From 6dc0d028f53945ca8de3e61a149f103f100d42df Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Mon, 27 Apr 2020 16:45:54 +0100 Subject: [PATCH] drm/i915/gt: Fix up clock frequency The bspec lists both the clock frequency and the effective interval. The interval corresponds to observed behaviour, so adjust the frequency to match. v2: Mika rightfully asked if we could measure the clock frequency from a selftest. Signed-off-by: Chris Wilson Cc: Mika Kuoppala Acked-by: Mika Kuoppala Link: https://patchwork.freedesktop.org/patch/msgid/20200427154554.12736-1-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/gt/intel_gt_clock_utils.c | 12 +-- drivers/gpu/drm/i915/gt/selftest_gt_pm.c | 1 + drivers/gpu/drm/i915/gt/selftest_rps.c | 139 +++++++++++++++++++++++++ drivers/gpu/drm/i915/gt/selftest_rps.h | 1 + 4 files changed, 147 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/i915/gt/intel_gt_clock_utils.c b/drivers/gpu/drm/i915/gt/intel_gt_clock_utils.c index 852a7d7..9990796 100644 --- a/drivers/gpu/drm/i915/gt/intel_gt_clock_utils.c +++ b/drivers/gpu/drm/i915/gt/intel_gt_clock_utils.c @@ -7,9 +7,9 @@ #include "intel_gt.h" #include "intel_gt_clock_utils.h" +#define MHZ_12 12000000 /* 12MHz (24MHz/2), 83.333ns */ +#define MHZ_12_5 12500000 /* 12.5MHz (25MHz/2), 80ns */ #define MHZ_19_2 19200000 /* 19.2MHz, 52.083ns */ -#define MHZ_24 24000000 /* 24MHz, 83.333ns */ -#define MHZ_25 25000000 /* 25MHz, 80ns */ static u32 read_clock_frequency(const struct intel_gt *gt) { @@ -21,19 +21,19 @@ static u32 read_clock_frequency(const struct intel_gt *gt) config >>= GEN11_RPM_CONFIG0_CRYSTAL_CLOCK_FREQ_SHIFT; switch (config) { - case 0: return MHZ_24; + case 0: return MHZ_12; case 1: case 2: return MHZ_19_2; default: - case 3: return MHZ_25; + case 3: return MHZ_12_5; } } else if (INTEL_GEN(gt->i915) >= 9) { if (IS_GEN9_LP(gt->i915)) return MHZ_19_2; else - return MHZ_24; + return MHZ_12; } else { - return MHZ_25; + return MHZ_12_5; } } diff --git a/drivers/gpu/drm/i915/gt/selftest_gt_pm.c b/drivers/gpu/drm/i915/gt/selftest_gt_pm.c index e02fdec..242181a 100644 --- a/drivers/gpu/drm/i915/gt/selftest_gt_pm.c +++ b/drivers/gpu/drm/i915/gt/selftest_gt_pm.c @@ -53,6 +53,7 @@ int intel_gt_pm_live_selftests(struct drm_i915_private *i915) { static const struct i915_subtest tests[] = { SUBTEST(live_rc6_manual), + SUBTEST(live_rps_clock_interval), SUBTEST(live_rps_control), SUBTEST(live_rps_frequency_cs), SUBTEST(live_rps_frequency_srm), diff --git a/drivers/gpu/drm/i915/gt/selftest_rps.c b/drivers/gpu/drm/i915/gt/selftest_rps.c index e13cbcb..181b29f 100644 --- a/drivers/gpu/drm/i915/gt/selftest_rps.c +++ b/drivers/gpu/drm/i915/gt/selftest_rps.c @@ -208,6 +208,145 @@ static void show_pstate_limits(struct intel_rps *rps) } } +int live_rps_clock_interval(void *arg) +{ + struct intel_gt *gt = arg; + struct intel_rps *rps = >->rps; + void (*saved_work)(struct work_struct *wrk); + struct intel_engine_cs *engine; + enum intel_engine_id id; + struct igt_spinner spin; + int err = 0; + + if (!rps->enabled) + return 0; + + if (igt_spinner_init(&spin, gt)) + return -ENOMEM; + + intel_gt_pm_wait_for_idle(gt); + saved_work = rps->work.func; + rps->work.func = dummy_rps_work; + + intel_gt_pm_get(gt); + intel_rps_disable(>->rps); + + intel_gt_check_clock_frequency(gt); + + for_each_engine(engine, gt, id) { + unsigned