sata slave on intel ICH7

[Dane Miller]

Anyone have thoughts on this?  If I'm missing salient details or posting
to the wrong list, please point me in the right direction.

On Wed, 2008-03-05 at 13:54 -0800, Dane Miller wrote:
> Hi,
> 
> FreeBSD 6.3-RELEASE detects one of my three SATA disks as "ata2-slave".
> I thought SATA did away with the master/slave ugliness of PATA. 
> 
> Thinking maybe this was misleading output from FreeBSD, I did some
> concurrent writes using dd.  Sure enough, I see poor performance on
> concurrent writes to ad4 and ad5 (ata2-master and ata2-slave), while I
> see good performance on concurrent writes to ad4 and ad6 (ata2-master,
> ata3-master).  I can provide more details on the write tests I
> performed, but I'm more interested in *why* FreeBSD detects one of my
> SATA disks as a slave...
> 
> Here are some details:
> 
> 6.3-RELEASE FreeBSD 6.3-RELEASE #0 i386
> Motherboard: Intel S3000AH
> BIOS: SATA Mode is set to "Enhanced" (as opposed to "Legacy")
> 
> # atacontrol list
> ATA channel 0:
>     Master:      no device present
>     Slave:       no device present
> ATA channel 1:
>     Master:      no device present
>     Slave:       no device present
> ATA channel 2:
>     Master:  ad4 <WDC WD2500KS-00MJB0/02.01C03> Serial ATA II
>     Slave:   ad5 <WDC WD2500KS-00MJB0/02.01C03> Serial ATA II
> ATA channel 3:
>     Master:  ad6 <WDC WD2500KS-00MJB0/02.01C03> Serial ATA II
>     Slave:       no device present
> 
> # grep -i ata /var/run/dmesg.boot 
> atapci0: <Intel ICH7 UDMA100 controller> port
> 0x1f0-0x1f7,0x3f6,0x170-0x177,0x376,0x30b0-0x30bf irq 18 at device 31.1
> on pci0
> ata0: <ATA channel 0> on atapci0
> ata1: <ATA channel 1> on atapci0
> atapci1: <Intel ICH7 SATA300 controller> port
> 0x30c8-0x30cf,0x30e4-0x30e7,0x30c0-0x30c7,0x30e0-0x30e3,0x30a0-0x30af
> mem 0x88200000-0x882003ff irq 19 at device 31.2 on pci0
> ata2: <ATA channel 0> on atapci1
> ata3: <ATA channel 1> on atapci1
> ad4: 238475MB <WDC WD2500KS-00MJB0 02.01C03> at ata2-master SATA150
> ad5: 238475MB <WDC WD2500KS-00MJB0 02.01C03> at ata2-slave SATA150
> ad6: 238475MB <WDC WD2500KS-00MJB0 02.01C03> at ata3-master SATA150
> 
> Any guidance on this would be greatly appreciated.  Thanks,
> Dane
>