[U-Boot] [PATCH 7/7] nhk8815: documented how to replace u-boot on flash

[Alessandro Rubini]

From: Alessandro Rubini <rubini at unipv.it>


Signed-off-by: Alessandro Rubini <rubini at unipv.it>
Acked-by: Andrea Gallo <andrea.gallo at stericsson.com>
---
 doc/README.nhk8815 |   20 ++++++++++++++++++++
 1 files changed, 20 insertions(+), 0 deletions(-)

diff --git a/doc/README.nhk8815 b/doc/README.nhk8815
index 9008e39..365d7e1 100644
--- a/doc/README.nhk8815
+++ b/doc/README.nhk8815
@@ -26,6 +26,26 @@ where it was loaded from, the configurations differ in where the filesystem
 is looked for by default.
 
 
+** How to replace U-Boot with your own
+
+Due to the "secure" boot described above, The U-Boot binary isn't
+expected to live at the beginning of the NAND flash but rather at
+0x80800 (offset 2kB within /dev/mtd).
+
+To replace it with your own binary you should either use the serial
+flasher the vendor distributes (there is a version running on
+GNU/Linux too) or with the following commands from U-Boot.
+These commands read 256kB from the are that will be /dev/mtd2 and
+overwrite U-Boot at offset 2kB:
+
+    nand read  100000 80000 40000
+    bootp      100800 u-boot-nhl8815.bin
+    nand erase  80000 40000
+    nand write 100000 80000 40000
+
+
+** Further documentation
+
 On www.st.com/nomadik and on www.stnwireless.com there are documents,
 summary data and white papers on Nomadik. The full datasheet for
 STn8815 is not currently available on line but under specific request
-- 
1.6.0.2