Why I did it
The S3IP (Simplified Switch System INtegration Program) sysfs specification defines a unified interface to access peripheral hardware on devices from different vendors, making it easier for SONiC to support different devices and platforms.
PDDF is a framework to simplify the driver and SONiC platform APIs development for new platforms. This effort is first step in combining the two frameworks.
This specific PR adds support for pddf-s3ip-init.service and enables it in PDDF.
Why I did it
Some platforms need to run few steps before the PDDF service is actually started.
* Adding pre_pddf_init script in the service file
* Raising exception for get_target_speed() for PSU-fan in PDDF (#8129)
This change introduces PDDF which is described here: https://github.com/Azure/SONiC/pull/536
Most of the platform bring up effort goes in developing the platform device drivers, SONiC platform APIs and validating them. Typically each platform vendor writes their own drivers and platform APIs which is very tailor made to that platform. This involves writing code, building, installing it on the target platform devices and testing. Many of the details of the platform are hard coded into these drivers, from the HW spec. They go through this cycle repetitively till everything works fine, and is validated before upstreaming the code.
PDDF aims to make this platform driver and platform APIs development process much simpler by providing a data driven development framework. This is enabled by:
JSON descriptor files for platform data
Generic data-driven drivers for various devices
Generic SONiC platform APIs
Vendor specific extensions for customisation and extensibility
Signed-off-by: Fuzail Khan <fuzail.khan@broadcom.com>
