[PATCH v4 0/1] soc: fujitsu: Add A64FX diagnostic interrupt driver

[Hitomi Hasegawa]

The interrupt is set using pseudo-NMI if it is available. Arm has a
diagnostic interrupt feature called "Arm Generic Diagnostic Dump and
Reset device", but the A64FX does not support this feature and instead
has its own device definition.

I tested on FX700:
$ echo 1 > /proc/sys/kernel/sysrq
$ echo HARDLOCKUP > /sys/kernel/debug/provoke-crash/DIRECT
:
:

Send the "chassis power diag" command from the management server
using ipmitool, the following message is shown:
[  123.272342] Kernel panic - not syncing: a64fx_diag: interrupt received
:
:

Changes in V4:
 - Call the panic function instead of sysrq. Prepare a handler
   for each NMI/IRQ and call nmi_panic()/panic() respectively (as in v1).
 - Fixing other issues raised by Greg.

Changes in V3:
 - Exclude Sumit's patch.
 - Retest in v5.17.

Changes in V2:
 - Include Sumit's patch.
 - The handler calls handle_sysrq() to use the sysrq feature to cause
   a panic.
 - request_nmi() and request_irq() now use the same handler, and
   the function name of the handler has also changed.
 - Use readl()/writel() instead of readl_relaxed()/writel_relaxed().

V3: https://lore.kernel.org/linux-arm-kernel/20220331092235.3000787-1-hasegawa-hitomi@fujitsu.com/
V2: https://lore.kernel.org/linux-arm-kernel/20220304064324.331217-3-hasegawa-hitomi@fujitsu.com/
V1: https://lore.kernel.org/linux-arm-kernel/20220218092010.1327309-1-hasegawa-hitomi@fujitsu.com/


Hitomi Hasegawa (1):
  soc: fujitsu: Add A64FX diagnostic interrupt driver

 MAINTAINERS                      |   5 +
 drivers/soc/Kconfig              |   1 +
 drivers/soc/Makefile             |   1 +
 drivers/soc/fujitsu/Kconfig      |  13 +++
 drivers/soc/fujitsu/Makefile     |   3 +
 drivers/soc/fujitsu/a64fx-diag.c | 155 +++++++++++++++++++++++++++++++
 6 files changed, 178 insertions(+)
 create mode 100644 drivers/soc/fujitsu/Kconfig
 create mode 100644 drivers/soc/fujitsu/Makefile
 create mode 100644 drivers/soc/fujitsu/a64fx-diag.c

-- 
2.27.0