xref: /openbmc/linux/drivers/gpu/drm/i915/gt/intel_rc6.c (revision 2bad466c)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2019 Intel Corporation
4  */
5 
6 #include <linux/pm_runtime.h>
7 #include <linux/string_helpers.h>
8 
9 #include "gem/i915_gem_region.h"
10 #include "i915_drv.h"
11 #include "i915_reg.h"
12 #include "i915_vgpu.h"
13 #include "intel_engine_regs.h"
14 #include "intel_gt.h"
15 #include "intel_gt_pm.h"
16 #include "intel_gt_regs.h"
17 #include "intel_pcode.h"
18 #include "intel_rc6.h"
19 
20 /**
21  * DOC: RC6
22  *
23  * RC6 is a special power stage which allows the GPU to enter an very
24  * low-voltage mode when idle, using down to 0V while at this stage.  This
25  * stage is entered automatically when the GPU is idle when RC6 support is
26  * enabled, and as soon as new workload arises GPU wakes up automatically as
27  * well.
28  *
29  * There are different RC6 modes available in Intel GPU, which differentiate
30  * among each other with the latency required to enter and leave RC6 and
31  * voltage consumed by the GPU in different states.
32  *
33  * The combination of the following flags define which states GPU is allowed
34  * to enter, while RC6 is the normal RC6 state, RC6p is the deep RC6, and
35  * RC6pp is deepest RC6. Their support by hardware varies according to the
36  * GPU, BIOS, chipset and platform. RC6 is usually the safest one and the one
37  * which brings the most power savings; deeper states save more power, but
38  * require higher latency to switch to and wake up.
39  */
40 
41 static struct intel_gt *rc6_to_gt(struct intel_rc6 *rc6)
42 {
43 	return container_of(rc6, struct intel_gt, rc6);
44 }
45 
46 static struct intel_uncore *rc6_to_uncore(struct intel_rc6 *rc)
47 {
48 	return rc6_to_gt(rc)->uncore;
49 }
50 
51 static struct drm_i915_private *rc6_to_i915(struct intel_rc6 *rc)
52 {
53 	return rc6_to_gt(rc)->i915;
54 }
55 
56 static void set(struct intel_uncore *uncore, i915_reg_t reg, u32 val)
57 {
58 	intel_uncore_write_fw(uncore, reg, val);
59 }
60 
61 static void gen11_rc6_enable(struct intel_rc6 *rc6)
62 {
63 	struct intel_gt *gt = rc6_to_gt(rc6);
64 	struct intel_uncore *uncore = gt->uncore;
65 	struct intel_engine_cs *engine;
66 	enum intel_engine_id id;
67 	u32 pg_enable;
68 	int i;
69 
70 	/*
71 	 * With GuCRC, these parameters are set by GuC
72 	 */
73 	if (!intel_uc_uses_guc_rc(&gt->uc)) {
74 		/* 2b: Program RC6 thresholds.*/
75 		set(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 54 << 16 | 85);
76 		set(uncore, GEN10_MEDIA_WAKE_RATE_LIMIT, 150);
77 
78 		set(uncore, GEN6_RC_EVALUATION_INTERVAL, 125000); /* 12500 * 1280ns */
79 		set(uncore, GEN6_RC_IDLE_HYSTERSIS, 25); /* 25 * 1280ns */
80 		for_each_engine(engine, rc6_to_gt(rc6), id)
81 			set(uncore, RING_MAX_IDLE(engine->mmio_base), 10);
82 
83 		set(uncore, GUC_MAX_IDLE_COUNT, 0xA);
84 
85 		set(uncore, GEN6_RC_SLEEP, 0);
86 
87 		set(uncore, GEN6_RC6_THRESHOLD, 50000); /* 50/125ms per EI */
88 	}
89 
90 	/*
91 	 * 2c: Program Coarse Power Gating Policies.
92 	 *
93 	 * Bspec's guidance is to use 25us (really 25 * 1280ns) here. What we
94 	 * use instead is a more conservative estimate for the maximum time
95 	 * it takes us to service a CS interrupt and submit a new ELSP - that
96 	 * is the time which the GPU is idle waiting for the CPU to select the
97 	 * next request to execute. If the idle hysteresis is less than that
98 	 * interrupt service latency, the hardware will automatically gate
99 	 * the power well and we will then incur the wake up cost on top of
100 	 * the service latency. A similar guide from plane_state is that we
101 	 * do not want the enable hysteresis to less than the wakeup latency.
102 	 *
103 	 * igt/gem_exec_nop/sequential provides a rough estimate for the
104 	 * service latency, and puts it under 10us for Icelake, similar to
105 	 * Broadwell+, To be conservative, we want to factor in a context
106 	 * switch on top (due to ksoftirqd).
