mkbootimg: Add --dt parameter to specify DT image

New optional --dt parameter to specify a kernel device
tree image.

Change-Id: I7e2c48c25c04165642eedadc3dc16a082dd99eb0

Author: David Ng

mkbootimg/bootimg.h

@@ -40,8 +40,8 @@ struct boot_img_hdr
 
     unsigned tags_addr;    /* physical addr for kernel tags */
     unsigned page_size;    /* flash page size we assume */
-    unsigned unused[2];    /* future expansion: should be 0 */
-
+    unsigned dt_size;      /* device tree in bytes */
+    unsigned unused;       /* future expansion: should be 0 */
     unsigned char name[BOOT_NAME_SIZE]; /* asciiz product name */
 
     unsigned char cmdline[BOOT_ARGS_SIZE];
@@ -59,10 +59,13 @@ struct boot_img_hdr
 ** +-----------------+
 ** | second stage    | o pages
 ** +-----------------+
+** | device tree     | p pages
+** +-----------------+
 **
 ** n = (kernel_size + page_size - 1) / page_size
 ** m = (ramdisk_size + page_size - 1) / page_size
 ** o = (second_size + page_size - 1) / page_size
+** p = (dt_size + page_size - 1) / page_size
 **
 ** 0. all entities are page_size aligned in flash
 ** 1. kernel and ramdisk are required (size != 0)

mkbootimg/mkbootimg.c

@@ -66,6 +66,7 @@ int usage(void)
             "       [ --base <address> ]\n"
             "       [ --pagesize <pagesize> ]\n"
             "       [ --ramdisk_offset <address> ]\n"
+            "       [ --dt <filename> ]\n"
             "       -o|--output <filename>\n"
             );
     return 1;
@@ -106,6 +107,8 @@ int main(int argc, char **argv)
     char *cmdline = "";
     char *bootimg = 0;
     char *board = "";
+    char *dt_fn = 0;
+    void *dt_data = 0;
     unsigned pagesize = 2048;
     int fd;
     SHA_CTX ctx;
@@ -157,6 +160,8 @@ int main(int argc, char **argv)
                 fprintf(stderr,"error: unsupported page size %d\n", pagesize);
                 return -1;
             }
+        } else if(!strcmp(arg, "--dt")) {
+            dt_fn = val;
         } else {
             return usage();
         }
@@ -223,6 +228,14 @@ int main(int argc, char **argv)
         }
     }
 
+    if(dt_fn) {
+        dt_data = load_file(dt_fn, &hdr.dt_size);
+        if (dt_data == 0) {
+            fprintf(stderr,"error: could not load device tree image '%s'\n", dt_fn);
+            return 1;
+        }
+    }
+
     /* put a hash of the contents in the header so boot images can be
      * differentiated based on their first 2k.
      */
@@ -233,6 +246,10 @@ int main(int argc, char **argv)
     SHA_update(&ctx, &hdr.ramdisk_size, sizeof(hdr.ramdisk_size));
     SHA_update(&ctx, second_data, hdr.second_size);
     SHA_update(&ctx, &hdr.second_size, sizeof(hdr.second_size));
+    if(dt_data) {
+        SHA_update(&ctx, dt_data, hdr.dt_size);
+        SHA_update(&ctx, &hdr.dt_size, sizeof(hdr.dt_size));
+    }
     sha = SHA_final(&ctx);
     memcpy(hdr.id, sha,
            SHA_DIGEST_SIZE > sizeof(hdr.id) ? sizeof(hdr.id) : SHA_DIGEST_SIZE);
@@ -257,6 +274,10 @@ int main(int argc, char **argv)
         if(write_padding(fd, pagesize, hdr.ramdisk_size)) goto fail;
     }
 
+    if(dt_data) {
+        if(write(fd, dt_data, hdr.dt_size) != hdr.dt_size) goto fail;
+        if(write_padding(fd, pagesize, hdr.dt_size)) goto fail;
+    }
     return 0;
 
 fail: