>Number:         31110
>Category:       kern
>Synopsis:       siside(4) uses too low dma-mode on SiS650 IDE with FUJITSU MHR2020AT attached. patch exist{s|ed}.
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Wed Aug 31 15:44:00 +0000 2005
>Originator:     Dennis den Brok
>Release:        Applies to kernels at least up to 2.1_RC2.
>Organization:
-
>Environment:
NetBSD 2.1_RC2
>Description:
Kernel messages include: 

<missing stuff>, DMA mode 2, Ultra-DMA mode 5 (Ultra/100)
wd0(siside0:0:0): using PIO mode 4, Ultra-DMA mode 2 (Ultra/33) (using DMA data transfers)

This indeed has impact on the drive's speed.
>How-To-Repeat:
Boot a NetBSD kernel up to at least version 2.1_RC2 on a system as described.
>Fix:
I asked for a solution to this problem about three years ago (time's going by so fast) and was quickly supplied with a working patch from Manuel Bouyer which apparently never made it into CVS repository. Unfortunately, I don't have it anymore (and most probably it wouldn't be recent enough, anyway), maybe Manuel still has it or is able to reproduce it without much effort and can commit it to CVS?