[okl4-developer] does linux(Wombat) re-configure UART when booting?

[kashin Lin]

Hi Jorge,

1. does the "printf" function's implementation ( in libs\c ) use  iguana
serial driver too?

2. if the situation i got isn't due to
printk's implementation, how can i debug for this case?
    ( it just stopped after "Backed PXA serial", no more messages... )

thanks for your answering


2007/9/13, Jorge Torres <jorge.torres.maldonado at gmail.com>:
>
> Hi Kashin,
>
> I believe that wombat uses the iguana serial driver,
>
> Cheers,
>
> Jorge
>
> On 9/12/07, kashin Lin < kashin08 at gmail.com> wrote:
> >
> > Hi,
> >
> > so do you think what may cause this situation happened?
> > ( the output just stopped after "*Backed PXA serial*" as i mentioned in
> > last letter )
> >
> > the system crash ? or the linux kernel just output messages by different
> > way (ex: not through RS232 or it use different UART setting) ?
> >
> > thanks for your suggestions.
> >
> >
> > 2007/9/12, Jorge Torres <jorge.torres.maldonado at gmail.com>:
> > >
> > > Hi Kashin,
> > >
> > > Printk is used for outputs inside the Linux kernel in an interrupt
> > > context and process context, meaning that it will allways happen, which is
> > > not the case of printf.
> > >
> > > Cheers,
> > >
> > > Jorge
> > >
> > >
> > > On 9/11/07, kashin Lin < kashin08 at gmail.com> wrote:
> > >
> > > > i build okl4 for my pxa270 develop board and upload the image on it.
> > > > but the ouput messages just stop appearing as following:
> > > >
> > > > *OKL4 - (provider: Open Kernel Labs) built on Sep 4 2007 03:31:16
> > > > using gcc version 3.4.4.
> > > > init_spaceids:125: Init spaceids 256 spaces
> > > >
> > > > *****************************************
> > > > * Iguana system, Copyright 1996-2006 *
> > > > * ERTOS - National ICT Australia *
> > > > *****************************************
> > > >
> > > > vbase is 0x1302000, vend is 0xcfffffff
> > > > addr is 0x1302000, vbase is 0x1302000
> > > > PXA25X OS Timer driver starting...
> > > > PXA25X wrap handler installed
> > > > Using FFUART.
> > > > Backed PXA serial*
> > > >
> > > > the stop timming seems to be at the beginning of Wombat which
> > > > use "printk" as it output function.
> > > > ( the function for ouputing the message i got (above) seems to be
> > > > "printf" ).
> > > >
> > > > so i think there are two posible causes:
> > > > 1. "prink" use the different way to ouput (comparing to "printf"
> > > > )or
> > > >     Wombat re-configure UART, so the full system is working but
> > > >     i can't see the ouput messages.
> > > >    ( the required setting to connect my develop board by RS232 is
> > > > 9600 8 n 1)
> > > >
> > > > 2. the system is really stopping due to some reasons...
> > > >
> > > > so how can i recognize which one is the actual cause of this
> > > > situation?
> > > > will option 1 occur?
> > > > (i'm not sure the difference between printk & printf's
> > > > implementation )
> > > >
> > > > _______________________________________________
> > > > Developer mailing list
> > > > Developer at okl4.org
> > > > https://lists.okl4.org/mailman/listinfo/developer
> > > >
> > > >
> > >
> >
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.okl4.org/pipermail/developer/attachments/20070913/035fec72/attachment.htm