README.qemu-arm 2.5 KB

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  1. # SPDX-License-Identifier: GPL-2.0+
  2. #
  3. # Copyright (C) 2017, Tuomas Tynkkynen <tuomas.tynkkynen@iki.fi>
  4. U-Boot on QEMU's 'virt' machine on ARM & AArch64
  5. ================================================
  6. QEMU for ARM supports a special 'virt' machine designed for emulation and
  7. virtualization purposes. This document describes how to run U-Boot under it.
  8. Both 32-bit ARM and AArch64 are supported.
  9. The 'virt' platform provides the following as the basic functionality:
  10. - A freely configurable amount of CPU cores
  11. - U-Boot loaded and executing in the emulated flash at address 0x0
  12. - A generated device tree blob placed at the start of RAM
  13. - A freely configurable amount of RAM, described by the DTB
  14. - A PL011 serial port, discoverable via the DTB
  15. - An ARMv7/ARMv8 architected timer
  16. - PSCI for rebooting the system
  17. - A generic ECAM-based PCI host controller, discoverable via the DTB
  18. Additionally, a number of optional peripherals can be added to the PCI bus.
  19. Building U-Boot
  20. ---------------
  21. Set the CROSS_COMPILE environment variable as usual, and run:
  22. - For ARM:
  23. make qemu_arm_defconfig
  24. make
  25. - For AArch64:
  26. make qemu_arm64_defconfig
  27. make
  28. Running U-Boot
  29. --------------
  30. The minimal QEMU command line to get U-Boot up and running is:
  31. - For ARM:
  32. qemu-system-arm -machine virt -bios u-boot.bin
  33. - For AArch64:
  34. qemu-system-aarch64 -machine virt -cpu cortex-a57 -bios u-boot.bin
  35. Note that for some odd reason qemu-system-aarch64 needs to be explicitly
  36. told to use a 64-bit CPU or it will boot in 32-bit mode.
  37. Additional persistent U-boot environment support can be added as follows:
  38. - Create envstore.img using qemu-img:
  39. qemu-img create -f raw envstore.img 64M
  40. - Add a pflash drive parameter to the command line:
  41. -drive if=pflash,format=raw,index=1,file=envstore.img
  42. Additional peripherals that have been tested to work in both U-Boot and Linux
  43. can be enabled with the following command line parameters:
  44. - To add a Serial ATA disk via an Intel ICH9 AHCI controller, pass e.g.:
  45. -drive if=none,file=disk.img,id=mydisk -device ich9-ahci,id=ahci -device ide-drive,drive=mydisk,bus=ahci.0
  46. - To add an Intel E1000 network adapter, pass e.g.:
  47. -netdev user,id=net0 -device e1000,netdev=net0
  48. - To add an EHCI-compliant USB host controller, pass e.g.:
  49. -device usb-ehci,id=ehci
  50. - To add a NVMe disk, pass e.g.:
  51. -drive if=none,file=disk.img,id=mydisk -device nvme,drive=mydisk,serial=foo
  52. These have been tested in QEMU 2.9.0 but should work in at least 2.5.0 as well.