drm/nouveau/fifo: allow direct access to channel control registers where possible

The indirect method has been left in-place here as a fallback path, as
it may not be possible to map the non-PAGE_SIZE aligned control areas
across some chipset+interface combinations.

This isn't a problem for the primary use-case where the core and drm
are linked together in kernel-land, but across a VM or (in the case
where it applies now) between the core in the kernel and a userspace
test tool.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/gpu/drm/nouveau/core/include/engine/fifo.h b/drivers/gpu/drm/nouveau/core/include/engine/fifo.h
index 83567124d3b5..b53f9d8022fe 100644
--- a/drivers/gpu/drm/nouveau/core/include/engine/fifo.h
+++ b/drivers/gpu/drm/nouveau/core/include/engine/fifo.h
@@ -10,6 +10,7 @@ struct nouveau_fifo_chan {
 	struct nouveau_dmaobj *pushdma;
 	struct nouveau_gpuobj *pushgpu;
 	void __iomem *user;
+	u64 addr;
 	u32 size;
 	u16 chid;
 	atomic_t refcnt; /* NV04_NVSW_SET_REF */
@@ -40,6 +41,7 @@ void nouveau_fifo_channel_destroy(struct nouveau_fifo_chan *);
 #define _nouveau_fifo_channel_fini _nouveau_namedb_fini
 
 void _nouveau_fifo_channel_dtor(struct nouveau_object *);
+int  _nouveau_fifo_channel_map(struct nouveau_object *, u64 *, u32 *);
 u32  _nouveau_fifo_channel_rd32(struct nouveau_object *, u64);
 void _nouveau_fifo_channel_wr32(struct nouveau_object *, u64, u32);