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