Before this commit, if a client were to request a stencil or hiz buffer, then I830DRI2CreateBuffer() allocated and returned an X-tiled buffer by accident. (DRI2BufferStencil and DRI2BufferHiz were unintentionally caught by the default case of a switch statement.)
Now, I830DRI2CreateBuffer() correctly returns a Y-tiled buffer and handles the stencil buffer as a special case due its quirky pitch requirements. This shouldn't break older Mesa versions, because they never query (via DRI2GetBuffersWithFormat) for the drawable's DRI2BufferStencil. CC: Eric Anholt <e...@anholt.net> CC: Ian Romanick <i...@freedesktop.org> CC: Kenneth Graunke <kenn...@whitecape.org> CC: Kristian Høgsberg <k...@bitplanet.net> Signed-off-by: Chad Versace <c...@chad-versace.us> --- src/intel_dri.c | 30 ++++++++++++++++++++++++++---- 1 files changed, 26 insertions(+), 4 deletions(-) diff --git a/src/intel_dri.c b/src/intel_dri.c index 48d0f56..4bcec45 100644 --- a/src/intel_dri.c +++ b/src/intel_dri.c @@ -329,11 +329,16 @@ I830DRI2CreateBuffer(DrawablePtr drawable, unsigned int attachment, pixmap = get_front_buffer(drawable); if (pixmap == NULL) { unsigned int hint = INTEL_CREATE_PIXMAP_DRI2; + int pixmap_width = drawable->width; + int pixmap_height = drawable->height; + int pixmap_cpp = (format != 0) ? format : drawable->depth; if (intel->tiling & INTEL_TILING_3D) { switch (attachment) { case DRI2BufferDepth: case DRI2BufferDepthStencil: + case DRI2BufferStencil: + case DRI2BufferHiz: if (SUPPORTS_YTILING(intel)) { hint |= INTEL_CREATE_PIXMAP_TILING_Y; break; @@ -344,11 +349,28 @@ I830DRI2CreateBuffer(DrawablePtr drawable, unsigned int attachment, } } + /* + * The stencil buffer has quirky pitch requirements. From Vol + * 2a, 11.5.6.2.1 3DSTATE_STENCIL_BUFFER, field "Surface + * Pitch": + * The pitch must be set to 2x the value computed based on + * width, as the stencil buffer is stored with two rows + * interleaved. + * To accomplish this, we resort to the nasty hack of doubling + * the drm region's cpp and halving its height. + * + * If we neglect to double the pitch, then + * drm_intel_gem_bo_map_gtt() maps the memory incorrectly. + */ + if (attachment == DRI2BufferStencil) { + pixmap_height /= 2; + pixmap_cpp *= 2; + } + pixmap = screen->CreatePixmap(screen, - drawable->width, - drawable->height, - (format != 0) ? format : - drawable->depth, + pixmap_width, + pixmap_height, + pixmap_cpp, hint); if (pixmap == NULL || intel_get_pixmap_bo(pixmap) == NULL) { if (pixmap) -- 1.7.5.2 _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev