Re: Bad CD disk disables IDE DMA

From: Zoltan Boszormenyi
Date: Thu Aug 16 2007 - 06:59:27 EST


Michal Piotrowski írta:
Hi Zoltan,

On 15/08/07, Zoltan Boszormenyi <zboszor@xxxxxxxxxx> wrote:
Hi,

I noticed that a bad CD of mine makes DMA disabled:

hda: selected mode 0x44
hda: cdrom_decode_status: status=0x51 { DriveReady SeekComplete Error }
hda: cdrom_decode_status: error=0x40 { LastFailedSense=0x04 }
ide: failed opcode was: unknown
hda: cdrom_decode_status: status=0x51 { DriveReady SeekComplete Error }
hda: cdrom_decode_status: error=0x40 { LastFailedSense=0x04 }
ide: failed opcode was: unknown
hda: cdrom_decode_status: status=0x51 { DriveReady SeekComplete Error }
hda: cdrom_decode_status: error=0x40 { LastFailedSense=0x04 }
ide: failed opcode was: unknown
hda: cdrom_decode_status: status=0x51 { DriveReady SeekComplete Error }
hda: cdrom_decode_status: error=0x40 { LastFailedSense=0x04 }
ide: failed opcode was: unknown
hda: DMA disabled
hda: ide_intr: huh? expected NULL handler on exit
hda: ATAPI reset complete

Every time I put the said CD into to drive and DMA is on, I get the
above messages.

This might be intended.

Might be. Note however, that there are no "cdrom_decode_status: " lines
when the drive is not using DMA. The disk is the same in both cases.
I don't know too much about ATAPI, but shouldn't it report the same
errors no matter how the commands are passed to the drive?
I tried to make it using DMA after mounting the "faulty" disk and copying it.
The same errors occured in the logs when dd started reading but it actually
finished reading:

$ LANG=C dd if=/dev/hda of=image.iso bs=2048
dd: reading `/dev/hda': Input/output error
298106+0 records in
298106+0 records out
610521088 bytes (611 MB) copied, 144.349 seconds, 4.2 MB/s

The file is a bit larger than what isosize reports about it but IIRC it's expected.
So, if the disk is actually faulty dd would drop dead and not able to read the disk.
Or something is not quite right in the ide-cd driver. The "DMA disabled" message
comes when the drive should spin up the disk. Isn't there a timeout error somewhere?
Hm. Thinking about it a bit more upon mount the same is happening - before
the disk is spun up the error shows up in the logs and it switches to PIO.
Does it ring a bell to someone?

Two things are interesting: first, it gets mounted correctly and
readable and
second, when DMA was already disabled no such messages occur in the logs.
Anyhow, I would need DMA to correctly burn CDs/DVDs...
What can I do besides manually re-enable DMA?
All other disks I have tried behave perfectly.
This happened on 2.6.22[-rcX], 2.6.23-rc3-git1 and 2.6.20-1.2962.fc6.
This is on a Fedora Core 6 system. CD/DVD is using the old IDE drivers:

Uniform Multi-Platform E-IDE driver Revision: 7.00alpha2
ide: Assuming 33MHz system bus speed for PIO modes; override with idebus=xx
NFORCE-MCP55: IDE controller at PCI slot 0000:00:04.0
NFORCE-MCP55: chipset revision 161
NFORCE-MCP55: not 100% native mode: will probe irqs later
NFORCE-MCP55: BIOS didn't set cable bits correctly. Enabling workaround.
NFORCE-MCP55: 0000:00:04.0 (rev a1) UDMA133 controller
ide0: BM-DMA at 0xf000-0xf007, BIOS settings: hda:DMA, hdb:DMA
Probing IDE interface ide0...
hda: PIONEER DVD-RW DVR-111L, ATAPI CD/DVD-ROM drive
ide0 at 0x1f0-0x1f7,0x3f6 on irq 14
Probing IDE interface ide1...
ide-floppy driver 0.99.newide

$ cat /proc/ide/amd74xx
----------AMD BusMastering IDE Configuration----------------
Driver Version: 2.13
South Bridge: 0000:00:04.0
Revision: IDE 0xa1
Highest DMA rate: UDMA133
BM-DMA base: 0xf000
PCI clock: 33.3MHz
-----------------------Primary IDE-------Secondary IDE------
Prefetch Buffer: yes yes
Post Write Buffer: yes yes
Enabled: yes no
Simplex only: no yes
Cable Type: 80w 80w
-------------------drive0----drive1----drive2----drive3-----
Transfer Mode: PIO DMA DMA DMA
Address Setup: 30ns 90ns 90ns 90ns
Cmd Active: 90ns 90ns 300ns 300ns
Cmd Recovery: 30ns 30ns 300ns 300ns
Data Active: 90ns 330ns 330ns 330ns
Data Recovery: 30ns 270ns 270ns 270ns
Cycle Time: 120ns 600ns 600ns 600ns
Transfer Rate: 16.6MB/s 3.3MB/s 3.3MB/s 3.3MB/s

Best regards,
Zoltán Böszörményi

Regards,
Michal


Best regards,
Zoltán


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