drm/i915: Do not read GAMMA_MODE register
Implement Daniel Stone's recommendation to not read registers to infer
the hardware's state.
v2: Read GAMMA_MODE register value at init (Matt Roper's comment)
v3: Read GAMMA_MODE register in intel_modeset_readout_hw_state along
with other registers (Matt Roper's comment).
v4: Mask GAMMA_MODE register with interesting bits when reading
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1458125837-2576-3-git-send-email-lionel.g.landwerlin@intel.com
diff --git a/drivers/gpu/drm/i915/intel_color.c b/drivers/gpu/drm/i915/intel_color.c
index 35b7f62..16657eb 100644
--- a/drivers/gpu/drm/i915/intel_color.c
+++ b/drivers/gpu/drm/i915/intel_color.c
@@ -121,6 +121,8 @@
struct drm_device *dev = crtc->dev;
struct drm_i915_private *dev_priv = dev->dev_private;
struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
+ struct intel_crtc_state *intel_crtc_state =
+ to_intel_crtc_state(crtc->state);
bool reenable_ips = false;
/*
@@ -128,11 +130,12 @@
* GAMMA_MODE is configured for split gamma and IPS_CTL has IPS enabled.
*/
if (IS_HASWELL(dev) && intel_crtc->config->ips_enabled &&
- ((I915_READ(GAMMA_MODE(intel_crtc->pipe)) & GAMMA_MODE_MODE_MASK) ==
- GAMMA_MODE_MODE_SPLIT)) {
+ (intel_crtc_state->gamma_mode == GAMMA_MODE_MODE_SPLIT)) {
hsw_disable_ips(intel_crtc);
reenable_ips = true;
}
+
+ intel_crtc_state->gamma_mode = GAMMA_MODE_MODE_8BIT;
I915_WRITE(GAMMA_MODE(intel_crtc->pipe), GAMMA_MODE_MODE_8BIT);
i9xx_load_luts(crtc);
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 4e0695d..a06c656 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -9961,6 +9961,9 @@
intel_get_pipe_src_size(crtc, pipe_config);
+ pipe_config->gamma_mode =
+ I915_READ(GAMMA_MODE(crtc->pipe)) & GAMMA_MODE_MODE_MASK;
+
if (INTEL_INFO(dev)->gen >= 9) {
skl_init_scalers(dev, crtc, pipe_config);
}
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 5d0da22..d4945bb 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -578,6 +578,9 @@
*/
bool need_postvbl_update;
} wm;
+
+ /* Gamma mode programmed on the pipe */
+ uint32_t gamma_mode;
};
struct vlv_wm_state {