Re: [dpdk-dev] [PATCH] config: change default cache line size for ARMv8 with meson

[Jerin Jacob Kollanukkaran <jerinj@marvell.com>]

> > Please check below thread and patch.
> > 
> > http://mails.dpdk.org/archives/dev/2019-January/122676.html
> > https://patches.dpdk.org/patch/49477/
> > 
> > Debian folks are building like this for the _generic_ image.
> > What ever works for every distros, I am fine with that.
> > 
> > meson configure -Dmachine=default
> > meson build
> > cd build
> > ninja
> > ninja install
> 
> I think we agree on the idea of having different configs
> for unmodified A72 core and generic build working for all.

Yes, I agree. config or some scheme to address the generic and default
usecase.

> The remaining bits to discuss are:
> 	- do we want to use the armv8 config for unmodified A72?
> 	- what should be the name of the generic config?

If all distros following "meson configure -Dmachine=default" scheme
why not follow that to make generic image. i.e when machine=default
set then Cache lize size 128B CL specific stuff be kicked in else
it probe the value based on MIDR from sysfs.


> When digging more the config files in meson, I found this:
> 	
> http://mesonbuild.com/Cross-compilation.html#cross-file-locations
> It says that distros or compilers should provide some config files.
> It means we should check if some standard names are emerging
> and try to follow the same naming, or even re-use existing config
> files.

I think this for cross compilation. if I understand it correctly,
distro folks build arm64 image on arm64 target(not on x86) with generic
images with lowest denominator cpu flags and such that works for all
platforms.

Something similar found in arch linux website for arm64.
https://archlinuxarm.org/platforms/armv8/generic

See Platforms: ARMv8

Anyway I am leaving this decision to distro folks or whoever is expert
in meson based distro build generic creation.


>