patch to prevent inadvertant erasure of environment and allow deliberate erasure

1 files changed, 97 insertions, 0 deletions

diff --git a/recipes-bsp/multitech/u-boot-linux-utils/crc_erase.patch b/recipes-bsp/multitech/u-boot-linux-utils/crc_erase.patch
new file mode 100644
index 0000000..67cd5ef
--- /dev/null
+++ b/recipes-bsp/multitech/u-boot-linux-utils/crc_erase.patch
@@ -0,0 +1,97 @@
+# Print out the CRC's if debugging.
+# Prevent the erasure of the environment.
+# Allow the deliberate erasure of the environment with the
+# clearenv command. 
+diff --git a/src/u_boot.c b/src/u_boot.c
+index e240475..f10eaa3 100644
+--- a/src/u_boot.c
++++ b/src/u_boot.c
+@@ -64,6 +64,8 @@ static int write_uboot_env(const char *device, struct environment *env)
+ 		error("mtd_erase_all %s failed", device);
+ 		return -1;
+ 	}
++	if(env == NULL)
++		return 0;
+ 
+ 	fd = open(device, O_WRONLY);
+ 	if (fd < 0) {
+@@ -213,7 +215,7 @@ static int cmd_setenv(struct environment *env, int argc, char **argv)
+ 	}
+ 
+ 	env->crc = crc32(0, (uint8_t *) env->data, sizeof(env->data));
+-	dbg("crc: 0x%08X", env->crc);
++	dbg("Calculated crc: 0x%08X", env->crc);
+ 	env->flags = 0;
+ 
+ 	tmp = write_uboot_env(MTD_ENV1, env);
+@@ -252,6 +254,7 @@ int main(int argc, char *argv[]) {
+ 	struct environment *env2;
+ 	uint32_t crc1_ok;
+ 	uint32_t crc2_ok;
++        uint32_t mycrc;
+ 
+ 	if (argc <= 1) {
+ 		usage(stderr);
+@@ -301,12 +304,18 @@ int main(int argc, char *argv[]) {
+ 		error("read_uboot_env failed");
+ 		return 1;
+ 	}
+-	dbg("env1 crc: 0x%08X", env1->crc);
++	dbg("env1 stored crc: 0x%08X", env1->crc);
+ 	dbg("env1 flags: %d", env1->flags);
+-	if (crc32(0, (uint8_t *) env1->data, sizeof(env1->data)) == env1->crc) {
++	mycrc = crc32(0, (uint8_t *) env1->data, sizeof(env1->data));
++	if (mycrc == env1->crc) {
+ 		crc1_ok = 1;
+ 	} else {
+-		error("crc does not match on primary env");
++                dbg("env1 stored crc 0x%x, calculated crc 0x%x",env1->crc,mycrc);
++                if(env1->flags != 255)
++			error("crc does not match on env1");
++		else
++                	dbg("uninitialized env1");
++			
+ 		crc1_ok = 0;
+ 	}
+ 
+@@ -315,20 +324,26 @@ int main(int argc, char *argv[]) {
+ 		error("read_uboot_env failed");
+ 		return 1;
+ 	}
+-	dbg("env2 crc: 0x%08X", env2->crc);
++	dbg("env2 stored crc: 0x%08X", env2->crc);
+ 	dbg("env2 flags: %d", env2->flags);
+-	if (crc32(0, (uint8_t *) env2->data, sizeof(env2->data)) == env2->crc) {
++	mycrc = crc32(0, (uint8_t *) env2->data, sizeof(env2->data));
++	if (mycrc == env2->crc) {
+ 		crc2_ok = 1;
+ 	} else {
+-		error("crc does not match on redundant env");
++                dbg("env2 stored crc 0x%x, calculated crc 0x%x",env2->crc,mycrc);
++                if(env2->flags != 255)
++			error("crc does not match on env2");
++		else
++                	dbg("uninitialized env2");
+ 		crc2_ok = 0;
+ 	}
+ 
+ 	if (!crc1_ok && !crc2_ok) {
+-		error("both environments are bad: loading DEFAULT_ENV");
++		error("both environments are bad: not loading DEFAULT_ENV");
+ 		env = env1;
+ 		env->flags = 0;
+ 		memcpy(env->data, DEFAULT_ENV, sizeof(DEFAULT_ENV));
++                exit(1);
+ 	} else if (crc1_ok && !crc2_ok) {
+ 		env = env1;
+ 	} else if (!crc1_ok && crc2_ok) {
+@@ -353,6 +368,9 @@ int main(int argc, char *argv[]) {
+ 		err = cmd_printenv(env, argc, argv);
+ 	} else if (!tokcmp(cmd, "setenv")) {
+ 		err = cmd_setenv(env, argc, argv);
++	} else if (!tokcmp(cmd, "clearenv")) {
++		(void)write_uboot_env(MTD_ENV1, NULL);
++		(void)write_uboot_env(MTD_ENV2, NULL);
+ 	} else {
+ 		usage(stderr);
+ 		exit(1);