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 <hs@denx.de>

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 <hs@denx.de>
Heiko Schocher · Tom Rini
1 parent 85b8c5c4bf
Showing 3 changed files with 46 additions and 0 deletions Side-by-side Diff
README
drivers/bootcount/Makefile
drivers/bootcount/bootcount_env.c
@@ -784,6 +784,22 @@
 		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
  
@@ -8,4 +8,5 @@
 obj-$(CONFIG_SOC_DA8XX)		+= bootcount_davinci.o
 obj-$(CONFIG_AM33XX)		+= bootcount_davinci.o
 obj-$(CONFIG_BOOTCOUNT_RAM)	+= bootcount_ram.o
+obj-$(CONFIG_BOOTCOUNT_ENV)	+= bootcount_env.o
+/*
+ * (C) Copyright 2013
+ * Heiko Schocher, DENX Software Engineering, hs@denx.de.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+
+void bootcount_store(ulong a)
+{
+	int upgrade_available = getenv_ulong("upgrade_available", 10, 0);
+
+	if (upgrade_available) {
+		setenv_ulong("bootcount", a);
+		saveenv();
+	}
+}
+
+ulong bootcount_load(void)
+{
+	int upgrade_available = getenv_ulong("upgrade_available", 10, 0);
+	ulong val = 0;
+
+	if (upgrade_available)
+		val = getenv_ulong("bootcount", 10, 0);
+
+	return val;
+}
...	...	@@ -784,6 +784,22 @@
784	784	as a convenience, when switching between booting from
785	785	RAM and NFS.
786	786
	787	+- Bootcount:
	788	+ CONFIG_BOOTCOUNT_LIMIT
	789	+ Implements a mechanism for detecting a repeating reboot
	790	+ cycle, see:
	791	+ http://www.denx.de/wiki/view/DULG/UBootBootCountLimit
	792	+
	793	+ CONFIG_BOOTCOUNT_ENV
	794	+ If no softreset save registers are found on the hardware
	795	+ "bootcount" is stored in the environment. To prevent a
	796	+ saveenv on all reboots, the environment variable
	797	+ "upgrade_available" is used. If "upgrade_available" is
	798	+ 0, "bootcount" is always 0, if "upgrade_available" is
	799	+ 1 "bootcount" is incremented in the environment.
	800	+ So the Userspace Applikation must set the "upgrade_available"
	801	+ and "bootcount" variable to 0, if a boot was successfully.
	802	+
787	803	- Pre-Boot Commands:
788	804	CONFIG_PREBOOT
789	805
...	...	@@ -8,4 +8,5 @@
8	8	obj-$(CONFIG_SOC_DA8XX) += bootcount_davinci.o
9	9	obj-$(CONFIG_AM33XX) += bootcount_davinci.o
10	10	obj-$(CONFIG_BOOTCOUNT_RAM) += bootcount_ram.o
	11	+obj-$(CONFIG_BOOTCOUNT_ENV) += bootcount_env.o
	1	+/*
	2	+ * (C) Copyright 2013
	3	+ * Heiko Schocher, DENX Software Engineering, hs@denx.de.
	4	+ *
	5	+ * SPDX-License-Identifier: GPL-2.0+
	6	+ */
	7	+
	8	+#include <common.h>
	9	+
	10	+void bootcount_store(ulong a)
	11	+{
	12	+ int upgrade_available = getenv_ulong("upgrade_available", 10, 0);
	13	+
	14	+ if (upgrade_available) {
	15	+ setenv_ulong("bootcount", a);
	16	+ saveenv();
	17	+ }
	18	+}
	19	+
	20	+ulong bootcount_load(void)
	21	+{
	22	+ int upgrade_available = getenv_ulong("upgrade_available", 10, 0);
	23	+ ulong val = 0;
	24	+
	25	+ if (upgrade_available)
	26	+ val = getenv_ulong("bootcount", 10, 0);
	27	+
	28	+ return val;
	29	+}