Re: [PATCH v4 1/5] drm/nouveau/gsp/r535: Add support for INTERNAL_GCX_ENTRY_PREREQUISITE

[David Airlie]

On Thu, Sep 17, 2026 at 8:35 AM Lyude Paul <lyude@xxxxxxxxxx> wrote:
>
> OpenRM's runtime PM handling looks a bit different then nouveau's, one part
> in particular that differs from us: OpenRM actually consults GSP to ask
> whether the GPU should be allowed to enter Gc6 and/or GcOff before runtime
> suspending the GPU. In the event the card isn't ready, runtime suspend is
> simply delayed for a few seconds before retrying.
>
> Implement the command used for querying GSP about this,
> NV2080_CTRL_CMD_INTERNAL_GCX_ENTRY_PREREQUISITE, and check to ensure that
> the GPU is ready for runtime suspend in nouveau_pmops_runtime_suspend()
> using this query. If the GPU can't be runtime suspended, update the last
> busy counter of the device and then return -EBUSY from
> nouveau_pmops_runtime_suspend() - essentially delaying the runtime suspend
> process by whatever autosuspend_delay_ms is set to.
>
> Signed-off-by: Lyude Paul <lyude@xxxxxxxxxx>
>
> ---

>  static int
>  nvkm_gsp_fini(struct nvkm_subdev *subdev, enum nvkm_suspend_state suspend)
>  {
> diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/priv.h b/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/priv.h
> index 71b7203bef507..b07797813b049 100644
> --- a/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/priv.h
> +++ b/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/priv.h
> @@ -93,6 +93,7 @@ void r535_gsp_dtor(struct nvkm_gsp *);
>  int r535_gsp_oneinit(struct nvkm_gsp *);
>  int r535_gsp_init(struct nvkm_gsp *);
>  int r535_gsp_fini(struct nvkm_gsp *, enum nvkm_suspend_state suspend);
> +int r535_gsp_gcx_ready(struct nvkm_gsp *gsp);
>
>  int nvkm_gsp_new_(const struct nvkm_gsp_fwif *, struct nvkm_device *, enum nvkm_subdev_type, int,
>                   struct nvkm_gsp **);
> diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/rm/r535/nvrm/gsp.h b/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/rm/r535/nvrm/gsp.h
> index b6683a5bf870c..fd1170037c030 100644
> --- a/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/rm/r535/nvrm/gsp.h
> +++ b/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/rm/r535/nvrm/gsp.h
> @@ -782,6 +782,13 @@ typedef struct NV2080_CTRL_INTERNAL_INTR_GET_KERNEL_TABLE_PARAMS {
>
>  #define GSP_FW_HEAP_PARAM_CLIENT_ALLOC_SIZE      ((48 << 10) * 2048)   // Support 2048 channels
>
> +#define NV2080_CTRL_CMD_INTERNAL_GCX_ENTRY_PREREQUISITE (0x2080a7d7)
> +
> +typedef struct NV2080_CTRL_INTERNAL_GCX_ENTRY_PREREQUISITE_PARAMS {
> +    NvBool bIsGC6Satisfied;
> +    NvBool bIsGCOFFSatisfied;
> +} NV2080_CTRL_INTERNAL_GCX_ENTRY_PREREQUISITE_PARAMS;
> +
>  typedef union rpc_message_rpc_union_field_v03_00

you can drop this hunk if r535 doesn't have it.

Dave.