• Gerd Hoffmann's avatar
    drm/qxl: get vga ioports · fbf0a7f4
    Gerd Hoffmann authored
    
    
    qxl has two modes: "native" (used by the drm driver) and "vga" (vga
    compatibility mode, typically used for boot display and firmware
    framebuffers).
    
    Accessing any vga ioport will switch the qxl device into vga mode.
    The qxl driver never does that, but other drivers accessing vga ports
    can trigger that too and therefore disturb qxl operation.  So aquire
    the legacy vga ioports from vgaarb to avoid that.
    
    Reproducer: Boot kvm guest with both qxl and i915 vgpu, with qxl being
    first in pci scan order.
    
    v2: Skip this for secondary qxl cards which don't have vga mode in the
        first place (Frediano).
    
    Cc: Frediano Ziglio <fziglio@redhat.com>
    Signed-off-by: default avatarGerd Hoffmann <kraxel@redhat.com>
    Reviewed-by: default avatarDave Airlie <airlied@redhat.com>
    Link: http://patchwork.freedesktop.org/patch/msgid/20190805105401.29874-1-kraxel@redhat.com
    fbf0a7f4
qxl_drv.c 7.93 KB