From: Vinay Belgaumkar vinay.belgaumkar@intel.com
[ Upstream commit 3e49de73fb89272dea01ba420c7ccbcf6b96aed7 ]
The scenario being fixed here is depicted in the following sequence-
modprobe i915 echo 1 > /sys/class/drm/card0/gt/gt0/slpc_ignore_eff_freq echo 300 > /sys/class/drm/card0/gt_min_freq_mhz (RPn) cat /sys/class/drm/card0/gt_cur_freq_mhz --> cur == RPn as expected echo 1 > /sys/kernel/debug/dri/0/gt0/reset --> reset cat /sys/class/drm/card0/gt_min_freq_mhz --> cached freq is RPn cat /sys/class/drm/card0/gt_cur_freq_mhz --> it's not RPn, but RPe!!
When SLPC reinitializes, it sets SLPC min freq to efficient frequency. Even if we disable efficient freq post that, we should restore the cached min freq (via H2G) for it to take effect.
v2: Clarify commit message (Ashutosh)
Fixes: 95ccf312a1e4 ("drm/i915/guc/slpc: Allow SLPC to use efficient frequency") Reviewed-by: Ashutosh Dixit ashutosh.dixit@intel.com Signed-off-by: Vinay Belgaumkar vinay.belgaumkar@intel.com Signed-off-by: Daniele Ceraolo Spurio daniele.ceraolospurio@intel.com Link: https://patchwork.freedesktop.org/patch/msgid/20230621014257.1769564-1-vinay... (cherry picked from commit da86b2b13f1d1ca26745b951ac94421f3137539a) Signed-off-by: Tvrtko Ursulin tvrtko.ursulin@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c index 56dbba1ef6684..cc18e8f664864 100644 --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_slpc.c @@ -606,7 +606,7 @@ static int slpc_set_softlimits(struct intel_guc_slpc *slpc) if (unlikely(ret)) return ret; slpc_to_gt(slpc)->defaults.min_freq = slpc->min_freq_softlimit; - } else if (slpc->min_freq_softlimit != slpc->min_freq) { + } else { return intel_guc_slpc_set_min_freq(slpc, slpc->min_freq_softlimit); }