From 36e7999dc19a1a6e76258020a49f7f7836018e46 Mon Sep 17 00:00:00 2001 From: Eric Anholt Date: Mon, 3 Dec 2018 14:24:33 -0800 Subject: [PATCH] drm/v3d: Document cache flushing ABI. Right now, userspace doesn't do any L2T writes, but we should lay out our expectations for how it works. v2: Explicitly mention the VCD cache flushing requirements and that we'll flush the other caches before each of the CLs. Signed-off-by: Eric Anholt Link: https://patchwork.freedesktop.org/patch/msgid/20181203222438.25417-1-eric@anholt.net Reviewed-by: Dave Emett --- include/uapi/drm/v3d_drm.h | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/include/uapi/drm/v3d_drm.h b/include/uapi/drm/v3d_drm.h index 35c7d81..ea70669 100644 --- a/include/uapi/drm/v3d_drm.h +++ b/include/uapi/drm/v3d_drm.h @@ -52,6 +52,14 @@ extern "C" { * * This asks the kernel to have the GPU execute an optional binner * command list, and a render command list. + * + * The L1T, slice, L2C, L2T, and GCA caches will be flushed before + * each CL executes. The VCD cache should be flushed (if necessary) + * by the submitted CLs. The TLB writes are guaranteed to have been + * flushed by the time the render done IRQ happens, which is the + * trigger for out_sync. Any dirtying of cachelines by the job (only + * possible using TMU writes) must be flushed by the caller using the + * CL's cache flush commands. */ struct drm_v3d_submit_cl { /* Pointer to the binner command list. -- 2.7.4