Re: [PATCH] remoteproc: Add support for predefined notifyids

From: Arnaud POULIQUEN
Date: Wed Jan 15 2020 - 09:06:50 EST


Hi ClÃment,

On 1/15/20 11:21 AM, Clement Leger wrote:
> In order to support preallocated notify ids, if their value is
> equal to FW_RSC_NOTIFY_ID_ANY, then do no allocate a notify id
> dynamically but try to allocate the requested one. This is useful when
> using custom ids to bind them to custom vendor resources. For instance,
> it allow to assign a group of queues to a specific interrupti in order
> to dispatch notifications.
>
> Signed-off-by: Clement Leger <cleger@xxxxxxxxx>
> ---
> drivers/remoteproc/remoteproc_core.c | 27 +++++++++++++++++++--------
> include/linux/remoteproc.h | 1 +
> 2 files changed, 20 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
> index 307df98347ba..b1485fcd0f11 100644
> --- a/drivers/remoteproc/remoteproc_core.c
> +++ b/drivers/remoteproc/remoteproc_core.c
> @@ -351,14 +351,27 @@ int rproc_alloc_vring(struct rproc_vdev *rvdev, int i)
> /*
> * Assign an rproc-wide unique index for this vring
> * TODO: assign a notifyid for rvdev updates as well
> - * TODO: support predefined notifyids (via resource table)
> */
> - ret = idr_alloc(&rproc->notifyids, rvring, 0, 0, GFP_KERNEL);
> - if (ret < 0) {
> - dev_err(dev, "idr_alloc failed: %d\n", ret);
> - return ret;
> + if (rsc->vring[i].notifyid == FW_RSC_NOTIFY_ID_ANY) {
> + ret = idr_alloc(&rproc->notifyids, rvring, 0, 0, GFP_KERNEL);
> + if (ret < 0) {
> + dev_err(dev, "idr_alloc failed: %d\n", ret);
> + return ret;
> + }
> + notifyid = ret;
> +
> + /* Let the rproc know the notifyid of this vring.*/
> + rsc->vring[i].notifyid = notifyid;
> + } else {
> + /* Reserve requested notify_id */
> + notifyid = rsc->vring[i].notifyid;
> + ret = idr_alloc(&rproc->notifyids, rvring, notifyid,
> + notifyid + 1, GFP_KERNEL);
> + if (ret < 0) {
> + dev_err(dev, "idr_alloc failed: %d\n", ret);
> + return ret;
> + }
> }
> - notifyid = ret;
>
> /* Potentially bump max_notifyid */
> if (notifyid > rproc->max_notifyid)
> @@ -366,8 +379,6 @@ int rproc_alloc_vring(struct rproc_vdev *rvdev, int i)
>
> rvring->notifyid = notifyid;
>
> - /* Let the rproc know the notifyid of this vring.*/
> - rsc->vring[i].notifyid = notifyid;
> return 0;
> }
The rproc_free_vring function resets the notifyid to -1 on free.
This could generate a side effect if the resource table is not reloaded.

>
> diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h
> index 16ad66683ad0..dcae3394243e 100644
> --- a/include/linux/remoteproc.h
> +++ b/include/linux/remoteproc.h
> @@ -123,6 +123,7 @@ enum fw_resource_type {
> };
>
> #define FW_RSC_ADDR_ANY (-1)
> +#define FW_RSC_NOTIFY_ID_ANY (-1)This define can also be used in rproc_free_vring

Regards,
Arnaud
>
> /**
> * struct fw_rsc_carveout - physically contiguous memory request
>