IDE system bus speed

moger · 02-09-2004, 03:16 PM

My dmesg produces the following:
ide: Assuming 33MHz system bus speed for PIO modes; override with idebus=xx

My drive is an ATA 100 disk but it's assuming only 33mhz. Can I just put the line idebus=100 in my lilo.conf - or does it go somewhere else?

jtshaw · 02-09-2004, 03:24 PM

Do you have a line that looks like those below anywhere? If so, what does it say UDMA(100) or something else? I am afraid the 33Mhz. might refer to your pci bus clock which probably is 33 mhz.

Code:

hde: 90069840 sectors (46115 MB) w/1916KiB Cache, CHS=65535/16/63, UDMA(100)
 /dev/ide/host2/bus0/target0/lun0: p1 p2 p3
hdh: max request size: 128KiB
hdh: 78165360 sectors (40020 MB) w/2048KiB Cache, CHS=65535/16/63, UDMA(100)
 /dev/ide/host2/bus1/target1/lun0: p1

snacky · 02-09-2004, 03:49 PM

jtshaw is right. If you're feeling adventurous, you might try 40 or 50 MHz. I'm pretty sure it's not 100

Since you're probably using a UDMA mode for talking to the drive anyway, I doubt it makes any difference (though I'm far from being an expert on this subject).

When I wonder what the messages mean, I try grep -r for them in the kernel source. I noticed the same thing and have come to the conclusion it's nothing to worry about.

gnashley · 02-10-2004, 02:54 PM

I think PIO was for very old hard drives before the ATA standard came along, so it wouldn't have any effect on a newer system. i have an old 100MHz pentium-s with ancient hard drive that boots with PIO messages.

moger · 02-10-2004, 06:55 PM

Quote:

Originally posted by gnashley
I think PIO was for very old hard drives before the ATA standard came along, so it wouldn't have any effect on a newer system. i have an old 100MHz pentium-s with ancient hard drive that boots with PIO messages.

So it thinks my ATA100 drive is using PIO?

snacky · 02-10-2004, 07:29 PM

no, but if it WERE using PIO, that's the bus speed it would assume.

So the message is nothing to be concerned about.

Vittorio · 02-14-2004, 12:16 PM

Greetings. I have some "similar" problem. My dmesg after some cleaning up shows this:

Code:

ide: Assuming 33MHz system bus speed for PIO modes; override with idebus=xx
VP_IDE: IDE controller at PCI slot 00:07.1
VP_IDE: chipset revision 6
VP_IDE: not 100% native mode: will probe irqs later
VP_IDE: VIA vt82c686b (rev 40) IDE UDMA100 controller on pci00:07.1
    ide0: BM-DMA at 0x9000-0x9007, BIOS settings: hda:pio, hdb:DMA
    ide1: BM-DMA at 0x9008-0x900f, BIOS settings: hdc:pio, hdd:DMA
HPT370A: IDE controller at PCI slot 00:0e.0
PCI: Found IRQ 11 for device 00:0e.0
PCI: Sharing IRQ 11 with 00:09.0
HPT370A: chipset revision 4
HPT370A: not 100% native mode: will probe irqs later
HPT37X: using 33MHz PCI clock
    ide2: BM-DMA at 0xc400-0xc407, BIOS settings: hde:DMA, hdf:DMA
    ide3: BM-DMA at 0xc408-0xc40f, BIOS settings: hdg:pio, hdh:pio
hdb: CD-W540E, ATAPI CD/DVD-ROM drive
hdd: HL-DT-STDVD-ROM GDR8161B, ATAPI CD/DVD-ROM drive
hde: WDC WD800BB-00BSA0, ATA DISK drive
hdf: WDC WD200EB-00BHF0, ATA DISK drive
ide0 at 0x1f0-0x1f7,0x3f6 on irq 14
ide1 at 0x170-0x177,0x376 on irq 15
ide2 at 0xb400-0xb407,0xb802 on irq 11
hde: attached ide-disk driver.
hde: host protected area => 1
hde: 156301488 sectors (80026 MB) w/2048KiB Cache, CHS=155061/16/63
hdf: attached ide-disk driver.
spurious 8259A interrupt: IRQ7.
hdf: host protected area => 1
hdf: 39102336 sectors (20020 MB) w/2048KiB Cache, CHS=38792/16/63
ide-cd: passing drive hdb to ide-scsi emulation.
ide-cd: passing drive hdd to ide-scsi emulation.
hdb: attached ide-scsi driver.
hdd: attached ide-scsi driver.

Now, I'm worried about not 100% native mode that my controllers work in, and the fact that I do not have UDMA(100) shown after the disk information, like jtshaw posted. ide2 shows hde and hdf have DMA enabled, but is it really effective or not?

Should I add hde=scsi and hdf=scsi to the append instruction in lilo.conf? What would it change?

Oh, yes, I use Debian Sarge, actually Knoppix installed to hard disk.

Thanks,

Viktor