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path: root/drivers/hwtracing/coresight/coresight-tmc-etr.c (follow)
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2018-09-25coreisght: tmc: Claim device before useSuzuki K Poulose1-0/+4
Use CLAIM tags to make sure the device is available for use. 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: tmc-etr: Handle errors enabling CATUSuzuki K Poulose1-7/+12
Make sure we honor the errors in CATU device and abort the operation. While at it, delay setting the etr_buf for the session until we are sure that we are indeed enabling the ETR. 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: tmc-etr: Refactor for handling errorsSuzuki K Poulose1-24/+43
Refactor the tmc-etr enable operation to make it easier to handle errors in enabling the hardware. We need to make sure that the buffer is compatible with the ETR. This patch re-arranges to make the error handling easier, by deferring the hardware enablement until all the errors are checked. This also avoids turning the CATU on/off during a sysfs read session. 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: etm-perf: Add support for ETR backendSuzuki K Poulose1-2/+246
Add support for using TMC-ETR as backend for ETM perf tracing. We use software double buffering at the moment. i.e, the TMC-ETR uses a separate buffer than the perf ring buffer. The data is copied to the perf ring buffer once a session completes. The TMC-ETR would try to match the larger of perf ring buffer or the ETR buffer size configured via sysfs, scaling down to a minimum limit of 1MB. 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: perf: Remove set_buffer call backSuzuki K Poulose1-3/+4
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 Poulose1-2/+2
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>
2018-09-25coresight: tmc-etr: Relax collection of trace from sysfs modeSuzuki K Poulose1-8/+6
Since the ETR now uses mode specific buffers, we can reliably provide the trace data captured in sysfs mode, even when the ETR is operating in PERF mode. 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: tmc-etr: Handle driver mode specific ETR buffersSuzuki K Poulose1-20/+38
Since the ETR could be driven either by SYSFS or by perf, it becomes complicated how we deal with the buffers used for each of these modes. The ETR driver cannot simply free the current attached buffer without knowing the provider (i.e, sysfs vs perf). To solve this issue, we provide: 1) the driver-mode specific etr buffer to be retained in the drvdata 2) the etr_buf for a session should be passed on when enabling the hardware, which will be stored in drvdata->etr_buf. This will be replaced (not free'd) as soon as the hardware is disabled, after necessary sync operation. The advantages of this are : 1) The common code path doesn't need to worry about how to dispose an existing buffer, if it is about to start a new session with a different buffer, possibly in a different mode. 2) The driver mode can control its buffers and can get access to the saved session even when the hardware is operating in a different mode. (e.g, we can still access a trace buffer from a sysfs mode even if the etr is now used in perf mode, without disrupting the current session.) Towards this, we introduce a sysfs specific data which will hold the etr_buf used for sysfs mode of operation, controlled solely by the sysfs mode handling code. 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: Use ERR_CAST instead of ERR_PTRzhong jiang1-1/+1
Use ERR_CAT inlined function to replace the ERR_PTR(PTR_ERR). It make the code more concise. Signed-off-by: zhong jiang <zhongjiang@huawei.com> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-15coresight: catu: Plug in CATU as a backend for ETR bufferSuzuki K Poulose1-6/+19
Now that we can use a CATU with a scatter gather table, add support for the TMC ETR to make use of the connected CATU in translate mode. This is done by adding CATU as new buffer mode. 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: Introduce support for Coresight Address Translation UnitSuzuki K Poulose1-0/+52
Add the initial support for Coresight Address Translation Unit, which augments the TMC in Coresight SoC-600 by providing an improved Scatter Gather mechanism. CATU is always connected to a single TMC-ETR and converts the AXI address with a translated address (from a given SG table with specific format). The CATU should be programmed in pass through mode and enabled even if the ETR doesn't use the translation by CATU. This patch provides mechanism to enable/disable the CATU always in the pass through mode. We reuse the existing ports mechanism to link the TMC-ETR to the connected CATU. i.e, TMC-ETR:output_port0 -> CATU:input_port0 Reference manual for CATU component is avilable in version r2p0 of : "Arm Coresight System-on-Chip SoC-600 Technical Reference Manual". 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: Fix check in coresight_tmc_etr_buf_insert_barrier_packetSuzuki K Poulose1-1/+1
