dumpimage: fit: extract FIT images

The dumpimage is able to extract components contained in a FIT image:

  $ ./dumpimage -T flat_dt -i CONTAINER.ITB -p INDEX FILE

The CONTAINER.ITB is a regular FIT container file. The INDEX is the poisition
of the sub-image to be retrieved, and FILE is the file (path+name) to save the
extracted sub-image.

For example, given the following kernel.its to build a kernel.itb:

  /dts-v1/;
  / {
      ...
      images {
        kernel@1 {
          description = "Kernel 2.6.32-34";
          data = /incbin/("/boot/vmlinuz-2.6.32-34-generic");
          type = "kernel";
          arch = "ppc";
          os = "linux";
          compression = "gzip";
          load = <00000000>;
          entry = <00000000>;
          hash@1 {
            algo = "md5";
          };
        };
        ...
      };
      ...
    };

The dumpimage can extract the 'kernel@1' node through the following command:

  $ ./dumpimage -T flat_dt -i kernel.itb -p 0 kernel
  Extracted:
   Image 0 (kernel@1)
    Description:  Kernel 2.6.32-34
    Created:      Wed Oct 22 15:50:26 2014
    Type:         Kernel Image
    Compression:  gzip compressed
    Data Size:    4040128 Bytes = 3945.44 kB = 3.85 MB
    Architecture: PowerPC
    OS:           Linux
    Load Address: 0x00000000
    Entry Point:  0x00000000
    Hash algo:    md5
    Hash value:   22352ad39bdc03e2e50f9cc28c1c3652

Which results in the file 'kernel' being exactly the same as '/boot/vmlinuz-2.6.32-34-generic'.

Signed-off-by: Guilherme Maciel Ferreira <guilherme.maciel.ferreira@gmail.com>

1 files changed, 29 insertions, 1 deletions

diff --git a/common/image-fit.c b/common/image-fit.c
index 1589ee3..b47d110 100644
--- a/common/image-fit.c
+++ b/common/image-fit.c
@@ -112,6 +112,33 @@ static void fit_get_debug(const void *fit, int noffset,
 	      fdt_strerror(err));
 }
 
+/**
+ * fit_get_subimage_count - get component (sub-image) count
+ * @fit: pointer to the FIT format image header
+ * @images_noffset: offset of images node
+ *
+ * returns:
+ *     number of image components
+ */
+int fit_get_subimage_count(const void *fit, int images_noffset)
+{
+	int noffset;
+	int ndepth;
+	int count = 0;
+
+	/* Process its subnodes, print out component images details */
+	for (ndepth = 0, count = 0,
+		noffset = fdt_next_node(fit, images_noffset, &ndepth);
+	     (noffset >= 0) && (ndepth > 0);
+	     noffset = fdt_next_node(fit, noffset, &ndepth)) {
+		if (ndepth == 1) {
+			count++;
+		}
+	}
+
+	return count;
+}
+
 #if !defined(CONFIG_SPL_BUILD) || defined(CONFIG_FIT_SPL_PRINT)
 /**
  * fit_print_contents - prints out the contents of the FIT format image
@@ -423,7 +450,8 @@ void fit_image_print(const void *fit, int image_noffset, const char *p)
 		}
 	}
 }
-#endif
+
+#endif /* !defined(CONFIG_SPL_BUILD) || defined(CONFIG_FIT_SPL_PRINT) */
 
 /**
  * fit_get_desc - get node description property