Re: [Intel-gfx] [PATCH 14/15] drm/i915/guc/slpc: Add SLPC selftest

Matthew Brost
2021-07-27T19:17:01Z

On Mon, Jul 26, 2021 at 12:07:59PM -0700, Vinay Belgaumkar wrote:
> Tests that exercise the SLPC get/set frequency interfaces.
>
> Clamp_max will set max frequency to multiple levels and check
> that SLPC requests frequency lower than or equal to it.
>
> Clamp_min will set min frequency to different levels and check
> if SLPC requests are higher or equal to those levels.
>
> v2: Address review comments (Michal W)
> v3: Checkpatch() corrections
>
> Signed-off-by: Vinay Belgaumkar <vinay.belgaumkar@intel.com>
> ---
> drivers/gpu/drm/i915/gt/intel_rps.c | 1 +
> drivers/gpu/drm/i915/gt/selftest_slpc.c | 311 ++++++++++++++++++
> drivers/gpu/drm/i915/gt/selftest_slpc.h | 12 +
> .../drm/i915/selftests/i915_live_selftests.h | 1 +
> 4 files changed, 325 insertions(+)
> create mode 100644 drivers/gpu/drm/i915/gt/selftest_slpc.c
> create mode 100644 drivers/gpu/drm/i915/gt/selftest_slpc.h
>
> diff --git a/drivers/gpu/drm/i915/gt/intel_rps.c b/drivers/gpu/drm/i915/gt/intel_rps.c
> index 48d4147165a9..6237332835fe 100644
> --- a/drivers/gpu/drm/i915/gt/intel_rps.c
> +++ b/drivers/gpu/drm/i915/gt/intel_rps.c
> @@ -2318,4 +2318,5 @@ EXPORT_SYMBOL_GPL(i915_gpu_turbo_disable);
>
> #if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
> #include "selftest_rps.c"
> +#include "selftest_slpc.c"
> #endif
> diff --git a/drivers/gpu/drm/i915/gt/selftest_slpc.c b/drivers/gpu/drm/i915/gt/selftest_slpc.c
> new file mode 100644
> index 000000000000..5018f686686f
> --- /dev/null
> +++ b/drivers/gpu/drm/i915/gt/selftest_slpc.c
> @@ -0,0 +1,311 @@
> +// SPDX-License-Identifier: MIT
> +/*
> + * Copyright © 2021 Intel Corporation
> + */
> +
> +#include "selftest_slpc.h"
> +
> +#define NUM_STEPS 5
> +#define H2G_DELAY 50000
> +#define delay_for_h2g() usleep_range(H2G_DELAY, H2G_DELAY + 10000)
> +
> +static int set_min_freq(struct intel_guc_slpc *slpc, u32 freq)
> +{
> + int ret;
> +
> + ret = intel_guc_slpc_set_min_freq(slpc, freq);
> + if (ret)
> + pr_err("Could not set min frequency to [%u]\n", freq);
> + else /* Delay to ensure h2g completes */
> + delay_for_h2g();
> +
> + return ret;
> +}
> +
> +static int set_max_freq(struct intel_guc_slpc *slpc, u32 freq)
> +{
> + int ret;
> +
> + ret = intel_guc_slpc_set_max_freq(slpc, freq);
> + if (ret)
> + pr_err("Could not set maximum frequency [%u]\n",
> + freq);
> + else /* Delay to ensure h2g completes */
> + delay_for_h2g();
> +
> + return ret;
> +}
> +
> +int live_slpc_clamp_min(void *arg)
> +{
> + struct drm_i915_private *i915 = arg;
> + struct intel_gt *gt = &i915->gt;
> + struct intel_guc_slpc *slpc = &gt->uc.guc.slpc;
> + struct intel_rps *rps = &gt->rps;
> + struct intel_engine_cs *engine;
> + enum intel_engine_id id;
> + struct igt_spinner spin;
> + u32 slpc_min_freq, slpc_max_freq;
> + int err = 0;
