Re: Porting NetBSD to the Zipit Z2 XScale handheld

[Robert Swindells <rjs%fdy2.co.uk@localhost>]

"lausgans%gmail.com@localhost" <lausgans%gmail.com@localhost> wrote:
>I'm interested in porting NetBSD to the Zipit Z2 clamshell device
>(poor-man's analog of Sharp Zaurus).
>Here are the specs: http://linux.zipitwireless.com/wiki/Z2
>Originally it comes with bootloader called blob:
>http://linux.zipitwireless.com/projects/z2kernel (was it used to load
>NetBSD kernel ever?) and runs cutted Linux-based firmware.
>Anyway, the blob is pretty limited and can't even load kernels from an
>external SD card:
>http://zipitfan.wordpress.com/2011/02/02/z2-bootloaders/ so the port
>of U-Boot loader was unrolled which raised the availability of many
>Linux distros for the device. It meant to be flashed in place of the
>stock loader.

Ok.

>Now, what is the most appropriate existing arm port to start with? I'm
>seeing the only ports that include PXA270 support are evbarm, hpcarm
>and zaurus. I suppose the relevant among them are hpcarm and zaurus,
>as evbarm has nothing about mobile device periphery like lcd and
>keyboard. However, evbarm has U-Boot image rules in makefiles for some
>machines it covers.

Put it in evbarm.

>So i've started by rewriting init files from the hpcarm's WZERO3 and
>producing uimg like in evbarm. However U-Boot rejects to load the
>final image with address/instruction related errors. What addresses
>should i use? The ones used to load Linux kernels don't work as well
>as those which are used for machines in evbarm port.

U-boot works with physical addresses, you need to load the image
at a different address to the one specified as the location for
the kernel, it will then be copied to the correct address.

In your mk.zipit use:

KERNEL_BASE_PHYS?=0xa0008000
KERNEL_BASE_VIRT?=0xc0008000

Robert Swindells