xref: /openbmc/linux/drivers/gpu/drm/i915/gt/intel_rc6.c (revision d699090510c3223641a23834b4710e2d4309a6ad)
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 
rc6_to_gt(struct intel_rc6 * rc6)41 static struct intel_gt *rc6_to_gt(struct intel_rc6 *rc6)
42 {
43 	return container_of(rc6, struct intel_gt, rc6);
44 }
45 
rc6_to_uncore(struct intel_rc6 * rc)46 static struct intel_uncore *rc6_to_uncore(struct intel_rc6 *rc)
47 {
48 	return rc6_to_gt(rc)->uncore;
49 }
50 
rc6_to_i915(struct intel_rc6 * rc)51 static struct drm_i915_private *rc6_to_i915(struct intel_rc6 *rc)
52 {
53 	return rc6_to_gt(rc)->i915;
54 }
55 
gen11_rc6_enable(struct intel_rc6 * rc6)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 	/*
66 	 * With GuCRC, these parameters are set by GuC
67 	 */
68 	if (!intel_uc_uses_guc_rc(&gt->uc)) {
69 		/* 2b: Program RC6 thresholds.*/
70 		intel_uncore_write_fw(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 54 << 16 | 85);
71 		intel_uncore_write_fw(uncore, GEN10_MEDIA_WAKE_RATE_LIMIT, 150);
72 
73 		intel_uncore_write_fw(uncore, GEN6_RC_EVALUATION_INTERVAL, 125000); /* 12500 * 1280ns */
74 		intel_uncore_write_fw(uncore, GEN6_RC_IDLE_HYSTERSIS, 25); /* 25 * 1280ns */
75 		for_each_engine(engine, rc6_to_gt(rc6), id)
76 			intel_uncore_write_fw(uncore, RING_MAX_IDLE(engine->mmio_base), 10);
77 
78 		intel_uncore_write_fw(uncore, GUC_MAX_IDLE_COUNT, 0xA);
79 
80 		intel_uncore_write_fw(uncore, GEN6_RC_SLEEP, 0);
81 
82 		intel_uncore_write_fw(uncore, GEN6_RC6_THRESHOLD, 50000); /* 50/125ms per EI */
83 	}
84 
85 	/*
86 	 * 2c: Program Coarse Power Gating Policies.
87 	 *
88 	 * Bspec's guidance is to use 25us (really 25 * 1280ns) here. What we
89 	 * use instead is a more conservative estimate for the maximum time
90 	 * it takes us to service a CS interrupt and submit a new ELSP - that
91 	 * is the time which the GPU is idle waiting for the CPU to select the
92 	 * next request to execute. If the idle hysteresis is less than that
93 	 * interrupt service latency, the hardware will automatically gate
94 	 * the power well and we will then incur the wake up cost on top of
95 	 * the service latency. A similar guide from plane_state is that we
96 	 * do not want the enable hysteresis to less than the wakeup latency.
97 	 *
98 	 * igt/gem_exec_nop/sequential provides a rough estimate for the
99 	 * service latency, and puts it under 10us for Icelake, similar to
100 	 * Broadwell+, To be conservative, we want to factor in a context
101 	 * switch on top (due to ksoftirqd).
102 	 */
103 	intel_uncore_write_fw(uncore, GEN9_MEDIA_PG_IDLE_HYSTERESIS, 60);
104 	intel_uncore_write_fw(uncore, GEN9_RENDER_PG_IDLE_HYSTERESIS, 60);
105 
106 	/* 3a: Enable RC6
107 	 *
108 	 * With GuCRC, we do not enable bit 31 of RC_CTL,
109 	 * thus allowing GuC to control RC6 entry/exit fully instead.
