mismatch between FACP and chipset spec

[Andriy Gapon]

on 28/02/2008 11:52 Rui Paulo said the following:
> On Thu, Feb 28, 2008 at 8:25 AM, Andriy Gapon <avg at icyb.net.ua> wrote:
>>  As some of you probably already know I have a motherboard based on
>>  440BX/PIIX4E chipset:
>>  http://www.geocities.com/SiliconValley/3686/delta_mp2.html
>>
>>  Here's some info from ACPI tables:
>>         PM1a_EVT_BLK=0x4000-0x4003
>>         PM1a_CNT_BLK=0x4040-0x4041
>>         PM_TMR_BLK=0x4008-0x400b
>>
>>  I know that in my case 0x4000 is a base address of "Power Management IO
>>  Space" (as defined by PIIX4 specification).
>>  I see that descriptions of the registers and their bits match between
>>  ACPI specification and PIIX4 specification for registers in PM1a_EVT_BLK
>>  (PMSTS and PMEN registers in PIIX4 parlance) and PM_TMR_BLK (PMTMP
>>  register in PIIX4 parlance).
>>  But addresses given for PM1a_CNT_BLK are not documented at all! On the
>>  other hand ACPI description of that register perfectly matches
>>  description of PIIX4 PMCNTRL register that is located at 0x4004 with a
>>  given base address. So, this is 0x4040 vs. 0x4004, looks like a possible
>>  typo/mistake by an author of ACPI tables for this motherboard.
>>
>>  Question: is there any way I can way override the address of
>>  PM1a_CNT_BLK? My guess is that there is zero chance that there would be
>>  any BIOS updates for this old and exotic motherboard (MP2-BX-X).
> 
> Try dumping your ACPI tables, change the address and load the new
> tables on boot,
> http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/acpi-debug.html

I have some experience with that (and I've been planning to share it for
several years now).
My impression that only DSDT can be changed this way, not the fixed
tables. I could be wrong.


-- 
Andriy Gapon