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
41static struct intel_gt *rc6_to_gt(struct intel_rc6 *rc6)
42{
43 return container_of(rc6, struct intel_gt, rc6);
44}
45
46static struct intel_uncore *rc6_to_uncore(struct intel_rc6 *rc)
47{
48 return rc6_to_gt(rc6: rc)->uncore;
49}
50
51static struct drm_i915_private *rc6_to_i915(struct intel_rc6 *rc)
52{
53 return rc6_to_gt(rc6: rc)->i915;
54}
55
56static 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(uc: &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(guc: &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 /*
121 * BSpec 52698 - Render powergating must be off.
122 * FIXME BSpec is outdated, disabling powergating for MTL is just
123 * temporary wa and should be removed after fixing real cause
124 * of forcewake timeouts.
125 */
126 if (IS_GFX_GT_IP_RANGE(gt, IP_VER(12, 70), IP_VER(12, 74)))
127 pg_enable =
128 GEN9_MEDIA_PG_ENABLE |
129 GEN11_MEDIA_SAMPLER_PG_ENABLE;
130 else
131 pg_enable =
132 GEN9_RENDER_PG_ENABLE |
133 GEN9_MEDIA_PG_ENABLE |
134 GEN11_MEDIA_SAMPLER_PG_ENABLE;
135
136 if (GRAPHICS_VER(gt->i915) >= 12) {
137 for (i = 0; i < I915_MAX_VCS; i++)
138 if (HAS_ENGINE(gt, _VCS(i)))
139 pg_enable |= (VDN_HCP_POWERGATE_ENABLE(i) |
140 VDN_MFX_POWERGATE_ENABLE(i));
141 }
142
143 intel_uncore_write_fw(uncore, GEN9_PG_ENABLE, pg_enable);
144}
145
146static void gen9_rc6_enable(struct intel_rc6 *rc6)
147{
148 struct intel_uncore *uncore = rc6_to_uncore(rc: rc6);
149 struct intel_engine_cs *engine;
150 enum intel_engine_id id;
151
152 /* 2b: Program RC6 thresholds.*/
153 if (GRAPHICS_VER(rc6_to_i915(rc6)) >= 11) {
154 intel_uncore_write_fw(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 54 << 16 | 85);
155 intel_uncore_write_fw(uncore, GEN10_MEDIA_WAKE_RATE_LIMIT, 150);
156 } else if (IS_SKYLAKE(rc6_to_i915(rc6))) {
157 /*
158 * WaRsDoubleRc6WrlWithCoarsePowerGating:skl Doubling WRL only
159 * when CPG is enabled
160 */
161 intel_uncore_write_fw(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 108 << 16);
162 } else {
163 intel_uncore_write_fw(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 54 << 16);
164 }
165
166 intel_uncore_write_fw(uncore, GEN6_RC_EVALUATION_INTERVAL, 125000); /* 12500 * 1280ns */
167 intel_uncore_write_fw(uncore, GEN6_RC_IDLE_HYSTERSIS, 25); /* 25 * 1280ns */
168 for_each_engine(engine, rc6_to_gt(rc6), id)
169 intel_uncore_write_fw(uncore, RING_MAX_IDLE(engine->mmio_base), 10);
170
171 intel_uncore_write_fw(uncore, GUC_MAX_IDLE_COUNT, 0xA);
172
173 intel_uncore_write_fw(uncore, GEN6_RC_SLEEP, 0);
174
175 /*
176 * 2c: Program Coarse Power Gating Policies.
177 *
178 * Bspec's guidance is to use 25us (really 25 * 1280ns) here. What we
179 * use instead is a more conservative estimate for the maximum time
180 * it takes us to service a CS interrupt and submit a new ELSP - that
181 * is the time which the GPU is idle waiting for the CPU to select the
182 * next request to execute. If the idle hysteresis is less than that
183 * interrupt service latency, the hardware will automatically gate
184 * the power well and we will then incur the wake up cost on top of
185 * the service latency. A similar guide from plane_state is that we
186 * do not want the enable hysteresis to less than the wakeup latency.
187 *
188 * igt/gem_exec_nop/sequential provides a rough estimate for the
189 * service latency, and puts it around 10us for Broadwell (and other
190 * big core) and around 40us for Broxton (and other low power cores).
191 * [Note that for legacy ringbuffer submission, this is less than 1us!]
192 * However, the wakeup latency on Broxton is closer to 100us. To be
193 * conservative, we have to factor in a context switch on top (due
194 * to ksoftirqd).
