[Qemu-devel] MIPS DSP for Qemu

[Qemu-devel] MIPS DSP for Qemu

[reed kotler]

I work for Mips in the compiler team.

A year and half ago, I did a complete implementation  for Mips DSP in Qemu.
My port has passed all the MIPS AVPs (Architectural Verification 
Programs) for DSP, which is something not available to the public but is 
what all architectural licenses and internal groups are required to pass.

In addition, my port implements DSP micro-mips.

When I finished my port I handed it over to our simulation team to push 
upstream and they never got around to doing it. We have several new Mips 
computers that have been developed in that time and they were busy with 
those projects.

It was about to get finally pushed upstream and then this new port appeared.

I would like to still submit our patches .

Please advise.

Out port is complete and already tested to a level which would be 
difficult for someone else to do that does not have access to our AVP 
test suite.

Reed

Re: [Qemu-devel] MIPS DSP for Qemu

[陳韋任 (Wei-Ren Chen)]

> I would like to still submit our patches .
> 
> Please advise.
> 
> Out port is complete and already tested to a level which would be 
> difficult for someone else to do that does not have access to our AVP 
> test suite.

  What about Jia's patch?

Regards,
chenwj

-- 
Wei-Ren Chen (陳韋任)
Computer Systems Lab, Institute of Information Science,
Academia Sinica, Taiwan (R.O.C.)
Tel:886-2-2788-3799 #1667
Homepage: http://people.cs.nctu.edu.tw/~chenwj

Re: [Qemu-devel] MIPS DSP for Qemu

[Peter Maydell]

On 3 October 2012 22:37, reed kotler <rkotler@mips.com> wrote:
> A year and half ago, I did a complete implementation  for Mips DSP in Qemu.
> My port has passed all the MIPS AVPs (Architectural Verification Programs)
> for DSP, which is something not available to the public but is what all
> architectural licenses and internal groups are required to pass.

> It was about to get finally pushed upstream and then this new port appeared.

...you could have mentioned this back in March when Jia first sent
his DSP related patches...

> I would like to still submit our patches .
>
> Please advise.

Well, if your patches are in what you believe to be a clean and
ready-for-upstream state anyway, you might as well submit them to
the mailing list so we can look at them. (you might want to read
http://wiki.qemu.org/Contribute/SubmitAPatch if you haven't already.)

I also note that target-mips/ is currently in the "Odd Fixes"
maintenance state -- is anybody at MIPS in a position to step
up and help with bug fixing and patch review of that area?

-- PMM

Re: [Qemu-devel] MIPS DSP for Qemu

[Aurelien Jarno]

On Wed, Oct 03, 2012 at 02:37:16PM -0700, reed kotler wrote:
> I work for Mips in the compiler team.
> 
> A year and half ago, I did a complete implementation  for Mips DSP in Qemu.
> My port has passed all the MIPS AVPs (Architectural Verification
> Programs) for DSP, which is something not available to the public
> but is what all architectural licenses and internal groups are
> required to pass.
> 
> In addition, my port implements DSP micro-mips.
> 
> When I finished my port I handed it over to our simulation team to
> push upstream and they never got around to doing it. We have several
> new Mips computers that have been developed in that time and they
> were busy with those projects.
> 
> It was about to get finally pushed upstream and then this new port appeared.
> 
> I would like to still submit our patches .
> 
> Please advise.
> 
> Out port is complete and already tested to a level which would be
> difficult for someone else to do that does not have access to our
> AVP test suite.
> 

The best help would be to help getting the patches submitted by Jia Liu
to get integrated in QEMU. For that a code review would be appreciated,
but the best you can do is probably to pass the AVP test suite on them.

The patches can be found there:

 http://lists.nongnu.org/archive/html/qemu-devel/2012-09/msg04818.html

Aurelien

-- 
Aurelien Jarno                          GPG: 1024D/F1BCDB73
aurelien@aurel32.net                 http://www.aurel32.net

Re: [Qemu-devel] MIPS DSP for Qemu

[Johnson, Eric]

> -----Original Message-----
> From: qemu-devel-bounces+ericj=mips.com@nongnu.org [mailto:qemu-devel-
> bounces+ericj=mips.com@nongnu.org] On Behalf Of Peter Maydell
> Sent: Friday, October 05, 2012 8:07 AM
> To: Kotler, Reed
> Cc: Lau, David; Fuhler, Rich; Gilmore, Douglas; qemu-devel@nongnu.org; Jia
> Liu
> Subject: Re: [Qemu-devel] MIPS DSP for Qemu
> 
> On 3 October 2012 22:37, reed kotler <rkotler@mips.com> wrote:
> > A year and half ago, I did a complete implementation  for Mips DSP in
> Qemu.
> > My port has passed all the MIPS AVPs (Architectural Verification
> Programs)
> > for DSP, which is something not available to the public but is what all
> > architectural licenses and internal groups are required to pass.
> 
> > It was about to get finally pushed upstream and then this new port
> appeared.
> 
> ...you could have mentioned this back in March when Jia first sent
> his DSP related patches...

