Re: [PATCH v7 3/5] Documentation: Add documentation for the APM X-Gene SoC EDAC DTS binding

Loc Ho
2015-05-04T23:39:36Z

Hi,

On Mon, May 4, 2015 at 3:36 PM, Rob Herring <robherring2-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
> On Fri, May 1, 2015 at 2:59 PM, Loc Ho <lho-qTEPVZfXA3Y@public.gmane.org> wrote:
>> Hi Rob,
>>
>>>>>> I think we should first agreed on the DT binding and let's not worry
>>>>>> about APEI. Then, whether we have one file or multiple file. Again,
>>>>>> the HW consist of:
>>>>>>
>>>>>> 1. One top level interrupt and status registers
>>>
>>> For these registers, are there ECC specific functions here or just
>>> normal interrupt control/status bits (mask/unmask/status)? Assuming
>>> the later, then you should make this block an interrupt-controller.
>>> Then this is the interrupt-parent for the rest of the blocks.
>>>
>>
>> This is the only item remain before I generate an patch with just the
>> memory controller. Most of the code that I see are actually an
>> interrupt controller HW. As it is just an interrupt mask and status
>> registers, is there an example in Linux that I can model after? Also,
>> I am not quite convince as to why we can't just share the interrupt
>> and request it by each memory controller?
>
> Pretty much anything that calls irq_set_chained_handler. If you don't
> need to touch the shared registers and can set them up once at boot
> time, then you could just do shared irq handlers. But if you have to
> clear the interrupt within the PCP, you need a demuxer.
>

Thanks Rob. I look through the entire driver. Interrupts are cleared
at the source. Therefore, the next version will just register for the
shared interrupt as it is currently.

-Loc