110 	 * We will not set the HW ENABLE and EI bits
111 	 */
112 	if (!intel_guc_rc_enable(&gt->uc.guc))
113 		rc6->ctl_enable = GEN6_RC_CTL_RC6_ENABLE;
114 	else
115 		rc6->ctl_enable =
116 			GEN6_RC_CTL_HW_ENABLE |
117 			GEN6_RC_CTL_RC6_ENABLE |
118 			GEN6_RC_CTL_EI_MODE(1);
119 
120 	pg_enable =
121 		GEN9_RENDER_PG_ENABLE |
122 		GEN9_MEDIA_PG_ENABLE |
123 		GEN11_MEDIA_SAMPLER_PG_ENABLE;
124 
125 	if (GRAPHICS_VER(gt->i915) >= 12 && !IS_DG1(gt->i915)) {
126 		for (i = 0; i < I915_MAX_VCS; i++)
127 			if (HAS_ENGINE(gt, _VCS(i)))
128 				pg_enable |= (VDN_HCP_POWERGATE_ENABLE(i) |
129 					      VDN_MFX_POWERGATE_ENABLE(i));
130 	}
131 
132 	intel_uncore_write_fw(uncore, GEN9_PG_ENABLE, pg_enable);
133 }
134 
gen9_rc6_enable(struct intel_rc6 * rc6)135 static void gen9_rc6_enable(struct intel_rc6 *rc6)
136 {
137 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
138 	struct intel_engine_cs *engine;
139 	enum intel_engine_id id;
140 
141 	/* 2b: Program RC6 thresholds.*/
142 	if (GRAPHICS_VER(rc6_to_i915(rc6)) >= 11) {
143 		intel_uncore_write_fw(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 54 << 16 | 85);
144 		intel_uncore_write_fw(uncore, GEN10_MEDIA_WAKE_RATE_LIMIT, 150);
145 	} else if (IS_SKYLAKE(rc6_to_i915(rc6))) {
146 		/*
147 		 * WaRsDoubleRc6WrlWithCoarsePowerGating:skl Doubling WRL only
148 		 * when CPG is enabled
149 		 */
150 		intel_uncore_write_fw(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 108 << 16);
151 	} else {
152 		intel_uncore_write_fw(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 54 << 16);
153 	}
154 
155 	intel_uncore_write_fw(uncore, GEN6_RC_EVALUATION_INTERVAL, 125000); /* 12500 * 1280ns */
156 	intel_uncore_write_fw(uncore, GEN6_RC_IDLE_HYSTERSIS, 25); /* 25 * 1280ns */
157 	for_each_engine(engine, rc6_to_gt(rc6), id)
158 		intel_uncore_write_fw(uncore, RING_MAX_IDLE(engine->mmio_base), 10);
159 
160 	intel_uncore_write_fw(uncore, GUC_MAX_IDLE_COUNT, 0xA);
161 
162 	intel_uncore_write_fw(uncore, GEN6_RC_SLEEP, 0);
163 
164 	/*
165 	 * 2c: Program Coarse Power Gating Policies.
166 	 *
167 	 * Bspec's guidance is to use 25us (really 25 * 1280ns) here. What we
168 	 * use instead is a more conservative estimate for the maximum time
169 	 * it takes us to service a CS interrupt and submit a new ELSP - that
170 	 * is the time which the GPU is idle waiting for the CPU to select the
171 	 * next request to execute. If the idle hysteresis is less than that
172 	 * interrupt service latency, the hardware will automatically gate
173 	 * the power well and we will then incur the wake up cost on top of
174 	 * the service latency. A similar guide from plane_state is that we
175 	 * do not want the enable hysteresis to less than the wakeup latency.
176 	 *
177 	 * igt/gem_exec_nop/sequential provides a rough estimate for the
178 	 * service latency, and puts it around 10us for Broadwell (and other
179 	 * big core) and around 40us for Broxton (and other low power cores).
180 	 * [Note that for legacy ringbuffer submission, this is less than 1us!]
181 	 * However, the wakeup latency on Broxton is closer to 100us. To be
182 	 * conservative, we have to factor in a context switch on top (due
183 	 * to ksoftirqd).
184 	 */
185 	intel_uncore_write_fw(uncore, GEN9_MEDIA_PG_IDLE_HYSTERESIS, 250);
186 	intel_uncore_write_fw(uncore, GEN9_RENDER_PG_IDLE_HYSTERESIS, 250);
187 
188 	/* 3a: Enable RC6 */
189 	intel_uncore_write_fw(uncore, GEN6_RC6_THRESHOLD, 37500); /* 37.5/125ms per EI */
190 
191 	rc6->ctl_enable =
192 		GEN6_RC_CTL_HW_ENABLE |
193 		GEN6_RC_CTL_RC6_ENABLE |
194 		GEN6_RC_CTL_EI_MODE(1);
195 
196 	/*
197 	 * WaRsDisableCoarsePowerGating:skl,cnl
198 	 *   - Render/Media PG need to be disabled with RC6.
199 	 */
200 	if (!NEEDS_WaRsDisableCoarsePowerGating(rc6_to_i915(rc6)))
201 		intel_uncore_write_fw(uncore, GEN9_PG_ENABLE,
202 				      GEN9_RENDER_PG_ENABLE | GEN9_MEDIA_PG_ENABLE);
203 }
204 
gen8_rc6_enable(struct intel_rc6 * rc6)205 static void gen8_rc6_enable(struct intel_rc6 *rc6)
206 {
207 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
208 	struct intel_engine_cs *engine;
209 	enum intel_engine_id id;
210 
211 	/* 2b: Program RC6 thresholds.*/
212 	intel_uncore_write_fw(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 40 << 16);
213 	intel_uncore_write_fw(uncore, GEN6_RC_EVALUATION_INTERVAL, 125000); /* 12500 * 1280ns */
214 	intel_uncore_write_fw(uncore, GEN6_RC_IDLE_HYSTERSIS, 25); /* 25 * 1280ns */
215 	for_each_engine(engine, rc6_to_gt(rc6), id)
216 		intel_uncore_write_fw(uncore, RING_MAX_IDLE(engine->mmio_base), 10);
