From: Bryan O'Donoghue Date: Mon, 23 Jul 2018 13:27:59 +0000 (+0100) Subject: docs: warp7: Add description for the i.MX7 WaRP7 platform X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=b182a5d989db02ad44ab5ea783b919d177c2bb41;p=project%2Fbcm63xx%2Fatf.git docs: warp7: Add description for the i.MX7 WaRP7 platform This patch describes the boot-flow and building of the WaRP7 TF-A port. What it describes is booting and unsigned TF-A. A very brief section has been added on signing BL2 which is in no-way comprehensive. For a comprehensive description of the signing process try the Boundary Devices blog on the matter. https://boundarydevices.com/high-assurance-boot-hab-dummies/ Signed-off-by: Bryan O'Donoghue --- diff --git a/docs/plat/warp7.rst b/docs/plat/warp7.rst new file mode 100644 index 00000000..51c2609b --- /dev/null +++ b/docs/plat/warp7.rst @@ -0,0 +1,156 @@ +Trusted Firmware-A for i.MX7 WaRP7 +================================== + +The Trusted Firmware-A port for the i.MX7Solo WaRP7 implements BL2 at EL3. +The i.MX7S contains a BootROM with a High Assurance Boot (HAB) functionality. +This functionality provides a mechanism for establishing a root-of-trust from +the reset vector to the command-line in user-space. + +Boot Flow +========= + +BootROM --> TF-A BL2 --> BL32(OP-TEE) --> BL33(U-Boot) --> Linux + +In the WaRP7 port we encapsulate OP-TEE, DTB and U-Boot into a FIP. This FIP is +expected and required + +# Build Instructions + +We need to use a file generated by u-boot in order to generate a .imx image the +BootROM will boot. It is therefore _required_ to build u-boot before TF-A and +furthermore it is _recommended_ to use the mkimage in the u-boot/tools directory +to generate the TF-A .imx image. + +## U-Boot: + +https://git.linaro.org/landing-teams/working/mbl/u-boot.git + +.. code:: shell + + git checkout -b rms-atf-optee-uboot linaro-mbl/rms-atf-optee-uboot + make warp7_bl33_defconfig; + make u-boot.imx arch=ARM CROSS_COMPILE=arm-linux-gnueabihf- + +## TF-A: + +https://github.com/ARM-software/arm-trusted-firmware.git + +.. code:: shell + + make CROSS_COMPILE=arm-linux-gnueabihf- PLAT=warp7 ARCH=aarch32 ARM_ARCH_MAJOR=7 ARM_CORTEX_A7=yes AARCH32_SP=optee all + /path/to/u-boot/tools/mkimage -n /path/to/u-boot/u-boot.cfgout -T imximage -e 0x9df00000 -d ./build/warp7/debug/bl2.bin ./build/warp7/debug/bl2.bin.imx + +## OP-TEE: + +https://github.com/OP-TEE/optee_os.git + +.. code:: shell + + make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- PLATFORM=imx PLATFORM_FLAVOR=mx7swarp7 ARCH=arm CFG_PAGEABLE_ADDR=0 CFG_DT_ADDR=0x83000000 CFG_NS_ENTRY_ADDR=0x87800000 + + +## FIP: + +.. code:: shell + + mkdir fiptool_images + cp /path/to/uboot/u-boot.bin fiptool_images + cp /path/to/optee/out/arm-plat-imx/core/tee-header_v2.bin fiptool_images + cp /path/to/optee/out/arm-plat-imx/core/tee-pager_v2.bin fiptool_images + cp /path/to/optee/out/arm-plat-imx/core/tee-pageable_v2.bin fiptool_images + cp /path/to/linux/arch/boot/dts/imx7s-warp.dtb