[yocto] What criteria are categorized? (tmp/work/...)

[Patrick Ohly]

On Tue, 2016-11-29 at 17:15 +1300, Paul Eggleton wrote:
> On Tue, 29 Nov 2016 11:47:40 윤영석 wrote:
> > After poky the build, i look at the tmp/work folder.
> > I can see these folders.
> > All-poky-linux / i586-poky-linux / qemux86-poky-linux / x86_64-linux /
> > 
> > What is the classification of each folder?
> 
> That directory level corresponds to MULTIMACH_TARGET_SYS, whose value is
> "${PACKAGE_ARCH}${TARGET_VENDOR}-${TARGET_OS}". The first variable
> PACKAGE_ARCH has a default value of "${TUNE_PKGARCH}" which makes a recipe
> architecture-specific by default. PACKAGE_ARCH is often set in the recipe
> in two common cases:
> 
> 1) Recipes which are packaging something that is not architecture-specific -
> these should "inherit allarch" which will automatically set
> PACKAGE_ARCH = "all". Note that in this situation you should use
> "inherit allarch" rather than setting PACKAGE_ARCH yourself since that is
> not the only thing that the allarch class takes care of.
> 
> 2) Recipes which are packaging something that is machine-specific - these
> should set PACKAGE_ARCH = "${MACHINE_ARCH}".

That's three cases - "all archictures", "machine", "target archicture",
which makes sense. For example, linux-yocto and base-files are
machine-specific and thus in qemux86-poky-linux.

But when using meta-intel and MACHINE=intel-corei7-64 (at least in Ostro
OS, haven't tried with Poky), the kernel ends up in
corei7-64-intel-common-ostro-linux together with gnu-efi and
intel-microcode, while base-files and the other machine specific recipes
are in intel_corei7_64-ostro-linux.

For qemux86 and linux-yocto, PACKAGE_ARCH=MACHINE_ARCH="qemux86".
For intel-corei7-64 and linux-yocto,
PACKAGE_ARCH=INTEL_COMMON_PACKAGE_ARCH="corei7-64-intel-common" (from
meta-intel/conf/machine/include/intel-common-pkgarch.inc).

I suppose that's because the same kernel can be used by multiple
machines, so there's basically a forth level of sharing.

I just wish that the naming of the resulting directories was a bit more
intuitive. I'm constantly wondering what's in
"corei7-64-intel-common-ostro-linux" and what's in
"intel_corei7_64-ostro-linux" :-/

-- 
Best Regards, Patrick Ohly

The content of this message is my personal opinion only and although
I am an employee of Intel, the statements I make here in no way
represent Intel's position on the issue, nor am I authorized to speak
on behalf of Intel on this matter.