Ok put another way: 0xf000 - 0xffff from who's point of view, CPU, PCI bus, or ISA bus?
Ok... I see ipl.S for sis630 does a far call right at the reset_vector: so the i386 switches from the dummy segment descriptor it gets at reset 0xfffff000 to 0xfe00. Sorry kinda thinking outloud here. I think the PIIX4 makes 0xf000-0xffff ram, which the std BIOS shadows itsself into before jumping there, but I'm just guessing. What does the 630 do? ----- Original Message ----- From: "Ronald G Minnich" <[EMAIL PROTECTED]> To: "Jeremy Jackson" <[EMAIL PROTECTED]> Cc: <[EMAIL PROTECTED]> Sent: Wednesday, March 27, 2002 9:08 PM Subject: Re: important changes .... > On Wed, 27 Mar 2002, Jeremy Jackson wrote: > > > Is this before the 1st intersegment call, when the i386 > > forces the upper address lines to 1's? I'm getting close > > to having it all figured out... I have lots of 2-3" thick > > books opened around me. > > > you just lost me ... > > ron >
