[PATCH] Revert "drm/nouveau/fifo/gk104: kick channels when deactivating them"

[Alexandre Courbot]

This reverts commit 1addc1264852

This commit seems to cause crashes in gk104_fifo_intr_runlist() by
returning 0xbad0da00 when register 0x2a00 is read. Since this commit was
intended for GM20B which is not completely supported yet, let's revert
it for the time being.

Reported-by: Eric Biggers <ebiggers3 at gmail.com>
Signed-off-by: Alexandre Courbot <acourbot at nvidia.com>
---
David, it would be great if this could be merged for 4.2 since lots of
users could potentially experience this issue. Thanks!

 drivers/gpu/drm/nouveau/nvkm/engine/fifo/gk104.c | 29 +++++++-----------------
 1 file changed, 8 insertions(+), 21 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/fifo/gk104.c 
b/drivers/gpu/drm/nouveau/nvkm/engine/fifo/gk104.c
index 52c22b026005..e10f9644140f 100644
--- a/drivers/gpu/drm/nouveau/nvkm/engine/fifo/gk104.c
+++ b/drivers/gpu/drm/nouveau/nvkm/engine/fifo/gk104.c
@@ -166,30 +166,14 @@ gk104_fifo_context_attach(struct nvkm_object *parent,
 }

 static int
-gk104_fifo_chan_kick(struct gk104_fifo_chan *chan)
-{
-       struct nvkm_object *obj = (void *)chan;
-       struct gk104_fifo_priv *priv = (void *)obj->engine;
-
-       nv_wr32(priv, 0x002634, chan->base.chid);
-       if (!nv_wait(priv, 0x002634, 0x100000, 0x000000)) {
-               nv_error(priv, "channel %d [%s] kick timeout\n",
-                        chan->base.chid, nvkm_client_name(chan));
-               return -EBUSY;
-       }
-
-       return 0;
-}
-
-static int
 gk104_fifo_context_detach(struct nvkm_object *parent, bool suspend,
                          struct nvkm_object *object)
 {
        struct nvkm_bar *bar = nvkm_bar(parent);
+       struct gk104_fifo_priv *priv = (void *)parent->engine;
        struct gk104_fifo_base *base = (void *)parent->parent;
        struct gk104_fifo_chan *chan = (void *)parent;
        u32 addr;
-       int ret;

        switch (nv_engidx(object->engine)) {
        case NVDEV_ENGINE_SW    : return 0;
@@ -204,9 +188,13 @@ gk104_fifo_context_detach(struct nvkm_object *parent, bool 
suspend,
                return -EINVAL;
        }

-       ret = gk104_fifo_chan_kick(chan);
-       if (ret && suspend)
-               return ret;
+       nv_wr32(priv, 0x002634, chan->base.chid);
+       if (!nv_wait(priv, 0x002634, 0xffffffff, chan->base.chid)) {
+               nv_error(priv, "channel %d [%s] kick timeout\n",
+                        chan->base.chid, nvkm_client_name(chan));
+               if (suspend)
+                       return -EBUSY;
+       }

        if (addr) {
                nv_wo32(base, addr + 0x00, 0x00000000);
@@ -331,7 +319,6 @@ gk104_fifo_chan_fini(struct nvkm_object *object, bool 
suspend)
                gk104_fifo_runlist_update(priv, chan->engine);
        }

-       gk104_fifo_chan_kick(chan);
        nv_wr32(priv, 0x800000 + (chid * 8), 0x00000000);
        return nvkm_fifo_channel_fini(&chan->base, suspend);
 }
-- 
2.5.0