Hi Mathieu,
On 3/23/21 10:19 PM, Mathieu Poirier wrote:
> Good day Arnaud,
>
> On Mon, Mar 22, 2021 at 10:26:51AM +0100, Arnaud Pouliquen wrote:
>> From: Arnaud Pouliquen <arnaud.pouliquen@xxxxxxxxxxx>
>>
>> A mechanism similar to the shutdown mailbox signal is implemented to
>> detach a remote processor.
>>
>> Upon detachment, a signal is sent to the remote firmware, allowing it
>> to perform specific actions such as stopping RPMsg communication.
>>
>> The Cortex-M hold boot is also disabled to allow the remote processor
>> to restart in case of crash.
>>
>> Notice that for this feature to be supported, the remote firmware
>> resource table must be stored at the beginning of a 1kB section
>> (default size provided to the remoteproc core).
>>
>> This restriction should be lifted in the future by using a backup
>> register to store the actual size of the resource table.
>
> I'm not sure the above two paragraphs add anything valuable to the changelog.
> At this time the size of 1kB is fixed and future enhancement are, well, in the
> future. So for now this patch is working with the rest of the current
> environment and that is the important part.
>
>>
>> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@xxxxxxxxxxx>
>> ---
>> drivers/remoteproc/stm32_rproc.c | 38 ++++++++++++++++++++++++++++++--
>> 1 file changed, 36 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/remoteproc/stm32_rproc.c b/drivers/remoteproc/stm32_rproc.c
>> index 3d45f51de4d0..298ef5b19e27 100644
>> --- a/drivers/remoteproc/stm32_rproc.c
>> +++ b/drivers/remoteproc/stm32_rproc.c
>> @@ -28,7 +28,7 @@
>> #define RELEASE_BOOT 1
>>
>> #define MBOX_NB_VQ 2
>> -#define MBOX_NB_MBX 3
>> +#define MBOX_NB_MBX 4
>>
>> #define STM32_SMC_RCC 0x82001000
>> #define STM32_SMC_REG_WRITE 0x1
>> @@ -38,6 +38,7 @@
>> #define STM32_MBX_VQ1 "vq1"
>> #define STM32_MBX_VQ1_ID 1
>> #define STM32_MBX_SHUTDOWN "shutdown"
>> +#define STM32_MBX_DETACH "detach"
>>
>> #define RSC_TBL_SIZE 1024
>>
>> @@ -336,6 +337,15 @@ static const struct stm32_mbox stm32_rproc_mbox[MBOX_NB_MBX] = {
>> .tx_done = NULL,
>> .tx_tout = 500, /* 500 ms time out */
>> },
>> + },
>> + {
>> + .name = STM32_MBX_DETACH,
>> + .vq_id = -1,
>> + .client = {
>> + .tx_block = true,
>> + .tx_done = NULL,
>> + .tx_tout = 200, /* 200 ms time out to detach should be fair enough */
>> + },
>> }
>> };
>>
>> @@ -461,6 +471,25 @@ static int stm32_rproc_attach(struct rproc *rproc)
>> return stm32_rproc_set_hold_boot(rproc, true);
>> }
>>
>> +static int stm32_rproc_detach(struct rproc *rproc)
>> +{
>> + struct stm32_rproc *ddata = rproc->priv;
>> + int err, dummy_data, idx;
>> +
>> + /* Inform the remote processor of the detach */
>> + idx = stm32_rproc_mbox_idx(rproc, STM32_MBX_DETACH);
>> + if (idx >= 0 && ddata->mb[idx].chan) {
>> + /* A dummy data is sent to allow to block on transmit */
>> + err = mbox_send_message(ddata->mb[idx].chan,
>> + &dummy_data);
>> + if (err < 0)
>> + dev_warn(&rproc->dev, "warning: remote FW detach without ack\n");
>> + }
>> +
>> + /* Allow remote processor to auto-reboot */
>> + return stm32_rproc_set_hold_boot(rproc, false);
>> +}
>> +
>> static int stm32_rproc_stop(struct rproc *rproc)
>> {
>> struct stm32_rproc *ddata = rproc->priv;
>> @@ -597,7 +626,11 @@ stm32_rproc_get_loaded_rsc_table(struct rproc *rproc, size_t *table_sz)
>> }
>>
>> done:
>> - /* Assuming the resource table fits in 1kB is fair */
>> + /*
>> + * Assuming the resource table fits in 1kB is fair.
>> + * Notice for the detach, that this 1 kB memory area has to be reserved in the coprocessor
>> + * firmware for the resource table. A clean of this whole area is done on detach.
>> + */
>
> Can you rework the last sentence? I'm not sure if it means the M4 will clean
> the resource table or if that should be the application processor... I'm also
> not clear on what you mean by "clean". Usually it means zero'ing out but in
> this case it means a re-initialisation of the original values.
This is done by the remoteproc core itself by overwriting the resource table
area with the rproc->clean_table backup.
i will rework the comment in this way.
Thanks,
Arnaud
>
>
>> *table_sz = RSC_TBL_SIZE;
>> return (struct resource_table *)ddata->rsc_va;
>> }
>> @@ -607,6 +640,7 @@ static const struct rproc_ops st_rproc_ops = {
>> .start = stm32_rproc_start,
>> .stop = stm32_rproc_stop,
>> .attach = stm32_rproc_attach,
>> + .detach = stm32_rproc_detach,
>
> With the above:
>
> Reviewed-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
>
>> .kick = stm32_rproc_kick,
>> .load = rproc_elf_load_segments,
>> .parse_fw = stm32_rproc_parse_fw,
>> --
>> 2.17.1
>>
