SPL: FIT: refactor FDT loading
Currently the SPL FIT loader uses the spl_fit_select_fdt() function to
find the offset to the right DTB within the FIT image.
For this it iterates over all subnodes of the /configuration node in
the FIT tree and compares all "description" strings therein using a
board specific matching function.
If that finds a match, it uses the string in the "fdt" property of that
subnode to locate the matching subnode in the /images node, which points
to the DTB data.
Now this works very well, but is quite specific to cover this particular
use case. To open up the door for a more generic usage, let's split this
function into:
1) a function that just returns the node offset for the matching
configuration node (spl_fit_find_config_node())
2) a function that returns the image data any given property in a given
configuration node points to, additionally using a given index into
a possbile list of strings (spl_fit_select_index())
This allows us to replace the specific function above by asking for the
image the _first string of the "fdt" property_ in the matching
configuration subnode points to.
This patch introduces no functional changes, it just refactors the code
to allow reusing it later.
(diff is overly clever here and produces a hard-to-read patch, so I
recommend to throw a look at the result instead).
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Lokesh Vutla <lokeshvuta@ti.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
Tested-by: Kever Yang <kever.yang@rock-chips.com>
Tested-by: Jagan Teki <jagan@openedev.com>
diff --git a/common/spl/spl_fit.c b/common/spl/spl_fit.c
index aae556f..67372ca 100644
--- a/common/spl/spl_fit.c
+++ b/common/spl/spl_fit.c
@@ -22,13 +22,16 @@
return fdt32_to_cpu(*cell);
}
-static int spl_fit_select_fdt(const void *fdt, int images, int *fdt_offsetp)
+/*
+ * Iterate over all /configurations subnodes and call a platform specific
+ * function to find the matching configuration.
+ * Returns the node offset or a negative error number.
+ */
+static int spl_fit_find_config_node(const void *fdt)
{
- const char *name, *fdt_name;
- int conf, node, fdt_node;
- int len;
+ const char *name;
+ int conf, node, len;
- *fdt_offsetp = 0;
conf = fdt_path_offset(fdt, FIT_CONFS_PATH);
if (conf < 0) {
debug("%s: Cannot find /configurations node: %d\n", __func__,
@@ -50,41 +53,63 @@
continue;
debug("Selecting config '%s'", name);
- fdt_name = fdt_getprop(fdt, node, FIT_FDT_PROP, &len);
- if (!fdt_name) {
- debug("%s: Cannot find fdt name property: %d\n",
- __func__, len);
- return -EINVAL;
- }
- debug(", fdt '%s'\n", fdt_name);
- fdt_node = fdt_subnode_offset(fdt, images, fdt_name);
- if (fdt_node < 0) {
- debug("%s: Cannot find fdt node '%s': %d\n",
- __func__, fdt_name, fdt_node);
- return -EINVAL;
- }
-
- *fdt_offsetp = fdt_getprop_u32(fdt, fdt_node, "data-offset");
- len = fdt_getprop_u32(fdt, fdt_node, "data-size");
- debug("FIT: Selected '%s'\n", name);
-
- return len;
+ return node;
}
-#ifdef CONFIG_SPL_LIBCOMMON_SUPPORT
- printf("No matching DT out of these options:\n");
- for (node = fdt_first_subnode(fdt, conf);
- node >= 0;
- node = fdt_next_subnode(fdt, node)) {
- name = fdt_getprop(fdt, node, "description", &len);
- printf(" %s\n", name);
- }
-#endif
-
return -ENOENT;
}
+static int spl_fit_select_index(const void *fit, int images, int *offsetp,
+ const char *type, int index)
+{
+ const char *name, *str;
+ int node, conf_node;
+ int len, i;
+
+ *offsetp = 0;
+ conf_node = spl_fit_find_config_node(fit);
+ if (conf_node < 0) {
+#ifdef CONFIG_SPL_LIBCOMMON_SUPPORT
+ printf("No matching DT out of these options:\n");
+ for (node = fdt_first_subnode(fit, conf_node);
+ node >= 0;
+ node = fdt_next_subnode(fit, node)) {
+ name = fdt_getprop(fit, node, "description", &len);
+ printf(" %s\n", name);
+ }
+#endif
+ return conf_node;
+ }
+
+ name = fdt_getprop(fit, conf_node, type, &len);
+ if (!name) {
+ debug("cannot find property '%s': %d\n", type, len);
+ return -EINVAL;
+ }
+
+ str = name;
+ for (i = 0; i < index; i++) {
+ str = strchr(str, '\0') + 1;
+ if (!str || (str - name >= len)) {
+ debug("no string for index %d\n", index);
+ return -E2BIG;
+ }
+ }
+
+ debug("%s: '%s'\n", type, str);
+ node = fdt_subnode_offset(fit, images, str);
+ if (node < 0) {
+ debug("cannot find image node '%s': %d\n", str, node);
+ return -EINVAL;
+ }
+
+ *offsetp = fdt_getprop_u32(fit, node, "data-offset");
+ len = fdt_getprop_u32(fit, node, "data-size");
+
+ return len;
+}
+
static int get_aligned_image_offset(struct spl_load_info *info, int offset)
{
/*
@@ -218,7 +243,8 @@
memcpy(dst, src, data_size);
/* Figure out which device tree the board wants to use */
- fdt_len = spl_fit_select_fdt(fit, images, &fdt_offset);
+ fdt_len = spl_fit_select_index(fit, images, &fdt_offset,
+ FIT_FDT_PROP, 0);
if (fdt_len < 0)
return fdt_len;