217 	intel_uncore_write_fw(uncore, GEN6_RC_SLEEP, 0);
218 	intel_uncore_write_fw(uncore, GEN6_RC6_THRESHOLD, 625); /* 800us/1.28 for TO */
219 
220 	/* 3: Enable RC6 */
221 	rc6->ctl_enable =
222 	    GEN6_RC_CTL_HW_ENABLE |
223 	    GEN7_RC_CTL_TO_MODE |
224 	    GEN6_RC_CTL_RC6_ENABLE;
225 }
226 
gen6_rc6_enable(struct intel_rc6 * rc6)227 static void gen6_rc6_enable(struct intel_rc6 *rc6)
228 {
229 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
230 	struct drm_i915_private *i915 = rc6_to_i915(rc6);
231 	struct intel_engine_cs *engine;
232 	enum intel_engine_id id;
233 	u32 rc6vids, rc6_mask;
234 	int ret;
235 
236 	intel_uncore_write_fw(uncore, GEN6_RC1_WAKE_RATE_LIMIT, 1000 << 16);
237 	intel_uncore_write_fw(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 40 << 16 | 30);
238 	intel_uncore_write_fw(uncore, GEN6_RC6pp_WAKE_RATE_LIMIT, 30);
239 	intel_uncore_write_fw(uncore, GEN6_RC_EVALUATION_INTERVAL, 125000);
240 	intel_uncore_write_fw(uncore, GEN6_RC_IDLE_HYSTERSIS, 25);
241 
242 	for_each_engine(engine, rc6_to_gt(rc6), id)
243 		intel_uncore_write_fw(uncore, RING_MAX_IDLE(engine->mmio_base), 10);
244 
245 	intel_uncore_write_fw(uncore, GEN6_RC_SLEEP, 0);
246 	intel_uncore_write_fw(uncore, GEN6_RC1e_THRESHOLD, 1000);
247 	intel_uncore_write_fw(uncore, GEN6_RC6_THRESHOLD, 50000);
248 	intel_uncore_write_fw(uncore, GEN6_RC6p_THRESHOLD, 150000);
249 	intel_uncore_write_fw(uncore, GEN6_RC6pp_THRESHOLD, 64000); /* unused */
250 
251 	/* We don't use those on Haswell */
252 	rc6_mask = GEN6_RC_CTL_RC6_ENABLE;
253 	if (HAS_RC6p(i915))
254 		rc6_mask |= GEN6_RC_CTL_RC6p_ENABLE;
255 	if (HAS_RC6pp(i915))
256 		rc6_mask |= GEN6_RC_CTL_RC6pp_ENABLE;
257 	rc6->ctl_enable =
258 	    rc6_mask |
259 	    GEN6_RC_CTL_EI_MODE(1) |
260 	    GEN6_RC_CTL_HW_ENABLE;
261 
262 	rc6vids = 0;
263 	ret = snb_pcode_read(rc6_to_gt(rc6)->uncore, GEN6_PCODE_READ_RC6VIDS, &rc6vids, NULL);
264 	if (GRAPHICS_VER(i915) == 6 && ret) {
265 		drm_dbg(&i915->drm, "Couldn't check for BIOS workaround\n");
266 	} else if (GRAPHICS_VER(i915) == 6 &&
267 		   (GEN6_DECODE_RC6_VID(rc6vids & 0xff) < 450)) {
268 		drm_dbg(&i915->drm,
269 			"You should update your BIOS. Correcting minimum rc6 voltage (%dmV->%dmV)\n",
270 			GEN6_DECODE_RC6_VID(rc6vids & 0xff), 450);
271 		rc6vids &= 0xffff00;
272 		rc6vids |= GEN6_ENCODE_RC6_VID(450);
273 		ret = snb_pcode_write(rc6_to_gt(rc6)->uncore, GEN6_PCODE_WRITE_RC6VIDS, rc6vids);
274 		if (ret)
275 			drm_err(&i915->drm,
276 				"Couldn't fix incorrect rc6 voltage\n");
277 	}
278 }
279 
280 /* Check that the pcbr address is not empty. */
chv_rc6_init(struct intel_rc6 * rc6)281 static int chv_rc6_init(struct intel_rc6 *rc6)
282 {
283 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
284 	struct drm_i915_private *i915 = rc6_to_i915(rc6);
285 	resource_size_t pctx_paddr, paddr;
286 	resource_size_t pctx_size = 32 * SZ_1K;
287 	u32 pcbr;
288 
289 	pcbr = intel_uncore_read(uncore, VLV_PCBR);
290 	if ((pcbr >> VLV_PCBR_ADDR_SHIFT) == 0) {
291 		drm_dbg(&i915->drm, "BIOS didn't set up PCBR, fixing up\n");
292 		paddr = i915->dsm.stolen.end + 1 - pctx_size;
293 		GEM_BUG_ON(paddr > U32_MAX);
294 
295 		pctx_paddr = (paddr & ~4095);
296 		intel_uncore_write(uncore, VLV_PCBR, pctx_paddr);
297 	}
298 
299 	return 0;
300 }
301 
vlv_rc6_init(struct intel_rc6 * rc6)302 static int vlv_rc6_init(struct intel_rc6 *rc6)
303 {
304 	struct drm_i915_private *i915 = rc6_to_i915(rc6);
305 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
306 	struct drm_i915_gem_object *pctx;
307 	resource_size_t pctx_paddr;
308 	resource_size_t pctx_size = 24 * SZ_1K;
309 	u32 pcbr;
310 
311 	pcbr = intel_uncore_read(uncore, VLV_PCBR);
312 	if (pcbr) {
313 		/* BIOS set it up already, grab the pre-alloc'd space */
314 		resource_size_t pcbr_offset;
315 
316 		pcbr_offset = (pcbr & ~4095) - i915->dsm.stolen.start;
317 		pctx = i915_gem_object_create_region_at(i915->mm.stolen_region,
318 							pcbr_offset,
319 							pctx_size,
320 							0);
321 		if (IS_ERR(pctx))
322 			return PTR_ERR(pctx);
323 
324 		goto out;
325 	}
326 
327 	drm_dbg(&i915->drm, "BIOS didn't set up PCBR, fixing up\n");
328 
329 	/*
330 	 * From the Gunit register HAS:
331 	 * The Gfx driver is expected to program this register and ensure
332 	 * proper allocation within Gfx stolen memory.  For example, this
333 	 * register should be programmed such than the PCBR range does not
334 	 * overlap with other ranges, such as the frame buffer, protected
335 	 * memory, or any other relevant ranges.
