Support for QEMU virt ARM 32

[Lucas Stach]

Am Donnerstag, den 30.11.2017, 17:39 +0100 schrieb Andre Wagner:
> 
> On 30.11.2017 15:53, Lucas Stach wrote:
> > Hi André,
> > 
> > Am Donnerstag, den 30.11.2017, 15:29 +0100 schrieb Andre Wagner:
> > > Hello everyone,
> > > 
> > > I'm trying to add support for the Qemu virt ARM32 machine (qemu
> > > version
> > > 2.10) based on the existing Qemu virt ARM64 support. In my
> > > understanding
> > > the emulated CPU is only a ARMv7 CPU instead of a ARMv8 CPU. Is
> > > this
> > > correct?
> > 
> > VExpress is the generic ARM32 QEMU platform. Barebox already
> > supports
> > that. Check out the last release (as it has some improvements in
> > that
> > area), and build the vexpress_defconfig.
> > 
> > To run the emulated platform take a look at
> > Documentation/boards/arm-
> > qemu-vexpress.rst
> > 
> > Regards,
> > Lucas
> 
> Thank you very much for the fast reply, I got a barebox working with 
> vexpress on Qemu now! Just a question (little bit off topic): The
> Qemu 
> virt ARM64 barebox version is called with: qemu-system-aarch64 -m
> 2048M 
> -cpu cortex-a57 -machine virt -display none -serial stdio -kernel 
> ../barebox/barebox (according to 
> http://barebox.org/doc/latest/boards/aarch64-qemu-virt.html). The
> first 
> tests I did were starting my broken barebox version with qemu-system-
> arm 
> -m 2048M -cpu cortex-a15 -machine virt -display none -serial stdio 
> -kernel ../barebox/barebox. Is this 'virt' machine not the _real_
> Qemu 
> virt ARM32?

virt is a generic virtual platform and doesn't resemble any real
hardware. This is nice for some use-cases, as it doesn't have the
restrictions of real hardware systems, but then most of the peripherals
are virtio or mapped on a virtual PCI bus. Barebox is lacking driver
support for most of those peripherals, so the usefulness of this
machine is limited when used with Barebox.

See also: https://wiki.qemu.org/Documentation/Platforms/ARM

Regards,
Lucas