Description

These two kernel features are required for the serial console to be usable in early userspace of an Allwinner H6 based board - ie, the init process. The debian initramfs loads these modules which is fine when things go well, but you won't get any logs from the init script which is problematic for debugging and/or customizing it.

This made debugging very challenging as I had no way to get output from the board after the kernel had handed control to init.

After this change, the serial console is available and functional by the time init runs, and any logs from init will be output as expected.

Note: I've put these changes into the "next" config, but my testing has been by making these changes to the "current" config as the "next" config wouldn't compile for my board.

Jira reference number [AR-9999]

How Has This Been Tested?

I built an image and booted it on an Orange Pi 3 LTS board. It's very likely my proposed changes aren't relevant for all sunxi boards, and I don't know enough to know whether compiling these modules into the kernel is problematic for boards that don't need this / have this hardware.

Please describe the tests that you ran to verify your changes. Please also note any relevant details for your test configuration.

• [x] I built an image and booted it on an Orange Pi 3 LTS board

Checklist:

• [x] My code follows the style guidelines of this project
• [x] I have performed a self-review of my own code
• [x] I have commented my code, particularly in hard-to-understand areas
• [ ] I have made corresponding changes to the documentation
• [x] My changes generate no new warnings
• [x] Any dependent changes have been merged and published in downstream modules

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