[Intel-gfx] [PATCH] drm/i915: Disable FBC if BIOS reserved memory (stolen) is unavailable

[Chris Wilson]

The FBC requires a couple of contiguous buffers, which we allocate from
stolen memory. If stolen memory is unavailable, we cannot allocate those
buffers and so cannot support FBC. Mark it so.

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/display/intel_fbc.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/i915/display/intel_fbc.c b/drivers/gpu/drm/i915/display/intel_fbc.c
index dc34b23e2320..3111ecaeabd0 100644
--- a/drivers/gpu/drm/i915/display/intel_fbc.c
+++ b/drivers/gpu/drm/i915/display/intel_fbc.c
@@ -1320,6 +1320,9 @@ void intel_fbc_init(struct drm_i915_private *dev_priv)
 	fbc->enabled = false;
 	fbc->active = false;
 
+	if (!drm_mm_initialized(&dev_priv->mm.stolen))
+		mkwrite_device_info(dev_priv)->display.has_fbc = false;
+
 	if (need_fbc_vtd_wa(dev_priv))
 		mkwrite_device_info(dev_priv)->display.has_fbc = false;
 
-- 
2.23.0