xref: /openbmc/linux/drivers/gpu/drm/i915/gt/intel_rc6.c (revision 29d97219)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2019 Intel Corporation
4  */
5 
6 #include <linux/pm_runtime.h>
7 
8 #include "i915_drv.h"
9 #include "i915_vgpu.h"
10 #include "intel_gt.h"
11 #include "intel_gt_pm.h"
12 #include "intel_rc6.h"
13 #include "intel_sideband.h"
14 
15 /**
16  * DOC: RC6
17  *
18  * RC6 is a special power stage which allows the GPU to enter an very
19  * low-voltage mode when idle, using down to 0V while at this stage.  This
20  * stage is entered automatically when the GPU is idle when RC6 support is
21  * enabled, and as soon as new workload arises GPU wakes up automatically as
22  * well.
23  *
24  * There are different RC6 modes available in Intel GPU, which differentiate
25  * among each other with the latency required to enter and leave RC6 and
26  * voltage consumed by the GPU in different states.
27  *
28  * The combination of the following flags define which states GPU is allowed
29  * to enter, while RC6 is the normal RC6 state, RC6p is the deep RC6, and
30  * RC6pp is deepest RC6. Their support by hardware varies according to the
31  * GPU, BIOS, chipset and platform. RC6 is usually the safest one and the one
32  * which brings the most power savings; deeper states save more power, but
33  * require higher latency to switch to and wake up.
34  */
35 
36 static struct intel_gt *rc6_to_gt(struct intel_rc6 *rc6)
37 {
38 	return container_of(rc6, struct intel_gt, rc6);
39 }
40 
41 static struct intel_uncore *rc6_to_uncore(struct intel_rc6 *rc)
42 {
43 	return rc6_to_gt(rc)->uncore;
44 }
45 
46 static struct drm_i915_private *rc6_to_i915(struct intel_rc6 *rc)
47 {
48 	return rc6_to_gt(rc)->i915;
49 }
50 
51 static void set(struct intel_uncore *uncore, i915_reg_t reg, u32 val)
52 {
53 	intel_uncore_write_fw(uncore, reg, val);
54 }
55 
56 static void gen11_rc6_enable(struct intel_rc6 *rc6)
57 {
58 	struct intel_gt *gt = rc6_to_gt(rc6);
59 	struct intel_uncore *uncore = gt->uncore;
60 	struct intel_engine_cs *engine;
61 	enum intel_engine_id id;
62 	u32 pg_enable;
63 	int i;
64 
65 	/* 2b: Program RC6 thresholds.*/
66 	set(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 54 << 16 | 85);
67 	set(uncore, GEN10_MEDIA_WAKE_RATE_LIMIT, 150);
68 
69 	set(uncore, GEN6_RC_EVALUATION_INTERVAL, 125000); /* 12500 * 1280ns */
70 	set(uncore, GEN6_RC_IDLE_HYSTERSIS, 25); /* 25 * 1280ns */
71 	for_each_engine(engine, rc6_to_gt(rc6), id)
72 		set(uncore, RING_MAX_IDLE(engine->mmio_base), 10);
73 
74 	set(uncore, GUC_MAX_IDLE_COUNT, 0xA);
75 
76 	set(uncore, GEN6_RC_SLEEP, 0);
77 
78 	set(uncore, GEN6_RC6_THRESHOLD, 50000); /* 50/125ms per EI */
79 
80 	/*
81 	 * 2c: Program Coarse Power Gating Policies.
82 	 *
83 	 * Bspec's guidance is to use 25us (really 25 * 1280ns) here. What we
84 	 * use instead is a more conservative estimate for the maximum time
85 	 * it takes us to service a CS interrupt and submit a new ELSP - that
86 	 * is the time which the GPU is idle waiting for the CPU to select the
87 	 * next request to execute. If the idle hysteresis is less than that
88 	 * interrupt service latency, the hardware will automatically gate
89 	 * the power well and we will then incur the wake up cost on top of
90 	 * the service latency. A similar guide from plane_state is that we
91 	 * do not want the enable hysteresis to less than the wakeup latency.
92 	 *
93 	 * igt/gem_exec_nop/sequential provides a rough estimate for the
94 	 * service latency, and puts it under 10us for Icelake, similar to
95 	 * Broadwell+, To be conservative, we want to factor in a context
96 	 * switch on top (due to ksoftirqd).
