[MSG_FIELD_MAX];
568 	void __iomem *info;
569 	struct private_data *priv;
570 	u8 refresh, sr_abort, ppre, thermal_offs, tuf;
571 	u32 mr4;
572 	ssize_t ret;
573 
574 	ret = generic_show(DPFE_CMD_GET_REFRESH, response, dev, buf);
575 	if (ret)
576 		return ret;
577 
578 	priv = dev_get_drvdata(dev);
579 
580 	info = get_msg_ptr(priv, response[MSG_ARG0], buf, &ret);
581 	if (!info)
582 		return ret;
583 
584 	mr4 = readl_relaxed(info + DRAM_INFO_MR4) & DRAM_INFO_MR4_MASK;
585 
586 	refresh = (mr4 >> DRAM_MR4_REFRESH) & DRAM_MR4_REFRESH_MASK;
587 	sr_abort = (mr4 >> DRAM_MR4_SR_ABORT) & DRAM_MR4_SR_ABORT_MASK;
588 	ppre = (mr4 >> DRAM_MR4_PPRE) & DRAM_MR4_PPRE_MASK;
589 	thermal_offs = (mr4 >> DRAM_MR4_TH_OFFS) & DRAM_MR4_TH_OFFS_MASK;
590 	tuf = (mr4 >> DRAM_MR4_TUF) & DRAM_MR4_TUF_MASK;
591 
592 	return sprintf(buf, "%#x %#x %#x %#x %#x %#x %#x\n",
593 		       readl_relaxed(info + DRAM_INFO_INTERVAL),
594 		       refresh, sr_abort, ppre, thermal_offs, tuf,
595 		       readl_relaxed(info + DRAM_INFO_ERROR));
596 }
597 
598 static ssize_t store_refresh(struct device *dev, struct device_attribute *attr,
599 			  const char *buf, size_t count)
600 {
601 	u32 response[MSG_FIELD_MAX];
602 	struct private_data *priv;
603 	void __iomem *info;
604 	unsigned long val;
605 	int ret;
606 
607 	if (kstrtoul(buf, 0, &val) < 0)
608 		return -EINVAL;
609 
610 	priv = dev_get_drvdata(dev);
611 
612 	ret = __send_command(priv, DPFE_CMD_GET_REFRESH, response);
613 	if (ret)
614 		return ret;
615 
616 	info = get_msg_ptr(priv, response[MSG_ARG0], NULL, NULL);
617 	if (!info)
618 		return -EIO;
619 
620 	writel_relaxed(val, info + DRAM_INFO_INTERVAL);
621 
622 	return count;
623 }
624 
625 static ssize_t show_vendor(struct device *dev, struct device_attribute *devattr,
626 			 char *buf)
627 {
628 	u32 response[MSG_FIELD_MAX];
629 	struct private_data *priv;
630 	void __iomem *info;
631 	ssize_t ret;
632 
633 	ret = generic_show(DPFE_CMD_GET_VENDOR, response, dev, buf);
634 	if (ret)
635 		return ret;
636 
637 	priv = dev_get_drvdata(dev);
638 
639 	info = get_msg_ptr(priv, response[MSG_ARG0], buf, &ret);
640 	if (!info)
641 		return ret;
642 
643 	return sprintf(buf, "%#x %#x %#x %#x %#x\n",
644 		       readl_relaxed(info + DRAM_VENDOR_MR5) & DRAM_VENDOR_MASK,
645 		       readl_relaxed(info + DRAM_VENDOR_MR6) & DRAM_VENDOR_MASK,
646 		       readl_relaxed(info + DRAM_VENDOR_MR7) & DRAM_VENDOR_MASK,
647 		       readl_relaxed(info + DRAM_VENDOR_MR8) & DRAM_VENDOR_MASK,
648 		       readl_relaxed(info + DRAM_VENDOR_ERROR) &
649 				     DRAM_VENDOR_MASK);
650 }
651 
652 static int brcmstb_dpfe_resume(struct platform_device *pdev)
653 {
654 	struct init_data init;
655 
656 	return brcmstb_dpfe_download_firmware(pdev, &init);
657 }
658 
659 static DEVICE_ATTR(dpfe_info, 0444, show_info, NULL);
660 static DEVICE_ATTR(dpfe_refresh, 0644, show_refresh, store_refresh);
661 static DEVICE_ATTR(dpfe_vendor, 0444, show_vendor, NULL);
662 static struct attribute *dpfe_attrs[] = {
663 	&dev_attr_dpfe_info.attr,
664 	&dev_attr_dpfe_refresh.attr,
665 	&dev_attr_dpfe_vendor.attr,
666 	NULL
667 };
668 ATTRIBUTE_GROUPS(dpfe);
669 
670 static int brcmstb_dpfe_probe(struct platform_device *pdev)
671 {
672 	struct device *dev = &pdev->dev;
673 	struct private_data *priv;
674 	struct init_data init;
675 	struct resource *res;
676 	int ret;
677 
678 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
679 	if (!priv)
680 		return -ENOMEM;
681 
682 	mutex_init(&priv->lock);
683 	platform_set_drvdata(pdev, priv);
684 
685 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dpfe-cpu");
686 	priv->regs = devm_ioremap_resource(dev, res);
687 	if (IS_ERR(priv->regs)) {
688 		dev_err(dev, "couldn't map DCPU registers\n");
689 		return -ENODEV;
690 	}
691 
692 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dpfe-dmem");
693 	priv->dmem = devm_ioremap_resource(dev, res);
694 	if (IS_ERR(priv->dmem)) {
695 		dev_err(dev, "Couldn't map DCPU data memory\n");
696 		return -ENOENT;
697 	}
698 
699 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dpfe-imem");
700 	priv->imem = devm_ioremap_resource(dev, res);
701 	if (IS_ERR(priv->imem)) {
702 		dev_err(dev, "Couldn't map DCPU instruction memory\n");
703 		return -ENOENT;
704 	}
705 
706 	ret = brcmstb_dpfe_download_firmware(pdev, &init);
707 	if (ret)
708 		return ret;
709 
710 	ret = sysfs_create_groups(&pdev->dev.kobj, dpfe_groups);
711 	if (!ret)
712 		dev_info(dev, "registered.\n");
713 
714 	return ret;
715 }
716 
717 static int brcmstb_dpfe_remove(struct platform_device *pdev)
718 {
719 	sysfs_remove_groups(&pdev->dev.kobj, dpfe_groups);
720 
721 	return 0;
722 }
723 
724 static const struct of_device_id brcmstb_dpfe_of_match[] = {
725 	{ .compatible = "brcm,dpfe-cpu", },
726 	{}
727 };
728 MODULE_DEVICE_TABLE(of, brcmstb_dpfe_of_match);
729 
730 static struct platform_driver brcmstb_dpfe_driver = {
731 	.driver	= {
732 		.name = DRVNAME,
733 		.of_match_table = brcmstb_dpfe_of_match,
734 	},
735 	.probe = brcmstb_dpfe_probe,
736 	.remove	= brcmstb_dpfe_remove,
737 	.resume = brcmstb_dpfe_resume,
738 };
739 
740 module_platform_driver(brcmstb_dpfe_driver);
741 
742 MODULE_AUTHOR("Markus Mayer <mmayer@broadcom.com>");
743 MODULE_DESCRIPTION("BRCMSTB DDR PHY Front End Driver");
744 MODULE_LICENSE("GPL");
745