TraceID values have to be unique for all tracers and
consistent between drivers and user space. As such
introducing a central function to be used whenever a
traceID value is required.
The patch also account for data traceIDs, which are usually
I(N) + 1.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg 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: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Adding an ETB10 specific AUX area operations to be used
by the perf framework when events are initialised.
Part of this operation involves modeling the mmap'ed area
based on the specific ways a sink buffer gathers information.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Adding an operation mode to the sink->enable() API in order
to prevent simultaneous access from different callers.
TPIU and TMC won't be supplemented with the AUX area
API immediately and as such ignore the new mode.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Moving to use local atomic operations to take advantage of the
lockless implementation, something that will come handy when
the ETB is accessed from the Perf subsystem. Also changing the
name of the variable to something more meaningful.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
That way traces can be enabled and disabled automatically
from the Perf subystem using the PMU abstraction.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Adding new mode to limit tracing to kernel or user space.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is really no point in having two functions to take care
of doing the initial tracer configuration. As such moving
everything to 'etm_set_default()'.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Changing default configuration to include the entire address
range rather than just the kernel. That way traces are more
inclusive and it is easier to narrow down if needed.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is no need to use the event enable's "always false" event to
stop trace collection. For that purpose setting the programming bit
(ETMCR:10) is enough.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Adding a new mode to source API enable() in order to
distinguish where the request comes from. That way it is
possible to perform different operations based on where
the request was issued from.
The ETM4x driver is also modified to keep in sync with the
new interface.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Splitting "etm_drvdata" in two sections, one for the HW specific
data and another for user configuration.
That way it is easier to manipulate and zero out the configuration
data when more than one concurrent tracing session configuration
is active.
Also taking care of up-lifting all the code affected by this new
arrangement. No loss or gain of functionality (other than what is
mentioned above) is introduced by this patch.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Calling function 'smp_call_function_single()' to unlock a
tracer and calling it again right after to perform the
default initialisation doesn't make sense.
Moving 'etm_os_unlock()' just before making the default
initialisation results in the same outcome while saving
one call to 'smp_call_function_single()'.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg 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: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Moving functions etm_readl/writel to file "coresight-etm.h"
so that the main ETM3x driver can be split in more than one
file.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Moving PM runtime operations in Coresight devices enable() and
disable() API to the framework core when a path is setup. That
way the runtime core doesn't have to be involved everytime a
path is enabled. It also avoids calling runtime PM operations
in IRQ context.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add an API allowing external code to quickly get a handle on the
sink within a path. The sink is always last, but adding an API allows
to keep the path's node structure private and remove redundant checks.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When using the Coresight framework from the sysFS interface a
tracer is always handling a single session and as such, a path
can be associated with a tracer. But when supporting multiple
session per tracer there is no guarantee that sessions will always
have the same path from source to sink.
This patch is removing the automatic association between path and
tracers. The building of a path and enablement of the components
in the path are decoupled, allowing for the association of a path
with a session rather than a tracer.
To keep backward functionality with the current sysFS access methods
a per-cpu place holder is used to keep a handle on the path built when
tracers are enabled. Lastly APIs to build paths and enable tracers are
made public so that other subsystem can interact with the Coresight
framework.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The dma_alloc_coherent return an "void *" not an "void __iomen *".
It uses the wrong parameters when calls dma_free_coherent function.
The sparse tool output logs as the following:
coresight-tmc.c:199:23: expected void *<noident>
coresight-tmc.c:199:23: got void [noderef] <asn:2>*vaddr
coresight-tmc.c:336:30: warning: incorrect type in assignment
(different address spaces)
coresight-tmc.c:336:30: expected char *buf
coresight-tmc.c:336:30: got void [noderef] <asn:2>*
coresight-tmc.c:769:50: warning: incorrect type in argument 4
(different base types)
coresight-tmc.c:769:50: expected unsigned long long
[unsigned] [usertype] dma_handle
coresight-tmc.c:769:50: got restricted gfp_t
Signed-off-by: Eric Long <eric.long@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
"DEVICE_ATTR_RO(name)" should be defined as static. And
there is an unnecessary space at the front of the code.
