Re: [PATCH v7 4/5] watchdog: qcom: add support to get the bootstatus from IMEM

[Kathiravan Thirumoorthy <kathiravan.thirumoorthy@oss.qualcomm.com>]

On 2/25/2026 6:11 PM, Konrad Dybcio wrote:
> On 2/25/26 7:43 AM, Kathiravan Thirumoorthy wrote:
>> When the system boots up after a watchdog reset, the EXPIRED_STATUS bit
>> in the WDT_STS register is cleared. To identify if the system was
>> restarted due to WDT expiry, XBL update the information in the IMEM region.
>> Update the driver to read the restart reason from IMEM and populate the
>> bootstatus accordingly.
>>
>> With the CONFIG_WATCHDOG_SYSFS enabled, user can extract the information
>> as below:
>>
>> cat /sys/devices/platform/soc@0/f410000.watchdog/watchdog/watchdog0/bootstatus
>> 32
>>
>> For backward compatibility, keep the EXPIRED_STATUS bit check. Add a new
>> function qcom_wdt_get_bootstatus() to read the restart reason from
>> IMEM.
>>
>> Signed-off-by: Kathiravan Thirumoorthy <kathiravan.thirumoorthy@oss.qualcomm.com>
>> ---
> [...]
>
>> +static int qcom_wdt_get_bootstatus(struct device *dev, struct qcom_wdt *wdt,
>> +				   u32 val)
>> +{
>> +	struct device_node *imem;
>> +	struct resource res;
>> +	void __iomem *addr;
>> +	int ret;
>> +
>> +	imem = of_parse_phandle(dev->of_node, "sram", 0);
>> +	if (!imem) {
>> +
>> +		/* Fallback to the existing check */
> Odd \n above
>
> 'existing' is imprecise, perhaps something like
>
> /* Read the EXPIRED_STATUS bit as a fallback */

Thanks, will update the comment as above in next spin.

>
> lg otherwise
>
> Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
>
> Konrad