Hi Hauke,
On Mon, 23 Jan 2023 at 15:45, Hauke Mehrtens hauke@hauke-m.de wrote:
On 1/23/23 19:49, Simon Glass wrote:
Hi,
On Sun, 22 Jan 2023 at 07:20, Hauke Mehrtens hauke@hauke-m.de wrote:
Extend mkimage with a new optional option -M to specify a special U-Boot image magic number. OpenWrt ships images for about 30 different boards with vendor boot loaders which are expecting the mkimage format, but with a different image magic.
OpenWrt includes this patch for mkimage more than 10 years. It was added by Gabor Juhos in this commit: https://git.openwrt.org/?p=openwrt/openwrt.git;a=commitdiff;h=f3d2056b81b7a9...
Cc: Gabor Juhos j4g8y7@gmail.com Signed-off-by: Hauke Mehrtens hauke@hauke-m.de
tools/default_image.c | 4 ++-- tools/imagetool.h | 1 + tools/mkimage.c | 14 ++++++++++++-- 3 files changed, 15 insertions(+), 4 deletions(-)
Strange...what is the different magic for?
I do not know really know why some vendors do this. With Openwrt we create images which user can install on their devices. We normally do not change the vendor bootloader and create an image which is compatible with the vendor boot loader.
I assume the vendors want to prevent users from installing "unsupported" images, but still want to use something close to the U-Boot image. With a different magic their boot loader (often vendor modified U-Boot) can prevent the user from installing "wrong" images.
I saw this on many devices sold by NetGear for example these devices: NETGEAR WNDR4300 NETGEAR WNDR4500 NETGEAR WNR1000 NETGEAR WNR612 v2
I have also seen it from other vendors, probably some ODM or OEM does this.
OK, but I think it would be better to use a FIT, thus allowing the vendor to add more info into the file.
Are the vendor bootloaders upstreamed?
Anyway, I don't see a big problem with doing this. Can you please update the mkimage man page? Do we need to update dumpimage also?
Regards, Simon