[Intel-gfx] [PATCH] drm/i915/display: Allow users to disable PSR2

[José Roberto de Souza]

Some users are suffering with PSR2 issues that are under debug or
issues that were root caused to panel firmware, to make life of those
users easier here adding a option to disable PSR1 with kernel
parameter.

Using the same enable_psr that is current used to turn PSR1 and PSR2
off or on and adding a new value to only disable PSR2.
The previous valid values did not had their behavior changed.

Link: https://gitlab.freedesktop.org/drm/intel/-/issues/4951
Cc: Jouni Högander <jouni.hogander at intel.com>
Signed-off-by: José Roberto de Souza <jose.souza at intel.com>
---
 drivers/gpu/drm/i915/display/intel_psr.c | 4 ++++
 drivers/gpu/drm/i915/i915_params.c       | 2 +-
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/display/intel_psr.c b/drivers/gpu/drm/i915/display/intel_psr.c
index 2e0b092f4b6be..fc6b684bb7bec 100644
--- 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 == 2)
+			return false;
 		return true;
 	}
 }
diff --git a/drivers/gpu/drm/i915/i915_params.c b/drivers/gpu/drm/i915/i915_params.c
index eea355c2fc28a..a9b97e6eb3df0 100644
--- a/drivers/gpu/drm/i915/i915_params.c
+++ b/drivers/gpu/drm/i915/i915_params.c
@@ -94,7 +94,7 @@ 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 PSR2 if supported, 2=enable up to PSR1) "
 	"Default: -1 (use per-chip default)");
 
 i915_param_named(psr_safest_params, bool, 0400,
-- 
2.35.1