[ath79] DTB update mechanism

juppin · January 16, 2020, 3:50pm

Seems so...

openwrt/openwrt/blob/openwrt-19.07/target/linux/ath79/image/common-tp-link.mk#L66


      
            IMAGES += factory.bin
            IMAGE/sysupgrade.bin := append-rootfs | mktplinkfw sysupgrade | append-metadata
            IMAGE/factory.bin := append-rootfs | mktplinkfw factory
          endef
          
          define Device/tplink-nolzma
            $(Device/tplink)
            LOADER_FLASH_OFFS := 0x22000
            COMPILE := loader-$(1).gz
            COMPILE/loader-$(1).gz := loader-okli-compile
            KERNEL := kernel-bin | append-dtb | lzma | uImage lzma -M 0x4f4b4c49 | loader-okli $(1) 7680
            KERNEL_INITRAMFS := kernel-bin | append-dtb | gzip | tplink-v1-header
          endef
          
          define Device/tplink-4m
            $(Device/tplink-nolzma)
            TPLINK_FLASHLAYOUT := 4M
            IMAGE_SIZE := 3904k
            DEFAULT := n
          endef

kernel-bin = vmlinux
append-dtb = image-ar7241_tplink_tl-mr3220-v1.dtb
lzma = ./staging_dir/host/bin/lzma e -lc1 -lp2 -pb2
uImage = ./staging_dir/host/bin/mkimage -A mips -O linux -T kernel -C lzma -a 0x80060000 -e 0x80060000 -n "OpenWRT Linux" -M 0x4f4b4c49 -d
loader-okli = loader-tplink_tl-mr3220-v1.gz

So try something like:

$ cd path/to/image-builder-root/
$ mv build_dir/target-mips_24kc_musl/linux-ath79_tiny/tplink_tl-mr3220-v1-kernel.bin build_dir/target-mips_24kc_musl/linux-ath79_tiny/tplink_tl-mr3220-v1-kernel.bin.org
$ cat build_dir/target-mips_24kc_musl/linux-ath79_tiny/vmlinux build_dir/target-mips_24kc_musl/linux-ath79_tiny/image-ar7241_tplink_tl-mr3220-v1.dtb > build_dir/target-mips_24kc_musl/linux-ath79_tiny/vmlinux-with-dtb
$ ./staging_dir/host/bin/lzma e -lc1 -lp2 -pb2 build_dir/target-mips_24kc_musl/linux-ath79_tiny/vmlinux-with-dtb build_dir/target-mips_24kc_musl/linux-ath79_tiny/vmlinux-with-dtb.lzma
$ dd if=build_dir/target-mips_24kc_musl/linux-ath79_tiny/loader-tplink_tl-mr3220-v1.gz bs=7680 conv=sync of=build_dir/target-mips_24kc_musl/linux-ath79_tiny/loader-tplink_tl-mr3220-v1.gz.padded
$ ./staging_dir/host/bin/mkimage -A mips -O linux -T kernel -C lzma -a 0x80060000 -e 0x80060000 -n "OpenWRT Linux" -M 0x4f4b4c49 -d build_dir/target-mips_24kc_musl/linux-ath79_tiny/vmlinux-with-dtb.lzma build_dir/target-mips_24kc_musl/linux-ath79_tiny/vmlinux-with-dtb.uImage
$ cat build_dir/target-mips_24kc_musl/linux-ath79_tiny/loader-tplink_tl-mr3220-v1.gz.padded build_dir/target-mips_24kc_musl/linux-ath79_tiny/vmlinux-with-dtb.uImage > build_dir/target-mips_24kc_musl/linux-ath79_tiny/tplink_tl-mr3220-v1-kernel.bin

Don´t forget to fix dtb before this!

It does produce the same output with binwalk:

$ binwalk build_dir/target-mips_24kc_musl/linux-ath79_tiny/tplink_tl-mr3220-v1-kernel.bin.org

DECIMAL       HEXADECIMAL     DESCRIPTION
--------------------------------------------------------------------------------
0             0x0             gzip compressed data, maximum compression, from Unix, last modified: 1970-01-01 00:00:00 (null date)
7744          0x1E40          LZMA compressed data, properties: 0x6D, dictionary size: 8388608 bytes, uncompressed size: 4454620 bytes

$ binwalk build_dir/target-mips_24kc_musl/linux-ath79_tiny/tplink_tl-mr3220-v1-kernel.bin

DECIMAL       HEXADECIMAL     DESCRIPTION
--------------------------------------------------------------------------------
0             0x0             gzip compressed data, maximum compression, from Unix, last modified: 1970-01-01 00:00:00 (null date)
7744          0x1E40          LZMA compressed data, properties: 0x6D, dictionary size: 8388608 bytes, uncompressed size: 4454620 bytes

EDIT: Updated step with mkimage