2007-02-18 05:26:47

by Brandon Low

[permalink] [raw]
Subject: 2.6.20: libata PATA ATAPI CDROM weirdness on ALI

I'm having some weirdness during boot with my optical drives on 2.6.20.

ata2.00: ATAPI, max UDMA/33
ata2.01: ATAPI, max UDMA/33
ata2.00: qc timeout (cmd 0xef)
ata2.00: failed to set xfermode (err_mask=0x4)
ata2.00: limiting speed to UDMA/25
ata2: failed to recover some devices, retrying in 5 secs
ata2.00: configured for UDMA/25
ata2.01: configured for UDMA/33

the 4 lines starting with qc timeout _would_ repeat with lower speeds
until the drive was finally disabled and then do the same for 2.01,
except that on this particular attempt, I had the thought to eject both
optical drives while it sat there. Boot then proceeded normally and the
drives appear to work.

Intuitively this seems to indicate that the drives aren't being sent
some kind of wake-up call before their transfer modes are set.

The motherboard is an ASRock 939 Dual SATA II.

Let me know if there is any more information that I can provide.

Thanks,

Brandon Low


2007-02-18 05:58:23

by Andrey Borzenkov

[permalink] [raw]
Subject: Re: 2.6.20: libata PATA ATAPI CDROM weirdness on ALI

Brandon Low wrote:

> I'm having some weirdness during boot with my optical drives on 2.6.20.
>
> ata2.00: ATAPI, max UDMA/33
> ata2.01: ATAPI, max UDMA/33
> ata2.00: qc timeout (cmd 0xef)
> ata2.00: failed to set xfermode (err_mask=0x4)
> ata2.00: limiting speed to UDMA/25
> ata2: failed to recover some devices, retrying in 5 secs
> ata2.00: configured for UDMA/25
> ata2.01: configured for UDMA/33
>
> the 4 lines starting with qc timeout _would_ repeat with lower speeds
> until the drive was finally disabled and then do the same for 2.01,
> except that on this particular attempt, I had the thought to eject both
> optical drives while it sat there. Boot then proceeded normally and the
> drives appear to work.
>
> Intuitively this seems to indicate that the drives aren't being sent
> some kind of wake-up call before their transfer modes are set.
>
> The motherboard is an ASRock 939 Dual SATA II.
>

In my case of relatively old ALi chipset CD-ROM was never detected if DMA is
allowed. Unfortunately this remained mystery for quite some time. Legacy
IDE drivers are working just fine; it is only pata_ali that failes :(

See e.g. http://marc.theaimsgroup.com/?l=linux-kernel&m=116500554505311&w=2
(2.6.19: ALi M5229 - CD-ROM not found with pata_ali)

if you have any idea how to debug it ...

-andrey


> Let me know if there is any more information that I can provide.
>
> Thanks,
>
> Brandon Low