drm/i915/display: Allow users to disable PSR2

Some users are suffering with PSR2 issues that are under debug or
issues that were root caused to panel firmware bugs, to make life of
those users easier here adding a option to disable PSR2 with kernel
parameters so they can still benefit from PSR1 power savings.

Using the same enable_psr that is current used to turn the whole
feature on or off and allowing user to select up to what PSR version
it should enable.
Right now users only set this parameter to 0 when they want to disable
PSR1 and PSR2 or don't add it at all leaving it to per-chip behavior
so it should not cause a bad impact on users.

v2:
- changing enable_psr values (Ville and Rodrigo)

Link: https://gitlab.freedesktop.org/drm/intel/-/issues/4951
Cc: Jouni Högander <jouni.hogander@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Reviewed-by: Jouni Högander <jouni.hogander@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220224202523.993560-1-jose.souza@intel.com

diff --git a/drivers/gpu/drm/i915/display/intel_psr.c b/drivers/gpu/drm/i915/display/intel_psr.c
index b6b7bb5be5ae1fb554222b8307cbf57cae65a045..bbd581ed08159045f96f6e89eeef17e729b5b446 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_psr.c
+++ b/drivers/gpu/drm/i915/display/intel_psr.c
@@ -100,11 +100,15 @@ static bool psr_global_enabled(struct intel_dp *intel_dp)
 
 static bool psr2_global_enabled(struct intel_dp *intel_dp)
 {
+       struct drm_i915_private *i915 = dp_to_i915(intel_dp);
+
        switch (intel_dp->psr.debug & I915_PSR_DEBUG_MODE_MASK) {
        case I915_PSR_DEBUG_DISABLE:
        case I915_PSR_DEBUG_FORCE_PSR1:
                return false;
        default:
+               if (i915->params.enable_psr == 1)
+                       return false;
                return true;
        }
 }

diff --git a/drivers/gpu/drm/i915/i915_params.c b/drivers/gpu/drm/i915/i915_params.c
index a28b10bc20ade23ba5d863d1a360ef11108ccfe2..1930487e5f09b142a4ab9081ada70a69c89d5022 100644 (file)
--- a/drivers/gpu/drm/i915/i915_params.c
+++ b/drivers/gpu/drm/i915/i915_params.c
@@ -96,7 +96,7 @@ i915_param_named_unsafe(enable_hangcheck, bool, 0400,
 
 i915_param_named_unsafe(enable_psr, int, 0400,
        "Enable PSR "
-       "(0=disabled, 1=enabled) "
+       "(0=disabled, 1=enable up to PSR1, 2=enable up to PSR2) "
        "Default: -1 (use per-chip default)");
 
 i915_param_named(psr_safest_params, bool, 0400,