1 // SPDX-License-Identifier: MIT
2 /*
3 * Copyright © 2021 Intel Corporation
4 */
5
6 #define NUM_STEPS 5
7 #define H2G_DELAY 50000
8 #define delay_for_h2g() usleep_range(H2G_DELAY, H2G_DELAY + 10000)
9 #define FREQUENCY_REQ_UNIT DIV_ROUND_CLOSEST(GT_FREQUENCY_MULTIPLIER, \
10 GEN9_FREQ_SCALER)
11 enum test_type {
12 VARY_MIN,
13 VARY_MAX,
14 MAX_GRANTED,
15 SLPC_POWER,
16 TILE_INTERACTION,
17 };
18
19 struct slpc_thread {
20 struct kthread_worker *worker;
21 struct kthread_work work;
22 struct intel_gt *gt;
23 int result;
24 };
25
slpc_set_min_freq(struct intel_guc_slpc * slpc,u32 freq)26 static int slpc_set_min_freq(struct intel_guc_slpc *slpc, u32 freq)
27 {
28 int ret;
29
30 ret = intel_guc_slpc_set_min_freq(slpc, freq);
31 if (ret)
32 pr_err("Could not set min frequency to [%u]\n", freq);
33 else /* Delay to ensure h2g completes */
34 delay_for_h2g();
35
36 return ret;
37 }
38
slpc_set_max_freq(struct intel_guc_slpc * slpc,u32 freq)39 static int slpc_set_max_freq(struct intel_guc_slpc *slpc, u32 freq)
40 {
41 int ret;
42
43 ret = intel_guc_slpc_set_max_freq(slpc, freq);
44 if (ret)
45 pr_err("Could not set maximum frequency [%u]\n",
46 freq);
47 else /* Delay to ensure h2g completes */
48 delay_for_h2g();
49
50 return ret;
51 }
52
slpc_set_freq(struct intel_gt * gt,u32 freq)53 static int slpc_set_freq(struct intel_gt *gt, u32 freq)
54 {
55 int err;
56 struct intel_guc_slpc *slpc = >->uc.guc.slpc;
57
58 err = slpc_set_max_freq(slpc, freq);
59 if (err) {
60 pr_err("Unable to update max freq");
61 return err;
62 }
63
64 err = slpc_set_min_freq(slpc, freq);
65 if (err) {
66 pr_err("Unable to update min freq");
67 return err;
68 }
69
70 return err;
71 }
72
measure_power_at_freq(struct intel_gt * gt,int * freq,u64 * power)73 static u64 measure_power_at_freq(struct intel_gt *gt, int *freq, u64 *power)
74 {
75 int err = 0;
76
77 err = slpc_set_freq(gt, *freq);
78 if (err)
79 return err;
80 *freq = intel_rps_read_actual_frequency(>->rps);
81 *power = measure_power(>->rps, freq);
82
83 return err;
84 }
85
vary_max_freq(struct intel_guc_slpc * slpc,struct intel_rps * rps,u32 * max_act_freq)86 static int vary_max_freq(struct intel_guc_slpc *slpc, struct intel_rps *rps,
87 u32 *max_act_freq)
88 {
89 u32 step, max_freq, req_freq;
90 u32 act_freq;
91 int err = 0;
92
93 /* Go from max to min in 5 steps */
94 step = (slpc->rp0_freq - slpc->min_freq) / NUM_STEPS;
95 *max_act_freq = slpc->min_freq;
96 for (max_freq = slpc->rp0_freq; max_freq > slpc->min_freq;
97 max_freq -= step) {
98 err = slpc_set_max_freq(slpc, max_freq);
99 if (err)
100 break;
101
102 req_freq = intel_rps_read_punit_req_frequency(rps);
103
104 /* GuC requests freq in multiples of 50/3 MHz */
105 if (req_freq > (max_freq + FREQUENCY_REQ_UNIT)) {
106 pr_err("SWReq is %d, should be at most %d\n", req_freq,
107 max_freq + FREQUENCY_REQ_UNIT);
108 err = -EINVAL;
109 }
110
111 act_freq = intel_rps_read_actual_frequency(rps);
112 if (act_freq > *max_act_freq)
113 *max_act_freq = act_freq;
114
115 if (err)
116 break;
117 }
118
119 return err;
120 }
121
vary_min_freq(struct intel_guc_slpc * slpc,struct intel_rps * rps,u32 * max_act_freq)122 static int vary_min_freq(struct intel_guc_slpc *slpc, struct intel_rps *rps,
123 u32 *max_act_freq)
124 {
125 u32 step, min_freq, req_freq;
126 u32 act_freq;
127 int err = 0;
128
129 /* Go from min to max in 5 steps */
130 step = (slpc->rp0_freq - slpc->min_freq) / NUM_STEPS;
131 *max_act_freq = slpc->min_freq;
132 for (min_freq = slpc->min_freq; min_freq < slpc->rp0_freq;
133 min_freq += step) {
134 err = slpc_set_min_freq(slpc, min_freq);
135 if (err)
136 break;
137
138 req_freq = intel_rps_read_punit_req_frequency(rps);
139
