xref: /linux/drivers/gpu/drm/i915/display/intel_dmc.c (revision ad36a322619c14ba35872129a401ee214bfad875)
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/debugfs.h>
26 #include <linux/firmware.h>
27 
28 #include "i915_drv.h"
29 #include "i915_reg.h"
30 #include "intel_de.h"
31 #include "intel_dmc.h"
32 #include "intel_dmc_regs.h"
33 #include "intel_step.h"
34 
35 /**
36  * DOC: DMC Firmware Support
37  *
38  * From gen9 onwards we have newly added DMC (Display microcontroller) in display
39  * engine to save and restore the state of display engine when it enter into
40  * low-power state and comes back to normal.
41  */
42 
43 #define INTEL_DMC_FIRMWARE_URL "https://git.kernel.org/pub/scm/linux/kernel/git/firmware/linux-firmware.git"
44 
45 enum intel_dmc_id {
46 	DMC_FW_MAIN = 0,
47 	DMC_FW_PIPEA,
48 	DMC_FW_PIPEB,
49 	DMC_FW_PIPEC,
50 	DMC_FW_PIPED,
51 	DMC_FW_MAX
52 };
53 
54 struct intel_dmc {
55 	struct intel_display *display;
56 	struct work_struct work;
57 	const char *fw_path;
58 	u32 max_fw_size; /* bytes */
59 	u32 version;
60 	struct dmc_fw_info {
61 		u32 mmio_count;
62 		i915_reg_t mmioaddr[20];
63 		u32 mmiodata[20];
64 		u32 dmc_offset;
65 		u32 start_mmioaddr;
66 		u32 dmc_fw_size; /*dwords */
67 		u32 *payload;
68 		bool present;
69 	} dmc_info[DMC_FW_MAX];
70 };
71 
72 /* Note: This may be NULL. */
73 static struct intel_dmc *display_to_dmc(struct intel_display *display)
74 {
75 	return display->dmc.dmc;
76 }
77 
78 static const char *dmc_firmware_param(struct intel_display *display)
79 {
80 	const char *p = display->params.dmc_firmware_path;
81 
82 	return p && *p ? p : NULL;
83 }
84 
85 static bool dmc_firmware_param_disabled(struct intel_display *display)
86 {
87 	const char *p = dmc_firmware_param(display);
88 
89 	/* Magic path to indicate disabled */
90 	return p && !strcmp(p, "/dev/null");
91 }
92 
93 #define DMC_VERSION(major, minor)	((major) << 16 | (minor))
94 #define DMC_VERSION_MAJOR(version)	((version) >> 16)
95 #define DMC_VERSION_MINOR(version)	((version) & 0xffff)
96 
97 #define DMC_PATH(platform) \
98 	"i915/" __stringify(platform) "_dmc.bin"
99 
100 /*
101  * New DMC additions should not use this. This is used solely to remain
102  * compatible with systems that have not yet updated DMC blobs to use
103  * unversioned file names.
104  */
105 #define DMC_LEGACY_PATH(platform, major, minor) \
106 	"i915/"					\
107 	__stringify(platform) "_dmc_ver"	\
108 	__stringify(major) "_"			\
109 	__stringify(minor) ".bin"
110 
111 #define XE2LPD_DMC_MAX_FW_SIZE		0x8000
112 #define XELPDP_DMC_MAX_FW_SIZE		0x7000
113 #define DISPLAY_VER13_DMC_MAX_FW_SIZE	0x20000
114 #define DISPLAY_VER12_DMC_MAX_FW_SIZE	ICL_DMC_MAX_FW_SIZE
115 
116 #define XE2LPD_DMC_PATH			DMC_PATH(xe2lpd)
117 MODULE_FIRMWARE(XE2LPD_DMC_PATH);
118 
119 #define BMG_DMC_PATH			DMC_PATH(bmg)
120 MODULE_FIRMWARE(BMG_DMC_PATH);
121 
122 #define MTL_DMC_PATH			DMC_PATH(mtl)
123 MODULE_FIRMWARE(MTL_DMC_PATH);
124 
125 #define DG2_DMC_PATH			DMC_LEGACY_PATH(dg2, 2, 08)
126 MODULE_FIRMWARE(DG2_DMC_PATH);
127 
128 #define ADLP_DMC_PATH			DMC_PATH(adlp)
129 #define ADLP_DMC_FALLBACK_PATH		DMC_LEGACY_PATH(adlp, 2, 16)
130 MODULE_FIRMWARE(ADLP_DMC_PATH);
131 MODULE_FIRMWARE(ADLP_DMC_FALLBACK_PATH);
132 
133 #define ADLS_DMC_PATH			DMC_LEGACY_PATH(adls, 2, 01)
134 MODULE_FIRMWARE(ADLS_DMC_PATH);
135 
136 #define DG1_DMC_PATH			DMC_LEGACY_PATH(dg1, 2, 02)
137 MODULE_FIRMWARE(DG1_DMC_PATH);
138 
139 #define RKL_DMC_PATH			DMC_LEGACY_PATH(rkl, 2, 03)
140 MODULE_FIRMWARE(RKL_DMC_PATH);
141 
142 #define TGL_DMC_PATH			DMC_LEGACY_PATH(tgl, 2, 12)
143 MODULE_FIRMWARE(TGL_DMC_PATH);
144 
145 #define ICL_DMC_PATH			DMC_LEGACY_PATH(icl, 1, 09)
146 #define ICL_DMC_MAX_FW_SIZE		0x6000
147 MODULE_FIRMWARE(ICL_DMC_PATH);
148 
149 #define GLK_DMC_PATH			DMC_LEGACY_PATH(glk, 1, 04)
150 #define GLK_DMC_MAX_FW_SIZE		0x4000
151 MODULE_FIRMWARE(GLK_DMC_PATH);
152 
153 #define KBL_DMC_PATH			DMC_LEGACY_PATH(kbl, 1, 04)
154 #define KBL_DMC_MAX_FW_SIZE		BXT_DMC_MAX_FW_SIZE
155 MODULE_FIRMWARE(KBL_DMC_PATH);
156 
157 #define SKL_DMC_PATH			DMC_LEGACY_PATH(skl, 1, 27)
158 #define SKL_DMC_MAX_FW_SIZE		BXT_DMC_MAX_FW_SIZE
159 MODULE_FIRMWARE(SKL_DMC_PATH);
160 
161 #define BXT_DMC_PATH			DMC_LEGACY_PATH(bxt, 1, 07)
162 #define BXT_DMC_MAX_FW_SIZE		0x3000
163 MODULE_FIRMWARE(BXT_DMC_PATH);
164 
165 static const char *dmc_firmware_default(struct intel_display *display, u32 *size)
166 {
167 	struct drm_i915_private *i915 = to_i915(display->drm);
168 	const char *fw_path = NULL;
169 	u32 max_fw_size = 0;
170 
171 	if (DISPLAY_VER_FULL(display) == IP_VER(20, 0)) {
172 		fw_path = XE2LPD_DMC_PATH;
173 		max_fw_size = XE2LPD_DMC_MAX_FW_SIZE;
174 	} else if (DISPLAY_VER_FULL(display) == IP_VER(14, 1)) {
175 		fw_path = BMG_DMC_PATH;
176 		max_fw_size = XELPDP_DMC_MAX_FW_SIZE;
177 	} else if (DISPLAY_VER_FULL(display) == IP_VER(14, 0)) {
178 		fw_path = MTL_DMC_PATH;
179 		max_fw_size = XELPDP_DMC_MAX_FW_SIZE;
