[PATCH v7 0/6] Exynos-pmu: Generalise cpu{hotplug,idle},PMU intr gen and add Exynos850 CPU hotplug

[Alexey Klimov]

Series generalises the GS101-specific cpuhotplug, cpuidle and PMU interrupt
generation block support, which is currently implemented specifically for
the google GS101 SoC, to make it reusable by other Samsung Exynos SoCs.

The PMU interrupt generation IP block introduced for google GS101 is a
standard Samsung Exynos block found in other SoCs, including Exynos850,
and it is not strictly exclusive to google Exynos-based platforms.
Access to this block is required to implement and enable cpuhotplug
on Exynos850-based boards.

As a next steps it will be possible to enable idle states on top of it
(if we get our hands on correct firmware).

First patches work on DT bindings to reflect that Exynos850 SoC predates
gs101 one and adding mandatory property 'google,pmu-intr-gen-syscon'
for exynos850-pmu.
Then series generalises ("Exynosizes") cpuhotplug/cpuidle routines by
deferring platform-specific PMU and PMU-intr-gen updates to platform-
specific callbacks and then finally introduces new file exynos850-pmu.c
where such callbacks are implemented for Exynos850. Last commit adds
pmu_intr_gen DT node to exynos850.dtsi.

This series depends on
[PATCH v3] soc: samsung: exynos-pmu: fix error paths in cpuhotplug/idle states setup
https://lore.kernel.org/linux-samsung-soc/20260930-exynos-pmu-cpuhp-idle-fixes-v3-1-4269d8425978@xxxxxxxxxx/

Sashiko bot reported issues here:
https://sashiko.dev/#/patchset/20260513-exynos850-cpuhotplug-v4-0-54fec5f65362@xxxxxxxxxx?part=4

The are basically no updates in this v7 series, just a rebase on top of
an dependency patch.

This series was again re-tested on Exynos850 WinLink E850-96 board:
-- by spinning "chcpu -d 1-7; chcpu -e 1-7" in a loop for a few hours;
-- by running script [1] that randomly offlines or onlines random cpus
   for a few hours.

Thanks to Peter for testing!

Thanks,
Alexey

[1]: https://github.com/laklimov/xlam/blob/main/e850_cpuhotplug_random.sh

Signed-off-by: Alexey Klimov <alexey.klimov@xxxxxxxxxx>
---
Changes in v7:
- rebased on top of -next and patch (it is dependency):
  [PATCH v3] soc: samsung: exynos-pmu: fix error paths in cpuhotplug/idle states setup;
- retested;
- Link to v6: https://lore.kernel.org/r/20260902-exynos850-cpuhotplug-v6-0-a85bb55bb118@xxxxxxxxxx

Changes in v6:
- rebase on top -next and "fixes" series, basically no other updates;
- Link to v5: https://lore.kernel.org/r/20260609-exynos850-cpuhotplug-v5-0-8422cf80d43b@xxxxxxxxxx

Changes in v5:
- updated the commit message of ("soc: samsung: exynos-pmu: add Exynos850
  CPU hotplug support");
- the if-check for the presense of pmu_data->cpu_pmu_{offline,online}
  callbacks in setup_cpuhp_and_cpuidle() was moved to before acquiring ref
  counter to intr_gen_node (the initial issue was reported by Sashiko);
- added pr_fmt to exynos850-pmu.c to have more meaningful error
  messages;
- added parentheses around the `cl` in `EXYNOS850_CLUSTER_CPU_OFFSET` macro
  (as suggested by Sashiko bot);
- custom syscon regmap with raw_spinlocks for pmu offline/online callbacks
  (the initial issue was reported by Sashiko);
- using topology_cluster_id() and topology_core_id() in exynos850-pmu.c
  (the initial issue was reported by Sashiko);
- removed smp_processor_id() usage fomr pmu offline/online callbacks
  (the initial issue was reported by Sashiko);
- added/resorted headers in exynos850-pmu.c;
- Link to v4: https://lore.kernel.org/r/20260513-exynos850-cpuhotplug-v4-0-54fec5f65362@xxxxxxxxxx

Changes in v4:
- remove blank line in file exynos850-pmu.c, commit (as suggested by Krzysztof);
- only update trailers/tags in commit messages;
- Link to v3: https://lore.kernel.org/r/20260430-exynos850-cpuhotplug-v3-0-fd6251d02a17@xxxxxxxxxx

Changes in v3:
- dropped two commits where samsung,pmu-intr-gen phandle is introduced and
  where google,pmu-intr-gen-syscon is deprecated (as suggested by Rob Herring);
- addtion to maintainers file was moved to separate entry, change commit message;
- commit message in "generalise gs101-specific cpu{idle,hotplug} for Exynos SoCs"
  was updated since it no longer touches samsung,pmu-intr-gen-syscon;
- added missing asm/cputype.h header to exynos850-pmu.h
  (reported by Henrik Grimler);
- new commit "dt-bindings: soc: samsung: exynos-pmu: Require
  pmu-intr-gen-syscon for Exynos850";
- Link to v2: https://lore.kernel.org/r/20260401-exynos850-cpuhotplug-v2-0-c5a760a3e259@xxxxxxxxxx

Changes in v2:
- moved gs101 cpu {offline,online} callbacks to gs101-pmu.c, updated MAINTAINERS;
- added new file exynos850-pmu.c with cpu {offline,online} callbacks and
  exynos850 pmu data;
- new patch that adds exynos850-pmu.c to MAINTAINERS;
- moved pmu_intr_gen to right after pmu_system_controller@11860000;
- merged two patches that update google,gs101-pmu-intr-gen.yaml together,
  now rename and adding exynos850 entry goes in a single patch;
- commits 5 and 6 from RFC series are merged together and reworked,
  cpu_pmu_{offline,online} callbacks are moved into pmu_data struct, and
  callbacks now need pmu_context as an argument, exynos_pmu_context and
  CPU_INFORM defines are moved to exynos-pmu.h, gs101 callbacks
  renamed. It is really better to check commit description.
- Link to RFC (v1 from b4 point of view):
  https://lore.kernel.org/r/20260226-exynos850-cpuhotplug-v1-0-71d7c4063382@xxxxxxxxxx

---
Alexey Klimov (6):
      dt-bindings: soc: move,rename google,gs101-pmu-intr-gen and add exynos850
      dt-bindings: soc: samsung: exynos-pmu: Require pmu-intr-gen-syscon for Exynos850
      soc: samsung: exynos-pmu: generalise gs101-specific cpu{idle,hotplug} for Exynos SoCs
      soc: samsung: exynos-pmu: add Exynos850 CPU hotplug support
      MAINTAINERS: add Exynos850 PMU entry
      arm64: dts: exynos850: add PMU interrupt generation node

 .../bindings/soc/samsung/exynos-pmu.yaml           |   1 +
 .../samsung,exynos850-pmu-intr-gen.yaml}           |   8 +-
 MAINTAINERS                                        |   9 +-
 arch/arm64/boot/dts/exynos/exynos850.dtsi          |   6 +
 drivers/soc/samsung/Makefile                       |   2 +-
 drivers/soc/samsung/exynos-pmu.c                   | 149 +++++++--------------
 drivers/soc/samsung/exynos-pmu.h                   |  34 +++++
 drivers/soc/samsung/exynos850-pmu.c                |  95 +++++++++++++
 drivers/soc/samsung/gs101-pmu.c                    |  51 +++++++
 include/linux/soc/samsung/exynos-regs-pmu.h        |  15 ++-
 10 files changed, 260 insertions(+), 110 deletions(-)
---
base-commit: 6375e61c01e93e35ee7acd336a689ac1fae4b509
change-id: 20260226-exynos850-cpuhotplug-69f1976eefa8
prerequisite-message-id: 20260930-exynos-pmu-cpuhp-idle-fixes-v3-1-4269d8425978@xxxxxxxxxx
prerequisite-patch-id: d9ac215f16060e07e9cfe193e7c9af7c8913bdae

Best regards,
-- 
Alexey Klimov <alexey.klimov@xxxxxxxxxx>