Re: [PATCH v22 00/11] acpi, clocksource: add GTDT driver and GTDT support in arm_arch_timer

[Mark Rutland <mark.rutland@arm.com>]

On Tue, Mar 28, 2017 at 08:34:12PM +0800, Fu Wei wrote:
> Hi Jon,
> 
> Thanks for your email
>  An hour ago, I just got some feedback from Lorenzo, will update my
> patchset ASAP according to his suggestion.
> 
> But I still need some feedback form Mark, I can see some progress here:
> https://git.kernel.org/pub/scm/linux/kernel/git/mark/linux.git/log/?h=arch-timer/gtdt
> 
> I guess I should rebase my patchset to his gtdt branch for v23.
> 
> So now, I am waiting for Mark's feedback to move on.

Sorry for the delay; I have not had the time to focus on this as I would
like to. I'm happy with patches 1-4, but from patch 5 onwards, there's
one change I'd like to see.

I'd prefer that mmio timer frame rame N was always stored at
arch_timer_mem::frame[N], rather than arch_timer_mem::frame[] being in
an arbitrary order. That will make arch_timer_mem_frame::frame_nr
redundant.

To allow arch_timer_mem::frame[] this to be sparse, I'm happy to have a
bool arch_timer_mem_frame::valid field that we set when probing each
frame. Then we don't need arch_timer_mem::num_frames.

This will make iterating over the frames far less confusing, and makes
it simple to detect when a frame number is erroneously reused.

Otherwise, I'm largely happy to pick the rest and apply any fixups
myself.

Thanks,
Mark.