[coreboot] New patch to review for coreboot: 73b5bba Prepare the BIOS data areas before device init.

Andrew Goodbody ajg4tadpole at gmail.com
Wed Mar 7 13:05:07 CET 2012

On 07/03/12 01:06, Stefan Reinauer (stefan.reinauer at coreboot.org) wrote:
>      NEW/FIXED now reads consistent values:
>      ebda_addr=0xf6000 lowmem=0x100000

OK, now this worries me. Any time you move away from the classic PC 
memory map you are risking problems.

0xe0000-0xfffff would normally be for shadowed firmware.
0xc0000-0xdffff would normally be for option ROMS
0xa0000-0xbffff would normally be for legacy VGA memory

So I would expect to see the EBDA at 0x9c000 for 1KB and hence the top 
of usable real mode memory to be at 0x9ffff. Now I may be speaking out 
of turn as I have no idea how coreboot organises its memory map or how 
that relates to SeaBIOS etc. but unless you can guarantee that no 
software that will run on this machine will be upset by your values I 
would suggest sticking with the classic legacy values instead.


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