97 	 */
98 	set(uncore, GEN9_MEDIA_PG_IDLE_HYSTERESIS, 60);
99 	set(uncore, GEN9_RENDER_PG_IDLE_HYSTERESIS, 60);
100 
101 	/* 3a: Enable RC6 */
102 	rc6->ctl_enable =
103 		GEN6_RC_CTL_HW_ENABLE |
104 		GEN6_RC_CTL_RC6_ENABLE |
105 		GEN6_RC_CTL_EI_MODE(1);
106 
107 	pg_enable =
108 		GEN9_RENDER_PG_ENABLE |
109 		GEN9_MEDIA_PG_ENABLE |
110 		GEN11_MEDIA_SAMPLER_PG_ENABLE;
111 
112 	if (INTEL_GEN(gt->i915) >= 12) {
113 		for (i = 0; i < I915_MAX_VCS; i++)
114 			if (HAS_ENGINE(gt, _VCS(i)))
115 				pg_enable |= (VDN_HCP_POWERGATE_ENABLE(i) |
116 					      VDN_MFX_POWERGATE_ENABLE(i));
117 	}
118 
119 	set(uncore, GEN9_PG_ENABLE, pg_enable);
120 }
121 
122 static void gen9_rc6_enable(struct intel_rc6 *rc6)
123 {
124 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
125 	struct intel_engine_cs *engine;
126 	enum intel_engine_id id;
127 
128 	/* 2b: Program RC6 thresholds.*/
129 	if (INTEL_GEN(rc6_to_i915(rc6)) >= 10) {
130 		set(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 54 << 16 | 85);
131 		set(uncore, GEN10_MEDIA_WAKE_RATE_LIMIT, 150);
132 	} else if (IS_SKYLAKE(rc6_to_i915(rc6))) {
133 		/*
134 		 * WaRsDoubleRc6WrlWithCoarsePowerGating:skl Doubling WRL only
135 		 * when CPG is enabled
136 		 */
137 		set(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 108 << 16);
138 	} else {
139 		set(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 54 << 16);
140 	}
141 
142 	set(uncore, GEN6_RC_EVALUATION_INTERVAL, 125000); /* 12500 * 1280ns */
143 	set(uncore, GEN6_RC_IDLE_HYSTERSIS, 25); /* 25 * 1280ns */
144 	for_each_engine(engine, rc6_to_gt(rc6), id)
145 		set(uncore, RING_MAX_IDLE(engine->mmio_base), 10);
146 
147 	set(uncore, GUC_MAX_IDLE_COUNT, 0xA);
148 
149 	set(uncore, GEN6_RC_SLEEP, 0);
150 
151 	/*
152 	 * 2c: Program Coarse Power Gating Policies.
153 	 *
154 	 * Bspec's guidance is to use 25us (really 25 * 1280ns) here. What we
155 	 * use instead is a more conservative estimate for the maximum time
156 	 * it takes us to service a CS interrupt and submit a new ELSP - that
157 	 * is the time which the GPU is idle waiting for the CPU to select the
158 	 * next request to execute. If the idle hysteresis is less than that
159 	 * interrupt service latency, the hardware will automatically gate
160 	 * the power well and we will then incur the wake up cost on top of
161 	 * the service latency. A similar guide from plane_state is that we
162 	 * do not want the enable hysteresis to less than the wakeup latency.
163 	 *
164 	 * igt/gem_exec_nop/sequential provides a rough estimate for the
165 	 * service latency, and puts it around 10us for Broadwell (and other
166 	 * big core) and around 40us for Broxton (and other low power cores).
167 	 * [Note that for legacy ringbuffer submission, this is less than 1us!]
168 	 * However, the wakeup latency on Broxton is closer to 100us. To be
169 	 * conservative, we have to factor in a context switch on top (due
170 	 * to ksoftirqd).
171 	 */
172 	set(uncore, GEN9_MEDIA_PG_IDLE_HYSTERESIS, 250);
173 	set(uncore, GEN9_RENDER_PG_IDLE_HYSTERESIS, 250);
174 
175 	/* 3a: Enable RC6 */
176 	set(uncore, GEN6_RC6_THRESHOLD, 37500); /* 37.5/125ms per EI */
177 
178 	rc6->ctl_enable =
179 		GEN6_RC_CTL_HW_ENABLE |
180 		GEN6_RC_CTL_RC6_ENABLE |
181 		GEN6_RC_CTL_EI_MODE(1);
182 
183 	/*
184 	 * WaRsDisableCoarsePowerGating:skl,cnl
185 	 *   - Render/Media PG need to be disabled with RC6.
