[U-Boot-Users] UNCACHED_SDRAM macro issue

[Luigi 'Comio' Mantellini]

Hi Shinya,

see inline.

On gio, 2008-02-14 at 12:55 +0900, Shinya Kuribayashi wrote:
> Luigi 'Comio' Mantellini wrote:
...
> 
> So it seems Alchemy-based SoC. if so,
> 

No. I'm working on a SoC that uses a IP core from MIPS (mips4kec). The
mips core should be (formally) a standard mips core.

> > What I need to change on my board specific u-boot in order to use the
> > KSEG1 address space?
> 
> what do you mean "in order to use the KSEG1 address space?" I'm not
> familiar with Au1XXX, but you might need CONFIG_AU1X00 in your board
> config. Some URLs added[1][2].
> 

The CONFIG_AU1X00 doesn't work for me. from datasheet there aren't
differences between my SoC and the standalone mips4kec. This is the
memory map how depicted by the datasheet:

0x00000000--0x7fffffff KUser - Cached / Mapped
0x80000000--0x9fffffff KSEG0 - Cached / Unmapped
0xA0000000--0x9fffffff KSEG1 - Uncached / Unmapped
....

I think that on my application the UNCACHED_SDRAM should map the address
on KSEG1 (how it is now) but this simply doesn't work. Instead, using
the PHYSADDR(a) macro... the kernel is able to start.

I suspect that there are issues on cache management. Can be? 

Thanks a lot,

luigi

>   Shinya
> 
> [1] http://thread.gmane.org/gmane.comp.boot-loaders.u-boot/32316/focus=32372
> [2] http://www.linux-mips.org/wiki/Alchemy
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