Re: [PATCH v2] mailbox: qcom-ipcc: Log the pending interrupt during resume

[Manivannan Sadhasivam <mani@kernel.org>]

On Wed, May 11, 2022 at 12:13:24PM +0530, Sibi Sankar wrote:
> From: Prasad Sodagudi <quic_psodagud@quicinc.com>
> 
> Enable logging of the pending interrupt that triggered device wakeup. This
> logging information helps to debug IRQs that cause periodic device wakeups
> and prints the detailed information of pending IPCC interrupts instead of
> the generic "Resume caused by IRQ 17, ipcc".
> 
> Scenario: Device wakeup caused by Modem crash
> Logs:
> qcom-ipcc mailbox: virq: 182 triggered client-id: 2; signal-id: 2
> 
> From the IPCC bindings it can further understood that the client here is
> IPCC_CLIENT_MPSS and the signal was IPCC_MPROC_SIGNAL_SMP2P.
> 
> Signed-off-by: Prasad Sodagudi <quic_psodagud@quicinc.com>
> Signed-off-by: Sibi Sankar <quic_sibis@quicinc.com>
> ---
> 
> V2:
>  * Fix build error when ipcc is a module [Kernel Test Bot]
> 
>  drivers/mailbox/qcom-ipcc.c | 27 +++++++++++++++++++++++++++
>  1 file changed, 27 insertions(+)
> 
> diff --git a/drivers/mailbox/qcom-ipcc.c b/drivers/mailbox/qcom-ipcc.c
> index c5d963222014..21c071ec119c 100644
> --- a/drivers/mailbox/qcom-ipcc.c
> +++ b/drivers/mailbox/qcom-ipcc.c
> @@ -254,6 +254,28 @@ static int qcom_ipcc_setup_mbox(struct qcom_ipcc *ipcc,
>  	return devm_mbox_controller_register(dev, mbox);
>  }
>  
> +#ifdef CONFIG_PM_SLEEP

You don't need this guard anymore. Please see below.

> +static int qcom_ipcc_pm_resume(struct device *dev)
> +{
> +	struct qcom_ipcc *ipcc = dev_get_drvdata(dev);
> +	u32 hwirq;
> +	int virq;
> +
> +	hwirq = readl(ipcc->base + IPCC_REG_RECV_ID);
> +	if (hwirq == IPCC_NO_PENDING_IRQ)
> +		return 0;
> +
> +	virq = irq_find_mapping(ipcc->irq_domain, hwirq);
> +
> +	dev_info(dev, "virq: %d triggered client-id: %ld; signal-id: %ld\n", virq,
> +		 FIELD_GET(IPCC_CLIENT_ID_MASK, hwirq), FIELD_GET(IPCC_SIGNAL_ID_MASK, hwirq));
> +

Does this really need to be dev_info? This looks like a dev_dbg() material to
me.

> +	return 0;
> +}
> +#else
> +#define qcom_ipcc_pm_resume NULL
> +#endif
> +
>  static int qcom_ipcc_probe(struct platform_device *pdev)
>  {
>  	struct qcom_ipcc *ipcc;
> @@ -324,6 +346,10 @@ static const struct of_device_id qcom_ipcc_of_match[] = {
>  };
>  MODULE_DEVICE_TABLE(of, qcom_ipcc_of_match);
>  
> +static const struct dev_pm_ops qcom_ipcc_dev_pm_ops = {
> +	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(NULL, qcom_ipcc_pm_resume)
> +};
> +
>  static struct platform_driver qcom_ipcc_driver = {
>  	.probe = qcom_ipcc_probe,
>  	.remove = qcom_ipcc_remove,
> @@ -331,6 +357,7 @@ static struct platform_driver qcom_ipcc_driver = {
>  		.name = "qcom-ipcc",
>  		.of_match_table = qcom_ipcc_of_match,
>  		.suppress_bind_attrs = true,
> +		.pm = &qcom_ipcc_dev_pm_ops,

You can use the new pm_sleep_ptr() macro to avoid the PM_SLEEP guard.

		.pm = pm_sleep_ptr(&qcom_ipcc_dev_pm_ops),

Thanks,
Mani

>  	},
>  };
>  
> -- 
> 2.7.4
> 

-- 
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