• Helge Deller's avatar
    fbcon: Add option to enable legacy hardware acceleration · a3f781a9
    Helge Deller authored
    Add a config option CONFIG_FRAMEBUFFER_CONSOLE_LEGACY_ACCELERATION to
    enable bitblt and fillrect hardware acceleration in the framebuffer
    console. If disabled, such acceleration will not be used, even if it is
    supported by the graphics hardware driver.
    
    If you plan to use DRM as your main graphics output system, you should
    disable this option since it will prevent compiling in code which isn't
    used later on when DRM takes over.
    
    For all other configurations, e.g. if none of your graphic cards support
    DRM (yet), DRM isn't available for your architecture, or you can't be
    sure that the graphic card in the target system will support DRM, you
    most likely want to enable this option.
    
    In the non-accelerated case (e.g. when DRM is used), the inlined
    fb_scrollmode() function is hardcoded to return SCROLL_REDRAW and as such the
    compiler is able to optimize much unneccesary code away.
    
    In this v3 patch version I additionally changed the GETVYRES() and GETVXRES()
    macros to take a pointer to the fbcon_display struct. This fixes the build when
    console rotation is enabled and helps the compiler again to optimize out code.
    Signed-off-by: default avatarHelge Deller <deller@gmx.de>
    Cc: stable@vger.kernel.org # v5.10+
    Signed-off-by: default avatarHelge Deller <deller@gmx.de>
    Signed-off-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
    Link: https://patchwork.freedesktop.org/patch/msgid/20220202135531.92183-4-deller@gmx.de
    a3f781a9
fbcon_cw.c 10.1 KB