107 	 */
108 	set(uncore, GEN9_MEDIA_PG_IDLE_HYSTERESIS, 60);
109 	set(uncore, GEN9_RENDER_PG_IDLE_HYSTERESIS, 60);
110 
111 	/* 3a: Enable RC6
112 	 *
113 	 * With GuCRC, we do not enable bit 31 of RC_CTL,
114 	 * thus allowing GuC to control RC6 entry/exit fully instead.
115 	 * We will not set the HW ENABLE and EI bits
116 	 */
117 	if (!intel_guc_rc_enable(&gt->uc.guc))
118 		rc6->ctl_enable = GEN6_RC_CTL_RC6_ENABLE;
119 	else
120 		rc6->ctl_enable =
121 			GEN6_RC_CTL_HW_ENABLE |
122 			GEN6_RC_CTL_RC6_ENABLE |
123 			GEN6_RC_CTL_EI_MODE(1);
124 
125 	/* Wa_16011777198 - Render powergating must remain disabled */
126 	if (IS_DG2_GRAPHICS_STEP(gt->i915, G10, STEP_A0, STEP_C0) ||
127 	    IS_DG2_GRAPHICS_STEP(gt->i915, G11, STEP_A0, STEP_B0))
128 		pg_enable =
129 			GEN9_MEDIA_PG_ENABLE |
130 			GEN11_MEDIA_SAMPLER_PG_ENABLE;
131 	else
132 		pg_enable =
133 			GEN9_RENDER_PG_ENABLE |
134 			GEN9_MEDIA_PG_ENABLE |
135 			GEN11_MEDIA_SAMPLER_PG_ENABLE;
136 
137 	if (GRAPHICS_VER(gt->i915) >= 12) {
138 		for (i = 0; i < I915_MAX_VCS; i++)
139 			if (HAS_ENGINE(gt, _VCS(i)))
140 				pg_enable |= (VDN_HCP_POWERGATE_ENABLE(i) |
141 					      VDN_MFX_POWERGATE_ENABLE(i));
142 	}
143 
144 	set(uncore, GEN9_PG_ENABLE, pg_enable);
145 }
146 
147 static void gen9_rc6_enable(struct intel_rc6 *rc6)
148 {
149 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
150 	struct intel_engine_cs *engine;
151 	enum intel_engine_id id;
152 
153 	/* 2b: Program RC6 thresholds.*/
154 	if (GRAPHICS_VER(rc6_to_i915(rc6)) >= 11) {
155 		set(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 54 << 16 | 85);
156 		set(uncore, GEN10_MEDIA_WAKE_RATE_LIMIT, 150);
157 	} else if (IS_SKYLAKE(rc6_to_i915(rc6))) {
158 		/*
159 		 * WaRsDoubleRc6WrlWithCoarsePowerGating:skl Doubling WRL only
160 		 * when CPG is enabled
161 		 */
162 		set(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 108 << 16);
163 	} else {
164 		set(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 54 << 16);
165 	}
166 
167 	set(uncore, GEN6_RC_EVALUATION_INTERVAL, 125000); /* 12500 * 1280ns */
168 	set(uncore, GEN6_RC_IDLE_HYSTERSIS, 25); /* 25 * 1280ns */
169 	for_each_engine(engine, rc6_to_gt(rc6), id)
170 		set(uncore, RING_MAX_IDLE(engine->mmio_base), 10);
171 
172 	set(uncore, GUC_MAX_IDLE_COUNT, 0xA);
173 
174 	set(uncore, GEN6_RC_SLEEP, 0);
175 
176 	/*
177 	 * 2c: Program Coarse Power Gating Policies.
178 	 *
179 	 * Bspec's guidance is to use 25us (really 25 * 1280ns) here. What we
180 	 * use instead is a more conservative estimate for the maximum time
181 	 * it takes us to service a CS interrupt and submit a new ELSP - that
182 	 * is the time which the GPU is idle waiting for the CPU to select the
183 	 * next request to execute. If the idle hysteresis is less than that
184 	 * interrupt service latency, the hardware will automatically gate
185 	 * the power well and we will then incur the wake up cost on top of
186 	 * the service latency. A similar guide from plane_state is that we
187 	 * do not want the enable hysteresis to less than the wakeup latency.
188 	 *
189 	 * igt/gem_exec_nop/sequential provides a rough estimate for the
190 	 * service latency, and puts it around 10us for Broadwell (and other
191 	 * big core) and around 40us for Broxton (and other low power cores).
192 	 * [Note that for legacy ringbuffer submission, this is less than 1us!]
193 	 * However, the wakeup latency on Broxton is closer to 100us. To be
194 	 * conservative, we have to factor in a context switch on top (due
195 	 * to ksoftirqd).
