Re: [PATCH v4 7/7] irqchip: qcom-pdc: Reset all pdc interrupts during init

From: Stephen Boyd
Date: Fri Aug 14 2020 - 16:24:46 EST


Quoting Maulik Shah (2020-08-13 00:30:44)
> Hi,
>
> On 8/12/2020 3:01 AM, Stephen Boyd wrote:
> > Quoting Maulik Shah (2020-08-10 04:21:00)
> >> Clear previous kernel's configuration during init by resetting
> >> interrupts in enable bank to zero.
> > Can you please add some more information here about why we're not
> > clearing all the pdc irqs and only the ones that are listed in DT?
> sure.
> > Is
> > that because the pdc is shared between exception levels of the CPU and
> > so some irqs shouldn't be used? Does the DT binding need to change to
> > only list the hwirqs that are usable by the OS instead of the ones that
> > are usable for the entire system? The binding doesn't mention this at
> > all so I am just guessing here.
>
> The IRQs specified in qcom,pdc-ranges property in DT are the only ones
> that can be used in the current OS for the PDC.
>
> So instead of setting entire register to zero (each reg supports 32
> interrupts enable bit) only clearing the ones that can be used.
>

Ok. Is something wrong with setting all the register bits to 0? Is there
something else in those registers that shouldn't be touched? Please add
these details to the commit message.