On 19/2/24 14:33, Mark Cave-Ayland wrote:
On 19/02/2024 13:05, Peter Maydell wrote:
On Mon, 19 Feb 2024 at 12:49, Mark Cave-Ayland
<mark.cave-ayland@xxxxxxxxxxxx> wrote:
On 19/02/2024 12:00, BALATON Zoltan wrote:
For new people trying to contribute to QEMU QDev is overwhelming so
having some way
to need less of it to do simple things would help them to get started.
It depends what how you define "simple": for QEMU developers most
people search for
similar examples in the codebase and copy/paste them. I'd much rather
have a slightly
longer, but consistent API for setting properties rather than coming
up with many
special case wrappers that need to be maintained just to keep the
line count down for
"simplicity".
I think that Phil's approach here is the best one for now,
particularly given that it
allows us to take another step towards heterogeneous machines. As the
work in this
area matures it might be that we can consider other approaches, but
that's not a
decision that can be made right now and so shouldn't be a reason to
block this change.
Mmm. It's unfortunate that we're working with C, so we're a bit limited
in what tools we have to try to make a better and lower-boilerplate
interface for the "create, configure, realize and wire up devices" task.
(I think you could do much better in a higher level language...)
sysbus_create_simple() was handy at the time, but it doesn't work so
well for more complicated SoC-based boards. It's noticeable that
if you look at the code that uses it, it's almost entirely the older
and less maintained board models, especially those which don't actually
model an SoC and just have the board code create all the devices.
Yeah I was thinking that you'd use the DSL (e.g. YAML templates or
similar) to provide some of the boilerplating around common actions,
rather than the C API itself. Even better, once everything has been
moved to use a DSL then the C API shouldn't really matter so much as it
is no longer directly exposed to the user.
Something similar was discussed with Markus and Manos. Although the
first step we noticed is to unify the QDev API -- making it verbose --
to figure what we need to expose in the DSL. Doing it the other way
(starting a DSL and trying to adapt it to all QEMU models) seemed a
waste of time. At least for our current human resources.