196 	 */
197 	set(uncore, GEN9_MEDIA_PG_IDLE_HYSTERESIS, 250);
198 	set(uncore, GEN9_RENDER_PG_IDLE_HYSTERESIS, 250);
199 
200 	/* 3a: Enable RC6 */
201 	set(uncore, GEN6_RC6_THRESHOLD, 37500); /* 37.5/125ms per EI */
202 
203 	rc6->ctl_enable =
204 		GEN6_RC_CTL_HW_ENABLE |
205 		GEN6_RC_CTL_RC6_ENABLE |
206 		GEN6_RC_CTL_EI_MODE(1);
207 
208 	/*
209 	 * WaRsDisableCoarsePowerGating:skl,cnl
210 	 *   - Render/Media PG need to be disabled with RC6.
211 	 */
212 	if (!NEEDS_WaRsDisableCoarsePowerGating(rc6_to_i915(rc6)))
213 		set(uncore, GEN9_PG_ENABLE,
214 		    GEN9_RENDER_PG_ENABLE | GEN9_MEDIA_PG_ENABLE);
215 }
216 
217 static void gen8_rc6_enable(struct intel_rc6 *rc6)
218 {
219 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
220 	struct intel_engine_cs *engine;
221 	enum intel_engine_id id;
222 
223 	/* 2b: Program RC6 thresholds.*/
224 	set(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 40 << 16);
225 	set(uncore, GEN6_RC_EVALUATION_INTERVAL, 125000); /* 12500 * 1280ns */
226 	set(uncore, GEN6_RC_IDLE_HYSTERSIS, 25); /* 25 * 1280ns */
227 	for_each_engine(engine, rc6_to_gt(rc6), id)
228 		set(uncore, RING_MAX_IDLE(engine->mmio_base), 10);
229 	set(uncore, GEN6_RC_SLEEP, 0);
230 	set(uncore, GEN6_RC6_THRESHOLD, 625); /* 800us/1.28 for TO */
231 
232 	/* 3: Enable RC6 */
233 	rc6->ctl_enable =
234 	    GEN6_RC_CTL_HW_ENABLE |
235 	    GEN7_RC_CTL_TO_MODE |
236 	    GEN6_RC_CTL_RC6_ENABLE;
237 }
238 
239 static void gen6_rc6_enable(struct intel_rc6 *rc6)
240 {
241 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
242 	struct drm_i915_private *i915 = rc6_to_i915(rc6);
243 	struct intel_engine_cs *engine;
244 	enum intel_engine_id id;
245 	u32 rc6vids, rc6_mask;
246 	int ret;
247 
248 	set(uncore, GEN6_RC1_WAKE_RATE_LIMIT, 1000 << 16);
249 	set(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 40 << 16 | 30);
250 	set(uncore, GEN6_RC6pp_WAKE_RATE_LIMIT, 30);
251 	set(uncore, GEN6_RC_EVALUATION_INTERVAL, 125000);
252 	set(uncore, GEN6_RC_IDLE_HYSTERSIS, 25);
253 
254 	for_each_engine(engine, rc6_to_gt(rc6), id)
255 		set(uncore, RING_MAX_IDLE(engine->mmio_base), 10);
256 
257 	set(uncore, GEN6_RC_SLEEP, 0);
258 	set(uncore, GEN6_RC1e_THRESHOLD, 1000);
259 	set(uncore, GEN6_RC6_THRESHOLD, 50000);
260 	set(uncore, GEN6_RC6p_THRESHOLD, 150000);
261 	set(uncore, GEN6_RC6pp_THRESHOLD, 64000); /* unused */
262 
263 	/* We don't use those on Haswell */
264 	rc6_mask = GEN6_RC_CTL_RC6_ENABLE;
265 	if (HAS_RC6p(i915))
266 		rc6_mask |= GEN6_RC_CTL_RC6p_ENABLE;
267 	if (HAS_RC6pp(i915))
268 		rc6_mask |= GEN6_RC_CTL_RC6pp_ENABLE;
269 	rc6->ctl_enable =
270 	    rc6_mask |
271 	    GEN6_RC_CTL_EI_MODE(1) |
272 	    GEN6_RC_CTL_HW_ENABLE;
273 
274 	rc6vids = 0;
275 	ret = snb_pcode_read(rc6_to_gt(rc6)->uncore, GEN6_PCODE_READ_RC6VIDS, &rc6vids, NULL);
276 	if (GRAPHICS_VER(i915) == 6 && ret) {
277 		drm_dbg(&i915->drm, "Couldn't check for BIOS workaround\n");
278 	} else if (GRAPHICS_VER(i915) == 6 &&
279 		   (GEN6_DECODE_RC6_VID(rc6vids & 0xff) < 450)) {
280 		drm_dbg(&i915->drm,
281 			"You should update your BIOS. Correcting minimum rc6 voltage (%dmV->%dmV)\n",
282 			GEN6_DECODE_RC6_VID(rc6vids & 0xff), 450);
283 		rc6vids &= 0xffff00;
284 		rc6vids |= GEN6_ENCODE_RC6_VID(450);
285 		ret = snb_pcode_write(rc6_to_gt(rc6)->uncore, GEN6_PCODE_WRITE_RC6VIDS, rc6vids);
286 		if (ret)
