Rockbox.org home
release
dev builds
extras
themes manual
wiki
device status forums
mailing lists
IRC bugs
patches
dev guide



Rockbox mail archive

Subject: Re: X5 dual boot

Re: X5 dual boot

From: Linus Nielsen Feltzing <linus_at_haxx.se>
Date: 2006-05-02

RaeNye wrote:
> Cowon wrote both the preloader and the OF, so they rely on each other in
> many ways
> (some less predictable than others, e.g., using the byte at 0x30000000 to
> signal RTC alarm or just leaving the IDEConfig registers in a certain state)
> My aim in writing a dual-bootloader is to decide as quickly as possible if
> OF is to be loaded and only afterwards to setup registers for RB.
> Some of the registers even stay in their default settings (which are unknown
> to me).

I just think that we'd be better off if we used our own code instead of
relying on the Cowon binary. Especially since we want the firmware
patcher to be independent of the Cowon firmware/bootloader versions.

> You could also say that it doesn't matter since you only transfer a few
> bytes, but the point is that RB's pcf50606 functions aren't better than the
> OF's.

No, they may not be "better". But they work. And the source code is
there for you to enhance.

> Again I think it's a don't-burden-cpu-for-no-reason thing. DMA is there for
> a reason; let the CPU spend its cycles in SWCODEC (or GUI, whatever).

Sure. Go ahead.

Linus
Received on Tue May 2 19:13:02 2006


Page was last modified "Jan 10 2012" The Rockbox Crew
aaa