EPIA Linuxbios strangeness

Steve Gehlbach steve at nexpath.com
Sun Aug 17 15:57:01 CEST 2003


SONE Takeshi wrote:

> Setting bit 1 of ISA bridge register 4F does a system reset.
> I have these lines instead of /sbin/reboot in /etc/init.d/reboot
> (Debian system).
> 
>     sleep 1
>     setpci -s 0:11.0 4f.b=9
> 

 From the datasheet:

Via VT8231 fn 0
Offset 4F –PCI Bus and CPU Interface Control ..........RW
----------------------------------------------------------

7-4 Reserved ................always reads 0
3 CPU Reset Source
   0 Use CPURST as CPU Reset..default
   1 Use INIT# as CPU Reset
2 Config Command Reg Rx04 Access (Test Only)
   0 Normal:Bits 0-1=RO,Bit 3=RW...default
   1 Test Mode:Bits 0-1=RW,Bit-3=RO
1 IRDY #Wait States
   0 0 Wait States.............default
   1 1 WaitState
0 Software PCI Reset ...write 1 to generate PCI reset

What about the ACPI I/O space (set same as Award BIOS, I think, 0x4000), 
in particular 0x4002, 0x4003? Anyway this can be used?

-Steve




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