The sparse tool output logs as the following:
coresight-etm4x.c:2224:1: warning: symbol 'dev_attr_trcoslsr' was
not declared. Should it be static?
coresight-etm4x.c:2225:1: warning: symbol 'dev_attr_trcpdcr' was
not declared. Should it be static?
coresight-etm4x.c:2226:1: warning: symbol 'dev_attr_trcpdsr' was
not declared. Should it be static?
And the smatch tool output logs as the following:
of_coresight.c:89 of_coresight_alloc_memory() warn:
inconsistent indenting
Signed-off-by: Eric Long <eric.long@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Other than plainly parsing the device tree there is no way to
know which CPU a tracer is affined to. As such adding an
interface to lookup the CPU field enclosed in the etm_drvdata
structure that was initialised at boot time.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The coresight drivers have absolutely no control over bind and unbind
operations triggered from sysfs. The operations simply can't be
cancelled or denied event when one or several tracing sessions are
under way. Since the memory associated to individual device is
invariably freed, the end result is a kernel crash when the path from
source to sink is travelled again as demonstrated here[1].
One solution could be to keep track of all the path (i.e tracing
session) that get created and iterate through the elements of those path
looking for the coresight device that is being removed. This proposition
doesn't scale well since there is no upper bound on the amount of
concurrent trace session that can be created.
With the above in mind, this patch prevent devices from being unbounded
from their driver by using the driver->suppress_bind_attr option. That way
trace sessions can be managed without fearing to loose devices.
Since device can't be removed anymore the xyz_remove() functions found in
each driver is also removed.
[1]. http://www.spinics.net/lists/arm-kernel/msg474952.html
Reported-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In function 'coresight_unregister()', all references to the csdev that
is being taken away need to be removed from the topology. Otherwise
building the next coresight path from source to sink may use memory
that has been released.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The reference count taken by function bus_find_device() needs
to be released if a child device is found, something this patch
is adding.
Reported-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In its current form the code never frees csdev->refcnt allocated
in coresight_register(). There is also a problem with csdev->conns
that is freed before device_unregister() rather than in the device
release function.
This patch addresses both issues by moving kfree(csdev->conns) to
coresight_device_release() and freeing csdev->refcnt, also in
the same function.
Reported-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew F. Davis <afd@ti.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Connection child names associated to ports can sometimes be NULL,
which is the case when booting a system on QEMU or when the Coresight
power domain isn't switched on.
This patch is adding a check to make sure a NULL string isn't fed
to strcmp(), something that avoid crashing the system.
Cc: <stable@vger.kernel.org> # v3.18+
Reported-by: Tyler Baker <tyler.baker@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
By adding the function name at the beginning of the error
message there is no doubt as to where the failing condition
occurred.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
SysFS rules stipulate that only one value can be conveyed per
file. As such splitting the "status" interface in individual files.
This is also useful for user space applications - that way they can
probe each file individually rather than having to parse a list of entries.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Without access to the device tree, it is impossible to know
what CPU a tracer is affined to. As such adding a new sysFS
interface to convey the information.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add comment to function coresight_enable_path() to make
sure there is no misunderstanding about what the code does.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1. TRCRSCTLRn - Resource Selection Control Registers n=0~1 are reserved,
we shouldn't access them.
2. The max number of 'n' here is defined in TRCIDR4.NUMRSPAIR whoes value
indicates the number of resource selection *pairs*, and 0 indicates
one resource selection pair, 1 indicates two pairs, and so on ...
So, the total number of resource selection control registers which we can
access is (TRCIDR4.NUMRSPAIR * 2)
Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Like ETTv3, ETMv4 also needs the similar modifications to support Context
ID tracing when PID namespace is enabled.
Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The Coresight ETM drivers already support context-ID tracing, but it won't
work when PID namespace is enabled. This is because when using PID
namespace a process id (ie. VPID) seen from the current namespace differs
from the id (ie. PID) seen by kernel.
So when users write the process id seen by themselves to ETM, there needs
to be a translation from VPID to PID, as such ETM drivers will write the
PID into the Context ID register correctly.
Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
'ctxid_val' array was used to store the value of ETM context ID comparator
which actually stores the process ID to be traced, so using 'ctxid_pid' as
its name instead make it easier to understand.
This patch also changes the ABI, it is normally not allowed, but
fortunately it is a testing ABI and very new for now. Nevertheless,
if you don't think it should be changed, we could always add an alias
for userspace.
Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
'ctxid_val' array was used to store the value of ETM context ID comparator
which actually stores the process ID to be traced, so using 'ctxid_pid' as
its name instead make it easier to understand.
This patch also changes the ABI, it is normally not allowed, but
fortunately it is a testing ABI and very new for now. Nevertheless,
if you don't think it should be changed, we could always add an alias
for userspace.
Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Macro builtin_platform_driver can be used for builtin drivers
that don't do anything in driver init. This file depends on
Kconfig CONFIG_CORESIGHT_LINKS_AND_SINKS which eventually
depends on CORESIGHT. Both CONFIG_CORESIGHT_LINKS_AND_SINKS and
CORESIGHT are bool. So, use builtin_platform_driver and remove
some boilerplate code.
Also, remove header file init.h as functionality like module_init
and module_exit is now relocated to module.h.
Signed-off-by: Vaishali Thakkar <vthakkar1994@gmail.com>
Suggested-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add Qualcomm's PTM v1.1 peripheral ID to supported devices.
This device could be found at least in MSM8974 and APQ8064
chipsets.
Signed-off-by: Ivan T. Ivanov <ivan.ivanov@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In commit 2e1cdfe184 ("coresight-etm4x:
Adding CoreSight ETM4x driver") this driver was added.
It uses module_amba_driver() to register itself with the system,
which is just an alias for module_driver. This currently works by
relying on getting that via init.h but we are planning to move that
code[1] to module.h -- at which time this will fail to compile since
it does not include module.h currently, resulting in:
drivers/hwtracing/coresight/coresight-etm4x.c:2701:1: note: in expansion of macro ‘module_amba_driver’
module_amba_driver(etm4x_driver);
^
include/linux/device.h:1296:1: error: type defaults to ‘int’ in declaration of ‘module_init’ [-Werror=implicit-int]
module_init(__driver##_init); \
^
In the future, the amba support may want to create another alias that
uses builtin_driver[2] for cases like this which are using bool Kconfig
triggers, but for now we just fix the implicit include.
[1] https://lkml.kernel.org/r/1433276168-21550-1-git-send-email-paul.gortmaker@windriver.com
[2] https://lkml.kernel.org/r/1431287385-1526-1-git-send-email-paul.gortmaker@windriver.com
Cc: Pratik Patel <pratikp@codeaurora.org>
Cc: Kaixu Xia <xiakaixu@huawei.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In commit 620cf787c1 ("coresight: replicator:
Add Qualcomm CoreSight Replicator driver") this driver was added.
It uses module_amba_driver(replicator_driver) to register itself with
the system -- which is just an alias for module_driver. This currently
works by relying on getting that via init.h but we are planning to move
that code[1] to module.h -- at which time this will fail to compile since
it does not include module.h currently, resulting in:
drivers/hwtracing/coresight/coresight-replicator-qcom.c:214:1: error: type defaults to 'int' in declaration of 'module_init' [-Werror=implicit-int]
drivers/hwtracing/coresight/coresight-replicator-qcom.c:214:1: error: type defaults to 'int' in declaration of 'module_exit' [-Werror=implicit-int]
In the future, the amba support may want to create another alias that
uses builtin_driver[2] for cases like this which are using bool Kconfig
triggers, but for now we just fix the implicit include.
