[SeaBIOS] Help with 16bit and 32bitFlat

Kevin O'Connor kevin at koconnor.net
Thu Oct 20 14:46:47 CEST 2011


On Thu, Oct 20, 2011 at 11:44:50AM +0200, Gerd Hoffmann wrote:
> >> The ahci driver has to access some memory addresses above 1 meg to
> >> work properly and so it uses the pci_readl/writel() functions which
> >> trampoline to/from 32bit mode to acomplish this.  If you need to do
> >> something similar, you could use that as a model.
> 
> Another option would be to have the int15 handler trampoline to 32bit
> mode before calling process_op.

I assume you mean int13 (disk access).  The trouble with doing this is
it would break any code that calls int13 in vm86 mode.  Granted,
anything using AHCI would already not work in this mode, but it's a
leap to restrict this for all disk access.

-Kevin



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