From 6950b7da7157d4d775fc09c7bc31fb0e769c4249 Mon Sep 17 00:00:00 2001 From: Keith Packard Date: Mon, 12 May 2008 13:00:55 -0700 Subject: [gem] Clarify use of explicit domain control. Remove Gen3 from I-cache usage. --- linux-core/drm-gem.txt | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) (limited to 'linux-core') diff --git a/linux-core/drm-gem.txt b/linux-core/drm-gem.txt index 8f95c206..bef437d8 100644 --- a/linux-core/drm-gem.txt +++ b/linux-core/drm-gem.txt @@ -358,6 +358,12 @@ to be generally true, this ioctl may be simplified further. necessary CPU flushing will occur and the object will be correctly synchronized with the GPU. + Note that this synchronization is not required for any accesses + going through the driver itself. The pread, pwrite and execbuffer + ioctls all perform the necessary domain management internally. + Explicit synchronization is only necessary when accessing the object + through the mmap'd address. + 7. Execution (Intel specific) Managing the command buffers is inherently chip-specific, so the core of gem @@ -475,9 +481,9 @@ to synchronize what is needed while leaving other cache contents intact. needs to be flushed to the GPU. * DRM_GEM_DOMAIN_I915_INSTRUCTION - Fragment programs on Gen3 and all of the programs on later - chips use an instruction cache to speed program execution. It must be - explicitly flushed when new programs are written to memory by the CPU. + All of the programs on Gen4 and later chips use an instruction cache to + speed program execution. It must be explicitly flushed when new programs + are written to memory by the CPU. * DRM_GEM_DOMAIN_I915_VERTEX Vertex data uses two different vertex caches, but they're -- cgit v1.2.3