On Fri, 17 Mar 2023 16:16:41 -0700, Umesh Nerlige Ramappa wrote: > Hi Umesh, Please read from bottom to top. Mostly nits but let's see what you think. > OAM does not work with media C6 enabled on some steppings of MTL. > Disable OAM if we detect that media C6 was enabled in bios. > > v2: (Ashutosh) > - Remove drm_notice from the driver load path > - Log a drm_err when opening an OAM stream on affected steppings > > Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@xxxxxxxxx> > --- > drivers/gpu/drm/i915/i915_perf.c | 41 ++++++++++++++++++++++++++++++++ > 1 file changed, 41 insertions(+) > > diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c > index 18afa76653b7..823379d63caf 100644 > --- a/drivers/gpu/drm/i915/i915_perf.c > +++ b/drivers/gpu/drm/i915/i915_perf.c > @@ -209,6 +209,7 @@ > #include "gt/intel_gt_regs.h" > #include "gt/intel_lrc.h" > #include "gt/intel_lrc_reg.h" > +#include "gt/intel_rc6.h" > #include "gt/intel_ring.h" > #include "gt/uc/intel_guc_slpc.h" > > @@ -4216,6 +4217,20 @@ static int read_properties_unlocked(struct i915_perf *perf, > return -EINVAL; > } > > + /* > + * Wa_14017512683: mtl[a0..c0): Use of OAM must be preceded with Media > + * C6 disable in BIOS. Fail if Media C6 is enabled on steppings where OAM > + * does not work as expected. > + */ > + if (IS_MTL_MEDIA_STEP(props->engine->i915, STEP_A0, STEP_C0) && > + props->engine->gt->type == GT_MEDIA && Instead of gt type I think it's better to check perf_group->type. That is why as I said below maybe better to have a valid perf_group even in this case. > + intel_check_bios_c6_setup(&props->engine->gt->rc6)) { > + drm_dbg(&perf->i915->drm, > + "OAM requires media C6 to be disabled in BIOS\n"); > + return -EINVAL; > + } So now we can change this check to something like: if (engine->perf_group->type == OAM && i915_perf->mtl_bios_mc6_enabled) > + > + > if (!engine_supports_oa(props->engine)) { > drm_dbg(&perf->i915->drm, > "Engine not supported by OA %d:%d\n", > @@ -4897,6 +4912,15 @@ static u32 num_perf_groups_per_gt(struct intel_gt *gt) > > static u32 __oam_engine_group(struct intel_engine_cs *engine) > { > + /* > + * Wa_14017512683: mtl[a0..c0): Use of OAM must be preceded with Media > + * C6 disable in BIOS. To disable use of OAM with media engines, set the > + * oa_group to PERF_GROUP_INVALID. > + */ > + if (IS_MTL_MEDIA_STEP(engine->i915, STEP_A0, STEP_C0) && > + intel_check_bios_c6_setup(&engine->gt->rc6)) > + return PERF_GROUP_INVALID; I think we should just remove this. Let the perf group be valid in this case too since we cannot support OA for a different reason. Then we can use the OAM perf group above. Though if we drop this we have only 2 instances of the checks instead of 3 so maybe ok to not have i915_perf->mtl_bios_mc6_enabled? > + > if (GRAPHICS_VER_FULL(engine->i915) >= IP_VER(12, 70)) { > /* > * There's 1 SAMEDIA gt and 1 OAM per SAMEDIA gt. All media slices > @@ -5316,6 +5340,23 @@ int i915_perf_ioctl_version(struct drm_i915_private *i915) > * > * 7: Add support for video decode and enhancement classes. > */ > + > + /* > + * Wa_14017512683: mtl[a0..c0): Use of OAM must be preceded with Media > + * C6 disable in BIOS. If Media C6 is enabled in BIOS, return version 6 > + * to indicate that OA media is not supported. > + */ > + if (IS_MTL_MEDIA_STEP(i915, STEP_A0, STEP_C0)) { > + struct intel_gt *gt; > + int i; > + > + for_each_gt(gt, i915, i) { > + if (gt->type == GT_MEDIA && > + intel_check_bios_c6_setup(>->rc6)) Rather than repeat this comment and these checks (MTL stepping and intel_check_bios_c6_setup) 3 times, I think it will be simpler to set a variable (say i915_perf->mtl_bios_mc6_enabled) in i915_perf_init() and reuse that in the 3 places. > + return 6; > + } > + } > + > return 7; > } Thanks. -- Ashutosh