Re: [PATCH 3/3] Add basic PowerPC core tune config

[Richard Purdie <richard.purdie@linuxfoundation.org>]

On Tue, 2011-07-26 at 12:15 -0500, Mark Hatle wrote:
> On 7/26/11 12:05 PM, Richard Purdie wrote:
> > On Tue, 2011-07-26 at 11:53 -0500, Mark Hatle wrote:
> >> On 7/26/11 11:36 AM, Richard Purdie wrote:
> >>> On Tue, 2011-07-26 at 09:57 -0500, Mark Hatle wrote:
> >>>> On 7/26/11 7:44 AM, Richard Purdie wrote:
> >>>>> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
> >>>>> ---
> >>>>>  meta/conf/machine/include/powerpc/arch-powerpc.inc |   45 +++++++++++++++++++-
> >>>>>  meta/conf/machine/include/tune-ppc603e.inc         |   12 ++++-
> >>>>>  meta/conf/machine/include/tune-ppce300c2.inc       |   12 ++++-
> >>>>>  meta/conf/machine/include/tune-ppce500.inc         |   13 ++++--
> >>>>>  meta/conf/machine/include/tune-ppce500mc.inc       |   12 ++++-
> >>>>>  meta/conf/machine/include/tune-ppce500v2.inc       |   12 ++++-
> >>>>>  6 files changed, 88 insertions(+), 18 deletions(-)
> >>>>>
> >>>>> diff --git a/meta/conf/machine/include/powerpc/arch-powerpc.inc b/meta/conf/machine/include/powerpc/arch-powerpc.inc
> >>>>> index 17ace32..3f7befb 100644
> >>>>> --- a/meta/conf/machine/include/powerpc/arch-powerpc.inc
> >>>>> +++ b/meta/conf/machine/include/powerpc/arch-powerpc.inc
> >>>>> @@ -1,3 +1,44 @@
> >>>>> -TUNE_ARCH = "powerpc"
> >>>>> +# Power Architecture definition
> >>>>> +# Four defined ABIs, all combinations of:
> >>>>> +# *) Hard/Soft Floating Point
> >>>>> +# *) 32-bit/64-bit
> >>>>> +
> >>>>> +DEFAULTTUNE ?= "powerpc"
> >>>>> +
> >>>>> +TUNEVALID[m32] = "Power ELF32 standard ABI"
> >>>>> +TUNE_CCARGS += "${@bb.utils.contains("TUNE_FEATURES", "m32", "-m32", "", d)}"
> >>>>> +
> >>>>> +TUNEVALID[m32-arch] = "Enable powerpc package architecture"
> >>>>> +TUNE_ARCH .= "${@bb.utils.contains("TUNE_FEATURES", [ "m32-arch" ], "powerpc", "", d)}"
> >>>>> +
> >>>>> +TUNEVALID[m64] = "Power ELF64 standard ABI"
> >>>>> +TUNE_CCARGS += "${@bb.utils.contains("TUNE_FEATURES", "n64", "-m64", "", d)}"
> >>>>> +
> >>>>> +TUNEVALID[m64-arch] = "Enable powerpc64 package architecture"
> >>>>> +TUNE_ARCH .= "${@bb.utils.contains("TUNE_FEATURES", [ "m64-arch" ], "powerpc64", "", d)}"
> >>>>
> >>>> Why m32-arch and m64-arch?  If m32 or m64 is selected then it should mean
> >>>> powerpc or powerpc64.
> >>>
> >>> I've gotten confused here and mixed up TUNE_ARCH and TUNE_PKGARCH but
> >>> there was a reason.
> >>>
> >>> The missing piece is 
> >>>
> >>> TUNE_PKGARCH ?= "${TUNE_ARCH}"
> >>>
> >>> and the trouble comes when a tune file wants to change this only when
> >>> its tune config is in action.
> >>>
> >>> I'm thinking ahead to trying a mixed ppc 32 and 64 bit build where
> >>> TUNE_PKGARCH needs to take on the values for both configs.
> >>
> >> As far as I can tell, in all cases m32 = powerpc and m64 = powerpc64..  There is
> >> no way to mix a build of ppc32 and ppc64 w/o using the multilib code.
> >>
> >> The m32/m64 is the ABI, so only one can be present in the TUNE_FEATURES.. and
> >> passed via gcc through the TUNE_CCARGS.
> > 
> > Ok, say I use tune-ppcXXX and it sets TUNE_PKGARCH:
> > 
> > TUNE_PKGARCH .= "${@bb.utils.contains("TUNE_FEATURES", "ppc603e", "ppc603e", "", d)}"
> > 
> > and I want a multilib config using this as the m32 ABI and also have
> > powerpc64 as my other multilib. I can't select that as it will get
> > TUNE_PKGARCH wrong in the 64 bit case since:
> > 
> > TUNE_PKGARCH ?= "${TUNE_ARCH}"
> > 
> > is overwritten. I guess we could do:
> > 
> > TUNE_PKGARCH = "${@bb.utils.contains("TUNE_FEATURES", "ppc603e", "ppc603e", "${TUNE_ARCH}", d)}"
> 
> ppc603e is the new option.. (lets say for argument it can run in 64-bit mode, in
> reality it can't and is an invalid config....)
> 
> TUNEVALID[ppc603e] = "PowerPC 603e Optimization"
> 
> # Note the TUNE_NAME is used differently from the TUNE_FEATURES
> TUNE_NAME ?= "ppc603e"
> 
> TUNE_FEATURES_ppc603e = "m32 ppc603e"
> TUNE_FEATURES_ppc603e-64 = "m64 ppc603e"
> 
> The if you include the tune-ppc603e.inc the default is the 32-bit version (what
> I'd consider the reasonable default...)  If you wanted the 64-bit version
> instead you'd simply change set the TUNE_NAME to "ppc603e-64" and the properly
> tuned set of features is set for you.
> 
> TUNE_PKGARCH_ppc603e = "ppc603e"
> TUNE_PKGARCH_ppc603e-64 = "ppc603e-64"

The thing is we don't' support the above syntax for TUNE_PKGARCH...

> etc...
> 
> in the default (ppc603e) case, the TUNE_ARCH should always be "powerpc", and in
> the ppc603e-64 case (if manually enabled), it would be "powerpc64"...
> 
> This is what was done in the ARM cases and I believe the core2 case in ia32.

which turns out to be broken :/.

http://git.yoctoproject.org/cgit.cgi/poky-contrib/commit/?h=rpurdie/ml4&id=244e28

is what I'm considering to "fix" this. I guess the config could do:

TUNE_PKGARCH ?= "${@bb.utils.contains("TUNE_FEATURES", "ppc603e-64", "ppc603e-64", "ppc603e", d)}"

as per the x86 case but since this really limits the reuse of any of the
core variables as you might as well do:

AVAILTUNES = "ppc603e ppc603e-64" 

after doing that since TUNE_PKGARCH will be wrong in any other case.

Cheers,

Richard