1 /*
2  * Copyright © 2014 Intel Corporation
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice (including the next
12  * paragraph) shall be included in all copies or substantial portions of the
13  * Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21  * IN THE SOFTWARE.
22  *
23  */
24 
25 #include <linux/firmware.h>
26 
27 #include "i915_drv.h"
28 #include "i915_reg.h"
29 #include "intel_de.h"
30 #include "intel_dmc.h"
31 
32 /**
33  * DOC: DMC Firmware Support
34  *
35  * From gen9 onwards we have newly added DMC (Display microcontroller) in display
36  * engine to save and restore the state of display engine when it enter into
37  * low-power state and comes back to normal.
38  */
39 
40 #define DMC_PATH(platform, major, minor) \
41 	"i915/"				 \
42 	__stringify(platform) "_dmc_ver" \
43 	__stringify(major) "_"		 \
44 	__stringify(minor) ".bin"
45 
46 #define GEN12_DMC_MAX_FW_SIZE		ICL_DMC_MAX_FW_SIZE
47 
48 #define ADLS_DMC_PATH			DMC_PATH(adls, 2, 01)
49 #define ADLS_DMC_VERSION_REQUIRED	DMC_VERSION(2, 1)
50 MODULE_FIRMWARE(ADLS_DMC_PATH);
51 
52 #define DG1_DMC_PATH			DMC_PATH(dg1, 2, 02)
53 #define DG1_DMC_VERSION_REQUIRED	DMC_VERSION(2, 2)
54 MODULE_FIRMWARE(DG1_DMC_PATH);
55 
56 #define RKL_DMC_PATH			DMC_PATH(rkl, 2, 02)
57 #define RKL_DMC_VERSION_REQUIRED	DMC_VERSION(2, 2)
58 MODULE_FIRMWARE(RKL_DMC_PATH);
59 
60 #define TGL_DMC_PATH			DMC_PATH(tgl, 2, 08)
61 #define TGL_DMC_VERSION_REQUIRED	DMC_VERSION(2, 8)
62 MODULE_FIRMWARE(TGL_DMC_PATH);
63 
64 #define ICL_DMC_PATH			DMC_PATH(icl, 1, 09)
65 #define ICL_DMC_VERSION_REQUIRED	DMC_VERSION(1, 9)
66 #define ICL_DMC_MAX_FW_SIZE		0x6000
67 MODULE_FIRMWARE(ICL_DMC_PATH);
68 
69 #define CNL_DMC_PATH			DMC_PATH(cnl, 1, 07)
70 #define CNL_DMC_VERSION_REQUIRED	DMC_VERSION(1, 7)
71 #define CNL_DMC_MAX_FW_SIZE		GLK_DMC_MAX_FW_SIZE
72 MODULE_FIRMWARE(CNL_DMC_PATH);
73 
74 #define GLK_DMC_PATH			DMC_PATH(glk, 1, 04)
75 #define GLK_DMC_VERSION_REQUIRED	DMC_VERSION(1, 4)
76 #define GLK_DMC_MAX_FW_SIZE		0x4000
77 MODULE_FIRMWARE(GLK_DMC_PATH);
78 
79 #define KBL_DMC_PATH			DMC_PATH(kbl, 1, 04)
80 #define KBL_DMC_VERSION_REQUIRED	DMC_VERSION(1, 4)
81 #define KBL_DMC_MAX_FW_SIZE		BXT_DMC_MAX_FW_SIZE
82 MODULE_FIRMWARE(KBL_DMC_PATH);
83 
84 #define SKL_DMC_PATH			DMC_PATH(skl, 1, 27)
85 #define SKL_DMC_VERSION_REQUIRED	DMC_VERSION(1, 27)
86 #define SKL_DMC_MAX_FW_SIZE		BXT_DMC_MAX_FW_SIZE
87 MODULE_FIRMWARE(SKL_DMC_PATH);
88 
89 #define BXT_DMC_PATH			DMC_PATH(bxt, 1, 07)
90 #define BXT_DMC_VERSION_REQUIRED	DMC_VERSION(1, 7)
91 #define BXT_DMC_MAX_FW_SIZE		0x3000
92 MODULE_FIRMWARE(BXT_DMC_PATH);
93 
94 #define DMC_DEFAULT_FW_OFFSET		0xFFFFFFFF
95 #define PACKAGE_MAX_FW_INFO_ENTRIES	20
96 #define PACKAGE_V2_MAX_FW_INFO_ENTRIES	32
97 #define DMC_V1_MAX_MMIO_COUNT		8
98 #define DMC_V3_MAX_MMIO_COUNT		20
99 
100 struct intel_css_header {
101 	/* 0x09 for DMC */
102 	u32 module_type;
103 
104 	/* Includes the DMC specific header in dwords */
105 	u32 header_len;
106 
107 	/* always value would be 0x10000 */
108 	u32 header_ver;
109 
