Arm Versatile Express boards (
QEMU models two variants of the Arm Versatile Express development board family:
vexpress-a9models the combination of the Versatile Express motherboard and the CoreTile Express A9x4 daughterboard
vexpress-a15models the combination of the Versatile Express motherboard and the CoreTile Express A15x2 daughterboard
Note that as this hardware does not have PCI, IDE or SCSI, the only available storage option is emulated SD card.
PL181 SD controller
PL050 keyboard and mouse
PL111 LCD display controller
SP810 system control block
USB controller (Philips ISP1761)
Local DAP ROM
PL301 AXI interconnect
HDLCD controller (
PL341 dynamic memory controller
DMA330 DMA controller
PL354 static memory controller
BP147 TrustZone Protection Controller
TrustZone Address Space Controller
Other differences between the hardware and the QEMU model:
QEMU will default to creating one CPU unless you pass a different
QEMU allows the amount of RAM provided to be specified with the
QEMU defaults to providing a CPU which does not provide either TrustZone or the Virtualization Extensions: if you want these you must enable them with
QEMU provides 4 virtio-mmio virtio transports; these start at address
vexpress-a15, and have IRQs from 40 upwards. If a dtb is provided on the command line then QEMU will edit it to include suitable entries describing these transports for the guest.
Booting a Linux kernel¶
Building a current Linux kernel with
multi_v7_defconfig should be
enough to get something running. Nowadays an out-of-tree build is
recommended (and also useful if you build a lot of different targets).
In the following example $BLD points to the build directory and $SRC
points to the root of the Linux source tree. You can drop $SRC if you
are running from there.
$ make O=$BLD -C $SRC ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- multi_v7_defconfig $ make O=$BLD -C $SRC ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf-
By default you will want to boot your rootfs off the sdcard interface. Your rootfs will need to be padded to the right size. With a suitable DTB you could also add devices to the virtio-mmio bus.
$ qemu-system-arm -cpu cortex-a15 -smp 4 -m 4096 \ -machine type=vexpress-a15 -serial mon:stdio \ -drive if=sd,driver=file,filename=armel-rootfs.ext4 \ -kernel zImage \ -dtb vexpress-v2p-ca15-tc1.dtb \ -append "console=ttyAMA0 root=/dev/mmcblk0 ro"