Re: [PATCH v9 net-next 12/14] pds_core: add the aux client API

[Leon Romanovsky <leon@kernel.org>]

On Thu, Apr 06, 2023 at 04:41:41PM -0700, Shannon Nelson wrote:
> Add the client API operations for running adminq commands.
> The core registers the client with the FW, then the client
> has a context for requesting adminq services.  We expect
> to add additional operations for other clients, including
> requesting additional private adminqs and IRQs, but don't have
> the need yet.
> 
> Signed-off-by: Shannon Nelson <shannon.nelson@amd.com>
> ---
>  drivers/net/ethernet/amd/pds_core/auxbus.c | 135 ++++++++++++++++++++-
>  include/linux/pds/pds_auxbus.h             |  28 +++++
>  2 files changed, 160 insertions(+), 3 deletions(-)

<...>

> +static struct pds_core_ops pds_core_ops = {
> +	.adminq_cmd = pds_client_adminq_cmd,
> +};
> +

<...>

> diff --git a/include/linux/pds/pds_auxbus.h b/include/linux/pds/pds_auxbus.h
> index aa0192af4a29..f98efd578e1c 100644
> --- a/include/linux/pds/pds_auxbus.h
> +++ b/include/linux/pds/pds_auxbus.h
> @@ -10,7 +10,35 @@ struct pds_auxiliary_dev {
>  	struct auxiliary_device aux_dev;
>  	struct pci_dev *vf_pdev;
>  	struct pci_dev *pf_pdev;
> +	struct pds_core_ops *ops;

I honestly don't understand why pds_core functionality is espoused
through ops callbacks on auxdevice. IMHO, they shouldn't be callbacks
and that functionality shouldn't operate on auxdevice.

Thanks

>  	u16 client_id;
>  	void *priv;
>  };
> +
> +/*
> + *   ptrs to functions to be used by the client for core services
> + */
> +struct pds_core_ops {
> +	/* .adminq_cmd() - process an adminq request for the client
> +	 * padev:  ptr to the client device
> +	 * req:     ptr to buffer with request
> +	 * req_len: length of actual struct used for request
> +	 * resp:    ptr to buffer where answer is to be copied
> +	 * flags:   optional flags defined by enum pds_core_adminq_flags
> +	 *	    and used for more flexible adminq behvior
> +	 *
> +	 * returns 0 on success, or
> +	 *         negative for error
> +	 * Client sends pointers to request and response buffers
> +	 * Core copies request data into pds_core_client_request_cmd
> +	 * Core sets other fields as needed
> +	 * Core posts to AdminQ
> +	 * Core copies completion data into response buffer
> +	 */
> +	int (*adminq_cmd)(struct pds_auxiliary_dev *padev,
> +			  union pds_core_adminq_cmd *req,
> +			  size_t req_len,
> +			  union pds_core_adminq_comp *resp,
> +			  u64 flags);
> +};
>  #endif /* _PDSC_AUXBUS_H_ */
> -- 
> 2.17.1
>