[coreboot] ACPI S3

ron minnich rminnich at gmail.com
Mon Nov 24 18:09:46 CET 2008

On Sun, Nov 23, 2008 at 11:02 PM, Feng, Libo <Libo.Feng at amd.com> wrote:
> Hi, All,
> I am still trying to implement the S3 state in dbm690t. Now I can jump into the waking vector code running under the real mode. However, the code contains some 32bit instructions, when these instructions are executed, the system always hangs, for the processor thought they were of 16bit. Please see the code in the below link.
> http://lxr.linux.no/linux+v2.6.18/arch/x86_64/kernel/acpi/wakeup.S
> In 37 and 38 line, there are two 32bit instructions,
> 66 6a 00   pushl   $0  # Kill any dangerous flags
> 66 9d        popfl
> You can see the machine codes starting with 0x66 indicating these 32bit instructions. However, processor always thought these were of 16bit, so, instructions are changed into:
> 66 6a         push byte 00h
> 00 66 9d     add [bp-63h], ah

what could explain this is that you are not in 16-bit mode, you are
actually in 32-bit mode for some reason. The 66 will then run these
instructions in 16 bit. That is just a guess.

Are you certain you are in 16 bit mode?


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