> +
> + if (!intel_uc_uses_guc_slpc(&gt->uc))
> + return 0;
> +
> + if (igt_spinner_init(&spin, gt))
> + return -ENOMEM;
> +
> + if (intel_guc_slpc_get_max_freq(slpc, &slpc_max_freq)) {
> + pr_err("Could not get SLPC max freq\n");
> + return -EIO;
> + }
> +
> + if (intel_guc_slpc_get_min_freq(slpc, &slpc_min_freq)) {
> + pr_err("Could not get SLPC min freq\n");
> + return -EIO;
> + }
> +
> + if (slpc_min_freq == slpc_max_freq) {
> + pr_err("Min/Max are fused to the same value\n");
> + return -EINVAL;
> + }
> +
> + intel_gt_pm_wait_for_idle(gt);
> + intel_gt_pm_get(gt);
> + for_each_engine(engine, gt, id) {
> + struct i915_request *rq;
> + u32 step, min_freq, req_freq;
> + u32 act_freq, max_act_freq;
> +
> + if (!intel_engine_can_store_dword(engine))
> + continue;
> +
> + /* Go from min to max in 5 steps */
> + step = (slpc_max_freq - slpc_min_freq) / NUM_STEPS;
> + max_act_freq = slpc_min_freq;
> + for (min_freq = slpc_min_freq; min_freq < slpc_max_freq;
> + min_freq += step) {
> + err = set_min_freq(slpc, min_freq);
> + if (err)
> + break;
> +
> + st_engine_heartbeat_disable(engine);
> +
> + rq = igt_spinner_create_request(&spin,
> + engine->kernel_context,
> + MI_NOOP);
> + if (IS_ERR(rq)) {
> + err = PTR_ERR(rq);
> + st_engine_heartbeat_enable(engine);
> + break;
> + }
> +
> + i915_request_add(rq);
> +
> + if (!igt_wait_for_spinner(&spin, rq)) {
> + pr_err("%s: Spinner did not start\n",
> + engine->name);
> + igt_spinner_end(&spin);
> + st_engine_heartbeat_enable(engine);
> + intel_gt_set_wedged(engine->gt);
> + err = -EIO;
> + break;
> + }
> +
> + /* Wait for GuC to detect business and raise
> + * requested frequency if necessary.
> + */
> + delay_for_h2g();
> +
> + req_freq = intel_rps_read_punit_req_frequency(rps);
> +
> + /* GuC requests freq in multiples of 50/3 MHz */
> + if (req_freq < (min_freq - 50/3)) {
> + pr_err("SWReq is %d, should be at least %d\n", req_freq,
> + min_freq - 50/3);
> + igt_spinner_end(&spin);
> + st_engine_heartbeat_enable(engine);
> + err = -EINVAL;
> + break;
> + }
> +
> + act_freq = intel_rps_read_actual_frequency(rps);
> + if (act_freq > max_act_freq)
> + max_act_freq = act_freq;
> +
> + igt_spinner_end(&spin);
> + st_engine_heartbeat_enable(engine);
> + }
> +
> + pr_info("Max actual frequency for %s was %d\n",
> + engine->name, max_act_freq);
> +
> + /* Actual frequency should rise above min */
> + if (max_act_freq == slpc_min_freq) {
> + pr_err("Actual freq did not rise above min\n");
> + err = -EINVAL;
> + }
> +
> + if (err)
> + break;
> + }
> +
> + /* Restore min/max frequencies */
> + set_max_freq(slpc, slpc_max_freq);
> + set_min_freq(slpc, slpc_min_freq);
> +
> + if (igt_flush_test(gt->i915))
> + err = -EIO;
> +
> + intel_gt_pm_put(gt);
> + igt_spinner_fini(&spin);
> + intel_gt_pm_wait_for_idle(gt);
> +
> + return err;
> +}
> +
> +int live_slpc_clamp_max(void *arg)
> +{

