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FIXED: no /proc/acpi, trying to dump dsdt to a file

PATCH glen martin 1 participant 1 message Mar 30, 2006 ACPI

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Or at least, I'm past my pain, thanks to a lot of help from Robert and Len.

To recap:

The DSDT in my BIOS was very broken, such that ACPI didn't load up properly. This meant I was having trouble reading the data from my BIOS using /proc/acpi/dsdt.

To fix this, I applied this patch to the kernel (which was 2.6.15):
https://bugzilla.novell.com/show_bug.cgi?id=147621#c22
Rebuild, reboot, and I could get at the dsdt data at /proc/acpi/dsdt.

Then iasl couldn't handle the extracted data, because it failed error checking in the same way the kernel had. Patch it like this:
<snip>

nssearch.c 2006-03-29 12:11:22.000000000 -0800 renamed from nssearch.c.~1~ 2006-03-29 18:22:16.000000000 -0800 +1 -1
@@ -403,7 +403,7 @@
    {
        ACPI_ERROR ((AE_INFO, "Bad character in ACPI Name: %X",
            TargetName));
-        return_ACPI_STATUS (AE_BAD_CHARACTER);
+//        return_ACPI_STATUS (AE_BAD_CHARACTER);
    }
 
    /* Try to find the name in the namespace level specified by the 

caller */
</p>

This allowed iasl to function on the extracted dsdt data.

There remained some errors in the extracted dsdt that I'm still looking at.

In a side conversation, though, I had another look at a supposedly working cleaned-up version of the DSDT for my machine that I downloaded from http://acpi.sourceforge.net/dsdt/view.php. I'd tried to assemble it using iasl on Linux, which segfaulted on this file. This was why I started down this path of extracting my existing DSDT. But Robert had the idea to try it using the Windows binary iasl, and it assembled fine there. I was able to take that binary and load it into my kernel using the initramfs dsdt patch here:
http://gaugusch.at/kernel.shtml.

I wasn't already using an initramfs, so not knowing how, on a lark I constructed a bogus one:
mkdir temp
cp /path/to/my_dsdt.asl temp/DSDT.asl // this filename matters
cd temp
find . | cpio --quiet -o -H newc | gzip -9 > ../minirt.gz
cd ..
rm -r temp
This initramfs is likely bogus, but it worked anyway for this purpose. Just add it to your grub.conf in an initrd line.

The reward? Now my onboad LAN interface is working, so I can retire the add-on board I installed to get by with. Not that geeks like me need a reward.

Hope this recap helps someone. And thanks once again to Robert and Len for their help.

glen