[OE-core] [PATCH] soc-family: fix SOC_FAMILY override order

[Maupin, Chase]

> -----Original Message-----
> From: otavio.salvador at gmail.com
> [mailto:otavio.salvador at gmail.com] On Behalf Of Otavio Salvador
> Sent: Saturday, March 09, 2013 6:11 AM
> To: Maupin, Chase
> Cc: Denys Dmytriyenko; Patches and discussions about the oe-core
> layer
> Subject: Re: [OE-core] [PATCH] soc-family: fix SOC_FAMILY
> override order
> 
> On Fri, Mar 8, 2013 at 7:16 PM, Maupin, Chase
> <chase.maupin at ti.com> wrote:
> >> -----Original Message-----
> >> From: otavio.salvador at gmail.com
> >> [mailto:otavio.salvador at gmail.com] On Behalf Of Otavio
> Salvador
> >> Sent: Friday, March 08, 2013 2:27 PM
> >> To: Denys Dmytriyenko
> >> Cc: Maupin, Chase; Patches and discussions about the oe-core
> >> layer
> >> Subject: Re: [OE-core] [PATCH] soc-family: fix SOC_FAMILY
> >> override order
> >>
> >> On Fri, Mar 8, 2013 at 5:06 PM, Denys Dmytriyenko
> >> <denis at denix.org> wrote:
> >> > On Fri, Mar 08, 2013 at 03:52:57PM -0300, Otavio Salvador
> >> wrote:
> >> >> On Fri, Mar 8, 2013 at 2:51 PM, Chase Maupin
> >> <Chase.Maupin at ti.com> wrote:
> >> >> > * the current order has SOC_FAMILY settings, which are
> >> generic
> >> >> >   settings for a group of devices, overriding the machine
> >> specific
> >> >> >   settings.  For example:
> >> >> >
> >> >> >   KERNEL_DEVICETREE_ti33x = "xxxx"
> >> >> >   KERNEL_DEVICETREE_beaglebone = "yyyy"
> >> >> >
> >> >> >   Should yield "yyyy" when building for the beaglebone
> >> because
> >> >> >   that is a more specific device than ti33x.  However,
> >> without this
> >> >> >   change the result is that the value is set to "xxxx"
> >> meaning the
> >> >> >   more generic setting overrides the more specific
> setting.
> >> >> >
> >> >> > Signed-off-by: Chase Maupin <Chase.Maupin at ti.com>
> >> >>
> >> >> Maybe while on that you could look at supporting xx:yy as
> SoC
> >> family?
> >> >> like am37xx:am3715 ?
> >> >
> >> > Did you mean am3517? That's a slightly different variant of
> >> am35x/omap35x SoC.
> >>
> >> Yes; sorry ... what I meant was 'am35xx:am3517'
> >>
> >> > But if you really meant am3715 (as well as am3705, am3725
> and
> >> am3730), then
> >> > those are variants of am37x SoC, just with some subsystems,
> >> like SGX or DSP,
> >> > being absent or present. Having those variants handled by
> >> SOC_FAMILY would be
> >> > an overkill. Instead, we've started using MACHINE_FEATURES
> to
> >> distinguish
> >> > between those variants of the same SoC, by checking for
> "sgx"
> >> and/or "dsp"
> >> > flags there and pulling in needed software components
> >> accordingly.
> >>
> >> My main concern here is that COMPATIBLE_MACHINE also parses
> >> SOC_FAMILY
> >> however if you have two (as the 'am35xx:am3517') it is going
> to
> >> fail;
> >> it could split it and parse it individually.
> >
> > Sorry, I'm not sure if I'm following here.  Are you saying you
> would find it useful to have support for a MACHINE to have more
> than one SOC_FAMILY?  In the example above I would have expected
> that you would have a machine config file for am3517 which has an
> SOC_FAMILY of am35xx.  Why would you specify two SOC_FAMILY
> values per machine?
> 
> We can have more generic to more specific combinations.
> 
> > Or are you trying to build something like omap3->am35xx->am3517
> where you can use omap3 as a more generic setting but still use
> am35xx for a slightly more restrictive group that is still
> grouping like parts, and finally you use am3517 for the exact
> part?
> 
> Exactly so we avoid duplication stuff to boards or SoCs. Another
> example of use: imx -> mx6q -> mx6.

I see.  This could be of some use and I'll play with it.  This should not be required though for this patch since right now I want to fix the order issue.  Any objection to the patch as is?

> 
> --
> Otavio Salvador                             O.S. Systems
> E-mail: otavio at ossystems.com.br  http://www.ossystems.com.br
> Mobile: +55 53 9981-7854
> http://projetos.ossystems.com.br