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path: root/drivers/hwtracing/coresight/coresight-tpiu.c
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2021-02-05Merge branch 'devel-stable' of git://git.armlinux.org.uk/~rmk/linux-arm into ↵Greg Kroah-Hartman
char-misc-next This merges from linux-arm at 860660fd829e ("ARM: 9055/1: mailbox: arm_mhuv2: make remove callback return void") into char-misc-next to get the amba fixes from Uwe. Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Cc: Russell King <linux@armlinux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-04coresight: Convert coresight_timeout to use access abstractionSuzuki K Poulose
Convert the generic routines to use the new access abstraction layer gradually, starting with coresigth_timeout. Link: https://lore.kernel.org/r/20210110224850.1880240-6-suzuki.poulose@arm.com Cc: Mike Leach <mike.leach@linaro.org> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Link: https://lore.kernel.org/r/20210201181351.1475223-8-mathieu.poirier@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-04coresight: tpiu: Prepare for using coresight device access abstractionSuzuki K Poulose
Prepare the TPIU driver to make use of the CoreSight device access abstraction layer. The driver touches the device even before the coresight device is registered. Thus we could be accessing the devices without a csdev. As we are about to use the abstraction layer for accessing the device, pass in the access directly to avoid having to deal with the un-initialised csdev. Link: https://lore.kernel.org/r/20210110224850.1880240-5-suzuki.poulose@arm.com Cc: Mike Leach <mike.leach@linaro.org> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Link: https://lore.kernel.org/r/20210201181351.1475223-7-mathieu.poirier@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-04coresight: Introduce device access abstractionSuzuki K Poulose
We are about to introduce support for sysreg access to ETMv4.4+ component. Since there are generic routines that access the registers (e.g, CS_LOCK/UNLOCK , claim/disclaim operations, timeout) and in order to preserve the logic of these operations at a single place we introduce an abstraction layer for the accesses to a given device. Link: https://lore.kernel.org/r/20210110224850.1880240-4-suzuki.poulose@arm.com Cc: Mike Leach <mike.leach@linaro.org> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Link: https://lore.kernel.org/r/20210201181351.1475223-6-mathieu.poirier@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-02-02amba: Make the remove callback return voidUwe Kleine-König
All amba drivers return 0 in their remove callback. Together with the driver core ignoring the return value anyhow, it doesn't make sense to return a value here. Change the remove prototype to return void, which makes it explicit that returning an error value doesn't work as expected. This simplifies changing the core remove callback to return void, too. Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com> Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Acked-by: Krzysztof Kozlowski <krzk@kernel.org> # for drivers/memory Acked-by: Mark Brown <broonie@kernel.org> Acked-by: Linus Walleij <linus.walleij@linaro.org> Acked-by: Suzuki K Poulose <suzuki.poulose@arm.com> # for hwtracing/coresight Acked-By: Vinod Koul <vkoul@kernel.org> # for dmaengine Acked-by: Guenter Roeck <linux@roeck-us.net> # for watchdog Acked-by: Wolfram Sang <wsa@kernel.org> # for I2C Acked-by: Takashi Iwai <tiwai@suse.de> # for sound Acked-by: Vladimir Zapolskiy <vz@mleia.com> # for memory/pl172 Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/20210126165835.687514-5-u.kleine-koenig@pengutronix.de Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
2020-12-08coresight: remove broken __exit annotationsArnd Bergmann
Functions that are annotated __exit are discarded for built-in drivers, but the .remove callback in a device driver must still be kept around to allow bind/unbind operations. There is now a linker warning for the discarded symbol references: `tmc_remove' referenced in section `.data' of drivers/hwtracing/coresight/coresight-tmc-core.o: defined in discarded section `.exit.text' of drivers/hwtracing/coresight/coresight-tmc-core.o `tpiu_remove' referenced in section `.data' of drivers/hwtracing/coresight/coresight-tpiu.o: defined in discarded section `.exit.text' of drivers/hwtracing/coresight/coresight-tpiu.o `etb_remove' referenced in section `.data' of drivers/hwtracing/coresight/coresight-etb10.o: defined in discarded section `.exit.text' of drivers/hwtracing/coresight/coresight-etb10.o `static_funnel_remove' referenced in section `.data' of drivers/hwtracing/coresight/coresight-funnel.o: defined in discarded section `.exit.text' of drivers/hwtracing/coresight/coresight-funnel.o `dynamic_funnel_remove' referenced in section `.data' of drivers/hwtracing/coresight/coresight-funnel.o: defined in discarded section `.exit.text' of drivers/hwtracing/coresight/coresight-funnel.o `static_replicator_remove' referenced in section `.data' of drivers/hwtracing/coresight/coresight-replicator.o: defined in discarded section `.exit.text' of drivers/hwtracing/coresight/coresight-replicator.o `dynamic_replicator_remove' referenced in section `.data' of drivers/hwtracing/coresight/coresight-replicator.o: defined in discarded section `.exit.text' of drivers/hwtracing/coresight/coresight-replicator.o `catu_remove' referenced in section `.data' of drivers/hwtracing/coresight/coresight-catu.o: defined in discarded section `.exit.text' of drivers/hwtracing/coresight/coresight-catu.o Remove all those annotations. Fixes: 8b0cf82677d1 ("coresight: stm: Allow to build coresight-stm as a module") Reviewed-by: Stephen Boyd <swboyd@chromium.org> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Link: https://lore.kernel.org/r/20201208182651.1597945-3-mathieu.poirier@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-11-27coresight-tpiu: Fix W=1 warning in TPIU driverMathieu Poirier
CC drivers/hwtracing/coresight/coresight-etm4x-core.o CC drivers/hwtracing/coresight/coresight-etm4x-sysfs.o CC drivers/hwtracing/coresight/coresight-stm.o drivers/hwtracing/coresight/coresight-tpiu.c:53: warning: Cannot understand * @base: memory mapped base address for this component. on line 53 - I thought it was a doc line CC drivers/hwtracing/coresight/coresight-cpu-debug.o CC drivers/hwtracing/coresight/coresight-catu.o Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Link: https://lore.kernel.org/r/20201127175256.1092685-15-mathieu.poirier@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-28coresight: tpiu: Allow tpiu to be built as a moduleKim Phillips
Allow to build coresight-tpiu as a module, for ease of development. - Kconfig becomes a tristate, to allow =m - add a tpiu_remove function, for module unload - add a MODULE_DEVICE_TABLE for autoloading on boot Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Cc: Leo Yan <leo.yan@linaro.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Suzuki K Poulose <Suzuki.Poulose@arm.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Russell King <linux@armlinux.org.uk> Reviewed-by: Mike Leach <mike.leach@linaro.org> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Kim Phillips <kim.phillips@arm.com> Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Link: https://lore.kernel.org/r/20200928163513.70169-13-mathieu.poirier@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-20coresight: Use platform agnostic namesSuzuki K Poulose
So far we have reused the name of the "platform" device for the CoreSight device. But this is not very intuitive when we move to ACPI. Also, the ACPI device names have ":" in them (e.g, ARMHC97C:01), which the perf tool doesn't like very much. This patch introduces a generic naming scheme, givin more intuitive names for the devices that appear on the CoreSight bus. The names follow the pattern "prefix" followed by "index" (e.g, etm5). We maintain a list of allocated devices per "prefix" to make sure we don't allocate a new name when it is reprobed (e.g, due to unsatisifed device dependencies). So, we maintain the list of "fwnodes" of the parent devices to allocate a consistent name. All devices except the ETMs get an index allocated in the order of probing. ETMs get an index based on the CPU they are attached to. TMC devices are named using "tmc_etf", "tmc_etb", and "tmc_etr" prefixes depending on the configuration of the device. The replicators and funnels are not classified as dynamic/static anymore. One could easily figure that out by checking the presence of "mgmt" registers under sysfs. Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-20coresight: Rearrange platform data probingSuzuki K Poulose
We are about to introduce methods to clean up the platform data as we switch to tracking the device reference from "name" to "fwnode handles" for device connections. This requires us to drop the fwnode handle references when the data is no longer required - i.e, when the device probe fails or the device gets unregistered. In order to consolidate the invocation of the cleanup, we delay the platform probing to the very last minute, possibly before invoking the coresight_register. Then, we leave the coresight core code to do the clean up. i.e, if the coresight_register fails, it takes care of freeing the data. Otherwise, coresight_unregister will do the necessary operations. Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-20coresight: Remove name from platform descriptionSuzuki K Poulose
We are about to use a name independent of the parent AMBA device name. As such, there is no need to have it in the platform description. Let us move this to coresight description instead. Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-20coresight: Introduce generic platform data helperSuzuki K Poulose
