tools/firmware-utils: document reserved fields in mkchkimg

[openwrt/openwrt.git] / tools / firmware-utils / src / mkchkimg.c

diff --git a/tools/firmware-utils/src/mkchkimg.c b/tools/firmware-utils/src/mkchkimg.c
index e152f7d4685b6b2a53133ea8b94ad8dd37657ac4..0fe01f07079f7af00a560dc8e2b68fdc41222dd0 100644 (file)
--- a/tools/firmware-utils/src/mkchkimg.c
+++ b/tools/firmware-utils/src/mkchkimg.c
@@ -31,6 +31,20 @@
 
 #define MAX_BOARD_ID_LEN (64)
 
+/*
+ * Note on the reserved field of the chk_header:
+ * OFW naming scheme is typically: DEVICENAME-VA.B.C.D_E.F.G.chk, with A-G
+ * between 0 and 255. For instance: EX3700_EX3800-V1.0.0.58_1.0.38.chk
+ * The reserved field works like this:
+ * reserved[0]: region code. 1 for WW (WorldWide) and 2 for NA (North America)
+ * reserved[1]: A
+ * reserved[2]: B
+ * reserved[3]: C
+ * reserved[4]: D
+ * reserved[5]: E
+ * reserved[6]: F
+ * reserved[7]: G
+ */
 struct chk_header {
        uint32_t magic;
        uint32_t header_len;
@@ -248,10 +262,10 @@ main (int argc, char * argv[])
        hdr->reserved[1] = 1;           /* Major */
        hdr->reserved[2] = 1;           /* Minor */
        hdr->reserved[3] = 99;          /* Build */
-       hdr->reserved[4] = 0;           /* Unknown t1 ? was 1 */
-       hdr->reserved[5] = 0;           /* Unknonw t2 ? was 0 */
-       hdr->reserved[6] = 0;           /* Unknonw t3 ? was 1 */
-       hdr->reserved[7] = 0;           /* Unused ? */
+       hdr->reserved[4] = 0;
+       hdr->reserved[5] = 0;
+       hdr->reserved[6] = 0;
+       hdr->reserved[7] = 0;
        message ("       Board Id: %s", board_id);
        message ("         Region: %s", region == 1 ? "World Wide (WW)" 
                        : (region == 2 ? "North America (NA)" : "Unknown"));