ACPI on Dell Optiplex

[Botond]

Hi,
I have a Dell OptiPlex GX240 and I'd like to have ACPI support under FC5. Neither FC5 nor Knoppix do recognize the ACPI system of my machine, but everything (power button, etc.) is working fine under Windows XP.
Here's everything ACPI releated from my dmesg:

DELL GX240 detected: force use of acpi=ht
ACPI: RSDP (v000 DELL                                  ) @ 0x000fd560
ACPI: RSDT (v001 DELL    GX240   0x00000008 ASL  0x00000061) @ 0x000fd574
ACPI: FADT (v001 DELL    GX240   0x00000008 ASL  0x00000061) @ 0x000fd5a8
ACPI: SSDT (v001   DELL    st_ex 0x00001000 MSFT 0x0100000d) @ 0xfffe5f92
ACPI: MADT (v001 DELL    GX240   0x00000008 ASL  0x00000061) @ 0x000fd61c
ACPI: BOOT (v001 DELL    GX240   0x00000008 ASL  0x00000061) @ 0x000fd678
ACPI: DSDT (v001   DELL    dt_ex 0x00001000 MSFT 0x0100000d) @ 0x00000000
ACPI: PM-Timer IO Port: 0x808
ACPI: Local APIC address 0xfee00000
ACPI: LAPIC (acpi_id[0x01] lapic_id[0x00] enabled)
ACPI: LAPIC (acpi_id[0x02] lapic_id[0x01] disabled)
Using ACPI for processor (LAPIC) configuration information
Kernel command line: ro root=LABEL=/ rhgb quiet acpi=noirq
ACPI: Subsystem revision 20060127
ACPI: Interpreter disabled.
pnp: PnP ACPI: disabled
PCI quirk: region 0800-087f claimed by ICH4 ACPI/GPIO/TCO

Was anybody able to bring ACPI to live on a similar system?
My BIOS is A03. Shall I upgrade it to A05?
Thanks for any help.

[r1348]

As long as you keep the acpi=noirq parameter in your kernel boot line, the kernel won't activate acpi for irq assignations. Just modify your kernel boot line in /boot/grub/grub.conf

[Botond]

Regardless if I have "acpi=noirq" or "acpi=on" or no acpi option at all the kernel doesn't enable the ACPI interface (eg. there's no /proc/acpi directory).

[Botond]

In case anybody would be interested the vanilla kernel forces the "acpi=ht" option when it detects a Dell Optiplex GX240. This is a bit strange because my machine doesn't have a HyperThreading processor.
Anyway if I remove the relevant lines from arch/i386/kernel/acpi/boot.c and recompile the kernel ACPI seems to work. So far.