186 	 */
187 	if (!NEEDS_WaRsDisableCoarsePowerGating(rc6_to_i915(rc6)))
188 		set(uncore, GEN9_PG_ENABLE,
189 		    GEN9_RENDER_PG_ENABLE | GEN9_MEDIA_PG_ENABLE);
190 }
191 
192 static void gen8_rc6_enable(struct intel_rc6 *rc6)
193 {
194 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
195 	struct intel_engine_cs *engine;
196 	enum intel_engine_id id;
197 
198 	/* 2b: Program RC6 thresholds.*/
199 	set(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 40 << 16);
200 	set(uncore, GEN6_RC_EVALUATION_INTERVAL, 125000); /* 12500 * 1280ns */
201 	set(uncore, GEN6_RC_IDLE_HYSTERSIS, 25); /* 25 * 1280ns */
202 	for_each_engine(engine, rc6_to_gt(rc6), id)
203 		set(uncore, RING_MAX_IDLE(engine->mmio_base), 10);
204 	set(uncore, GEN6_RC_SLEEP, 0);
205 	set(uncore, GEN6_RC6_THRESHOLD, 625); /* 800us/1.28 for TO */
206 
207 	/* 3: Enable RC6 */
208 	rc6->ctl_enable =
209 	    GEN6_RC_CTL_HW_ENABLE |
210 	    GEN7_RC_CTL_TO_MODE |
211 	    GEN6_RC_CTL_RC6_ENABLE;
212 }
213 
214 static void gen6_rc6_enable(struct intel_rc6 *rc6)
215 {
216 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
217 	struct drm_i915_private *i915 = rc6_to_i915(rc6);
218 	struct intel_engine_cs *engine;
219 	enum intel_engine_id id;
220 	u32 rc6vids, rc6_mask;
221 	int ret;
222 
223 	set(uncore, GEN6_RC1_WAKE_RATE_LIMIT, 1000 << 16);
224 	set(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 40 << 16 | 30);
225 	set(uncore, GEN6_RC6pp_WAKE_RATE_LIMIT, 30);
226 	set(uncore, GEN6_RC_EVALUATION_INTERVAL, 125000);
227 	set(uncore, GEN6_RC_IDLE_HYSTERSIS, 25);
228 
229 	for_each_engine(engine, rc6_to_gt(rc6), id)
230 		set(uncore, RING_MAX_IDLE(engine->mmio_base), 10);
231 
232 	set(uncore, GEN6_RC_SLEEP, 0);
233 	set(uncore, GEN6_RC1e_THRESHOLD, 1000);
234 	set(uncore, GEN6_RC6_THRESHOLD, 50000);
235 	set(uncore, GEN6_RC6p_THRESHOLD, 150000);
236 	set(uncore, GEN6_RC6pp_THRESHOLD, 64000); /* unused */
237 
238 	/* We don't use those on Haswell */
239 	rc6_mask = GEN6_RC_CTL_RC6_ENABLE;
240 	if (HAS_RC6p(i915))
241 		rc6_mask |= GEN6_RC_CTL_RC6p_ENABLE;
242 	if (HAS_RC6pp(i915))
243 		rc6_mask |= GEN6_RC_CTL_RC6pp_ENABLE;
244 	rc6->ctl_enable =
245 	    rc6_mask |
246 	    GEN6_RC_CTL_EI_MODE(1) |
247 	    GEN6_RC_CTL_HW_ENABLE;
248 
249 	rc6vids = 0;
250 	ret = sandybridge_pcode_read(i915, GEN6_PCODE_READ_RC6VIDS,
251 				     &rc6vids, NULL);
252 	if (IS_GEN(i915, 6) && ret) {
253 		drm_dbg(&i915->drm, "Couldn't check for BIOS workaround\n");
254 	} else if (IS_GEN(i915, 6) &&
255 		   (GEN6_DECODE_RC6_VID(rc6vids & 0xff) < 450)) {
256 		drm_dbg(&i915->drm,
257 			"You should update your BIOS. Correcting minimum rc6 voltage (%dmV->%dmV)\n",
258 			GEN6_DECODE_RC6_VID(rc6vids & 0xff), 450);
259 		rc6vids &= 0xffff00;
260 		rc6vids |= GEN6_ENCODE_RC6_VID(450);
261 		ret = sandybridge_pcode_write(i915, GEN6_PCODE_WRITE_RC6VIDS, rc6vids);
262 		if (ret)
263 			drm_err(&i915->drm,
264 				"Couldn't fix incorrect rc6 voltage\n");
265 	}
266 }
267 
268 /* Check that the pcbr address is not empty. */
269 static int chv_rc6_init(struct intel_rc6 *rc6)
270 {
271 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
