Assembler coding help needed. [solved, patch enclosed]
jhb at FreeBSD.org
Mon Jan 12 12:56:25 PST 2004
On Sunday 11 January 2004 04:39 pm, Martin Nilsson wrote:
> Marcin Dalecki wrote:
> > Martin Nilsson wrote:
> >> I'm trying to find out why I can't boot 5.2 from USB CDROM on
> >> Supermicro motherboards. (I have an old Gateway P3 that can!).
> >> I've found out that that only 0x20 of 0x4c sectors of the loader are
> >> read in and it therfor traps when executed. (read is only called once).
> >> load_notrunc: sub %dh,%cl # Update count
> >> push %eax # Save
> >> call read # Read it in
> > The fun will be ^^^^ here. The rest is self contained and
> > doesn't depend on CPU variant or periphery.
> I found the problem!
> The bios trashes %cx when reading from USB CD but not when reading from
> ATAPI CD.
> The attached patch fixes this and two other small nits in
Thanks for the nit fixes.
> Can somebody (jhb) commit this?
> This probably affects all Phoenix-Award bios equipped boxes. My old
> Gateway with AMI BIOS works as it should.
I will commit something similar. I will save %cx around the BIOS call itself
in the read function.
John Baldwin <jhb at FreeBSD.org> <>< http://www.FreeBSD.org/~jhb/
"Power Users Use the Power to Serve" = http://www.FreeBSD.org
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