• Michel Thierry's avatar
    drm/i915/gen8: Update pdp switch and point unused PDPs to scratch page · 7cb6d7ac
    Michel Thierry authored
    One important part of this patch is we now write a scratch page
    directory into any unused PDP descriptors. This matters for 2 reasons,
    first, we're not allowed to just use 0, or an invalid pointer, and second,
    we must wipe out any previous contents from the last context.
    
    The latter point only matters with full PPGTT. The former point only
    effect platforms with less than 4GB memory.
    
    v2: Updated commit message to point that we must set unused PDPs to the
    scratch page.
    
    v3: Unmap scratch_pd in gen8_ppgtt_free.
    
    v4: Initialize scratch_pd. (Mika)
    
    Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
    Signed-off-by: default avatarBen Widawsky <ben@bwidawsk.net>
    Signed-off-by: Michel Thierry <michel.thierry@intel.com> (v2+)
    Reviewed-by: default avatarMika Kuoppala <mika.kuoppala@intel.com>
    Signed-off-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
    7cb6d7ac
i915_gem_gtt.c 75.2 KB