Bug 655 - Support linux running on systems with both Libre-SOC and non-Libre-SOC cpus, or cpus with different feature sets
Summary: Support linux running on systems with both Libre-SOC and non-Libre-SOC cpus, ...
Status: CONFIRMED
Alias: None
Product: Libre-SOC's first SoC
Classification: Unclassified
Component: Source Code (show other bugs)
Version: unspecified
Hardware: Other Linux
: --- enhancement
Assignee: Luke Kenneth Casson Leighton
URL:
Depends on:
Blocks:
 
Reported: 2021-07-02 16:16 BST by Jacob Lifshay
Modified: 2021-07-02 16:22 BST (History)
1 user (show)

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Description Jacob Lifshay 2021-07-02 16:16:20 BST 
Look at how Linux is handling a similar thing for Arm64 where just some of the cpus support 32-bit:

https://www.phoronix.com/scan.php?page=news_item&px=Linux-5.14-ARM64

https://lore.kernel.org/patchwork/patch/1436130/

Find callers of system_32bit_el0_cpumask in the kernel and use that as inspiration to do something similar
Comment 1 Luke Kenneth Casson Leighton 2021-07-02 16:22:01 BST 
this would tie in closely with EABI features, yes it's good to see
this going into other ISAs, first, it sets a precedent that can be
followed.