[0/6] perf: Arm SMMU PMU driver

Message

Robin Murphy Feb. 17, 2022, 2:24 p.m. UTC

Hi all,

Since our friends at Linaro had some interest in the area, I've dug up
and finished off my old SMMUv1/v2 PMU driver, now with a slightly less
terrible DT binding to boot. Patch #1 involves a general refactoring of
the IRQ setup code in arm-smmu which also now serves to remove the
general dependency on explicit IRQ resources for of_platform devices.

ACPI support via IORT (patch #2) is pleasingly trivial, but does have a
hard dependency on the previous patch, otherwise SMMU context
interrupts may get messed up.

The driver itself in patch #5 is still largely a time capsule of me
learning the PMU APIs 5 years ago (as a warm-up for arm-cmn). I've
mostly just added IRQ affinity support (which I didn't yet fully
understand at the time) and tweaked a few comments. I'm pretty confident
all the testing I did back then is still valid, so I've just run some
quick sanity checks with patch #6 to verify the new DT binding.

Cheers,
Robin.


Robin Murphy (6):
  iommu/arm-smmu: Account for PMU interrupts
  acpi/iort: Register SMMUv2 PMU interrupts
  iommu/arm-smmu: Add DT PMU support
  iommu/smmu: Create child devices for PMUs
  perf: Add ARM SMMU PMU driver
  arm64: dts: Add SMMU PMUs to Juno

 .../devicetree/bindings/iommu/arm,smmu.yaml   |  19 +-
 arch/arm64/boot/dts/arm/juno-base.dtsi        |  26 +-
 drivers/acpi/arm64/iort.c                     |  18 +-
 drivers/iommu/arm/arm-smmu/arm-smmu.c         | 143 ++--
 drivers/iommu/arm/arm-smmu/arm-smmu.h         |   5 +-
 drivers/perf/Kconfig                          |  24 +-
 drivers/perf/Makefile                         |   1 +
 drivers/perf/arm-smmu-pmu.c                   | 732 ++++++++++++++++++
 8 files changed, 896 insertions(+), 72 deletions(-)
 create mode 100644 drivers/perf/arm-smmu-pmu.c

Comments

Will Deacon March 7, 2022, 10:03 p.m. UTC | #1

On Thu, 17 Feb 2022 14:24:14 +0000, Robin Murphy wrote:
> Since our friends at Linaro had some interest in the area, I've dug up
> and finished off my old SMMUv1/v2 PMU driver, now with a slightly less
> terrible DT binding to boot. Patch #1 involves a general refactoring of
> the IRQ setup code in arm-smmu which also now serves to remove the
> general dependency on explicit IRQ resources for of_platform devices.
> 
> ACPI support via IORT (patch #2) is pleasingly trivial, but does have a
> hard dependency on the previous patch, otherwise SMMU context
> interrupts may get messed up.
> 
> [...]

Applied first patch to will (for-joerg/arm-smmu/updates), thanks!

[1/6] iommu/arm-smmu: Account for PMU interrupts
      https://git.kernel.org/will/c/97dfad194ca8

Cheers,