Thank you a lot!

> > entries in syslog from kernel 2.4.22 upgraded from Debian woody (gcc
> > 2.95.4) running on AMD K6II 450MHz with 64MB RAM. I don't have such
> > problem in kernel 2.4.20 upgraded from Slackware (gcc 2.95.3) running on
> > another box with the identical CPU and main board (but with 192MB RAM).
> > Does this message hurt anything?
> 
> Can you please provide additional details about your hardware?
> What kind of main board are you using, and what southbridge?

Now I found that the two boards are slightly different. The printings on
the biggest 2 chips on the problematic board are:

ALi
M1542 A1
100MHz
9949 TS05

ALi
M1543C B1
9947 TM07

respectively. While the board having no i8253 messages has the chips:

ALi
M1542 A1
100MHz
9937 TS05

ALi
M1543C B1
0002 TM05

> What is the reported latency of your IDE interface?

Sorry! I don't quite understand the meanings! I am trying to report all I
know about. dmesg on the problematic box shows:

Uniform Multi-Platform E-IDE driver Revision: 7.00beta4-2.4
ide: Assuming 33MHz system bus speed for PIO modes; override with
idebus=xx
hda: FUJITSU MPE3064AT, ATA DISK drive
ide0 at 0x1f0-0x1f7,0x3f6 on irq 14
hda: attached ide-disk driver.
hda: 12672450 sectors (6488 MB) w/512KiB Cache, CHS=13410/15/63
Partition check:
 hda: [PTBL] [788/255/63] hda1

One thing I want to mention here is that this disk supports 66MHz DMA
access according to Fjuitsu's whitepaper. OTOH, the board running kernel
2.4.20 reports:

Uniform Multi-Platform E-IDE driver Revision: 6.31
ide: Assuming 33MHz system bus speed for PIO modes; override with
idebus=xx
ALI15X3: IDE controller on PCI bus 00 dev 78
PCI: Assigned IRQ 10 for device 00:0f.0
ALI15X3: chipset revision 194
ALI15X3: not 100% native mode: will probe irqs later
    ide0: BM-DMA at 0xf000-0xf007, BIOS settings: hda:DMA, hdb:DMA
    ide1: BM-DMA at 0xf008-0xf00f, BIOS settings: hdc:DMA, hdd:DMA
hda: Maxtor 91021U2, ATA DISK drive
ide: Assuming 33MHz system bus speed for PIO modes; override with
idebus=xx
hdc: Maxtor 91021U2, ATA DISK drive
ide0 at 0x1f0-0x1f7,0x3f6 on irq 14
ide1 at 0x170-0x177,0x376 on irq 15
blk: queue c02c60a4, I/O limit 4095Mb (mask 0xffffffff)
hda: 20010816 sectors (10246 MB) w/512KiB Cache, CHS=1245/255/63,
UDMA(66)
blk: queue c02c6408, I/O limit 4095Mb (mask 0xffffffff)
hdc: 20010816 sectors (10246 MB) w/512KiB Cache, CHS=19852/16/63,
UDMA(66)
Partition check:
 hda: hda1
 hdc: [PTBL] [1245/255/63] hdc1

which looks to me that it supports DMA 66 as expected. I set the bios' of
these 2 boxes to the same parameters related to IDE in menu "Integrated
Peripherals".

Best Regards,

CN

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