Re: [PATCH 4/6] mailbox: pcc: Mark Tx as complete in PCC IRQ handler

["lihuisong (C)" <lihuisong@huawei.com>]

Hi Sudeep,

On 10/20/2025 12:08 PM, lihuisong (C) wrote:
>
> 在 2025/10/17 3:08, Sudeep Holla 写道:
>> The PCC IRQ handler clears channel-in-use and notifies clients with
>> mbox_chan_received_data(), but it does not explicitly mark the
>> transmit as complete. In IRQ completion mode this could leave Tx 
>> complete
>> waiters hanging or lead to generic timeouts in the mailbox core.
>>
>> Invoke mbox_chan_txdone() in the IRQ path once the platform has
>> acknowledged the transfer so the core can wake any waiters and update
>> state accordingly.
>>
>> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
>> ---
>>   drivers/mailbox/pcc.c | 1 +
>>   1 file changed, 1 insertion(+)
>>
>> diff --git a/drivers/mailbox/pcc.c b/drivers/mailbox/pcc.c
>> index 327e022973db..33bd2d05704b 100644
>> --- a/drivers/mailbox/pcc.c
>> +++ b/drivers/mailbox/pcc.c
>> @@ -341,6 +341,7 @@ static irqreturn_t pcc_mbox_irq(int irq, void *p)
>>        */
>>       pchan->chan_in_use = false;
>>       mbox_chan_received_data(chan, NULL);
>> +    mbox_chan_txdone(chan, 0);
> Normally, this interface is called by mbox client.
> So, IMO, this added code is not ok for mbox client.
> AFAIS, this code should be for type4, right?
> If so, the mbox client of type 4 channel has  responsibility to call 
> this interface.
I found that this patch has been merged into master.
The mbox_chan_txdone will be called twice in some mbox client drivers.
Can you take a look at my above reply? Normally, the rx_callback is used 
to wake up waiter.

/Huisong
>>         pcc_chan_acknowledge(pchan);
>>
>