Re: Marvel PMP SATA controller

[Richard <tuxbox.guru@gmail.com>]

On 01/10/10 01:24, Robert Hancock wrote:
> On 09/30/2010 08:03 AM, Richard wrote:
>> On 30/09/10 14:39, Mark Lord wrote:
>>> On 10-09-29 04:32 PM, Richard wrote:
>>>> On 29/09/10 20:56, Mark Lord wrote:
>>>
>>>>> What are you trying to do?
>>>> Hi Mark,
>>>>
>>>> Its an embedded device whereby the one HDD I have does not work with
>>>> the Marvel PMP. I have the command to send to the PMP controller but
>>>> I am not an officianado with linux SATA(the code I have is from
>>>> VxWorks) The drive is confirmed working, but the PMP chip does not
>>>> default to SATA Generation 1, and this HDD is a bit dumb to figure it
>>>> out :) - so I have to force the PMP controller to Gen1 mode.
>>>> (I have tons of drives that work just fine, its just this ONE Maxtor
>>>> drive that is being a pain)
>>>>
>>>> The short - I need to write a command to the SATA controller before
>>>> this HDD can be recognised.
>>> ..
>>>
>>> Does the existing libata parameter take care of it for you?
>>>
>>> linux/Documentation/kernel-parameters.txt:
>>> eg. libata.force=[ID:]1.5" ## replace [ID:] with port[.device] for the
>>> PMP and/or HD
>>>
>> Unfortunately not.. which is why I asked how to write commands directly
>> on to the SATA bus from kernel space.
>
> Looking at the code it seems like it should.. what kernel version are 
> you using? See sata_set_spd in libata-core.c, which calls 
> sata_scr_write, which calls sata_pmp_scr_write if it's not a host link..
Its a bit more than 'Put it in to 1.5Gbps speed' - Even when selecting 
this speed nothing happens. When I write to the PMP controller using a 
Finisar SATA analyser (Write 0xE8 Register 0x02 Value 0x11) which 
according to the Marvel specifications is 'Set to SATA Generation 1 and 
Reset Drive' things start to happen.  Unfortunately the kernel is a 
2.6.18 one and there is no hope of updating it in the short term as its 
used across many projects.

Richard