drm/i915: Disable PSR in Apple panels

i915 yet don't support PSR in Apple panels, so lets keep it disabled
while we work on that.

v2: Renamed DP_DPCD_QUIRK_PSR_NOT_CURRENTLY_SUPPORTED to
DP_DPCD_QUIRK_NO_PSR (Ville)

v3:
Adding documentation to DP_DPCD_QUIRK_NO_PSR(Dhinakaran and Jani)
Fixed typo in comment of the new quirk entry(Jani)

Fixes: 598c6cfe06 (drm/i915/psr: Enable PSR1 on gen-9+ HW)
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20181204003403.23361-1-jose.souza@intel.com

drivers/gpu/drm/drm_dp_helper.c

@@ -1273,6 +1273,8 @@ static const struct dpcd_quirk dpcd_quirk_list[] = {
 	{ OUI(0x00, 0x22, 0xb9), DEVICE_ID_ANY, true, BIT(DP_DPCD_QUIRK_CONSTANT_N) },
 	/* LG LP140WF6-SPM1 eDP panel */
 	{ OUI(0x00, 0x22, 0xb9), DEVICE_ID('s', 'i', 'v', 'a', 'r', 'T'), false, BIT(DP_DPCD_QUIRK_CONSTANT_N) },
+	/* Apple panels need some additional handling to support PSR */
+	{ OUI(0x00, 0x10, 0xfa), DEVICE_ID_ANY, false, BIT(DP_DPCD_QUIRK_NO_PSR) }
 };
 
 #undef OUI

drivers/gpu/drm/i915/intel_psr.c

@@ -274,10 +274,16 @@ void intel_psr_init_dpcd(struct intel_dp *intel_dp)
 	DRM_DEBUG_KMS("eDP panel supports PSR version %x\n",
 		      intel_dp->psr_dpcd[0]);
 
+	if (drm_dp_has_quirk(&intel_dp->desc, DP_DPCD_QUIRK_NO_PSR)) {
+		DRM_DEBUG_KMS("PSR support not currently available for this panel\n");
+		return;
+	}
+
 	if (!(intel_dp->edp_dpcd[1] & DP_EDP_SET_POWER_CAP)) {
 		DRM_DEBUG_KMS("Panel lacks power state control, PSR cannot be enabled\n");
 		return;
 	}
+
 	dev_priv->psr.sink_support = true;
 	dev_priv->psr.sink_sync_latency =
 		intel_dp_get_sink_sync_latency(intel_dp);

include/drm/drm_dp_helper.h

@@ -1365,6 +1365,13 @@ enum drm_dp_quirk {
 	 * to 16 bits. So will give a constant value (0x8000) for compatability.
 	 */
 	DP_DPCD_QUIRK_CONSTANT_N,
+	/**
+	 * @DP_DPCD_QUIRK_NO_PSR
+	 *
+	 * The device does not support PSR even if reports that it supports or
+	 * driver still need to implement proper handling for such device.
+	 */
+	DP_DPCD_QUIRK_NO_PSR,
 };
 
 /**