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Re: Help with booting Linux off my Redboot prompt

Albert was correct - thanks Albert!

For the list, here is the deal.

the IXP425 has two UARTs - the first is called the high speed UART and the second is called the Console UART

The high speed UART is /dev/ttyS0 and the Console UART is /dev/ttyS1

Hope this helps for future reference

Krishna

----- Original Message ----- From: "Krishna Ganugapati" <krishnag@marakicorp.com>
To: "Alfred Wong" <alfred.wong80@gmail.com>
Cc: "Nickolay" <nickolay@protei.ru>; <ecos-discuss@ecos.sourceware.org>
Sent: Tuesday, February 22, 2005 10:26 PM
Subject: Re: [ECOS] Help with booting Linux off my Redboot prompt


Thanks I'll try this. A couple of questions

a) How does the kernel know where to find the rootfs - is it preconfigured and if so can someone tell me where that information is located

b) How does the exec know that the kernel is loaded at 0x01600000? Internally, I've found that there is a ecos setting that defines where the kernel is supposed to be executed from 0x00600000.

I do understand that exec takes in parameters where you can specify the physical address of where zImage is loaded and the length of zImage and physical address of the initrd, but in the absence of providing these parameters how does it work?

c) Can someone provide a tutorial about how redboot "execs" a kernel?

d) A question for Alfred: I would think that UART0 is /dev/ttyS1 and UART1 is /dev/ttyS0 - Alfred do you have two UARTs on your board or a single UART - and if so do you have UART1 or UART0 enabled... I set mine to /dev/ttyS0 because I'm using UART0 ...

Thanks!

Krishna
----- Original Message ----- From: "Alfred Wong" <alfred.wong80@gmail.com>
To: "Krishna Ganugapati" <krishnag@marakicorp.com>
Cc: "Nickolay" <nickolay@protei.ru>; <ecos-discuss@ecos.sourceware.org>
Sent: Tuesday, February 22, 2005 7:59 PM
Subject: Re: [ECOS] Help with booting Linux off my Redboot prompt


You could try this :
exec -c "console=ttyS1,115200 root=/dev/mtdblock4 rw, mem=64M@0x00000000"

works for me on ixp425 based board.

Cheers,
Alfred



On Tue, 22 Feb 2005 09:56:06 -0800, Krishna Ganugapati
<krishnag@marakicorp.com> wrote:
Thanks Nickolay

I did specify all four parameters to "exec" and while things do not dump
core or anything -- it looks like its hanging somewhere in the Linux
startup. I understand this may be the wrong place to pose the question, but
has anyone used the BDI2000 to debug a Linux target after it has been
invoked from Redboot using exec.

The BDI2000 documentation is pretty sparse.

I also discovered that the base address for the IXDP425 is 0x00600000 after
greping through the sources.

My board only has UART 0 and I'm suspecting that it has something to do with
how the Linux console works. I get no output to my console window once I
invoke exec...

I need to figure out how to debug a Linux target under Redboot using a
BDI2000

Thanks

Krishna

----- Original Message -----
From: "Nickolay" <nickolay@protei.ru>
To: "Krishna Ganugapati" <krishnag@marakicorp.com>
Cc: <ecos-discuss@ecos.sourceware.org>
Sent: Tuesday, February 22, 2005 3:18 AM
Subject: Re: [ECOS] Help with booting Linux off my Redboot prompt

> Krishna Ganugapati wrote:
>
>> I have successfully built redboot for my IXP425 - can load redboot >> image
>> store it in flash, npe's work fine and I can successfully tftp images
>> down to my board from by RedHat9 Linux box.
>>
>> I've built Linux kernels and a rootfs.
>>
>> My compressed Linux kernel is zImage
>>
>> and my compressed rootfs is rootfs.gz
>>
>> I execute the following commands at my Redboot console
>>
>> a) load -r -v -b 0x00800000 rootfs.gz ; load the rootfs.gz image @
>> 0x0800000
>>
>> b) load -r -v -v 0x01600000 zImage ; load the compressed kernel >> zImage
>> @ 0x01600000
>>
>> c) exec
>>
>> The resulting output is
>> Using base address 0x01600000 and length 0x000b73c0 (which is the >> correct
>> size of the image)
>>
>> However following that, I get nothing....
>>
>> Any ideas how I can debug further... or should I be taking this to
>> another alias...
>>
>>
>> Thanks!
>>
>> Krishna
>
> Try explicitly indicate what you want load from.
> exec -b 0x01600000 -l 0 0x01600000
>
>
>
> --
> Before posting, please read the FAQ: > http://ecos.sourceware.org/fom/ecos
> and search the list archive: > http://ecos.sourceware.org/ml/ecos-discuss
>

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and search the list archive: http://ecos.sourceware.org/ml/ecos-discuss




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and search the list archive: http://ecos.sourceware.org/ml/ecos-discuss

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