180 	} else if (IS_DG2(i915)) {
181 		fw_path = DG2_DMC_PATH;
182 		max_fw_size = DISPLAY_VER13_DMC_MAX_FW_SIZE;
183 	} else if (IS_ALDERLAKE_P(i915)) {
184 		fw_path = ADLP_DMC_PATH;
185 		max_fw_size = DISPLAY_VER13_DMC_MAX_FW_SIZE;
186 	} else if (IS_ALDERLAKE_S(i915)) {
187 		fw_path = ADLS_DMC_PATH;
188 		max_fw_size = DISPLAY_VER12_DMC_MAX_FW_SIZE;
189 	} else if (IS_DG1(i915)) {
190 		fw_path = DG1_DMC_PATH;
191 		max_fw_size = DISPLAY_VER12_DMC_MAX_FW_SIZE;
192 	} else if (IS_ROCKETLAKE(i915)) {
193 		fw_path = RKL_DMC_PATH;
194 		max_fw_size = DISPLAY_VER12_DMC_MAX_FW_SIZE;
195 	} else if (IS_TIGERLAKE(i915)) {
196 		fw_path = TGL_DMC_PATH;
197 		max_fw_size = DISPLAY_VER12_DMC_MAX_FW_SIZE;
198 	} else if (DISPLAY_VER(display) == 11) {
199 		fw_path = ICL_DMC_PATH;
200 		max_fw_size = ICL_DMC_MAX_FW_SIZE;
201 	} else if (IS_GEMINILAKE(i915)) {
202 		fw_path = GLK_DMC_PATH;
203 		max_fw_size = GLK_DMC_MAX_FW_SIZE;
204 	} else if (IS_KABYLAKE(i915) ||
205 		   IS_COFFEELAKE(i915) ||
206 		   IS_COMETLAKE(i915)) {
207 		fw_path = KBL_DMC_PATH;
208 		max_fw_size = KBL_DMC_MAX_FW_SIZE;
209 	} else if (IS_SKYLAKE(i915)) {
210 		fw_path = SKL_DMC_PATH;
211 		max_fw_size = SKL_DMC_MAX_FW_SIZE;
212 	} else if (IS_BROXTON(i915)) {
213 		fw_path = BXT_DMC_PATH;
214 		max_fw_size = BXT_DMC_MAX_FW_SIZE;
215 	}
216 
217 	*size = max_fw_size;
218 
219 	return fw_path;
220 }
221 
222 #define DMC_DEFAULT_FW_OFFSET		0xFFFFFFFF
223 #define PACKAGE_MAX_FW_INFO_ENTRIES	20
224 #define PACKAGE_V2_MAX_FW_INFO_ENTRIES	32
225 #define DMC_V1_MAX_MMIO_COUNT		8
226 #define DMC_V3_MAX_MMIO_COUNT		20
227 #define DMC_V1_MMIO_START_RANGE		0x80000
228 
229 #define PIPE_TO_DMC_ID(pipe)		 (DMC_FW_PIPEA + ((pipe) - PIPE_A))
230 
231 struct intel_css_header {
232 	/* 0x09 for DMC */
233 	u32 module_type;
234 
235 	/* Includes the DMC specific header in dwords */
236 	u32 header_len;
237 
238 	/* always value would be 0x10000 */
239 	u32 header_ver;
240 
241 	/* Not used */
242 	u32 module_id;
243 
244 	/* Not used */
245 	u32 module_vendor;
246 
247 	/* in YYYYMMDD format */
248 	u32 date;
249 
250 	/* Size in dwords (CSS_Headerlen + PackageHeaderLen + dmc FWsLen)/4 */
251 	u32 size;
252 
253 	/* Not used */
254 	u32 key_size;
255 
256 	/* Not used */
257 	u32 modulus_size;
258 
259 	/* Not used */
260 	u32 exponent_size;
261 
262 	/* Not used */
263 	u32 reserved1[12];
264 
265 	/* Major Minor */
266 	u32 version;
267 
268 	/* Not used */
269 	u32 reserved2[8];
270 
271 	/* Not used */
272 	u32 kernel_header_info;
273 } __packed;
274 
275 struct intel_fw_info {
276 	u8 reserved1;
277 
278 	/* reserved on package_header version 1, must be 0 on version 2 */
279 	u8 dmc_id;
280 
281 	/* Stepping (A, B, C, ..., *). * is a wildcard */
282 	char stepping;
283 
284 	/* Sub-stepping (0, 1, ..., *). * is a wildcard */
285 	char substepping;
286 
287 	u32 offset;
288 	u32 reserved2;
289 } __packed;
290 
291 struct intel_package_header {
292 	/* DMC container header length in dwords */
293 	u8 header_len;
294 
295 	/* 0x01, 0x02 */
296 	u8 header_ver;
297 
298 	u8 reserved[10];
299 
300 	/* Number of valid entries in the FWInfo array below */
301 	u32 num_entries;
302 } __packed;
303 
304 struct intel_dmc_header_base {
305 	/* always value would be 0x40403E3E */
306 	u32 signature;
307 
308 	/* DMC binary header length */
309 	u8 header_len;
310 
311 	/* 0x01 */
312 	u8 header_ver;
313 
314 	/* Reserved */
315 	u16 dmcc_ver;
316 
317 	/* Major, Minor */
318 	u32 project;
319 
320 	/* Firmware program size (excluding header) in dwords */
321 	u32 fw_size;
322 
323 	/* Major Minor version */
324 	u32 fw_version;
325 } __packed;
326 
327 struct intel_dmc_header_v1 {
328 	struct intel_dmc_header_base base;
329 
330 	/* Number of valid MMIO cycles present. */
331 	u32 mmio_count;
332 
333 	/* MMIO address */
334 	u32 mmioaddr[DMC_V1_MAX_MMIO_COUNT];
335 
336 	/* MMIO data */
337 	u32 mmiodata[DMC_V1_MAX_MMIO_COUNT];
338 
339 	/* FW filename  */
340 	char dfile[32];
341 
342 	u32 reserved1[2];
343 } __packed;
344 
345 struct intel_dmc_header_v3 {
346 	struct intel_dmc_header_base base;
347 
348 	/* DMC RAM start MMIO address */
349 	u32 start_mmioaddr;
350 
351 	u32 reserved[9];
352 
353 	/* FW filename */
354 	char dfile[32];
355 
356 	/* Number of valid MMIO cycles present. */
357 	u32 mmio_count;
358 
359 	/* MMIO address */
360 	u32 mmioaddr[DMC_V3_MAX_MMIO_COUNT];
361 
362 	/* MMIO data */
363 	u32 mmiodata[DMC_V3_MAX_MMIO_COUNT];
364 } __packed;
365 
366 struct stepping_info {
367 	char stepping;
368 	char substepping;
369 };
370 
371 #define for_each_dmc_id(__dmc_id) \
372 	for ((__dmc_id) = DMC_FW_MAIN; (__dmc_id) < DMC_FW_MAX; (__dmc_id)++)
373 
374 static bool is_valid_dmc_id(enum intel_dmc_id dmc_id)
375 {
376 	return dmc_id >= DMC_FW_MAIN && dmc_id < DMC_FW_MAX;
377 }
378 
379 static bool has_dmc_id_fw(struct intel_display *display, enum intel_dmc_id dmc_id)
380 {
