Re: [PATCH 3/4] ASoC: SOF: amd: Handle IPC replies before FW_BOOT_COMPLETE

[Cristian Ciocaltea <cristian.ciocaltea@collabora.com>]

On 2/7/25 1:55 PM, Mukunda,Vijendar wrote:
> On 07/02/25 17:16, Cristian Ciocaltea wrote:
>> In some cases, e.g. during resuming from suspend, there is a possibility
>> that some IPC reply messages get received by the host while the DSP
>> firmware has not yet reached the complete boot state.
>>
>> Detect when this happens and do not attempt to process the unexpected
>> replies from DSP.  Instead, provide proper debugging support.
> As per our understanding, before FW boot completion there won't
> be any IPC responses sent from Firmware.
> In this case, do we really need such a condition check?

During the suspend/resume stress testing I was able to get this kind of
messages, and that's the actual reason for introducing the verification.

Also it doesn't seem to be uncommon, e.g. Intel HDA IPC also provides
similar checks.

>>
>> Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com>
>> ---
>>  sound/soc/sof/amd/acp-ipc.c | 23 ++++++++++++++++-------
>>  1 file changed, 16 insertions(+), 7 deletions(-)
>>
>> diff --git a/sound/soc/sof/amd/acp-ipc.c b/sound/soc/sof/amd/acp-ipc.c
>> index 5f371d9263f3bad507236ace95b7ef323c369187..12caefd08788595be8de03a863b88b5bbc15847d 100644
>> --- a/sound/soc/sof/amd/acp-ipc.c
>> +++ b/sound/soc/sof/amd/acp-ipc.c
>> @@ -167,6 +167,7 @@ irqreturn_t acp_sof_ipc_irq_thread(int irq, void *context)
>>  
>>  	if (sdev->first_boot && sdev->fw_state != SOF_FW_BOOT_COMPLETE) {
>>  		acp_mailbox_read(sdev, sdev->dsp_box.offset, &status, sizeof(status));
>> +
>>  		if ((status & SOF_IPC_PANIC_MAGIC_MASK) == SOF_IPC_PANIC_MAGIC) {
>>  			snd_sof_dsp_panic(sdev, sdev->dsp_box.offset + sizeof(status),
>>  					  true);
>> @@ -188,13 +189,21 @@ irqreturn_t acp_sof_ipc_irq_thread(int irq, void *context)
>>  
>>  	dsp_ack = snd_sof_dsp_read(sdev, ACP_DSP_BAR, ACP_SCRATCH_REG_0 + dsp_ack_write);
>>  	if (dsp_ack) {
>> -		spin_lock_irq(&sdev->ipc_lock);
>> -		/* handle immediate reply from DSP core */
>> -		acp_dsp_ipc_get_reply(sdev);
>> -		snd_sof_ipc_reply(sdev, 0);
>> -		/* set the done bit */
>> -		acp_dsp_ipc_dsp_done(sdev);
>> -		spin_unlock_irq(&sdev->ipc_lock);
>> +		if (likely(sdev->fw_state == SOF_FW_BOOT_COMPLETE)) {
>> +			spin_lock_irq(&sdev->ipc_lock);
>> +
>> +			/* handle immediate reply from DSP core */
>> +			acp_dsp_ipc_get_reply(sdev);
>> +			snd_sof_ipc_reply(sdev, 0);
>> +			/* set the done bit */
>> +			acp_dsp_ipc_dsp_done(sdev);
>> +
>> +			spin_unlock_irq(&sdev->ipc_lock);
>> +		} else {
>> +			dev_dbg_ratelimited(sdev->dev, "IPC reply before FW_BOOT_COMPLETE: %#x\n",
>> +					    dsp_ack);
>> +		}
>> +
>>  		ipc_irq = true;
>>  	}
>>  
>>
>