336 	 */
337 	pctx = i915_gem_object_create_stolen(i915, pctx_size);
338 	if (IS_ERR(pctx)) {
339 		drm_dbg(&i915->drm,
340 			"not enough stolen space for PCTX, disabling\n");
341 		return PTR_ERR(pctx);
342 	}
343 
344 	GEM_BUG_ON(range_overflows_end_t(u64,
345 					 i915->dsm.stolen.start,
346 					 pctx->stolen->start,
347 					 U32_MAX));
348 	pctx_paddr = i915->dsm.stolen.start + pctx->stolen->start;
349 	intel_uncore_write(uncore, VLV_PCBR, pctx_paddr);
350 
351 out:
352 	rc6->pctx = pctx;
353 	return 0;
354 }
355 
chv_rc6_enable(struct intel_rc6 * rc6)356 static void chv_rc6_enable(struct intel_rc6 *rc6)
357 {
358 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
359 	struct intel_engine_cs *engine;
360 	enum intel_engine_id id;
361 
362 	/* 2a: Program RC6 thresholds.*/
363 	intel_uncore_write_fw(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 40 << 16);
364 	intel_uncore_write_fw(uncore, GEN6_RC_EVALUATION_INTERVAL, 125000); /* 12500 * 1280ns */
365 	intel_uncore_write_fw(uncore, GEN6_RC_IDLE_HYSTERSIS, 25); /* 25 * 1280ns */
366 
367 	for_each_engine(engine, rc6_to_gt(rc6), id)
368 		intel_uncore_write_fw(uncore, RING_MAX_IDLE(engine->mmio_base), 10);
369 	intel_uncore_write_fw(uncore, GEN6_RC_SLEEP, 0);
370 
371 	/* TO threshold set to 500 us (0x186 * 1.28 us) */
372 	intel_uncore_write_fw(uncore, GEN6_RC6_THRESHOLD, 0x186);
373 
374 	/* Allows RC6 residency counter to work */
375 	intel_uncore_write_fw(uncore, VLV_COUNTER_CONTROL,
376 			      _MASKED_BIT_ENABLE(VLV_COUNT_RANGE_HIGH |
377 						 VLV_MEDIA_RC6_COUNT_EN |
378 						 VLV_RENDER_RC6_COUNT_EN));
379 
380 	/* 3: Enable RC6 */
381 	rc6->ctl_enable = GEN7_RC_CTL_TO_MODE;
382 }
383 
vlv_rc6_enable(struct intel_rc6 * rc6)384 static void vlv_rc6_enable(struct intel_rc6 *rc6)
385 {
386 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
387 	struct intel_engine_cs *engine;
388 	enum intel_engine_id id;
389 
390 	intel_uncore_write_fw(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 0x00280000);
391 	intel_uncore_write_fw(uncore, GEN6_RC_EVALUATION_INTERVAL, 125000);
392 	intel_uncore_write_fw(uncore, GEN6_RC_IDLE_HYSTERSIS, 25);
393 
394 	for_each_engine(engine, rc6_to_gt(rc6), id)
395 		intel_uncore_write_fw(uncore, RING_MAX_IDLE(engine->mmio_base), 10);
396 
397 	intel_uncore_write_fw(uncore, GEN6_RC6_THRESHOLD, 0x557);
398 
399 	/* Allows RC6 residency counter to work */
400 	intel_uncore_write_fw(uncore, VLV_COUNTER_CONTROL,
401 			      _MASKED_BIT_ENABLE(VLV_COUNT_RANGE_HIGH |
402 						 VLV_MEDIA_RC0_COUNT_EN |
403 						 VLV_RENDER_RC0_COUNT_EN |
404 						 VLV_MEDIA_RC6_COUNT_EN |
405 						 VLV_RENDER_RC6_COUNT_EN));
406 
407 	rc6->ctl_enable =
408 	    GEN7_RC_CTL_TO_MODE | VLV_RC_CTL_CTX_RST_PARALLEL;
409 }
410 
intel_check_bios_c6_setup(struct intel_rc6 * rc6)411 bool intel_check_bios_c6_setup(struct intel_rc6 *rc6)
412 {
413 	if (!rc6->bios_state_captured) {
414 		struct intel_uncore *uncore = rc6_to_uncore(rc6);
415 		intel_wakeref_t wakeref;
416 
417 		with_intel_runtime_pm(uncore->rpm, wakeref)
418 			rc6->bios_rc_state = intel_uncore_read(uncore, GEN6_RC_STATE);
419 
420 		rc6->bios_state_captured = true;
421 	}
422 
423 	return rc6->bios_rc_state & RC_SW_TARGET_STATE_MASK;
424 }
425 
bxt_check_bios_rc6_setup(struct intel_rc6 * rc6)426 static bool bxt_check_bios_rc6_setup(struct intel_rc6 *rc6)
427 {
428 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
429 	struct drm_i915_private *i915 = rc6_to_i915(rc6);
