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

Russell King - ARM Linux linux at arm.linux.org.uk
Mon May 18 03:42:24 PDT 2015

On Thu, Apr 30, 2015 at 03:19:01PM +0100, 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 at arm.com> 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.
> >
> 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.

An alternative would be to have a new function, something like
sp804_disable() which takes the virtual address of the timer.
That'd still allow the platforms to disable all timers, but
without exposing the register stuff to them.

FTTC broadband for 0.8mile line: currently at 10.5Mbps down 400kbps up
according to speedtest.net.

More information about the linux-arm-kernel mailing list