195 */
196 intel_uncore_write_fw(uncore, GEN9_MEDIA_PG_IDLE_HYSTERESIS, 250);
197 intel_uncore_write_fw(uncore, GEN9_RENDER_PG_IDLE_HYSTERESIS, 250);
198
199 /* 3a: Enable RC6 */
200 intel_uncore_write_fw(uncore, GEN6_RC6_THRESHOLD, 37500); /* 37.5/125ms per EI */
201
202 rc6->ctl_enable =
203 GEN6_RC_CTL_HW_ENABLE |
204 GEN6_RC_CTL_RC6_ENABLE |
205 GEN6_RC_CTL_EI_MODE(1);
206
207 /*
208 * WaRsDisableCoarsePowerGating:skl,cnl
209 * - Render/Media PG need to be disabled with RC6.
210 */
211 if (!NEEDS_WaRsDisableCoarsePowerGating(rc6_to_i915(rc6)))
212 intel_uncore_write_fw(uncore, GEN9_PG_ENABLE,
213 GEN9_RENDER_PG_ENABLE | GEN9_MEDIA_PG_ENABLE);
214}
215
216static void gen8_rc6_enable(struct intel_rc6 *rc6)
217{
218 struct intel_uncore *uncore = rc6_to_uncore(rc: rc6);
219 struct intel_engine_cs *engine;
220 enum intel_engine_id id;
221
222 /* 2b: Program RC6 thresholds.*/
223 intel_uncore_write_fw(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 40 << 16);
224 intel_uncore_write_fw(uncore, GEN6_RC_EVALUATION_INTERVAL, 125000); /* 12500 * 1280ns */
225 intel_uncore_write_fw(uncore, GEN6_RC_IDLE_HYSTERSIS, 25); /* 25 * 1280ns */
226 for_each_engine(engine, rc6_to_gt(rc6), id)
227 intel_uncore_write_fw(uncore, RING_MAX_IDLE(engine->mmio_base), 10);
228 intel_uncore_write_fw(uncore, GEN6_RC_SLEEP, 0);
229 intel_uncore_write_fw(uncore, GEN6_RC6_THRESHOLD, 625); /* 800us/1.28 for TO */
230
231 /* 3: Enable RC6 */
232 rc6->ctl_enable =
233 GEN6_RC_CTL_HW_ENABLE |
234 GEN7_RC_CTL_TO_MODE |
235 GEN6_RC_CTL_RC6_ENABLE;
236}
237
238static void gen6_rc6_enable(struct intel_rc6 *rc6)
239{
240 struct intel_uncore *uncore = rc6_to_uncore(rc: rc6);
241 struct drm_i915_private *i915 = rc6_to_i915(rc: rc6);
242 struct intel_engine_cs *engine;
243 enum intel_engine_id id;
244 u32 rc6vids, rc6_mask;
245 int ret;
246
247 intel_uncore_write_fw(uncore, GEN6_RC1_WAKE_RATE_LIMIT, 1000 << 16);
248 intel_uncore_write_fw(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 40 << 16 | 30);
249 intel_uncore_write_fw(uncore, GEN6_RC6pp_WAKE_RATE_LIMIT, 30);
250 intel_uncore_write_fw(uncore, GEN6_RC_EVALUATION_INTERVAL, 125000);
251 intel_uncore_write_fw(uncore, GEN6_RC_IDLE_HYSTERSIS, 25);
252
253 for_each_engine(engine, rc6_to_gt(rc6), id)
254 intel_uncore_write_fw(uncore, RING_MAX_IDLE(engine->mmio_base), 10);
255
256 intel_uncore_write_fw(uncore, GEN6_RC_SLEEP, 0);
257 intel_uncore_write_fw(uncore, GEN6_RC1e_THRESHOLD, 1000);
258 intel_uncore_write_fw(uncore, GEN6_RC6_THRESHOLD, 50000);
259 intel_uncore_write_fw(uncore, GEN6_RC6p_THRESHOLD, 150000);
260 intel_uncore_write_fw(uncore, GEN6_RC6pp_THRESHOLD, 64000); /* unused */
261
262 /* We don't use those on Haswell */
263 rc6_mask = GEN6_RC_CTL_RC6_ENABLE;
264 if (HAS_RC6p(i915))
