In article <fa.in6m4av.u5iq9d@ifi.uio.no>, Andrzej Krzysztofowicz <ankry@green.mif.pg.gda.pl> writes:
Hi,
>> >From dmesg I have,
>>
>> ALI15X3: MultiWord DMA enabled
>> hda: Maxtor 90680D4, 2014MB w/256kB Cache, CHS=826/255/63, (U)DMA
> ^^^^
> This means that kernel decides your chipset is not UDMA capable, while the
> drive is...
>
> Note, that driver author (from ALI) suggested that for M5229 rev. <= 0x20
> UDMA is "not stable", so it should be disabled by the driver...
Thanks for pointing this out. Do you know what the upgrade possibilities
to a later rev. are? I could not find any useful info on Ali's website. Is
the rev. 0x20 code h/w or firmware in the chip? If f/w can it be upgraded?
Does anybody know the nature of the 'instability' ?
> I observe, that for many BIOSes timings are calculated basing on maximum
> possible PCI clock (42.5 MHz ?) rather than on currently being set one.
> It effects in a bit worse transfer results. To test it you can try:
>
> 1. put the idebus=... parameter to the kernel during boot
> (I use idebus=30, as set on my MoBo)
> 2. hdparm -d0 ...
> 3. hdpatm -p ... # calculate new timings
> 4. hdparm -X34 ...
> 5. hdparm -d1 ...
>
> Difference shouldn't be meaningfull, but results slightly better.
I hope to try this once I have backed-up my root HD. I'm puzzled by the
argument to idebus. Where do you get the 30 from? I cannot find any
mention of ide bus speeds in my MB manual. It just says it supports 'bus
master ide dma 33MHz/sec'...
On a related issue: I find kernel 2.3.37 which I am running at the moment
does not report the "ide: Assuming xxMHz system bus speed..." at all.
Previously I was running 2.3.24 which did report 40MHz assumed speed. I
did a quick grep of the two sources and the routines for this in
drivers/block/{ide.c,ali15x3.c} are the same. Any idea whats going on?
Regards
Tom.
-- Tom Crane, Dept. Physics, Royal Holloway, University of London, Egham Hill, Egham, Surrey, TW20 0EX, England. Email: uhap023@vms.rhbnc.ac.uk SPAN: 19.875 Fax: 01784 472794- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/
This archive was generated by hypermail 2b29 : Sun Jan 23 2000 - 21:00:13 EST