Reed only recently became aware of Jia's patches.  Reed's implementation had gone through a few rounds of cleanup based on feedback from a third party.  That work was not completed.  There is still more cleanup that needs to be done.  Unfortunately the resources which might have worked on it were and still are involved in higher priority tasks.

At this point it probably makes sense to just address an issues with Jia's patches for the MIPS32 and MIPS64 architecture encodings.  microMIPS instruction encodings will need to be added.

> > I would like to still submit our patches .
> >
> > Please advise.
> 
> Well, if your patches are in what you believe to be a clean and
> ready-for-upstream state anyway, you might as well submit them to
> the mailing list so we can look at them. (you might want to read
> http://wiki.qemu.org/Contribute/SubmitAPatch if you haven't already.)
> 
> I also note that target-mips/ is currently in the "Odd Fixes"
> maintenance state -- is anybody at MIPS in a position to step
> up and help with bug fixing and patch review of that area?

MIPS has been considering several options to address the issue of a MIPS target maintainer for QEMU.

Since the topic has come up, what is the process for vetting a maintainer?

-Eric

Re: [Qemu-devel] MIPS DSP for Qemu

[Peter Maydell]

On 8 October 2012 18:19, Johnson, Eric <ericj@mips.com> wrote:
> Peter Maydell wrote:
>> I also note that target-mips/ is currently in the "Odd Fixes"
>> maintenance state -- is anybody at MIPS in a position to step
>> up and help with bug fixing and patch review of that area?
>
> MIPS has been considering several options to address the issue of
> a MIPS target maintainer for QEMU.
>
> Since the topic has come up, what is the process for vetting a
> maintainer?

Well, I can tell you the process I went through in becoming a
co-maintainer for the ARM target (about a year or so ago now).
Basically I started out by doing a bunch of work that seemed
to need doing and that nobody else was doing at the time:
 * submitting patches to fix various bugs
 * reviewing patches other people sent to the list
 * generally taking part in discussions on list and irc
 * collecting up patches and making sure they didn't get
   forgotten
 * progressing to putting together a tree and starting to
   send pull-request emails
and about the last thing was getting the MAINTAINERS file
changed to add my name.
If there was a formal vetting process I didn't notice it :-)

My take on it is that you can begin to get done the things
you want done as "just another contributor". While you're
doing that you gradually build up trust and credibility with
the community that (a) you're going to hang around for a while
and not just pop in every three months with a new pile of patches
(b) your code is generally technically good and (c) that you
would do a good job with the other aspects of being a subsystem
maintainer (eg won't just throw any old rubbish into the tree,
ignore review comments, or only look at your own patches and
not other peoples'). Then it kind of gradually fades from
'we're going to review everything first and apply it by hand'
to pull requests being applied fairly automatically.

The distributed nature of git means there isn't a sharp dividing
line between 'maintainer' and 'somebody who does most of the work
in this area of the code'. I found getting the 'maintainer'
title didn't really mean a change in what I could get
changed/fixed in the code; it just makes some things a little
smoother and quicker administratively.

-- PMM

Re: [Qemu-devel] MIPS DSP for Qemu

[陳韋任 (Wei-Ren Chen)]

> > Since the topic has come up, what is the process for vetting a
> > maintainer?
> 
> Well, I can tell you the process I went through in becoming a
> co-maintainer for the ARM target (about a year or so ago now).
> Basically I started out by doing a bunch of work that seemed
> to need doing and that nobody else was doing at the time:
>  * submitting patches to fix various bugs
>  * reviewing patches other people sent to the list
>  * generally taking part in discussions on list and irc
>  * collecting up patches and making sure they didn't get
>    forgotten
>  * progressing to putting together a tree and starting to
>    send pull-request emails
> and about the last thing was getting the MAINTAINERS file
> changed to add my name.
> If there was a formal vetting process I didn't notice it :-)

  This could be put on wiki page so that people who want to be a
maintainer know what they should do. :)

Regards,
chenwj

-- 
Wei-Ren Chen (陳韋任)
Computer Systems Lab, Institute of Information Science,
Academia Sinica, Taiwan (R.O.C.)
Tel:886-2-2788-3799 #1667
Homepage: http://people.cs.nctu.edu.tw/~chenwj