[coreboot] [USBOPTIONROM] Turn Real Mode to PM mode

Kevin O'Connor kevin at koconnor.net
Fri May 22 02:46:34 CEST 2009

On Fri, May 22, 2009 at 01:11:14AM +0800, Jason Wang wrote:
> Hi all,
>      I am trying to make optionrom can be run in PM 32 bit mode, and my work
> flow is  1)load gdt 2)open A20 3) set cro bit 4) take the long jump to 32
> bit PM. After step 3) optionrom has already in 16bit PM,but the long jump
> did not work, which should run in to 32bit PM. I paste the whole assemble
> file here. Is there any one who can give  a hand about this?

You can look at how SeaBIOS does it:



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