suspend/resume (Xilinx V4)

suspend/resume (Xilinx V4)

[John Williams]

Hi,

Any comments on the status/feasibility of suspend/resume for LinuxPPC on 
Xilinx devices?

The only suspend-related traffic I see here in the last 12 months is for 
the lite5200b board.

Any guesstimates of level of difficulty for such a task on Xilinx 
PPC405?  The core lite5200b patchset didn't look too hairy (just a 
modest bit of ASM :), but there would also be Xilinx device driver hooks 
to consider.

Also, are there kernel revision dependencies here?  Project is currently 
on an MVL 2.6.10 tree - but have seen mention of 2.6.17 (?) being 
earliest with PPC suspend/resume capability.

All info appreciated.  Thanks,

John

Re: suspend/resume (Xilinx V4)

[Grant Likely]

On 8/2/07, John Williams <jwilliams@itee.uq.edu.au> wrote:
> Hi,
>
> Any comments on the status/feasibility of suspend/resume for LinuxPPC on
> Xilinx devices?

Pretty much non-existant as far as status goes.  Feasibility depends
entirely on what power management features the Xilinx silicon
supports.  I haven't looked into whether or not the 405 core can be
put into sleep states.

>
> The only suspend-related traffic I see here in the last 12 months is for
> the lite5200b board.
>
> Any guesstimates of level of difficulty for such a task on Xilinx
> PPC405?  The core lite5200b patchset didn't look too hairy (just a
> modest bit of ASM :), but there would also be Xilinx device driver hooks
> to consider.

I suspect the driver code will be where most of the effort lies.

> Also, are there kernel revision dependencies here?  Project is currently
> on an MVL 2.6.10 tree - but have seen mention of 2.6.17 (?) being
> earliest with PPC suspend/resume capability.

Suspend support for ppc has existed for a long time, but there aren't
many embedded ppc boards which support it (5200 being a notable
example).

Personally, I'm keeping up to date with mainline (2.6.22+) on my Virtex tree.

Cheers,
g.

-- 
Grant Likely, B.Sc., P.Eng.
Secret Lab Technologies Ltd.
grant.likely@secretlab.ca
(403) 399-0195