Coresight includes debug module and usually the module connects with CPU
debug logic. ARMv8 architecture reference manual (ARM DDI 0487A.k) has
description for related info in "Part H: External Debug".

Chapter H7 "The Sample-based Profiling Extension" introduces several
sampling registers, e.g. we can check program counter value with
combined CPU exception level, secure state, etc. So this is helpful for
analysis CPU lockup scenarios, e.g. if one CPU has run into infinite
loop with IRQ disabled. In this case the CPU cannot switch context and
handle any interrupt (including IPIs), as the result it cannot handle
SMP call for stack dump.

This patch is to enable coresight debug module, so firstly this driver
is to bind apb clock for debug module and this is to ensure the debug
module can be accessed from program or external debugger. And the driver
uses sample-based registers for debug purpose, e.g. when system triggers
panic, the driver will dump program counter and combined context
registers (EDCIDSR, EDVIDSR); by parsing context registers so can
quickly get to know CPU secure state, exception level, etc.

Some of the debug module registers are located in CPU power domain, so
this requires the CPU power domain stays on when access related debug
registers, but the power management for CPU power domain is quite
dependent on SoC integration for power management. For the platforms
which with sane power controller implementations, this driver follows
the method to set EDPRCR to try to pull the CPU out of low power state
and then set 'no power down request' bit so the CPU has no chance to
lose power.

If the SoC has not followed up this design well for power management
controller, the user should use the command line parameter or sysfs
to constrain all or partial idle states to ensure the CPU power
domain is enabled and access coresight CPU debug component safely.
Signed-off-by: NLeo Yan <leo.yan@linaro.org>
Reviewed-by: NSuzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The TMC block can operate in 3 modes (ETB, ETF and ETR) and accessed
via two interfaces (sysFS and Perf).  That makes 6 mode to cover, which
is way too much coupling for a single file.

This patch splits the original TMC driver in 2 halves, one for ETB/ETF
and another one for ETR mode.  A common core is kept for functionality
common to all 3 modes.
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: NSuzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This driver adds support for the STM CoreSight IP block, allowing any
system compoment (HW or SW) to log and aggregate messages via a
single entity.

The CoreSight STM exposes an application defined number of channels
called stimulus port.  Configuration is done using entries in sysfs
and channels made available to userspace via configfs.
Signed-off-by: NPratik Patel <pratikp@codeaurora.org>
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: NMichael Williams <michael.williams@arm.com>
Signed-off-by: NChunyan Zhang <zhang.chunyan@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Adding a set of API allowing the Perf core to treat ETMv4
tracers like other PMUs.
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

As with the etm3x driver, sysFS entries are big enough to justify
their own file. As such moving all sysFS related declarations to
a dedicated location.

No gain/loss of functionality is incurred from this patch.
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Perf is a well known and used tool for performance monitoring
and much more. A such it is an ideal candidate for integration
with coresight based HW tracing.

This patch introduces a PMU that represent a coresight tracer to
the Perf core.

Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

SysFS entries are big enough to justify their own file.
As such moving all sysFS related declarations to a dedicated
location.
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This driver manages Qualcomm CoreSight Replicator device, which
resides on the AMBA bus. Replicator has been made programmable to
allow software to turn of the replicator branch to sink that is not
being used. This avoids trace traffic to the unused/non-current sink
from causing back pressure that results in overflows at the source.
Signed-off-by: NPratik Patel <pratikp@codeaurora.org>
Signed-off-by: NIvan T. Ivanov <ivan.ivanov@linaro.org>
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This driver manages the CoreSight ETMv4 (Embedded Trace Macrocell) IP block
to support HW assisted tracing on ARMv7 and ARMv8 architectures.
Signed-off-by: NPratik Patel <pratikp@codeaurora.org>
Signed-off-by: NKaixu Xia <xiakaixu@huawei.com>
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Keeping drivers related to HW tracing on ARM, i.e coresight,
under "drivers/coresight" doesn't make sense when other
architectures start rolling out technologies of the same
nature.

As such creating a new "drivers/hwtracing" directory where all
drivers of the same kind can reside, reducing namespace
pollution under "drivers/".
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This driver manages CoreSight ETM (Embedded Trace Macrocell) that
supports processor tracing. Currently supported version are ARM
ETMv3.x and PTM1.x.
Signed-off-by: NPratik Patel <pratikp@codeaurora.org>
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>

coresight-etm3x: adding missing error checking
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This driver manages non-configurable CoreSight Replicator that
takes a single input trace data stream and replicates it to
produce two identical trace data output streams. Replicators
are typically used to route single interleaved trace data
stream to two or more sinks.
Signed-off-by: NPratik Patel <pratikp@codeaurora.org>
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This driver manages CoreSight Funnel which acts as a link.
Funnels have multiple input ports (typically 8) each of which
represents an input trace data stream. These multiple input trace
data streams are interleaved into a single output stream coming
out of the Funnel.
Signed-off-by: NPratik Patel <pratikp@codeaurora.org>
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This driver manages CoreSight ETB (Embedded Trace Buffer) which
acts as a circular buffer sink collecting generated trace data.
Signed-off-by: NPratik Patel <pratikp@codeaurora.org>
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This driver manages CoreSight TPIU (Trace Port Interface Unit)
which acts as a sink. TPIU is typically connected to some offchip
hardware hosting a storage buffer.
Signed-off-by: NPratik Patel <pratikp@codeaurora.org>
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This driver manages CoreSight TMC (Trace Memory Controller) which
can act as a link or a sink depending upon its configuration. It
can present itself as an ETF (Embedded Trace FIFO) or ETR
(Embedded Trace Router).

ETF when configured in circular buffer mode acts as a trace
collection sink. When configured in HW fifo mode it acts as link.
ETR always acts as a sink and can be used to route data to memory
allocated in RAM.
Signed-off-by: NPratik Patel <pratikp@codeaurora.org>
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

CoreSight components are compliant with the ARM CoreSight
architecture specification and can be connected in various
topologies to suit a particular SoC tracing needs. These trace
components can generally be classified as sources, links and
sinks. Trace data produced by one or more sources flows through
the intermediate links connecting the source to the currently
selected sink.

The CoreSight framework provides an interface for the CoreSight trace
drivers to register themselves with. It's intended to build up a
topological view of the CoreSight components and configure the
correct serie of components on user input via sysfs.

For eg., when enabling a source, the framework builds up a path
consisting of all the components connecting the source to the
currently selected sink(s) and enables all of them.

The framework also supports switching between available sinks
and provides status information to user space applications
through the debugfs interface.
Signed-off-by: NPratik Patel <pratikp@codeaurora.org>
Signed-off-by: NMathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>