1// SPDX-License-Identifier: MIT
2/*
3 * Copyright © 2019 Intel Corporation
4 */
5
6#include "intel_context.h"
7#include "intel_engine_pm.h"
8#include "intel_gpu_commands.h"
9#include "intel_gt_requests.h"
10#include "intel_ring.h"
11#include "selftest_rc6.h"
12
13#include "selftests/i915_random.h"
14#include "selftests/librapl.h"
15
16static u64 rc6_residency(struct intel_rc6 *rc6)
17{
18 u64 result;
19
20 /* XXX VLV_GT_MEDIA_RC6? */
21
22 result = intel_rc6_residency_ns(rc6, id: INTEL_RC6_RES_RC6);
23 if (HAS_RC6p(rc6_to_i915(rc6)))
24 result += intel_rc6_residency_ns(rc6, id: INTEL_RC6_RES_RC6p);
25 if (HAS_RC6pp(rc6_to_i915(rc6)))
26 result += intel_rc6_residency_ns(rc6, id: INTEL_RC6_RES_RC6pp);
27
28 return result;
29}
30
31int live_rc6_manual(void *arg)
32{
33 struct intel_gt *gt = arg;
34 struct intel_rc6 *rc6 = &gt->rc6;
35 u64 rc0_power, rc6_power;
36 intel_wakeref_t wakeref;
37 bool has_power;
38 ktime_t dt;
39 u64 res[2];
40 int err = 0;
41
42 /*
43 * Our claim is that we can "encourage" the GPU to enter rc6 at will.
44 * Let's try it!
45 */
46
47 if (!rc6->enabled)
48 return 0;
49
50 /* bsw/byt use a PCU and decouple RC6 from our manual control */
51 if (IS_VALLEYVIEW(gt->i915) || IS_CHERRYVIEW(gt->i915))
52 return 0;
53
54 has_power = librapl_supported(i915: gt->i915);
55 wakeref = intel_runtime_pm_get(rpm: gt->uncore->rpm);
56
57 /* Force RC6 off for starters */
58 __intel_rc6_disable(rc6);
59 msleep(msecs: 1); /* wakeup is not immediate, takes about 100us on icl */
60
61 res[0] = rc6_residency(rc6);
62
63 dt = ktime_get();
64 rc0_power = librapl_energy_uJ();
65 msleep(msecs: 1000);
66 rc0_power = librapl_energy_uJ() - rc0_power;
67 dt = ktime_sub(ktime_get(), dt);
68 res[1] = rc6_residency(rc6);
69 if ((res[1] - res[0]) >> 10) {
70 pr_err("RC6 residency increased by %lldus while disabled for 1000ms!\n",
71 (res[1] - res[0]) >> 10);
72 err = -EINVAL;
73 goto out_unlock;
74 }
75
76 if (has_power) {
77 rc0_power = div64_u64(NSEC_PER_SEC * rc0_power,
78 divisor: ktime_to_ns(kt: dt));
79 if (!rc0_power) {
80 pr_err("No power measured while in RC0\n");
81 err = -EINVAL;
82 goto out_unlock;
83 }
84 }
85
86 /* Manually enter RC6 */
87 intel_rc6_park(rc6);
88
89 res[0] = rc6_residency(rc6);
90 intel_uncore_forcewake_flush(uncore: rc6_to_uncore(rc: rc6), fw_domains: FORCEWAKE_ALL);
91 dt = ktime_get();
92 rc6_power = librapl_energy_uJ();
93 msleep(msecs: 100);
94 rc6_power = librapl_energy_uJ() - rc6_power;
95 dt = ktime_sub(ktime_get(), dt);
96 res[1] = rc6_residency(rc6);
97 if (res[1] == res[0]) {
98 pr_err("Did not enter RC6! RC6_STATE=%08x, RC6_CONTROL=%08x, residency=%lld\n",
99 intel_uncore_read_fw(gt->uncore, GEN6_RC_STATE),
100 intel_uncore_read_fw(gt->uncore, GEN6_RC_CONTROL),
101 res[0]);
102 err = -EINVAL;
103 }
104
105 if (has_power) {
106 rc6_power = div64_u64(NSEC_PER_SEC * rc6_power,
107 divisor: ktime_to_ns(kt: dt));
108 pr_info("GPU consumed %llduW in RC0 and %llduW in RC6\n",
109 rc0_power, rc6_power);
110 if (2 * rc6_power > rc0_power) {
111 pr_err("GPU leaked energy while in RC6!\n");
112 err = -EINVAL;
113 goto out_unlock;
114 }
115 }
116
117 /* Restore what should have been the original state! */
