Linux Plumbers Embedded microconference

Linux Plumbers Embedded microconference

[Grant Likely]

I'm now getting around to drafting the agenda for the embedded
microconference.  From looking at the proposals and some of the recent
mailing list discussions, there are some topics that bubble up to the
surface for me:

1) Device model usage - Support for runtime PM has been a hot topic,
but the way the device model is populated and used on embedded
platforms also has impact on correct initialization ordering, and how
to instantiate 'system' devices composed of multiple discrete devices
across the system.  ie. connecting a codec and a DAI in ASoC.

2) Device Tree, HWMOD, static pdata, SFI, and other methods for
teaching the kernel about the machine.

3) Common infrastructure beyond the kernel.  Android has fastboot and
other tools.  Many folks use u-boot for development, but something
custom (smaller) for deployment.  Are there any other tools/techniques
from Android/MeeGo/Linaro/WebOS/etc. that would be useful to a wider
audience.  Tim Bird has offered to lead this discussion.

4) Asymmetric multiprocessing (AMP) intercommunication.  Cores are
cheap, hardware is built with lots of them but how do they
communicate?  This is an issues for DSPs and for embedded
virtualization.  Syslink has been proposed.  Freescale PowerPC has
multicore chips that can be carved up for AMP.  Patches have been
circulated to repurpose virtio for interprocessor communication.

...

1 & 2 are somewhat interrelated as they are both aspects of embedded
requirements on the device model.  I'm not sure, but I may end up
merging these two topics to a degree.  My impression is that the same
problems are being wrestled with in different problem domains.  I'd
like to schedule 3 or 4 people to give a brief (10-15min) overview of
how they need devices registered, and how it fits in with the driver
model, followed by discussion.  Hopefully it will identify areas where
common solution can/should be implemented.  Or in other words; take
our own blinders off for a bit and see how other people are solving
the same problems.  :-)

Here is my draft list:

Kevin: How HWMOD is used to describe interconnections between internal
SoC devices.
Mark or Liam: ASoC - How what needs to be done to collect disparate
devices (codecs, audio controllers, etc) into a single SoC device.
Jeremy: Populating the device model with device tree external data (why and how)
(I'm also open to other suggestions)

Mark and Liam, I know you haven't made a proposal to do this, but if
you'd be willing I think it would be valuable.

...

The AMP IPC topic is interesting to me, but I'd like to get some
feedback before I commit to it.  I would schedule it the same way that
the device model discussion is organized; 3-4 overviews 10-15 minutes
each followed by discussion.  Right now I've got a proposal from the
TI folks to talk about Syslink.  Freescalers, what say you?  Could I
convince one of you to talk about AMP IPC on your powerpc multicore
SoCs?  Multicore on Xilinx FPGAs would also be interesting, but I'm
not up to date on if anybody is actively working on that.  Are there
any other AMP IPC mechanisms that should be discussed?

...

Tim, Jeremy and Kevin; I've accepted your micro-conference topics.  As
the conference gets closer I'll write up a draft of the actual agenda
and your proposals can be massaged appropriately to reflect exactly
what issues will be discussed.

Thoughts?
g.

-- 
Grant Likely, B.Sc., P.Eng.
Secret Lab Technologies Ltd.

Re: Linux Plumbers Embedded microconference

[Mark Brown]

On Fri, Sep 17, 2010 at 05:32:42PM -0600, Grant Likely wrote:

> Mark or Liam: ASoC - How what needs to be done to collect disparate
> devices (codecs, audio controllers, etc) into a single SoC device.

> Mark and Liam, I know you haven't made a proposal to do this, but if
> you'd be willing I think it would be valuable.

I'd certainly be happy to do this, and I imagine Liam would too (he's on
vacation at the minute so it might take him a while to respond).

Re: Linux Plumbers Embedded microconference

[Liam Girdwood]

On Sat, 2010-09-18 at 10:47 +0100, Mark Brown wrote:
> On Fri, Sep 17, 2010 at 05:32:42PM -0600, Grant Likely wrote:
> 
> > Mark or Liam: ASoC - How what needs to be done to collect disparate
> > devices (codecs, audio controllers, etc) into a single SoC device.
> 
> > Mark and Liam, I know you haven't made a proposal to do this, but if
> > you'd be willing I think it would be valuable.
> 
> I'd certainly be happy to do this, and I imagine Liam would too (he's on
> vacation at the minute so it might take him a while to respond).

Yep, that sounds good to me.

