Re: [PATCH] clocksource: clocksource/clockevent driver for Synopsys dw_apb_timer

[Thomas Gleixner <tglx@linutronix.de>]

On Thu, 31 Mar 2011, jacob pan wrote:

> On Thu, 31 Mar 2011 17:33:12 +0200 (CEST)
> Thomas Gleixner <tglx@linutronix.de> wrote:
> 
> > On Thu, 31 Mar 2011, Jamie Iles wrote:
> > 
> > > This patch adds a driver for the Synopsys DesignWare APB timer block
> > > found in some ARM systems.  This uses the timers with an IRQ as a
> > > clockevents device and a timer without an IRQ as a clocksource
> > > device.
> > 
> > Interesting. That's probably the same thing as:
> > 
> >      arch/x86/kernel/apb_timer.c
> > 
> > So if we merge that thing, then we should make sure, that we can
> > replace the x86 one with it.
> > 
> It seems we have room to consolidate, here is my 2c:
> 1. need to support multiple timer channels
> 2. support percpu clockevent, need to deal with cpu online/offline
> 3. early boot needs. I don't know if abp timer is needed for booting on
> ARM platforms. But for Moorestown, we need timer before platform bus
> running. So I guess we cannot enumerate the timer as platform device.

That's a solvable problem. I just don't want to see two incarnations
of the same thing in the kernel. Can you folks hash that out together
what it needs to work everywhere please ?

Thanks,

	tglx