drm/nv50: avoid unloading pgraph context when ctxprog is running

- We need to disable pgraph fifo access before checking the current channel,
  otherwise we could still hit a running ctxprog.
- The writes to 0x400500 are already handled by pgraph->fifo_access and are
  therefore redundant, moreover pgraph fifo access should not be reenabled
  before current context is set as invalid. So remove them altogether.

Signed-off-by: Maarten Maathuis <madman2003@gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

diff --git a/drivers/gpu/drm/nouveau/nouveau_channel.c b/drivers/gpu/drm/nouveau/nouveau_channel.c
index 343d718a9667625e4900f78f2bb757a1ebdd4fd9..2281f99da7fcef31da401ea5d31811e78e93cb93 100644 (file)
--- a/drivers/gpu/drm/nouveau/nouveau_channel.c
+++ b/drivers/gpu/drm/nouveau/nouveau_channel.c
@@ -278,12 +278,11 @@ nouveau_channel_free(struct nouveau_channel *chan)
        /* Ensure the channel is no longer active on the GPU */
        pfifo->reassign(dev, false);
 
-       if (pgraph->channel(dev) == chan) {
-               pgraph->fifo_access(dev, false);
+       pgraph->fifo_access(dev, false);
+       if (pgraph->channel(dev) == chan)
                pgraph->unload_context(dev);
-               pgraph->fifo_access(dev, true);
-       }
        pgraph->destroy_context(chan);
+       pgraph->fifo_access(dev, true);
 
        if (pfifo->channel_id(dev) == chan->id) {
                pfifo->disable(dev);

diff --git a/drivers/gpu/drm/nouveau/nv50_graph.c b/drivers/gpu/drm/nouveau/nv50_graph.c
index 20319e59d368ca1bf6b3e2368b97ccfd7e782f6b..6d504801b514823d09575b51e644395933d53122 100644 (file)
--- a/drivers/gpu/drm/nouveau/nv50_graph.c
+++ b/drivers/gpu/drm/nouveau/nv50_graph.c
@@ -165,6 +165,12 @@ nv50_graph_channel(struct drm_device *dev)
        uint32_t inst;
        int i;
 
+       /* Be sure we're not in the middle of a context switch or bad things
+        * will happen, such as unloading the wrong pgraph context.
+        */
+       if (!nv_wait(0x400300, 0x00000001, 0x00000000))
+               NV_ERROR(dev, "Ctxprog is still running\n");
+
        inst = nv_rd32(dev, NV50_PGRAPH_CTXCTL_CUR);
        if (!(inst & NV50_PGRAPH_CTXCTL_CUR_LOADED))
                return NULL;
@@ -275,7 +281,7 @@ nv50_graph_load_context(struct nouveau_channel *chan)
 int
 nv50_graph_unload_context(struct drm_device *dev)
 {
-       uint32_t inst, fifo = nv_rd32(dev, 0x400500);
+       uint32_t inst;
 
        inst  = nv_rd32(dev, NV50_PGRAPH_CTXCTL_CUR);
        if (!(inst & NV50_PGRAPH_CTXCTL_CUR_LOADED))
@@ -283,12 +289,10 @@ nv50_graph_unload_context(struct drm_device *dev)
        inst &= NV50_PGRAPH_CTXCTL_CUR_INSTANCE;
 
        nouveau_wait_for_idle(dev);
-       nv_wr32(dev, 0x400500, fifo & ~1);
        nv_wr32(dev, 0x400784, inst);
        nv_wr32(dev, 0x400824, nv_rd32(dev, 0x400824) | 0x20);
        nv_wr32(dev, 0x400304, nv_rd32(dev, 0x400304) | 0x01);
        nouveau_wait_for_idle(dev);
-       nv_wr32(dev, 0x400500, fifo);
 
        nv_wr32(dev, NV50_PGRAPH_CTXCTL_CUR, inst);
        return 0;