430 	u32 rc6_ctx_base, rc_ctl, rc_sw_target;
431 	bool enable_rc6 = true;
432 
433 	rc_ctl = intel_uncore_read(uncore, GEN6_RC_CONTROL);
434 	rc_sw_target = intel_uncore_read(uncore, GEN6_RC_STATE);
435 	rc_sw_target &= RC_SW_TARGET_STATE_MASK;
436 	rc_sw_target >>= RC_SW_TARGET_STATE_SHIFT;
437 	drm_dbg(&i915->drm, "BIOS enabled RC states: "
438 			 "HW_CTRL %s HW_RC6 %s SW_TARGET_STATE %x\n",
439 			 str_on_off(rc_ctl & GEN6_RC_CTL_HW_ENABLE),
440 			 str_on_off(rc_ctl & GEN6_RC_CTL_RC6_ENABLE),
441 			 rc_sw_target);
442 
443 	if (!(intel_uncore_read(uncore, RC6_LOCATION) & RC6_CTX_IN_DRAM)) {
444 		drm_dbg(&i915->drm, "RC6 Base location not set properly.\n");
445 		enable_rc6 = false;
446 	}
447 
448 	/*
449 	 * The exact context size is not known for BXT, so assume a page size
450 	 * for this check.
451 	 */
452 	rc6_ctx_base =
453 		intel_uncore_read(uncore, RC6_CTX_BASE) & RC6_CTX_BASE_MASK;
454 	if (!(rc6_ctx_base >= i915->dsm.reserved.start &&
455 	      rc6_ctx_base + PAGE_SIZE < i915->dsm.reserved.end)) {
456 		drm_dbg(&i915->drm, "RC6 Base address not as expected.\n");
457 		enable_rc6 = false;
458 	}
459 
460 	if (!((intel_uncore_read(uncore, PWRCTX_MAXCNT(RENDER_RING_BASE)) & IDLE_TIME_MASK) > 1 &&
461 	      (intel_uncore_read(uncore, PWRCTX_MAXCNT(GEN6_BSD_RING_BASE)) & IDLE_TIME_MASK) > 1 &&
462 	      (intel_uncore_read(uncore, PWRCTX_MAXCNT(BLT_RING_BASE)) & IDLE_TIME_MASK) > 1 &&
463 	      (intel_uncore_read(uncore, PWRCTX_MAXCNT(VEBOX_RING_BASE)) & IDLE_TIME_MASK) > 1)) {
464 		drm_dbg(&i915->drm,
465 			"Engine Idle wait time not set properly.\n");
466 		enable_rc6 = false;
467 	}
468 
469 	if (!intel_uncore_read(uncore, GEN8_PUSHBUS_CONTROL) ||
470 	    !intel_uncore_read(uncore, GEN8_PUSHBUS_ENABLE) ||
471 	    !intel_uncore_read(uncore, GEN8_PUSHBUS_SHIFT)) {
472 		drm_dbg(&i915->drm, "Pushbus not setup properly.\n");
473 		enable_rc6 = false;
474 	}
475 
476 	if (!intel_uncore_read(uncore, GEN6_GFXPAUSE)) {
477 		drm_dbg(&i915->drm, "GFX pause not setup properly.\n");
478 		enable_rc6 = false;
479 	}
480 
481 	if (!intel_uncore_read(uncore, GEN8_MISC_CTRL0)) {
482 		drm_dbg(&i915->drm, "GPM control not setup properly.\n");
483 		enable_rc6 = false;
484 	}
485 
486 	return enable_rc6;
487 }
488 
rc6_supported(struct intel_rc6 * rc6)489 static bool rc6_supported(struct intel_rc6 *rc6)
490 {
491 	struct drm_i915_private *i915 = rc6_to_i915(rc6);
492 	struct intel_gt *gt = rc6_to_gt(rc6);
493 
494 	if (!HAS_RC6(i915))
495 		return false;
496 
497 	if (intel_vgpu_active(i915))
498 		return false;
499 
500 	if (is_mock_gt(rc6_to_gt(rc6)))
501 		return false;
502 
503 	if (IS_GEN9_LP(i915) && !bxt_check_bios_rc6_setup(rc6)) {
504 		drm_notice(&i915->drm,
505 			   "RC6 and powersaving disabled by BIOS\n");
506 		return false;
507 	}
508 
509 	if (IS_METEORLAKE(gt->i915) &&
510 	    !intel_check_bios_c6_setup(rc6)) {
511 		drm_notice(&i915->drm,
512 			   "C6 disabled by BIOS\n");
513 		return false;
514 	}
515 
516 	if (IS_MTL_MEDIA_STEP(gt->i915, STEP_A0, STEP_B0) &&
517 	    gt->type == GT_MEDIA) {
518 		drm_notice(&i915->drm,
519 			   "Media RC6 disabled on A step\n");
520 		return false;
521 	}
522 
523 	return true;
524 }
525 
rpm_get(struct intel_rc6 * rc6)526 static void rpm_get(struct intel_rc6 *rc6)
527 {
528 	GEM_BUG_ON(rc6->wakeref);
529 	pm_runtime_get_sync(rc6_to_i915(rc6)->drm.dev);
530 	rc6->wakeref = true;
531 }
532 
