Re: [PATCH v2 5/8] irqchip/qcom-pdc: Configure PDC to pass through mode

[Maulik Shah (mkshah)]

On 6/11/2026 4:35 PM, Konrad Dybcio wrote:
> On 5/26/26 12:54 PM, Maulik Shah wrote:
>> All PDC irqchip supports pass through mode in which both Direct SPIs and
>> GPIO IRQs (as SPIs) are sent to GIC without latching at PDC.
>>
>> Newer PDCs (v3.0 onwards) also support additional secondary controller mode
>> where PDC latches GPIO IRQs and sends to GIC as level type IRQ. Direct SPIs
>> still works same as pass through mode without latching at PDC even in
>> secondary controller mode.
>>
>> All the SoCs so far default uses pass through mode with the exception of
>> x1e. x1e PDC may be set to secondary controller mode for builds on CRD
>> boards whereas it may be set to pass through mode for IoT-EVK boards.
>> The mode configuration is done in firmware and initially shipped windows
>> firmware did not have SCM interface to read or modify the PDC mode.
>> Later only write access is opened up for non secure world.
>>
>> Using the write access available add changes to modify the PDC mode to
>> pass through mode via SCM write. When the write fails (on older firmware)
>> assume to work in secondary mode.
>>
>> Co-developed-by: Sneh Mankad <sneh.mankad@xxxxxxxxxxxxxxxx>
>> Signed-off-by: Sneh Mankad <sneh.mankad@xxxxxxxxxxxxxxxx>
>> Signed-off-by: Maulik Shah <maulik.shah@xxxxxxxxxxxxxxxx>
>> ---
> 
> [...]
> 
>> +static inline bool pdc_pin_uses_seconary_mode(int pin_out)
> 
> Please add a comment somewhere near here, repeating what you said in
> the previous commit message (about the SPIs being mapped first, followed
> by GPIO-as-SPIs)

Sure. Will add comment in v3.

Thanks,
Maulik