Since both sw_start and sw_end are master indices, the size of array
that holds them is sw_end - sw_start + 1, which the current code gets
wrong, allocating one item less than required.
This patch corrects the allocation size, avoiding potential slab
corruption.
Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>
[alexander.shishkin@linux.intel.com: re-wrote the commit message]
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently, the list of stm_sources linked to an stm device is protected by
a spinlock, which also means that sources' .unlink() method is called under
this spinlock. However, this method may (and does) sleep, which means
trouble.
This patch slightly reworks locking around stm::link_list so that bits that
might_sleep() are called with a mutex held instead. Modification of this
list requires both mutex and spinlock to be held, while looking at the list
can be done under either mutex or spinlock.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Right now, if stm device removal has to unbind from a policy (that is,
an stm device that has STP policy, gets removed), it will trigger a
nested lock on the stm device's policy mutex.
This patch fixes the problem by moving the locking from the policy
unbinding to policy removal (configfs path), where it's actually needed;
the other caller of the policy unbinding function already takes the
mutex around the call.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The newly added STM code uses SRCU, but does not ensure that
this code is part of the kernel:
drivers/built-in.o: In function `stm_source_link_show':
include/linux/srcu.h:221: undefined reference to `__srcu_read_lock'
include/linux/srcu.h:238: undefined reference to `__srcu_read_unlock'
drivers/built-in.o: In function `stm_source_link_drop':
include/linux/srcu.h:221: undefined reference to `__srcu_read_lock'
include/linux/srcu.h:238: undefined reference to `__srcu_read_unlock'
This adds a Kconfig 'select' statement like all the other SRCU using
drivers have.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 7bd1d4093c ("stm class: Introduce an abstraction for System Trace Module devices")
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If STM=n, it doesn't make sense to ask about STM_DUMMY and
STM_SOURCE_CONSOLE support, which are not even built when enabled
anyway. Hence hide these options if STM=n.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
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>
Pull SCSI target updates from Nicholas Bellinger:
"This series contains HCH's changes to absorb configfs attribute
->show() + ->store() function pointer usage from it's original
tree-wide consumers, into common configfs code.
It includes usb-gadget, target w/ drivers, netconsole and ocfs2
changes to realize the improved simplicity, that now renders the
original include/target/configfs_macros.h CPP magic for fabric drivers
and others, unnecessary and obsolete.
And with common code in place, new configfs attributes can be added
easier than ever before.
Note, there are further improvements in-flight from other folks for
v4.5 code in configfs land, plus number of target fixes for post -rc1
code"
In the meantime, a new user of the now-removed old configfs API came in
through the char/misc tree in commit 7bd1d4093c ("stm class: Introduce
an abstraction for System Trace Module devices").
This merge resolution comes from Alexander Shishkin, who updated his stm
class tracing abstraction to account for the removal of the old
show_attribute and store_attribute methods in commit 517982229f
("configfs: remove old API") from this pull. As Alexander says about
that patch:
"There's no need to keep an extra wrapper structure per item and the
awkward show_attribute/store_attribute item ops are no longer needed.
This patch converts policy code to the new api, all the while making
the code quite a bit smaller and easier on the eyes.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>"
That patch was folded into the merge so that the tree should be fully
bisectable.
* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (23 commits)
configfs: remove old API
ocfs2/cluster: use per-attribute show and store methods
ocfs2/cluster: move locking into attribute store methods
netconsole: use per-attribute show and store methods
target: use per-attribute show and store methods
spear13xx_pcie_gadget: use per-attribute show and store methods
dlm: use per-attribute show and store methods
usb-gadget/f_serial: use per-attribute show and store methods
usb-gadget/f_phonet: use per-attribute show and store methods
usb-gadget/f_obex: use per-attribute show and store methods
usb-gadget/f_uac2: use per-attribute show and store methods
usb-gadget/f_uac1: use per-attribute show and store methods
usb-gadget/f_mass_storage: use per-attribute show and store methods
usb-gadget/f_sourcesink: use per-attribute show and store methods
usb-gadget/f_printer: use per-attribute show and store methods
usb-gadget/f_midi: use per-attribute show and store methods
usb-gadget/f_loopback: use per-attribute show and store methods
usb-gadget/ether: use per-attribute show and store methods
usb-gadget/f_acm: use per-attribute show and store methods
usb-gadget/f_hid: use per-attribute show and store methods
...
devm_ioremap() returns NULL on error, it doesn't return an ERR_PTR,
which is what the current code does. This patch corrects these
checks.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
STM policy handling is basically configfs, I honestly don't know how we
ended up without a Kconfig dependency, but thanks to randconfig testing,
it's now caught.
