[Qemu-devel] [PATCH 0/5] aspeed/timer: Fix slowdowns in recent Linux

[Cédric Le Goater]

Hello,

This series was initially sent by Andrew on the OpenBMC list :

  https://lists.ozlabs.org/pipermail/openbmc/2019-January/014640.html

We had an issue with the introduction of 4451d3f59f2a
("clocksource/drivers/fttmr010: Fix set_next_event handler") in Linux
where our QEMU Aspeed machine were becoming very slow.

The series' approach is to provide back-pressure and it has shown
significant improvement on the initial behavior which became normal
again.

Sorry for this last minute fix but I think it's worth merging for all
the QEMU Aspeed machine. It's a bit late for QEMU-4.0 so that might be
4.1 material.

Thanks,

C. 

Andrew Jeffery (3):
  aspeed/timer: Status register contains reload for stopped timer
  aspeed/timer: Fix match calculations
  aspeed/timer: Provide back-pressure information for short periods

Christian Svensson (1):
  aspeed/timer: Use signed muldiv for timer resets

Joel Stanley (1):
  aspeed/timer: Fix behaviour running Linux

 include/hw/timer/aspeed_timer.h |  1 +
 hw/misc/aspeed_scu.c            |  6 +++
 hw/timer/aspeed_timer.c         | 81 ++++++++++++++++++++-------------
 3 files changed, 57 insertions(+), 31 deletions(-)

-- 
2.20.1