287 			drm_err(&i915->drm,
288 				"Couldn't fix incorrect rc6 voltage\n");
289 	}
290 }
291 
292 /* Check that the pcbr address is not empty. */
293 static int chv_rc6_init(struct intel_rc6 *rc6)
294 {
295 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
296 	struct drm_i915_private *i915 = rc6_to_i915(rc6);
297 	resource_size_t pctx_paddr, paddr;
298 	resource_size_t pctx_size = 32 * SZ_1K;
299 	u32 pcbr;
300 
301 	pcbr = intel_uncore_read(uncore, VLV_PCBR);
302 	if ((pcbr >> VLV_PCBR_ADDR_SHIFT) == 0) {
303 		drm_dbg(&i915->drm, "BIOS didn't set up PCBR, fixing up\n");
304 		paddr = i915->dsm.stolen.end + 1 - pctx_size;
305 		GEM_BUG_ON(paddr > U32_MAX);
306 
307 		pctx_paddr = (paddr & ~4095);
308 		intel_uncore_write(uncore, VLV_PCBR, pctx_paddr);
309 	}
310 
311 	return 0;
312 }
313 
314 static int vlv_rc6_init(struct intel_rc6 *rc6)
315 {
316 	struct drm_i915_private *i915 = rc6_to_i915(rc6);
317 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
318 	struct drm_i915_gem_object *pctx;
319 	resource_size_t pctx_paddr;
320 	resource_size_t pctx_size = 24 * SZ_1K;
321 	u32 pcbr;
322 
323 	pcbr = intel_uncore_read(uncore, VLV_PCBR);
324 	if (pcbr) {
325 		/* BIOS set it up already, grab the pre-alloc'd space */
326 		resource_size_t pcbr_offset;
327 
328 		pcbr_offset = (pcbr & ~4095) - i915->dsm.stolen.start;
329 		pctx = i915_gem_object_create_region_at(i915->mm.stolen_region,
330 							pcbr_offset,
331 							pctx_size,
332 							0);
333 		if (IS_ERR(pctx))
334 			return PTR_ERR(pctx);
335 
336 		goto out;
337 	}
338 
339 	drm_dbg(&i915->drm, "BIOS didn't set up PCBR, fixing up\n");
340 
341 	/*
342 	 * From the Gunit register HAS:
343 	 * The Gfx driver is expected to program this register and ensure
344 	 * proper allocation within Gfx stolen memory.  For example, this
345 	 * register should be programmed such than the PCBR range does not
346 	 * overlap with other ranges, such as the frame buffer, protected
347 	 * memory, or any other relevant ranges.
348 	 */
349 	pctx = i915_gem_object_create_stolen(i915, pctx_size);
350 	if (IS_ERR(pctx)) {
351 		drm_dbg(&i915->drm,
352 			"not enough stolen space for PCTX, disabling\n");
353 		return PTR_ERR(pctx);
354 	}
355 
356 	GEM_BUG_ON(range_overflows_end_t(u64,
357 					 i915->dsm.stolen.start,
358 					 pctx->stolen->start,
359 					 U32_MAX));
360 	pctx_paddr = i915->dsm.stolen.start + pctx->stolen->start;
361 	intel_uncore_write(uncore, VLV_PCBR, pctx_paddr);
362 
363 out:
364 	rc6->pctx = pctx;
365 	return 0;
366 }
367 
368 static void chv_rc6_enable(struct intel_rc6 *rc6)
369 {
370 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
371 	struct intel_engine_cs *engine;
372 	enum intel_engine_id id;
373 
374 	/* 2a: Program RC6 thresholds.*/
375 	set(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 40 << 16);
376 	set(uncore, GEN6_RC_EVALUATION_INTERVAL, 125000); /* 12500 * 1280ns */
377 	set(uncore, GEN6_RC_IDLE_HYSTERSIS, 25); /* 25 * 1280ns */
378 
379 	for_each_engine(engine, rc6_to_gt(rc6), id)
380 		set(uncore, RING_MAX_IDLE(engine->mmio_base), 10);
381 	set(uncore, GEN6_RC_SLEEP, 0);
382 
383 	/* TO threshold set to 500 us (0x186 * 1.28 us) */
384 	set(uncore, GEN6_RC6_THRESHOLD, 0x186);
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_RC6_COUNT_EN |
390 			       VLV_RENDER_RC6_COUNT_EN));
391 
