On Fri, Apr 05, 2013 at 01:17:43PM -0700, Eric Anholt wrote:
> This still fails, since 8192*4bpp == 32768, which is too big to use the
> blitter on.
>
> v2: Be more conservative about the size of the GTT -- I'd forgotten some
> of the horror of older hardware.
Agreed on your other comments, we need to have a proper interface for
userspace to figure this out. And snoopable bos obviously need a separate
cache, otherwise we'll drown in clflush. On the patch:
Reviewed-by: Daniel Vetter <daniel.vet...@ffwll.ch>
> ---
> src/mesa/drivers/dri/intel/intel_mipmap_tree.c | 23 +++++++++++++++++++++++
> 1 file changed, 23 insertions(+)
>
> diff --git a/src/mesa/drivers/dri/intel/intel_mipmap_tree.c
> b/src/mesa/drivers/dri/intel/intel_mipmap_tree.c
> index ffdaec5..152d4631 100644
> --- a/src/mesa/drivers/dri/intel/intel_mipmap_tree.c
> +++ b/src/mesa/drivers/dri/intel/intel_mipmap_tree.c
> @@ -1703,6 +1703,25 @@ intel_miptree_map_singlesample(struct intel_context
> *intel,
> {
> struct intel_miptree_map *map;
>
> + /* Estimate the size of the mappable aperture into the GTT. There's an
> + * ioctl to get the whole GTT size, but not one to get the mappable
> subset.
> + * Generally it's 256MB, but some gen4+ (particularly things like G41)
> + * occasionally has only 128, and 830-class hardware could be either 64 or
> + * 128. Since the kernel doesn't expose information to let us actually
> + * determine the size, just be pessimistic.
> + */
> + uint32_t gtt_size = 128 * 1024 * 1024;
> + if (intel->gen == 2)
> + gtt_size = 64 * 1024 * 1024;
> +
> + /* We don't want to map two objects such that a memcpy between them would
> + * just fault one mapping in and then the other over and over forever. So
> + * we would need to divide the GTT size by 2. Additionally, some GTT is
> + * taken up by things like the framebuffer and the ringbuffer and such, so
> + * be more conservative.
> + */
> + uint32_t max_gtt_map_object_size = gtt_size / 4;
> +
> assert(mt->num_samples <= 1);
>
> map = intel_miptree_attach_map(mt, level, slice, x, y, w, h, mode);
> @@ -1749,6 +1768,10 @@ intel_miptree_map_singlesample(struct intel_context
> *intel,
> mt->region->tiling == I915_TILING_X &&
> mt->region->pitch < 32768) {
> intel_miptree_map_blit(intel, mt, map, level, slice);
> + } else if (mt->region->bo->size >= max_gtt_map_object_size) {
> + assert(mt->region->pitch < 32768 ||
> + mt->region->tiling == I915_TILING_NONE);
> + intel_miptree_map_blit(intel, mt, map, level, slice);
> } else {
> intel_miptree_map_gtt(intel, mt, map, level, slice);
> }
> --
> 1.7.10.4
>
> _______________________________________________
> mesa-dev mailing list
> mesa-dev@lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/mesa-dev
--
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch
_______________________________________________
mesa-dev mailing list
mesa-dev@lists.freedesktop.org
http://lists.freedesktop.org/mailman/listinfo/mesa-dev