rpm_put(struct intel_rc6 * rc6)533 static void rpm_put(struct intel_rc6 *rc6)
534 {
535 	GEM_BUG_ON(!rc6->wakeref);
536 	pm_runtime_put(rc6_to_i915(rc6)->drm.dev);
537 	rc6->wakeref = false;
538 }
539 
pctx_corrupted(struct intel_rc6 * rc6)540 static bool pctx_corrupted(struct intel_rc6 *rc6)
541 {
542 	struct drm_i915_private *i915 = rc6_to_i915(rc6);
543 
544 	if (!NEEDS_RC6_CTX_CORRUPTION_WA(i915))
545 		return false;
546 
547 	if (intel_uncore_read(rc6_to_uncore(rc6), GEN8_RC6_CTX_INFO))
548 		return false;
549 
550 	drm_notice(&i915->drm,
551 		   "RC6 context corruption, disabling runtime power management\n");
552 	return true;
553 }
554 
__intel_rc6_disable(struct intel_rc6 * rc6)555 static void __intel_rc6_disable(struct intel_rc6 *rc6)
556 {
557 	struct drm_i915_private *i915 = rc6_to_i915(rc6);
558 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
559 	struct intel_gt *gt = rc6_to_gt(rc6);
560 
561 	/* Take control of RC6 back from GuC */
562 	intel_guc_rc_disable(&gt->uc.guc);
563 
564 	intel_uncore_forcewake_get(uncore, FORCEWAKE_ALL);
565 	if (GRAPHICS_VER(i915) >= 9)
566 		intel_uncore_write_fw(uncore, GEN9_PG_ENABLE, 0);
567 	intel_uncore_write_fw(uncore, GEN6_RC_CONTROL, 0);
568 	intel_uncore_write_fw(uncore, GEN6_RC_STATE, 0);
569 	intel_uncore_forcewake_put(uncore, FORCEWAKE_ALL);
570 }
571 
rc6_res_reg_init(struct intel_rc6 * rc6)572 static void rc6_res_reg_init(struct intel_rc6 *rc6)
573 {
574 	i915_reg_t res_reg[INTEL_RC6_RES_MAX] = {
575 		[0 ... INTEL_RC6_RES_MAX - 1] = INVALID_MMIO_REG,
576 	};
577 
578 	switch (rc6_to_gt(rc6)->type) {
579 	case GT_MEDIA:
580 		res_reg[INTEL_RC6_RES_RC6] = MTL_MEDIA_MC6;
581 		break;
582 	default:
583 		res_reg[INTEL_RC6_RES_RC6_LOCKED] = GEN6_GT_GFX_RC6_LOCKED;
584 		res_reg[INTEL_RC6_RES_RC6] = GEN6_GT_GFX_RC6;
585 		res_reg[INTEL_RC6_RES_RC6p] = GEN6_GT_GFX_RC6p;
586 		res_reg[INTEL_RC6_RES_RC6pp] = GEN6_GT_GFX_RC6pp;
587 		break;
588 	}
589 
590 	memcpy(rc6->res_reg, res_reg, sizeof(res_reg));
591 }
592 
intel_rc6_init(struct intel_rc6 * rc6)593 void intel_rc6_init(struct intel_rc6 *rc6)
594 {
595 	struct drm_i915_private *i915 = rc6_to_i915(rc6);
596 	int err;
597 
598 	/* Disable runtime-pm until we can save the GPU state with rc6 pctx */
599 	rpm_get(rc6);
600 
601 	if (!rc6_supported(rc6))
602 		return;
603 
604 	rc6_res_reg_init(rc6);
605 
606 	if (IS_CHERRYVIEW(i915))
607 		err = chv_rc6_init(rc6);
608 	else if (IS_VALLEYVIEW(i915))
609 		err = vlv_rc6_init(rc6);
610 	else
611 		err = 0;
612 
613 	/* Sanitize rc6, ensure it is disabled before we are ready. */
614 	__intel_rc6_disable(rc6);
615 
616 	rc6->supported = err == 0;
617 }
618 
intel_rc6_sanitize(struct intel_rc6 * rc6)619 void intel_rc6_sanitize(struct intel_rc6 *rc6)
620 {
621 	memset(rc6->prev_hw_residency, 0, sizeof(rc6->prev_hw_residency));
622 
623 	if (rc6->enabled) { /* unbalanced suspend/resume */
624 		rpm_get(rc6);
625 		rc6->enabled = false;
626 	}
627 
628 	if (rc6->supported)
629 		__intel_rc6_disable(rc6);
630 }
631 
intel_rc6_enable(struct intel_rc6 * rc6)632 void intel_rc6_enable(struct intel_rc6 *rc6)
633 {
634 	struct drm_i915_private *i915 = rc6_to_i915(rc6);
635 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
636 
637 	if (!rc6->supported)
638 		return;
639 
640 	GEM_BUG_ON(rc6->enabled);
641 
642 	intel_uncore_forcewake_get(uncore, FORCEWAKE_ALL);
643 
644 	if (IS_CHERRYVIEW(i915))
645 		chv_rc6_enable(rc6);
646 	else if (IS_VALLEYVIEW(i915))
