Allow master image to track the SD card it's using

Registered by Zygmunt Krynicki on 2012-03-26

Currently all boards we are interested in have a working mmc controller. SD specification defines the CID register that contains per-card unique identification numbers. The actual syntax of the register is irrelevant but if made available from the master image could be used to track and identify SD cards in a particular lava installation.

A master image could detect when a post-first-boot image was copied to another card (thus breaking uniqueness of first-boot-uuid). LAVA device manager could track the wear of each card even if it was moved from board to board without explicit notification done manually by the system administrator. The device manager could also track SD card performance as experienced by different devices in different master images. This could be used as basis for additional argument to timeout expressions it dispatcher jobs.

Blueprint information

Status:
Not started
Approver:
Paul Larson
Priority:
Undefined
Drafter:
Zygmunt Krynicki
Direction:
Needs approval
Assignee:
Andy Doan
Definition:
Discussion
Series goal:
None
Implementation:
Not started
Milestone target:
milestone icon backlog

Related branches

Sprints

Whiteboard

The register is trivial to read from userspace:

see /sys/block/mmc*/device/cid

(?)

Work Items

Work items:
Create lava-mmc-info tool and in master-rootfs-extras: TODO
Add ability to enumerate MMC cards (both emmc and regular mmc): TODO
Add ability to query and display the CID register of each card: TODO

This blueprint contains Public information 
Everyone can see this information.