381 	struct intel_dmc *dmc = display_to_dmc(display);
382 
383 	return dmc && dmc->dmc_info[dmc_id].payload;
384 }
385 
386 bool intel_dmc_has_payload(struct intel_display *display)
387 {
388 	return has_dmc_id_fw(display, DMC_FW_MAIN);
389 }
390 
391 static const struct stepping_info *
392 intel_get_stepping_info(struct intel_display *display,
393 			struct stepping_info *si)
394 {
395 	const char *step_name = intel_step_name(INTEL_DISPLAY_STEP(display));
396 
397 	si->stepping = step_name[0];
398 	si->substepping = step_name[1];
399 	return si;
400 }
401 
402 static void gen9_set_dc_state_debugmask(struct intel_display *display)
403 {
404 	/* The below bit doesn't need to be cleared ever afterwards */
405 	intel_de_rmw(display, DC_STATE_DEBUG, 0,
406 		     DC_STATE_DEBUG_MASK_CORES | DC_STATE_DEBUG_MASK_MEMORY_UP);
407 	intel_de_posting_read(display, DC_STATE_DEBUG);
408 }
409 
410 static void disable_event_handler(struct intel_display *display,
411 				  i915_reg_t ctl_reg, i915_reg_t htp_reg)
412 {
413 	intel_de_write(display, ctl_reg,
414 		       REG_FIELD_PREP(DMC_EVT_CTL_TYPE_MASK,
415 				      DMC_EVT_CTL_TYPE_EDGE_0_1) |
416 		       REG_FIELD_PREP(DMC_EVT_CTL_EVENT_ID_MASK,
417 				      DMC_EVT_CTL_EVENT_ID_FALSE));
418 	intel_de_write(display, htp_reg, 0);
419 }
420 
421 static void disable_all_event_handlers(struct intel_display *display)
422 {
423 	enum intel_dmc_id dmc_id;
424 
425 	/* TODO: disable the event handlers on pre-GEN12 platforms as well */
426 	if (DISPLAY_VER(display) < 12)
427 		return;
428 
429 	for_each_dmc_id(dmc_id) {
430 		int handler;
431 
432 		if (!has_dmc_id_fw(display, dmc_id))
433 			continue;
434 
435 		for (handler = 0; handler < DMC_EVENT_HANDLER_COUNT_GEN12; handler++)
436 			disable_event_handler(display,
437 					      DMC_EVT_CTL(display, dmc_id, handler),
438 					      DMC_EVT_HTP(display, dmc_id, handler));
439 	}
440 }
441 
442 static void adlp_pipedmc_clock_gating_wa(struct intel_display *display, bool enable)
443 {
444 	enum pipe pipe;
445 
446 	/*
447 	 * Wa_16015201720:adl-p,dg2
448 	 * The WA requires clock gating to be disabled all the time
449 	 * for pipe A and B.
450 	 * For pipe C and D clock gating needs to be disabled only
451 	 * during initializing the firmware.
452 	 */
453 	if (enable)
454 		for (pipe = PIPE_A; pipe <= PIPE_D; pipe++)
455 			intel_de_rmw(display, CLKGATE_DIS_PSL_EXT(pipe),
456 				     0, PIPEDMC_GATING_DIS);
457 	else
458 		for (pipe = PIPE_C; pipe <= PIPE_D; pipe++)
459 			intel_de_rmw(display, CLKGATE_DIS_PSL_EXT(pipe),
460 				     PIPEDMC_GATING_DIS, 0);
461 }
462 
463 static void mtl_pipedmc_clock_gating_wa(struct intel_display *display)
464 {
465 	/*
466 	 * Wa_16015201720
467 	 * The WA requires clock gating to be disabled all the time
468 	 * for pipe A and B.
469 	 */
470 	intel_de_rmw(display, GEN9_CLKGATE_DIS_0, 0,
471 		     MTL_PIPEDMC_GATING_DIS_A | MTL_PIPEDMC_GATING_DIS_B);
472 }
473 
474 static void pipedmc_clock_gating_wa(struct intel_display *display, bool enable)
475 {
476 	if (DISPLAY_VER(display) >= 14 && enable)
477 		mtl_pipedmc_clock_gating_wa(display);
478 	else if (DISPLAY_VER(display) == 13)
479 		adlp_pipedmc_clock_gating_wa(display, enable);
480 }
481 
482 void intel_dmc_enable_pipe(struct intel_display *display, enum pipe pipe)
483 {
484 	enum intel_dmc_id dmc_id = PIPE_TO_DMC_ID(pipe);
485 
486 	if (!is_valid_dmc_id(dmc_id) || !has_dmc_id_fw(display, dmc_id))
487 		return;
488 
489 	if (DISPLAY_VER(display) >= 14)
490 		intel_de_rmw(display, MTL_PIPEDMC_CONTROL, 0, PIPEDMC_ENABLE_MTL(pipe));
491 	else
492 		intel_de_rmw(display, PIPEDMC_CONTROL(pipe), 0, PIPEDMC_ENABLE);
493 }
494 
495 void intel_dmc_disable_pipe(struct intel_display *display, enum pipe pipe)
496 {
497 	enum intel_dmc_id dmc_id = PIPE_TO_DMC_ID(pipe);
498 
499 	if (!is_valid_dmc_id(dmc_id) || !has_dmc_id_fw(display, dmc_id))
500 		return;
501 
502 	if (DISPLAY_VER(display) >= 14)
503 		intel_de_rmw(display, MTL_PIPEDMC_CONTROL, PIPEDMC_ENABLE_MTL(pipe), 0);
504 	else
505 		intel_de_rmw(display, PIPEDMC_CONTROL(pipe), PIPEDMC_ENABLE, 0);
506 }
507 
508 static bool is_dmc_evt_ctl_reg(struct intel_display *display,
509 			       enum intel_dmc_id dmc_id, i915_reg_t reg)
510 {
511 	u32 offset = i915_mmio_reg_offset(reg);
512 	u32 start = i915_mmio_reg_offset(DMC_EVT_CTL(display, dmc_id, 0));
513 	u32 end = i915_mmio_reg_offset(DMC_EVT_CTL(display, dmc_id, DMC_EVENT_HANDLER_COUNT_GEN12));
514 
515 	return offset >= start && offset < end;
516 }
517 
518 static bool is_dmc_evt_htp_reg(struct intel_display *display,
519 			       enum intel_dmc_id dmc_id, i915_reg_t reg)
520 {
521 	u32 offset = i915_mmio_reg_offset(reg);
522 	u32 start = i915_mmio_reg_offset(DMC_EVT_HTP(display, dmc_id, 0));
523 	u32 end = i915_mmio_reg_offset(DMC_EVT_HTP(display, dmc_id, DMC_EVENT_HANDLER_COUNT_GEN12));
524 
525 	return offset >= start && offset < end;
526 }
527 
528 static bool disable_dmc_evt(struct intel_display *display,
