[PATCH v5 00/19] coresight: Add support for ETE and TRBE
Suzuki K Poulose
suzuki.poulose at arm.com
Tue Mar 23 12:06:28 GMT 2021
This series enables future IP trace features Embedded Trace Extension
(ETE) and Trace Buffer Extension (TRBE). This series applies on
v5.12-rc4 + some patches queued. A standalone tree is also available here [0].
The queued patches (almost there) are included in this posting for
the sake of constructing a tree from the posting.
ETE is the PE (CPU) trace unit for CPUs, implementing future
architecture extensions. ETE overlaps with the ETMv4 architecture, with
additions to support the newer architecture features and some restrictions
on the supported features w.r.t ETMv4. The ETE support is added by extending
the ETMv4 driver to recognise the ETE and handle the features as exposed by
the TRCIDRx registers. ETE only supports system instructions access from the
host CPU. The ETE could be integrated with a TRBE (see below), or with
the legacy CoreSight trace bus (e.g, ETRs). Thus the ETE follows same
firmware description as the ETMs and requires a node per instance.
Trace Buffer Extensions (TRBE) implements a per CPU trace buffer, which
is accessible via the system registers and can be combined with the ETE to
provide a 1x1 configuration of source & sink. TRBE is being represented
here as a CoreSight sink. Primary reason is that the ETE source could
work with other traditional CoreSight sink devices. As TRBE captures the
trace data which is produced by ETE, it cannot work alone.
TRBE representation here have some distinct deviations from a
traditional CoreSight sink device. Coresight path between ETE and TRBE are
not built during boot looking at respective DT or ACPI entries.
Unlike traditional sinks, TRBE can generate interrupts to signal
including many other things, buffer got filled. The interrupt is a PPI and
should be communicated from the platform. DT or ACPI entry representing TRBE
should have the PPI number for a given platform. During perf session, the
TRBE IRQ handler should capture trace for perf auxiliary buffer before restarting
it back. System registers being used here to configure ETE and TRBE could
be referred in the link below.
https://developer.arm.com/docs/ddi0601/g/aarch64-system-registers.
[0] https://gitlab.arm.com/linux-arm/linux-skp/-/tree/coresight/ete/v5/
Changes since V4:
https://lkml.kernel.org/r/20210225193543.2920532-1-suzuki.poulose@arm.com
- Split the documentation patches from the TRBE driver
- Drop the patches already queued for v5.12.
- Mark the buffer TRUNCATED in case of a WRAP event
- Fix error code for vmap failure
- Fix build break on arm32 for per-cpu sink patch
- Address comments on ETE dts bindings.
- Make ete_sysreg_read/write static (kernel test robot)
- Merged ete sysreg definition patch with ete support, to avoid
a "defined but unused warning" on build in part of the series.
- Add new bindings to MAINTAINERS
Changes since V3:
https://lore.kernel.org/linux-arm-kernel/1611737738-1493-1-git-send-email-anshuman.khandual@arm.com/
- ETE and TRBE changes have been captured in the respective patches
- Better support for nVHE
- Re-ordered and splitted the patches to keep the changes separate
for the generic/arm64 tree from CoreSight driver specific changes.
