[Intel-gfx] [PATCH v2] drm/i915/psr: Enable PSR1 on gen-9+ HW

[Dhinakaran Pandiyan]

We have new tests and fixes in place since the feature was last
disabled. Try again for gen-9+ hardware and enable only PSR1 by default as
a first step.
v2: Remove typo fix and comment improvements (Rodrigo)

Cc: Jani Nikula <jani.nikula at intel.com>
Cc: Jose Roberto de Souza <jose.souza at intel.com>
Cc: Paulo Zanoni <paulo.r.zanoni at intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
References: commit 2ee7dc497e34 ("drm/i915: disable PSR by default on HSW/BDW")
References: commit dcb2e993f3c0 ("Revert "drm/i915: Enable PSR by default on Valleyview and Cherryview."")
Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan at intel.com>
---
 drivers/gpu/drm/i915/intel_psr.c | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_psr.c b/drivers/gpu/drm/i915/intel_psr.c
index b6838b525502..5a2660ad8203 100644
--- a/drivers/gpu/drm/i915/intel_psr.c
+++ b/drivers/gpu/drm/i915/intel_psr.c
@@ -71,6 +71,10 @@ static bool psr_global_enabled(u32 debug)
 static bool intel_psr2_enabled(struct drm_i915_private *dev_priv,
 			       const struct intel_crtc_state *crtc_state)
 {
+	/* Disable PSR2 by default for all platforms */
+	if (i915_modparams.enable_psr == -1)
+		return false;
+
 	switch (dev_priv->psr.debug & I915_PSR_DEBUG_MODE_MASK) {
 	case I915_PSR_DEBUG_FORCE_PSR1:
 		return false;
@@ -1065,12 +1069,9 @@ void intel_psr_init(struct drm_i915_private *dev_priv)
 	if (!dev_priv->psr.sink_support)
 		return;
 
-	if (i915_modparams.enable_psr == -1) {
-		i915_modparams.enable_psr = dev_priv->vbt.psr.enable;
-
-		/* Per platform default: all disabled. */
-		i915_modparams.enable_psr = 0;
-	}
+	if (i915_modparams.enable_psr == -1)
+		if (INTEL_GEN(dev_priv) < 9 || !dev_priv->vbt.psr.enable)
+			i915_modparams.enable_psr = 0;
 
 	/* Set link_standby x link_off defaults */
 	if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv))
-- 
2.17.1