529 			    enum intel_dmc_id dmc_id,
530 			    i915_reg_t reg, u32 data)
531 {
532 	struct drm_i915_private *i915 = to_i915(display->drm);
533 
534 	if (!is_dmc_evt_ctl_reg(display, dmc_id, reg))
535 		return false;
536 
537 	/* keep all pipe DMC events disabled by default */
538 	if (dmc_id != DMC_FW_MAIN)
539 		return true;
540 
541 	/* also disable the flip queue event on the main DMC on TGL */
542 	if (IS_TIGERLAKE(i915) &&
543 	    REG_FIELD_GET(DMC_EVT_CTL_EVENT_ID_MASK, data) == DMC_EVT_CTL_EVENT_ID_CLK_MSEC)
544 		return true;
545 
546 	/* also disable the HRR event on the main DMC on TGL/ADLS */
547 	if ((IS_TIGERLAKE(i915) || IS_ALDERLAKE_S(i915)) &&
548 	    REG_FIELD_GET(DMC_EVT_CTL_EVENT_ID_MASK, data) == DMC_EVT_CTL_EVENT_ID_VBLANK_A)
549 		return true;
550 
551 	return false;
552 }
553 
554 static u32 dmc_mmiodata(struct intel_display *display,
555 			struct intel_dmc *dmc,
556 			enum intel_dmc_id dmc_id, int i)
557 {
558 	if (disable_dmc_evt(display, dmc_id,
559 			    dmc->dmc_info[dmc_id].mmioaddr[i],
560 			    dmc->dmc_info[dmc_id].mmiodata[i]))
561 		return REG_FIELD_PREP(DMC_EVT_CTL_TYPE_MASK,
562 				      DMC_EVT_CTL_TYPE_EDGE_0_1) |
563 			REG_FIELD_PREP(DMC_EVT_CTL_EVENT_ID_MASK,
564 				       DMC_EVT_CTL_EVENT_ID_FALSE);
565 	else
566 		return dmc->dmc_info[dmc_id].mmiodata[i];
567 }
568 
569 /**
570  * intel_dmc_load_program() - write the firmware from memory to register.
571  * @display: display instance
572  *
573  * DMC firmware is read from a .bin file and kept in internal memory one time.
574  * Everytime display comes back from low power state this function is called to
575  * copy the firmware from internal memory to registers.
576  */
577 void intel_dmc_load_program(struct intel_display *display)
578 {
579 	struct drm_i915_private *i915 __maybe_unused = to_i915(display->drm);
580 	struct i915_power_domains *power_domains = &display->power.domains;
581 	struct intel_dmc *dmc = display_to_dmc(display);
582 	enum intel_dmc_id dmc_id;
583 	u32 i;
584 
585 	if (!intel_dmc_has_payload(display))
586 		return;
587 
588 	pipedmc_clock_gating_wa(display, true);
589 
590 	disable_all_event_handlers(display);
591 
592 	assert_rpm_wakelock_held(&i915->runtime_pm);
593 
594 	preempt_disable();
595 
596 	for_each_dmc_id(dmc_id) {
597 		for (i = 0; i < dmc->dmc_info[dmc_id].dmc_fw_size; i++) {
598 			intel_de_write_fw(display,
599 					  DMC_PROGRAM(dmc->dmc_info[dmc_id].start_mmioaddr, i),
600 					  dmc->dmc_info[dmc_id].payload[i]);
601 		}
602 	}
603 
604 	preempt_enable();
605 
606 	for_each_dmc_id(dmc_id) {
607 		for (i = 0; i < dmc->dmc_info[dmc_id].mmio_count; i++) {
608 			intel_de_write(display, dmc->dmc_info[dmc_id].mmioaddr[i],
609 				       dmc_mmiodata(display, dmc, dmc_id, i));
610 		}
611 	}
612 
613 	power_domains->dc_state = 0;
614 
615 	gen9_set_dc_state_debugmask(display);
616 
617 	pipedmc_clock_gating_wa(display, false);
618 }
619 
620 /**
621  * intel_dmc_disable_program() - disable the firmware
622  * @display: display instance
623  *
624  * Disable all event handlers in the firmware, making sure the firmware is
625  * inactive after the display is uninitialized.
626  */
627 void intel_dmc_disable_program(struct intel_display *display)
628 {
629 	if (!intel_dmc_has_payload(display))
630 		return;
631 
632 	pipedmc_clock_gating_wa(display, true);
633 	disable_all_event_handlers(display);
634 	pipedmc_clock_gating_wa(display, false);
635 
636 	intel_dmc_wl_disable(display);
637 }
638 
639 void assert_dmc_loaded(struct intel_display *display)
640 {
641 	struct intel_dmc *dmc = display_to_dmc(display);
642 
643 	drm_WARN_ONCE(display->drm, !dmc, "DMC not initialized\n");
644 	drm_WARN_ONCE(display->drm, dmc &&
645 		      !intel_de_read(display, DMC_PROGRAM(dmc->dmc_info[DMC_FW_MAIN].start_mmioaddr, 0)),
646 		      "DMC program storage start is NULL\n");
647 	drm_WARN_ONCE(display->drm, !intel_de_read(display, DMC_SSP_BASE),
648 		      "DMC SSP Base Not fine\n");
649 	drm_WARN_ONCE(display->drm, !intel_de_read(display, DMC_HTP_SKL),
650 		      "DMC HTP Not fine\n");
651 }
652 
653 static bool fw_info_matches_stepping(const struct intel_fw_info *fw_info,
654 				     const struct stepping_info *si)
655 {
656 	if ((fw_info->substepping == '*' && si->stepping == fw_info->stepping) ||
657 	    (si->stepping == fw_info->stepping && si->substepping == fw_info->substepping) ||
658 	    /*
659 	     * If we don't find a more specific one from above two checks, we
660 	     * then check for the generic one to be sure to work even with
661 	     * "broken firmware"
662 	     */
663 	    (si->stepping == '*' && si->substepping == fw_info->substepping) ||
664 	    (fw_info->stepping == '*' && fw_info->substepping == '*'))
665 		return true;
666 
667 	return false;
668 }
669 
670 /*
671  * Search fw_info table for dmc_offset to find firmware binary: num_entries is
672  * already sanitized.
