Re: IDE DMA/VIA woes on SuSE 2.4.19-167

[Matthias Andree]

On Wed, 05 Mar 2003, Matthias Andree wrote:

> Plextor PX-W4824TA 1.03 as hdc (no hdd)
> VIA KT133
> 
> 00:07.1 IDE interface: VIA Technologies, Inc. VT82C586B PIPC Bus Master IDE (rev 10) (prog-if 8a [Master SecP PriP])
>         Flags: bus master, medium devsel, latency 32
>         I/O ports at ffa0 [size=16]
>         Capabilities: [c0] Power Management version 2
> 
> When I try to enable DMA (hdparm -d1 or hdparm -d1 -X66), hdparm -tT
> chokes, SuSE k_athlon-2.4.19-167. FreeBSD-5 (with atapicam) is fine and
> uses UDMA33.

Now, seems that PIO manages the default hdparm -tT block size, but DMA
doesn't; but the error messages in the kernel ring buffer aren't
specific.

I let go of hdparm -tT, installed Jörg Schilling's sdd and ran sdd
if=/dev/sr1 -onull -t bs=2048 and lo and behold, it passed and read a
data CD with up to 45x. So the remaining problem is that the ATAPI
drives stick to PIO for data reads.

I tried applying Andrew's ide-akpm on top of SuSE's kernel, to find it
crashes on boot on SuSE's hardware scan.

If that's interesting enough, I can try to dig up the crash messages
(I'll have to use a serial console for that though).