Re: [linux-pm] [3/6] 2.6.21-rc4: known regressions

Maxim
2007-03-28T21:27:55Z

On Wednesday 28 March 2007 22:59:26 David Brownell wrote:
> On Wednesday 28 March 2007 1:19 pm, Maxim wrote:
> > On Wednesday 28 March 2007 21:38:55 David Brownell wrote:
>
> > >
> > > Also, making HPET use the legacy mode seems like a step backwards.
>
> > It is not 'legacy' mode,
> > It is a legacy replacement mode.
>
> Typo, sorry.
>
>
> > It this mode HPET takes over IRQ0 and IRQ 8 and provides this way
> > replacement for PIT and RTC periodic function
>
> It's that RTC periodic thing that bothers me, I don't mind about
> the PIT. Remember that IRQ8 is also used for other RTC functions.
>
> Now, if there were a way to tell rtc-cmos that HPET is active,
> and arrange some kind of handshake ... that would be different.
>
> - Dave
>

Yes,
When HPET is active it eats RTC IRQ,
So the only way out is to emulate RTC using HPET,
It is done this way in old rtc driver, rtc-cmos should do the same.

Of course suspend resume is not supported at all by old rtc driver

I already wrote complete support for suspend/resume for old rtc driver (I wrote it long time ago)

Now I fixed it to support HPET , and this way I discovered that HPET doesn't have suspend resume functions

I will do last checks now and send this patch very soon

I am also planning to add support of HPET and suspend/resume for rtc-cmos, but I didn't start this yet.

Best regards,
Maxim Levitsky