little kernel question

Francois-Rene Rideau fare@tunes.org
Sat Feb 21 22:11:28 CET 2004


On Sat, Feb 21, 2004 at 09:01:26PM +0100, Oleg Gusev wrote:
> arch/arm/mm/init.c reserves memory below TEXTADDR.
> There is also a comment that explains what for.
Oh, this is so evil!

> I vote for character device /proc/driver/fux0red_rtc if you will write it :)
Duh. I refuse to write it.
Completing the 16 bit of milliseconds into 64-bit time is more complexity
than I care to handle, and otherwise it's pretty useless.
Moreover, let's see first if it survives SA-1101 init.

> The most clean way to be polite with wince is to reduce its
> data memory to an absolute minimum, mark the pages it uses
> (i guess they are continuous in physical memory) and transfer this
> info through bootloader parameter (reallykeepwincemem=0xdead,0xbeef)
Nah. The real clean way is to have a hook "restore wince"
that takes a compressed image and does that reverse of hpcbootl:
reassemble a clean working wince image. Ouch. I don't volunteer.
Now, what's wrong with having to remove all batteries (including backup)
when we leave Linux? Linux isn't meant to be left, anyway.
Memory is expensive (at least until you find a way to build memory modules).

> It's at 0xc0000000 offset from SA1101_BASE (i.e. DRAM bank 3),
> but it is a big pain to read from it. IMHO even wince keeps the copy 
> of framebuffer in main RAM (i could not boot after enabling 1024x768 VGA
> output). So, leave it to the sa1101fb driver to take care of that memory
> (once it is written). And it is 1Mx16=2MB RAM, not 1MB.
Hey, that's nice! We could put a ramdisk there :)

> Does blob reset sa1101 ?
No it doesn't.

> IMO, you have put too many 55's.
Well, it's better than the 0s that were there previously.
I just put 100 (AltGr) for the Fn key, too.
Plus it's actually AltGr on my french keyboard.

> The key hangs the machine because the driver itself is a gross hack ;)
Hum. In any case, I don't want to wait till the hack is fixed
so as to have a decent keyboard mapping.

[ François-René ÐVB Rideau | Reflection&Cybernethics | http://fare.tunes.org ]
[  TUNES project for a Free Reflective Computing System  | http://tunes.org  ]
He who refuses to do arithmetic is doomed to talk nonsense.
	-- John McCarthy, in his webpage on Progress and Sustainability


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