392 	/* 3: Enable RC6 */
393 	rc6->ctl_enable = GEN7_RC_CTL_TO_MODE;
394 }
395 
396 static void vlv_rc6_enable(struct intel_rc6 *rc6)
397 {
398 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
399 	struct intel_engine_cs *engine;
400 	enum intel_engine_id id;
401 
402 	set(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 0x00280000);
403 	set(uncore, GEN6_RC_EVALUATION_INTERVAL, 125000);
404 	set(uncore, GEN6_RC_IDLE_HYSTERSIS, 25);
405 
406 	for_each_engine(engine, rc6_to_gt(rc6), id)
407 		set(uncore, RING_MAX_IDLE(engine->mmio_base), 10);
408 
409 	set(uncore, GEN6_RC6_THRESHOLD, 0x557);
410 
411 	/* Allows RC6 residency counter to work */
412 	set(uncore, VLV_COUNTER_CONTROL,
413 	    _MASKED_BIT_ENABLE(VLV_COUNT_RANGE_HIGH |
414 			       VLV_MEDIA_RC0_COUNT_EN |
415 			       VLV_RENDER_RC0_COUNT_EN |
416 			       VLV_MEDIA_RC6_COUNT_EN |
417 			       VLV_RENDER_RC6_COUNT_EN));
418 
419 	rc6->ctl_enable =
420 	    GEN7_RC_CTL_TO_MODE | VLV_RC_CTL_CTX_RST_PARALLEL;
421 }
422 
423 static bool bxt_check_bios_rc6_setup(struct intel_rc6 *rc6)
424 {
425 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
426 	struct drm_i915_private *i915 = rc6_to_i915(rc6);
427 	u32 rc6_ctx_base, rc_ctl, rc_sw_target;
428 	bool enable_rc6 = true;
429 
430 	rc_ctl = intel_uncore_read(uncore, GEN6_RC_CONTROL);
431 	rc_sw_target = intel_uncore_read(uncore, GEN6_RC_STATE);
432 	rc_sw_target &= RC_SW_TARGET_STATE_MASK;
433 	rc_sw_target >>= RC_SW_TARGET_STATE_SHIFT;
434 	drm_dbg(&i915->drm, "BIOS enabled RC states: "
435 			 "HW_CTRL %s HW_RC6 %s SW_TARGET_STATE %x\n",
436 			 str_on_off(rc_ctl & GEN6_RC_CTL_HW_ENABLE),
437 			 str_on_off(rc_ctl & GEN6_RC_CTL_RC6_ENABLE),
438 			 rc_sw_target);
439 
440 	if (!(intel_uncore_read(uncore, RC6_LOCATION) & RC6_CTX_IN_DRAM)) {
441 		drm_dbg(&i915->drm, "RC6 Base location not set properly.\n");
442 		enable_rc6 = false;
443 	}
444 
445 	/*
446 	 * The exact context size is not known for BXT, so assume a page size
447 	 * for this check.
448 	 */
449 	rc6_ctx_base =
450 		intel_uncore_read(uncore, RC6_CTX_BASE) & RC6_CTX_BASE_MASK;
451 	if (!(rc6_ctx_base >= i915->dsm.reserved.start &&
452 	      rc6_ctx_base + PAGE_SIZE < i915->dsm.reserved.end)) {
453 		drm_dbg(&i915->drm, "RC6 Base address not as expected.\n");
454 		enable_rc6 = false;
455 	}
456 
457 	if (!((intel_uncore_read(uncore, PWRCTX_MAXCNT(RENDER_RING_BASE)) & IDLE_TIME_MASK) > 1 &&
458 	      (intel_uncore_read(uncore, PWRCTX_MAXCNT(GEN6_BSD_RING_BASE)) & IDLE_TIME_MASK) > 1 &&
459 	      (intel_uncore_read(uncore, PWRCTX_MAXCNT(BLT_RING_BASE)) & IDLE_TIME_MASK) > 1 &&
460 	      (intel_uncore_read(uncore, PWRCTX_MAXCNT(VEBOX_RING_BASE)) & IDLE_TIME_MASK) > 1)) {
461 		drm_dbg(&i915->drm,
462 			"Engine Idle wait time not set properly.\n");
463 		enable_rc6 = false;
464 	}
465 
466 	if (!intel_uncore_read(uncore, GEN8_PUSHBUS_CONTROL) ||
467 	    !intel_uncore_read(uncore, GEN8_PUSHBUS_ENABLE) ||
468 	    !intel_uncore_read(uncore, GEN8_PUSHBUS_SHIFT)) {
469 		drm_dbg(&i915->drm, "Pushbus not setup properly.\n");
470 		enable_rc6 = false;
471 	}
472 
473 	if (!intel_uncore_read(uncore, GEN6_GFXPAUSE)) {
474 		drm_dbg(&i915->drm, "GFX pause not setup properly.\n");
475 		enable_rc6 = false;
476 	}
477 
478 	if (!intel_uncore_read(uncore, GEN8_MISC_CTRL0)) {
479 		drm_dbg(&i915->drm, "GPM control not setup properly.\n");
