Re: [Ocf-linux-users] talitos driver should be preemtive

[David M. <dav...@mc...>]

Jivin  ALEXANDRU IONUT GRAMA lays it down ...
> Con fecha 27/5/2010, "Kim Phillips" <kim...@fr...>
> escribi??:
> 
> >On Thu, 27 May 2010 02:10:12 +0200
> >" ALEXANDRU IONUT GRAMA" <ai....@al...> wrote:
> >
> >> Con fecha 26/5/2010, "Kim Phillips" <kim...@fr...>
> >> escribi??:
> >
> >> >It should be straightforward to convert talitos to support SEC 1.x h/w;
> >> >it has a different ring buffer mechanism (which, if I knew more about,
> >> >I'd be able to tell you whether it allowed simultaneous ciphers and
> >> >hashes)...
> >> 
> >> Thank you Kim, I dind't know I shouldn't load the cryptosoft module. In
> >> this guide(
> >> http://www.docunext.com/wiki/My_Notes_on_Patching_2.6.22_with_OCF#The_Results
> >> ),the author uses cryptosoft, and I thought that I should load it. I've
> >> found a guide of SEC1.x at this website:
> >> http://cache.freescale.com/files/32bit/doc/user_guide/SEC1SWUG.pdf?fpsp=1&WT_TYPE=Users%20Guides&WT_VENDOR=FREESCALE&WT_FILE_FORMAT=pdf&WT_ASSET=Documentation
> >
> >that's a guide for a different, standalone driver.
> >
> Ok, I thought that the other driver makes the correct tasks for the
> kernel 2.4, and the values gived as triggers for the different
> operations are the same.
> >> This one give me the the values that I should send to the
> >> crypto-processor for doing the proper operation, but I don't know the
> >> meaning of the symbols included in the talitos source code. I want to
> >> adapt talitos for being fully compatible with SEC 1.x arch, and if my
> >> changes of the code are apropiate for the project, contribute with them
> >> to the OCF-project to provide integration with SEC1.x branch. So, David
> >> and Kim, when you have some time, could you please give me some
> >> explanation about the meaning of the simbols and functions that you use
> >> on talitos? It will be very apreciated!!!
> >
> >even though it was written based on a SEC v2 manual, most of the
> >references in the talitos driver should coincide with nomenclature used
> >in the MPC8272 PowerQUICC II Family Reference Manual, Rev. 2, Chapter
> >38: Security Engine (SEC).
> >
> >Keep in mind that since mainline linux added support for asynchronous
> >crypto, a new talitos driver has since been merged:
> >
> >http://git.kernel.org/?p=linux/kernel/git/herbert/cryptodev-2.6.git;a=blob;f=drivers/crypto/talitos.c;h=637c105f53d262f904230c77b5bc5a5a5234fda7;hb=master
> >
> >OCF can also utilize this driver through its cryptosoft interface
> >module, so depending on your license preference (OCF is Dual BSD/GPL,
> >kernel.org is GPL), it might be worth checking out.
> >
> 
> I've already checked the new module, but I thought that it's no way to
> make it compatible with cryptodev because it doesn't include any
> interface with cryptodev (I've look a bit into it, I didn't check it
> deeply). What I cannot understand how cryptosoft will know about the
> "new" talitos if talitos has only a interface to cryptoAPI. ???There's
> any patch that you have to apply for making cryptodev compatible with
> cryptoAPI?
> 
> Today I've spoke with my tutor about the actual situation of the
> project, and he told me that we need to submit some benchmarks about the
> IPsec's working now on June.
> 
> The point is that I'm not working with the base kernel 2.6.21, it's a
> patched version that includes a backport for UBI and other features that
> our system needs. So, I'm planning to switch to a kernel 2.6.34, so it
> means a lot of work to adapt the current patch for 2.5.34 version, that
> task being not trivial.
> 
> In summary, I'll return to cryptodev/kernel work on July, now I have
> exams and some IPsec benchmarks to do.When I'll finish those tasks,
> I'll have benchmarks without cryptodev, with cryptodev+cryptodev's
> talitos and with cryptodev+cryptosoft+talitos. I'll tell you the
> address where you can found those benchmarks and make an idea of the
> performance of cryptodev.


You can use the "in-kernel" version of the talitos driver with cryptodev by
using cryptosoft.  cryptosoft isn't just software,  it uses the kernels crypto
API,  so anything that is available there then becomes availabel to OCF.

The latest OCF release has a verison of cryptosoft that can use the kernels
newer ASYNC operations under cryptoAPI and thus also use the talitos HW
driver provided by the kernel.

The other alternative is to use the OCF talitos driver instead of cryptosoft.

Which one you choose depends on your requirements,  both time and performance.


Cheers,
Davidm


> >> >> Con fecha 25/5/2010, "David McCullough" <dav...@mc...>
> >> >> escribi??:
> >> >> 
> >> >> >
> >> >> >Jivin Kim Phillips lays it down ...
> >> >> >> On Wed, 26 May 2010 07:55:51 +1000
> >> >> >> David McCullough <dav...@Mc...> wrote:
> >> >> >>
> >> >> >> >
> >> >> >> > Jivin Kim Phillips lays it down ...
> >
> >> >> >> not a kernel pre-emption issue per se; I just wanted to mention it
> >> >> >> makes it harder to overcome serializing the overhead of sending the
> >> >> >> request to h/w and back.  Also, newer talitos h/w can perform ciphers
> >> >> >> and hashes simultaneously (I'm not sure if the 8272 can do that though).
> >> >> >
> >> >> >But the 8272 still has a queue for crypto requests right ?  Which means you
> >> >> >can have several outstanding requests to the HW at any point ?
> >
> >turns out the sec1.0 in the 8272 has four dma channels, so yes, it can
> >do a cipher and a hash at the same time.
> >
> >Cheers,
> >
> >Kim
> 
> 

-- 
David McCullough,      dav...@mc...,  Ph:+61 734352815
McAfee - SnapGear      http://www.mcafee.com         http://www.uCdot.org