From eda0ba38a8dfd2572089bd229a027d497c340158 Mon Sep 17 00:00:00 2001 From: Heiko Schocher Date: Mon, 4 Nov 2013 14:04:59 +0100 Subject: bootcount: store bootcount var in environment If no softreset save registers are found on the hardware "bootcount" is stored in the environment. To prevent a saveenv on all reboots, the environment variable "upgrade_available" is introduced. If "upgrade_available" is 0, "bootcount" is always 0 therefore no need to save the environment on u-boot boot, if "upgrade_available" is 1 "bootcount" is incremented in the environment and environment gets written on u-boot start. So the Userspace Applikation must set the "upgrade_available" and "bootcount" variable to 0 (for example with fw_setenv), if a boot was successfully. Signed-off-by: Heiko Schocher --- README | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) (limited to 'README') diff --git a/README b/README index a70475f..39b3fe6 100644 --- a/README +++ b/README @@ -784,6 +784,22 @@ The following options need to be configured: as a convenience, when switching between booting from RAM and NFS. +- Bootcount: + CONFIG_BOOTCOUNT_LIMIT + Implements a mechanism for detecting a repeating reboot + cycle, see: + http://www.denx.de/wiki/view/DULG/UBootBootCountLimit + + CONFIG_BOOTCOUNT_ENV + If no softreset save registers are found on the hardware + "bootcount" is stored in the environment. To prevent a + saveenv on all reboots, the environment variable + "upgrade_available" is used. If "upgrade_available" is + 0, "bootcount" is always 0, if "upgrade_available" is + 1 "bootcount" is incremented in the environment. + So the Userspace Applikation must set the "upgrade_available" + and "bootcount" variable to 0, if a boot was successfully. + - Pre-Boot Commands: CONFIG_PREBOOT -- cgit v1.1