- Fixes for KVM handling of Trace/SPE
Changes since V2:
https://lore.kernel.org/linux-arm-kernel/1610511498-4058-1-git-send-email-anshuman.khandual@arm.com/
- Rebased on coresight/next
- Changed DT bindings for ETE
- Included additional patches for arm64 nvhe, perf aux buffer flags etc
- TRBE changes have been captured in the respective patches
Changes since V1:
https://lore.kernel.org/linux-arm-kernel/1608717823-18387-1-git-send-email-anshuman.khandual@arm.com/
- Converted both ETE and TRBE DT bindings into Yaml
- TRBE changes have been captured in the respective patches
Changes since RFC:
- There are not much ETE changes from Suzuki apart from splitting of the
ETE DTS patch
- TRBE changes have been captured in the respective patches
RFC:
https://lore.kernel.org/linux-arm-kernel/1605012309-24812-1-git-send-email-anshuman.khandual@arm.com/
Cc: Will Deacon <will at kernel.org>
Cc: Marc Zyngier <maz at kernel.org>
Cc: Peter Zilstra <peterz at infradead.org>
Cc: Mathieu Poirier <mathieu.poirier at linaro.org>
Cc: Suzuki K Poulose <suzuki.poulose at arm.com>
Cc: Mike Leach <mike.leach at linaro.org>
Cc: Linu Cherian <lcherian at marvell.com>
Cc: coresight at lists.linaro.org
Cc: linux-arm-kernel at lists.infradead.org
Cc: linux-kernel at vger.kernel.org
Anshuman Khandual (5):
arm64: Add TRBE definitions
coresight: core: Add support for dedicated percpu sinks
coresight: sink: Add TRBE driver
Documentation: coresight: trbe: Sysfs ABI description
Documentation: trace: Add documentation for TRBE
Suzuki K Poulose (14):
[Queued] kvm: arm64: Hide system instruction access to Trace registers
[Queued] kvm: arm64: Disable guest access to trace filter controls
perf: aux: Add flags for the buffer format
perf: aux: Add CoreSight PMU buffer formats
arm64: Add support for trace synchronization barrier
arm64: kvm: Enable access to TRBE support for host
coresight: etm4x: Move ETM to prohibited region for disable
coresight: etm-perf: Allow an event to use different sinks
coresight: Do not scan for graph if none is present
coresight: etm4x: Add support for PE OS lock
coresight: ete: Add support for ETE tracing
dts: bindings: Document device tree bindings for ETE
coresight: etm-perf: Handle stale output handles
dts: bindings: Document device tree bindings for Arm TRBE
.../testing/sysfs-bus-coresight-devices-trbe | 14 +
.../devicetree/bindings/arm/ete.yaml | 75 ++
.../devicetree/bindings/arm/trbe.yaml | 49 +
.../trace/coresight/coresight-trbe.rst | 38 +
MAINTAINERS | 2 +
arch/arm64/include/asm/barrier.h | 1 +
arch/arm64/include/asm/el2_setup.h | 13 +
arch/arm64/include/asm/kvm_arm.h | 3 +
arch/arm64/include/asm/kvm_host.h | 2 +
arch/arm64/include/asm/sysreg.h | 50 +
arch/arm64/kernel/cpufeature.c | 1 -
arch/arm64/kernel/hyp-stub.S | 3 +-
arch/arm64/kvm/debug.c | 6 +-
arch/arm64/kvm/hyp/nvhe/debug-sr.c | 42 +
arch/arm64/kvm/hyp/nvhe/switch.c | 1 +
drivers/hwtracing/coresight/Kconfig | 24 +-
drivers/hwtracing/coresight/Makefile | 1 +
drivers/hwtracing/coresight/coresight-core.c | 29 +-
.../hwtracing/coresight/coresight-etm-perf.c | 119 +-
.../coresight/coresight-etm4x-core.c | 161 ++-
.../coresight/coresight-etm4x-sysfs.c | 19 +-
drivers/hwtracing/coresight/coresight-etm4x.h | 83 +-
.../hwtracing/coresight/coresight-platform.c | 6 +
drivers/hwtracing/coresight/coresight-priv.h | 3 +
drivers/hwtracing/coresight/coresight-trbe.c | 1157 +++++++++++++++++
drivers/hwtracing/coresight/coresight-trbe.h | 152 +++
include/linux/coresight.h | 13 +
include/uapi/linux/perf_event.h | 13 +-
28 files changed, 2016 insertions(+), 64 deletions(-)
create mode 100644 Documentation/ABI/testing/sysfs-bus-coresight-devices-trbe
create mode 100644 Documentation/devicetree/bindings/arm/ete.yaml
create mode 100644 Documentation/devicetree/bindings/arm/trbe.yaml
create mode 100644 Documentation/trace/coresight/coresight-trbe.rst
create mode 100644 drivers/hwtracing/coresight/coresight-trbe.c
create mode 100644 drivers/hwtracing/coresight/coresight-trbe.h
--
2.24.1
More information about the linux-arm-kernel
mailing list