Comparatively minor problem with via ide.

From: Philip Langdale (
Date: Fri Feb 09 2001 - 16:21:10 EST


I've just upgraded to an Athlon+KT133 from a P3+pro133 setup.

For the old motherboard which had a 596b southbridge I got
perfect udma66 support form my hard drives. After I switched
over, and without changing anything except switching from
p3 to athlon optimisations, the driver reports my drives running
at udma33. This is despite detecting an 80w cable, using ide0=ata66
and turning word93 checking off. The new southbridge is a 686b.

Also, possibly semi-related; it insists on detecting my ls-120 drive
as udma22 even though mwdma11 is the best it can actually do.

I'm not experiencing any corruption, fingers crossed ( I understand
that that was traced to an acpi conflict? ) but this is nevertheless
incorrect behaviour.


----------VIA BusMastering IDE Configuration----------------
Driver Version: 3.20
South Bridge: VIA vt82c686b
Revision: ISA 0x40 IDE 0x6
BM-DMA base: 0xd000
PCI clock: 33MHz
Master Read Cycle IRDY: 0ws
Master Write Cycle IRDY: 0ws
BM IDE Status Register Read Retry: yes
Max DRDY Pulse Width: No limit
-----------------------Primary IDE-------Secondary IDE------
Read DMA FIFO flush: yes yes
End Sector FIFO flush: no no
Prefetch Buffer: no no
Post Write Buffer: no no
Enabled: yes yes
Simplex only: no no
Cable Type: 80w 80w
Address Setup: 30ns 30ns 30ns 60ns
Cmd Active: 90ns 90ns 90ns 90ns
Cmd Recovery: 30ns 30ns 90ns 90ns
Data Active: 90ns 90ns 90ns 90ns
Data Recovery: 30ns 30ns 30ns 90ns
Cycle Time: 60ns 60ns 60ns 90ns
Transfer Rate: 33.3MB/s 33.3MB/s 33.3MB/s 22.2MB/s

and relevant dmesg:

Uniform Multi-Platform E-IDE driver Revision: 6.31
ide: Assuming 33MHz system bus speed for PIO modes; override with idebus=xx
VP_IDE: IDE controller on PCI bus 00 dev 39
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
VP_IDE: ATA-66/100 forced bit set (WARNING)!!
    ide0: BM-DMA at 0xd000-0xd007, BIOS settings: hda:DMA, hdb:DMA
    ide1: BM-DMA at 0xd008-0xd00f, BIOS settings: hdc:DMA, hdd:DMA
hda: IBM-DPTA-372730, ATA DISK drive
hdd: LS-120 VER5 00 UHD Floppy, ATAPI FLOPPY drive
ide0 at 0x1f0-0x1f7,0x3f6 on irq 14
ide1 at 0x170-0x177,0x376 on irq 15
hda: 53464320 sectors (27374 MB) w/1961KiB Cache, CHS=3328/255/63, UDMA(33)
hdb: 12594960 sectors (6449 MB) w/418KiB Cache, CHS=784/255/63, UDMA(33)
hdc: ATAPI 32X DVD-ROM drive, 256kB Cache, UDMA(33)
Uniform CD-ROM driver Revision: 3.12
hdd: 123264kB, 963/8/32 CHS, 533 kBps, 512 sector size, 720 rpm
ide-floppy: hdd: I/O error, pc = 5a, key = 5, asc = 24, ascq = 0

hdparm reports that the drives are udma66 capable which is correct, but how
do I convince the driver to use it?



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This archive was generated by hypermail 2b29 : Thu Feb 15 2001 - 21:00:14 EST