We request for "CORESIGHT_BARRIER_PKT_SIZE" length and we should be happy when we get that size. 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: include vmalloc.h for vmap/vunmapArnd Bergmann1-0/+1
The newly introduced code fails to build in some configurations unless we include the right headers: drivers/hwtracing/coresight/coresight-tmc-etr.c: In function 'tmc_free_table_pages': drivers/hwtracing/coresight/coresight-tmc-etr.c:206:3: error: implicit declaration of function 'vunmap'; did you mean 'iounmap'? [-Werror=implicit-function-declaration] Fixes: 79613ae8715a ("coresight: Add generic TMC sg table framework") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-15coresight: tmc-etr buf: Add TMC scatter gather mode backendSuzuki K Poulose1-4/+110
Add the support for Scatter-Gather mode to the etr-buf layer. Since we now have two different modes, we choose the backend based on a set of conditions, documented in the code. 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: tmc-etr: Add transparent buffer managementSuzuki K Poulose1-80/+262
The TMC-ETR can use the target trace buffer in two different modes. Normal physically contiguous mode and a discontiguous list pages in Scatter-Gather mode. Also we have dedicated Coresight component, CATU (Coresight Address Translation Unit) to provide improved scatter-gather mode in Coresight SoC-600. This complicates the management of the buffer used for trace, depending on the mode in which ETR is configured. So, this patch adds a transparent layer for managing the ETR buffer which abstracts the basic operations on the buffer (alloc, free, sync and retrieve the data) and uses the mode specific helpers to do the actual operation. This also allows the ETR driver to choose the best mode for a given use case and adds the flexibility to fallback to a different mode, without duplicating the code. The patch also adds the "normal" flat memory mode and switches the sysfs driver to use the new layer. 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: Add support for TMC ETR SG unitSuzuki K Poulose1-0/+263
This patch adds support for setting up an SG table used by the TMC ETR inbuilt SG unit. The TMC ETR uses 4K page sized tables to hold pointers to the 4K data pages with the last entry in a table pointing to the next table with the entries, by kind of chaining. The 2 LSBs determine the type of the table entry, to one of : Normal - Points to a 4KB data page. Last - Points to a 4KB data page, but is the last entry in the page table. Link - Points to another 4KB table page with pointers to data. The code takes care of handling the system page size which could be different than 4K. So we could end up putting multiple ETR SG tables in a single system page, vice versa for the data pages. 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: Add generic TMC sg table frameworkSuzuki K Poulose1-0/+268
This patch introduces a generic sg table data structure and associated operations. An SG table can be used to map a set of Data pages where the trace data could be stored by the TMC ETR. The information about the data pages could be stored in different formats, depending on the type of the underlying SG mechanism (e.g, TMC ETR SG vs Coresight CATU). The generic structure provides book keeping of the pages used for the data as well as the table contents. The table should be filled by the user of the infrastructure. A table can be created by specifying the number of data pages as well as the number of table pages required to hold the pointers, where the latter could be different for different types of tables. The pages are mapped in the appropriate dma data direction mode (i.e, DMA_TO_DEVICE for table pages and DMA_FROM_DEVICE for data pages). The framework can optionally accept a set of allocated data pages (e.g, perf ring buffer) and map them accordingly. The table and data pages are vmap'ed to allow easier access by the drivers. The framework also provides helpers to sync the data written to the pages with appropriate directions. This will be later used by the TMC ETR SG unit and CATU. 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: Add helper for inserting synchronization packetsSuzuki K Poulose1-12/+1
Right now we open code filling the trace buffer with synchronization packets when the circular buffer wraps around in different drivers. Move this to a common place. While at it, clean up the barrier_pkt array to strip off the trailing '\0'. Cc: Mathieu Poirier <mathieu.poirier@linaro.org> 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> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-15coresight: tmc-etr: Disallow perf modeSuzuki K Poulose1-26/+2
