From 17b05045bd82f04a8839666ec0fe43a5041d77c7 Mon Sep 17 00:00:00 2001 From: Brian Norris Date: Sat, 13 Jun 2020 20:12:18 -0700 Subject: ipq40xx: Support Chromium OS image-type creation See firmware-utils.git commits [1], which implemented the cros-vbutil verified-boot payload-packing tool, and extended ptgen for the CrOS kernel partition type. With these, it's now possible to package kernel + rootfs to make disk images that can boot a Chrome OS-based system (e.g., Chromebooks, or even a few AP models). Regarding PARTUUID= changes: Chromium bootloaders work well with a partition number offset (i.e., relative to the kernel partition), so we'll be using a slightly different root UUID line. NB: I've made this support specific to ip40xx for now, because I only plan to support an IPQ4019-based AP that uses a Chromium-based bootloader, but this image format can be used for essentially any Chromebook, as well as the Google OnHub, a prior Chromium-based AP using an IPQ8064 chipset. [1] ptgen: add Chromium OS kernel partition support https://git.openwrt.org/?p=project/firmware-utils.git;a=commit;h=6c95945b5de973026dc6f52eb088d0943efa96bb cros-vbutil: add Chrome OS vboot kernel-signing utility https://git.openwrt.org/?p=project/firmware-utils.git;a=commit;h=8e7274e02fdc6f2cb61b415d6e5b2e1c7e977aa1 Signed-off-by: Brian Norris --- target/linux/ipq40xx/image/chromium.mk | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) create mode 100644 target/linux/ipq40xx/image/chromium.mk (limited to 'target/linux/ipq40xx/image') diff --git a/target/linux/ipq40xx/image/chromium.mk b/target/linux/ipq40xx/image/chromium.mk new file mode 100644 index 0000000000..15d4c1a077 --- /dev/null +++ b/target/linux/ipq40xx/image/chromium.mk @@ -0,0 +1,22 @@ +define Build/cros-gpt + cp $@ $@.tmp 2>/dev/null || true + ptgen -o $@.tmp -g \ + -T cros_kernel -N kernel -p $(CONFIG_TARGET_KERNEL_PARTSIZE)m \ + -N rootfs -p $(CONFIG_TARGET_ROOTFS_PARTSIZE)m + cat $@.tmp >> $@ + rm $@.tmp +endef + +define Build/append-kernel-part + dd if=$(IMAGE_KERNEL) bs=$(CONFIG_TARGET_KERNEL_PARTSIZE)M conv=sync >> $@ +endef + +# NB: Chrome OS bootloaders replace the '%U' in command lines with the UUID of +# the kernel partition it chooses to boot from. This gives a flexible way to +# consistently build and sign kernels that always use the subsequent +# (PARTNROFF=1) partition as their rootfs. +define Build/cros-vboot + $(STAGING_DIR_HOST)/bin/cros-vbutil \ + -k $@ -c "root=PARTUUID=%U/PARTNROFF=1" -o $@.new + @mv $@.new $@ +endef -- cgit v1.2.3