480 		enable_rc6 = false;
481 	}
482 
483 	return enable_rc6;
484 }
485 
486 static bool rc6_supported(struct intel_rc6 *rc6)
487 {
488 	struct drm_i915_private *i915 = rc6_to_i915(rc6);
489 	struct intel_gt *gt = rc6_to_gt(rc6);
490 
491 	if (!HAS_RC6(i915))
492 		return false;
493 
494 	if (intel_vgpu_active(i915))
495 		return false;
496 
497 	if (is_mock_gt(rc6_to_gt(rc6)))
498 		return false;
499 
500 	if (IS_GEN9_LP(i915) && !bxt_check_bios_rc6_setup(rc6)) {
501 		drm_notice(&i915->drm,
502 			   "RC6 and powersaving disabled by BIOS\n");
503 		return false;
504 	}
505 
506 	if (IS_MTL_MEDIA_STEP(gt->i915, STEP_A0, STEP_B0) &&
507 	    gt->type == GT_MEDIA) {
508 		drm_notice(&i915->drm,
509 			   "Media RC6 disabled on A step\n");
510 		return false;
511 	}
512 
513 	return true;
514 }
515 
516 static void rpm_get(struct intel_rc6 *rc6)
517 {
518 	GEM_BUG_ON(rc6->wakeref);
519 	pm_runtime_get_sync(rc6_to_i915(rc6)->drm.dev);
520 	rc6->wakeref = true;
521 }
522 
523 static void rpm_put(struct intel_rc6 *rc6)
524 {
525 	GEM_BUG_ON(!rc6->wakeref);
526 	pm_runtime_put(rc6_to_i915(rc6)->drm.dev);
527 	rc6->wakeref = false;
528 }
529 
530 static bool pctx_corrupted(struct intel_rc6 *rc6)
531 {
532 	struct drm_i915_private *i915 = rc6_to_i915(rc6);
533 
534 	if (!NEEDS_RC6_CTX_CORRUPTION_WA(i915))
535 		return false;
536 
537 	if (intel_uncore_read(rc6_to_uncore(rc6), GEN8_RC6_CTX_INFO))
538 		return false;
539 
540 	drm_notice(&i915->drm,
541 		   "RC6 context corruption, disabling runtime power management\n");
542 	return true;
543 }
544 
545 static void __intel_rc6_disable(struct intel_rc6 *rc6)
546 {
547 	struct drm_i915_private *i915 = rc6_to_i915(rc6);
548 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
549 	struct intel_gt *gt = rc6_to_gt(rc6);
550 
551 	/* Take control of RC6 back from GuC */
552 	intel_guc_rc_disable(&gt->uc.guc);
553 
554 	intel_uncore_forcewake_get(uncore, FORCEWAKE_ALL);
555 	if (GRAPHICS_VER(i915) >= 9)
556 		set(uncore, GEN9_PG_ENABLE, 0);
557 	set(uncore, GEN6_RC_CONTROL, 0);
558 	set(uncore, GEN6_RC_STATE, 0);
559 	intel_uncore_forcewake_put(uncore, FORCEWAKE_ALL);
560 }
561 
562 static void rc6_res_reg_init(struct intel_rc6 *rc6)
563 {
564 	memset(rc6->res_reg, INVALID_MMIO_REG.reg, sizeof(rc6->res_reg));
565 
566 	switch (rc6_to_gt(rc6)->type) {
567 	case GT_MEDIA:
568 		rc6->res_reg[INTEL_RC6_RES_RC6] = MTL_MEDIA_MC6;
569 		break;
570 	default:
571 		rc6->res_reg[INTEL_RC6_RES_RC6_LOCKED] = GEN6_GT_GFX_RC6_LOCKED;
572 		rc6->res_reg[INTEL_RC6_RES_RC6] = GEN6_GT_GFX_RC6;
573 		rc6->res_reg[INTEL_RC6_RES_RC6p] = GEN6_GT_GFX_RC6p;
574 		rc6->res_reg[INTEL_RC6_RES_RC6pp] = GEN6_GT_GFX_RC6pp;
575 		break;
576 	}
577 }
578 
579 void intel_rc6_init(struct intel_rc6 *rc6)
580 {
581 	struct drm_i915_private *i915 = rc6_to_i915(rc6);
582 	int err;
583 
584 	/* Disable runtime-pm until we can save the GPU state with rc6 pctx */
585 	rpm_get(rc6);
586 
587 	if (!rc6_supported(rc6))
588 		return;
589 
590 	rc6_res_reg_init(rc6);
591 
592 	if (IS_CHERRYVIEW(i915))
593 		err = chv_rc6_init(rc6);
594 	else if (IS_VALLEYVIEW(i915))
595 		err = vlv_rc6_init(rc6);
596 	else
597 		err = 0;
598 
599 	/* Sanitize rc6, ensure it is disabled before we are ready. */
600 	__intel_rc6_disable(rc6);
601 
602 	rc6->supported = err == 0;
603 }
604 
