Check 64 bit DMA from Disk-Controller (amd64/135040)

[Torfinn Ingolfsen]

Hello,

On Tue, 01 Feb 2011 20:17:36 +0100
Ralf Folkerts <ralf.folkerts at gmx.de> wrote:

> My SB600 ATA-Controller used to cause massive Problems (from disk not 
> being detected at all to disk being detected but later "trashed" during 
> buildworld) with DMA with 4G RAM. I circumvented that by setting 
> "hw.physmem=4g", as recommended by John Baldwin.

Interesting. I have a machine[1] with the SB600, but so far it has
mostly been running FreeBSD 6.x and 7.x / amd64.
However, I recently installed Linux (Ubuntu) on a partition on that
same machine, and it shows some interesting things in dmesg output:

[    0.698790] ehci_hcd 0000:00:13.5: applying AMD SB600/SB700 USB freeze workaround
[    1.448022] ata3: applying SB600 PMP SRST workaround and retrying
[    1.449522] ata4: applying SB600 PMP SRST workaround and retrying
[    1.619986] ata4.00: SB600 AHCI: limiting to 255 sectors per cmd
[    1.626505] ata4.00: SB600 AHCI: limiting to 255 sectors per cmd
[    1.632688] ata3.00: SB600 AHCI: limiting to 255 sectors per cmd
[    1.634745] ata3.00: SB600 AHCI: limiting to 255 sectors per cmd

which may or may not be related.

According the the bios upgrade info for mny machine, some usb problem has been fixed
by the latest bios upgrade (the machine used to hang when booting
if any usb devices were plugged in).
I haven't seen any trouble with the disk controller (but the machine has
only had a single disk attached until recently).

References:
1) http://sites.google.com/site/tingox/asus_m2a-vm_hdmi
-- 
Torfinn