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, INTEL_RC6_RES_RC6);
23	if (HAS_RC6p(rc6_to_i915(rc6)))
24		result += intel_rc6_residency_ns(rc6, INTEL_RC6_RES_RC6p);
25	if (HAS_RC6pp(rc6_to_i915(rc6)))
26		result += intel_rc6_residency_ns(rc6, 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(gt->i915);
55	wakeref = intel_runtime_pm_get(gt->uncore->rpm);
56
57	/* Force RC6 off for starters */
58	__intel_rc6_disable(rc6);
59	msleep(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(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				      ktime_to_ns(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(rc6_to_uncore(rc6), FORCEWAKE_ALL);
91	dt = ktime_get();
92	rc6_power = librapl_energy_uJ();
93	msleep(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				      ktime_to_ns(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(gt->uncore->rpm, 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(rq))
134		return ERR_CAST(rq);
135
136	cs = intel_ring_begin(rq, 4);
137	if (IS_ERR(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, 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(engines, sizeof(*engines), n, 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, &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(ce)) {
217				err = PTR_ERR(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(res)) {
226				err = PTR_ERR(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(gt->i915, TAINT_WARN);
245				err = -EIO;
246				goto out;
247			}
248		}
249	}
250
251out:
252	kfree(engines);
253	return err;
254}
255