605 void intel_rc6_sanitize(struct intel_rc6 *rc6)
606 {
607 	memset(rc6->prev_hw_residency, 0, sizeof(rc6->prev_hw_residency));
608 
609 	if (rc6->enabled) { /* unbalanced suspend/resume */
610 		rpm_get(rc6);
611 		rc6->enabled = false;
612 	}
613 
614 	if (rc6->supported)
615 		__intel_rc6_disable(rc6);
616 }
617 
618 void intel_rc6_enable(struct intel_rc6 *rc6)
619 {
620 	struct drm_i915_private *i915 = rc6_to_i915(rc6);
621 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
622 
623 	if (!rc6->supported)
624 		return;
625 
626 	GEM_BUG_ON(rc6->enabled);
627 
628 	intel_uncore_forcewake_get(uncore, FORCEWAKE_ALL);
629 
630 	if (IS_CHERRYVIEW(i915))
631 		chv_rc6_enable(rc6);
632 	else if (IS_VALLEYVIEW(i915))
633 		vlv_rc6_enable(rc6);
634 	else if (GRAPHICS_VER(i915) >= 11)
635 		gen11_rc6_enable(rc6);
636 	else if (GRAPHICS_VER(i915) >= 9)
637 		gen9_rc6_enable(rc6);
638 	else if (IS_BROADWELL(i915))
639 		gen8_rc6_enable(rc6);
640 	else if (GRAPHICS_VER(i915) >= 6)
641 		gen6_rc6_enable(rc6);
642 
643 	rc6->manual = rc6->ctl_enable & GEN6_RC_CTL_RC6_ENABLE;
644 	if (NEEDS_RC6_CTX_CORRUPTION_WA(i915))
645 		rc6->ctl_enable = 0;
646 
647 	intel_uncore_forcewake_put(uncore, FORCEWAKE_ALL);
648 
649 	if (unlikely(pctx_corrupted(rc6)))
650 		return;
651 
652 	/* rc6 is ready, runtime-pm is go! */
653 	rpm_put(rc6);
654 	rc6->enabled = true;
655 }
656 
657 void intel_rc6_unpark(struct intel_rc6 *rc6)
658 {
659 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
660 
661 	if (!rc6->enabled)
662 		return;
663 
664 	/* Restore HW timers for automatic RC6 entry while busy */
665 	set(uncore, GEN6_RC_CONTROL, rc6->ctl_enable);
666 }
667 
668 void intel_rc6_park(struct intel_rc6 *rc6)
669 {
670 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
671 	unsigned int target;
672 
673 	if (!rc6->enabled)
674 		return;
675 
676 	if (unlikely(pctx_corrupted(rc6))) {
677 		intel_rc6_disable(rc6);
678 		return;
679 	}
680 
681 	if (!rc6->manual)
682 		return;
683 
684 	/* Turn off the HW timers and go directly to rc6 */
685 	set(uncore, GEN6_RC_CONTROL, GEN6_RC_CTL_RC6_ENABLE);
686 
687 	if (HAS_RC6pp(rc6_to_i915(rc6)))
688 		target = 0x6; /* deepest rc6 */
689 	else if (HAS_RC6p(rc6_to_i915(rc6)))
690 		target = 0x5; /* deep rc6 */
691 	else
692 		target = 0x4; /* normal rc6 */
693 	set(uncore, GEN6_RC_STATE, target << RC_SW_TARGET_STATE_SHIFT);
694 }
695 
696 void intel_rc6_disable(struct intel_rc6 *rc6)
697 {
698 	if (!rc6->enabled)
699 		return;
700 
701 	rpm_get(rc6);
702 	rc6->enabled = false;
703 
704 	__intel_rc6_disable(rc6);
705 }
706 
707 void intel_rc6_fini(struct intel_rc6 *rc6)
708 {
709 	struct drm_i915_gem_object *pctx;
710 
711 	intel_rc6_disable(rc6);
712 
713 	pctx = fetch_and_zero(&rc6->pctx);
714 	if (pctx)
715 		i915_gem_object_put(pctx);
716 
717 	if (rc6->wakeref)
718 		rpm_put(rc6);
719 }
720 
721 static u64 vlv_residency_raw(struct intel_uncore *uncore, const i915_reg_t reg)
722 {
723 	u32 lower, upper, tmp;
724 	int loop = 2;
725 
726 	/*
727 	 * The register accessed do not need forcewake. We borrow
728 	 * uncore lock to prevent concurrent access to range reg.
729 	 */
730 	lockdep_assert_held(&uncore->lock);
731 
732 	/*
733 	 * vlv and chv residency counters are 40 bits in width.
734 	 * With a control bit, we can choose between upper or lower
735 	 * 32bit window into this counter.
