• Ville Syrjälä's avatar
    Revert "drm/i915: Preserve VGACNTR bits from the BIOS" · 01f5a626
    Ville Syrjälä authored
    The VGA_2X_MODE bit apparently affects the display even when the VGA
    plane is disabled. The bit will set by the BIOS when the panel width
    is at least 1280 pixels. So by preserving the bit from the BIOS we
    end up with corrupted display on machines with such high res panels.
    I only have 1024x768 panels on my gen2 machines so never ran into
    this problem.
    
    The original reason for preserving the VGACNTR register was to make
    my 830 survive S3 with acpi_sleep=s3_bios option. However after
    further 830 fixes that option is no longer needed to make S3 work
    and preserving VGACNTR doesn't seem to be necessary without it,
    so we can just revert the entire patch.
    
    This reverts
    commit 69769f9a
    Author: Ville Syrjälä <ville.syrjala@linux.intel.com>
    Date:   Fri Aug 15 01:22:08 2014 +0300
    
        drm/i915: Preserve VGACNTR bits from the BIOS
    
    Cc: Bruno Prémont <bonbons@linux-vserver.org>
    Cc: stable@vger.kernel.org
    Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=87171Signed-off-by: default avatarVille Syrjälä <ville.syrjala@linux.intel.com>
    Signed-off-by: default avatarJani Nikula <jani.nikula@intel.com>
    01f5a626
i915_drv.h 91.9 KB