Serieal console on Samsung S3C6410 ARM11 CPU (Was [ANNOUNCE] 3.0.6-rt17)

[jbe@pengutronix.de (Juergen Beisert)]

Hi Thomas,

Thomas Abraham wrote:
> On 8 October 2011 16:56, Juergen Beisert <jbe@pengutronix.de> wrote:
> > Thomas Gleixner wrote:
> >> I'm pleased to announce the 3.0.6-rt17 release.
> >
> > I have no idea where to search, but when I'm using the 3.0.6-rt17 on my
> > Samsung S3C6410 ARM based system, the UART (serial console) does not work
> > as expected. Typing only one char at a time is okay. Typing two chars
> > immediately makes the system using 100 % CPU load and takes about 2
> > seconds to respond. It seems the interrupt handling is broken in the UART
> > driver, but I don't know how to fix it.
> >
> > This with a simple cursor up (one char to get the last command) and a
> > small pause to the next "ENTER" char:
> >
> > root at mini6410:~ cat /proc/interrupts | grep 18:
> > ?18: ? ?5739107 ?s3c-uart ?s3c6400-uart
> >
> > Same again:
> >
> > root at mini6410:~ cat /proc/interrupts | grep 18:
> > ?18: ? ?5739113 ?s3c-uart ?s3c6400-uart
> >
> > 6 interrupts seems reasonable.
> >
> > Now with cursor up and SPACE immediately, then a pause for ENTER:
> >
> > root at mini6410:~ cat /proc/interrupts | grep 18:
> > ?18: ? ?5923815 ?s3c-uart ?s3c6400-uart
> >
> > 184702 interrupts looks strange.
>
> Just curious, do you have the following two commits?
>
> serial: samsung: Add unified interrupt handler for s3c64xx and later SoC's
> ARM: SAMSUNG: Remove uart irq handling from platform code

Are they part of the current 3.0.6 vanilla kernel? I'm only using the vanilla 
3.0.6 with rt17 on my target.

jbe

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