Thanks

Liam

-- 
Freelance Developer, SlimLogic Ltd
ASoC and Voltage Regulator Maintainer.
http://www.slimlogic.co.uk

Re: Linux Plumbers Embedded microconference

[Kevin Hilman]

Grant Likely <grant.likely@secretlab.ca> writes:

> I'm now getting around to drafting the agenda for the embedded
> microconference.  From looking at the proposals and some of the recent
> mailing list discussions, there are some topics that bubble up to the
> surface for me:
>
> 1) Device model usage - Support for runtime PM has been a hot topic,
> but the way the device model is populated and used on embedded
> platforms also has impact on correct initialization ordering, and how
> to instantiate 'system' devices composed of multiple discrete devices
> across the system.  ie. connecting a codec and a DAI in ASoC.
>
> 2) Device Tree, HWMOD, static pdata, SFI, and other methods for
> teaching the kernel about the machine.
>
> 3) Common infrastructure beyond the kernel.  Android has fastboot and
> other tools.  Many folks use u-boot for development, but something
> custom (smaller) for deployment.  Are there any other tools/techniques
> from Android/MeeGo/Linaro/WebOS/etc. that would be useful to a wider
> audience.  Tim Bird has offered to lead this discussion.
>
> 4) Asymmetric multiprocessing (AMP) intercommunication.  Cores are
> cheap, hardware is built with lots of them but how do they
> communicate?  This is an issues for DSPs and for embedded
> virtualization.  Syslink has been proposed.  Freescale PowerPC has
> multicore chips that can be carved up for AMP.  Patches have been
> circulated to repurpose virtio for interprocessor communication.
>
> ...
>
> 1 & 2 are somewhat interrelated as they are both aspects of embedded
> requirements on the device model.  I'm not sure, but I may end up
> merging these two topics to a degree.  My impression is that the same
> problems are being wrestled with in different problem domains.  I'd
> like to schedule 3 or 4 people to give a brief (10-15min) overview of
> how they need devices registered, and how it fits in with the driver
> model, followed by discussion.  Hopefully it will identify areas where
> common solution can/should be implemented.  Or in other words; take
> our own blinders off for a bit and see how other people are solving
> the same problems.  :-)
>
> Here is my draft list:
>
> Kevin: How HWMOD is used to describe interconnections between internal
> SoC devices.

For omap_hwmod, I would like Paul Walmsley (Cc'd) to lead this
discussion (or co-present) as he is the primary author and maintainer of
this for linux-omap.

Paul is planning to be at LPC already, so one or both of us will take
care of it.

Thanks for putting this together,

Kevin

Re: Linux Plumbers Embedded microconference

[Tim Bird]

On 09/17/2010 04:32 PM, Grant Likely wrote:
> 3) Common infrastructure beyond the kernel.  Android has fastboot and
> other tools.  Many folks use u-boot for development, but something
> custom (smaller) for deployment.  Are there any other tools/techniques
> from Android/MeeGo/Linaro/WebOS/etc. that would be useful to a wider
> audience.  Tim Bird has offered to lead this discussion.
..
> Tim, Jeremy and Kevin; I've accepted your micro-conference topics.  As
> the conference gets closer I'll write up a draft of the actual agenda
> and your proposals can be massaged appropriately to reflect exactly
> what issues will be discussed.
> 
> Thoughts?

Sounds good.  I'm going to initiate discussion of this at the
embedded Linux summit coming up next week.  That should help find
the possible areas of wider collaboration, that we can discuss
more at Plumbers.
 -- Tim

=============================
Tim Bird
Architecture Group Chair, CE Linux Forum
Senior Staff Engineer, Sony Network Entertainment
=============================

Re: Linux Plumbers Embedded microconference

[Grant Likely]

On Mon, Sep 20, 2010 at 10:14:43AM -0700, Kevin Hilman wrote:
> Grant Likely <grant.likely@secretlab.ca> writes:
> > Here is my draft list:
> >
> > Kevin: How HWMOD is used to describe interconnections between internal
> > SoC devices.
> 
> For omap_hwmod, I would like Paul Walmsley (Cc'd) to lead this
> discussion (or co-present) as he is the primary author and maintainer of
> this for linux-omap.
> 
> Paul is planning to be at LPC already, so one or both of us will take
> care of it.
> 
> Thanks for putting this together,

Excellent.  We'll discuss details later (after I get back from
travelling this week and next).

g.

Re: Linux Plumbers Embedded microconference

[Kevin Hilman]

