xload: get barebox size from barebox_arm_head

Add functions to read the barebox_arm_head, check barebox magicword
and read out the barebox image size.
Create a inital partion of 1Mb to access the barebox image on nand.

Signed-off-by: Jan Weitzel <j.weitzel@phytec.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

1 files changed, 53 insertions, 4 deletions

diff --git a/arch/arm/mach-omap/xload.c b/arch/arm/mach-omap/xload.c
index 13024abac7..0afeea9ce5 100644
--- a/arch/arm/mach-omap/xload.c
+++ b/arch/arm/mach-omap/xload.c
@@ -7,16 +7,65 @@
 #include <fcntl.h>
 #include <mach/xload.h>
 #include <sizes.h>
+#include <filetype.h>
 
-void *omap_xload_boot_nand(int offset, int size)
+void *read_image_head(const char *name)
 {
+	void *header = xmalloc(ARM_HEAD_SIZE);
+	struct cdev *cdev;
 	int ret;
-	void *to = xmalloc(size);
+
+	cdev = cdev_open(name, O_RDONLY);
+	if (!cdev) {
+		printf("failed to open partition\n");
+		return NULL;
+	}
+
+	ret = cdev_read(cdev, header, ARM_HEAD_SIZE, 0, 0);
+	cdev_close(cdev);
+
+	if (ret != ARM_HEAD_SIZE) {
+		printf("failed to read from partition\n");
+		return NULL;
+	}
+
+	return header;
+}
+
+unsigned int get_image_size(void *head)
+{
+	unsigned int ret = 0;
+	unsigned int *psize = head + ARM_HEAD_SIZE_OFFSET;
+
+	if (is_barebox_arm_head(head))
+		ret = *psize;
+	debug("Detected barebox image size %u\n", ret);
+
+	return ret;
+}
+
+void *omap_xload_boot_nand(int offset)
+{
+	int ret;
+	int size;
+	void *to, *header;
 	struct cdev *cdev;
 
-	devfs_add_partition("nand0", offset, size, DEVFS_PARTITION_FIXED, "x");
+	devfs_add_partition("nand0", offset, SZ_1M, DEVFS_PARTITION_FIXED, "x");
 	dev_add_bb_dev("x", "bbx");
 
+	header = read_image_head("bbx");
+	if (header == NULL)
+		return NULL;
+
+	size = get_image_size(header);
+	if (!size) {
+		printf("failed to get image size\n");
+		return NULL;
+	}
+
+	to = xmalloc(size);
+
 	cdev = cdev_open("bbx", O_RDONLY);
 	if (!cdev) {
 		printf("failed to open nand\n");
@@ -80,7 +129,7 @@ int run_shell(void)
 		printf("unknown boot source. Fall back to nand\n");
 	case OMAP_BOOTSRC_NAND:
 		printf("booting from NAND\n");
-		func = omap_xload_boot_nand(SZ_128K, SZ_256K);
+		func = omap_xload_boot_nand(SZ_128K);
 		break;
 	}