272 	struct drm_i915_private *i915 = rc6_to_i915(rc6);
273 	resource_size_t pctx_paddr, paddr;
274 	resource_size_t pctx_size = 32 * SZ_1K;
275 	u32 pcbr;
276 
277 	pcbr = intel_uncore_read(uncore, VLV_PCBR);
278 	if ((pcbr >> VLV_PCBR_ADDR_SHIFT) == 0) {
279 		drm_dbg(&i915->drm, "BIOS didn't set up PCBR, fixing up\n");
280 		paddr = i915->dsm.end + 1 - pctx_size;
281 		GEM_BUG_ON(paddr > U32_MAX);
282 
283 		pctx_paddr = (paddr & ~4095);
284 		intel_uncore_write(uncore, VLV_PCBR, pctx_paddr);
285 	}
286 
287 	return 0;
288 }
289 
290 static int vlv_rc6_init(struct intel_rc6 *rc6)
291 {
292 	struct drm_i915_private *i915 = rc6_to_i915(rc6);
293 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
294 	struct drm_i915_gem_object *pctx;
295 	resource_size_t pctx_paddr;
296 	resource_size_t pctx_size = 24 * SZ_1K;
297 	u32 pcbr;
298 
299 	pcbr = intel_uncore_read(uncore, VLV_PCBR);
300 	if (pcbr) {
301 		/* BIOS set it up already, grab the pre-alloc'd space */
302 		resource_size_t pcbr_offset;
303 
304 		pcbr_offset = (pcbr & ~4095) - i915->dsm.start;
305 		pctx = i915_gem_object_create_stolen_for_preallocated(i915,
306 								      pcbr_offset,
307 								      pctx_size);
308 		if (IS_ERR(pctx))
309 			return PTR_ERR(pctx);
310 
311 		goto out;
312 	}
313 
314 	drm_dbg(&i915->drm, "BIOS didn't set up PCBR, fixing up\n");
315 
316 	/*
317 	 * From the Gunit register HAS:
318 	 * The Gfx driver is expected to program this register and ensure
319 	 * proper allocation within Gfx stolen memory.  For example, this
320 	 * register should be programmed such than the PCBR range does not
321 	 * overlap with other ranges, such as the frame buffer, protected
322 	 * memory, or any other relevant ranges.
323 	 */
324 	pctx = i915_gem_object_create_stolen(i915, pctx_size);
325 	if (IS_ERR(pctx)) {
326 		drm_dbg(&i915->drm,
327 			"not enough stolen space for PCTX, disabling\n");
328 		return PTR_ERR(pctx);
329 	}
330 
331 	GEM_BUG_ON(range_overflows_end_t(u64,
332 					 i915->dsm.start,
333 					 pctx->stolen->start,
334 					 U32_MAX));
335 	pctx_paddr = i915->dsm.start + pctx->stolen->start;
336 	intel_uncore_write(uncore, VLV_PCBR, pctx_paddr);
337 
338 out:
339 	rc6->pctx = pctx;
340 	return 0;
341 }
342 
343 static void chv_rc6_enable(struct intel_rc6 *rc6)
344 {
345 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
346 	struct intel_engine_cs *engine;
347 	enum intel_engine_id id;
348 
349 	/* 2a: Program RC6 thresholds.*/
350 	set(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 40 << 16);
351 	set(uncore, GEN6_RC_EVALUATION_INTERVAL, 125000); /* 12500 * 1280ns */
352 	set(uncore, GEN6_RC_IDLE_HYSTERSIS, 25); /* 25 * 1280ns */
353 
354 	for_each_engine(engine, rc6_to_gt(rc6), id)
355 		set(uncore, RING_MAX_IDLE(engine->mmio_base), 10);
356 	set(uncore, GEN6_RC_SLEEP, 0);
357 
358 	/* TO threshold set to 500 us (0x186 * 1.28 us) */
359 	set(uncore, GEN6_RC6_THRESHOLD, 0x186);
360 
361 	/* Allows RC6 residency counter to work */
362 	set(uncore, VLV_COUNTER_CONTROL,
363 	    _MASKED_BIT_ENABLE(VLV_COUNT_RANGE_HIGH |
364 			       VLV_MEDIA_RC6_COUNT_EN |
