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| author | Chris Wilson <chris@chris-wilson.co.uk> | 2014-02-07 18:37:03 -0200 |
|---|---|---|
| committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2014-02-12 18:52:56 +0100 |
| commit | c0cc8a556680afbfc6dc5033bdf9c8d2b85088e2 (patch) | |
| tree | 6ddaad6df7b4d031ae960727edf6f1a34b1c0ff1 /drivers | |
| parent | 75fa041de7d520007cdf519fed5c208f5ffffdf4 (diff) | |
| download | blackbird-op-linux-c0cc8a556680afbfc6dc5033bdf9c8d2b85088e2.tar.gz blackbird-op-linux-c0cc8a556680afbfc6dc5033bdf9c8d2b85088e2.zip | |
drm/i915: Short-circuit no-op vga_set_state()
Touching the VGA registers risks a hard machine hang, at least on this
ivb machine after removing a conflicting efifb. This is more than likely
related to the discovery that VGA IO decode on the more recent PCH
platforms is terminally broken.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/gpu/drm/i915/intel_display.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index cc426e10d746..1b2faa44764b 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -11513,6 +11513,9 @@ int intel_modeset_vga_set_state(struct drm_device *dev, bool state) return -EIO; } + if (!!(gmch_ctrl & INTEL_GMCH_VGA_DISABLE) == !state) + return 0; + if (state) gmch_ctrl &= ~INTEL_GMCH_VGA_DISABLE; else |