140 /* GuC requests freq in multiples of 50/3 MHz */
141 if (req_freq < (min_freq - FREQUENCY_REQ_UNIT)) {
142 pr_err("SWReq is %d, should be at least %d\n", req_freq,
143 min_freq - FREQUENCY_REQ_UNIT);
144 err = -EINVAL;
145 }
146
147 act_freq = intel_rps_read_actual_frequency(rps);
148 if (act_freq > *max_act_freq)
149 *max_act_freq = act_freq;
150
151 if (err)
152 break;
153 }
154
155 return err;
156 }
157
slpc_power(struct intel_gt * gt,struct intel_engine_cs * engine)158 static int slpc_power(struct intel_gt *gt, struct intel_engine_cs *engine)
159 {
160 struct intel_guc_slpc *slpc = >->uc.guc.slpc;
161 struct {
162 u64 power;
163 int freq;
164 } min, max;
165 int err = 0;
166
167 /*
168 * Our fundamental assumption is that running at lower frequency
169 * actually saves power. Let's see if our RAPL measurement supports
170 * that theory.
171 */
172 if (!librapl_supported(gt->i915))
173 return 0;
174
175 min.freq = slpc->min_freq;
176 err = measure_power_at_freq(gt, &min.freq, &min.power);
177
178 if (err)
179 return err;
180
181 max.freq = slpc->rp0_freq;
182 err = measure_power_at_freq(gt, &max.freq, &max.power);
183
184 if (err)
185 return err;
186
187 pr_info("%s: min:%llumW @ %uMHz, max:%llumW @ %uMHz\n",
188 engine->name,
189 min.power, min.freq,
190 max.power, max.freq);
191
192 if (10 * min.freq >= 9 * max.freq) {
193 pr_notice("Could not control frequency, ran at [%uMHz, %uMhz]\n",
194 min.freq, max.freq);
195 }
196
197 if (11 * min.power > 10 * max.power) {
198 pr_err("%s: did not conserve power when setting lower frequency!\n",
199 engine->name);
200 err = -EINVAL;
201 }
202
203 /* Restore min/max frequencies */
204 slpc_set_max_freq(slpc, slpc->rp0_freq);
205 slpc_set_min_freq(slpc, slpc->min_freq);
206
207 return err;
208 }
209
max_granted_freq(struct intel_guc_slpc * slpc,struct intel_rps * rps,u32 * max_act_freq)210 static int max_granted_freq(struct intel_guc_slpc *slpc, struct intel_rps *rps, u32 *max_act_freq)
211 {
212 struct intel_gt *gt = rps_to_gt(rps);
213 u32 perf_limit_reasons;
214 int err = 0;
215
216 err = slpc_set_min_freq(slpc, slpc->rp0_freq);
217 if (err)
218 return err;
219
220 *max_act_freq = intel_rps_read_actual_frequency(rps);
221 if (*max_act_freq != slpc->rp0_freq) {
222 /* Check if there was some throttling by pcode */
223 perf_limit_reasons = intel_uncore_read(gt->uncore,
224 intel_gt_perf_limit_reasons_reg(gt));
225
226 /* If not, this is an error */
227 if (!(perf_limit_reasons & GT0_PERF_LIMIT_REASONS_MASK)) {
228 pr_err("Pcode did not grant max freq\n");
229 err = -EINVAL;
230 } else {
231 pr_info("Pcode throttled frequency 0x%x\n", perf_limit_reasons);
232 }
233 }
234
235 return err;
236 }
237
run_test(struct intel_gt * gt,int test_type)238 static int run_test(struct intel_gt *gt, int test_type)
239 {
240 struct intel_guc_slpc *slpc = >->uc.guc.slpc;
241 struct intel_rps *rps = >->rps;
242 struct intel_engine_cs *engine;
243 enum intel_engine_id id;
244 struct igt_spinner spin;
245 u32 slpc_min_freq, slpc_max_freq;
246 int err = 0;
247
248 if (!intel_uc_uses_guc_slpc(>->uc))
249 return 0;
250
251 if (slpc->min_freq == slpc->rp0_freq) {
252 pr_err("Min/Max are fused to the same value\n");
253 return -EINVAL;
254 }
255
256 if (igt_spinner_init(&spin, gt))
257 return -ENOMEM;
258
259 if (intel_guc_slpc_get_max_freq(slpc, &slpc_max_freq)) {
260 pr_err("Could not get SLPC max freq\n");
261 return -EIO;
262 }
263
264 if (intel_guc_slpc_get_min_freq(slpc, &slpc_min_freq)) {
265 pr_err("Could not get SLPC min freq\n");
266 return -EIO;
267 }
268
269 /*
270 * Set min frequency to RPn so that we can test the whole
271 * range of RPn-RP0. This also turns off efficient freq
272 * usage and makes results more predictable.