647 		vlv_rc6_enable(rc6);
648 	else if (GRAPHICS_VER(i915) >= 11)
649 		gen11_rc6_enable(rc6);
650 	else if (GRAPHICS_VER(i915) >= 9)
651 		gen9_rc6_enable(rc6);
652 	else if (IS_BROADWELL(i915))
653 		gen8_rc6_enable(rc6);
654 	else if (GRAPHICS_VER(i915) >= 6)
655 		gen6_rc6_enable(rc6);
656 
657 	rc6->manual = rc6->ctl_enable & GEN6_RC_CTL_RC6_ENABLE;
658 	if (NEEDS_RC6_CTX_CORRUPTION_WA(i915))
659 		rc6->ctl_enable = 0;
660 
661 	intel_uncore_forcewake_put(uncore, FORCEWAKE_ALL);
662 
663 	if (unlikely(pctx_corrupted(rc6)))
664 		return;
665 
666 	/* rc6 is ready, runtime-pm is go! */
667 	rpm_put(rc6);
668 	rc6->enabled = true;
669 }
670 
intel_rc6_unpark(struct intel_rc6 * rc6)671 void intel_rc6_unpark(struct intel_rc6 *rc6)
672 {
673 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
674 
675 	if (!rc6->enabled)
676 		return;
677 
678 	/* Restore HW timers for automatic RC6 entry while busy */
679 	intel_uncore_write_fw(uncore, GEN6_RC_CONTROL, rc6->ctl_enable);
680 }
681 
intel_rc6_park(struct intel_rc6 * rc6)682 void intel_rc6_park(struct intel_rc6 *rc6)
683 {
684 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
685 	unsigned int target;
686 
687 	if (!rc6->enabled)
688 		return;
689 
690 	if (unlikely(pctx_corrupted(rc6))) {
691 		intel_rc6_disable(rc6);
692 		return;
693 	}
694 
695 	if (!rc6->manual)
696 		return;
697 
698 	/* Turn off the HW timers and go directly to rc6 */
699 	intel_uncore_write_fw(uncore, GEN6_RC_CONTROL, GEN6_RC_CTL_RC6_ENABLE);
700 
701 	if (HAS_RC6pp(rc6_to_i915(rc6)))
702 		target = 0x6; /* deepest rc6 */
703 	else if (HAS_RC6p(rc6_to_i915(rc6)))
704 		target = 0x5; /* deep rc6 */
705 	else
706 		target = 0x4; /* normal rc6 */
707 	intel_uncore_write_fw(uncore, GEN6_RC_STATE, target << RC_SW_TARGET_STATE_SHIFT);
708 }
709 
intel_rc6_disable(struct intel_rc6 * rc6)710 void intel_rc6_disable(struct intel_rc6 *rc6)
711 {
712 	if (!rc6->enabled)
713 		return;
714 
715 	rpm_get(rc6);
716 	rc6->enabled = false;
717 
718 	__intel_rc6_disable(rc6);
719 }
720 
intel_rc6_fini(struct intel_rc6 * rc6)721 void intel_rc6_fini(struct intel_rc6 *rc6)
722 {
723 	struct drm_i915_gem_object *pctx;
724 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
725 
726 	intel_rc6_disable(rc6);
727 
728 	/* We want the BIOS C6 state preserved across loads for MTL */
729 	if (IS_METEORLAKE(rc6_to_i915(rc6)) && rc6->bios_state_captured)
730 		intel_uncore_write_fw(uncore, GEN6_RC_STATE, rc6->bios_rc_state);
731 
732 	pctx = fetch_and_zero(&rc6->pctx);
733 	if (pctx)
734 		i915_gem_object_put(pctx);
735 
736 	if (rc6->wakeref)
737 		rpm_put(rc6);
738 }
739 
vlv_residency_raw(struct intel_uncore * uncore,const i915_reg_t reg)740 static u64 vlv_residency_raw(struct intel_uncore *uncore, const i915_reg_t reg)
741 {
742 	u32 lower, upper, tmp;
743 	int loop = 2;
744 
745 	/*
746 	 * The register accessed do not need forcewake. We borrow
747 	 * uncore lock to prevent concurrent access to range reg.
748 	 */
749 	lockdep_assert_held(&uncore->lock);
750 
751 	/*
752 	 * vlv and chv residency counters are 40 bits in width.
753 	 * With a control bit, we can choose between upper or lower
754 	 * 32bit window into this counter.
755 	 *
756 	 * Although we always use the counter in high-range mode elsewhere,
757 	 * userspace may attempt to read the value before rc6 is initialised,
758 	 * before we have set the default VLV_COUNTER_CONTROL value. So always
759 	 * set the high bit to be safe.