110 	/* Not used */
111 	u32 module_id;
112 
113 	/* Not used */
114 	u32 module_vendor;
115 
116 	/* in YYYYMMDD format */
117 	u32 date;
118 
119 	/* Size in dwords (CSS_Headerlen + PackageHeaderLen + dmc FWsLen)/4 */
120 	u32 size;
121 
122 	/* Not used */
123 	u32 key_size;
124 
125 	/* Not used */
126 	u32 modulus_size;
127 
128 	/* Not used */
129 	u32 exponent_size;
130 
131 	/* Not used */
132 	u32 reserved1[12];
133 
134 	/* Major Minor */
135 	u32 version;
136 
137 	/* Not used */
138 	u32 reserved2[8];
139 
140 	/* Not used */
141 	u32 kernel_header_info;
142 } __packed;
143 
144 struct intel_fw_info {
145 	u8 reserved1;
146 
147 	/* reserved on package_header version 1, must be 0 on version 2 */
148 	u8 dmc_id;
149 
150 	/* Stepping (A, B, C, ..., *). * is a wildcard */
151 	char stepping;
152 
153 	/* Sub-stepping (0, 1, ..., *). * is a wildcard */
154 	char substepping;
155 
156 	u32 offset;
157 	u32 reserved2;
158 } __packed;
159 
160 struct intel_package_header {
161 	/* DMC container header length in dwords */
162 	u8 header_len;
163 
164 	/* 0x01, 0x02 */
165 	u8 header_ver;
166 
167 	u8 reserved[10];
168 
169 	/* Number of valid entries in the FWInfo array below */
170 	u32 num_entries;
171 } __packed;
172 
173 struct intel_dmc_header_base {
174 	/* always value would be 0x40403E3E */
175 	u32 signature;
176 
177 	/* DMC binary header length */
178 	u8 header_len;
179 
180 	/* 0x01 */
181 	u8 header_ver;
182 
183 	/* Reserved */
184 	u16 dmcc_ver;
185 
186 	/* Major, Minor */
187 	u32 project;
188 
189 	/* Firmware program size (excluding header) in dwords */
190 	u32 fw_size;
191 
192 	/* Major Minor version */
193 	u32 fw_version;
194 } __packed;
195 
196 struct intel_dmc_header_v1 {
197 	struct intel_dmc_header_base base;
198 
199 	/* Number of valid MMIO cycles present. */
200 	u32 mmio_count;
201 
202 	/* MMIO address */
203 	u32 mmioaddr[DMC_V1_MAX_MMIO_COUNT];
204 
205 	/* MMIO data */
206 	u32 mmiodata[DMC_V1_MAX_MMIO_COUNT];
207 
208 	/* FW filename  */
209 	char dfile[32];
210 
211 	u32 reserved1[2];
212 } __packed;
213 
214 struct intel_dmc_header_v3 {
215 	struct intel_dmc_header_base base;
216 
217 	/* DMC RAM start MMIO address */
218 	u32 start_mmioaddr;
219 
220 	u32 reserved[9];
221 
222 	/* FW filename */
223 	char dfile[32];
224 
225 	/* Number of valid MMIO cycles present. */
226 	u32 mmio_count;
227 
228 	/* MMIO address */
229 	u32 mmioaddr[DMC_V3_MAX_MMIO_COUNT];
230 
231 	/* MMIO data */
232 	u32 mmiodata[DMC_V3_MAX_MMIO_COUNT];
233 } __packed;
234 
235 struct stepping_info {
236 	char stepping;
237 	char substepping;
238 };
239 
240 bool intel_dmc_has_payload(struct drm_i915_private *i915)
241 {
242 	return i915->dmc.dmc_payload;
243 }
244 
245 static const struct stepping_info skl_stepping_info[] = {
246 	{'A', '0'}, {'B', '0'}, {'C', '0'},
247 	{'D', '0'}, {'E', '0'}, {'F', '0'},
248 	{'G', '0'}, {'H', '0'}, {'I', '0'},
249 	{'J', '0'}, {'K', '0'}
250 };
251 
252 static const struct stepping_info bxt_stepping_info[] = {
253 	{'A', '0'}, {'A', '1'}, {'A', '2'},
254 	{'B', '0'}, {'B', '1'}, {'B', '2'}
255 };
256 
257 static const struct stepping_info icl_stepping_info[] = {
258 	{'A', '0'}, {'A', '1'}, {'A', '2'},
259 	{'B', '0'}, {'B', '2'},
260 	{'C', '0'}
261 };
262 
263 static const struct stepping_info no_stepping_info = { '*', '*' };
264 
265 static const struct stepping_info *
266 intel_get_stepping_info(struct drm_i915_private *dev_priv)
267 {
268 	const struct stepping_info *si;
269 	unsigned int size;
270 
271 	if (IS_ICELAKE(dev_priv)) {
272 		size = ARRAY_SIZE(icl_stepping_info);
273 		si = icl_stepping_info;
274 	} else if (IS_SKYLAKE(dev_priv)) {
275 		size = ARRAY_SIZE(skl_stepping_info);
276 		si = skl_stepping_info;
277 	} else if (IS_BROXTON(dev_priv)) {
278 		size = ARRAY_SIZE(bxt_stepping_info);
279 		si = bxt_stepping_info;
280 	} else {
281 		size = 0;
282 		si = NULL;
283 	}
284 
285 	if (INTEL_REVID(dev_priv) < size)
286 		return si + INTEL_REVID(dev_priv);
287 
288 	return &no_stepping_info;
289 }
290 
291 static void gen9_set_dc_state_debugmask(struct drm_i915_private *dev_priv)
292 {
293 	u32 val, mask;
294 
295 	mask = DC_STATE_DEBUG_MASK_MEMORY_UP;
296 
297 	if (IS_GEMINILAKE(dev_priv) || IS_BROXTON(dev_priv))
298 		mask |= DC_STATE_DEBUG_MASK_CORES;
299 
300 	/* The below bit doesn't need to be cleared ever afterwards */
301 	val = intel_de_read(dev_priv, DC_STATE_DEBUG);
302 	if ((val & mask) != mask) {
303 		val |= mask;
304 		intel_de_write(dev_priv, DC_STATE_DEBUG, val);
305 		intel_de_posting_read(dev_priv, DC_STATE_DEBUG);
306 	}
307 }
308 
309 /**
310  * intel_dmc_load_program() - write the firmware from memory to register.
311  * @dev_priv: i915 drm device.
312  *
313  * DMC firmware is read from a .bin file and kept in internal memory one time.
314  * Everytime display comes back from low power state this function is called to
315  * copy the firmware from internal memory to registers.
316  */
317 void intel_dmc_load_program(struct drm_i915_private *dev_priv)
318 {
319 	u32 *payload = dev_priv->dmc.dmc_payload;
320 	u32 i, fw_size;
321 
322 	if (!HAS_DMC(dev_priv)) {
323 		drm_err(&dev_priv->drm,
324 			"No DMC support available for this platform\n");
325 		return;
326 	}
327 
328 	if (!intel_dmc_has_payload(dev_priv)) {
329 		drm_err(&dev_priv->drm,
330 			"Tried to program CSR with empty payload\n");
331 		return;
332 	}
333 
334 	fw_size = dev_priv->dmc.dmc_fw_size;
335 	assert_rpm_wakelock_held(&dev_priv->runtime_pm);
336 
337 	preempt_disable();
338 
339 	for (i = 0; i < fw_size; i++)
340 		intel_uncore_write_fw(&dev_priv->uncore, DMC_PROGRAM(i),
341 				      payload[i]);
342 
343 	preempt_enable();
344 
345 	for (i = 0; i < dev_priv->dmc.mmio_count; i++) {
346 		intel_de_write(dev_priv, dev_priv->dmc.mmioaddr[i],
347 			       dev_priv->dmc.mmiodata[i]);
348 	}
349 
350 	dev_priv->dmc.dc_state = 0;
351 
352 	gen9_set_dc_state_debugmask(dev_priv);
353 }
354 
355 /*
356  * Search fw_info table for dmc_offset to find firmware binary: num_entries is
357  * already sanitized.
