On Mon, May 22, 2017 at 12:17 PM, Simon Glass sjg@chromium.org wrote:
Most Chromebooks support chain-loading U-Boot but instructions are somewhat scattered. Add a README to hold this information within the U-Boot tree. Also add the standard developer keys to simplify the instructions, since they are small.
For now this only supports nyan-big.
Signed-off-by: Simon Glass sjg@chromium.org
doc/README.chromium | 222 +++++++++++++++++++++++++++ doc/chromium/devkeys/kernel.keyblock | Bin 0 -> 1208 bytes doc/chromium/devkeys/kernel_data_key.vbprivk | Bin 0 -> 1199 bytes 3 files changed, 222 insertions(+) create mode 100644 doc/README.chromium create mode 100644 doc/chromium/devkeys/kernel.keyblock create mode 100644 doc/chromium/devkeys/kernel_data_key.vbprivk
diff --git a/doc/README.chromium b/doc/README.chromium new file mode 100644 index 0000000000..1dd111c65d --- /dev/null +++ b/doc/README.chromium @@ -0,0 +1,222 @@ +Running U-Boot from coreboot on Chromebooks +===========================================
+U-Boot can be used as a secondary boot loader in a few situations such as from +UEFI and coreboot (see README.x86). Recent Chromebooks use coreboot even on +ARM platforms to start up the machine.
+This document aims to provide a guide to booting U-Boot on a Chromebook. It +is only a starting point, and there are many guides on the interwebs. But +placing this information in the U-Boot tree should make it easier to find for +those who use U-Boot habitually.
+Most of these platforms are supported by U-Boot natively, but it is risky to +replace the ROM unless you have a servo board and cable to restore it with.
+For all of these the standard U-Boot build instructions apply. For example on +ARM:
- sudo apt install gcc-arm-linux-gnueabi
- mkdir b
- make O=b/nyan_big CROSS_COMPILE=arm-linux-gnueabi- nyan-big_defconfig all
+You can obtain the vbutil_kernel utility here:
+Snow (Samsung ARM Chromebook) +-----------------------------
+See here:
+https://www.chromium.org/chromium-os/firmware-porting-guide/using-nv-u-boot-...
+Nyan-big +--------
+Compiled based on information here: +https://lists.denx.de/pipermail/u-boot/2015-March/209530.html +https://git.collabora.com/cgit/user/tomeu/u-boot.git/commit/?h=nyan-big +https://lists.denx.de/pipermail/u-boot/2017-May/289491.html +https://github.com/chromeos-nvidia-androidtv/gnu-linux-on-acer-chromebook-13...
+1. Patch U-Boot
+Open include/configs/tegra124-common.h
+Change:
+#define CONFIG_SYS_TEXT_BASE 0x80110000
+to:
+#define CONFIG_SYS_TEXT_BASE 0x81000100
One query on this one, is it possible to define or override that in configs/nyan-big_defconfig rather than in the include file. This would be useful from a distro PoV where we build numerous u-boot binaries from a single source tree.
Peter