[coreboot] (GSoC__SCSI boot)GSOC Midterm survey and new problem(Vendor ID mismatch)
zrfail at gmail.com
Mon Jul 14 17:21:47 CEST 2008
2008/7/14, Kevin O'Connor <kevin at koconnor.net>:
> Right - seabios needs to be using its stack in order to call 16bit
> functions. You probably need to save and restore the stack.
> Completely untested, but something like:
> movl %esp, %esi
> movl $BUILD_STACK_ADDR, %esp
> ljmp 0x10, $1f
> calll post_coreboot
> movl %esi, %esp
I used this:
"movl %esp, %esi\n"
"movl $" __stringify(BUILD_STACK_ADDR) ", %esp\n"
"ljmp $0x10, $post_coreboot\n"
and added this at the end of post_coreboot() function:
"movl %esi, %esp\n"
Then it can return to coreboot correctly. Till the payload(I used no
But pci_dev_init() is executed more than one time so vga is
initialized more than one time in SeaBIOS. A flag variable would be
used to run SeaBIOS only once.
> However, note that the above wont save/restore the idt/gdt. And
> again, I'm not sure if coreboot puts its stack/idt/gdt somewhere where
> seabios may overwrite it.
I am supprised that it just run correctly when return address is set.
I supposed to restore the gdt. Maybe the gdt of SeaBIOS and coreboot
are the same.
And I want to know where will SeaBIOS write in the memory. Such as the
range of bda and ebda?
I think it is time to int SCSI controller, and set the int 13 for it.
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