• Chris Wilson's avatar
    drm/i915: Declare the swizzling unknown for L-shaped configurations · 19ee835c
    Chris Wilson authored
    The old style of memory interleaving swizzled upto the end of the
    first even bank of memory, and then used the remainder as unswizzled on
    the unpaired bank - i.e. swizzling is not constant for all memory. This
    causes problems when we try to migrate memory and so the kernel prevents
    migration at all when we detect L-shaped inconsistent swizzling.
    However, this issue also extends to userspace who try to manually detile
    into memory as the swizzling for an individual page is unknown (it
    depends on its physical address only known to the kernel), userspace
    cannot correctly swizzle objects.
    
    v2: Mark the global swizzling as unknown rather than adjust the value
    reported to userspace.
    
    Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=91105Signed-off-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
    Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
    Cc: stable@vger.kernel.org
    Signed-off-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
    19ee835c
i915_gem_tiling.c 17.3 KB