[SeaBIOS] ohci bulk?

Kevin O'Connor kevin at koconnor.net
Sat Nov 20 19:05:21 CET 2010


On Sat, Nov 20, 2010 at 12:58:56PM -0500, Stefan Berger wrote:
> On 11/20/2010 12:50 PM, Kevin O'Connor wrote:
> >I suppose one could implement a simple SMM gateway - write a magic IO
> >bit to invoke the SMM handler, have the SMM handler backup the cpu
> >state somewhere in BIOS owned memory, and then leave SMM mode with
> >execution at a BIOS handler running in 32bit flat mode.  The BIOS
> >handler could then do its work and manually return the CPU to its
> >initial state before returning to the guest.  The BIOS would need to
> >ensure that it didn't allow interrupts (or NMIs) while in this mode,
> >but that's possible.  One would probably want to ensure that the BIOS
> >didn't touch any non-BIOS owned memory in this state as well, but
> >that's also possible.
> >
> FWIW, I am currently working on a gateway for calling 32 bit
> functions in the relocated 32bit code from 16 bit code, opening up
> that are for more than the init functions. It works fine from what I
> can see also considering the mixture of register and stack passing
> of arguments. Would that be helpful here?

Is it something like stacks.c:call32() or is it via SMM?

BTW, are you reserving the relocated code or are you only doing this
during the init phase?

-Kevin



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