Footbridge / 21285 phsical/virtual address selection patch

Hello

I've got my hands on a weird-ish ARM board with an SA-110 and a 21285 footbridge. It is NOT the EBSA285 (it actually used to be a Quantum netdisk NAS) but it is close and I have the kernel configured in "EBSA285 Host" mode because it is close enough. (I had to comment out a beq instruction in the platform checker to get the kernel to boot on this board).

Well...

I've run into some issues. The MMU code seems broken somewhere, and the kernel only works for me in NOMMU mode. However, in the (MM)I/O address mapping for the 21285 driver, the footbridge code completely ignores CONFIG_MMU and has all the I/O addresses #defined as if they were all virtual. This is obviously not going to work if the MMU is disabled and all the addresses will be wrong.

I've attached a patch (-p0) that adds an #ifdef to select between physical and virtual addresses for the 21285 chip, depending on CONFIG_MMU. I do not have a real EBSA285 to test this on, but this board does have a real 21285 and it is working for me.

I've run into some additional problems, specifically with the uart driver, but I will prepare some of those patches in a bit.

What do you guys think?

Thanks
Steve
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I don't believe you. I've been booting kernels on the Netwinder and EBSA285 platforms (with varing amounts of success because of IDE/PATA issues.) Nothing fundamental, just plain buggy storage driver issues.