drm/nouveau/mc: add nvkm_mc_enabled() function

Add a function that allows us to query whether a given subdev is
currently enabled or not.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

diff --git a/drivers/gpu/drm/nouveau/include/nvkm/subdev/mc.h b/drivers/gpu/drm/nouveau/include/nvkm/subdev/mc.h
index 27d25b1..e68ba63 100644 (file)
--- a/drivers/gpu/drm/nouveau/include/nvkm/subdev/mc.h
+++ b/drivers/gpu/drm/nouveau/include/nvkm/subdev/mc.h
@@ -9,6 +9,7 @@ struct nvkm_mc {
 
 void nvkm_mc_enable(struct nvkm_device *, enum nvkm_devidx);
 void nvkm_mc_disable(struct nvkm_device *, enum nvkm_devidx);
+bool nvkm_mc_enabled(struct nvkm_device *, enum nvkm_devidx);
 void nvkm_mc_reset(struct nvkm_device *, enum nvkm_devidx);
 void nvkm_mc_intr(struct nvkm_device *, bool *handled);
 void nvkm_mc_intr_unarm(struct nvkm_device *);

diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/mc/base.c b/drivers/gpu/drm/nouveau/nvkm/subdev/mc/base.c
index 6b25e25..09f669a 100644 (file)
--- a/drivers/gpu/drm/nouveau/nvkm/subdev/mc/base.c
+++ b/drivers/gpu/drm/nouveau/nvkm/subdev/mc/base.c
@@ -161,6 +161,16 @@ nvkm_mc_enable(struct nvkm_device *device, enum nvkm_devidx devidx)
        }
 }
 
+bool
+nvkm_mc_enabled(struct nvkm_device *device, enum nvkm_devidx devidx)
+{
+       u64 pmc_enable = nvkm_mc_reset_mask(device, false, devidx);
+
+       return (pmc_enable != 0) &&
+              ((nvkm_rd32(device, 0x000200) & pmc_enable) == pmc_enable);
+}
+
+
 static int
 nvkm_mc_fini(struct nvkm_subdev *subdev, bool suspend)
 {