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Diffstat (limited to 'docs')
| -rw-r--r-- | docs/user-guide.rst | 107 |
1 files changed, 79 insertions, 28 deletions
diff --git a/docs/user-guide.rst b/docs/user-guide.rst index 4a8c3a156..280831448 100644 --- a/docs/user-guide.rst +++ b/docs/user-guide.rst @@ -1484,41 +1484,92 @@ without a BL33 and prepare to jump to a BL33 image loaded at address make PRELOADED_BL33_BASE=0x80000000 PLAT=fvp all fip -Boot of a preloaded bootwrapped kernel image on Base FVP -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +Boot of a preloaded kernel image on Base FVP +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -The following example uses the AArch64 boot wrapper. This simplifies normal -world booting while also making use of TF-A features. It can be obtained from -its repository with: +The following example uses a simplified boot flow by directly jumping from the +TF-A to the Linux kernel, which will use a ramdisk as filesystem. This can be +useful if both the kernel and the device tree blob (DTB) are already present in +memory (like in FVP). -:: +For example, if the kernel is loaded at ``0x80080000`` and the DTB is loaded at +address ``0x82000000``, the firmware can be built like this: - git clone git://git.kernel.org/pub/scm/linux/kernel/git/mark/boot-wrapper-aarch64.git +:: -After compiling it, an ELF file is generated. It can be loaded with the -following command: + CROSS_COMPILE=aarch64-linux-gnu- \ + make PLAT=fvp DEBUG=1 \ + RESET_TO_BL31=1 \ + ARM_LINUX_KERNEL_AS_BL33=1 \ + PRELOADED_BL33_BASE=0x80080000 \ + ARM_PRELOADED_DTB_BASE=0x82000000 \ + all fip + +Now, it is needed to modify the DTB so that the kernel knows the address of the +ramdisk. The following script generates a patched DTB from the provided one, +assuming that the ramdisk is loaded at address ``0x84000000``. Note that this +script assumes that the user is using a ramdisk image prepared for U-Boot, like +the ones provided by Linaro. If using a ramdisk without this header,the ``0x40`` +offset in ``INITRD_START`` has to be removed. + +.. code:: bash + + #!/bin/bash + + # Path to the input DTB + KERNEL_DTB=<path-to>/<fdt> + # Path to the output DTB + PATCHED_KERNEL_DTB=<path-to>/<patched-fdt> + # Base address of the ramdisk + INITRD_BASE=0x84000000 + # Path to the ramdisk + INITRD=<path-to>/<ramdisk.img> + + # Skip uboot header (64 bytes) + INITRD_START=$(printf "0x%x" $((${INITRD_BASE} + 0x40)) ) + INITRD_SIZE=$(stat -Lc %s ${INITRD}) + INITRD_END=$(printf "0x%x" $((${INITRD_BASE} + ${INITRD_SIZE})) ) + + CHOSEN_NODE=$(echo \ + "/ { \ + chosen { \ + linux,initrd-start = <${INITRD_START}>; \ + linux,initrd-end = <${INITRD_END}>; \ + }; \ + };") + + echo $(dtc -O dts -I dtb ${KERNEL_DTB}) ${CHOSEN_NODE} | \ + dtc -O dtb -o ${PATCHED_KERNEL_DTB} - + +And the FVP binary can be run with the following command: :: - <path-to>/FVP_Base_AEMv8A-AEMv8A \ - -C bp.secureflashloader.fname=bl1.bin \ - -C bp.flashloader0.fname=fip.bin \ - -a cluster0.cpu0=<bootwrapped-kernel.elf> \ - --start cluster0.cpu0=0x0 - -The ``-a cluster0.cpu0=<bootwrapped-kernel.elf>`` option loads the ELF file. It -also sets the PC register to the ELF entry point address, which is not the -desired behaviour, so the ``--start cluster0.cpu0=0x0`` option forces the PC back -to 0x0 (the BL1 entry point address) on CPU #0. The ``PRELOADED_BL33_BASE`` define -used when compiling the FIP must match the ELF entry point. - -Boot of a preloaded bootwrapped kernel image on Juno -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ - -The procedure to obtain and compile the boot wrapper is very similar to the case -of the FVP. The execution must be stopped at the end of bl2\_main(), and the -loading method explained above in the EL3 payload boot flow section may be used -to load the ELF file over JTAG on Juno. + <path-to>/FVP_Base_AEMv8A-AEMv8A \ + -C pctl.startup=0.0.0.0 \ + -C bp.secure_memory=1 \ + -C cluster0.NUM_CORES=4 \ + -C cluster1.NUM_CORES=4 \ + -C cache_state_modelled=1 \ + -C cluster0.cpu0.RVBAR=0x04020000 \ + -C cluster0.cpu1.RVBAR=0x04020000 \ + -C cluster0.cpu2.RVBAR=0x04020000 \ + -C cluster0.cpu3.RVBAR=0x04020000 \ + -C cluster1.cpu0.RVBAR=0x04020000 \ + -C cluster1.cpu1.RVBAR=0x04020000 \ + -C cluster1.cpu2.RVBAR=0x04020000 \ + -C cluster1.cpu3.RVBAR=0x04020000 \ + --data cluster0.cpu0="<path-to>/bl31.bin"@0x04020000 \ + --data cluster0.cpu0="<path-to>/<patched-fdt>"@0x82000000 \ + --data cluster0.cpu0="<path-to>/<kernel-binary>"@0x80080000 \ + --data cluster0.cpu0="<path-to>/<ramdisk.img>"@0x84000000 + +Boot of a preloaded kernel image on Juno +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +The Trusted Firmware must be compiled in a similar way as for FVP explained +above. The process to load binaries to memory is the one explained in +`Booting an EL3 payload on Juno`_. Running the software on FVP --------------------------- |