We don't support ETR in perf mode yet. So, don't even try to enable the hardware, even by mistake. 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: tmc-etr: Do not clean trace bufferSuzuki K Poulose1-6/+2
We zero out the entire trace buffer used for ETR before it is enabled, for helping with debugging. With the addition of scatter-gather mode, the buffer could be bigger and non-contiguous. Get rid of this step; if someone wants to debug, they can always add it as and when 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: tmc: Hide trace buffer handling for file readSuzuki K Poulose1-0/+34
At the moment we adjust the buffer pointers for reading the trace data via misc device in the common code for ETF/ETB and ETR. Since we are going to change how we manage the buffer for ETR, let us move the buffer manipulation to the respective driver files, hiding it from the common code. We do so by adding type specific helpers for finding the length of data and the pointer to the buffer, for a given length at a file position. 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>
2018-05-14coresight tmc etr: Removing extra newlineMathieu Poirier1-1/+0
The simple removal of an extra newline, no change in functionality. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-14coresight tmc etr: Fix uninitialised variableMathieu Poirier1-1/+1
Variable 'paddr' can't be used if uninitialised but is nonetheless confusing to some static checker. As such simply initialise it to zero. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-14coresight tmc etr: Make memory check consistent in the same functionMathieu Poirier1-2/+2
While operating from sysFS the TMC-ETR driver needs to make sure it has memory to work with but doesn't allocate memory uselessly either. Since the main memory handle for this driver is drvdata::vaddr, use it throughout function tmc_enable_etr_sink_sysfs() so that things are consistent. Reported-by: Dan Carpenter <dan.carpenter@oracle.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 Poirier1-12/+1
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>
2017-08-28coresight tmc: Support for save-restore in ETRSuzuki K Poulose1-1/+12
The Coresight SoC 600 TMC ETR supports save-restore feature, where the values of the RRP/RWP and STS.Full are retained when it leaves the Disabled state. Hence, we must program the RRP/RWP and STS.Full to a proper value. For now, set the RRP/RWP to the base address of the buffer and clear the STS.Full register. This can be later exploited for proper save-restore of ETR trace contexts (e.g, perf). Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-08-28coresight tmc etr: Setup AXI cache encoding for read transfersSuzuki K Poulose1-0/+6
If the ETR supports split cache encoding (i.e, separate bits for read and write transfers) unlike the older version (where read and write transfers use the same encoding in AXICTL[2-5]). This feature is not advertised and has to be described by the static mask associated with the device id. 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>
2017-08-28coresight tmc etr: Cleanup AXICTL register handlingSuzuki K Poulose1-7/+3
This patch cleans up how we setup the AXICTL register on TMC ETR. At the moment we don't set the CacheCtrl bits, which drives the arcache and awcache bits on AXI bus specifying the cacheablitiy. Set this to Write-back Read and Write-allocate. 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>
2017-08-28coresight tmc: Add helpers for accessing 64bit registersSuzuki K Poulose1-4/+4
Coresight TMC splits 64bit registers into a pair of 32bit registers (e.g DBA, RRP, RWP). Provide helpers to read/write to these registers. 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>
2017-08-28coresight: Add barrier packet for synchronisationMathieu Poirier1-0/+12
When a buffer overflow happens the synchronisation patckets usually present at the beginning of the buffer are lost, a situation that prevents the decoder from knowing the context of the traces being decoded. This patch adds a barrier packet to be used by sink IPs when a buffer overflow condition is detected. These barrier packets are then used by the decoding library as markers to force re-synchronisation. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-11-29coresight: tmc: Remove duplicate memsetSuzuki K. Poulose1-2/+0
The tmc_etr_enable_hw() fills the buffer with 0's before enabling the hardware. So, we don't need an explicit memset() in tmc_enable_etr_sink_sysfs() before calling the tmc_etr_enable_hw(). This patch removes the explicit memset from tmc_enable_etr_sink_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>
