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@xxxxxxxxxxxxxxxxxx> Cc: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> --- drivers/gpu/drm/i915/intel_display.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 7db292c469af..d9b91a585dbf 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -11341,6 +11341,9 @@ 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 -- 1.8.5.1 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
