Erratum SKL075: Display Flicker May Occur When Both VT-d And FBC Are Enabled
"Display flickering may occur when both FBC (Frame Buffer Compression)
and VT - d (Intel® Virtualization Technology for Directed I/O) are enabled
and in use by the display controller."
Signed-off-by: Chris Wilson <ch...@chris-wilson.co.uk>
Cc: Paulo Zanoni <paulo.r.zan...@intel.com>
---
drivers/gpu/drm/i915/intel_fbc.c | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)
diff --git a/drivers/gpu/drm/i915/intel_fbc.c b/drivers/gpu/drm/i915/intel_fbc.c
index fddba1eed5ad..e47785467220 100644
--- a/drivers/gpu/drm/i915/intel_fbc.c
+++ b/drivers/gpu/drm/i915/intel_fbc.c
@@ -1230,6 +1230,18 @@ void intel_fbc_init_pipe_state(struct drm_i915_private
*dev_priv)
dev_priv->fbc.visible_pipes_mask |= (1 << crtc->pipe);
}
+static bool need_vtd_wa(struct drm_i915_private *dev_priv)
+{
+#ifdef CONFIG_INTEL_IOMMU
+ if (!intel_iommu_gfx_mapped)
+ return false;
+
+ if (INTEL_GEN(dev_priv) == 9)
+ return true;
+#endif
+ return false;
+}
+
/**
* intel_fbc_init - Initialize FBC
* @dev_priv: the i915 device
@@ -1247,6 +1259,12 @@ void intel_fbc_init(struct drm_i915_private *dev_priv)
fbc->active = false;
fbc->work.scheduled = false;
+ if (need_vtd_wa(dev_priv)) {
+ struct intel_device_info *info =
+ (struct intel_device_info *)&dev_priv->info;
+ info->has_fbc = false;
+ }
+
if (!HAS_FBC(dev_priv)) {
fbc->no_fbc_reason = "unsupported by this chipset";
return;
--
2.8.1
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx
