From: Marek Olšák Date: Sat, 26 Jun 2010 15:41:42 +0000 (+0200) Subject: r300g: update my notes about fastfill and zbuffer compression X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=5acdfdbf42a00352972f0f9cdd06188d0630b3dc;p=mesa.git r300g: update my notes about fastfill and zbuffer compression --- diff --git a/src/gallium/drivers/r300/r300_blit.c b/src/gallium/drivers/r300/r300_blit.c index c88f44bf2e6..97d53a14f86 100644 --- a/src/gallium/drivers/r300/r300_blit.c +++ b/src/gallium/drivers/r300/r300_blit.c @@ -86,24 +86,37 @@ static void r300_clear(struct pipe_context* pipe, double depth, unsigned stencil) { - /* XXX Implement fastfill. + /* My notes about fastfill: * - * If fastfill is enabled, a few facts should be considered: + * 1) Only the zbuffer is cleared. * - * 1) Zbuffer must be micro-tiled and whole microtiles must be - * written. + * 2) The zbuffer must be micro-tiled and whole microtiles must be + * written. If microtiling is disabled, it locks up. * - * 2) ZB_DEPTHCLEARVALUE is used to clear a zbuffer and Z Mask must be - * equal to 0. + * 3) There is Z Mask RAM which contains a compressed zbuffer and + * it interacts with fastfill. We should figure out how to use it + * to get more performance. + * This is what we know about the Z Mask: * - * 3) For 16-bit integer buffering, compression causes a hung with one or + * Each dword of the Z Mask contains compression information + * for 16 4x4 pixel blocks, that is 2 bits for each block. + * On chips with 2 Z pipes, every other dword maps to a different + * pipe. + * + * 4) ZB_DEPTHCLEARVALUE is used to clear the zbuffer and the Z Mask must + * be equal to 0. (clear the Z Mask RAM with zeros) + * + * 5) For 16-bit zbuffer, compression causes a hung with one or * two samples and should not be used. * - * 4) Fastfill must not be used if reading of compressed Z data is disabled + * 6) FORCE_COMPRESSED_STENCIL_VALUE should be enabled for stencil clears + * to avoid needless decompression. + * + * 7) Fastfill must not be used if reading of compressed Z data is disabled * and writing of compressed Z data is enabled (RD/WR_COMP_ENABLE), * i.e. it cannot be used to compress the zbuffer. - * (what the hell does that mean and how does it fit in clearing - * the buffers?) + * + * 8) ZB_CB_CLEAR does not interact with fastfill in any way. * * - Marek */ diff --git a/src/gallium/drivers/r300/r300_context.c b/src/gallium/drivers/r300/r300_context.c index 46d1ed9dbff..4e3be077d78 100644 --- a/src/gallium/drivers/r300/r300_context.c +++ b/src/gallium/drivers/r300/r300_context.c @@ -151,7 +151,7 @@ static void r300_setup_atoms(struct r300_context* r300) R300_INIT_ATOM(query_start, 4); /* Replace emission functions for r500. */ - if (r300->screen->caps.is_r500) { + if (is_r500) { r300->fs.emit = r500_emit_fs; r300->fs_rc_constant_state.emit = r500_emit_fs_rc_constant_state; r300->fs_constants.emit = r500_emit_fs_constants;