On 13/07/2018 14.34, Martin Hundebøll wrote:
The existing bootcount feature is targeted systems with a primary, and a
rescue boot setup, where the number of boot tries to the primary boot is
tracked. If the number exceeds the limit, the alternative/rescue is
booted.
This patch adds support for a more sophisticated setup, where more than
two boot slots can exist, and the order of slots can be configured.
The 'bootcommand' command reads the configured slots (and their
priority/order) from a configured environment variable ("bootslots" by
default). For each conifgured slot, a remaining boot count is maintained
in an evnironment variable ("bootcount_<slot>" by default). If the first
boot slot has positive boot count, it is booted using the slot specific
boot command ("bootcmd_<slot>" by default). Otherwise the next slot is
checked.
An example environment when using the bootslot command with two slots
("a" and "b"):
bootslots=a b
bootcount_a=3
bootcount_b=3
bootcmd_a=setenv bootargs $bootargs root=/dev/mmcblk0p1; booti $loadaddr
bootcmd_b=setenv bootargs $bootargs root=/dev/mmcblk0p2; booti $loadaddr
Once linux is booted, it resets the bootcount variable for the booted
slot using "fw_setenv":
fw_setenv bootcount_a 3
When the non-booted slot is updated, the order is updated by setting the
bootslots variable with "fw_setenv":
fw_setenv bootslots=b a
Signed-off-by: Martin Hundebøll <[email protected]>
Tested-by: Sean Nyekjaer <[email protected]>
We have used this for the past 1.5 years.
Will you post this as a patch?
/Sean
