image: Tidy up genimg_get_kernel_addr_fit()

This function does not modify its first argument, so mark it const. Also
move the comments to the header file and expand them to provide more
useful information.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>

1 files changed, 26 insertions, 3 deletions

diff --git a/include/image.h b/include/image.h
index 2e3cf839ee3..798c5f9c16e 100644
--- a/include/image.h
+++ b/include/image.h
@@ -612,9 +612,32 @@ int boot_get_setup(struct bootm_headers *images, uint8_t arch, ulong *setup_star
 #define IMAGE_FORMAT_FIT	0x02	/* new, libfdt based format */
 #define IMAGE_FORMAT_ANDROID	0x03	/* Android boot image */
 
-ulong genimg_get_kernel_addr_fit(char * const img_addr,
-			         const char **fit_uname_config,
-			         const char **fit_uname_kernel);
+/**
+ * genimg_get_kernel_addr_fit() - Parse FIT specifier
+ *
+ * Get the real kernel start address from a string which is normally the first
+ * argv of bootm/bootz
+ *
+ * These cases are dealt with, based on the value of @img_addr:
+ *    NULL: Returns image_load_addr, does not set last two args
+ *    "<addr>": Returns address
+ *
+ * For FIT:
+ *    "[<addr>]#<conf>": Returns address (or image_load_addr),
+ *	sets fit_uname_config to config name
+ *    "[<addr>]:<subimage>": Returns address (or image_load_addr) and sets
+ *	fit_uname_kernel to the subimage name
+ *
+ * @img_addr: a string might contain real image address (or NULL)
+ * @fit_uname_config: Returns configuration unit name
+ * @fit_uname_kernel: Returns subimage name
+ *
+ * Returns: kernel start address
+ */
+ulong genimg_get_kernel_addr_fit(const char *const img_addr,
+				 const char **fit_uname_config,
+				 const char **fit_uname_kernel);
+
 ulong genimg_get_kernel_addr(char * const img_addr);
 int genimg_get_format(const void *img_addr);
 int genimg_has_config(struct bootm_headers *images);