673  */
674 static void dmc_set_fw_offset(struct intel_dmc *dmc,
675 			      const struct intel_fw_info *fw_info,
676 			      unsigned int num_entries,
677 			      const struct stepping_info *si,
678 			      u8 package_ver)
679 {
680 	struct intel_display *display = dmc->display;
681 	enum intel_dmc_id dmc_id;
682 	unsigned int i;
683 
684 	for (i = 0; i < num_entries; i++) {
685 		dmc_id = package_ver <= 1 ? DMC_FW_MAIN : fw_info[i].dmc_id;
686 
687 		if (!is_valid_dmc_id(dmc_id)) {
688 			drm_dbg(display->drm, "Unsupported firmware id: %u\n", dmc_id);
689 			continue;
690 		}
691 
692 		/* More specific versions come first, so we don't even have to
693 		 * check for the stepping since we already found a previous FW
694 		 * for this id.
695 		 */
696 		if (dmc->dmc_info[dmc_id].present)
697 			continue;
698 
699 		if (fw_info_matches_stepping(&fw_info[i], si)) {
700 			dmc->dmc_info[dmc_id].present = true;
701 			dmc->dmc_info[dmc_id].dmc_offset = fw_info[i].offset;
702 		}
703 	}
704 }
705 
706 static bool dmc_mmio_addr_sanity_check(struct intel_dmc *dmc,
707 				       const u32 *mmioaddr, u32 mmio_count,
708 				       int header_ver, enum intel_dmc_id dmc_id)
709 {
710 	struct intel_display *display = dmc->display;
711 	u32 start_range, end_range;
712 	int i;
713 
714 	if (header_ver == 1) {
715 		start_range = DMC_MMIO_START_RANGE;
716 		end_range = DMC_MMIO_END_RANGE;
717 	} else if (dmc_id == DMC_FW_MAIN) {
718 		start_range = TGL_MAIN_MMIO_START;
719 		end_range = TGL_MAIN_MMIO_END;
720 	} else if (DISPLAY_VER(display) >= 13) {
721 		start_range = ADLP_PIPE_MMIO_START;
722 		end_range = ADLP_PIPE_MMIO_END;
723 	} else if (DISPLAY_VER(display) >= 12) {
724 		start_range = TGL_PIPE_MMIO_START(dmc_id);
725 		end_range = TGL_PIPE_MMIO_END(dmc_id);
726 	} else {
727 		drm_warn(display->drm, "Unknown mmio range for sanity check");
728 		return false;
729 	}
730 
731 	for (i = 0; i < mmio_count; i++) {
732 		if (mmioaddr[i] < start_range || mmioaddr[i] > end_range)
733 			return false;
734 	}
735 
736 	return true;
737 }
738 
739 static u32 parse_dmc_fw_header(struct intel_dmc *dmc,
740 			       const struct intel_dmc_header_base *dmc_header,
741 			       size_t rem_size, enum intel_dmc_id dmc_id)
742 {
743 	struct intel_display *display = dmc->display;
744 	struct dmc_fw_info *dmc_info = &dmc->dmc_info[dmc_id];
745 	unsigned int header_len_bytes, dmc_header_size, payload_size, i;
746 	const u32 *mmioaddr, *mmiodata;
747 	u32 mmio_count, mmio_count_max, start_mmioaddr;
748 	u8 *payload;
749 
750 	BUILD_BUG_ON(ARRAY_SIZE(dmc_info->mmioaddr) < DMC_V3_MAX_MMIO_COUNT ||
751 		     ARRAY_SIZE(dmc_info->mmioaddr) < DMC_V1_MAX_MMIO_COUNT);
752 
753 	/*
754 	 * Check if we can access common fields, we will checkc again below
755 	 * after we have read the version
756 	 */
757 	if (rem_size < sizeof(struct intel_dmc_header_base))
758 		goto error_truncated;
759 
760 	/* Cope with small differences between v1 and v3 */
761 	if (dmc_header->header_ver == 3) {
762 		const struct intel_dmc_header_v3 *v3 =
763 			(const struct intel_dmc_header_v3 *)dmc_header;
764 
765 		if (rem_size < sizeof(struct intel_dmc_header_v3))
766 			goto error_truncated;
767 
768 		mmioaddr = v3->mmioaddr;
769 		mmiodata = v3->mmiodata;
770 		mmio_count = v3->mmio_count;
771 		mmio_count_max = DMC_V3_MAX_MMIO_COUNT;
772 		/* header_len is in dwords */
773 		header_len_bytes = dmc_header->header_len * 4;
774 		start_mmioaddr = v3->start_mmioaddr;
775 		dmc_header_size = sizeof(*v3);
776 	} else if (dmc_header->header_ver == 1) {
777 		const struct intel_dmc_header_v1 *v1 =
778 			(const struct intel_dmc_header_v1 *)dmc_header;
779 
780 		if (rem_size < sizeof(struct intel_dmc_header_v1))
781 			goto error_truncated;
782 
783 		mmioaddr = v1->mmioaddr;
784 		mmiodata = v1->mmiodata;
785 		mmio_count = v1->mmio_count;
786 		mmio_count_max = DMC_V1_MAX_MMIO_COUNT;
787 		header_len_bytes = dmc_header->header_len;
788 		start_mmioaddr = DMC_V1_MMIO_START_RANGE;
789 		dmc_header_size = sizeof(*v1);
790 	} else {
791 		drm_err(display->drm, "Unknown DMC fw header version: %u\n",
792 			dmc_header->header_ver);
793 		return 0;
794 	}
795 
796 	if (header_len_bytes != dmc_header_size) {
797 		drm_err(display->drm, "DMC firmware has wrong dmc header length "
798 			"(%u bytes)\n", header_len_bytes);
799 		return 0;
800 	}
801 
802 	/* Cache the dmc header info. */
803 	if (mmio_count > mmio_count_max) {
804 		drm_err(display->drm, "DMC firmware has wrong mmio count %u\n", mmio_count);
805 		return 0;
806 	}
807 
808 	if (!dmc_mmio_addr_sanity_check(dmc, mmioaddr, mmio_count,
809 					dmc_header->header_ver, dmc_id)) {
810 		drm_err(display->drm, "DMC firmware has Wrong MMIO Addresses\n");
811 		return 0;
812 	}
813 
814 	drm_dbg_kms(display->drm, "DMC %d:\n", dmc_id);
815 	for (i = 0; i < mmio_count; i++) {
816 		dmc_info->mmioaddr[i] = _MMIO(mmioaddr[i]);
817 		dmc_info->mmiodata[i] = mmiodata[i];
818 
819 		drm_dbg_kms(display->drm, " mmio[%d]: 0x%x = 0x%x%s%s\n",
820 			    i, mmioaddr[i], mmiodata[i],
821 			    is_dmc_evt_ctl_reg(display, dmc_id, dmc_info->mmioaddr[i]) ? " (EVT_CTL)" :
822 			    is_dmc_evt_htp_reg(display, dmc_id, dmc_info->mmioaddr[i]) ? " (EVT_HTP)" : "",
823 			    disable_dmc_evt(display, dmc_id, dmc_info->mmioaddr[i],
