Re: [PATCH v4 3/5] remoteproc: Add prepare/unprepare callbacks

[Paul Cercueil <paul@xxxxxxxxxxxxxxx>]

Hi Bjorn,


Le sam., déc. 21, 2019 at 12:20, Bjorn Andersson 
<bjorn.andersson@xxxxxxxxxx> a écrit :
> On Tue 10 Dec 08:40 PST 2019, Paul Cercueil wrote:
>
> >  The .prepare() callback is called before the firmware is loaded to
> >  memory. This is useful for instance in the case where some setup is
> >  required for the memory to be accessible.
>
> Would it make sense to somehow tie this prepare/unprepare to the 
> actual
> struct rproc_mem_entry that needs the resource enabled?

Do you need such granularity?

In my case, the three memories need the same clock to be enabled.

-Paul


> >  Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx>
> >  ---
> >
> >  Notes:
> >      v2-v4: No change
> >
> >   drivers/remoteproc/remoteproc_core.c | 16 +++++++++++++++-
> >   include/linux/remoteproc.h           |  4 ++++
> >   2 files changed, 19 insertions(+), 1 deletion(-)
> >
> >  diff --git a/drivers/remoteproc/remoteproc_core.c 
> > b/drivers/remoteproc/remoteproc_core.c
> >  index 0a9fc7fdd1c3..3ea5f675a148 100644
> >  --- a/drivers/remoteproc/remoteproc_core.c
> >  +++ b/drivers/remoteproc/remoteproc_core.c
> >  @@ -1299,11 +1299,19 @@ static int rproc_start(struct rproc *rproc, 
> > const struct firmware *fw)
> >   	struct device *dev = &rproc->dev;
> >   	int ret;
> >
> >  +	if (rproc->ops->prepare) {
> >  +		ret = rproc->ops->prepare(rproc);
> >  +		if (ret) {
> >  +			dev_err(dev, "Failed to prepare rproc: %d\n", ret);
> >  +			return ret;
> >  +		}
> >  +	}
> >  +
> >   	/* load the ELF segments to memory */
> >   	ret = rproc_load_segments(rproc, fw);
> >   	if (ret) {
> >   		dev_err(dev, "Failed to load program segments: %d\n", ret);
> >  -		return ret;
> >  +		goto unprepare_rproc;
> >   	}
> >
> >   	/*
> >  @@ -1354,6 +1362,9 @@ static int rproc_start(struct rproc *rproc, 
> > const struct firmware *fw)
> >   	rproc_unprepare_subdevices(rproc);
> >   reset_table_ptr:
> >   	rproc->table_ptr = rproc->cached_table;
> >  +unprepare_rproc:
> >  +	if (rproc->ops->unprepare)
> >  +		rproc->ops->unprepare(rproc);
> >
> >   	return ret;
> >   }
> >  @@ -1483,6 +1494,9 @@ static int rproc_stop(struct rproc *rproc, 
> > bool crashed)
> >
> >   	rproc->state = RPROC_OFFLINE;
> >
> >  +	if (rproc->ops->unprepare)
> >  +		rproc->ops->unprepare(rproc);
> >  +
> >   	dev_info(dev, "stopped remote processor %s\n", rproc->name);
> >
> >   	return 0;
> >  diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h
> >  index 5f201f0c86c3..a6272d1ba384 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 the device for power up (before the firmware 
> > is loaded)
> >  + * @unprepare:	unprepare the device after it is stopped
> >    * @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);
> >  +	void (*unprepare)(struct rproc *rproc);
> >   	int (*start)(struct rproc *rproc);
> >   	int (*stop)(struct rproc *rproc);
> >   	void (*kick)(struct rproc *rproc, int vqid);
> >  --
> >  2.24.0