365 			       VLV_RENDER_RC6_COUNT_EN));
366 
367 	/* 3: Enable RC6 */
368 	rc6->ctl_enable = GEN7_RC_CTL_TO_MODE;
369 }
370 
371 static void vlv_rc6_enable(struct intel_rc6 *rc6)
372 {
373 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
374 	struct intel_engine_cs *engine;
375 	enum intel_engine_id id;
376 
377 	set(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 0x00280000);
378 	set(uncore, GEN6_RC_EVALUATION_INTERVAL, 125000);
379 	set(uncore, GEN6_RC_IDLE_HYSTERSIS, 25);
380 
381 	for_each_engine(engine, rc6_to_gt(rc6), id)
382 		set(uncore, RING_MAX_IDLE(engine->mmio_base), 10);
383 
384 	set(uncore, GEN6_RC6_THRESHOLD, 0x557);
385 
386 	/* Allows RC6 residency counter to work */
387 	set(uncore, VLV_COUNTER_CONTROL,
388 	    _MASKED_BIT_ENABLE(VLV_COUNT_RANGE_HIGH |
389 			       VLV_MEDIA_RC0_COUNT_EN |
390 			       VLV_RENDER_RC0_COUNT_EN |
391 			       VLV_MEDIA_RC6_COUNT_EN |
392 			       VLV_RENDER_RC6_COUNT_EN));
393 
394 	rc6->ctl_enable =
395 	    GEN7_RC_CTL_TO_MODE | VLV_RC_CTL_CTX_RST_PARALLEL;
396 }
397 
398 static bool bxt_check_bios_rc6_setup(struct intel_rc6 *rc6)
399 {
400 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
401 	struct drm_i915_private *i915 = rc6_to_i915(rc6);
402 	u32 rc6_ctx_base, rc_ctl, rc_sw_target;
403 	bool enable_rc6 = true;
404 
405 	rc_ctl = intel_uncore_read(uncore, GEN6_RC_CONTROL);
406 	rc_sw_target = intel_uncore_read(uncore, GEN6_RC_STATE);
407 	rc_sw_target &= RC_SW_TARGET_STATE_MASK;
408 	rc_sw_target >>= RC_SW_TARGET_STATE_SHIFT;
409 	drm_dbg(&i915->drm, "BIOS enabled RC states: "
410 			 "HW_CTRL %s HW_RC6 %s SW_TARGET_STATE %x\n",
411 			 onoff(rc_ctl & GEN6_RC_CTL_HW_ENABLE),
412 			 onoff(rc_ctl & GEN6_RC_CTL_RC6_ENABLE),
413 			 rc_sw_target);
414 
415 	if (!(intel_uncore_read(uncore, RC6_LOCATION) & RC6_CTX_IN_DRAM)) {
416 		drm_dbg(&i915->drm, "RC6 Base location not set properly.\n");
417 		enable_rc6 = false;
418 	}
419 
420 	/*
421 	 * The exact context size is not known for BXT, so assume a page size
422 	 * for this check.
423 	 */
424 	rc6_ctx_base =
425 		intel_uncore_read(uncore, RC6_CTX_BASE) & RC6_CTX_BASE_MASK;
426 	if (!(rc6_ctx_base >= i915->dsm_reserved.start &&
427 	      rc6_ctx_base + PAGE_SIZE < i915->dsm_reserved.end)) {
428 		drm_dbg(&i915->drm, "RC6 Base address not as expected.\n");
429 		enable_rc6 = false;
430 	}
431 
432 	if (!((intel_uncore_read(uncore, PWRCTX_MAXCNT_RCSUNIT) & IDLE_TIME_MASK) > 1 &&
433 	      (intel_uncore_read(uncore, PWRCTX_MAXCNT_VCSUNIT0) & IDLE_TIME_MASK) > 1 &&
434 	      (intel_uncore_read(uncore, PWRCTX_MAXCNT_BCSUNIT) & IDLE_TIME_MASK) > 1 &&
435 	      (intel_uncore_read(uncore, PWRCTX_MAXCNT_VECSUNIT) & IDLE_TIME_MASK) > 1)) {
436 		drm_dbg(&i915->drm,
437 			"Engine Idle wait time not set properly.\n");
438 		enable_rc6 = false;
439 	}
440 
441 	if (!intel_uncore_read(uncore, GEN8_PUSHBUS_CONTROL) ||
442 	    !intel_uncore_read(uncore, GEN8_PUSHBUS_ENABLE) ||
443 	    !intel_uncore_read(uncore, GEN8_PUSHBUS_SHIFT)) {
444 		drm_dbg(&i915->drm, "Pushbus not setup properly.\n");
445 		enable_rc6 = false;
446 	}
447 