273 */
274 err = slpc_set_min_freq(slpc, slpc->min_freq);
275 if (err) {
276 pr_err("Unable to update min freq!");
277 return err;
278 }
279
280 intel_gt_pm_wait_for_idle(gt);
281 intel_gt_pm_get(gt);
282 for_each_engine(engine, gt, id) {
283 struct i915_request *rq;
284 u32 max_act_freq;
285
286 if (!intel_engine_can_store_dword(engine))
287 continue;
288
289 st_engine_heartbeat_disable(engine);
290
291 rq = igt_spinner_create_request(&spin,
292 engine->kernel_context,
293 MI_NOOP);
294 if (IS_ERR(rq)) {
295 err = PTR_ERR(rq);
296 st_engine_heartbeat_enable(engine);
297 break;
298 }
299
300 i915_request_add(rq);
301
302 if (!igt_wait_for_spinner(&spin, rq)) {
303 pr_err("%s: Spinner did not start\n",
304 engine->name);
305 igt_spinner_end(&spin);
306 st_engine_heartbeat_enable(engine);
307 intel_gt_set_wedged(engine->gt);
308 err = -EIO;
309 break;
310 }
311
312 switch (test_type) {
313 case VARY_MIN:
314 err = vary_min_freq(slpc, rps, &max_act_freq);
315 break;
316
317 case VARY_MAX:
318 err = vary_max_freq(slpc, rps, &max_act_freq);
319 break;
320
321 case MAX_GRANTED:
322 case TILE_INTERACTION:
323 /* Media engines have a different RP0 */
324 if (gt->type != GT_MEDIA && (engine->class == VIDEO_DECODE_CLASS ||
325 engine->class == VIDEO_ENHANCEMENT_CLASS)) {
326 igt_spinner_end(&spin);
327 st_engine_heartbeat_enable(engine);
328 err = 0;
329 continue;
330 }
331
332 err = max_granted_freq(slpc, rps, &max_act_freq);
333 break;
334
335 case SLPC_POWER:
336 err = slpc_power(gt, engine);
337 break;
338 }
339
340 if (test_type != SLPC_POWER) {
341 pr_info("Max actual frequency for %s was %d\n",
342 engine->name, max_act_freq);
343
344 /* Actual frequency should rise above min */
345 if (max_act_freq <= slpc->min_freq) {
346 pr_err("Actual freq did not rise above min\n");
347 pr_err("Perf Limit Reasons: 0x%x\n",
348 intel_uncore_read(gt->uncore,
349 intel_gt_perf_limit_reasons_reg(gt)));
350 err = -EINVAL;
351 }
352 }
353
354 igt_spinner_end(&spin);
355 st_engine_heartbeat_enable(engine);
356
357 if (err)
358 break;
359 }
360
361 /* Restore min/max frequencies */
362 slpc_set_max_freq(slpc, slpc_max_freq);
363 slpc_set_min_freq(slpc, slpc_min_freq);
364
365 if (igt_flush_test(gt->i915))
366 err = -EIO;
367
368 intel_gt_pm_put(gt);
369 igt_spinner_fini(&spin);
370 intel_gt_pm_wait_for_idle(gt);
371
372 return err;
373 }
374
live_slpc_vary_min(void * arg)375 static int live_slpc_vary_min(void *arg)
376 {
377 struct drm_i915_private *i915 = arg;
378 struct intel_gt *gt;
379 unsigned int i;
380 int ret;
381
382 for_each_gt(gt, i915, i) {
383 ret = run_test(gt, VARY_MIN);
384 if (ret)
385 return ret;
386 }
387
388 return ret;
389 }
390
live_slpc_vary_max(void * arg)391 static int live_slpc_vary_max(void *arg)
392 {
393 struct drm_i915_private *i915 = arg;
