[PATCH v1 0/6] SiFive cache controller PMU drivers

Samuel Holland
2024-02-16T00:08:40Z

This patch series adds bindings and drivers for the Performance
Monitoring Units (PMUs) found in three SiFive cache controllers.

Composable Cache and Extensible Cache support system-wide profiling
with a single hardware instance. Private L2 Cache supports per-task
profiling with a separate hardware instance per core.

All three PMUs have a similar register interface and event encoding,
though the set of supported events is different. The Extensible Cache
additionally contains a pmCounterInhibit register which allows
atomically monitoring multiple counters.

All three of these cache controllers (with PMUs) have been integrated in
SoCs by our customers. However, as none of those SoCs have been publicly
announced yet, I cannot include SoC-specific compatible strings in this
version of the devicetree bindings.

This series is a follow-up to Eric Lin's series "[PATCH v2 0/3] Add
SiFive Private L2 cache and PMU driver":
https://lore.kernel.org/linux-riscv/20230720135125.21240-1-eric.lin@sifive.com/

Changes in v1:
- Add back select: clause to binding
- Make sifive,pl2cache1 the fallback for sifive,pl2cache0
- Fix the order of the reg property declaration
- Document the sifive,perfmon-counters property
- Drop the non-PMU part of the PL2 cache driver, as the config register
save/restore logic will be moved to M-mode
- Add missing events to PL2 sets 2, 4, and 5
- Use event_base and config_base to precompute register addresses
- Check event validity earlier, in the .event_init hook
- Implement .filter for systems where only some CPUs have a PL2
- Only allocate percpu data when probing each PL2 instance
- Reference count the `struct pmu` to fix unbind/bind crashes
- Probe via DT since the PMU driver is now the only PL2 driver
- Allow the driver to be built as a module

Eric Lin (4):
drivers/perf: Add SiFive Composable Cache PMU driver
dt-bindings: cache: Add SiFive Extensible Cache controller
drivers/perf: Add SiFive Extensible Cache PMU driver
dt-bindings: cache: Add SiFive Private L2 Cache controller

Greentime Hu (1):
drivers/perf: Add SiFive Private L2 Cache PMU driver

Samuel Holland (1):
dt-bindings: cache: Document the sifive,perfmon-counters property

.../bindings/cache/sifive,ccache0.yaml | 5 +
.../cache/sifive,extensiblecache0.yaml | 136 ++++
.../bindings/cache/sifive,pl2cache0.yaml | 81 ++
drivers/perf/Kconfig | 29 +
drivers/perf/Makefile | 3 +
drivers/perf/sifive_ccache_pmu.c | 577 ++++++++++++++
drivers/perf/sifive_ecache_pmu.c | 675 ++++++++++++++++
drivers/perf/sifive_pl2_pmu.c | 748 ++++++++++++++++++
include/linux/cpuhotplug.h | 2 +
9 files changed, 2256 insertions(+)
create mode 100644 Documentation/devicetree/bindings/cache/sifive,extensiblecache0.yaml
create mode 100644 Documentation/devicetree/bindings/cache/sifive,pl2cache0.yaml
create mode 100644 drivers/perf/sifive_ccache_pmu.c
create mode 100644 drivers/perf/sifive_ecache_pmu.c
create mode 100644 drivers/perf/sifive_pl2_pmu.c

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2.43.0