448 	if (!intel_uncore_read(uncore, GEN6_GFXPAUSE)) {
449 		drm_dbg(&i915->drm, "GFX pause not setup properly.\n");
450 		enable_rc6 = false;
451 	}
452 
453 	if (!intel_uncore_read(uncore, GEN8_MISC_CTRL0)) {
454 		drm_dbg(&i915->drm, "GPM control not setup properly.\n");
455 		enable_rc6 = false;
456 	}
457 
458 	return enable_rc6;
459 }
460 
461 static bool rc6_supported(struct intel_rc6 *rc6)
462 {
463 	struct drm_i915_private *i915 = rc6_to_i915(rc6);
464 
465 	if (!HAS_RC6(i915))
466 		return false;
467 
468 	if (intel_vgpu_active(i915))
469 		return false;
470 
471 	if (is_mock_gt(rc6_to_gt(rc6)))
472 		return false;
473 
474 	if (IS_GEN9_LP(i915) && !bxt_check_bios_rc6_setup(rc6)) {
475 		drm_notice(&i915->drm,
476 			   "RC6 and powersaving disabled by BIOS\n");
477 		return false;
478 	}
479 
480 	return true;
481 }
482 
483 static void rpm_get(struct intel_rc6 *rc6)
484 {
485 	GEM_BUG_ON(rc6->wakeref);
486 	pm_runtime_get_sync(rc6_to_i915(rc6)->drm.dev);
487 	rc6->wakeref = true;
488 }
489 
490 static void rpm_put(struct intel_rc6 *rc6)
491 {
492 	GEM_BUG_ON(!rc6->wakeref);
493 	pm_runtime_put(rc6_to_i915(rc6)->drm.dev);
494 	rc6->wakeref = false;
495 }
496 
497 static bool pctx_corrupted(struct intel_rc6 *rc6)
498 {
499 	struct drm_i915_private *i915 = rc6_to_i915(rc6);
500 
501 	if (!NEEDS_RC6_CTX_CORRUPTION_WA(i915))
502 		return false;
503 
504 	if (intel_uncore_read(rc6_to_uncore(rc6), GEN8_RC6_CTX_INFO))
505 		return false;
506 
507 	drm_notice(&i915->drm,
508 		   "RC6 context corruption, disabling runtime power management\n");
509 	return true;
510 }
511 
512 static void __intel_rc6_disable(struct intel_rc6 *rc6)
513 {
514 	struct drm_i915_private *i915 = rc6_to_i915(rc6);
515 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
516 
517 	intel_uncore_forcewake_get(uncore, FORCEWAKE_ALL);
518 	if (INTEL_GEN(i915) >= 9)
519 		set(uncore, GEN9_PG_ENABLE, 0);
520 	set(uncore, GEN6_RC_CONTROL, 0);
521 	set(uncore, GEN6_RC_STATE, 0);
522 	intel_uncore_forcewake_put(uncore, FORCEWAKE_ALL);
523 }
524 
525 void intel_rc6_init(struct intel_rc6 *rc6)
526 {
527 	struct drm_i915_private *i915 = rc6_to_i915(rc6);
528 	int err;
529 
530 	/* Disable runtime-pm until we can save the GPU state with rc6 pctx */
531 	rpm_get(rc6);
532 
533 	if (!rc6_supported(rc6))
534 		return;
535 
536 	if (IS_CHERRYVIEW(i915))
537 		err = chv_rc6_init(rc6);
538 	else if (IS_VALLEYVIEW(i915))
539 		err = vlv_rc6_init(rc6);
540 	else
541 		err = 0;
542 
543 	/* Sanitize rc6, ensure it is disabled before we are ready. */
544 	__intel_rc6_disable(rc6);
545 
546 	rc6->supported = err == 0;
547 }
548 
549 void intel_rc6_sanitize(struct intel_rc6 *rc6)
550 {
551 	memset(rc6->prev_hw_residency, 0, sizeof(rc6->prev_hw_residency));
552 
553 	if (rc6->enabled) { /* unbalanced suspend/resume */
554 		rpm_get(rc6);
555 		rc6->enabled = false;
556 	}
557 
558 	if (rc6->supported)
559 		__intel_rc6_disable(rc6);
560 }
561 
562 void intel_rc6_enable(struct intel_rc6 *rc6)
563 {
564 	struct drm_i915_private *i915 = rc6_to_i915(rc6);
565 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
566 
