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authorWill Deacon <will.deacon@arm.com>2017-10-24 16:05:15 +0100
committerWill Deacon <will.deacon@arm.com>2017-10-24 16:06:56 +0100
commit1e0c661f05ba0a3db52ed9debbe2b2e1d74aa0a4 (patch)
tree671d768cd8f177f2df05970fd799778753280f32 /Documentation
parent611479c79a94e6713bc044b0410aa8b867375d17 (diff)
parent07141342149a62db780c02f6352a0610a535eee1 (diff)
Merge branch 'for-next/perf' into aarch64/for-next/core
Merge in ARM PMU and perf updates for 4.15: - Support for the Statistical Profiling Extension - Support for Hisilicon's SoC PMU Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/devicetree/bindings/arm/spe-pmu.txt20
-rw-r--r--Documentation/perf/hisi-pmu.txt53
2 files changed, 73 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/arm/spe-pmu.txt b/Documentation/devicetree/bindings/arm/spe-pmu.txt
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+* ARMv8.2 Statistical Profiling Extension (SPE) Performance Monitor Units (PMU)
+
+ARMv8.2 introduces the optional Statistical Profiling Extension for collecting
+performance sample data using an in-memory trace buffer.
+
+** SPE Required properties:
+
+- compatible : should be one of:
+ "arm,statistical-profiling-extension-v1"
+
+- interrupts : Exactly 1 PPI must be listed. For heterogeneous systems where
+ SPE is only supported on a subset of the CPUs, please consult
+ the arm,gic-v3 binding for details on describing a PPI partition.
+
+** Example:
+
+spe-pmu {
+ compatible = "arm,statistical-profiling-extension-v1";
+ interrupts = <GIC_PPI 05 IRQ_TYPE_LEVEL_HIGH &part1>;
+};
diff --git a/Documentation/perf/hisi-pmu.txt b/Documentation/perf/hisi-pmu.txt
new file mode 100644
index 000000000000..267a028b2741
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+++ b/Documentation/perf/hisi-pmu.txt
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+HiSilicon SoC uncore Performance Monitoring Unit (PMU)
+======================================================
+The HiSilicon SoC chip includes various independent system device PMUs
+such as L3 cache (L3C), Hydra Home Agent (HHA) and DDRC. These PMUs are
+independent and have hardware logic to gather statistics and performance
+information.
+
+The HiSilicon SoC encapsulates multiple CPU and IO dies. Each CPU cluster
+(CCL) is made up of 4 cpu cores sharing one L3 cache; each CPU die is
+called Super CPU cluster (SCCL) and is made up of 6 CCLs. Each SCCL has
+two HHAs (0 - 1) and four DDRCs (0 - 3), respectively.
+
+HiSilicon SoC uncore PMU driver
+---------------------------------------
+Each device PMU has separate registers for event counting, control and
+interrupt, and the PMU driver shall register perf PMU drivers like L3C,
+HHA and DDRC etc. The available events and configuration options shall
+be described in the sysfs, see :
+/sys/devices/hisi_sccl{X}_<l3c{Y}/hha{Y}/ddrc{Y}>/, or
+/sys/bus/event_source/devices/hisi_sccl{X}_<l3c{Y}/hha{Y}/ddrc{Y}>.
+The "perf list" command shall list the available events from sysfs.
+
+Each L3C, HHA and DDRC is registered as a separate PMU with perf. The PMU
+name will appear in event listing as hisi_sccl<sccl-id>_module<index-id>.
+where "sccl-id" is the identifier of the SCCL and "index-id" is the index of
+module.
+e.g. hisi_sccl3_l3c0/rd_hit_cpipe is READ_HIT_CPIPE event of L3C index #0 in
+SCCL ID #3.
+e.g. hisi_sccl1_hha0/rx_operations is RX_OPERATIONS event of HHA index #0 in
+SCCL ID #1.
+
+The driver also provides a "cpumask" sysfs attribute, which shows the CPU core
+ID used to count the uncore PMU event.
+
+Example usage of perf:
+$# perf list
+hisi_sccl3_l3c0/rd_hit_cpipe/ [kernel PMU event]
+------------------------------------------
+hisi_sccl3_l3c0/wr_hit_cpipe/ [kernel PMU event]
+------------------------------------------
+hisi_sccl1_l3c0/rd_hit_cpipe/ [kernel PMU event]
+------------------------------------------
+hisi_sccl1_l3c0/wr_hit_cpipe/ [kernel PMU event]
+------------------------------------------
+
+$# perf stat -a -e hisi_sccl3_l3c0/rd_hit_cpipe/ sleep 5
+$# perf stat -a -e hisi_sccl3_l3c0/config=0x02/ sleep 5
+
+The current driver does not support sampling. So "perf record" is unsupported.
+Also attach to a task is unsupported as the events are all uncore.
+
+Note: Please contact the maintainer for a complete list of events supported for
+the PMU devices in the SoC and its information if needed.