On Fri, 2010-09-17 at 17:32 -0600, Grant Likely wrote:
> I'm now getting around to drafting the agenda for the embedded
> microconference.  From looking at the proposals and some of the recent
> mailing list discussions, there are some topics that bubble up to the
> surface for me:
> 
> 1) Device model usage - Support for runtime PM has been a hot topic,
> but the way the device model is populated and used on embedded
> platforms also has impact on correct initialization ordering, and how
> to instantiate 'system' devices composed of multiple discrete devices
> across the system.  ie. connecting a codec and a DAI in ASoC.
> 
> 2) Device Tree, HWMOD, static pdata, SFI, and other methods for
> teaching the kernel about the machine.
> 
> 3) Common infrastructure beyond the kernel.  Android has fastboot and
> other tools.  Many folks use u-boot for development, but something
> custom (smaller) for deployment.  Are there any other tools/techniques
> from Android/MeeGo/Linaro/WebOS/etc. that would be useful to a wider
> audience.  Tim Bird has offered to lead this discussion.
> 
> 4) Asymmetric multiprocessing (AMP) intercommunication.  Cores are
> cheap, hardware is built with lots of them but how do they
> communicate?  This is an issues for DSPs and for embedded
> virtualization.  Syslink has been proposed.  Freescale PowerPC has
> multicore chips that can be carved up for AMP.  Patches have been
> circulated to repurpose virtio for interprocessor communication.
> 
> ...
> 
> 1 & 2 are somewhat interrelated as they are both aspects of embedded
> requirements on the device model.  I'm not sure, but I may end up
> merging these two topics to a degree.  My impression is that the same
> problems are being wrestled with in different problem domains.  I'd
> like to schedule 3 or 4 people to give a brief (10-15min) overview of
> how they need devices registered, and how it fits in with the driver
> model, followed by discussion.  Hopefully it will identify areas where
> common solution can/should be implemented.  Or in other words; take
> our own blinders off for a bit and see how other people are solving
> the same problems.  :-)
> 
> Here is my draft list:
> 
> Kevin: How HWMOD is used to describe interconnections between internal
> SoC devices.
> Mark or Liam: ASoC - How what needs to be done to collect disparate
> devices (codecs, audio controllers, etc) into a single SoC device.
> Jeremy: Populating the device model with device tree external data (why and how)
> (I'm also open to other suggestions)
> 
> Mark and Liam, I know you haven't made a proposal to do this, but if
> you'd be willing I think it would be valuable.
> 
> ...
> 
> The AMP IPC topic is interesting to me, but I'd like to get some
> feedback before I commit to it.  I would schedule it the same way that
> the device model discussion is organized; 3-4 overviews 10-15 minutes
> each followed by discussion.  Right now I've got a proposal from the
> TI folks to talk about Syslink.  Freescalers, what say you?  Could I
> convince one of you to talk about AMP IPC on your powerpc multicore
> SoCs?  Multicore on Xilinx FPGAs would also be interesting, but I'm
> not up to date on if anybody is actively working on that.  Are there
> any other AMP IPC mechanisms that should be discussed?
> 
> ...
> 
> Tim, Jeremy and Kevin; I've accepted your micro-conference topics.  As
> the conference gets closer I'll write up a draft of the actual agenda
> and your proposals can be massaged appropriately to reflect exactly
> what issues will be discussed.

Hi Grant,

Do you have a draft agenda yet for the microconf?  Specifically, I'd
like to get a better feel for how much time we'll dedicate to each
topic, and therefore be better prepared for the discussions.

Also, some TI folks are asking me if I know whether the AMP topic is
going to be discussed.  TI is actively working on this and would like to
participate in any discussions.  Their 1st generation code for this is
in staging (tidspbridge) while the 2nd generation is under active
deveopment with some of the lead developers planning to be at LPC.

Kevin

Re: Linux Plumbers Embedded microconference

[Grant Likely]

On Fri, Oct 15, 2010 at 09:20:28AM -0700, Kevin Hilman wrote:
> Hi Grant,
> 
> Do you have a draft agenda yet for the microconf?  Specifically, I'd
> like to get a better feel for how much time we'll dedicate to each
> topic, and therefore be better prepared for the discussions.

Working on it.  RealSoonNow.

> Also, some TI folks are asking me if I know whether the AMP topic is
> going to be discussed.  TI is actively working on this and would like to
> participate in any discussions.  Their 1st generation code for this is
> in staging (tidspbridge) while the 2nd generation is under active
> deveopment with some of the lead developers planning to be at LPC.

Yes, AMP is absolutely on the agenda.  It seems to be a big topic for
a lot of folks.

g.

Re: Linux Plumbers Embedded microconference

[Grant Likely]

Hi all,

Here is a very early draft of the agenda for the embedded track at the
Linux Plumbers Conference on Nov 3-5th.  Don't make any decisions
based on this, and I'll be talking to some of you individually about
the details, but this gives you an idea of what I'm thinking.

http://wiki.linuxplumbersconf.org/2010:embedded_topics

Cheers,
g.

On Fri, Oct 15, 2010 at 9:50 PM, Grant Likely <grant.likely@secretlab.ca> wrote:
> On Fri, Oct 15, 2010 at 09:20:28AM -0700, Kevin Hilman wrote:
>> Hi Grant,
>>
>> Do you have a draft agenda yet for the microconf?  Specifically, I'd
>> like to get a better feel for how much time we'll dedicate to each
>> topic, and therefore be better prepared for the discussions.
>
> Working on it.  RealSoonNow.
>
>> Also, some TI folks are asking me if I know whether the AMP topic is
>> going to be discussed.  TI is actively working on this and would like to
>> participate in any discussions.  Their 1st generation code for this is
>> in staging (tidspbridge) while the 2nd generation is under active
>> deveopment with some of the lead developers planning to be at LPC.
>
> Yes, AMP is absolutely on the agenda.  It seems to be a big topic for
> a lot of folks.
>
> g.
>
>



-- 
Grant Likely, B.Sc., P.Eng.
Secret Lab Technologies Ltd.