[SeaBIOS] [Qemu-devel] [RFC] Passing boot order from qemu to seabios

H. Peter Anvin hpa at zytor.com
Wed Oct 13 22:22:25 CEST 2010

On 10/13/2010 01:00 PM, H. Peter Anvin wrote:
> On 10/13/2010 12:17 PM, H. Peter Anvin wrote:
>> The ACPI specification recognizes three interfaces as standard: PC/AT
>> (64 bytes, even though 128 bytes is available on a lot of platforms),
>> PIIX4 (256 bytes), and Dallas Semiconductor ("256 bytes or more").  The
>> interface for the latter isn't well cited in the ACPI spec, but I'm
>> guessing this is referring to the DS17885 series of chips, which can
>> have up to 8K CMOS using a bank-switched scheme which presents 128 bytes
>> at a time (thus accessible via only the standard 70/71 ports.)
> FWIW, the DS17885 scheme actually allows addressing up to 64K; 8K is the
> maximum that DS produced with this particular interface as far as I
> know, but there are 16 address bits available.
> 	-hpa

I think this is the relevant application note:



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