358  */
359 static u32 find_dmc_fw_offset(const struct intel_fw_info *fw_info,
360 			      unsigned int num_entries,
361 			      const struct stepping_info *si,
362 			      u8 package_ver)
363 {
364 	u32 dmc_offset = DMC_DEFAULT_FW_OFFSET;
365 	unsigned int i;
366 
367 	for (i = 0; i < num_entries; i++) {
368 		if (package_ver > 1 && fw_info[i].dmc_id != 0)
369 			continue;
370 
371 		if (fw_info[i].substepping == '*' &&
372 		    si->stepping == fw_info[i].stepping) {
373 			dmc_offset = fw_info[i].offset;
374 			break;
375 		}
376 
377 		if (si->stepping == fw_info[i].stepping &&
378 		    si->substepping == fw_info[i].substepping) {
379 			dmc_offset = fw_info[i].offset;
380 			break;
381 		}
382 
383 		if (fw_info[i].stepping == '*' &&
384 		    fw_info[i].substepping == '*') {
385 			/*
386 			 * In theory we should stop the search as generic
387 			 * entries should always come after the more specific
388 			 * ones, but let's continue to make sure to work even
389 			 * with "broken" firmwares. If we don't find a more
390 			 * specific one, then we use this entry
391 			 */
392 			dmc_offset = fw_info[i].offset;
393 		}
394 	}
395 
396 	return dmc_offset;
397 }
398 
399 static u32 parse_dmc_fw_header(struct intel_dmc *dmc,
400 			       const struct intel_dmc_header_base *dmc_header,
401 			       size_t rem_size)
402 {
403 	struct drm_i915_private *i915 = container_of(dmc, typeof(*i915), dmc);
404 	unsigned int header_len_bytes, dmc_header_size, payload_size, i;
405 	const u32 *mmioaddr, *mmiodata;
406 	u32 mmio_count, mmio_count_max;
407 	u8 *payload;
408 
409 	BUILD_BUG_ON(ARRAY_SIZE(dmc->mmioaddr) < DMC_V3_MAX_MMIO_COUNT ||
410 		     ARRAY_SIZE(dmc->mmioaddr) < DMC_V1_MAX_MMIO_COUNT);
411 
412 	/*
413 	 * Check if we can access common fields, we will checkc again below
414 	 * after we have read the version
415 	 */
416 	if (rem_size < sizeof(struct intel_dmc_header_base))
417 		goto error_truncated;
418 
419 	/* Cope with small differences between v1 and v3 */
420 	if (dmc_header->header_ver == 3) {
421 		const struct intel_dmc_header_v3 *v3 =
422 			(const struct intel_dmc_header_v3 *)dmc_header;
423 
424 		if (rem_size < sizeof(struct intel_dmc_header_v3))
425 			goto error_truncated;
426 
427 		mmioaddr = v3->mmioaddr;
428 		mmiodata = v3->mmiodata;
429 		mmio_count = v3->mmio_count;
430 		mmio_count_max = DMC_V3_MAX_MMIO_COUNT;
431 		/* header_len is in dwords */
432 		header_len_bytes = dmc_header->header_len * 4;
433 		dmc_header_size = sizeof(*v3);
434 	} else if (dmc_header->header_ver == 1) {
435 		const struct intel_dmc_header_v1 *v1 =
436 			(const struct intel_dmc_header_v1 *)dmc_header;
437 
438 		if (rem_size < sizeof(struct intel_dmc_header_v1))
439 			goto error_truncated;
440 
441 		mmioaddr = v1->mmioaddr;
442 		mmiodata = v1->mmiodata;
443 		mmio_count = v1->mmio_count;
444 		mmio_count_max = DMC_V1_MAX_MMIO_COUNT;
445 		header_len_bytes = dmc_header->header_len;
446 		dmc_header_size = sizeof(*v1);
447 	} else {
448 		drm_err(&i915->drm, "Unknown DMC fw header version: %u\n",
449 			dmc_header->header_ver);
450 		return 0;
451 	}
452 
453 	if (header_len_bytes != dmc_header_size) {
454 		drm_err(&i915->drm, "DMC firmware has wrong dmc header length "
455 			"(%u bytes)\n", header_len_bytes);
456 		return 0;
457 	}
458 
459 	/* Cache the dmc header info. */
460 	if (mmio_count > mmio_count_max) {
