Re: [PATCH 0/2] Alchemy: fix interrupt routing

[Sergei Shtylyov <sshtylyov@ru.mvista.com>]

Ralf Baechle wrote:

>>   It works:

>>41 total events, 5.109 events/sec

> That's the expected behaviour, good.

> One of the remaining problems on some platforms with tickless kernels is
> that not all clocksource / clockevent driver combinations are playing
> nicely with each other.  You can switch the clocksource driver manually
> at runtime.  First let's see what clocksource we have:
> 
>   # cd /sys/devices/system/clocksource/clocksource0/
>   # cat available_clocksource 
>   MIPS pit jiffies 

    I only have MIPS and jiffies of course. :-)

>   # cat current_clocksource 
>   MIPS 

> MIPS is the CP0 count register.  pit is the i8259 and jiffies simply counts
> interrupts like in the old days so has problems with lost timer interrupts
> and generally not such a great idea for tickless.  You should be able to
> switch between all these drivers by something like:

>   # echo jiffies > current_clocksource
>   Time: jiffies clocksource has been installed.
>   #

> Try switching between all the available clocksources a few times to see if
> that's working right also.

    It died after I selected jiffies.

>    Ralf

WBR, Sergei