Hello all, I'm trying to run u-boot and linux on qemu arm64 virt machine preferably without changing any source code. (u-boot v2022.07, linux 5.15.68, qemu 6.2.0, busybox 1.32.1) I have built u-boot using qemu_arm64_defconfig and I got u-boot(elf) and u-boot.bin. I built linux using defconfig but later I removed many CONFIG_* to reduce compile time and got Image(binary). Also, I built busybox and made ramdisk. Now this is the qemu command I used. (I referenced u-boot's include/configs/qemu-arm.h to determine the load addresses, set CONFIG_BOOTCOMMAND=" booti 0x40400000 0x44000000 0x40000000") ../temp/qemu-6.2.0/build/aarch64-softmmu/qemu-system-aarch64 -machine virt,gic-version=max,secure=on,virtualization=true -cpu max -m 4G -nographic -bios u-boot/u-boot.bin -device loader,file=../temp/linux-5.15.68/arch/arm64/boot/Image,addr=0x40400000 -device loader,file=initrd.img,addr=0x44000000 u-boot runs and automatically boots linunx and it boots OK to the shell prompt. But at the linux shell prompt, it doesn't respond to my keyboard input. It looks like the symptom I saw last year when system counter is not working(for real board only). (I added system counter device in our qemu virtual machine just to not cause panic during the system counter access with the same driver. The qemu machine for our board runs ok using u-boot-spl and linux after booting including shell program and simple driver test. I'm trying to use u-boot proper now). Also last year I had to power-on the GICR(for virtual machine and real board). So I tried adding the code to power up GICR but it is the same. (this part is missing in u-boot, but I saw it is in the arm-tf S/W). For your reference this is the change in u-boot's arch/arm/lib/gic_64.S. /* x9: ReDistributor Base Address of Current CPU */ 2: mov w10, #~0x2 ldr w11, [x9, GICR_WAKER] and w11, w11, w10 /* Clear ProcessorSleep */ str w11, [x9, GICR_WAKER] dsb st isb ==> /* x9: ReDistributor Base Address of Current CPU */ 2: // gicr power on, ckim mov w10, 2 str w10, [x9, GICR_PWRR] 5: ldr w10, [x9, GICR_PWRR] tbnz w10, #1, 5b /* Wait Children be Alive */ mov w10, #~0x2 ldr w11, [x9, GICR_WAKER] and w11, w11, w10 /* Clear ProcessorSleep */ str w11, [x9, GICR_WAKER] dsb st isb Can anyone suggest what I can try to solve this problem? (I mean, the problem of linux shell not responding in qemu virtual machine) I would appreciate it for any comment or help. Thank you. Chan Kim