From e9b3381715f55f4c6b0bc6bec3290fb1be338bb8 Mon Sep 17 00:00:00 2001 From: Philipp Zabel Date: Tue, 9 May 2017 18:26:57 +0200 Subject: [PATCH] etnaviv: flush color cache and depth cache together before resolves Before resolving a rendertarget or a depth/stencil resource into a texture, flush both the color cache and the depth cache together. It is unclear whether this is necessary for the following stall to work properly, or whether the depth flush just adds enough time for the color cache flush to finish before the resolver is started, but this change removes artifacts that otherwise appear if a texture is sampled directly after rendering into it. The test case is a simple QML scene graph with a QtWebEngine based WebView rendered on top of a blue background: import QtQuick 2.0 import QtQuick.Window 2.2 import QtWebView 1.1 Window { Rectangle { id: background anchors.fill: parent color: "blue" } WebView { id: webView anchors.fill: parent } Component.onCompleted: { webView.url = "" } } If the website is animated, the WebView renders the site contents into texture tiles and immediately afterwards samples from them to draw the tiles into the Qt renderbuffer. Without this patch, a small irregular triangle in the lower right of each browser tile appears solid blue, as if the texture sampler samples zeroes instead of the website contents, and the previously rendered blue Rectangle shows through. Other attempts such as adding a pipeline stall before the color flush or a TS cache flush afterwards or flushing multiple times, with stalls before and after each flush, have shown no effect. Signed-off-by: Philipp Zabel --- .../drivers/etnaviv/etnaviv_clear_blit.c | 22 +++++++++++-------- 1 file changed, 13 insertions(+), 9 deletions(-) diff --git a/src/gallium/drivers/etnaviv/etnaviv_clear_blit.c b/src/gallium/drivers/etnaviv/etnaviv_clear_blit.c index 80967be3f93..66c64445330 100644 --- a/src/gallium/drivers/etnaviv/etnaviv_clear_blit.c +++ b/src/gallium/drivers/etnaviv/etnaviv_clear_blit.c @@ -465,15 +465,19 @@ etna_try_rs_blit(struct pipe_context *pctx, ts_mem_config |= VIVS_TS_MEM_CONFIG_MSAA | msaa_format; } - uint32_t to_flush = 0; - - if (src->base.bind & PIPE_BIND_RENDER_TARGET) - to_flush |= VIVS_GL_FLUSH_CACHE_COLOR; - if (src->base.bind & PIPE_BIND_DEPTH_STENCIL) - to_flush |= VIVS_GL_FLUSH_CACHE_DEPTH; - - if (to_flush) { - etna_set_state(ctx->stream, VIVS_GL_FLUSH_CACHE, to_flush); + /* Always flush color and depth cache together before resolving. This works + * around artifacts that appear in some cases when scanning out a texture + * directly after it has been rendered to, such as rendering an animated web + * page in a QtWebEngine based WebView on GC2000. The artifacts look like + * the texture sampler samples zeroes instead of texture data in a small, + * irregular triangle in the lower right of each browser tile quad. Other + * attempts to avoid these artifacts, including a pipeline stall before the + * color flush or a TS cache flush afterwards, or flushing multiple times, + * with stalls before and after each flush, have shown no effect. */ + if (src->base.bind & PIPE_BIND_RENDER_TARGET || + src->base.bind & PIPE_BIND_DEPTH_STENCIL) { + etna_set_state(ctx->stream, VIVS_GL_FLUSH_CACHE, + VIVS_GL_FLUSH_CACHE_COLOR | VIVS_GL_FLUSH_CACHE_DEPTH); etna_stall(ctx->stream, SYNC_RECIPIENT_RA, SYNC_RECIPIENT_PE); } -- 2.30.2