qemuboot, xen-image-minimal: enable runqemu for qemuarm64 Xen images

The Xen hypervisor built for Arm 64-bit targets can be launched with
runqemu by providing a Device Tree binary and configuration for Qemu,
which enables interactive testing of Xen images.

Add qemuboot-xen-dtb.bbclass to add a new bitbake task for generating
the dtb file by using lopper on a device tree produced by Qemu.

Add qemuboot-xen-defaults.bbclass to supply working default parameters
for the qemuarm64 machine and general support for qemuboot for Xen,
and adjust the defaults as needed to boot successfully in testing.

Development aided by this script by Stewart Hildebrand of DornerWorks:
https://gist.github.com/stewdk/110f43e0cc1d905fc6ed4c7e10d8d35e

Signed-off-by: Christopher Clark <christopher.clark@starlab.io>
Signed-off-by: Bruce Ashfield <bruce.ashfield@gmail.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/conf/distro/include/meta-virt-xen.inc b/conf/distro/include/meta-virt-xen.inc
index 02a78105..2becba15 100644
--- a/conf/distro/include/meta-virt-xen.inc
+++ b/conf/distro/include/meta-virt-xen.inc
@@ -10,3 +10,6 @@ XEN_RPI4_64_CONFIG_PATH ??= \
     'dynamic-layers/raspberrypi/conf/distro/include/xen-raspberrypi4-64.inc'
 include ${@bb.utils.contains('MACHINE', 'raspberrypi4-64', \
     '${XEN_RPI4_64_CONFIG_PATH}', '', d)}
+
+# Set serial for working qemuboot console
+SERIAL_CONSOLES_qemuarm64 ?= "115200;ttyAMA0"