ALI1489 IDE driver

Marek Michalkiewicz (marekm@i17linuxb.ists.pwr.wroc.pl)
Tue, 6 Aug 1996 00:31:27 +0200 (MET DST)


Hi,

I noticed that the recent kernels have support for the ALI 1487/9
chipset in the IDE driver. Now I'm just wondering - I have a GigaByte
GA-5486AL motherboard with this chipset and AMD 5x86-160 CPU, and
it works just fine with both the standard IDE driver, and 2.0.10
with ALI support enabled. I don't see any real speed difference
(except that the ALI support made it about two times _slower_ in
the older kernels). Are there any reasons why I should be using
the kernel with ALI 14xx support enabled? (The DOS driver doesn't
make a big difference under DOS either, so I don't use it.)

My disk is WDC AC2850F, using PIO mode 3, hdparm -m16, no unmasking
(no high speed serial I/O). hdparm -t /dev/hda reports about 3.9
MB/s "raw driver speed", which isn't bad for a drive which is about
a year old.

Also, 2.0.11 has the bus speed parameter. Allowed values are from
25 to 66 - but I suspect that with the CPU running externally at
40MHz, the PCI bus is running at only 20MHz (40 would be too fast
for the PCI specs). Perhaps the minimum value should be 20?
(Haven't tried 2.0.11 yet.)

Marek