Re: [PATCH v4 3/9] remoteproc: Introducing function rproc_attach()

[Bjorn Andersson <bjorn.andersson@linaro.org>]

On Mon 01 Jun 10:51 PDT 2020, Mathieu Poirier wrote:

> Introducing function rproc_attach() to enact the same actions as
> rproc_start(), but without the steps related to the handling of
> a firmware image.  That way we can properly deal with scenarios
> where the remoteproc core needs to attach with a remote processsor
> that has been booted by another entity.
> 
> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
> ---
>  drivers/remoteproc/remoteproc_core.c | 42 ++++++++++++++++++++++++++++
>  1 file changed, 42 insertions(+)
> 
> diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
> index 9f04c30c4aaf..0b323f6b554b 100644
> --- a/drivers/remoteproc/remoteproc_core.c
> +++ b/drivers/remoteproc/remoteproc_core.c
> @@ -1370,6 +1370,48 @@ static int rproc_start(struct rproc *rproc, const struct firmware *fw)
>  	return ret;
>  }
>  
> +static int __maybe_unused rproc_attach(struct rproc *rproc)
> +{
> +	struct device *dev = &rproc->dev;
> +	int ret;
> +

For the case where we're going DETACHED -> RUNNING - > OFFLINE we
need to consider the pm_runtime (and prepare/unprepare) state of the
device as well...


Apart from that I think this looks good.

Regards,
Bjorn

> +	ret = rproc_prepare_subdevices(rproc);
> +	if (ret) {
> +		dev_err(dev, "failed to prepare subdevices for %s: %d\n",
> +			rproc->name, ret);
> +		goto out;
> +	}
> +
> +	/* Attach to the remote processor */
> +	ret = rproc_attach_device(rproc);
> +	if (ret) {
> +		dev_err(dev, "can't attach to rproc %s: %d\n",
> +			rproc->name, ret);
> +		goto unprepare_subdevices;
> +	}
> +
> +	/* Start any subdevices for the remote processor */
> +	ret = rproc_start_subdevices(rproc);
> +	if (ret) {
> +		dev_err(dev, "failed to probe subdevices for %s: %d\n",
> +			rproc->name, ret);
> +		goto stop_rproc;
> +	}
> +
> +	rproc->state = RPROC_RUNNING;
> +
> +	dev_info(dev, "remote processor %s is now attached\n", rproc->name);
> +
> +	return 0;
> +
> +stop_rproc:
> +	rproc->ops->stop(rproc);
> +unprepare_subdevices:
> +	rproc_unprepare_subdevices(rproc);
> +out:
> +	return ret;
> +}
> +
>  /*
>   * take a firmware and boot a remote processor with it.
>   */
> -- 
> 2.20.1
>