* Christian Sühs chris@suehsi.de [060427 10:57]:
0xc0000 - 0xfffff is normaly Cached?
you can often decide about this in the bios options. which makes little sense, except you plan to rub your nose permanently on an old rom chip.
Means, should I set the cache bit?
You might, if you plan to put something there that should be readable later (and is read a lot of times). So if you are planning to use Linux you don't need to care.
How is the range 640k-1MB normally set in other systems.
0xe0000-0xfffff is always "cached" in awkward bios, as they uncompress parts of their code to those memory adresses where it stays for "bios callbacks". We don't have that, so its not an issue.
You might want to play with this again if you switch CONFIG_COMPRESS on but want the pirq table in 0xf0000-0xfffff without failing.
I would like to set the magic bit for vga to 00 (at the moment it is set for 4K I/O range and all vga instructions are enabled)
run lspci -xxx on LinuxBIOS and factory BIOS and start comparing the differences, or start looking in the datasheets for it..
Stefan