2016-11-29coresight: tmc: Get rid of mode parameter for helper routinesSuzuki K. Poulose1-11/+4
Get rid of the superfluous mode parameter and the check for the mode in tmc_etX_enable_sink_{perf/sysfs}. While at it, also remove the unnecessary WARN_ON() checks. 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>
2016-11-29coresight: tmc: Cleanup operation mode handlingSuzuki K. Poulose1-15/+11
The mode of operation of the TMC tracked in drvdata->mode is defined as a local_t type. This is always checked and modified under the drvdata->spinlock and hence we don't need local_t for it and the unnecessary synchronisation instructions that comes with it. This change makes the code a bit more cleaner. Also fixes the order in which we update the drvdata->mode to CS_MODE_DISABLED. i.e, in tmc_disable_etX_sink we change the mode to CS_MODE_DISABLED before invoking tmc_disable_etX_hw() which in turn depends on the mode to decide whether to dump the trace to a buffer. Applies on mathieu's coresight/next tree [1] https://git.linaro.org/kernel/coresight.git next Reported-by: Venkatesh Vivekanandan <venkatesh.vivekanandan@broadcom.com> 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>
2016-09-09coresight: tmc: mark symbols static where possibleBaoyou Xie1-1/+1
We get a few warnings when building kernel with W=1: drivers/hwtracing/coresight/coresight-tmc-etr.c:23:6: warning: no previous prototype for 'tmc_etr_enable_hw' [-Wmissing-prototypes] drivers/hwtracing/coresight/coresight-tmc-etf.c:25:6: warning: no previous prototype for 'tmc_etb_enable_hw' [-Wmissing-prototypes] drivers/hwtracing/coresight/coresight-tmc.c:250:9: warning: no previous prototype for ‘trigger_cntr_show’ [-Wmissing-prototypes] ... In fact, these functions are only used in the file in which they are declared and don't need a declaration, but can be made static. so this patch marks these functions with 'static'. Signed-off-by: Baoyou Xie <baoyou.xie@linaro.org> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-08-31coresight: Cleanup TMC status checkSuzuki K Poulose1-1/+1
Use the defined symbol rather than hardcoding the value to check whether the TMC buffer is full. 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: tmc: Limit the trace to available dataSuzuki K Poulose1-3/+9
At present the ETF or ETR gives out the entire device buffer, even if there is less or even no trace data available. This patch limits the trace data given out to the actual trace data collected. Cc: 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>
2016-06-16coresight: Fix erroneous memset in tmc_read_unprepare_etrSuzuki K Poulose1-6/+3
At the end of a trace collection, we try to clear the entire buffer and enable the ETR back if it was already enabled. But, we would have adjusted the drvdata->buf to point to the beginning of the trace data in the trace buffer @drvdata->vaddr. So, the following code which clears the buffer is dangerous and can cause crashes, like below : memset(drvdata->buf, 0, drvdata->size); Unable to handle kernel paging request at virtual address ffffff800a145000 pgd = ffffffc974726000 *pgd=00000009f3e91003, *pud=00000009f3e91003, *pmd=0000000000000000 PREEMPT SMP Modules linked in: CPU: 4 PID: 1692 Comm: dd Not tainted 4.7.0-rc2+ #1721 Hardware name: ARM Juno development board (r0) (DT) task: ffffffc9734a0080 ti: ffffffc974460000 task.ti: ffffffc974460000 PC is at __memset+0x1ac/0x200 LR is at tmc_read_unprepare_etr+0x144/0x1bc pc : [<ffffff80083a05ac>] lr : [<ffffff800859c984>] pstate: 200001c5 ... [<ffffff80083a05ac>] __memset+0x1ac/0x200 [<ffffff800859b2e4>] tmc_release+0x90/0x94 [<ffffff8008202f58>] __fput+0xa8/0x1ec [<ffffff80082030f4>] ____fput+0xc/0x14 [<ffffff80080c3ef8>] task_work_run+0xb0/0xe4 [<ffffff8008088bf4>] do_notify_resume+0x64/0x6c [<ffffff8008084d5c>] work_pending+0x10/0x14 Code: 91010108 54ffff4a 8b040108 cb050042 (d50b7428) Since we clear the buffer anyway in the following call to tmc_etr_enable_hw(), remove the erroneous memset(). Fixes: commit de5461970b3e9e1 ("coresight: tmc: allocating memory when 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>
2016-06-16coresight: Fix tmc_read_unprepare_etrSuzuki K Poulose1-1/+1