461 		drm_err(&i915->drm, "DMC firmware has wrong mmio count %u\n", mmio_count);
462 		return 0;
463 	}
464 
465 	for (i = 0; i < mmio_count; i++) {
466 		if (mmioaddr[i] < DMC_MMIO_START_RANGE ||
467 		    mmioaddr[i] > DMC_MMIO_END_RANGE) {
468 			drm_err(&i915->drm, "DMC firmware has wrong mmio address 0x%x\n",
469 				mmioaddr[i]);
470 			return 0;
471 		}
472 		dmc->mmioaddr[i] = _MMIO(mmioaddr[i]);
473 		dmc->mmiodata[i] = mmiodata[i];
474 	}
475 	dmc->mmio_count = mmio_count;
476 
477 	rem_size -= header_len_bytes;
478 
479 	/* fw_size is in dwords, so multiplied by 4 to convert into bytes. */
480 	payload_size = dmc_header->fw_size * 4;
481 	if (rem_size < payload_size)
482 		goto error_truncated;
483 
484 	if (payload_size > dmc->max_fw_size) {
485 		drm_err(&i915->drm, "DMC FW too big (%u bytes)\n", payload_size);
486 		return 0;
487 	}
488 	dmc->dmc_fw_size = dmc_header->fw_size;
489 
490 	dmc->dmc_payload = kmalloc(payload_size, GFP_KERNEL);
491 	if (!dmc->dmc_payload)
492 		return 0;
493 
494 	payload = (u8 *)(dmc_header) + header_len_bytes;
495 	memcpy(dmc->dmc_payload, payload, payload_size);
496 
497 	return header_len_bytes + payload_size;
498 
499 error_truncated:
500 	drm_err(&i915->drm, "Truncated DMC firmware, refusing.\n");
501 	return 0;
502 }
503 
504 static u32
505 parse_dmc_fw_package(struct intel_dmc *dmc,
506 		     const struct intel_package_header *package_header,
507 		     const struct stepping_info *si,
508 		     size_t rem_size)
509 {
510 	struct drm_i915_private *i915 = container_of(dmc, typeof(*i915), dmc);
511 	u32 package_size = sizeof(struct intel_package_header);
512 	u32 num_entries, max_entries, dmc_offset;
513 	const struct intel_fw_info *fw_info;
514 
515 	if (rem_size < package_size)
516 		goto error_truncated;
517 
518 	if (package_header->header_ver == 1) {
519 		max_entries = PACKAGE_MAX_FW_INFO_ENTRIES;
520 	} else if (package_header->header_ver == 2) {
521 		max_entries = PACKAGE_V2_MAX_FW_INFO_ENTRIES;
522 	} else {
523 		drm_err(&i915->drm, "DMC firmware has unknown header version %u\n",
524 			package_header->header_ver);
525 		return 0;
526 	}
527 
528 	/*
529 	 * We should always have space for max_entries,
530 	 * even if not all are used
531 	 */
532 	package_size += max_entries * sizeof(struct intel_fw_info);
533 	if (rem_size < package_size)
534 		goto error_truncated;
535 
536 	if (package_header->header_len * 4 != package_size) {
537 		drm_err(&i915->drm, "DMC firmware has wrong package header length "
538 			"(%u bytes)\n", package_size);
539 		return 0;
540 	}
541 
542 	num_entries = package_header->num_entries;
543 	if (WARN_ON(package_header->num_entries > max_entries))
544 		num_entries = max_entries;
545 
546 	fw_info = (const struct intel_fw_info *)
547 		((u8 *)package_header + sizeof(*package_header));
548 	dmc_offset = find_dmc_fw_offset(fw_info, num_entries, si,
549 					package_header->header_ver);
550 	if (dmc_offset == DMC_DEFAULT_FW_OFFSET) {
551 		drm_err(&i915->drm, "DMC firmware not supported for %c stepping\n",
552 			si->stepping);
553 		return 0;
554 	}
555 
556 	/* dmc_offset is in dwords */
557 	return package_size + dmc_offset * 4;
558 
559 error_truncated:
560 	drm_err(&i915->drm, "Truncated DMC firmware, refusing.\n");
561 	return 0;
562 }
563 
564 /* Return number of bytes parsed or 0 on error */
565 static u32 parse_dmc_fw_css(struct intel_dmc *dmc,
566 			    struct intel_css_header *css_header,
