Re: [PATCH 1/7] remoteproc: add prepare and unprepare ops

[Mathieu Poirier]

Good morning Suman,

I have started to work on this set - comments will come in over the next few
days...

On Tue, Mar 24, 2020 at 03:18:13PM -0500, Suman Anna wrote:
> From: Loic Pallardy <loic.pallardy@xxxxxx>
> 
> On some SoC architecture, it is needed to enable HW like
> clock, bus, regulator, memory region... before loading
> co-processor firmware.
> 
> This patch introduces prepare and unprepare ops to execute
> platform specific function before firmware loading and after
> stop execution.
> 
> Signed-off-by: Loic Pallardy <loic.pallardy@xxxxxx>
> Signed-off-by: Suman Anna <s-anna@xxxxxx>
> ---
>  drivers/remoteproc/remoteproc_core.c | 20 +++++++++++++++++++-
>  include/linux/remoteproc.h           |  4 ++++
>  2 files changed, 23 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
> index 26f6947267d2..aca6d022901a 100644
> --- a/drivers/remoteproc/remoteproc_core.c
> +++ b/drivers/remoteproc/remoteproc_core.c
> @@ -1394,12 +1394,22 @@ static int rproc_fw_boot(struct rproc *rproc, const struct firmware *fw)
>  		return ret;
>  	}
>  
> +	/* Prepare rproc for firmware loading if needed */
> +	if (rproc->ops->prepare) {
> +		ret = rproc->ops->prepare(rproc);

In my patchset on MCU synchronisation I have moved ops->{start/stop} to
remoteproc_internal.h and called them rproc_start/stop_device() (after Loic's
suggestion).  In order to be consistent and remove boiler plate code in the core
we could do the same, i.e have rproc_prepare/unprepare_device() in
remoteproc_internal.h .

With the above:
Reviewed-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>

Thanks,
Mathieu

> +		if (ret) {
> +			dev_err(dev, "can't prepare rproc %s: %d\n",
> +				rproc->name, ret);
> +			goto disable_iommu;
> +		}
> +	}
> +
>  	rproc->bootaddr = rproc_get_boot_addr(rproc, fw);
>  
>  	/* Load resource table, core dump segment list etc from the firmware */
>  	ret = rproc_parse_fw(rproc, fw);
>  	if (ret)
> -		goto disable_iommu;
> +		goto unprepare_rproc;
>  
>  	/* reset max_notifyid */
>  	rproc->max_notifyid = -1;
> @@ -1433,6 +1443,10 @@ static int rproc_fw_boot(struct rproc *rproc, const struct firmware *fw)
>  	kfree(rproc->cached_table);
>  	rproc->cached_table = NULL;
>  	rproc->table_ptr = NULL;
> +unprepare_rproc:
> +	/* release HW resources if needed */
> +	if (rproc->ops->unprepare)
> +		rproc->ops->unprepare(rproc);
>  disable_iommu:
>  	rproc_disable_iommu(rproc);
>  	return ret;
> @@ -1838,6 +1852,10 @@ void rproc_shutdown(struct rproc *rproc)
>  	/* clean up all acquired resources */
>  	rproc_resource_cleanup(rproc);
>  
> +	/* release HW resources if needed */
> +	if (rproc->ops->unprepare)
> +		rproc->ops->unprepare(rproc);
> +
>  	rproc_disable_iommu(rproc);
>  
>  	/* Free the copy of the resource table */
> diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h
> index 07bd73a6d72a..ddce7a7775d1 100644
> --- a/include/linux/remoteproc.h
> +++ b/include/linux/remoteproc.h
> @@ -355,6 +355,8 @@ enum rsc_handling_status {
>  
>  /**
>   * struct rproc_ops - platform-specific device handlers
> + * @prepare:	prepare device for code loading
> + * @unprepare:	unprepare device after stop
>   * @start:	power on the device and boot it
>   * @stop:	power off the device
>   * @kick:	kick a virtqueue (virtqueue id given as a parameter)
> @@ -371,6 +373,8 @@ enum rsc_handling_status {
>   * @get_boot_addr:	get boot address to entry point specified in firmware
>   */
>  struct rproc_ops {
> +	int (*prepare)(struct rproc *rproc);
> +	int (*unprepare)(struct rproc *rproc);
>  	int (*start)(struct rproc *rproc);
>  	int (*stop)(struct rproc *rproc);
>  	void (*kick)(struct rproc *rproc, int vqid);
> -- 
> 2.23.0
>