Re: [PATCH 1/2] ARM: simplify timer initialisation and remove arm_timer.h inclusion

From: Catalin Marinas
Date: Mon May 18 2015 - 06:33:19 EST


On Fri, May 15, 2015 at 07:03:34PM +0100, Sudeep Holla wrote:
> On 30/04/15 15:19, Sudeep Holla wrote:
> >On 30/04/15 15:09, Rob Herring wrote:
> >>On Thu, Apr 30, 2015 at 5:44 AM, Sudeep Holla <sudeep.holla@xxxxxxx> wrote:
> >>>The header asm/hardware/arm_timer.h is included in various machine
> >>>specific files to access TIMER_CTRL and initialise to a known state.
> >>>However that's not required as the clock{source,event} driver timer-sp
> >>>initialises all the timer being used.
> >>
> >>I believe the idea is not to initialize the timers being used, but the
> >>ones not being used and perhaps left running by the bootloader. Cases
> >>where the interrupt is shared could cause a problem.
>
> Russell, can you confirm if that's the case ?

Unless you want to test all these platforms, I would suggest we assume
this is the case. The comments even state "Initialise to a known state
(all timers off)".

> >Ah OK, makes sense. I will wait for Russell to confirm. The main idea
> >was to keep the header file having offsets local to driver/clocksource
> >and avoid sharing it in include/linux but looks like that's not possible.
>
> Since we need this driver on ARM64, we might have to end up sharing the
> header file with offsets if required for ARM platforms(though it would
> be good to avoid it if there's any better alternative solution than that)

Can you not just move the definitions to
include/clocksource/timer-sp804.h and add some SP804_ prefix to avoid
name collisions?

--
Catalin
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