long saved_heartbeat; + struct i915_request *rq; + ktime_t dt; + u32 cycles; + + if (!intel_engine_can_store_dword(engine)) + continue; + + saved_heartbeat = engine_heartbeat_disable(engine); + + rq = igt_spinner_create_request(&spin, + engine->kernel_context, + MI_NOOP); + if (IS_ERR(rq)) { + engine_heartbeat_enable(engine, saved_heartbeat); + err = PTR_ERR(rq); + break; + } + + i915_request_add(rq); + + if (!igt_wait_for_spinner(&spin, rq)) { + pr_err("%s: RPS spinner did not start\n", + engine->name); + igt_spinner_end(&spin); + engine_heartbeat_enable(engine, saved_heartbeat); + intel_gt_set_wedged(engine->gt); + err = -EIO; + break; + } + + intel_uncore_forcewake_get(gt->uncore, FORCEWAKE_ALL); + + intel_uncore_write_fw(gt->uncore, GEN6_RP_CUR_UP_EI, 0); + + /* Set the evaluation interval to infinity! */ + intel_uncore_write_fw(gt->uncore, + GEN6_RP_UP_EI, 0xffffffff); + intel_uncore_write_fw(gt->uncore, + GEN6_RP_UP_THRESHOLD, 0xffffffff); + + intel_uncore_write_fw(gt->uncore, GEN6_RP_CONTROL, + GEN6_RP_ENABLE | GEN6_RP_UP_BUSY_AVG); + + if (wait_for(intel_uncore_read_fw(gt->uncore, + GEN6_RP_CUR_UP_EI), + 10)) { + /* Just skip the test; assume lack of HW support */ + pr_notice("%s: rps evalution interval not ticking\n", + engine->name); + err = -ENODEV; + } else { + preempt_disable(); + dt = ktime_get(); + cycles = -intel_uncore_read_fw(gt->uncore, + GEN6_RP_CUR_UP_EI); + udelay(1000); + dt = ktime_sub(ktime_get(), dt); + cycles += intel_uncore_read_fw(gt->uncore, + GEN6_RP_CUR_UP_EI); + preempt_enable(); + } + + intel_uncore_write_fw(gt->uncore, GEN6_RP_CONTROL, 0); + intel_uncore_forcewake_put(gt->uncore, FORCEWAKE_ALL); + + igt_spinner_end(&spin); + engine_heartbeat_enable(engine, saved_heartbeat); + + if (err == 0) { + u64 time = intel_gt_pm_interval_to_ns(gt, cycles); + u32 expected = + intel_gt_ns_to_pm_interval(gt, ktime_to_ns(dt)); + + pr_info("%s: rps counted %d C0 cycles [%lldns] in %lldns [%d cycles], using GT clock frequency of %uKHz\n", + engine->name, cycles, time, ktime_to_ns(dt), expected, + gt->clock_frequency / 1000); + + if (10 * time < 9 * ktime_to_ns(dt) || + 10 * time > 11 * ktime_to_ns(dt)) { + pr_err("%s: rps clock time does not match walltime!\n", + engine->name); + err = -EINVAL; + } + + if (10 * expected < 9 * cycles || + 10 * expected > 11 * cycles) { + pr_err("%s: walltime does not match rps clock ticks!\n", + engine->name); + err = -EINVAL; + } + } + + if (igt_flush_test(gt->i915)) + err = -EIO; + + break; /* once is enough */ + } + + intel_rps_enable(>->rps); + intel_gt_pm_put(gt); + + igt_spinner_fini(&spin); + + intel_gt_pm_wait_for_idle(gt); + rps->work.func = saved_work; + + if (err == -ENODEV) /* skipped, don't report a fail */ + err = 0; + + return err; +} + int live_rps_control(void *arg) { struct intel_gt *gt = arg; diff --git a/drivers/gpu/drm/i915/gt/selftest_rps.h b/drivers/gpu/drm/i915/gt/selftest_rps.h index 76c4b19..6e82a63 100644 --- a/drivers/gpu/drm/i915/gt/selftest_rps.h +++ b/drivers/gpu/drm/i915/gt/selftest_rps.h @@ -7,6 +7,7 @@ #define SELFTEST_RPS_H int live_rps_control(void *arg); +int live_rps_clock_interval(void *arg); int live_rps_frequency_cs(void *arg); int live_rps_frequency_srm(void *arg); int live_rps_power(void *arg); -- 2.7.4