Subject: Re: new SATA controller/drive _very_ slow (PIO mode 0)
To: Jim Bernard <jbernard@mines.edu>
From: Manuel Bouyer <bouyer@antioche.eu.org>
List: current-users
Date: 12/19/2007 20:55:53
On Wed, Dec 19, 2007 at 05:42:36AM -0700, Jim Bernard wrote:
> On Tue, Dec 18, 2007 at 11:40:08PM -0500, George Georgalis wrote:
> > 
> > pdcsata0 at pci4 dev 13 function 0
> > pdcsata0: Promise PDC40718 SATA300 controller (rev. 0x02)
> > pdcsata0: interrupting at ioapic0 pin 17 (irq 11)
> > pdcsata0: bus-master DMA support present
> 
>   The VIA card looks equally promising at that point:
> 
> viaide1 at pci0 dev 11 function 0
> viaide1: VIA Technologies VT6421 Serial RAID Controller (rev. 0x50)
> viaide1: bus-master DMA support present
> viaide1: using irq 10 for native-PCI interrupt
> ...
> viaide1 port 0: device present, speed: 1.5Gb/s
> 
> It's when the disk is configured that the mode is downgraded:
> 
> wd2 at atabus2 drive 0: <WDC WD5000AAKS-00YGA0>
> wd2: drive supports 16-sector PIO transfers, LBA48 addressing
> wd2: 465 GB, 969021 cyl, 16 head, 63 sec, 512 bytes/sect x 976773168 sectors
> wd2(viaide1:0:0): using PIO mode 0
> 
>   Does it actually use DMA for the disk(s)?

No.
It's strange that the drive doesn't report any supported PIO or DMA mode.

-- 
Manuel Bouyer <bouyer@antioche.eu.org>
     NetBSD: 26 ans d'experience feront toujours la difference
--