265 rc6_mask |= GEN6_RC_CTL_RC6p_ENABLE;
266 if (HAS_RC6pp(i915))
267 rc6_mask |= GEN6_RC_CTL_RC6pp_ENABLE;
268 rc6->ctl_enable =
269 rc6_mask |
270 GEN6_RC_CTL_EI_MODE(1) |
271 GEN6_RC_CTL_HW_ENABLE;
272
273 rc6vids = 0;
274 ret = snb_pcode_read(uncore: rc6_to_gt(rc6)->uncore, GEN6_PCODE_READ_RC6VIDS, val: &rc6vids, NULL);
275 if (GRAPHICS_VER(i915) == 6 && ret) {
276 drm_dbg(&i915->drm, "Couldn't check for BIOS workaround\n");
277 } else if (GRAPHICS_VER(i915) == 6 &&
278 (GEN6_DECODE_RC6_VID(rc6vids & 0xff) < 450)) {
279 drm_dbg(&i915->drm,
280 "You should update your BIOS. Correcting minimum rc6 voltage (%dmV->%dmV)\n",
281 GEN6_DECODE_RC6_VID(rc6vids & 0xff), 450);
282 rc6vids &= 0xffff00;
283 rc6vids |= GEN6_ENCODE_RC6_VID(450);
284 ret = snb_pcode_write(rc6_to_gt(rc6)->uncore, GEN6_PCODE_WRITE_RC6VIDS, rc6vids);
285 if (ret)
286 drm_err(&i915->drm,
287 "Couldn't fix incorrect rc6 voltage\n");
288 }
289}
290
291/* Check that the pcbr address is not empty. */
292static int chv_rc6_init(struct intel_rc6 *rc6)
293{
294 struct intel_uncore *uncore = rc6_to_uncore(rc: rc6);
295 struct drm_i915_private *i915 = rc6_to_i915(rc: rc6);
296 resource_size_t pctx_paddr, paddr;
297 resource_size_t pctx_size = 32 * SZ_1K;
298 u32 pcbr;
299
300 pcbr = intel_uncore_read(uncore, VLV_PCBR);
301 if ((pcbr >> VLV_PCBR_ADDR_SHIFT) == 0) {
302 drm_dbg(&i915->drm, "BIOS didn't set up PCBR, fixing up\n");
303 paddr = i915->dsm.stolen.end + 1 - pctx_size;
304 GEM_BUG_ON(paddr > U32_MAX);
305
306 pctx_paddr = (paddr & ~4095);
307 intel_uncore_write(uncore, VLV_PCBR, val: pctx_paddr);
308 }
309
310 return 0;
311}
312
313static int vlv_rc6_init(struct intel_rc6 *rc6)
314{
315 struct drm_i915_private *i915 = rc6_to_i915(rc: rc6);
316 struct intel_uncore *uncore = rc6_to_uncore(rc: rc6);
317 struct drm_i915_gem_object *pctx;
318 resource_size_t pctx_paddr;
319 resource_size_t pctx_size = 24 * SZ_1K;
320 u32 pcbr;
321
322 pcbr = intel_uncore_read(uncore, VLV_PCBR);
323 if (pcbr) {
324 /* BIOS set it up already, grab the pre-alloc'd space */
325 resource_size_t pcbr_offset;
326
327 pcbr_offset = (pcbr & ~4095) - i915->dsm.stolen.start;
328 pctx = i915_gem_object_create_region_at(mem: i915->mm.stolen_region,
329 offset: pcbr_offset,
330 size: pctx_size,
331 flags: 0);
332 if (IS_ERR(ptr: pctx))
333 return PTR_ERR(ptr: pctx);
334
335 goto out;
336 }
337
338 drm_dbg(&i915->drm, "BIOS didn't set up PCBR, fixing up\n");
339
340 /*
341 * From the Gunit register HAS:
342 * The Gfx driver is expected to program this register and ensure
343 * proper allocation within Gfx stolen memory. For example, this
344 * register should be programmed such than the PCBR range does not
345 * overlap with other ranges, such as the frame buffer, protected
346 * memory, or any other relevant ranges.
