barebox-state: get devicetree from file

Adds a -i/--input argument to barebox-state to allow passing a
devicetree as a file instead of using it from the system.
This can be used for example on systems that do not use device trees
(such as x86) but where we want to use a dtb blob for describing the
state storage and format.

Signed-off-by: Steffen Trumtrar <s.trumtrar@pengutronix.de>
Signed-off-by: Enrico Jorns <ejo@pengutronix.de>
Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Message-Id: <20191024142451.15777-3-a.fatoum@pengutronix.de>
Signed-off-by: Roland Hieber <rhi@pengutronix.de>

3 files changed, 35 insertions, 10 deletions

diff --git a/src/barebox-state.c b/src/barebox-state.c
index 6b166bf..7ac90c6 100644
--- a/src/barebox-state.c
+++ b/src/barebox-state.c
@@ -306,17 +306,36 @@ static int state_set_var(struct state *state, const char *var, const char *val)
 }
 
 
-struct state *state_get(const char *name, bool readonly, bool auth)
+struct state *state_get(const char *name, const char *filename, bool readonly, bool auth)
 {
 	struct device_node *root, *node;
 	struct state *state;
 	int ret;
 
-	root = of_read_proc_devicetree();
-	if (IS_ERR(root)) {
-		pr_err("Unable to read devicetree. %s\n",
-				strerror(-PTR_ERR(root)));
-		return ERR_CAST(root);
+	if (filename) {
+		void *fdt;
+
+		fdt = read_file(filename, NULL);
+		if (!fdt) {
+			pr_err("Unable to read devicetree file '%s'\n",
+			       filename);
+			return ERR_PTR(-ENOENT);
+		}
+
+		root = of_unflatten_dtb(fdt);
+		free(fdt);
+		if (IS_ERR(root)) {
+			pr_err("Unable to read devicetree. %s\n",
+			       strerror(-PTR_ERR(root)));
+			return ERR_CAST(root);
+		}
+	} else {
+		root = of_read_proc_devicetree();
+		if (IS_ERR(root)) {
+			pr_err("Unable to read devicetree. %s\n",
+			       strerror(-PTR_ERR(root)));
+			return ERR_CAST(root);
+		}
 	}
 
 	of_set_root_node(root);
@@ -368,6 +387,7 @@ static struct option long_options[] = {
 	{"get",		required_argument,	0,	'g' },
 	{"set",		required_argument,	0,	's' },
 	{"name",	required_argument,	0,	'n' },
+	{"input",	required_argument,	0,	'i' },
 	{"dump",	no_argument,		0,	'd' },
 	{"dump-shell",	no_argument,		0,	OPT_DUMP_SHELL },
 	{"force",	no_argument,		0,	'f' },
@@ -386,6 +406,7 @@ static void usage(char *name)
 "-g, --get <variable>                      get the value of a variable\n"
 "-s, --set <variable>=<value>              set the value of a variable\n"
 "-n, --name <name>                         specify the state to use (default=\"state\"). Multiple states are allowed.\n"
+"-i, --input <name>                        load the devicetree from a file instead of using the system devicetree.\n"
 "-d, --dump                                dump the state\n"
 "--dump-shell                              dump the state suitable for shell sourcing\n"
 "-f, --force                               do not check for state manipulation via the HMAC\n"
@@ -425,12 +446,13 @@ int main(int argc, char *argv[])
 	bool readonly = true;
 	int pr_level = 5;
 	int auth = 1;
+	const char *dtb = NULL;
 
 	INIT_LIST_HEAD(&sg_list);
 	INIT_LIST_HEAD(&state_list.list);
 
 	while (1) {
-		c = getopt_long(argc, argv, "hg:s:dvn:qf", long_options, &option_index);
+		c = getopt_long(argc, argv, "hg:s:i:dvn:qf", long_options, &option_index);
 		if (c < 0)
 			break;
 		switch (c) {
@@ -481,6 +503,9 @@ int main(int argc, char *argv[])
 			++nr_states;
 			break;
 		}
+		case 'i':
+			dtb = optarg;
+			break;
 		case ':':
 		case '?':
 		default:
@@ -521,7 +546,7 @@ int main(int argc, char *argv[])
 	}
 
 	list_for_each_entry(state, &state_list.list, list) {
-		state->state = state_get(state->name, readonly, auth);
+		state->state = state_get(state->name, dtb, readonly, auth);
 		if (!IS_ERR(state->state) && !state->name)
 			state->name = state->state->name;
 		if (IS_ERR(state->state)) {
diff --git a/src/barebox-state.h b/src/barebox-state.h
index bd89cf4..a0f49a5 100644
--- a/src/barebox-state.h
+++ b/src/barebox-state.h
@@ -1,7 +1,7 @@
 #ifndef __BAREBOX_STATE__
 #define __BAREBOX_STATE__
 
-struct state *state_get(const char *name, bool readonly, bool auth);
+struct state *state_get(const char *name, const char *file, bool readonly, bool auth);
 char *state_get_var(struct state *state, const char *var);
 
 #endif /* __BAREBOX_STATE__ */
diff --git a/src/keystore-blob.c b/src/keystore-blob.c
index f71ff5d..ed6ecb4 100644
--- a/src/keystore-blob.c
+++ b/src/keystore-blob.c
@@ -30,7 +30,7 @@ int keystore_get_secret(const char *name, const unsigned char **key, int *key_le
 	if (!state) {
 		struct state *tmp;
 
-		tmp = state_get(keystore_state_name, true, false);
+		tmp = state_get(keystore_state_name, NULL, true, false);
 		if (IS_ERR(tmp))
 			return  PTR_ERR(tmp);
 		state = tmp;