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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 
125 enum 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 
134 enum 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  */
158 struct 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. */
167 struct 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 */
175 struct 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. */
183 struct 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 
192 static 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  */
201 static ssize_t show_info(struct device *, struct device_attribute *, char *);
202 static ssize_t show_refresh(struct device *, struct device_attribute *, char *);
203 static ssize_t store_refresh(struct device *, struct device_attribute *,
204 			  const char *, size_t);
205 static ssize_t show_vendor(struct device *, struct device_attribute *, char *);
206 static 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  */
213 static DEVICE_ATTR(dpfe_info, 0444, show_info, NULL);
214 static DEVICE_ATTR(dpfe_refresh, 0644, show_refresh, store_refresh);
215 static DEVICE_ATTR(dpfe_vendor, 0444, show_vendor, NULL);
216 static DEVICE_ATTR(dpfe_dram, 0444, show_dram, NULL);
217 
218 /* API v2 sysfs attributes */
219 static 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 };
225 ATTRIBUTE_GROUPS(dpfe_v2);
226 
227 /* API v3 sysfs attributes */
228 static struct attribute *dpfe_v3_attrs[] = {
229 	&dev_attr_dpfe_info.attr,
230 	&dev_attr_dpfe_dram.attr,
231 	NULL
232 };
233 ATTRIBUTE_GROUPS(dpfe_v3);
234 
235 /* API v2 firmware commands */
236 static 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 */
266 static 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 
is_dcpu_enabled(void __iomem * regs)293 static 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 
__disable_dcpu(void __iomem * regs)302 static 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 
__enable_dcpu(void __iomem * regs)315 static 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 
get_msg_chksum(const u32 msg[],unsigned int max)334 static 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 
get_msg_ptr(struct private_data * priv,u32 response,char * buf,ssize_t * size)346 static 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 
__finalize_command(struct private_data * priv)385 static 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 
__send_command(struct private_data * priv,unsigned int cmd,u32 result[])398 static 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. */
__verify_firmware(struct init_data * init,const struct firmware * fw)472 static 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. */
__verify_fw_checksum(struct init_data * init,struct private_data * priv,const struct dpfe_firmware_header * header,u32 checksum)519 static 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 
__write_firmware(u32 __iomem * mem,const u32 * fw,unsigned int size,bool is_big_endian)550 static 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 
brcmstb_dpfe_download_firmware(struct platform_device * pdev,struct init_data * init)574 static 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 
generic_show(unsigned int command,u32 response[],struct private_data * priv,char * buf)649 static 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 
show_info(struct device * dev,struct device_attribute * devattr,char * buf)664 static 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 
show_refresh(struct device * dev,struct device_attribute * devattr,char * buf)686 static 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 
store_refresh(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)720 static 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 
show_vendor(struct device * dev,struct device_attribute * devattr,char * buf)746 static 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 
show_dram(struct device * dev,struct device_attribute * devattr,char * buf)777 static 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 
brcmstb_dpfe_resume(struct platform_device * pdev)801 static 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 
brcmstb_dpfe_probe(struct platform_device * pdev)808 static 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 
brcmstb_dpfe_remove(struct platform_device * pdev)868 static 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 
877 static 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 };
887 MODULE_DEVICE_TABLE(of, brcmstb_dpfe_of_match);
888 
889 static 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 
899 module_platform_driver(brcmstb_dpfe_driver);
900 
901 MODULE_AUTHOR("Markus Mayer <mmayer@broadcom.com>");
902 MODULE_DESCRIPTION("BRCMSTB DDR PHY Front End Driver");
903 MODULE_LICENSE("GPL");
904