This test is really similar to live_slpc_clamp_min, have you tried to
combine these into a single function with arguments?

> + struct drm_i915_private *i915 = arg;
> + struct intel_gt *gt = &i915->gt;
> + struct intel_guc_slpc *slpc;
> + struct intel_rps *rps;
> + struct intel_engine_cs *engine;
> + enum intel_engine_id id;
> + struct igt_spinner spin;
> + int err = 0;
> + u32 slpc_min_freq, slpc_max_freq;
> +
> + slpc = &gt->uc.guc.slpc;
> + rps = &gt->rps;
> +
> + if (!intel_uc_uses_guc_slpc(&gt->uc))
> + return 0;
> +
> + if (igt_spinner_init(&spin, gt))
> + return -ENOMEM;
> +
> + if (intel_guc_slpc_get_max_freq(slpc, &slpc_max_freq)) {
> + pr_err("Could not get SLPC max freq\n");
> + return -EIO;
> + }
> +
> + if (intel_guc_slpc_get_min_freq(slpc, &slpc_min_freq)) {
> + pr_err("Could not get SLPC min freq\n");
> + return -EIO;
> + }
> +
> + if (slpc_min_freq == slpc_max_freq) {
> + pr_err("Min/Max are fused to the same value\n");
> + return -EINVAL;
> + }
> +
> + intel_gt_pm_wait_for_idle(gt);
> + intel_gt_pm_get(gt);
> + for_each_engine(engine, gt, id) {
> + struct i915_request *rq;
> + u32 max_freq, req_freq;
> + u32 act_freq, max_act_freq;
> + u32 step;
> +
> + if (!intel_engine_can_store_dword(engine))
> + continue;
> +
> + /* Go from max to min in 5 steps */
> + step = (slpc_max_freq - slpc_min_freq) / NUM_STEPS;
> + max_act_freq = slpc_min_freq;
> + for (max_freq = slpc_max_freq; max_freq > slpc_min_freq;
> + max_freq -= step) {
> + err = set_max_freq(slpc, max_freq);
> + if (err)
> + break;
> +
> + st_engine_heartbeat_disable(engine);
> +
> + rq = igt_spinner_create_request(&spin,
> + engine->kernel_context,
> + MI_NOOP);
> + if (IS_ERR(rq)) {
> + st_engine_heartbeat_enable(engine);
> + err = PTR_ERR(rq);
> + break;
> + }
> +
> + i915_request_add(rq);
> +
> + if (!igt_wait_for_spinner(&spin, rq)) {
> + pr_err("%s: SLPC spinner did not start\n",
> + engine->name);
> + igt_spinner_end(&spin);
> + st_engine_heartbeat_enable(engine);
> + intel_gt_set_wedged(engine->gt);
> + err = -EIO;
> + break;
> + }
> +
> + delay_for_h2g();
> +
> + /* Verify that SWREQ indeed was set to specific value */
> + req_freq = intel_rps_read_punit_req_frequency(rps);
> +
> + /* GuC requests freq in multiples of 50/3 MHz */
> + if (req_freq > (max_freq + 50/3)) {
> + pr_err("SWReq is %d, should be at most %d\n", req_freq,
> + max_freq + 50/3);
> + igt_spinner_end(&spin);
> + st_engine_heartbeat_enable(engine);
> + err = -EINVAL;
> + break;
> + }
> +
> + act_freq = intel_rps_read_actual_frequency(rps);
> + if (act_freq > max_act_freq)
> + max_act_freq = act_freq;
> +
> + st_engine_heartbeat_enable(engine);
> + igt_spinner_end(&spin);
> +
> + if (err)
> + break;
> + }
> +
> + pr_info("Max actual frequency for %s was %d\n",
> + engine->name, max_act_freq);
> +
> + /* Actual frequency should rise above min */
> + if (max_act_freq == slpc_min_freq) {
> + pr_err("Actual freq did not rise above min\n");
> + err = -EINVAL;
> + }
> +
> + if (igt_flush_test(gt->i915)) {
> + err = -EIO;
> + break;
> + }
> +
> + if (err)
> + break;
> + }
> +
> + /* Restore min/max freq */
> + set_max_freq(slpc, slpc_max_freq);
> + set_min_freq(slpc, slpc_min_freq);
> +
> + intel_gt_pm_put(gt);
> + igt_spinner_fini(&spin);
> + intel_gt_pm_wait_for_idle(gt);
> +
> + return err;
> +}
> +
> +int intel_slpc_live_selftests(struct drm_i915_private *i915)
> +{
> + static const struct i915_subtest tests[] = {
> + SUBTEST(live_slpc_clamp_max),
> + SUBTEST(live_slpc_clamp_min),
> + };
> +
> + if (intel_gt_is_wedged(&i915->gt))
> + return 0;
> +
> + return i915_live_subtests(tests, i915);
> +}
> diff --git a/drivers/gpu/drm/i915/gt/selftest_slpc.h b/drivers/gpu/drm/i915/gt/selftest_slpc.h
> new file mode 100644

I don't think you need this header as selftest_slpc.c is the only user
and you need to forward decl these functions. Even if you did, you could
just forward decl these in the C file.

Matt

> index 000000000000..0480e62ed3d7
> --- /dev/null
> +++ b/drivers/gpu/drm/i915/gt/selftest_slpc.h
> @@ -0,0 +1,12 @@
> +/* SPDX-License-Identifier: MIT */
> +/*
> + * Copyright © 2021 Intel Corporation
> + */
> +
> +#ifndef SELFTEST_SLPC_H
> +#define SELFTEST_SLPC_H
> +
> +int live_slpc_clamp_max(void *arg);
> +int live_slpc_clamp_min(void *arg);
> +
> +#endif /* SELFTEST_SLPC_H */
> diff --git a/drivers/gpu/drm/i915/selftests/i915_live_selftests.h b/drivers/gpu/drm/i915/selftests/i915_live_selftests.h
> index e2fd1b61af71..1746a56dda06 100644
> --- a/drivers/gpu/drm/i915/selftests/i915_live_selftests.h
> +++ b/drivers/gpu/drm/i915/selftests/i915_live_selftests.h
> @@ -47,5 +47,6 @@ selftest(hangcheck, intel_hangcheck_live_selftests)
> selftest(execlists, intel_execlists_live_selftests)
> selftest(ring_submission, intel_ring_submission_live_selftests)
> selftest(perf, i915_perf_live_selftests)
> +selftest(slpc, intel_slpc_live_selftests)
> /* Here be dragons: keep last to run last! */
> selftest(late_gt_pm, intel_gt_pm_late_selftests)
> --
> 2.25.0