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

Paul Cercueil
2020-01-15T21:15:51Z

Hi Bjorn,

Le sam., déc. 21, 2019 at 12:20, Bjorn Andersson
<bjorn.andersson@linaro.org> 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@crapouillou.net>
>> ---
>>
>> 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
>>