[PATCH] drm/i915: Discard BIOS framebuffers too small to accommodate chosen mode
From: Chris Wilson
Date: Wed Apr 23 2014 - 03:39:48 EST
If the inherited BIOS framebuffer is smaller than the mode selected for
fbdev, then if we continue to use it then we cause display corruption as
we do not setup the panel fitter to upscale.
Regression from commit d978ef14456a38034f6c0e94a794129501f89200
Author: Jesse Barnes <jbarnes@xxxxxxxxxxxxxxxx>
Date: Fri Mar 7 08:57:51 2014 -0800
drm/i915: Wrap the preallocated BIOS framebuffer and preserve for KMS fbcon v12
v2: Add a debug message to track the discard of the BIOS fb.
Reported-by: Knut Petersen <Knut_Petersen@xxxxxxxxxxx>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=77767
Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
Cc: Jesse Barnes <jbarnes@xxxxxxxxxxxxxxxx>
Reviewed-by: Daniel Vetter <daniel.vetter@xxxxxxxx>
---
drivers/gpu/drm/i915/intel_fbdev.c | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/drivers/gpu/drm/i915/intel_fbdev.c b/drivers/gpu/drm/i915/intel_fbdev.c
index b16116db6c37..dbd3f7ce6354 100644
--- a/drivers/gpu/drm/i915/intel_fbdev.c
+++ b/drivers/gpu/drm/i915/intel_fbdev.c
@@ -133,6 +133,16 @@ static int intelfb_create(struct drm_fb_helper *helper,
mutex_lock(&dev->struct_mutex);
+ if (intel_fb &&
+ (sizes->fb_width > intel_fb->base.width ||
+ sizes->fb_height > intel_fb->base.height)) {
+ DRM_DEBUG_KMS("BIOS fb too small (%dx%d), we require (%dx%d),"
+ " releasing it\n",
+ intel_fb->base.width, intel_fb->base.height,
+ sizes->fb_width, sizes->fb_height);
+ drm_framebuffer_reference(&ifbdev->fb->base);
+ intel_fb = ifbdev->fb = NULL;
+ }
if (!intel_fb || WARN_ON(!intel_fb->obj)) {
DRM_DEBUG_KMS("no BIOS fb, allocating a new one\n");
ret = intelfb_alloc(helper, sizes);
--
1.9.2
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/