824 					    dmc_info->mmiodata[i]) ? " (disabling)" : "");
825 	}
826 	dmc_info->mmio_count = mmio_count;
827 	dmc_info->start_mmioaddr = start_mmioaddr;
828 
829 	rem_size -= header_len_bytes;
830 
831 	/* fw_size is in dwords, so multiplied by 4 to convert into bytes. */
832 	payload_size = dmc_header->fw_size * 4;
833 	if (rem_size < payload_size)
834 		goto error_truncated;
835 
836 	if (payload_size > dmc->max_fw_size) {
837 		drm_err(display->drm, "DMC FW too big (%u bytes)\n", payload_size);
838 		return 0;
839 	}
840 	dmc_info->dmc_fw_size = dmc_header->fw_size;
841 
842 	dmc_info->payload = kmalloc(payload_size, GFP_KERNEL);
843 	if (!dmc_info->payload)
844 		return 0;
845 
846 	payload = (u8 *)(dmc_header) + header_len_bytes;
847 	memcpy(dmc_info->payload, payload, payload_size);
848 
849 	return header_len_bytes + payload_size;
850 
851 error_truncated:
852 	drm_err(display->drm, "Truncated DMC firmware, refusing.\n");
853 	return 0;
854 }
855 
856 static u32
857 parse_dmc_fw_package(struct intel_dmc *dmc,
858 		     const struct intel_package_header *package_header,
859 		     const struct stepping_info *si,
860 		     size_t rem_size)
861 {
862 	struct intel_display *display = dmc->display;
863 	u32 package_size = sizeof(struct intel_package_header);
864 	u32 num_entries, max_entries;
865 	const struct intel_fw_info *fw_info;
866 
867 	if (rem_size < package_size)
868 		goto error_truncated;
869 
870 	if (package_header->header_ver == 1) {
871 		max_entries = PACKAGE_MAX_FW_INFO_ENTRIES;
872 	} else if (package_header->header_ver == 2) {
873 		max_entries = PACKAGE_V2_MAX_FW_INFO_ENTRIES;
874 	} else {
875 		drm_err(display->drm, "DMC firmware has unknown header version %u\n",
876 			package_header->header_ver);
877 		return 0;
878 	}
879 
880 	/*
881 	 * We should always have space for max_entries,
882 	 * even if not all are used
883 	 */
884 	package_size += max_entries * sizeof(struct intel_fw_info);
885 	if (rem_size < package_size)
886 		goto error_truncated;
887 
888 	if (package_header->header_len * 4 != package_size) {
889 		drm_err(display->drm, "DMC firmware has wrong package header length "
890 			"(%u bytes)\n", package_size);
891 		return 0;
892 	}
893 
894 	num_entries = package_header->num_entries;
895 	if (WARN_ON(package_header->num_entries > max_entries))
896 		num_entries = max_entries;
897 
898 	fw_info = (const struct intel_fw_info *)
899 		((u8 *)package_header + sizeof(*package_header));
900 	dmc_set_fw_offset(dmc, fw_info, num_entries, si,
901 			  package_header->header_ver);
902 
903 	/* dmc_offset is in dwords */
904 	return package_size;
905 
906 error_truncated:
907 	drm_err(display->drm, "Truncated DMC firmware, refusing.\n");
908 	return 0;
909 }
910 
911 /* Return number of bytes parsed or 0 on error */
912 static u32 parse_dmc_fw_css(struct intel_dmc *dmc,
913 			    struct intel_css_header *css_header,
914 			    size_t rem_size)
915 {
916 	struct intel_display *display = dmc->display;
917 
918 	if (rem_size < sizeof(struct intel_css_header)) {
919 		drm_err(display->drm, "Truncated DMC firmware, refusing.\n");
920 		return 0;
921 	}
922 
923 	if (sizeof(struct intel_css_header) !=
924 	    (css_header->header_len * 4)) {
925 		drm_err(display->drm, "DMC firmware has wrong CSS header length "
926 			"(%u bytes)\n",
927 			(css_header->header_len * 4));
928 		return 0;
929 	}
930 
931 	dmc->version = css_header->version;
932 
933 	return sizeof(struct intel_css_header);
934 }
935 
936 static int parse_dmc_fw(struct intel_dmc *dmc, const struct firmware *fw)
937 {
938 	struct intel_display *display = dmc->display;
939 	struct intel_css_header *css_header;
940 	struct intel_package_header *package_header;
941 	struct intel_dmc_header_base *dmc_header;
942 	struct stepping_info display_info = { '*', '*'};
943 	const struct stepping_info *si = intel_get_stepping_info(display, &display_info);
944 	enum intel_dmc_id dmc_id;
945 	u32 readcount = 0;
946 	u32 r, offset;
947 
948 	if (!fw)
949 		return -EINVAL;
950 
951 	/* Extract CSS Header information */
952 	css_header = (struct intel_css_header *)fw->data;
953 	r = parse_dmc_fw_css(dmc, css_header, fw->size);
954 	if (!r)
955 		return -EINVAL;
956 
957 	readcount += r;
958 
959 	/* Extract Package Header information */
960 	package_header = (struct intel_package_header *)&fw->data[readcount];
961 	r = parse_dmc_fw_package(dmc, package_header, si, fw->size - readcount);
962 	if (!r)
963 		return -EINVAL;
964 
965 	readcount += r;
966 
967 	for_each_dmc_id(dmc_id) {
968 		if (!dmc->dmc_info[dmc_id].present)
969 			continue;
970 
971 		offset = readcount + dmc->dmc_info[dmc_id].dmc_offset * 4;
972 		if (offset > fw->size) {
973 			drm_err(display->drm, "Reading beyond the fw_size\n");
974 			continue;
975 		}
976 
977 		dmc_header = (struct intel_dmc_header_base *)&fw->data[offset];
978 		parse_dmc_fw_header(dmc, dmc_header, fw->size - offset, dmc_id);
979 	}
980 
981 	if (!intel_dmc_has_payload(display)) {
982 		drm_err(display->drm, "DMC firmware main program not found\n");
983 		return -ENOENT;
984 	}
985 
986 	return 0;
987 }
988 
989 static void intel_dmc_runtime_pm_get(struct intel_display *display)
990 {
991 	struct drm_i915_private *i915 = to_i915(display->drm);
992 
993 	drm_WARN_ON(display->drm, display->dmc.wakeref);
994 	display->dmc.wakeref = intel_display_power_get(i915, POWER_DOMAIN_INIT);
995 }
996 
997 static void intel_dmc_runtime_pm_put(struct intel_display *display)
998 {
999 	struct drm_i915_private *i915 = to_i915(display->drm);
1000 	intel_wakeref_t wakeref __maybe_unused =
1001 		fetch_and_zero(&display->dmc.wakeref);
1002 
1003 	intel_display_power_put(i915, POWER_DOMAIN_INIT, wakeref);
1004 }
1005 
1006 static const char *dmc_fallback_path(struct intel_display *display)
1007 {
1008 	struct drm_i915_private *i915 = to_i915(display->drm);
1009 
1010 	if (IS_ALDERLAKE_P(i915))
1011 		return ADLP_DMC_FALLBACK_PATH;
1012 
1013 	return NULL;
1014 }
1015 
1016 static void dmc_load_work_fn(struct work_struct *work)
1017 {
1018 	struct intel_dmc *dmc = container_of(work, typeof(*dmc), work);
1019 	struct intel_display *display = dmc->display;
1020 	const struct firmware *fw = NULL;
1021 	const char *fallback_path;
1022 	int err;
1023 
1024 	err = request_firmware(&fw, dmc->fw_path, display->drm->dev);
1025 
1026 	if (err == -ENOENT && !dmc_firmware_param(display)) {
1027 		fallback_path = dmc_fallback_path(display);
1028 		if (fallback_path) {
1029 			drm_dbg_kms(display->drm, "%s not found, falling back to %s\n",
1030 				    dmc->fw_path, fallback_path);
1031 			err = request_firmware(&fw, fallback_path, display->drm->dev);
1032 			if (err == 0)
1033 				dmc->fw_path = fallback_path;
1034 		}
1035 	}
1036 
1037 	if (err) {
1038 		drm_notice(display->drm,
1039 			   "Failed to load DMC firmware %s (%pe). Disabling runtime power management.\n",
1040 			   dmc->fw_path, ERR_PTR(err));
1041 		drm_notice(display->drm, "DMC firmware homepage: %s",
1042 			   INTEL_DMC_FIRMWARE_URL);
1043 		return;
1044 	}
1045 
1046 	err = parse_dmc_fw(dmc, fw);
1047 	if (err) {
1048 		drm_notice(display->drm,
1049 			   "Failed to parse DMC firmware %s (%pe). Disabling runtime power management.\n",
1050 			   dmc->fw_path, ERR_PTR(err));
1051 		goto out;
1052 	}
1053 
1054 	intel_dmc_load_program(display);
1055 	intel_dmc_runtime_pm_put(display);
1056 
1057 	drm_info(display->drm, "Finished loading DMC firmware %s (v%u.%u)\n",
1058 		 dmc->fw_path, DMC_VERSION_MAJOR(dmc->version),
1059 		 DMC_VERSION_MINOR(dmc->version));
1060 
1061 out:
1062 	release_firmware(fw);
1063 }
1064 
1065 /**
1066  * intel_dmc_init() - initialize the firmware loading.
1067  * @display: display instance
1068  *
1069  * This function is called at the time of loading the display driver to read
1070  * firmware from a .bin file and copied into a internal memory.
1071  */
1072 void intel_dmc_init(struct intel_display *display)
1073 {
1074 	struct drm_i915_private *i915 = to_i915(display->drm);
1075 	struct intel_dmc *dmc;
1076 
1077 	if (!HAS_DMC(display))
1078 		return;
1079 
1080 	/*
1081 	 * Obtain a runtime pm reference, until DMC is loaded, to avoid entering
1082 	 * runtime-suspend.
1083 	 *
1084 	 * On error, we return with the rpm wakeref held to prevent runtime
1085 	 * suspend as runtime suspend *requires* a working DMC for whatever
1086 	 * reason.
1087 	 */
1088 	intel_dmc_runtime_pm_get(display);
1089 
1090 	dmc = kzalloc(sizeof(*dmc), GFP_KERNEL);
1091 	if (!dmc)
1092 		return;
1093 
1094 	dmc->display = display;
1095 
1096 	INIT_WORK(&dmc->work, dmc_load_work_fn);
1097 
1098 	dmc->fw_path = dmc_firmware_default(display, &dmc->max_fw_size);
1099 
1100 	if (dmc_firmware_param_disabled(display)) {
1101 		drm_info(display->drm, "Disabling DMC firmware and runtime PM\n");
1102 		goto out;
1103 	}
1104 
1105 	if (dmc_firmware_param(display))
1106 		dmc->fw_path = dmc_firmware_param(display);
1107 
1108 	if (!dmc->fw_path) {
1109 		drm_dbg_kms(display->drm,
1110 			    "No known DMC firmware for platform, disabling runtime PM\n");
1111 		goto out;
1112 	}
1113 
1114 	display->dmc.dmc = dmc;
1115 
1116 	drm_dbg_kms(display->drm, "Loading %s\n", dmc->fw_path);
1117 	queue_work(i915->unordered_wq, &dmc->work);
1118 
1119 	return;
1120 
1121 out:
1122 	kfree(dmc);
1123 }
1124 
1125 /**
1126  * intel_dmc_suspend() - prepare DMC firmware before system suspend
1127  * @display: display instance
1128  *
1129  * Prepare the DMC firmware before entering system suspend. This includes
1130  * flushing pending work items and releasing any resources acquired during
1131  * init.
1132  */
1133 void intel_dmc_suspend(struct intel_display *display)
1134 {
1135 	struct intel_dmc *dmc = display_to_dmc(display);
1136 
1137 	if (!HAS_DMC(display))
1138 		return;
1139 
1140 	if (dmc)
1141 		flush_work(&dmc->work);
1142 
1143 	intel_dmc_wl_disable(display);
1144 
1145 	/* Drop the reference held in case DMC isn't loaded. */
1146 	if (!intel_dmc_has_payload(display))
1147 		intel_dmc_runtime_pm_put(display);
1148 }
1149 
1150 /**
1151  * intel_dmc_resume() - init DMC firmware during system resume
1152  * @display: display instance
1153  *
1154  * Reinitialize the DMC firmware during system resume, reacquiring any
1155  * resources released in intel_dmc_suspend().
1156  */
1157 void intel_dmc_resume(struct intel_display *display)
1158 {
1159 	if (!HAS_DMC(display))
1160 		return;
1161 
1162 	/*
1163 	 * Reacquire the reference to keep RPM disabled in case DMC isn't
1164 	 * loaded.
1165 	 */
1166 	if (!intel_dmc_has_payload(display))
1167 		intel_dmc_runtime_pm_get(display);
1168 }
1169 
1170 /**
1171  * intel_dmc_fini() - unload the DMC firmware.
