armv6 tree vs. buildkernel

[Tim Kientzle]

On Jun 23, 2012, at 12:58 PM, Warner Losh wrote:

> 
> On Jun 23, 2012, at 12:58 PM, Tim Kientzle wrote:
>> On Jun 23, 2012, at 7:35 AM, Warner Losh wrote:
>>> 
>>>> P.S.  How is CPUTYPE/TARGET_CPUTYPE supposed to be inferred for regular "buildworld"?
>>>> The only option I can find is to set it explicitly in /etc/src.conf
>>> 
>>> It can't possibly work very well.  We need to get TARGET_ARCH=armv6 working instead of continuing these kludges.
>> 
>> 
>> Help get me oriented and I'll start grinding through this.
>> 
>> What values of TARGET_ARCH should be supported?
> 
> arm, armeb, armv6 (and maybe armv6eb if they make those).

So do you consider the -DARM_ARCH_6  and -D_ARM_ARCH_6
defines to be among these "kluges"?

How should the C source identify the architecture and
customize itself?

I'm trying to get a clearer picture of how this *should*
work before I start roto-tilling a lot of code.

>> Right now, there are ARCH values of arm and armeb.
>> Should there be armv6eb?  armv7?
> 
> There should be no armv7, since armv6 means v6 and later.  At some point there will be an arm64, I suppose too.

So if someone wants an armv7 tree, they should have
  TARGET=arm
  TARGET_ARCH=armv6
  TARGET_CPUTYPE=armv7

>> I'm also unclear on the distinction between make's MACHINE_ARCH
>> and uname -p; are these supposed to be the same?  If so, shouldn't
>> make be using a sysctl instead of a hard-coded value?
> 
> I thought it already did.  That might not be a bad idea.  MACHINE_ARCH and uname -p should be identical.  If they aren't, that's a bug.

Ah.  That helps.  (This certainly isn't true in the current
make source and I can't find where this assumption
is documented.)

> I posted patches here before to do all (most?) of MACHINE_ARCH=armv6.  Have you tried them on the armv6 branch?  I've not had a chance to port them over yet.

I've seen some oblique references to those patches but
haven't tracked them down to study yet.

Is this r234548 in users/imp?

Tim