[PATCH 1/2] nouveau: handle EBUSY and EAGAIN for GSP aux errors.

[Ben Skeggs]

On 11/11/24 13:41, Dave Airlie wrote:

> From: Dave Airlie <airlied at redhat.com>
>
> The upper layer transfer functions expect EBUSY as a return
> for when retries should be done.
>
> Fix the AUX error translation, but also check for both errors
> in a few places.
>
> Fixes: eb284f4b3781 ("drm/nouveau/dp: Honor GSP link training retry timeouts")
> Signed-off-by: Dave Airlie <airlied at redhat.com>
> ---
>   drivers/gpu/drm/nouveau/nvkm/engine/disp/r535.c | 2 +-
>   drivers/gpu/drm/nouveau/nvkm/subdev/gsp/r535.c  | 6 +++---
>   2 files changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/nouveau/nvkm/engine/disp/r535.c b/drivers/gpu/drm/nouveau/nvkm/engine/disp/r535.c
> index 027867c2a8c5..8f9aa3463c3c 100644
> --- a/drivers/gpu/drm/nouveau/nvkm/engine/disp/r535.c
> +++ b/drivers/gpu/drm/nouveau/nvkm/engine/disp/r535.c
> @@ -992,7 +992,7 @@ r535_dp_train_target(struct nvkm_outp *outp, u8 target, bool mst, u8 link_nr, u8
>   		ctrl->data = data;
>   
>   		ret = nvkm_gsp_rm_ctrl_push(&disp->rm.objcom, &ctrl, sizeof(*ctrl));
> -		if (ret == -EAGAIN && ctrl->retryTimeMs) {
> +		if ((ret == -EAGAIN || ret == -EBUSY) && ctrl->retryTimeMs) {

You can remove handling of -EAGAIN here (and the cases below), as 
nothing can return it after the change to r535_rpc_status_to_errno() in 
this commit.

>   			/*
>   			 * Device (likely an eDP panel) isn't ready yet, wait for the time specified
>   			 * by GSP before retrying again
> diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/r535.c b/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/r535.c
> index cf58f9da9139..d586aea30898 100644
> --- a/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/r535.c
> +++ b/drivers/gpu/drm/nouveau/nvkm/subdev/gsp/r535.c
> @@ -78,7 +78,7 @@ r535_rpc_status_to_errno(uint32_t rpc_status)
>   	switch (rpc_status) {
>   	case 0x55: /* NV_ERR_NOT_READY */
>   	case 0x66: /* NV_ERR_TIMEOUT_RETRY */
> -		return -EAGAIN;
> +		return -EBUSY;
>   	case 0x51: /* NV_ERR_NO_MEMORY */
>   		return -ENOMEM;
>   	default:
> @@ -601,7 +601,7 @@ r535_gsp_rpc_rm_alloc_push(struct nvkm_gsp_object *object, void *argv, u32 repc)
>   
>   	if (rpc->status) {
>   		ret = ERR_PTR(r535_rpc_status_to_errno(rpc->status));
> -		if (PTR_ERR(ret) != -EAGAIN)
> +		if (PTR_ERR(ret) != -EAGAIN && PTR_ERR(ret) != -EBUSY)
>   			nvkm_error(&gsp->subdev, "RM_ALLOC: 0x%x\n", rpc->status);
>   	} else {
>   		ret = repc ? rpc->params : NULL;
> @@ -660,7 +660,7 @@ r535_gsp_rpc_rm_ctrl_push(struct nvkm_gsp_object *object, void **argv, u32 repc)
>   
>   	if (rpc->status) {
>   		ret = r535_rpc_status_to_errno(rpc->status);
> -		if (ret != -EAGAIN)
> +		if (ret != -EAGAIN && ret != -EBUSY)
>   			nvkm_error(&gsp->subdev, "cli:0x%08x obj:0x%08x ctrl cmd:0x%08x failed: 0x%08x\n",
>   				   object->client->object.handle, object->handle, rpc->cmd, rpc->status);
>   	}