1172  * @display: display instance
1173  *
1174  * Firmmware unloading includes freeing the internal memory and reset the
1175  * firmware loading status.
1176  */
1177 void intel_dmc_fini(struct intel_display *display)
1178 {
1179 	struct intel_dmc *dmc = display_to_dmc(display);
1180 	enum intel_dmc_id dmc_id;
1181 
1182 	if (!HAS_DMC(display))
1183 		return;
1184 
1185 	intel_dmc_suspend(display);
1186 	drm_WARN_ON(display->drm, display->dmc.wakeref);
1187 
1188 	if (dmc) {
1189 		for_each_dmc_id(dmc_id)
1190 			kfree(dmc->dmc_info[dmc_id].payload);
1191 
1192 		kfree(dmc);
1193 		display->dmc.dmc = NULL;
1194 	}
1195 }
1196 
1197 struct intel_dmc_snapshot {
1198 	bool initialized;
1199 	bool loaded;
1200 	u32 version;
1201 };
1202 
1203 struct intel_dmc_snapshot *intel_dmc_snapshot_capture(struct intel_display *display)
1204 {
1205 	struct intel_dmc *dmc = display_to_dmc(display);
1206 	struct intel_dmc_snapshot *snapshot;
1207 
1208 	if (!HAS_DMC(display))
1209 		return NULL;
1210 
1211 	snapshot = kzalloc(sizeof(*snapshot), GFP_ATOMIC);
1212 	if (!snapshot)
1213 		return NULL;
1214 
1215 	snapshot->initialized = dmc;
1216 	snapshot->loaded = intel_dmc_has_payload(display);
1217 	if (dmc)
1218 		snapshot->version = dmc->version;
1219 
1220 	return snapshot;
1221 }
1222 
1223 void intel_dmc_snapshot_print(const struct intel_dmc_snapshot *snapshot, struct drm_printer *p)
1224 {
1225 	if (!snapshot)
1226 		return;
1227 
1228 	drm_printf(p, "DMC initialized: %s\n", str_yes_no(snapshot->initialized));
1229 	drm_printf(p, "DMC loaded: %s\n", str_yes_no(snapshot->loaded));
1230 	if (snapshot->initialized)
1231 		drm_printf(p, "DMC fw version: %d.%d\n",
1232 			   DMC_VERSION_MAJOR(snapshot->version),
1233 			   DMC_VERSION_MINOR(snapshot->version));
1234 }
1235 
1236 static int intel_dmc_debugfs_status_show(struct seq_file *m, void *unused)
1237 {
1238 	struct intel_display *display = m->private;
1239 	struct drm_i915_private *i915 = to_i915(display->drm);
1240 	struct intel_dmc *dmc = display_to_dmc(display);
1241 	intel_wakeref_t wakeref;
1242 	i915_reg_t dc5_reg, dc6_reg = INVALID_MMIO_REG;
1243 
1244 	if (!HAS_DMC(display))
1245 		return -ENODEV;
1246 
1247 	wakeref = intel_runtime_pm_get(&i915->runtime_pm);
1248 
1249 	seq_printf(m, "DMC initialized: %s\n", str_yes_no(dmc));
1250 	seq_printf(m, "fw loaded: %s\n",
1251 		   str_yes_no(intel_dmc_has_payload(display)));
1252 	seq_printf(m, "path: %s\n", dmc ? dmc->fw_path : "N/A");
1253 	seq_printf(m, "Pipe A fw needed: %s\n",
1254 		   str_yes_no(DISPLAY_VER(display) >= 12));
1255 	seq_printf(m, "Pipe A fw loaded: %s\n",
1256 		   str_yes_no(has_dmc_id_fw(display, DMC_FW_PIPEA)));
1257 	seq_printf(m, "Pipe B fw needed: %s\n",
1258 		   str_yes_no(IS_ALDERLAKE_P(i915) ||
1259 			      DISPLAY_VER(display) >= 14));
1260 	seq_printf(m, "Pipe B fw loaded: %s\n",
1261 		   str_yes_no(has_dmc_id_fw(display, DMC_FW_PIPEB)));
1262 
1263 	if (!intel_dmc_has_payload(display))
1264 		goto out;
1265 
1266 	seq_printf(m, "version: %d.%d\n", DMC_VERSION_MAJOR(dmc->version),
1267 		   DMC_VERSION_MINOR(dmc->version));
1268 
1269 	if (DISPLAY_VER(display) >= 12) {
1270 		i915_reg_t dc3co_reg;
1271 
1272 		if (IS_DGFX(i915) || DISPLAY_VER(display) >= 14) {
1273 			dc3co_reg = DG1_DMC_DEBUG3;
1274 			dc5_reg = DG1_DMC_DEBUG_DC5_COUNT;
1275 		} else {
1276 			dc3co_reg = TGL_DMC_DEBUG3;
1277 			dc5_reg = TGL_DMC_DEBUG_DC5_COUNT;
1278 			dc6_reg = TGL_DMC_DEBUG_DC6_COUNT;
1279 		}
1280 
1281 		seq_printf(m, "DC3CO count: %d\n",
1282 			   intel_de_read(display, dc3co_reg));
1283 	} else {
1284 		dc5_reg = IS_BROXTON(i915) ? BXT_DMC_DC3_DC5_COUNT :
1285 			SKL_DMC_DC3_DC5_COUNT;
1286 		if (!IS_GEMINILAKE(i915) && !IS_BROXTON(i915))
1287 			dc6_reg = SKL_DMC_DC5_DC6_COUNT;
1288 	}
1289 
1290 	seq_printf(m, "DC3 -> DC5 count: %d\n", intel_de_read(display, dc5_reg));
1291 	if (i915_mmio_reg_valid(dc6_reg))
1292 		seq_printf(m, "DC5 -> DC6 count: %d\n",
1293 			   intel_de_read(display, dc6_reg));
1294 
1295 	seq_printf(m, "program base: 0x%08x\n",
1296 		   intel_de_read(display, DMC_PROGRAM(dmc->dmc_info[DMC_FW_MAIN].start_mmioaddr, 0)));
1297 
1298 out:
1299 	seq_printf(m, "ssp base: 0x%08x\n",
1300 		   intel_de_read(display, DMC_SSP_BASE));
1301 	seq_printf(m, "htp: 0x%08x\n", intel_de_read(display, DMC_HTP_SKL));
1302 
1303 	intel_runtime_pm_put(&i915->runtime_pm, wakeref);
1304 
1305 	return 0;
1306 }
1307 
1308 DEFINE_SHOW_ATTRIBUTE(intel_dmc_debugfs_status);
1309 
1310 void intel_dmc_debugfs_register(struct intel_display *display)
1311 {
1312 	struct drm_minor *minor = display->drm->primary;
1313 
1314 	debugfs_create_file("i915_dmc_info", 0444, minor->debugfs_root,
1315 			    display, &intel_dmc_debugfs_status_fops);
1316 }
1317