Reported-by: Jim Davis <jim.epost@gmail.com>
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use unsigned long in place of size_t to operate on buffer sizes and
offsets to clean up the 32 bit build.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Source device's link is protected with srcu, mark it as such to have
proper build-time validation of accesses to this field. The update
side that's dereferencing it under an update lock also needs an
accessor to dereference this field to keep sparse happy.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
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>
Parallel Trace Interface (PTI) unit is a trace output device that sends
data over a PTI port.
The driver provides interfaces to configure bus width, bus clock divider
and mode. Tracing is enabled via output device's "active" attribute.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Memory Storage Unit (MSU) is a trace output device that collects trace
data to system memory. It consists of 2 independent Memory Storage
Controllers (MSCs).
This driver provides userspace interfaces to configure in-memory tracing
parameters, such as contiguous (high-order allocation) buffer or multiblock
(scatter list) buffer mode, wrapping (data overwrite) and number and sizes
of windows in multiblock mode. Userspace can read the buffers via mmap()ing
or read()ing of the corresponding device node.
Signed-off-by: Laurent Fert <laurent.fert@intel.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Software Trace Hub (STH) is a trace source device in the Intel TH
architecture, it generates data that then goes through the switch into
one or several output ports.
STH collects data from software sources using the stm device class
abstraction.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Global Trace Hub (GTH) is the central component of Intel TH architecture;
it carries out switching between the trace sources and trace outputs, can
enable/disable tracing, perform STP encoding, internal buffering, control
backpressure from outputs to sources and so on.
This property is also reflected in the software model; GTH (switch) driver
is required for the other subdevices to probe, because it matches trace
output devices against its output ports and configures them accordingly.
It also implements an interface for output ports to request trace enabling
or disabling and a few other useful things.
For userspace, it provides an attribute group "masters", which allows
configuration of per-master trace output destinations for up to master 255
and "256+" meaning "masters 256 and above". It also provides an attribute
group to discover and configure some of the parameters of its output ports,
called "outputs". Via these the user can set up data retention policy for
an individual output port or check if it is in reset state.
Signed-off-by: Laurent Fert <laurent.fert@intel.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This patch adds basic support for PCI-based Intel TH devices. It requests
2 bars (configuration registers for the subdevices and STH channel MMIO
region) and calls into Intel TH core code to create the bus with subdevices
etc.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Intel(R) Trace Hub (TH) is a set of hardware blocks (subdevices) that
produce, switch and output trace data from multiple hardware and
software sources over several types of trace output ports encoded
in System Trace Protocol (MIPI STPv2) and is intended to perform
full system debugging.
For these subdevices, we create a bus, where they can be discovered
and configured by userspace software.
This patch creates this bus infrastructure, three types of devices
(source, output, switch), resource allocation, some callback mechanisms
to facilitate communication between the subdevices' drivers and some
common sysfs attributes.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This is a simple stm_source class device driver (kernelspace stm trace
source) that registers a console and sends kernel messages over STM
devices.
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This is a simple module that pretends to be an stm device and discards
all the data that comes in. Useful for testing stm class and its users.
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A System Trace Module (STM) is a device exporting data in System Trace
Protocol (STP) format as defined by MIPI STP standards. Examples of such
devices are Intel(R) Trace Hub and Coresight STM.
This abstraction provides a unified interface for software trace sources
to send their data over an STM device to a debug host. In order to do
that, such a trace source needs to be assigned a pair of master/channel
identifiers that all the data from this source will be tagged with. The
STP decoder on the debug host side will use these master/channel tags to
distinguish different trace streams from one another inside one STP
stream.
This abstraction provides a configfs-based policy management mechanism
for dynamic allocation of these master/channel pairs based on trace
source-supplied string identifier. It has the flexibility of being
defined at runtime and at the same time (provided that the policy
definition is aligned with the decoding end) consistency.
For userspace trace sources, this abstraction provides write()-based and
mmap()-based (if the underlying stm device allows this) output mechanism.
For kernel-side trace sources, we provide "stm_source" device class that
can be connected to an stm device at run time.
Cc: linux-api@vger.kernel.org
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
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>
