It has been a few days now that I was seeing a message "ACPI get timing mode failed" while I was booting Arch Linux. Today I found a little spare time to work in. The message appeared after upgrading my kernel to 3.6. The result of this message was that my CD/DVD ROM drive had stopped working.
This is the complete message from dmesg | grep -i ata
ata8: ACPI get timing mode failed (AE 0x300b)ata8: prereset failed (errno=-19)ata8: reset failed, giving up
And this is the output of lspci | grep -i ata
00:1f.2 IDE interface: Intel Corporation 82801IR/IO/IH (ICH9R/DO/DH) 4 port SATA Controller [IDE mode] (rev 02)00:1f.5 IDE interface: Intel Corporation 82801I (ICH9 Family) 2 port SATA Controller [IDE mode] (rev 02)03:00.0 SATA controller: JMicron Technology Corp. JMB363 SATA/IDE Controller (rev 02)03:00.1 IDE interface: JMicron Technology Corp. JMB363 SATA/IDE Controller (rev 02)
The problem had to do with the pata_acpi module. To prevent kernel from loading this module just add modprobe.blacklist=pata_acpi as kernel boot parameter. I am using the old grub so I had to edit /boot/grub/menu.lst and add modprobe.blacklist=pata_acpi at the end of the kernel line. Reboot and that's it. My CD/DVD Rom was working and the error message is gone. Instead I see the normal output in dmesg
pata_jmicron 0000:03:00.1: enabling device (0000 -> 0001)pata_jmicron 0000:03:00.1: setting latency timer to 64