From: Alexandre Courbot Date: Thu, 3 Mar 2016 07:38:12 +0000 (+0900) Subject: drm/nouveau/instmem/gk20a: add write barrier when releasing DMA object X-Git-Tag: v4.6-rc1~12^2~16^2~49 X-Git-Url: http://git.agner.ch/gitweb/?a=commitdiff_plain;h=e02d586da6405f8d401a90f5d19b90c3d7e2810b;p=linux.git drm/nouveau/instmem/gk20a: add write barrier when releasing DMA object When using the DMA-API for instmem, we may obtain a write-combined mapping. For such cases, add a write barrier in gk20a_instobj_release_dma() to make sure that all writes have reached memory at this time. Signed-off-by: Alexandre Courbot Signed-off-by: Ben Skeggs --- diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/instmem/gk20a.c b/drivers/gpu/drm/nouveau/nvkm/subdev/instmem/gk20a.c index 4c20fec64d96..6b8f2a19b2d9 100644 --- a/drivers/gpu/drm/nouveau/nvkm/subdev/instmem/gk20a.c +++ b/drivers/gpu/drm/nouveau/nvkm/subdev/instmem/gk20a.c @@ -228,6 +228,8 @@ gk20a_instobj_release_dma(struct nvkm_memory *memory) struct gk20a_instmem *imem = node->imem; struct nvkm_ltc *ltc = imem->base.subdev.device->ltc; + /* in case we got a write-combined mapping */ + wmb(); nvkm_ltc_invalidate(ltc); }