RE: how to add a new machine?

[ckim]

Hi, Peter Maydell
Thank you very much for the information.
Those are all very helpful information for me.
Thank you!
Chan Kim

> -----Original Message-----
> From: Peter Maydell <peter.maydell@linaro.org>
> Sent: Wednesday, February 17, 2021 8:12 PM
> To: Chan Kim <ckim@etri.re.kr>
> Cc: qemu-discuss <qemu-discuss@nongnu.org>
> Subject: Re: how to add a new machine?
> 
> On Wed, 17 Feb 2021 at 09:39, <ckim@etri.re.kr> wrote:
> >
> > Hello, very clever qemu developers,
> >
> >
> >
> > For our SoC development, I decided to make our new machine to play
> > with. (It’ll be a long term job)
> >
> > Let’s call the new machine ababa here.
> >
> > I thought just copying a machine will be easy, so I added these files
> below.
> >
> > l  hw/arm/ababa.c
> >
> > l  include/hw/arm/ababa.h
> >
> > l  hw/arm/ababa-acpi-build.c
> 
> This suggests that you're modifying the 'virt' board. That is not a good
> template to use for a model of an SoC, because the virt board is purely
> virtual, and has no SoC at all, and also has a lot of complicated stuff
> related to ACPI, to dtb generation, and to versioned machine types, which
> a simple "model of real hardware"
> does not require. The aspeed boards are probably a good example of a
> recently-implemented well-maintained SoC based set of boards.
> 
> > and modified these files to add that machine ababa during the build.
> >
> > l  default-configs/arm-softmmu.mak,
> 
> > l  hw/arm/Kconfig
> 
> > l  hw/arm/Makefile.objs
> 
> This suggests that you're modifying an old version of QEMU.
> If you're trying to do development like adding a new board model, you
> should usually be working with the head-of-QEMU-git.
> 
> > So at least it compiles ok. But when I tried running an example kernel
> > (which boots ok on ‘virt’) on the ‘ababa’ machine,
> >
> > “Qemu gave me this error message. “qemu-system-aarch64 -M ababa :
> unsupported machine type.”
> 
> This means that either (a) you failed to correctly modify the build system
> to actually build your ababa.c file, or
> (b) your ababa.c file didn't actually register a machine type with the
> right name. The -M option simply looks for every registered subclass of
> TYPE_MACHINE, so you don't need to explicitly add your new machine to any
> list.
> 
> thanks
> -- PMM