567 	if (!rc6->supported)
568 		return;
569 
570 	GEM_BUG_ON(rc6->enabled);
571 
572 	intel_uncore_forcewake_get(uncore, FORCEWAKE_ALL);
573 
574 	if (IS_CHERRYVIEW(i915))
575 		chv_rc6_enable(rc6);
576 	else if (IS_VALLEYVIEW(i915))
577 		vlv_rc6_enable(rc6);
578 	else if (INTEL_GEN(i915) >= 11)
579 		gen11_rc6_enable(rc6);
580 	else if (INTEL_GEN(i915) >= 9)
581 		gen9_rc6_enable(rc6);
582 	else if (IS_BROADWELL(i915))
583 		gen8_rc6_enable(rc6);
584 	else if (INTEL_GEN(i915) >= 6)
585 		gen6_rc6_enable(rc6);
586 
587 	rc6->manual = rc6->ctl_enable & GEN6_RC_CTL_RC6_ENABLE;
588 	if (NEEDS_RC6_CTX_CORRUPTION_WA(i915))
589 		rc6->ctl_enable = 0;
590 
591 	intel_uncore_forcewake_put(uncore, FORCEWAKE_ALL);
592 
593 	if (unlikely(pctx_corrupted(rc6)))
594 		return;
595 
596 	/* rc6 is ready, runtime-pm is go! */
597 	rpm_put(rc6);
598 	rc6->enabled = true;
599 }
600 
601 void intel_rc6_unpark(struct intel_rc6 *rc6)
602 {
603 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
604 
605 	if (!rc6->enabled)
606 		return;
607 
608 	/* Restore HW timers for automatic RC6 entry while busy */
609 	set(uncore, GEN6_RC_CONTROL, rc6->ctl_enable);
610 }
611 
612 void intel_rc6_park(struct intel_rc6 *rc6)
613 {
614 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
615 	unsigned int target;
616 
617 	if (!rc6->enabled)
618 		return;
619 
620 	if (unlikely(pctx_corrupted(rc6))) {
621 		intel_rc6_disable(rc6);
622 		return;
623 	}
624 
625 	if (!rc6->manual)
626 		return;
627 
628 	/* Turn off the HW timers and go directly to rc6 */
629 	set(uncore, GEN6_RC_CONTROL, GEN6_RC_CTL_RC6_ENABLE);
630 
631 	if (HAS_RC6pp(rc6_to_i915(rc6)))
632 		target = 0x6; /* deepest rc6 */
633 	else if (HAS_RC6p(rc6_to_i915(rc6)))
634 		target = 0x5; /* deep rc6 */
635 	else
636 		target = 0x4; /* normal rc6 */
637 	set(uncore, GEN6_RC_STATE, target << RC_SW_TARGET_STATE_SHIFT);
638 }
639 
640 void intel_rc6_disable(struct intel_rc6 *rc6)
641 {
642 	if (!rc6->enabled)
643 		return;
644 
645 	rpm_get(rc6);
646 	rc6->enabled = false;
647 
648 	__intel_rc6_disable(rc6);
649 }
650 
651 void intel_rc6_fini(struct intel_rc6 *rc6)
652 {
653 	struct drm_i915_gem_object *pctx;
654 
655 	intel_rc6_disable(rc6);
656 
657 	pctx = fetch_and_zero(&rc6->pctx);
658 	if (pctx)
659 		i915_gem_object_put(pctx);
660 
661 	if (rc6->wakeref)
662 		rpm_put(rc6);
663 }
664 
665 static u64 vlv_residency_raw(struct intel_uncore *uncore, const i915_reg_t reg)
666 {
667 	u32 lower, upper, tmp;
668 	int loop = 2;
669 
670 	/*
671 	 * The register accessed do not need forcewake. We borrow
672 	 * uncore lock to prevent concurrent access to range reg.
673 	 */
674 	lockdep_assert_held(&uncore->lock);
675 
676 	/*
677 	 * vlv and chv residency counters are 40 bits in width.
678 	 * With a control bit, we can choose between upper or lower
679 	 * 32bit window into this counter.
680 	 *
681 	 * Although we always use the counter in high-range mode elsewhere,
682 	 * userspace may attempt to read the value before rc6 is initialised,
683 	 * before we have set the default VLV_COUNTER_CONTROL value. So always
684 	 * set the high bit to be safe.
