[yocto] i486sx machine porting from oe-classic

[Andrea Galbusera]

Hi,

In oe-classic there used to be a machine configuration for an i486sx
based machine called vortex86sx. In the past I was successful in
building a running image for such a target. Since I'd like to make a
new system based on vortex, my goal is to leverage the whole Yocto
Project infrastructure and port that old configuration to a BSP layer.
This will save me a lot of time in supporting developers with SDKs and
so.

Since I could not find any BSP based on hardware older than i586 in
recent Yocto trees, I'm concerned about this. Do you know of any
obstacle in doing such a port? I'm mainly interested in building
images with no graphics for that target: core-image-minimal is a
reasonable reference for me.

My plan was to initially lay out a new BSP by following guidelines
from Development Manual and BSP Guide. Then, what I suspect to be a
little trickier for my expertise, is the porting of the original
tune-i486sx.inc file to the current Yocto infrastructure. Is there any
document I can leverage to map the variables defined in the
oe-classic's syntax to the current ones for such a machine
configuration file?

The original i486 tune file was defining the following:

TARGET_ARCH = "i486"
TARGET_CC_ARCH = "-march=i486"
PACKAGE_EXTRA_ARCHS = "486sx"
BASE_PACKAGE_ARCH = "486sx"
FEED_ARCH = "${BASE_PACKAGE_ARCH}"

Are they still valid variables? Do I need any more?

Thank you in advance. Regards,
Andrea