Re: [Ocf-linux-users] OCF compatible driver for HiFN Xcellerator Card 8155HXL-G

[David M. <Dav...@se...>]

Jivin hiren joshi lays it down ...
> Hello,
> 
> Thank you for the answer.
> 
> > I think you need to get the appropriate "devkit" from hifn, then write a
> > driver somewhat along the lines of either ixp4xx driver or the ep80579
> > driver that also rely on externally provided devkits.
> 
> Yes, I am having the SDK.
> 
> > It is usually a much simpler task to support such devices at they have a
> > nice API etc and you do not need to write a full HW driver.
> 
> I can think of two ways, and request you to comment on them.
> 
> 1. With OCF: Incorporate OCF glue in the existing driver I got with SDK.
> It will allow other sub-systems and applications to use the card.
> (As I have only one card, session migration is not relevant here.)

Whatever you feel works the best.  Starting with an existing OCF driver
and swapping the API calls to the hifn API would seem easiest to me,
but that is your call.

> 2. Without OCF: Native integration with Openswan (KLIPS) using the SDK APIs.
> This will help me to get full advantage of the card (protocol
> processing offloading).

The overhead that OCF adds to the crypto process is very small.  I did
this test with the IXP driver (look at ocf-bench.c to see the IXP native
and OCF parts of the test).

There was almost no reduction in crypto speed (IIRC < 1%).  This
basically means that #1 above is the best choice,  and it saves you have
to do anything in the openswan code and also lets you accelerate openssl
and potentially other things.

Cheers,
Davidm

-- 
David McCullough,  dav...@se...,  Ph:+61 734352815
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