347 */
348 pctx = i915_gem_object_create_stolen(dev_priv: i915, size: pctx_size);
349 if (IS_ERR(ptr: pctx)) {
350 drm_dbg(&i915->drm,
351 "not enough stolen space for PCTX, disabling\n");
352 return PTR_ERR(ptr: pctx);
353 }
354
355 GEM_BUG_ON(range_overflows_end_t(u64,
356 i915->dsm.stolen.start,
357 pctx->stolen->start,
358 U32_MAX));
359 pctx_paddr = i915->dsm.stolen.start + pctx->stolen->start;
360 intel_uncore_write(uncore, VLV_PCBR, val: pctx_paddr);
361
362out:
363 rc6->pctx = pctx;
364 return 0;
365}
366
367static void chv_rc6_enable(struct intel_rc6 *rc6)
368{
369 struct intel_uncore *uncore = rc6_to_uncore(rc: rc6);
370 struct intel_engine_cs *engine;
371 enum intel_engine_id id;
372
373 /* 2a: Program RC6 thresholds.*/
374 intel_uncore_write_fw(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 40 << 16);
375 intel_uncore_write_fw(uncore, GEN6_RC_EVALUATION_INTERVAL, 125000); /* 12500 * 1280ns */
376 intel_uncore_write_fw(uncore, GEN6_RC_IDLE_HYSTERSIS, 25); /* 25 * 1280ns */
377
378 for_each_engine(engine, rc6_to_gt(rc6), id)
379 intel_uncore_write_fw(uncore, RING_MAX_IDLE(engine->mmio_base), 10);
380 intel_uncore_write_fw(uncore, GEN6_RC_SLEEP, 0);
381
382 /* TO threshold set to 500 us (0x186 * 1.28 us) */
383 intel_uncore_write_fw(uncore, GEN6_RC6_THRESHOLD, 0x186);
384
385 /* Allows RC6 residency counter to work */
386 intel_uncore_write_fw(uncore, VLV_COUNTER_CONTROL,
387 _MASKED_BIT_ENABLE(VLV_COUNT_RANGE_HIGH |
388 VLV_MEDIA_RC6_COUNT_EN |
389 VLV_RENDER_RC6_COUNT_EN));
390
391 /* 3: Enable RC6 */
392 rc6->ctl_enable = GEN7_RC_CTL_TO_MODE;
393}
394
395static void vlv_rc6_enable(struct intel_rc6 *rc6)
396{
397 struct intel_uncore *uncore = rc6_to_uncore(rc: rc6);
398 struct intel_engine_cs *engine;
399 enum intel_engine_id id;
400
401 intel_uncore_write_fw(uncore, GEN6_RC6_WAKE_RATE_LIMIT, 0x00280000);
402 intel_uncore_write_fw(uncore, GEN6_RC_EVALUATION_INTERVAL, 125000);
403 intel_uncore_write_fw(uncore, GEN6_RC_IDLE_HYSTERSIS, 25);
404
405 for_each_engine(engine, rc6_to_gt(rc6), id)
406 intel_uncore_write_fw(uncore, RING_MAX_IDLE(engine->mmio_base), 10);
407
408 intel_uncore_write_fw(uncore, GEN6_RC6_THRESHOLD, 0x557);
409
410 /* Allows RC6 residency counter to work */
411 intel_uncore_write_fw(uncore, VLV_COUNTER_CONTROL,
412 _MASKED_BIT_ENABLE(VLV_COUNT_RANGE_HIGH |
413 VLV_MEDIA_RC0_COUNT_EN |
414 VLV_RENDER_RC0_COUNT_EN |
415 VLV_MEDIA_RC6_COUNT_EN |
416 VLV_RENDER_RC6_COUNT_EN));
417
418 rc6->ctl_enable =
419 GEN7_RC_CTL_TO_MODE | VLV_RC_CTL_CTX_RST_PARALLEL;
420}
421
422bool intel_check_bios_c6_setup(struct intel_rc6 *rc6)
423{
424 if (!rc6->bios_state_captured) {
425 struct intel_uncore *uncore = rc6_to_uncore(rc: rc6);
426 intel_wakeref_t wakeref;
427
428 with_intel_runtime_pm(uncore->rpm, wakeref)
429 rc6->bios_rc_state = intel_uncore_read(uncore, GEN6_RC_STATE);
430
431 rc6->bios_state_captured = true;
432 }
433
434 return rc6->bios_rc_state & RC_SW_TARGET_STATE_MASK;
435}
436
437static bool bxt_check_bios_rc6_setup(struct intel_rc6 *rc6)
438{
439 struct intel_uncore *uncore = rc6_to_uncore(rc: rc6);
440 struct drm_i915_private *i915 = rc6_to_i915(rc: rc6);
441 u32 rc6_ctx_base, rc_ctl, rc_sw_target;
442 bool enable_rc6 = true;
443
444 rc_ctl = intel_uncore_read(uncore, GEN6_RC_CONTROL);
445 rc_sw_target = intel_uncore_read(uncore, GEN6_RC_STATE);
446 rc_sw_target &= RC_SW_TARGET_STATE_MASK;
447 rc_sw_target >>= RC_SW_TARGET_STATE_SHIFT;
448 drm_dbg(&i915->drm, "BIOS enabled RC states: "
449 "HW_CTRL %s HW_RC6 %s SW_TARGET_STATE %x\n",
450 str_on_off(rc_ctl & GEN6_RC_CTL_HW_ENABLE),
451 str_on_off(rc_ctl & GEN6_RC_CTL_RC6_ENABLE),
452 rc_sw_target);
453
454 if (!(intel_uncore_read(uncore, RC6_LOCATION) & RC6_CTX_IN_DRAM)) {
455 drm_dbg(&i915->drm, "RC6 Base location not set properly.\n");
456 enable_rc6 = false;
457 }
458
459 /*
460 * The exact context size is not known for BXT, so assume a page size
461 * for this check.
