2.6.18 - AHCI detection pauses excessively

["Berck E. Nash" <flyboy@gmail.com>]

AHCI pauses heartily on during detection boot, but eventually proceeds. 
  I've mentioned the problem before, but have since narrowed it down a 
bit.  The problem does not occur in 2.6.17.3, but does occur in 2.6.18. 
  The problem is still occurring both in 2.6.19-rc5 as well as 
2.6.19-rc5-mm1.

Please cc me on replies since I am not subscribed to LKML.

Messages surrounding the hang:

scsi2 : ahci
ata2: SATA link up 3.0 Gbps (SStatus 123 SControl 300)
ata2.00: qc timeout (cmd 0xec)
ata2.00: failed to IDENTIFY (I/O error, err_mask=0x104)
ata2: port is slow to respond, please be patient (Status 0x80)
ata2: port failed to respond (30 secs, Status 0x80)
ata2: COMRESET failed (device not ready)
ata2: hardreset failed, retrying in 5 secs
ata2: SATA link up 3.0 Gbps (SStatus 123 SControl 300)
ata2.00: ATA-6, max UDMA/133, 640 sectors: LBA
ata2.00: ata2: dev 0 multi count 1
ata2.00: configured for UDMA/133

I should note that on this system ata1 and ata3 both detect quickly, but 
they have 1.5 Gbps devices whereas ata2 has a 3.0Gbps device.

The device:
00:1f.2 SATA controller: Intel Corporation 82801GR/GH (ICH7 Family) 
Serial ATA Storage Controller AHCI (rev 01) (prog-if 01 [AHCI 1.0])
         Subsystem: ASUSTeK Computer Inc. Unknown device 2606
         Flags: bus master, 66MHz, medium devsel, latency 0, IRQ 50
         I/O ports at e400 [size=8]
         I/O ports at e080 [size=4]
         I/O ports at e000 [size=8]
         I/O ports at dc00 [size=4]
         I/O ports at d880 [size=16]
         Memory at febfb800 (32-bit, non-prefetchable) [size=1K]
         Capabilities: <access denied>

dmesg snip from 2.6.17.3, without the hangup:

scsi1 : ahci
ata2: port reset, p_is 40000001 is 2 pis 0 cmd 4017 tf 451 ss 123 se 0
ata2: SATA link up 3.0 Gbps (SStatus 123)
ata2: dev 0 cfg 49:2f00 82:0068 83:5060 84:4000 85:0000 86:1000 87:4000 
88:407f
ata2: dev 0 ATA-6, max UDMA/133, 640 sectors: LBA
ata2: dev 0 configured for UDMA/133


Thanks,
Berck