On Tue, Aug 19, 2025 at 10:24:36PM +0530, Mukesh Ojha wrote:
> Currently, remoteproc and non-remoteproc subsystems use different
> variants of the MDT loader helper API, primarily due to the handling of
> the metadata context. Remoteproc subsystems retain this context until
> authentication and reset, while non-remoteproc subsystems (e.g., video,
> graphics) do not require it.
>
> Unify the metadata loading process for both remoteproc and
> non-remoteproc subsystems by introducing a dedicated PAS context
> initialization function.
>
> By introducing qcom_scm_pas_ctx_init(), we can standardize the API usage
> across subsystems and reduce the number of parameters passed to MDT
> loader functions, improving code clarity and maintainability.
>
> Signed-off-by: Mukesh Ojha <mukesh.ojha@xxxxxxxxxxxxxxxx>
> ---
> drivers/firmware/qcom/qcom_scm.c | 26 ++++++++++++++++++++++++++
> include/linux/firmware/qcom/qcom_scm.h | 11 +++++++++++
> 2 files changed, 37 insertions(+)
>
> diff --git a/drivers/firmware/qcom/qcom_scm.c b/drivers/firmware/qcom/qcom_scm.c
> index 96d5cf40a74c..33187d4f4aef 100644
> --- a/drivers/firmware/qcom/qcom_scm.c
> +++ b/drivers/firmware/qcom/qcom_scm.c
> @@ -558,6 +558,32 @@ static void qcom_scm_set_download_mode(u32 dload_mode)
> dev_err(__scm->dev, "failed to set download mode: %d\n", ret);
> }
>
> +void *qcom_scm_pas_ctx_init(struct device *dev, u32 peripheral, phys_addr_t mem_phys,
> + size_t mem_size, bool save_mdt_ctx)
Since we export this for other drivers/module, consider adding kerneldoc
comments.
> +{
> + struct qcom_scm_pas_ctx *ctx;
> +
> + ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
> + if (!ctx)
> + return NULL;
> +
> + ctx->dev = dev;
> + ctx->peripheral = peripheral;
> + ctx->mem_phys = mem_phys;
> + ctx->mem_size = mem_size;
> + ctx->save_mdt_ctx = save_mdt_ctx;
> + ctx->metadata = NULL;
This seems unnecessary.
> +
> + if (save_mdt_ctx) {
> + ctx->metadata = devm_kzalloc(dev, sizeof(*ctx->metadata), GFP_KERNEL);
> + if (!ctx->metadata)
> + return NULL;
Do we really need to pass this burden to the caller to pass save_mdt_ctx
as true/false? What happens if we always keep metadata in qcom_scm_pas_ctx struct
and let clients use it if needed.
> + }
> +
> + return ctx;
> +}
> +EXPORT_SYMBOL_GPL(qcom_scm_pas_ctx_init);
Is there an equivalant ctx_destroy() function? It would be confusing for
drivers to call this in their probe and not doing anything upon error or
in their bus::remove callbacks. I don't know if we really want to
convert the whole function under devres or just provide a destroy
callback.
> +
> /**
> * qcom_scm_pas_init_image() - Initialize peripheral authentication service
> * state machine for a given peripheral, using the
> diff --git a/include/linux/firmware/qcom/qcom_scm.h b/include/linux/firmware/qcom/qcom_scm.h
> index a55ca771286b..b7eb206561a9 100644
> --- a/include/linux/firmware/qcom/qcom_scm.h
> +++ b/include/linux/firmware/qcom/qcom_scm.h
> @@ -72,6 +72,17 @@ struct qcom_scm_pas_metadata {
> ssize_t size;
> };
>
> +struct qcom_scm_pas_ctx {
> + struct device *dev;
> + u32 peripheral;
> + phys_addr_t mem_phys;
> + size_t mem_size;
> + struct qcom_scm_pas_metadata *metadata;
> + bool save_mdt_ctx;
As mentioned above, can we just include qcom_scm_pas_metadata struct all
the time?
Thanks,
Pavan