So far we have hard coded the DT platform parsing code in every driver. Introduce generic helper to parse the information provided by the firmware in a platform agnostic manner, in preparation for the ACPI support. Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19coresight: tpiu: Clean up device specific dataSuzuki K Poulose
Switch to using the coresight device instead of the parent amba device. Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-25coresight: Move reference counting inside sink driversMathieu Poirier
When operating in CPU-wide mode with an N:1 source/sink HW topology, multiple CPUs can access a sink concurrently. As such reference counting needs to happen when the device's spinlock is held to avoid racing with other operations (start(), update(), stop()), such as: session A Session B ----- ------- enable_sink atomic_inc(refcount) = 1 ... atomic_dec(refcount) = 0 enable_sink if (refcount == 0) disable_sink atomic_inc() Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Tested-by: Leo Yan <leo.yan@linaro.org> Tested-by: Robert Walker <robert.walker@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-25coresight: Adding return code to sink::disable() operationMathieu Poirier
In preparation to handle device reference counting inside of the sink drivers, add a return code to the sink::disable() operation so that proper action can be taken if a sink has not been disabled. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Tested-by: Leo Yan <leo.yan@linaro.org> Tested-by: Robert Walker <robert.walker@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-25coresight: tpiu: Cleanup power managementSuzuki K Poulose
Drop the power only when we have successfully probed. Otherwise leave it to the amba probe to do the rest. Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> [Removed extra newline left after original modification] Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-25coresight: perf: Remove set_buffer call backSuzuki K Poulose
In coresight perf mode, we need to prepare the sink before starting a session, which is done via set_buffer call back. We then proceed to enable the tracing. If we fail to start the session successfully, we leave the sink configuration unchanged. In order to make the operation atomic and to avoid yet another call back to clear the buffer, we get rid of the "set_buffer" call back and pass the buffer details via enable() call back to the sink. Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-25coresight: Convert driver messages to dev_dbgSuzuki K Poulose
Convert component enable/disable messages from dev_info to dev_dbg. When used with perf, the components in the paths are enabled/disabled during each schedule of the run, which can flood the dmesg with these messages. Moreover, they are only useful for debug purposes. So, convert such messages to dev_dbg() which can be turned on as needed. Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-15coresight: tpiu: Fix disabling timeoutsRobin Murphy
Probing the TPIU driver under UBSan triggers an out-of-bounds shift warning in coresight_timeout(): ... [ 5.677530] UBSAN: Undefined behaviour in drivers/hwtracing/coresight/coresight.c:929:16 [ 5.685542] shift exponent 64 is too large for 64-bit type 'long unsigned int' ... On closer inspection things are exponentially out of whack because we're passing a bitmask where a bit number should be. Amusingly, it seems that both calls will find their expected values by sheer luck and appear to succeed: 1 << FFCR_FON_MAN ends up at bit 64 which whilst undefined evaluates as zero in practice, while 1 << FFSR_FT_STOPPED finds bit 2 (TCPresent) which apparently is usually tied high. Following the examples of other drivers, define separate FOO and FOO_BIT macros for masks vs. indices, and put things right. CC: Robert Walker <robert.walker@arm.com> CC: Mike Leach <mike.leach@linaro.org> CC: Mathieu Poirier <mathieu.poirier@linaro.org> Fixes: 11595db8e17f ("coresight: Fix disabling of CoreSight TPIU") Signed-off-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-14coresight: Moving framework and drivers to SPDX identifierMathieu Poirier
Moving all kernel side CoreSight framework and drivers to SPDX identifier. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-19coresight: Fix disabling of CoreSight TPIURobert Walker
The CoreSight TPIU should be disabled when tracing to other sinks to allow them to operate at full bandwidth. This patch fixes tpiu_disable_hw() to correctly disable the TPIU by configuring the TPIU to stop on flush, initiating a manual flush, waiting for the flush to complete and then waits for the TPIU to indicate it has stopped. Signed-off-by: Robert Walker <robert.walker@arm.com> Tested-by: Mike Leach <mike.leach@linaro.org> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-19coresight: Use PTR_ERR_OR_ZERO()Vasyl Gomonovych