462 */
463 rc6_ctx_base =
464 intel_uncore_read(uncore, RC6_CTX_BASE) & RC6_CTX_BASE_MASK;
465 if (!(rc6_ctx_base >= i915->dsm.reserved.start &&
466 rc6_ctx_base + PAGE_SIZE < i915->dsm.reserved.end)) {
467 drm_dbg(&i915->drm, "RC6 Base address not as expected.\n");
468 enable_rc6 = false;
469 }
470
471 if (!((intel_uncore_read(uncore, PWRCTX_MAXCNT(RENDER_RING_BASE)) & IDLE_TIME_MASK) > 1 &&
472 (intel_uncore_read(uncore, PWRCTX_MAXCNT(GEN6_BSD_RING_BASE)) & IDLE_TIME_MASK) > 1 &&
473 (intel_uncore_read(uncore, PWRCTX_MAXCNT(BLT_RING_BASE)) & IDLE_TIME_MASK) > 1 &&
474 (intel_uncore_read(uncore, PWRCTX_MAXCNT(VEBOX_RING_BASE)) & IDLE_TIME_MASK) > 1)) {
475 drm_dbg(&i915->drm,
476 "Engine Idle wait time not set properly.\n");
477 enable_rc6 = false;
478 }
479
480 if (!intel_uncore_read(uncore, GEN8_PUSHBUS_CONTROL) ||
481 !intel_uncore_read(uncore, GEN8_PUSHBUS_ENABLE) ||
482 !intel_uncore_read(uncore, GEN8_PUSHBUS_SHIFT)) {
483 drm_dbg(&i915->drm, "Pushbus not setup properly.\n");
484 enable_rc6 = false;
485 }
486
487 if (!intel_uncore_read(uncore, GEN6_GFXPAUSE)) {
488 drm_dbg(&i915->drm, "GFX pause not setup properly.\n");
489 enable_rc6 = false;
490 }
491
492 if (!intel_uncore_read(uncore, GEN8_MISC_CTRL0)) {
493 drm_dbg(&i915->drm, "GPM control not setup properly.\n");
494 enable_rc6 = false;
495 }
496
497 return enable_rc6;
498}
499
500static bool rc6_supported(struct intel_rc6 *rc6)
501{
502 struct drm_i915_private *i915 = rc6_to_i915(rc: rc6);
503 struct intel_gt *gt = rc6_to_gt(rc6);
504
505 if (!HAS_RC6(i915))
506 return false;
507
508 if (intel_vgpu_active(i915))
509 return false;
510
511 if (is_mock_gt(gt: rc6_to_gt(rc6)))
512 return false;
513
514 if (IS_GEN9_LP(i915) && !bxt_check_bios_rc6_setup(rc6)) {
515 drm_notice(&i915->drm,
516 "RC6 and powersaving disabled by BIOS\n");
517 return false;
518 }
519
520 if (IS_METEORLAKE(gt->i915) &&
521 !intel_check_bios_c6_setup(rc6)) {
522 drm_notice(&i915->drm,
523 "C6 disabled by BIOS\n");
524 return false;
525 }
526
527 if (IS_MEDIA_GT_IP_STEP(gt, IP_VER(13, 0), STEP_A0, STEP_B0)) {
528 drm_notice(&i915->drm,
529 "Media RC6 disabled on A step\n");
530 return false;
531 }
532
533 return true;
534}
535
536static void rpm_get(struct intel_rc6 *rc6)
537{
538 GEM_BUG_ON(rc6->wakeref);
539 pm_runtime_get_sync(dev: rc6_to_i915(rc: rc6)->drm.dev);
540 rc6->wakeref = true;
541}
542
543static void rpm_put(struct intel_rc6 *rc6)
544{
545 GEM_BUG_ON(!rc6->wakeref);
546 pm_runtime_put(dev: rc6_to_i915(rc: rc6)->drm.dev);
547 rc6->wakeref = false;
548}
549
550static bool pctx_corrupted(struct intel_rc6 *rc6)
551{
552 struct drm_i915_private *i915 = rc6_to_i915(rc: rc6);
553
554 if (!NEEDS_RC6_CTX_CORRUPTION_WA(i915))
555 return false;
556
557 if (intel_uncore_read(uncore: rc6_to_uncore(rc: rc6), GEN8_RC6_CTX_INFO))