567 			    size_t rem_size)
568 {
569 	struct drm_i915_private *i915 = container_of(dmc, typeof(*i915), dmc);
570 
571 	if (rem_size < sizeof(struct intel_css_header)) {
572 		drm_err(&i915->drm, "Truncated DMC firmware, refusing.\n");
573 		return 0;
574 	}
575 
576 	if (sizeof(struct intel_css_header) !=
577 	    (css_header->header_len * 4)) {
578 		drm_err(&i915->drm, "DMC firmware has wrong CSS header length "
579 			"(%u bytes)\n",
580 			(css_header->header_len * 4));
581 		return 0;
582 	}
583 
584 	if (dmc->required_version &&
585 	    css_header->version != dmc->required_version) {
586 		drm_info(&i915->drm, "Refusing to load DMC firmware v%u.%u,"
587 			 " please use v%u.%u\n",
588 			 DMC_VERSION_MAJOR(css_header->version),
589 			 DMC_VERSION_MINOR(css_header->version),
590 			 DMC_VERSION_MAJOR(dmc->required_version),
591 			 DMC_VERSION_MINOR(dmc->required_version));
592 		return 0;
593 	}
594 
595 	dmc->version = css_header->version;
596 
597 	return sizeof(struct intel_css_header);
598 }
599 
600 static void parse_dmc_fw(struct drm_i915_private *dev_priv,
601 			 const struct firmware *fw)
602 {
603 	struct intel_css_header *css_header;
604 	struct intel_package_header *package_header;
605 	struct intel_dmc_header_base *dmc_header;
606 	struct intel_dmc *dmc = &dev_priv->dmc;
607 	const struct stepping_info *si = intel_get_stepping_info(dev_priv);
608 	u32 readcount = 0;
609 	u32 r;
610 
611 	if (!fw)
612 		return;
613 
614 	/* Extract CSS Header information */
615 	css_header = (struct intel_css_header *)fw->data;
616 	r = parse_dmc_fw_css(dmc, css_header, fw->size);
617 	if (!r)
618 		return;
619 
620 	readcount += r;
621 
622 	/* Extract Package Header information */
623 	package_header = (struct intel_package_header *)&fw->data[readcount];
624 	r = parse_dmc_fw_package(dmc, package_header, si, fw->size - readcount);
625 	if (!r)
626 		return;
627 
628 	readcount += r;
629 
630 	/* Extract dmc_header information */
631 	dmc_header = (struct intel_dmc_header_base *)&fw->data[readcount];
632 	parse_dmc_fw_header(dmc, dmc_header, fw->size - readcount);
633 }
634 
635 static void intel_dmc_runtime_pm_get(struct drm_i915_private *dev_priv)
636 {
637 	drm_WARN_ON(&dev_priv->drm, dev_priv->dmc.wakeref);
638 	dev_priv->dmc.wakeref =
639 		intel_display_power_get(dev_priv, POWER_DOMAIN_INIT);
640 }
641 
642 static void intel_dmc_runtime_pm_put(struct drm_i915_private *dev_priv)
643 {
644 	intel_wakeref_t wakeref __maybe_unused =
645 		fetch_and_zero(&dev_priv->dmc.wakeref);
646 
647 	intel_display_power_put(dev_priv, POWER_DOMAIN_INIT, wakeref);
648 }
649 
650 static void dmc_load_work_fn(struct work_struct *work)
651 {
652 	struct drm_i915_private *dev_priv;
653 	struct intel_dmc *dmc;
654 	const struct firmware *fw = NULL;
655 
656 	dev_priv = container_of(work, typeof(*dev_priv), dmc.work);
657 	dmc = &dev_priv->dmc;
658 
659 	request_firmware(&fw, dev_priv->dmc.fw_path, dev_priv->drm.dev);
660 	parse_dmc_fw(dev_priv, fw);
661 
662 	if (intel_dmc_has_payload(dev_priv)) {
663 		intel_dmc_load_program(dev_priv);
664 		intel_dmc_runtime_pm_put(dev_priv);
665 
666 		drm_info(&dev_priv->drm,
667 			 "Finished loading DMC firmware %s (v%u.%u)\n",
668 			 dev_priv->dmc.fw_path, DMC_VERSION_MAJOR(dmc->version),
669 			 DMC_VERSION_MINOR(dmc->version));
670 	} else {
671 		drm_notice(&dev_priv->drm,
672 			   "Failed to load DMC firmware %s."
