Re: sata_nv times out for BD-ROM iHOS104-08

From: Cengiz GÃnay
Date: Sun Feb 28 2010 - 12:25:26 EST


Hi Tejun,

On Mon, Feb 22, 2010 at 9:38 PM, Tejun Heo <tj@xxxxxxxxxx> wrote:
> On 02/22/2010 06:28 AM, Cengiz GÃnay wrote:
>> I was able to read a regular DVD in the drive. According to dmesg the
>> negotiated speed was down to UDMA/33, so I am not sure about the
>> performance of the drive.
>
> Hmmm.... it could be that the drive is sending more data then
> requested and the state machine in the controller doesn't like that
> and fails to assert IRQ on the host side. You're still getting
> timeouts on 96 byte dma inquiries. Can you please this patch?

Before and after the swncq-atapi-pio patch I still get awful read
times from the BD-ROM drive:

$ time dd if=/dev/sr0 of=/dev/null bs=64k count=1024
67108864 bytes (67 MB) copied, 106.945 seconds, 628 kB/s
=> real 1m46.977s

Compared to reading the same DVD in my DVD-ROM drive:

$ time dd if=/dev/hda of=/dev/null bs=64k count=1024
67108864 bytes (67 MB) copied, 13.8403 seconds, 4.8 MB/s
=> real 0m13.860s

I attached the full dmesg after the swncq-atapi-pio patch.

-Cengiz

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