[U-Boot-Users] disabling d-cache in 'bootelf' for QNX

[Stefan Roese <sr@denx.de>]

Hi Matthias,

On Monday 07 January 2008, Matthias Fuchs wrote:
> there is a simple approach to disable dcaching on 440 used for the 440 usb
> code (cpu/ppc4xx/usb.c). The code is used to disable dcaching before
> starting the USB subsystem. It updates the tlb entry. But it is not
> complete working. Disbling works, but reenabling (via 'usb stop') does not
> work.

Right. It would really be great if somebody could take a look at this issue. 
Since this is the last showstopper to enable cache (I & D) on 440 platforms.

> But with CONFIG_4xx_DCACHE enabled this at least allows you to use 
> USB but with disabled dcache from that moment on.
>
> Perhaps it is possible to move the change_tlb() call into the
> dcache_disable when it is working sometime.

Yes, this is the plan. When it is finally working completely, the "normal" 
cache functions should be supported for 440 too.

Thanks.

Best regards,
Stefan

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