673 			   " Disabling runtime power management.\n",
674 			   dmc->fw_path);
675 		drm_notice(&dev_priv->drm, "DMC firmware homepage: %s",
676 			   INTEL_UC_FIRMWARE_URL);
677 	}
678 
679 	release_firmware(fw);
680 }
681 
682 /**
683  * intel_dmc_ucode_init() - initialize the firmware loading.
684  * @dev_priv: i915 drm device.
685  *
686  * This function is called at the time of loading the display driver to read
687  * firmware from a .bin file and copied into a internal memory.
688  */
689 void intel_dmc_ucode_init(struct drm_i915_private *dev_priv)
690 {
691 	struct intel_dmc *dmc = &dev_priv->dmc;
692 
693 	INIT_WORK(&dev_priv->dmc.work, dmc_load_work_fn);
694 
695 	if (!HAS_DMC(dev_priv))
696 		return;
697 
698 	/*
699 	 * Obtain a runtime pm reference, until DMC is loaded, to avoid entering
700 	 * runtime-suspend.
701 	 *
702 	 * On error, we return with the rpm wakeref held to prevent runtime
703 	 * suspend as runtime suspend *requires* a working DMC for whatever
704 	 * reason.
705 	 */
706 	intel_dmc_runtime_pm_get(dev_priv);
707 
708 	if (IS_ALDERLAKE_S(dev_priv)) {
709 		dmc->fw_path = ADLS_DMC_PATH;
710 		dmc->required_version = ADLS_DMC_VERSION_REQUIRED;
711 		dmc->max_fw_size = GEN12_DMC_MAX_FW_SIZE;
712 	} else if (IS_DG1(dev_priv)) {
713 		dmc->fw_path = DG1_DMC_PATH;
714 		dmc->required_version = DG1_DMC_VERSION_REQUIRED;
715 		dmc->max_fw_size = GEN12_DMC_MAX_FW_SIZE;
716 	} else if (IS_ROCKETLAKE(dev_priv)) {
717 		dmc->fw_path = RKL_DMC_PATH;
718 		dmc->required_version = RKL_DMC_VERSION_REQUIRED;
719 		dmc->max_fw_size = GEN12_DMC_MAX_FW_SIZE;
720 	} else if (DISPLAY_VER(dev_priv) >= 12) {
721 		dmc->fw_path = TGL_DMC_PATH;
722 		dmc->required_version = TGL_DMC_VERSION_REQUIRED;
723 		dmc->max_fw_size = GEN12_DMC_MAX_FW_SIZE;
724 	} else if (DISPLAY_VER(dev_priv) == 11) {
725 		dmc->fw_path = ICL_DMC_PATH;
726 		dmc->required_version = ICL_DMC_VERSION_REQUIRED;
727 		dmc->max_fw_size = ICL_DMC_MAX_FW_SIZE;
728 	} else if (IS_CANNONLAKE(dev_priv)) {
729 		dmc->fw_path = CNL_DMC_PATH;
730 		dmc->required_version = CNL_DMC_VERSION_REQUIRED;
731 		dmc->max_fw_size = CNL_DMC_MAX_FW_SIZE;
732 	} else if (IS_GEMINILAKE(dev_priv)) {
733 		dmc->fw_path = GLK_DMC_PATH;
734 		dmc->required_version = GLK_DMC_VERSION_REQUIRED;
735 		dmc->max_fw_size = GLK_DMC_MAX_FW_SIZE;
736 	} else if (IS_KABYLAKE(dev_priv) ||
737 		   IS_COFFEELAKE(dev_priv) ||
738 		   IS_COMETLAKE(dev_priv)) {
739 		dmc->fw_path = KBL_DMC_PATH;
740 		dmc->required_version = KBL_DMC_VERSION_REQUIRED;
741 		dmc->max_fw_size = KBL_DMC_MAX_FW_SIZE;
742 	} else if (IS_SKYLAKE(dev_priv)) {
743 		dmc->fw_path = SKL_DMC_PATH;
