Hello Bjorn
On 4/13/21 11:34 PM, Bjorn Andersson wrote:
> On Wed 31 Mar 02:33 CDT 2021, Arnaud Pouliquen wrote:
>
>> 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.
>>
>> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@xxxxxxxxxxx>
>> Reviewed-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
>> Tested-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
>> ---
>> drivers/remoteproc/stm32_rproc.c | 39 ++++++++++++++++++++++++++++++--
>> 1 file changed, 37 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/remoteproc/stm32_rproc.c b/drivers/remoteproc/stm32_rproc.c
>> index 3d45f51de4d0..7353f9e7e7af 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);
>
> Seems I posted my comment on v1, rather than this latest version. Please
> let me know if we should do anything about this dummy_data.
Thanks for pointing this out, you are right, the mailbox driver is stm32_ipcc
and it only sends a signal to the remote processor.
As message can be queued by the mailbox framework using a local variable seems
not a good option. As this code is a copy/past of the kick and stop?
I propose to get this one and I will send a new patch to fix the usage in the
whole driver.
Thanks,
Arnaud
>
> Regards,
> Bjorn
>
>> + 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 +626,12 @@ 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. On detach, the remoteproc core re-initializes this
>> + * entire area by overwriting it with the initial values stored in rproc->clean_table.
>> + */
>> *table_sz = RSC_TBL_SIZE;
>> return (struct resource_table *)ddata->rsc_va;
>> }
>> @@ -607,6 +641,7 @@ static const struct rproc_ops st_rproc_ops = {
>> .start = stm32_rproc_start,
>> .stop = stm32_rproc_stop,
>> .attach = stm32_rproc_attach,
>> + .detach = stm32_rproc_detach,
>> .kick = stm32_rproc_kick,
>> .load = rproc_elf_load_segments,
>> .parse_fw = stm32_rproc_parse_fw,
>> --
>> 2.17.1
>>
