Re: HDD power up in standby

[Robert Hancock]

2009/12/14 Janos Haar <janos.haar@xxxxxxxxxxxx>:
> Hello,
>
> ----- Original Message ----- From: "Robert Hancock" <hancockrwd@xxxxxxxxx>
> To: "Janos Haar" <djani22@xxxxxxxxxxxx>
> Cc: <linux-kernel@xxxxxxxxxxxxxxx>
> Sent: Tuesday, December 15, 2009 2:02 AM
> Subject: Re: HDD power up in standby
>
>
>> On 12/14/2009 04:22 AM, Janos Haar wrote:
>>>
>>> Hello list,
>>>
>>> I have posted to the common, because this theme is for more lists (ide,
>>> sata, scsi), i think....
>>>
>>> I know you will not like me guys, but i have one wish.... :-)
>>>
>>> I am building cheap but big storages, and after 12 drive / PC i have
>>> faced
>>> with one problem:
>>> The too much spinup current wich made by the 12-16 drive at the same
>>> time.
>>> In my actual case, in 12V, there is more than 2A / drive for some
>>> seconds.
>>>
>>> I know, in SCSI, there is a jumper for this, and the card can wake up the
>>> drives one by one, but i am using 2TB drives, and in SCSI/SAS this have
>>> horrible price...
>>> I have done some invesrtigation, and found this:
>>> The most of the simple sata drives handles the PUIS mode (by set
>>> features ata command), but unfortunately
>>> only the professional and expensive raid cards supports the wakeing up.
>>> If the cheap cards founds only 0 byte drives, this is not a problem at
>>> all,
>>> because linux usually not use BIOS support fortunately. :-)
>>> But i have found when i have spent a little time in google, and in the
>>> documentation, linux doesn't support PUIS.
>>>
>>> I think this would be great, and (relatively) simple to implement this
>>> feature.
>>> I can imagine in this way:
>>> Wake up from PUIS is disabled by default, but can be enabled by command
>>> line
>>> parameter, or compile time configuration.
>>> The drivers should send the wake up command one by one to the drives,
>>> waits
>>> for RDY DSC, and than scan the drives, and register....
>>>
>>> What do you think?
>>
>> As far as I can see, if the drive reports it's in power-up in standby mode
>> from the identify response, the kernel will send the command to spin up the
>> drive. It might depend on whether parallel scan is enabled for the
>> controller as far as whether they actually spin up one at a time, however.
>
> I am working with 2TB Hitachi drive wich is set to PUIS, and reports itself
> as 0 byte, but existing device (pcb factory alias), but with my promise
> card, the kernel see only bad geometry and disable the port only. :-(
> I have missed something?

Can you post the full boot log?
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/