At the end of the trace capture, we free the allocated memory, resetting the drvdata->buf to NULL, to indicate that trace data was collected and the next trace session should allocate the memory in tmc_enable_etr_sink_sysfs. The tmc_enable_etr_sink_sysfs, we only allocate memory if drvdata->vaddr is not NULL (which is not performed at the end of previous session). This can cause, drvdata->vaddr getting assigned NULL and later we do memset() which causes a crash as below : Unable to handle kernel NULL pointer dereference at virtual address 00000000 pgd = ffffffc9747f0000 [00000000] *pgd=00000009f402e003, *pud=00000009f402e003, *pmd=0000000000000000 Internal error: Oops: 96000046 [#1] PREEMPT SMP Modules linked in: CPU: 0 PID: 1592 Comm: bash Not tainted 4.7.0-rc1+ #1712 Hardware name: ARM Juno development board (r0) (DT) task: ffffffc078fe0080 ti: ffffffc974178000 task.ti: ffffffc974178000 PC is at __memset+0x1ac/0x200 LR is at tmc_enable_etr_sink+0xf8/0x304 pc : [<ffffff80083a002c>] lr : [<ffffff800859be44>] pstate: 400001c5 sp : ffffffc97417bc00 x29: ffffffc97417bc00 x28: ffffffc974178000 Call trace: Exception stack(0xffffffc97417ba40 to 0xffffffc97417bb60) ba40: 0000000000000001 ffffffc974a5d098 ffffffc97417bc00 ffffff80083a002c ba60: ffffffc974a5d118 0000000000000000 0000000000000000 0000000000000000 ba80: 0000000000000001 0000000000000000 ffffff800859bdec 0000000000000040 baa0: ffffff8008b45b58 00000000000001c0 ffffffc97417baf0 ffffff80080eddb4 bac0: 0000000000000003 ffffffc078fe0080 ffffffc078fe0960 ffffffc078fe0940 bae0: 0000000000000000 0000000000000000 00000000007fffc0 0000000000000004 bb00: 0000000000000000 0000000000000040 000000000000003f 0000000000000000 bb20: 0000000000000000 0000000000000000 0000000000000000 0000000000000001 bb40: ffffffc078fe0960 0000000000000018 ffffffffffffffff 0008669628000000 [<ffffff80083a002c>] __memset+0x1ac/0x200 [<ffffff8008599814>] coresight_enable_path+0xa8/0x1dc [<ffffff8008599b10>] coresight_enable+0x88/0x1b8 [<ffffff8008599d88>] enable_source_store+0x3c/0x6c [<ffffff800845eaf4>] dev_attr_store+0x18/0x28 [<ffffff80082829e8>] sysfs_kf_write+0x54/0x64 [<ffffff8008281c30>] kernfs_fop_write+0x148/0x1d8 [<ffffff8008200128>] __vfs_write+0x28/0x110 [<ffffff8008200e88>] vfs_write+0xa0/0x198 [<ffffff80082021b0>] SyS_write+0x44/0xa0 [<ffffff8008084e70>] el0_svc_naked+0x24/0x28 Code: 91010108 54ffff4a 8b040108 cb050042 (d50b7428) This patch fixes the issue by clearing the drvdata->vaddr while we free the allocated buffer at the end of a session, so that we allocate the memory again. Cc: 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>
2016-05-03coresight: tmc: make sysFS and Perf mode mutually exclusiveMathieu Poirier1-3/+59
The sysFS and Perf access methods can't be allowed to interfere with one another. As such introducing guards to access functions that prevents moving forward if a TMC is already being used. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-03coresight: tmc: dump system memory content only when neededMathieu Poirier1-1/+6
Calling tmc_etf/etr_dump_hw() is required only when operating from sysFS. When working from Perf, the system memory is harvested from the AUX trace API. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-03coresight: tmc: adding mode of operation for link/sinksMathieu Poirier1-5/+18
Moving tmc_drvdata::enable to a local_t mode. That way the sink interface is aware of it's orgin and the foundation for mutual exclusion between the sysFS and Perf interface can be laid out. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-03coresight: tmc: getting rid of multiple read accessMathieu Poirier1-0/+4
Allowing multiple readers to access the trace data simultaniously via sysFS provides no shortage of opportunity for race condition, mandates two variable to be maintained (drvdata::read_count and drvdata::reading), makes the code complex and provide little advantages, if any. This patch streamlines the read process by restricting trace data access to a single user. That way drvdata::read_count can be eliminated and race conditions (along with faulty error handling) in function tmc_open() and tmc_release() eliminated. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-03coresight: tmc: allocating memory when neededMathieu Poirier1-5/+88
In it's current form the TMC probe() function allocates trace buffer memory at boot time, event if coresight isn't used. This is highly inefficient since trace buffers can occupy a lot of memory that could be used otherwised. This patch allocates trace buffers on the fly, when the coresight subsystem is solicited. Allocated buffers are released when traces are read using the device descriptors under /dev. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-03coresight: tmc: making prepare/unprepare functions genericMathieu Poirier1-1/+41
Dealing with HW related matters in tmc_read_prepare/unprepare becomes convoluted when many cases need to be handled distinctively. As such moving processing related to HW setup to individual driver files and keep the core driver generic. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-05-03coresight: tmc: splitting driver in ETB/ETF and ETR componentsMathieu Poirier1-0/+128
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: Mathieu Poirier <mathieu.poirier@linaro.org> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>