736 	 *
737 	 * Although we always use the counter in high-range mode elsewhere,
738 	 * userspace may attempt to read the value before rc6 is initialised,
739 	 * before we have set the default VLV_COUNTER_CONTROL value. So always
740 	 * set the high bit to be safe.
741 	 */
742 	set(uncore, VLV_COUNTER_CONTROL,
743 	    _MASKED_BIT_ENABLE(VLV_COUNT_RANGE_HIGH));
744 	upper = intel_uncore_read_fw(uncore, reg);
745 	do {
746 		tmp = upper;
747 
748 		set(uncore, VLV_COUNTER_CONTROL,
749 		    _MASKED_BIT_DISABLE(VLV_COUNT_RANGE_HIGH));
750 		lower = intel_uncore_read_fw(uncore, reg);
751 
752 		set(uncore, VLV_COUNTER_CONTROL,
753 		    _MASKED_BIT_ENABLE(VLV_COUNT_RANGE_HIGH));
754 		upper = intel_uncore_read_fw(uncore, reg);
755 	} while (upper != tmp && --loop);
756 
757 	/*
758 	 * Everywhere else we always use VLV_COUNTER_CONTROL with the
759 	 * VLV_COUNT_RANGE_HIGH bit set - so it is safe to leave it set
760 	 * now.
761 	 */
762 
763 	return lower | (u64)upper << 8;
764 }
765 
766 u64 intel_rc6_residency_ns(struct intel_rc6 *rc6, enum intel_rc6_res_type id)
767 {
768 	struct drm_i915_private *i915 = rc6_to_i915(rc6);
769 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
770 	u64 time_hw, prev_hw, overflow_hw;
771 	i915_reg_t reg = rc6->res_reg[id];
772 	unsigned int fw_domains;
773 	unsigned long flags;
774 	u32 mul, div;
775 
776 	if (!rc6->supported)
777 		return 0;
778 
779 	fw_domains = intel_uncore_forcewake_for_reg(uncore, reg, FW_REG_READ);
780 
781 	spin_lock_irqsave(&uncore->lock, flags);
782 	intel_uncore_forcewake_get__locked(uncore, fw_domains);
783 
784 	/* On VLV and CHV, residency time is in CZ units rather than 1.28us */
785 	if (IS_VALLEYVIEW(i915) || IS_CHERRYVIEW(i915)) {
786 		mul = 1000000;
787 		div = i915->czclk_freq;
788 		overflow_hw = BIT_ULL(40);
789 		time_hw = vlv_residency_raw(uncore, reg);
790 	} else {
791 		/* 833.33ns units on Gen9LP, 1.28us elsewhere. */
792 		if (IS_GEN9_LP(i915)) {
793 			mul = 10000;
794 			div = 12;
795 		} else {
796 			mul = 1280;
797 			div = 1;
798 		}
799 
800 		overflow_hw = BIT_ULL(32);
801 		time_hw = intel_uncore_read_fw(uncore, reg);
802 	}
803 
804 	/*
805 	 * Counter wrap handling.
806 	 *
807 	 * Store previous hw counter values for counter wrap-around handling. But
808 	 * relying on a sufficient frequency of queries otherwise counters can still wrap.
809 	 */
810 	prev_hw = rc6->prev_hw_residency[id];
811 	rc6->prev_hw_residency[id] = time_hw;
812 
813 	/* RC6 delta from last sample. */
814 	if (time_hw >= prev_hw)
815 		time_hw -= prev_hw;
816 	else
817 		time_hw += overflow_hw - prev_hw;
818 
819 	/* Add delta to RC6 extended raw driver copy. */
820 	time_hw += rc6->cur_residency[id];
821 	rc6->cur_residency[id] = time_hw;
822 
823 	intel_uncore_forcewake_put__locked(uncore, fw_domains);
824 	spin_unlock_irqrestore(&uncore->lock, flags);
825 
826 	return mul_u64_u32_div(time_hw, mul, div);
827 }
828 
829 u64 intel_rc6_residency_us(struct intel_rc6 *rc6, enum intel_rc6_res_type id)
830 {
831 	return DIV_ROUND_UP_ULL(intel_rc6_residency_ns(rc6, id), 1000);
832 }
833 
834 void intel_rc6_print_residency(struct seq_file *m, const char *title,
835 			       enum intel_rc6_res_type id)
836 {
837 	struct intel_gt *gt = m->private;
838 	i915_reg_t reg = gt->rc6.res_reg[id];
839 	intel_wakeref_t wakeref;
840 
841 	with_intel_runtime_pm(gt->uncore->rpm, wakeref)
842 		seq_printf(m, "%s %u (%llu us)\n", title,
843 			   intel_uncore_read(gt->uncore, reg),
844 			   intel_rc6_residency_us(&gt->rc6, id));
845 }
846 
847 #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
848 #include "selftest_rc6.c"
849 #endif
850