[RFC PATCH-for-6.1 0/9] hw/clock: Strengthen machine (non-qdev) clock propagation

[Philippe Mathieu-Daudé]

Hi Damian, Luc, Peter.

I've been debugging some odd issue with the clocks:
a clock created in the machine (IOW, not a qdev clock) isn't
always resetted, thus propagating its value.
"not always" is the odd part. In the MPS2 board, the machine
clock is propagated. Apparently because the peripherals are
created directly in the machine_init() handler. When moving
them out in a SoC QOM container, the clock isn't... I'm still
having hard time to understand what is going on.

Alternatively I tried to strengthen the clock API by reducing
the clock creation in 2 cases: machine/device. This way clocks
aren't left dangling around alone. The qdev clocks are properly
resetted, and for the machine clocks I register a generic reset
handler. This way is safer, but I don't think we want to keep
adding generic reset handlers, instead we'd like to remove them.

I'll keep debugging to understand. Meanwhile posting this series
as RFC to get feedback on the approach and start discussing on
this issue.

Regards,

Phil.

Philippe Mathieu-Daudé (9):
  hw/core/clock: Increase clock propagation trace events verbosity
  hw/core/machine: Add machine_create_constant_clock() helper
  hw/arm: Use new machine_create_constant_clock() helper
  hw/mips: Use new machine_create_constant_clock() helper
  hw/core/qdev-clock: Add qdev_ground_clock() helper
  hw/misc/bcm2835_cprman: Use qdev_ground_clock() helper
  hw/misc/bcm2835_cprman: Feed 'xosc' from the board
  hw/clock: Declare clock_new() internally
  hw/core/machine: Reset machine clocks using qemu_register_reset()

 hw/core/clock-internal.h         | 32 ++++++++++++++++++++++++++++++++
 include/hw/boards.h              | 17 +++++++++++++++++
 include/hw/clock.h               | 13 -------------
 include/hw/misc/bcm2835_cprman.h |  2 --
 include/hw/qdev-clock.h          |  9 +++++++++
 hw/arm/bcm2835_peripherals.c     |  1 +
 hw/arm/bcm2836.c                 |  1 +
 hw/arm/mps2-tz.c                 |  6 ++----
 hw/arm/mps2.c                    |  3 +--
 hw/arm/musca.c                   |  6 ++----
 hw/arm/raspi.c                   |  4 ++++
 hw/core/clock.c                  |  9 ++++++++-
 hw/core/machine.c                | 20 ++++++++++++++++++++
 hw/core/qdev-clock.c             | 12 ++++++++++++
 hw/mips/fuloong2e.c              |  4 ++--
 hw/mips/jazz.c                   |  6 +++---
 hw/mips/loongson3_virt.c         |  4 ++--
 hw/mips/mipssim.c                |  7 ++++---
 hw/misc/bcm2835_cprman.c         | 12 +++---------
 MAINTAINERS                      |  1 +
 hw/core/trace-events             |  3 ++-
 21 files changed, 126 insertions(+), 46 deletions(-)
 create mode 100644 hw/core/clock-internal.h

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