Mesa (master): i965: Fix aligning to the block size in intel_miptree_copy_slice

[Neil Roberts]

Module: Mesa
Branch: master
Commit: 1a6220b416f02e56575894efbbd1717c9427c763
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=1a6220b416f02e56575894efbbd1717c9427c763

Author: Neil Roberts <neil at linux.intel.com>
Date:   Thu Jun 11 16:59:07 2015 +0100

i965: Fix aligning to the block size in intel_miptree_copy_slice

This function was trying to align the width and height to a multiple
of the block size for compressed textures. It was using align_w/h as a
shortcut to get the block size as up until Gen9 this always happens to
match. However in Gen9+ the alignment values are expressed as
multiples of the block size so in effect the alignment values are
always 4 for compressed textures as that is the minimum value we can
pick. This happened to work for most compressed formats because the
block size is also 4, but for FXT1 this was breaking because it has a
block width of 8.

This fixes some Piglit tests testing FXT1 such as

spec at 3dfx_texture_compression_fxt1@fbo-generatemipmap-formats

Reviewed-by: Nanley Chery <nanley.g.chery at intel.com>

---

 src/mesa/drivers/dri/i965/intel_mipmap_tree.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/mesa/drivers/dri/i965/intel_mipmap_tree.c b/src/mesa/drivers/dri/i965/intel_mipmap_tree.c
index 593bb9d..80c52f2 100644
--- a/src/mesa/drivers/dri/i965/intel_mipmap_tree.c
+++ b/src/mesa/drivers/dri/i965/intel_mipmap_tree.c
@@ -1211,8 +1211,10 @@ intel_miptree_copy_slice(struct brw_context *brw,
    assert(src_mt->format == dst_mt->format);
 
    if (dst_mt->compressed) {
-      height = ALIGN(height, dst_mt->align_h) / dst_mt->align_h;
-      width = ALIGN(width, dst_mt->align_w);
+      unsigned int i, j;
+      _mesa_get_format_block_size(dst_mt->format, &i, &j);
+      height = ALIGN(height, j) / j;
+      width = ALIGN(width, i);
    }
 
    /* If it's a packed depth/stencil buffer with separate stencil, the blit