rockchip: mkimage: clarify header0 initialisation
This change set adds documentation to the header0 initialisation and
improves readability for the calculations of various offsets/lengths.
As the U-Boot SPL stage doesn't use any payload beyond what is covered
by init_size, we no longer add RK_MAX_BOOT_SIZE to init_boot_size.
Signed-off-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
Acked-by: Simon Glass <sjg@chromium.org>
diff --git a/tools/rkcommon.c b/tools/rkcommon.c
index 1880fef..f826001 100644
--- a/tools/rkcommon.c
+++ b/tools/rkcommon.c
@@ -13,6 +13,8 @@
#include "mkimage.h"
#include "rkcommon.h"
+#define DIV_ROUND_UP(n, d) (((n) + (d) - 1) / (d))
+
enum {
RK_SIGNATURE = 0x0ff0aa55,
};
@@ -160,9 +162,21 @@
hdr->disable_rc4 = !rkcommon_need_rc4_spl(params);
hdr->init_offset = RK_INIT_OFFSET;
- hdr->init_size = (file_size + RK_BLK_SIZE - 1) / RK_BLK_SIZE;
- hdr->init_size = (hdr->init_size + 3) & ~3;
- hdr->init_boot_size = hdr->init_size + RK_MAX_BOOT_SIZE / RK_BLK_SIZE;
+ hdr->init_size = DIV_ROUND_UP(file_size, RK_BLK_SIZE);
+ /*
+ * The init_size has to be a multiple of 4 blocks (i.e. of 2K)
+ * or the BootROM will not boot the image.
+ *
+ * Note: To verify that this is not a legacy constraint, we
+ * rechecked this against the RK3399 BootROM.
+ */
+ hdr->init_size = ROUND(hdr->init_size, 4);
+ /*
+ * The images we create do not contain the stage following the SPL as
+ * part of the SPL image, so the init_boot_size (which might have been
+ * read by Rockchip's miniloder) should be the same as the init_size.
+ */
+ hdr->init_boot_size = hdr->init_size;
rc4_encode(buf, RK_BLK_SIZE, rc4_key);
}