QEMU Community Call 13th Feb [Minutes]

QEMU Community Call 13th Feb [Minutes]

[Philippe Mathieu-Daudé]

Attendees:
- Philippe Mathieu-Daudé
- Markus Armbruster
- Anton Johansson
- Manos Pitsidianakis
- Paul Walmsley & SiFive QEMU team

Notes:
- Discussion on introducing a WIRING step in QDEV realization steps
   https://lore.kernel.org/all/20240209123226.32576-1-philmd@linaro.org/
   Bus-based devices already do something similar (IRQ wiring) in their
   BusRealize handler (i.e. PCI). MMIO mapping is usually done explicitly
   in-band, triggered by the guest.

- Make some QDev properties "configurable-only" then "read-only"
   https://lore.kernel.org/all/20211103173002.209906-1-kwolf@redhat.com/

- Steps in dynamic machine / heterogeneous emulation per last week call
   https://wiki.qemu.org/Dynamic_machine_and_heterogeneous_emulation_roadmap

- No objection to adding new binary we can use to prototype
 
https://lore.kernel.org/qemu-devel/20240209152945.25727-1-philmd@linaro.org/
   Suggestion to use QOM interface to prototype API changes and
   avoid to convert the whole tree.
   Watch out to not end with never finished conversions.

- Leverage QOM interfaces when inheritance pattern doesn't work
 
https://lore.kernel.org/all/20240212174925.1504899-1-peter.maydell@linaro.org/
   Why can't we model the reset tree with QDev?
   Maybe be needed for RESET because MachineState isn't QDev.

- SiFive already using QMP to create dynamic machine and using
   heterogeneous emulation using old patches from Xilinx / Edgar
   Iglesias. Team definitively interested. Possibility to help
   in few weeks when team get more comfortable with community.

- We might let the current Tuesday QEMU community call for generic
   topics and add an extra "dynamic machine / heterogeneous emulation"
   quick call every Thursday

Action items:
[ ] Setup a community calendar invite!
[ ] Next meeting next week