558 return false;
559
560 drm_notice(&i915->drm,
561 "RC6 context corruption, disabling runtime power management\n");
562 return true;
563}
564
565static void __intel_rc6_disable(struct intel_rc6 *rc6)
566{
567 struct drm_i915_private *i915 = rc6_to_i915(rc: rc6);
568 struct intel_uncore *uncore = rc6_to_uncore(rc: rc6);
569 struct intel_gt *gt = rc6_to_gt(rc6);
570
571 /* Take control of RC6 back from GuC */
572 intel_guc_rc_disable(guc: &gt->uc.guc);
573
574 intel_uncore_forcewake_get(uncore, domains: FORCEWAKE_ALL);
575 if (GRAPHICS_VER(i915) >= 9)
576 intel_uncore_write_fw(uncore, GEN9_PG_ENABLE, 0);
577 intel_uncore_write_fw(uncore, GEN6_RC_CONTROL, 0);
578 intel_uncore_write_fw(uncore, GEN6_RC_STATE, 0);
579 intel_uncore_forcewake_put(uncore, domains: FORCEWAKE_ALL);
580}
581
582static void rc6_res_reg_init(struct intel_rc6 *rc6)
583{
584 i915_reg_t res_reg[INTEL_RC6_RES_MAX] = {
585 [0 ... INTEL_RC6_RES_MAX - 1] = INVALID_MMIO_REG,
586 };
587
588 switch (rc6_to_gt(rc6)->type) {
589 case GT_MEDIA:
590 res_reg[INTEL_RC6_RES_RC6] = MTL_MEDIA_MC6;
591 break;
592 default:
593 res_reg[INTEL_RC6_RES_RC6_LOCKED] = GEN6_GT_GFX_RC6_LOCKED;
594 res_reg[INTEL_RC6_RES_RC6] = GEN6_GT_GFX_RC6;
595 res_reg[INTEL_RC6_RES_RC6p] = GEN6_GT_GFX_RC6p;
596 res_reg[INTEL_RC6_RES_RC6pp] = GEN6_GT_GFX_RC6pp;
597 break;
598 }
599
600 memcpy(rc6->res_reg, res_reg, sizeof(res_reg));
601}
602
603void intel_rc6_init(struct intel_rc6 *rc6)
604{
605 struct drm_i915_private *i915 = rc6_to_i915(rc: rc6);
606 int err;
607
608 /* Disable runtime-pm until we can save the GPU state with rc6 pctx */
609 rpm_get(rc6);
610
611 if (!rc6_supported(rc6))
612 return;
613
614 rc6_res_reg_init(rc6);
615
616 if (IS_CHERRYVIEW(i915))
617 err = chv_rc6_init(rc6);
618 else if (IS_VALLEYVIEW(i915))
619 err = vlv_rc6_init(rc6);
620 else
621 err = 0;
622
623 /* Sanitize rc6, ensure it is disabled before we are ready. */
624 __intel_rc6_disable(rc6);
625
626 rc6->supported = err == 0;
627}
628
629void intel_rc6_sanitize(struct intel_rc6 *rc6)
630{
631 memset(rc6->prev_hw_residency, 0, sizeof(rc6->prev_hw_residency));
632
633 if (rc6->enabled) { /* unbalanced suspend/resume */
634 rpm_get(rc6);
635 rc6->enabled = false;
636 }
637
638 if (rc6->supported)
639 __intel_rc6_disable(rc6);
640}
641
642void intel_rc6_enable(struct intel_rc6 *rc6)
643{
644 struct drm_i915_private *i915 = rc6_to_i915(rc: rc6);
645 struct intel_uncore *uncore = rc6_to_uncore(rc: rc6);
646
647 if (!rc6->supported)
648 return;
649
650 GEM_BUG_ON(rc6->enabled);
651
652 intel_uncore_forcewake_get(uncore, domains: FORCEWAKE_ALL);
653
654 if (IS_CHERRYVIEW(i915))
655 chv_rc6_enable(rc6);
656 else if (IS_VALLEYVIEW(i915))
657 vlv_rc6_enable(rc6);
658 else if (GRAPHICS_VER(i915) >= 11)