394 struct intel_gt *gt;
395 unsigned int i;
396 int ret;
397
398 for_each_gt(gt, i915, i) {
399 ret = run_test(gt, VARY_MAX);
400 if (ret)
401 return ret;
402 }
403
404 return ret;
405 }
406
407 /* check if pcode can grant RP0 */
live_slpc_max_granted(void * arg)408 static int live_slpc_max_granted(void *arg)
409 {
410 struct drm_i915_private *i915 = arg;
411 struct intel_gt *gt;
412 unsigned int i;
413 int ret;
414
415 for_each_gt(gt, i915, i) {
416 ret = run_test(gt, MAX_GRANTED);
417 if (ret)
418 return ret;
419 }
420
421 return ret;
422 }
423
live_slpc_power(void * arg)424 static int live_slpc_power(void *arg)
425 {
426 struct drm_i915_private *i915 = arg;
427 struct intel_gt *gt;
428 unsigned int i;
429 int ret;
430
431 for_each_gt(gt, i915, i) {
432 ret = run_test(gt, SLPC_POWER);
433 if (ret)
434 return ret;
435 }
436
437 return ret;
438 }
439
slpc_spinner_thread(struct kthread_work * work)440 static void slpc_spinner_thread(struct kthread_work *work)
441 {
442 struct slpc_thread *thread = container_of(work, typeof(*thread), work);
443
444 thread->result = run_test(thread->gt, TILE_INTERACTION);
445 }
446
live_slpc_tile_interaction(void * arg)447 static int live_slpc_tile_interaction(void *arg)
448 {
449 struct drm_i915_private *i915 = arg;
450 struct intel_gt *gt;
451 struct slpc_thread *threads;
452 int i = 0, ret = 0;
453
454 threads = kcalloc(I915_MAX_GT, sizeof(*threads), GFP_KERNEL);
455 if (!threads)
456 return -ENOMEM;
457
458 for_each_gt(gt, i915, i) {
459 threads[i].worker = kthread_create_worker(0, "igt/slpc_parallel:%d", gt->info.id);
460
461 if (IS_ERR(threads[i].worker)) {
462 ret = PTR_ERR(threads[i].worker);
463 break;
464 }
465
466 threads[i].gt = gt;
467 kthread_init_work(&threads[i].work, slpc_spinner_thread);
468 kthread_queue_work(threads[i].worker, &threads[i].work);
469 }
470
471 for_each_gt(gt, i915, i) {
472 int status;
473
474 if (IS_ERR_OR_NULL(threads[i].worker))
475 continue;
476
477 kthread_flush_work(&threads[i].work);
478 status = READ_ONCE(threads[i].result);
479 if (status && !ret) {
480 pr_err("%s GT %d failed ", __func__, gt->info.id);
481 ret = status;
482 }
483 kthread_destroy_worker(threads[i].worker);
484 }
485
486 kfree(threads);
487 return ret;
488 }
489
intel_slpc_live_selftests(struct drm_i915_private * i915)490 int intel_slpc_live_selftests(struct drm_i915_private *i915)
491 {
492 static const struct i915_subtest tests[] = {
493 SUBTEST(live_slpc_vary_max),
494 SUBTEST(live_slpc_vary_min),
495 SUBTEST(live_slpc_max_granted),
496 SUBTEST(live_slpc_power),
497 SUBTEST(live_slpc_tile_interaction),
498 };
499
500 struct intel_gt *gt;
501 unsigned int i;
502
503 for_each_gt(gt, i915, i) {
504 if (intel_gt_is_wedged(gt))
505 return 0;
506 }
507
508 return i915_live_subtests(tests, i915);
509 }
510