[embedded platform] kernel questions

Hello,

I'm in for a porting Linux on ARM926EJ-S based System-on-Chip running at

216MHz. Only uCos has been ported on the board so far (not by me).

This is my first experience of Linux porting, so I found a few articles on the Web to read up. Right now I want to clear a few major questions:

- what kernel version to choose. I understand it depends on system requirements and hardware specs, and I think 2.6.x branch should be given a preference, as it supports a lot more hardware then 2.4 and community provides better support as well :) Question is what version of

2.6.x family to choose, is there a strict criterion to choose ?

- what bootloader can you recommend to choose for porting on the board? There are U-boot, Redboot and ARMboot as the most common and portable. I briefly check the Web Links and found that only U-Boot supports ARM9, am I right?

- I mentioned above about uCos - is it reasonable trying to port uCos device drivers on to the Linux platform, or drivers should be rewritten from scratch, as uCos and Linux architectures I guess are quite different ?

Thanks in advance and looking forward to getting answers to my queries!

With best regards, Roman Mashak. E-mail: snipped-for-privacy@tusur.ru

I'm always working with the vanilla kernel. Don't know if it is the best way. Sometimes its easier to start with a vanilla kernel, and to add some patches specific to your hardware. Sometimes its easier to start with sources the manufacturer provides. It depends on your hardware and requirements.

There are various ready-to-use binary ARM toolchains around. So it should be easy to find one that is working for you.

jbe

Hello, Juergen! You wrote on Fri, 15 Aug 2008 17:14:30 +0200:

??>> Question is what version of ??>> 2.6.x family to choose, is there a strict criterion to choose ?

JB> For new hardware always start with the most recent kernel. And as long JB> development is going on, continue to use the next recent kernel if it JB> gets released.

Is it sensible to take vanilla kernel from ftp.kernel.org and start with this or there're seperate branches with ARM-specific patches, which might be more reasonable to use?

And one question on toolchains. The chip-maker doesn't provide any Linux-based toolchain. Does it make sense to spend time (and I'm pretty sure building crosstools may consume lots of weeks) to prepare our own tools or to pick out the pre-built one?

Thanks.

With best regards, Roman Mashak. E-mail: snipped-for-privacy@tusur.ru

Hello, Juergen! You wrote on Sat, 16 Aug 2008 09:37:59 +0200:

[skip] Thanks for your comments.

??>> And one question on toolchains. The chip-maker doesn't provide any ??>> Linux-based toolchain. Does it make sense to spend time (and I'm ??>> pretty sure building crosstools may consume lots of weeks) to prepare ??>> our own tools or to pick out the pre-built one?

JB> There are various ready-to-use binary ARM toolchains around. So it JB> should be easy to find one that is working for you. I searched, but found only papers describing building crosstools yourself. Can you recommend any sites offering pre-build toolchains?

With best regards, Roman Mashak. E-mail: snipped-for-privacy@tusur.ru

I simply tried google with "ARM toolchain" and found many toolchains. For example "

" and many other.

jbe

A simple ARM v4 or ARM v5 core toolchain should help you. You don't need a specific arm926ejs toolchain.

jbe

Please check this link

I hope this help, /roberto

Hello, Juergen! You wrote on Mon, 18 Aug 2008 20:17:08 +0200:

[skip] ??>> I searched, but found only papers describing building crosstools ??>> yourself. Can you recommend any sites offering pre-build toolchains?

JB> I simply tried google with "ARM toolchain" and found many toolchains. JB> For example "

" and many other. I already went through this link. It seems to provide bare-metal only toolchains; crosstools provided by codesourcery.com (there is a lite free-of-charge version) doesn't support arm926ejs. Hence I asked in this group.

With best regards, Roman Mashak. E-mail: snipped-for-privacy@tusur.ru