FIT: Let user specify the configuration to use

The images in FIT images can be opened in two different ways. They
can be either opened directly based on their names in the images/
node or as part of a configuration based on their names in the
corresponding /configuration/ node.

So far we only supported the latter. To prepare supporting the former
we return a cookie belonging to the configuration from
fit_open_configuration() which we use in fit_open_image() to refer
to the desired configuration.

While at it document fit_open_configuration().

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

2 files changed, 38 insertions, 24 deletions

diff --git a/common/bootm.c b/common/bootm.c
index 0ec7584952..3e48ca1d88 100644
--- a/common/bootm.c
+++ b/common/bootm.c
@@ -152,7 +152,7 @@ bool bootm_has_initrd(struct image_data *data)
 		return false;
 
 	if (IS_ENABLED(CONFIG_FITIMAGE) && data->os_fit &&
-	    fit_has_image(data->os_fit, "ramdisk"))
+	    fit_has_image(data->os_fit, data->fit_config, "ramdisk"))
 		return true;
 
 	if (data->initrd_file)
@@ -214,12 +214,12 @@ int bootm_load_initrd(struct image_data *data, unsigned long load_address)
 		return 0;
 
 	if (IS_ENABLED(CONFIG_FITIMAGE) && data->os_fit &&
-	    fit_has_image(data->os_fit, "ramdisk")) {
+	    fit_has_image(data->os_fit, data->fit_config, "ramdisk")) {
 		const void *initrd;
 		unsigned long initrd_size;
 
-		ret = fit_open_image(data->os_fit, "ramdisk", &initrd,
-				     &initrd_size);
+		ret = fit_open_image(data->os_fit, data->fit_config, "ramdisk",
+				     &initrd, &initrd_size);
 
 		data->initrd_res = request_sdram_region("initrd",
 				load_address,
@@ -344,11 +344,12 @@ int bootm_load_devicetree(struct image_data *data, unsigned long load_address)
 		return 0;
 
 	if (IS_ENABLED(CONFIG_FITIMAGE) && data->os_fit &&
-	    fit_has_image(data->os_fit, "fdt")) {
+	    fit_has_image(data->os_fit, data->fit_config, "fdt")) {
 		const void *of_tree;
 		unsigned long of_size;
 
-		ret = fit_open_image(data->os_fit, "fdt", &of_tree, &of_size);
+		ret = fit_open_image(data->os_fit, data->fit_config, "fdt",
+				     &of_tree, &of_size);
 		if (ret)
 			return ret;
 
@@ -591,17 +592,19 @@ int bootm_boot(struct bootm_data *bootm_data)
 
 		data->os_fit = fit;
 
-		ret = fit_open_configuration(data->os_fit, data->os_part);
-		if (ret) {
+		data->fit_config = fit_open_configuration(data->os_fit,
+							  data->os_part);
+		if (IS_ERR(data->fit_config)) {
 			printf("Cannot open FIT image configuration '%s'\n",
 			       data->os_part ? data->os_part : "default");
+			ret = PTR_ERR(data->fit_config);
 			goto err_out;
 		}
 
-		ret = fit_open_image(data->os_fit, "kernel", &data->fit_kernel,
-				     &data->fit_kernel_size);
+		ret = fit_open_image(data->os_fit, data->fit_config, "kernel",
+				     &data->fit_kernel, &data->fit_kernel_size);
 		if (ret)
-			goto err_out;;
+			goto err_out;
 	}
 
 	if (os_type == filetype_uimage) {
diff --git a/common/image-fit.c b/common/image-fit.c
index 8715689cfb..138696ab78 100644
--- a/common/image-fit.c
+++ b/common/image-fit.c
@@ -397,10 +397,11 @@ err_digest_free:
 	return ret;
 }
 
-int fit_has_image(struct fit_handle *handle, const char *name)
+int fit_has_image(struct fit_handle *handle, void *configuration,
+		  const char *name)
 {
 	const char *unit;
-	struct device_node *conf_node = handle->conf_node;
+	struct device_node *conf_node = configuration;
 
 	if (!conf_node)
 		return -EINVAL;
@@ -411,15 +412,16 @@ int fit_has_image(struct fit_handle *handle, const char *name)
 	return 1;
 }
 
-int fit_open_image(struct fit_handle *handle, const char *name,
-		   const void **outdata, unsigned long *outsize)
+int fit_open_image(struct fit_handle *handle, void *configuration,
+		   const char *name, const void **outdata,
+		   unsigned long *outsize)
 {
 	struct device_node *image = NULL, *hash;
 	const char *unit, *type = NULL, *desc= "(no description)";
 	const void *data;
 	int data_len;
 	int ret = 0;
-	struct device_node *conf_node = handle->conf_node;
+	struct device_node *conf_node = configuration;
 
 	if (!conf_node)
 		return -EINVAL;
@@ -546,7 +548,18 @@ default_unit:
 	return -ENOENT;
 }
 
-int fit_open_configuration(struct fit_handle *handle, const char *name)
+/**
+ * fit_open_configuration - open a FIT configuration
+ * @handle: The FIT image handle
+ * @name: The name of the configuration
+ *
+ * This opens a FIT configuration and eventually checks the signature
+ * depending on the verify mode the FIT image is opened with.
+ *
+ * Return: If successful a pointer to a valid configuration node,
+ *         otherwise a ERR_PTR()
+ */
+void *fit_open_configuration(struct fit_handle *handle, const char *name)
 {
 	struct device_node *conf_node = NULL;
 	const char *unit, *desc = "(no description)";
@@ -554,7 +567,7 @@ int fit_open_configuration(struct fit_handle *handle, const char *name)
 
 	conf_node = of_get_child_by_name(handle->root, "configurations");
 	if (!conf_node)
-		return -ENOENT;
+		return ERR_PTR(-ENOENT);
 
 	if (name) {
 		unit = name;
@@ -562,14 +575,14 @@ int fit_open_configuration(struct fit_handle *handle, const char *name)
 		ret = fit_find_compatible_unit(conf_node, &unit);
 		if (ret) {
 			pr_info("Couldn't get a valid configuration. Aborting.\n");
-			return ret;
+			return ERR_PTR(ret);
 		}
 	}
 
 	conf_node = of_get_child_by_name(conf_node, unit);
 	if (!conf_node) {
 		pr_err("configuration '%s' not found\n", unit);
-		return -ENOENT;
+		return ERR_PTR(-ENOENT);
 	}
 
 	of_property_read_string(conf_node, "description", &desc);
@@ -577,11 +590,9 @@ int fit_open_configuration(struct fit_handle *handle, const char *name)
 
 	ret = fit_config_verify_signature(handle, conf_node);
 	if (ret)
-		return ret;
+		return ERR_PTR(ret);
 
-	handle->conf_node = conf_node;
-
-	return 0;
+	return conf_node;
 }
 
 struct fit_handle *fit_open(const char *filename, bool verbose,