[Buildroot] [PATCH v2 3/3] pru-sample: add sample PRU application

[Thomas Petazzoni <thomas.petazzoni@free-electrons.com>]

Hello,

On Sun, 27 Nov 2016 07:41:23 -0500, Ash Charles wrote:

> >  The intention here was not to create a new package, but rather to allow the
> > installation of the examples provided in pru-software-support. I.e. add a config
> > option "PRU_SOFTWARE_SUPPORT_INSTALL_EXAMPLES". Or rather, add a
> > pru-software-support target package for the examples (the firmware files are to
> > be installed on the target so it has to be a target package).  
> Okay.  How best to implement this?  Currently, I have
> PRU_SOFTWARE_SUPPORT as a host package (Config.in.host) as previously
> discussed. 

Why is pru-software-support a host package? It really builds/installs
things for the target, even if the target is the PRU and not the ARM.

Was it made a host tool after a discussion with Arnout?

> In the same directory, I can add a PRU_SOFTWARE_EXAMPLES
> Config.in for a target package that depends on the host package i.e. a
> user will select PRU support and then, if they wish, can choose to
> include the examples pack for their target.  Then, I just need to add
> some steps to the existing makefile to build out the examples too.

I would say pru-software-support should be a target package, with the
main option installing the "libraries", and a sub-option to enable the
examples.

> >  Obviously, only 1 firmware binary can be installed. So you have the following
> > options:
> > - Support only one example.
> > - Add config options for all the examples and let the user select it.
> > - Install examples, but not as am335x-pru0-fw, but in a pru-examples
> > subdirectory, leaving it up to the user to copy/link it to the correct name for
> > firmware loading. Mention in the help text how to do that.  
> What is the best place for the examples directory tree to be installed
> /opt/pru-examples?

/usr/share/pru-software-support/ I'd say.

> Is it reasonable to support users who wish to select their desired
> example firmware before filesystem creation (firmware can be loaded
> directly on boot & maybe they have a read-only rootfs) rather than on
> first boot?  I think this means they'd have to make the copy in the
> output/target directory and then rerun make to finalize the rootfs.
> What is the best way to give a user instructions? (Sorry for all the
> questions...buildroot neophyte)

You can give some details by writing a readme.txt in
package/pru-software-support/.

Best regards,

Thomas
-- 
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com