control agent can now uboot commands

docs/uboot.md

@@ -1,4 +1,4 @@
-Booting release image with bootusb
+## Booting release image with bootusb
  - Use this if you are flashing image from macos/flashusb.sh
 ```
 setenv bootusb '
@@ -18,8 +18,16 @@ setenv bootusb 'usb start; ext4load usb 0:2 ${mks_loadaddr} /boot/kernel.itb; bo
 run bootusb
 ```
 
+## Run fw_printenv and fw_setenv from kubectl
+```
+# Avoid using daemonset/control-agent if you have multiple nodes
+kubectl exec -n kube-system control-agent-abcdef1 -- /ctl internal fw-setenv --key foo --value bar
 
-Original uboot env from mono
+# fw_printenv
+kubectl exec -n kube-system ds/control-agent -- /ctl internal fw-printenv --key foo
+```
+
+## Original uboot env from mono
 ```
 arch=arm
 baudrate=115200