118 intel_rc6_unpark(rc6);
119
120out_unlock:
121 intel_runtime_pm_put(rpm: gt->uncore->rpm, wref: wakeref);
122 return err;
123}
124
125static const u32 *__live_rc6_ctx(struct intel_context *ce)
126{
127 struct i915_request *rq;
128 const u32 *result;
129 u32 cmd;
130 u32 *cs;
131
132 rq = intel_context_create_request(ce);
133 if (IS_ERR(ptr: rq))
134 return ERR_CAST(ptr: rq);
135
136 cs = intel_ring_begin(rq, num_dwords: 4);
137 if (IS_ERR(ptr: cs)) {
138 i915_request_add(rq);
139 return cs;
140 }
141
142 cmd = MI_STORE_REGISTER_MEM | MI_USE_GGTT;
143 if (GRAPHICS_VER(rq->i915) >= 8)
144 cmd++;
145
146 *cs++ = cmd;
147 *cs++ = i915_mmio_reg_offset(GEN8_RC6_CTX_INFO);
148 *cs++ = ce->timeline->hwsp_offset + 8;
149 *cs++ = 0;
150 intel_ring_advance(rq, cs);
151
152 result = rq->hwsp_seqno + 2;
153 i915_request_add(rq);
154
155 return result;
156}
157
158static struct intel_engine_cs **
159randomised_engines(struct intel_gt *gt,
160 struct rnd_state *prng,
161 unsigned int *count)
162{
163 struct intel_engine_cs *engine, **engines;
164 enum intel_engine_id id;
165 int n;
166
167 n = 0;
168 for_each_engine(engine, gt, id)
169 n++;
170 if (!n)
171 return NULL;
172
173 engines = kmalloc_array(n, size: sizeof(*engines), GFP_KERNEL);
174 if (!engines)
175 return NULL;
176
177 n = 0;
178 for_each_engine(engine, gt, id)
179 engines[n++] = engine;
180
181 i915_prandom_shuffle(arr: engines, elsz: sizeof(*engines), count: n, state: prng);
182
183 *count = n;
184 return engines;
185}
186
187int live_rc6_ctx_wa(void *arg)
188{
189 struct intel_gt *gt = arg;
190 struct intel_engine_cs **engines;
191 unsigned int n, count;
192 I915_RND_STATE(prng);
193 int err = 0;
194
195 /* A read of CTX_INFO upsets rc6. Poke the bear! */
196 if (GRAPHICS_VER(gt->i915) < 8)
197 return 0;
198
199 engines = randomised_engines(gt, prng: &prng, count: &count);
200 if (!engines)
201 return 0;
202
203 for (n = 0; n < count; n++) {
204 struct intel_engine_cs *engine = engines[n];
205 int pass;
206
207 for (pass = 0; pass < 2; pass++) {
208 struct i915_gpu_error *error = &gt->i915->gpu_error;
209 struct intel_context *ce;
210 unsigned int resets =
211 i915_reset_engine_count(error, engine);
212 const u32 *res;
213
214 /* Use a sacrifical context */
215 ce = intel_context_create(engine);
216 if (IS_ERR(ptr: ce)) {
217 err = PTR_ERR(ptr: ce);
218 goto out;
219 }
220
221 intel_engine_pm_get(engine);
222 res = __live_rc6_ctx(ce);
223 intel_engine_pm_put(engine);
224 intel_context_put(ce);
225 if (IS_ERR(ptr: res)) {
226 err = PTR_ERR(ptr: res);
227 goto out;
228 }
229
230 if (intel_gt_wait_for_idle(gt, HZ / 5) == -ETIME) {
231 intel_gt_set_wedged(gt);
232 err = -ETIME;
233 goto out;
234 }
235
236 intel_gt_pm_wait_for_idle(gt);
237 pr_debug("%s: CTX_INFO=%0x\n",
238 engine->name, READ_ONCE(*res));
239
240 if (resets !=
241 i915_reset_engine_count(error, engine)) {
242 pr_err("%s: GPU reset required\n",
243 engine->name);
244 add_taint_for_CI(i915: gt->i915, TAINT_WARN);
245 err = -EIO;
246 goto out;
247 }
248 }
249 }
250
251out:
252 kfree(objp: engines);
253 return err;
254}
255

source code of linux/drivers/gpu/drm/i915/gt/selftest_rc6.c