659 gen11_rc6_enable(rc6);
660 else if (GRAPHICS_VER(i915) >= 9)
661 gen9_rc6_enable(rc6);
662 else if (IS_BROADWELL(i915))
663 gen8_rc6_enable(rc6);
664 else if (GRAPHICS_VER(i915) >= 6)
665 gen6_rc6_enable(rc6);
666
667 rc6->manual = rc6->ctl_enable & GEN6_RC_CTL_RC6_ENABLE;
668 if (NEEDS_RC6_CTX_CORRUPTION_WA(i915))
669 rc6->ctl_enable = 0;
670
671 intel_uncore_forcewake_put(uncore, domains: FORCEWAKE_ALL);
672
673 if (unlikely(pctx_corrupted(rc6)))
674 return;
675
676 /* rc6 is ready, runtime-pm is go! */
677 rpm_put(rc6);
678 rc6->enabled = true;
679}
680
681void intel_rc6_unpark(struct intel_rc6 *rc6)
682{
683 struct intel_uncore *uncore = rc6_to_uncore(rc: rc6);
684
685 if (!rc6->enabled)
686 return;
687
688 /* Restore HW timers for automatic RC6 entry while busy */
689 intel_uncore_write_fw(uncore, GEN6_RC_CONTROL, rc6->ctl_enable);
690}
691
692void intel_rc6_park(struct intel_rc6 *rc6)
693{
694 struct intel_uncore *uncore = rc6_to_uncore(rc: rc6);
695 unsigned int target;
696
697 if (!rc6->enabled)
698 return;
699
700 if (unlikely(pctx_corrupted(rc6))) {
701 intel_rc6_disable(rc6);
702 return;
703 }
704
705 if (!rc6->manual)
706 return;
707
708 /* Turn off the HW timers and go directly to rc6 */
709 intel_uncore_write_fw(uncore, GEN6_RC_CONTROL, GEN6_RC_CTL_RC6_ENABLE);
710
711 if (HAS_RC6pp(rc6_to_i915(rc6)))
712 target = 0x6; /* deepest rc6 */
713 else if (HAS_RC6p(rc6_to_i915(rc6)))
714 target = 0x5; /* deep rc6 */
715 else
716 target = 0x4; /* normal rc6 */
717 intel_uncore_write_fw(uncore, GEN6_RC_STATE, target << RC_SW_TARGET_STATE_SHIFT);
718}
719
720void intel_rc6_disable(struct intel_rc6 *rc6)
721{
722 if (!rc6->enabled)
723 return;
724
725 rpm_get(rc6);
726 rc6->enabled = false;
727
728 __intel_rc6_disable(rc6);
729}
730
731void intel_rc6_fini(struct intel_rc6 *rc6)
732{
733 struct drm_i915_gem_object *pctx;
734 struct intel_uncore *uncore = rc6_to_uncore(rc: rc6);
735
736 intel_rc6_disable(rc6);
737
738 /* We want the BIOS C6 state preserved across loads for MTL */
739 if (IS_METEORLAKE(rc6_to_i915(rc6)) && rc6->bios_state_captured)
740 intel_uncore_write_fw(uncore, GEN6_RC_STATE, rc6->bios_rc_state);
741
742 pctx = fetch_and_zero(&rc6->pctx);
743 if (pctx)
744 i915_gem_object_put(obj: pctx);
745
746 if (rc6->wakeref)
747 rpm_put(rc6);
748}
749
750static u64 vlv_residency_raw(struct intel_uncore *uncore, const i915_reg_t reg)
751{
752 u32 lower, upper, tmp;
753 int loop = 2;
754
755 /*
756 * The register accessed do not need forcewake. We borrow
757 * uncore lock to prevent concurrent access to range reg.
758 */
759 lockdep_assert_held(&uncore->lock);
760
761 /*
762 * vlv and chv residency counters are 40 bits in width.
763 * With a control bit, we can choose between upper or lower
764 * 32bit window into this counter.
