	Xvisor on Allwinner A10 board (or Sun4i) using SD Booting 

This section of readme explains how to build & run Xvisor on actual Allwinner
A10 boards (Hackberry or pcduino for example) using SD booting feature of
Sun4i SOC.

By default, Xvisor for Sun4i supports Realview-PB-A8 guest so we will show
how to run Basic Firmware (and/or Linux) on Realview-PB-A8 guest.

As first step of SD booting on Sun4i SOC, we need to re-partition and program
a SD card (> 4GB card) with Uboot. For detailed info on preparing SD card for
booting refer: http://rhombus-tech.net/allwinner_a10/a10_mmc_boot

Once we have SD card prepared for SD booting, we add 3 images to the boot
partition of SD card:
 1) U-Boot compatible Xvisor binary (uvmm.bin)
 2) DTB for Xvisor (one_guest_pb-a8.dtb)
 3) Disk image containing guest binaries (disk.img)

Following are steps to create these images and then boot Xvisor on Allwinner
A10:

  [1. Build environment]
  # CROSS_COMPILE=arm-unknown-linux-gnueabi-

  [2. GoTo Xvisor source directory]
  # cd <xvisor_source_directory>

  [3. Configure Xvisor with Generic-v7 default settings]
  # make ARCH=arm generic-v7-defconfig

  [4. Build Xvisor and DTBs]
  # make; make dtbs

  [5. Make U-Boot compatible uvmm.bin for use with bootm command]
  # mkimage -A arm -O linux -T kernel -C none -a 0x40008000 -e 0x40008000 -n Xvisor -d build/vmm.bin build/uvmm.bin

  [6. Build Basic Firmware for Realview-PB-A8 Guest, this creates firmware.bin.patched]
  # make -C tests/arm32/realview-pb-a8/basic
  
  [7. Create disk image for Xvisor]
  # mkdir -p ./build/disk/images/arm32/realview-pb-a8
  # ./build/tools/dtc/dtc -I dts -O dtb -o ./build/disk/images/arm32/realview-pb-a8.dtb ./tests/arm32/realview-pb-a8/realview-pb-a8.dts
  # cp -f ./build/tests/arm32/realview-pb-a8/basic/firmware.bin.patched ./build/disk/images/arm32/realview-pb-a8/firmware.bin
  # cp -f ./tests/arm32/realview-pb-a8/basic/nor_flash.list ./build/disk/images/arm32/realview-pb-a8/nor_flash.list
  # genext2fs -B 1024 -b 16384 -d ./build/disk ./build/disk.img
  OR
  # mkdir -p ./build/disk/images/arm32/realview-pb-a8
  # ./build/tools/dtc/dtc -I dts -O dtb -o ./build/disk/images/arm32/realview-pb-a8.dtb ./tests/arm32/realview-pb-a8/realview-pb-a8.dts
  # cp -f ./build/tests/arm32/realview-pb-a8/basic/firmware.bin.patched ./build/disk/images/arm32/realview-pb-a8/firmware.bin
  # cp -f ./tests/arm32/realview-pb-a8/linux/nor_flash.list ./build/disk/images/arm32/realview-pb-a8/nor_flash.list
  # cp -f ./tests/arm32/realview-pb-a8/linux/cmdlist ./build/disk/images/arm32/realview-pb-a8/cmdlist
  # cp -f <linux_build_directory>/arch/arm/boot/Image ./build/disk/images/arm32/realview-pb-a8/Image
  # cp -f <busybox_rootfs_directory>/rootfs.img ./build/disk/images/arm32/rootfs.img
  # genext2fs -B 1024 -b 16384 -d ./build/disk ./build/disk.img

  (Note: For creating <linux_build_directory>/arch/arm/boot/Image refer
   <xvisor_source_directory>/tests/arm32/realview-pb-a8/linux/README)
  (Note: For creating <busybox_rootfs_directory>/rootfs.img refer
   <xvisor_source_directory>/tests/arm32/common/busybox/README)

  [8. Unplug bootable SD card from the A10 board and plug it on your development machine]

  [9. Mount boot partition (or partition 0) of SD card on your development machine]

  [10. Copy uvmm.bin to boot partition of SD card]
  # cp -f build/uvmm.bin <path_to_mounted_boot_partition_of_sd_card>
  # cp -f build/arch/arm/board/generic/dts/sun4i/hackberry/one_guest_pb-a8.dtb <path_to_mounted_boot_partition_of_sd_card>
  # cp -f build/disk.img <path_to_mounted_boot_partition_of_sd_card>

  [11. Unmount boot partition (or partition 0) of SD card from your development machine]

  [12. Unplug SD card from your development machine and plug it back on A10 board]

  [13. Connect to serial port of A10 board using Putty or Minicom]

  [14. Power-up or Reset A10 board and press any key when U-Boot shows auto-boot count down]

  [15. Enable MMC interface from U-Boot command line]
  sun4i# mmc dev 0:0

  [16. Copy Xvisor from SD card to SDRAM]
  sun4i# fatload mmc 0 0x40200000 uvmm.bin

  [17. Copy Xvisor DTB from SD card to SDRAM]
  sun4i# fatload mmc 0 0x40800000 one_guest_pb-a8.dtb

  [18. Copy disk image from SD card to SDRAM]
  sun4i# fatload mmc 0 0x41000000 disk.img

  [19. Jump into Xvisor after disabling MMU, interrupts, etc]
  sun4i# bootm 0x40200000 - 0x40800000

  [20. Kick Guest0 for starting Basic Firmware]
  XVisor# guest kick guest0

  [21. Bind to virtual UART]
  XVisor# vserial bind guest0/uart0

  [22. Say 'hi' to Basic Firmware]
  [guest0/uart0] basic# hi

  (Note: If you had linux images loaded in guest NOR flash
   then instead of above step you can start booting linux,
   basic# autoexec)

  [23. Say 'hello' to Basic Firmware]
  [guest0/uart0] basic# hello

  [24. Check various commands of Basic Firmware]
  [guest0/uart0] basic# help

  [25. Enter character seqence 'ESCAPE+x+q" return to Xvisor prompt]
  [guest0/uart0] basic# 

  (Note: replace all <> brackets based on your workspace)