744 		dmc->required_version = SKL_DMC_VERSION_REQUIRED;
745 		dmc->max_fw_size = SKL_DMC_MAX_FW_SIZE;
746 	} else if (IS_BROXTON(dev_priv)) {
747 		dmc->fw_path = BXT_DMC_PATH;
748 		dmc->required_version = BXT_DMC_VERSION_REQUIRED;
749 		dmc->max_fw_size = BXT_DMC_MAX_FW_SIZE;
750 	}
751 
752 	if (dev_priv->params.dmc_firmware_path) {
753 		if (strlen(dev_priv->params.dmc_firmware_path) == 0) {
754 			dmc->fw_path = NULL;
755 			drm_info(&dev_priv->drm,
756 				 "Disabling DMC firmware and runtime PM\n");
757 			return;
758 		}
759 
760 		dmc->fw_path = dev_priv->params.dmc_firmware_path;
761 		/* Bypass version check for firmware override. */
762 		dmc->required_version = 0;
763 	}
764 
765 	if (!dmc->fw_path) {
766 		drm_dbg_kms(&dev_priv->drm,
767 			    "No known DMC firmware for platform, disabling runtime PM\n");
768 		return;
769 	}
770 
771 	drm_dbg_kms(&dev_priv->drm, "Loading %s\n", dmc->fw_path);
772 	schedule_work(&dev_priv->dmc.work);
773 }
774 
775 /**
776  * intel_dmc_ucode_suspend() - prepare DMC firmware before system suspend
777  * @dev_priv: i915 drm device
778  *
779  * Prepare the DMC firmware before entering system suspend. This includes
780  * flushing pending work items and releasing any resources acquired during
781  * init.
782  */
783 void intel_dmc_ucode_suspend(struct drm_i915_private *dev_priv)
784 {
785 	if (!HAS_DMC(dev_priv))
786 		return;
787 
788 	flush_work(&dev_priv->dmc.work);
789 
790 	/* Drop the reference held in case DMC isn't loaded. */
791 	if (!intel_dmc_has_payload(dev_priv))
792 		intel_dmc_runtime_pm_put(dev_priv);
793 }
794 
795 /**
796  * intel_dmc_ucode_resume() - init DMC firmware during system resume
797  * @dev_priv: i915 drm device
798  *
799  * Reinitialize the DMC firmware during system resume, reacquiring any
800  * resources released in intel_dmc_ucode_suspend().
801  */
802 void intel_dmc_ucode_resume(struct drm_i915_private *dev_priv)
803 {
804 	if (!HAS_DMC(dev_priv))
805 		return;
806 
807 	/*
808 	 * Reacquire the reference to keep RPM disabled in case DMC isn't
809 	 * loaded.
810 	 */
811 	if (!intel_dmc_has_payload(dev_priv))
812 		intel_dmc_runtime_pm_get(dev_priv);
813 }
814 
815 /**
816  * intel_dmc_ucode_fini() - unload the DMC firmware.
817  * @dev_priv: i915 drm device.
818  *
819  * Firmmware unloading includes freeing the internal memory and reset the
820  * firmware loading status.
821  */
822 void intel_dmc_ucode_fini(struct drm_i915_private *dev_priv)
823 {
824 	if (!HAS_DMC(dev_priv))
825 		return;
826 
827 	intel_dmc_ucode_suspend(dev_priv);
828 	drm_WARN_ON(&dev_priv->drm, dev_priv->dmc.wakeref);
829 
830 	kfree(dev_priv->dmc.dmc_payload);
831 }
832