Fix ptr_ret.cocci warnings: drivers/hwtracing/coresight/coresight-tpiu.c:163:1-3: WARNING: PTR_ERR_OR_ZERO can be used drivers/hwtracing/coresight/coresight-funnel.c:217:1-3: WARNING: PTR_ERR_OR_ZERO can be used drivers/hwtracing/coresight/coresight-dynamic-replicator.c:166:1-3: WARNING: PTR_ERR_OR_ZERO can be used Use PTR_ERR_OR_ZERO rather than if(IS_ERR(...)) + PTR_ERR Generated by: scripts/coccinelle/api/ptr_ret.cocci Signed-off-by: Vasyl Gomonovych <gomonovych@gmail.com> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-20coresight: Extend the PIDR mask to cover relevant bits in PIDR2Suzuki K Poulose
As per coresight standards, PIDR2 register has the following format : [2-0] - JEP106_bits6to4 [3] - JEDEC, designer ID is specified by JEDEC. However some of the drivers only use mask of 0x3 for the PIDR2 leaving bits [3-2] unchecked, which could potentially match the component for a different device altogether. This patch fixes the mask and the corresponding id bits for the existing devices. Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Cc: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-28coresight: tpiu: constify amba_idArvind Yadav
amba_id are not supposed to change at runtime. All functions working with const amba_id. So mark the non-const structs as const. Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-28coresight: Add support for Coresight SoC 600 componentsSuzuki K Poulose
Add the peripheral ids for the Coresight SoC 600 TPIU, replicator and funnel. Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31coresight: Use local coresight_desc instancesSuzuki K Poulose
Each coresight device prepares a description for coresight_register() in struct coresight_desc. Once we register the device, the description is useless and can be freed. The coresight_desc is small enough (48bytes on 64bit)i to be allocated on the stack. Hence use an automatic variable to avoid a needless dynamic allocation and wasting the memory(which will only be free'd when the device is destroyed). Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Cc: Pratik Patel <pratikp@codeaurora.org> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-01coresight: removing gratuitous boot time log messagesMathieu Poirier
Removing boot time log for drivers that don't report useful information other than they came up properly. The same information can be found in sysFS once the system has booted and as such doesn't provide any value in the boot log. Reported-by: Mark Brown <broonie@linaro.org> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-20drivers/hwtracing: make coresight-* explicitly non-modularPaul Gortmaker
None of the Kconfig currently controlling compilation of any of the files here are tristate, meaning that none of it currently is being built as a module by anyone. We need not be concerned about .remove functions and blocking the unbind sysfs operations, since that was already done in a recent commit. Lets remove any remaining modular references, so that when reading the drivers there is no doubt they are builtin-only. All drivers get mostly the same changes, so they are handled in batch. Changes are (1) convert to builtin_amba_driver, (2) delete module.h include where unused, and (3) relocate the description into the comments so we don't need MODULE_DESCRIPTION and associated tags. The etm3x and etm4x use module_param_named, and have been adjusted to just include moduleparam.h for that purpose. In commit f309d4443130bf814e991f836e919dca22df37ae ("platform_device: better support builtin boilerplate avoidance") we introduced the builtin_driver macro. Here we use that support and extend it to amba driver registration, so where a driver is clearly non-modular and builtin-only, we can update with the simple mapping of module_amba_driver(...) ---> builtin_amba_driver(...) Since module_amba_driver() uses the same init level priority as builtin_amba_driver() the init ordering remains unchanged with this commit. Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Cc: linux-arm-kernel@lists.infradead.org Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-20coresight: etb10: adding operation mode for sink->enable()Mathieu Poirier
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>
2016-02-20coresight: moving PM runtime operations to core frameworkMathieu Poirier
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>
2016-02-07coresight: removing bind/unbind options from sysfsMathieu Poirier
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>
2015-05-24coresight: tpiu: retrieve and handle atclkLinus Walleij
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>
2015-05-24coresight: tpiu: let runtime PM handle core clockLinus Walleij
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>
2015-05-24coresight: support the TPIU version found in Ux500Linus Walleij
The Ux500 has a PrimeCell version 4B instead of the 3B as supported by the driver, extend the match table to cover this version. 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>
2015-04-03coresight: moving to new "hwtracing" directoryMathieu Poirier
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: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>