1 ARM Trusted Firmware for QEMU virt ARMv8-A 2 ========================================== 3 4 ARM Trusted Firmware implements the EL3 firmware layer for QEMU virt 5 ARMv8-A. BL1 is used as the BootROM, supplied with the -bios argument. 6 When QEMU starts all CPUs are released simultaneously, BL1 selects a 7 primary CPU to handle the boot and the secondaries are placed in a polling 8 loop to be released by normal world via PSCI. 9 10 BL2 edits the Flattened Device Tree, FDT, generated by QEMU at run-time to 11 add a node describing PSCI and also enable methods for the CPUs. 12 13 An ARM64 defonfig v4.5 Linux kernel is known to boot, FTD doesn't need to be 14 provided as it's generated by QEMU. 15 16 Current limitations: 17 18 - Only cold boot is supported 19 - No build instructions for QEMU\_EFI.fd and rootfs-arm64.cpio.gz 20 - No instructions for how to load a BL32 (Secure Payload) 21 22 ``QEMU_EFI.fd`` can be dowloaded from 23 http://snapshots.linaro.org/components/kernel/leg-virt-tianocore-edk2-upstream/latest/QEMU-KERNEL-AARCH64/RELEASE_GCC49/QEMU_EFI.fd 24 25 Boot binaries, except BL1, are primarily loaded via semi-hosting so all 26 binaries has to reside in the same directory as QEMU is started from. This 27 is conveniently achieved with symlinks the local names as: 28 29 - ``bl2.bin`` -> BL2 30 - ``bl31.bin`` -> BL31 31 - ``bl33.bin`` -> BL33 (``QEMU_EFI.fd``) 32 - ``Image`` -> linux/Image 33 34 To build: 35 36 :: 37 38 make CROSS_COMPILE=aarch64-none-elf- PLAT=qemu 39 40 To start (QEMU v2.6.0): 41 42 :: 43 44 qemu-system-aarch64 -nographic -machine virt,secure=on -cpu cortex-a57 \ 45 -kernel Image \ 46 -append console=ttyAMA0,38400 keep_bootcon root=/dev/vda2 \ 47 -initrd rootfs-arm64.cpio.gz -smp 2 -m 1024 -bios bl1.bin \ 48 -d unimp -semihosting-config enable,target=native 49