[1] https://lkml.kernel.org/r/1433276168-21550-1-git-send-email-paul.gortmaker@windriver.com
[2] https://lkml.kernel.org/r/1431287385-1526-1-git-send-email-paul.gortmaker@windriver.com
Cc: Pratik Patel <pratikp@codeaurora.org>
Cc: Ivan T. Ivanov <ivan.ivanov@linaro.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg 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: Pratik Patel <pratikp@codeaurora.org>
Signed-off-by: Ivan T. Ivanov <ivan.ivanov@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
As can be seen from the datasheet of the CoreSight
Components, DDI0314 table A-4 the funnel has a clock signal
apart from the AHB interconnect ("amba_pclk", that we're
already handling) called ATCLK, ARM Trace Clock, that SoC
implementers may provide from an entirely different clock
source. So to model this correctly create an optional
path for handling ATCLK alongside the PCLK so we don't
break old platforms that only define PCLK ("amba_pclk") but
still makes it possible for SoCs that have both clock signals
(such as the DB8500) to fetch and prepare/enable/disable/
unprepare both clocks.
The ATCLK is enabled and disabled using the runtime PM
callbacks. As the replicator is a platform device, the
code is a bit different from the other CoreSight components
and the bus core does not activate runtime PM by default,
so we need a few extra calls.
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
As can be seen from the datasheet of the CoreSight
Components, DDI0314 table A-6 the funnel has a clock signal
apart from the AHB interconnect ("amba_pclk", that we're
already handling) called ATCLK, ARM Trace Clock, that SoC
implementers may provide from an entirely different clock
source. So to model this correctly create an optional
path for handling ATCLK alongside the PCLK so we don't
break old platforms that only define PCLK ("amba_pclk") but
still makes it possible for SoCs that have both clock signals
(such as the DB8500) to fetch and prepare/enable/disable/
unprepare both clocks.
The ATCLK is enabled and disabled using the runtime PM
callbacks.
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
As can be seen from the datasheet of the CoreSight
Components, DDI0314 table A-8 the ETB has a clock signal
apart from the AHB interconnect ("amba_pclk", that we're
already handling) called ATCLK, ARM Trace Clock, that SoC
implementers may provide from an entirely different clock
source. So to model this correctly create an optional
path for handling ATCLK alongside the PCLK so we don't
break old platforms that only define PCLK ("amba_pclk") but
still makes it possible for SoCs that have both clock signals
(such as the DB8500) to fetch and prepare/enable/disable/
unprepare both clocks.
The ATCLK is enabled and disabled using the runtime PM
callbacks.
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
As can be seen from the datasheet of the CoreSight
Components, DDI0314H page A-19 the TPIU has a clock signal
apart from the AHB interconnect ("amba_pclk", that we're
already handling) called ATCLK, ARM Trace Clock, that SoC
implementers may provide from an entirely different clock
source. So to model this correctly create an optional
path for handling ATCLK alongside the PCLK so we don't
break old platforms that only define PCLK ("amba_pclk") but
still makes it possible for SoCs that have both clock signals
(such as the DB8500) to fetch and prepare/enable/disable/
unprepare both clocks in conjunction.
The ATCLK is enabled and disabled using the runtime PM
callbacks.
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
As can be seen from the datasheet of the CoreSight
Components, DDI0401C A.1.1 the ETM has a clock signal
apart from the AHB interconnect ("amba_pclk", that we're
already handling) called ATCLK, ARM Trace Clock, that SoC
implementers may provide from an entirely different clock
source. So to model this correctly create an optional
path for handling ATCLK alongside the PCLK so we don't
break old platforms that only define PCLK ("amba_pclk") but
still makes it possible for SoCs that have both clock signals
(such as the DB8500) to fetch and prepare/enable/disable/
unprepare both clocks.
The ATCLK is enabled and disabled using the runtime PM
callbacks.
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This uses runtime PM to manage the PCLK ("amba_pclk") instead
of screwing around with the framework by going in and taking
a copy from the amba device. The amba bus core will unprepare
and disable the clock when the device is unused when
CONFIG_PM is selected, else the clock will be always on.
Prior to this patch, as the AMBA primecell bus code enables
the PCLK, it would be left on after probe as
the clk_prepare_enable() and clk_disable_unprepare() was
called and thus just increase and decreas the refcount by
one, without it reaching zero and actually disabling the
clock. Now the runtime PM callbacks will make sure the PCLK
is properly disabled after probe.
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