760 	 */
761 	intel_uncore_write_fw(uncore, VLV_COUNTER_CONTROL,
762 			      _MASKED_BIT_ENABLE(VLV_COUNT_RANGE_HIGH));
763 	upper = intel_uncore_read_fw(uncore, reg);
764 	do {
765 		tmp = upper;
766 
767 		intel_uncore_write_fw(uncore, VLV_COUNTER_CONTROL,
768 				      _MASKED_BIT_DISABLE(VLV_COUNT_RANGE_HIGH));
769 		lower = intel_uncore_read_fw(uncore, reg);
770 
771 		intel_uncore_write_fw(uncore, VLV_COUNTER_CONTROL,
772 				      _MASKED_BIT_ENABLE(VLV_COUNT_RANGE_HIGH));
773 		upper = intel_uncore_read_fw(uncore, reg);
774 	} while (upper != tmp && --loop);
775 
776 	/*
777 	 * Everywhere else we always use VLV_COUNTER_CONTROL with the
778 	 * VLV_COUNT_RANGE_HIGH bit set - so it is safe to leave it set
779 	 * now.
780 	 */
781 
782 	return lower | (u64)upper << 8;
783 }
784 
intel_rc6_residency_ns(struct intel_rc6 * rc6,enum intel_rc6_res_type id)785 u64 intel_rc6_residency_ns(struct intel_rc6 *rc6, enum intel_rc6_res_type id)
786 {
787 	struct drm_i915_private *i915 = rc6_to_i915(rc6);
788 	struct intel_uncore *uncore = rc6_to_uncore(rc6);
789 	u64 time_hw, prev_hw, overflow_hw;
790 	i915_reg_t reg = rc6->res_reg[id];
791 	unsigned int fw_domains;
792 	unsigned long flags;
793 	u32 mul, div;
794 
795 	if (!rc6->supported)
796 		return 0;
797 
798 	fw_domains = intel_uncore_forcewake_for_reg(uncore, reg, FW_REG_READ);
799 
800 	spin_lock_irqsave(&uncore->lock, flags);
801 	intel_uncore_forcewake_get__locked(uncore, fw_domains);
802 
803 	/* On VLV and CHV, residency time is in CZ units rather than 1.28us */
804 	if (IS_VALLEYVIEW(i915) || IS_CHERRYVIEW(i915)) {
805 		mul = 1000000;
806 		div = i915->czclk_freq;
807 		overflow_hw = BIT_ULL(40);
808 		time_hw = vlv_residency_raw(uncore, reg);
809 	} else {
810 		/* 833.33ns units on Gen9LP, 1.28us elsewhere. */
811 		if (IS_GEN9_LP(i915)) {
812 			mul = 10000;
813 			div = 12;
814 		} else {
815 			mul = 1280;
816 			div = 1;
817 		}
818 
819 		overflow_hw = BIT_ULL(32);
820 		time_hw = intel_uncore_read_fw(uncore, reg);
821 	}
822 
823 	/*
824 	 * Counter wrap handling.
825 	 *
826 	 * Store previous hw counter values for counter wrap-around handling. But
827 	 * relying on a sufficient frequency of queries otherwise counters can still wrap.
828 	 */
829 	prev_hw = rc6->prev_hw_residency[id];
830 	rc6->prev_hw_residency[id] = time_hw;
831 
832 	/* RC6 delta from last sample. */
833 	if (time_hw >= prev_hw)
834 		time_hw -= prev_hw;
835 	else
836 		time_hw += overflow_hw - prev_hw;
837 
838 	/* Add delta to RC6 extended raw driver copy. */
839 	time_hw += rc6->cur_residency[id];
840 	rc6->cur_residency[id] = time_hw;
841 
842 	intel_uncore_forcewake_put__locked(uncore, fw_domains);
843 	spin_unlock_irqrestore(&uncore->lock, flags);
844 
845 	return mul_u64_u32_div(time_hw, mul, div);
846 }
847 
intel_rc6_residency_us(struct intel_rc6 * rc6,enum intel_rc6_res_type id)848 u64 intel_rc6_residency_us(struct intel_rc6 *rc6, enum intel_rc6_res_type id)
849 {
850 	return DIV_ROUND_UP_ULL(intel_rc6_residency_ns(rc6, id), 1000);
851 }
852 
intel_rc6_print_residency(struct seq_file * m,const char * title,enum intel_rc6_res_type id)853 void intel_rc6_print_residency(struct seq_file *m, const char *title,
854 			       enum intel_rc6_res_type id)
855 {
856 	struct intel_gt *gt = m->private;
857 	i915_reg_t reg = gt->rc6.res_reg[id];
858 	intel_wakeref_t wakeref;
859 
860 	with_intel_runtime_pm(gt->uncore->rpm, wakeref)
861 		seq_printf(m, "%s %u (%llu us)\n", title,
862 			   intel_uncore_read(gt->uncore, reg),
863 			   intel_rc6_residency_us(&gt->rc6, id));
864 }
865 
866 #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
867 #include "selftest_rc6.c"
868 #endif
869