685 	 */
686 	set(uncore, VLV_COUNTER_CONTROL,
687 	    _MASKED_BIT_ENABLE(VLV_COUNT_RANGE_HIGH));
688 	upper = intel_uncore_read_fw(uncore, reg);
689 	do {
690 		tmp = upper;
691 
692 		set(uncore, VLV_COUNTER_CONTROL,
693 		    _MASKED_BIT_DISABLE(VLV_COUNT_RANGE_HIGH));
694 		lower = intel_uncore_read_fw(uncore, reg);
695 
696 		set(uncore, VLV_COUNTER_CONTROL,
697 		    _MASKED_BIT_ENABLE(VLV_COUNT_RANGE_HIGH));
698 		upper = intel_uncore_read_fw(uncore, reg);
699 	} while (upper != tmp && --loop);
700 
701 	/*
702 	 * Everywhere else we always use VLV_COUNTER_CONTROL with the
703 	 * VLV_COUNT_RANGE_HIGH bit set - so it is safe to leave it set
704 	 * now.
705 	 */
706 
707 	return lower | (u64)upper << 8;
708 }
709 
710 u64 intel_rc6_residency_ns(struct intel_rc6 *rc6, const i915_reg_t reg)
711 {
712 	struct drm_i915_private *i915 = rc6_to_i915(rc6);
713 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
714 	u64 time_hw, prev_hw, overflow_hw;
715 	unsigned int fw_domains;
716 	unsigned long flags;
717 	unsigned int i;
718 	u32 mul, div;
719 
720 	if (!rc6->supported)
721 		return 0;
722 
723 	/*
724 	 * Store previous hw counter values for counter wrap-around handling.
725 	 *
726 	 * There are only four interesting registers and they live next to each
727 	 * other so we can use the relative address, compared to the smallest
728 	 * one as the index into driver storage.
729 	 */
730 	i = (i915_mmio_reg_offset(reg) -
731 	     i915_mmio_reg_offset(GEN6_GT_GFX_RC6_LOCKED)) / sizeof(u32);
732 	if (drm_WARN_ON_ONCE(&i915->drm, i >= ARRAY_SIZE(rc6->cur_residency)))
733 		return 0;
734 
735 	fw_domains = intel_uncore_forcewake_for_reg(uncore, reg, FW_REG_READ);
736 
737 	spin_lock_irqsave(&uncore->lock, flags);
738 	intel_uncore_forcewake_get__locked(uncore, fw_domains);
739 
740 	/* On VLV and CHV, residency time is in CZ units rather than 1.28us */
741 	if (IS_VALLEYVIEW(i915) || IS_CHERRYVIEW(i915)) {
742 		mul = 1000000;
743 		div = i915->czclk_freq;
744 		overflow_hw = BIT_ULL(40);
745 		time_hw = vlv_residency_raw(uncore, reg);
746 	} else {
747 		/* 833.33ns units on Gen9LP, 1.28us elsewhere. */
748 		if (IS_GEN9_LP(i915)) {
749 			mul = 10000;
750 			div = 12;
751 		} else {
752 			mul = 1280;
753 			div = 1;
754 		}
755 
756 		overflow_hw = BIT_ULL(32);
757 		time_hw = intel_uncore_read_fw(uncore, reg);
758 	}
759 
760 	/*
761 	 * Counter wrap handling.
762 	 *
763 	 * But relying on a sufficient frequency of queries otherwise counters
764 	 * can still wrap.
765 	 */
766 	prev_hw = rc6->prev_hw_residency[i];
767 	rc6->prev_hw_residency[i] = time_hw;
768 
769 	/* RC6 delta from last sample. */
770 	if (time_hw >= prev_hw)
771 		time_hw -= prev_hw;
772 	else
773 		time_hw += overflow_hw - prev_hw;
774 
775 	/* Add delta to RC6 extended raw driver copy. */
776 	time_hw += rc6->cur_residency[i];
777 	rc6->cur_residency[i] = time_hw;
778 
779 	intel_uncore_forcewake_put__locked(uncore, fw_domains);
780 	spin_unlock_irqrestore(&uncore->lock, flags);
781 
782 	return mul_u64_u32_div(time_hw, mul, div);
783 }
784 
785 u64 intel_rc6_residency_us(struct intel_rc6 *rc6, i915_reg_t reg)
786 {
787 	return DIV_ROUND_UP_ULL(intel_rc6_residency_ns(rc6, reg), 1000);
788 }
789 
790 #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
791 #include "selftest_rc6.c"
792 #endif
793