From: Imre Deak <imre.deak@intel.com>

Date: Thu, 20 Jul 2017 14:28:20 +0300

Subject: [PATCH] drm/i915: Fix scaler init during CRTC HW state readout

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References: bnc#1060662

Patch-mainline: v4.12.5

Git-commit: 283d6860d64f5091565bf729b0a6d6af14ae6c27

Git-commit: 5fb9dadf336f3590c799e8cbde348215dccc2aa2

commit 283d6860d64f5091565bf729b0a6d6af14ae6c27 upstream.

The scaler allocation code depends on a non-zero default value for the

crtc scaler_id, so make sure we initialize the scaler state accordingly

even if the crtc is off. This fixes at least an initial YUV420 modeset

(added in a follow-up patchset by Shashank) when booting with the screen

off: after the initial HW readout and modeset which enables the scaler a

subsequent modeset will disable the scaler which isn't properly

allocated. This results in a funky HW state where the pipe scaler HW

registers can't be modified and the normally black screen is grey and

shifted to the right or jitters.

The problem was revealed by Shashank's YUV420 patchset and first

reported by Ville.

v2:

- In the stable tag also include versions which need backporting (Jani)

Cc: Jani Nikula <jani.nikula@intel.com>

Cc: Shashank Sharma <shashank.sharma@intel.com>

Cc: Ville Syrj채l채 <ville.syrjala@linux.intel.com>

Cc: Chandra Konduru <chandra.konduru@intel.com>

Cc: Matt Roper <matthew.d.roper@intel.com>

Reported-by: Ville Syrj채l채 <ville.syrjala@linux.intel.com>

Fixes: a1b2278e4dfc ("drm/i915: skylake panel fitting using shared scalers")

Signed-off-by: Imre Deak <imre.deak@intel.com>

Reviewed-by: Mahesh Kumar <mahesh1.kumar@intel.com>

Link: https://patchwork.freedesktop.org/patch/msgid/20170720112820.26816-1-imre.deak@intel.com

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

(cherry picked from commit 5fb9dadf336f3590c799e8cbde348215dccc2aa2)

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Signed-off-by: Jiri Slaby <jslaby@suse.cz>

---

 drivers/gpu/drm/i915/intel_display.c | 14 +++++++-------

 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c

index 9106ea32b048..881df8843e66 100644

--- a/drivers/gpu/drm/i915/intel_display.c

+++ b/drivers/gpu/drm/i915/intel_display.c

@@ -9085,6 +9085,13 @@ static bool haswell_get_pipe_config(struct intel_crtc *crtc,

 	u64 power_domain_mask;

 	bool active;

+	if (INTEL_GEN(dev_priv) >= 9) {

+		intel_crtc_init_scalers(crtc, pipe_config);

+

+		pipe_config->scaler_state.scaler_id = -1;

+		pipe_config->scaler_state.scaler_users &= ~(1 << SKL_CRTC_INDEX);

+	}

+

 	power_domain = POWER_DOMAIN_PIPE(crtc->pipe);

 	if (!intel_display_power_get_if_enabled(dev_priv, power_domain))

 		return false;

@@ -9113,13 +9120,6 @@ static bool haswell_get_pipe_config(struct intel_crtc *crtc,

 	pipe_config->gamma_mode =

 		I915_READ(GAMMA_MODE(crtc->pipe)) & GAMMA_MODE_MODE_MASK;

-	if (INTEL_GEN(dev_priv) >= 9) {

-		intel_crtc_init_scalers(crtc, pipe_config);

-

-		pipe_config->scaler_state.scaler_id = -1;

-		pipe_config->scaler_state.scaler_users &= ~(1 << SKL_CRTC_INDEX);

-	}

-

 	power_domain = POWER_DOMAIN_PIPE_PANEL_FITTER(crtc->pipe);

 	if (intel_display_power_get_if_enabled(dev_priv, power_domain)) {

 		power_domain_mask |= BIT_ULL(power_domain);

-- 

2.14.2