drm/i915: don't enable FBC when pixel rate exceeds 95% on HSW/BDW
BSpec says we shouldn't enable FBC on HSW/BDW when the pipe pixel rate
exceeds 95% of the core display clock.
v2:
- HSW also needs the WA (Ville).
- Add the WA name (Ville).
- Use the current cdclk (Ville).
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index ffd4ab1..e5242c0 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -949,6 +949,7 @@
FBC_ROTATION, /* rotation is not supported */
FBC_IN_DBG_MASTER, /* kernel debugger is active */
FBC_BAD_STRIDE, /* stride is not supported */
+ FBC_PIXEL_RATE, /* pixel rate is too big */
} no_fbc_reason;
bool (*fbc_enabled)(struct drm_i915_private *dev_priv);
diff --git a/drivers/gpu/drm/i915/intel_fbc.c b/drivers/gpu/drm/i915/intel_fbc.c
index 69726a7..1c4536a 100644
--- a/drivers/gpu/drm/i915/intel_fbc.c
+++ b/drivers/gpu/drm/i915/intel_fbc.c
@@ -482,6 +482,8 @@
return "Kernel debugger is active";
case FBC_BAD_STRIDE:
return "framebuffer stride not supported";
+ case FBC_PIXEL_RATE:
+ return "pixel rate is too big";
default:
MISSING_CASE(reason);
return "unknown reason";
@@ -828,6 +830,14 @@
goto out_disable;
}
+ /* WaFbcExceedCdClockThreshold:hsw,bdw */
+ if ((IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv)) &&
+ ilk_pipe_pixel_rate(intel_crtc->config) >=
+ dev_priv->cdclk_freq * 95 / 100) {
+ set_no_fbc_reason(dev_priv, FBC_PIXEL_RATE);
+ goto out_disable;
+ }
+
if (intel_fbc_setup_cfb(dev_priv, obj->base.size,
drm_format_plane_cpp(fb->pixel_format, 0))) {
set_no_fbc_reason(dev_priv, FBC_STOLEN_TOO_SMALL);