Re: aranym vs atafb

[Petr Stehlik <pstehlik@sophics.cz>]

Michael Schmitz píše v Pá 28. 12. 2007 v 04:09 +0100:

> That does probably steal our precious ST-RAM space.
> 
> I guess I'll have to just allocate the required ST-RAM for atafb early

Look at this:

64 MB of FastRAM:
  Memory: 68184k/68252k available (1956k kernel code, 9568k data, 100k
init)
  atafb: screen_base 00680000 real_screen_base 00680000 screen_len
311296

128 MB: screen_base 00b00000
192 MB: screen_base 01700000
256 MB: screen_base 01600000

So the question is how the atafb decides where to put the videoram and
why is it related to FastRAM size...

BTW, by further playing with the -F parameter of ARAnyM I've noticed
that if the total RAM is <= 64 MB (i.e. FastRAM is <= 50 MB) then the
screen_base is at 0x600000 but as soon as total RAM is 65 MB the
screen_base moves up by 0x080000. And when it hits 108 MB of total RAM
it moves the screen_base up by another 0x080000 (to 0x700000). So there
seems to be a "clever" algorithm somewhere in atafb that was not tested
for real large FastRAM sizes?

Petr