765 *
766 * Although we always use the counter in high-range mode elsewhere,
767 * userspace may attempt to read the value before rc6 is initialised,
768 * before we have set the default VLV_COUNTER_CONTROL value. So always
769 * set the high bit to be safe.
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 do {
775 tmp = upper;
776
777 intel_uncore_write_fw(uncore, VLV_COUNTER_CONTROL,
778 _MASKED_BIT_DISABLE(VLV_COUNT_RANGE_HIGH));
779 lower = intel_uncore_read_fw(uncore, reg);
780
781 intel_uncore_write_fw(uncore, VLV_COUNTER_CONTROL,
782 _MASKED_BIT_ENABLE(VLV_COUNT_RANGE_HIGH));
783 upper = intel_uncore_read_fw(uncore, reg);
784 } while (upper != tmp && --loop);
785
786 /*
787 * Everywhere else we always use VLV_COUNTER_CONTROL with the
788 * VLV_COUNT_RANGE_HIGH bit set - so it is safe to leave it set
789 * now.
790 */
791
792 return lower | (u64)upper << 8;
793}
794
795u64 intel_rc6_residency_ns(struct intel_rc6 *rc6, enum intel_rc6_res_type id)
796{
797 struct drm_i915_private *i915 = rc6_to_i915(rc: rc6);
798 struct intel_uncore *uncore = rc6_to_uncore(rc: rc6);
799 u64 time_hw, prev_hw, overflow_hw;
800 i915_reg_t reg = rc6->res_reg[id];
801 unsigned int fw_domains;
802 unsigned long flags;
803 u32 mul, div;
804
805 if (!rc6->supported)
806 return 0;
807
808 fw_domains = intel_uncore_forcewake_for_reg(uncore, reg, FW_REG_READ);
809
810 spin_lock_irqsave(&uncore->lock, flags);
811 intel_uncore_forcewake_get__locked(uncore, domains: fw_domains);
812
813 /* On VLV and CHV, residency time is in CZ units rather than 1.28us */
814 if (IS_VALLEYVIEW(i915) || IS_CHERRYVIEW(i915)) {
815 mul = 1000000;
816 div = i915->czclk_freq;
817 overflow_hw = BIT_ULL(40);
818 time_hw = vlv_residency_raw(uncore, reg);
819 } else {
820 /* 833.33ns units on Gen9LP, 1.28us elsewhere. */
821 if (IS_GEN9_LP(i915)) {
822 mul = 10000;
823 div = 12;
824 } else {
825 mul = 1280;
826 div = 1;
827 }
828
829 overflow_hw = BIT_ULL(32);
830 time_hw = intel_uncore_read_fw(uncore, reg);
831 }
832
833 /*
834 * Counter wrap handling.
835 *
836 * Store previous hw counter values for counter wrap-around handling. But
837 * relying on a sufficient frequency of queries otherwise counters can still wrap.
838 */
839 prev_hw = rc6->prev_hw_residency[id];
840 rc6->prev_hw_residency[id] = time_hw;
841
842 /* RC6 delta from last sample. */
843 if (time_hw >= prev_hw)
844 time_hw -= prev_hw;
845 else
846 time_hw += overflow_hw - prev_hw;
847
848 /* Add delta to RC6 extended raw driver copy. */
849 time_hw += rc6->cur_residency[id];
850 rc6->cur_residency[id] = time_hw;
851
852 intel_uncore_forcewake_put__locked(uncore, domains: fw_domains);
853 spin_unlock_irqrestore(lock: &uncore->lock, flags);
854
855 return mul_u64_u32_div(a: time_hw, mul, div);
856}
857
858u64 intel_rc6_residency_us(struct intel_rc6 *rc6, enum intel_rc6_res_type id)
859{
860 return DIV_ROUND_UP_ULL(intel_rc6_residency_ns(rc6, id), 1000);
861}
862
863void intel_rc6_print_residency(struct seq_file *m, const char *title,
864 enum intel_rc6_res_type id)
865{
866 struct intel_gt *gt = m->private;
867 i915_reg_t reg = gt->rc6.res_reg[id];
868 intel_wakeref_t wakeref;
869
870 with_intel_runtime_pm(gt->uncore->rpm, wakeref)
871 seq_printf(m, fmt: "%s %u (%llu us)\n", title,
872 intel_uncore_read(uncore: gt->uncore, reg),
873 intel_rc6_residency_us(rc6: &gt->rc6, id));
874}
875
876#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
877#include "selftest_rc6.c"
878#endif
879

source code of linux/drivers/gpu/drm/i915/gt/intel_rc6.c