[PATCH] drm/nouveau/fifo: map Kepler video engine contexts non-privileged

[PATCH] drm/nouveau/fifo: map Kepler video engine contexts non-privileged

[Rosen Penev]

Since the engine context rework, gk104_ectx_ctor() maps every engine
context into the channel's VMM as a privileged page.  The MSVLD,
MSPDEC and MSPPP falcons on Kepler fetch their context with
non-privileged requests, so the first method sent to any of them
faults and the channel is killed:

  fifo: fault 00 [READ] at 0000000001050000 engine 10 [MSVLD] client 0d [HUB/MSVLD] reason 05 [PRIV_VIOLATION] on channel 9
  fifo: fault 00 [READ] at 0000000001051000 engine 14 [MSPDEC] client 0b [HUB/MSPDEC] reason 05 [PRIV_VIOLATION] on channel 10
  fifo: fault 00 [READ] at 0000000001052000 engine 11 [MSPPP] client 0c [HUB/MSPPP] reason 05 [PRIV_VIOLATION] on channel 11

Before the rework, gk104_fifo_gpfifo_engine_ctor() mapped engine
contexts without the privileged bit.  Restore that for the three video
engines, and keep the privileged mapping for everything else.

Fixes: 8ab849d6dd4c ("drm/nouveau/fifo: add new engine context handling")
Signed-off-by: Rosen Penev <rosenp@gmail.com>
---
 drivers/gpu/drm/nouveau/nvkm/engine/fifo/gk104.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/fifo/gk104.c b/drivers/gpu/drm/nouveau/nvkm/engine/fifo/gk104.c
index 5655eda52a7b..912eb6c3a13d 100644
--- a/drivers/gpu/drm/nouveau/nvkm/engine/fifo/gk104.c
+++ b/drivers/gpu/drm/nouveau/nvkm/engine/fifo/gk104.c
@@ -180,6 +180,19 @@ gk104_ectx_ctor(struct nvkm_engn *engn, struct nvkm_vctx *vctx)
 	struct gf100_vmm_map_v0 args = { .priv = 1 };
 	int ret;
 
+	/* The video falcons access their context with non-privileged
+	 * requests, and fault with PRIV_VIOLATION on a privileged mapping.
+	 */
+	switch (engn->engine->subdev.type) {
+	case NVKM_ENGINE_MSVLD:
+	case NVKM_ENGINE_MSPDEC:
+	case NVKM_ENGINE_MSPPP:
+		args.priv = 0;
+		break;
+	default:
+		break;
+	}
+
 	ret = nvkm_vmm_get(vctx->vmm, 12, vctx->inst->size, &vctx->vma);
 	if (ret)
 		return ret;
-- 
2.56.0