fiptool_images + tools/fiptool/fiptool create --tos-fw fiptool_images/tee-header_v2.bin --tos-fw-extra1 fiptool_images/tee-pager_v2.bin --tos-fw-extra2 fiptool_images/tee-pageable_v2.bin --nt-fw fiptool_images/u-boot.bin --hw-config fiptool_images/imx7s-warp.dtb warp7.fip + + +# Deploy Images + + +First place the WaRP7 into UMS mode in u-boot this should produce an entry in +/dev like /dev/disk/by-id/usb-Linux_UMS_disk_0_WaRP7-0xf42400d3000001d4-0\:0 + +.. code:: shell + + => ums 0 mmc 0 + +Next flash bl2.imx and warp7.fip + +bl2.imx is flashed @ 1024 bytes +warp7.fip is flash @ 1048576 bytes + +.. code:: shell + + sudo dd if=bl2.bin.imx of=/dev/disk/by-id/usb-Linux_UMS_disk_0_WaRP7-0xf42400d3000001d4-0\:0 bs=512 seek=2 conv=notrunc + # Offset is 1MB 1048576 => 1048576 / 512 = 2048 + sudo dd if=./warp7.fip of=/dev/disk/by-id/usb-Linux_UMS_disk_0_WaRP7-0xf42400d3000001d4-0\:0 bs=512 seek=2048 conv=notrunc + +Remember to umount the USB device pefore proceeding + +.. code:: shell + + sudo umount /dev/disk/by-id/usb-Linux_UMS_disk_0_WaRP7-0xf42400d3000001d4-0\:0* + + +# Signing BL2 + +A further step is to sign BL2. + +The image_sign.sh and bl2_sign.csf files alluded to blow are available here. + +https://github.com/bryanodonoghue/atf-code-signing + +It is suggested you use this script plus the example CSF file in order to avoid +hard-coding data into your CSF files. + +Download both "image_sign.sh" and "bl2_sign.csf" to your +arm-trusted-firmware top-level directory. + +.. code:: shell + + #!/bin/bash + SIGN=image_sign.sh + TEMP=`pwd`/temp + BL2_CSF=bl2_sign.csf + BL2_IMX=bl2.bin.imx + CST_PATH=/path/to/cst-2.3.2 + CST_BIN=${CST_PATH}/linux64/cst + + #Remove temp + rm -rf ${TEMP} + mkdir ${TEMP} + + # Generate IMX header + /path/to/u-boot/tools/mkimage -n u-boot.cfgout.warp7 -T imximage -e 0x9df00000 -d ./build/warp7/debug/bl2.bin ./build/warp7/debug/bl2.bin.imx > ${TEMP}/${BL2_IMX}.log + + # Copy required items to $TEMP + cp build/warp7/debug/bl2.bin.imx ${TEMP} + cp ${CST_PATH}/keys/* ${TEMP} + cp ${CST_PATH}/crts/* ${TEMP} + cp ${BL2_CSF} ${TEMP} + + # Generate signed BL2 image + ./${SIGN} image_sign_mbl_binary ${TEMP} ${BL2_CSF} ${BL2_IMX} ${CST_BIN} + + # Copy signed BL2 to top-level directory + cp ${TEMP}/${BL2_IMX}-signed . + cp ${BL2_RECOVER_CSF} ${TEMP} + + +The resulting bl2.bin.imx-signed can replace bl2.bin.imx in the Deploy +Images section above, once done. + +Suggested flow for verifying. + +1. Followed all previous steps above and verify a non-secure ATF boot +2. Down the NXP Code Singing Tool +3. Generate keys +4. Program the fuses on your board +5. Replace bl2.bin.imx with bl2.bin.imx-signed +6. Verify inside u-boot that "hab_status" shows no events +7. Subsequently close your board. + +If you have HAB events @ step 6 - do not lock your board. + +To get a good over-view of generating keys and programming the fuses on the +board read "High Assurance Boot for Dummies" by Boundary Devices. + +https://boundarydevices.com/high-assurance-boot-hab-dummies/