My ASUS M4A87TD EVO board has two on-board disk controllers, one of them is a JMicron JMB361 with one old IDE disk connected. When I boot Arch Linux, it shows in the system journal like this:
Nov 02 12:53:50 host kernel: ahci 0000:04:00.0: JMB361 has only one port
Nov 02 12:53:50 host kernel: ahci 0000:04:00.0: AHCI 0001.0000 32 slots 2 ports 3 Gbps 0x3 impl SATA mode
Nov 02 12:53:50 host kernel: ahci 0000:04:00.0: flags: 64bit ncq pm led clo pmp pio slum part
Nov 02 12:53:50 host kernel: ata9: SATA max UDMA/133 abar m8192@0xfbffe000 port 0xfbffe100 irq 17
Nov 02 12:53:50 host kernel: ata10: SATA max UDMA/133 abar m8192@0xfbffe000 port 0xfbffe180 irq 17
Nov 02 12:53:50 host kernel: ata9: SATA link down (SStatus 0 SControl 300)
Nov 02 12:53:50 host kernel: ata10: softreset failed (1st FIS failed)
Nov 02 12:53:50 host kernel: ata10: softreset failed (1st FIS failed)
Nov 02 12:53:50 host kernel: ata10: softreset failed (1st FIS failed)
Nov 02 12:53:50 host kernel: ata10: limiting SATA link speed to 1.5 Gbps
Nov 02 12:53:50 host kernel: ata10: softreset failed (1st FIS failed)
Nov 02 12:53:50 host kernel: ata10: reset failed, giving up
I don't know where devices ata9 and ata10 come from. There is only one IDE disk connected to that controller and it is initialized properly. The BIOS does not show anything relating to ata9 or ata10 (and it shouldn't because there is nothing connected there) and I haven't found any way to disable them in the BIOS.
I thought I had found a way to disable detection of these two devices here: How to tell Linux Kernel > 3.0 to completely ignore a failing disk? but it hasn't made any difference. This is how I am booting the kernel:
Nov 02 12:53:50 host kernel: Linux version 3.17.2-1-ARCH (builduser@thomas) (gcc version 4.9.1 20140903 (prerelease) (GCC) ) #1 SMP PREEMPT Thu Oct 30 20:49:39 CET 2014
Nov 02 12:53:50 host kernel: Command line: BOOT_IMAGE=/vmlinuz-linux root=UUID=2cfdc373-7023-48d7-a90d-43d030af277b rw libata.force=9:disable,10:disable quiet
The system manages to boot ultimately but the failing softresets annoyingly delay the boot process by at least 90 seconds.