[PATCH 0/8] coresight: next v4.9-rc4

[PATCH 0/8] coresight: next v4.9-rc4

[Mathieu Poirier]

Good morning Greg,

Please consider the following set for inclusion in the 4.10 cycle. It
applies cleanly on today 'char-misc-next' branch (3372592a140d).

Regards,
Mathieu

Chunyan Zhang (1):
  coresight: stm: return error code instead of zero in .packet()

Mathieu Poirier (1):
  coresight: reset "enable_sink" flag when need be

Muhammad Abdul WAHAB (2):
  coresight: etm3x: indentation fix (extra space removed)
  coresight: etm3x: Adding missing features of Coresight PTM components

Suzuki K Poulose (1):
  coresight: Add support for ARM Coresight STM-500

Suzuki K. Poulose (3):
  coresight: tmc: Cleanup operation mode handling
  coresight: tmc: Get rid of mode parameter for helper routines
  coresight: tmc: Remove duplicate memset

 drivers/hwtracing/coresight/coresight-etm-perf.c   | 31 ++++-----
 drivers/hwtracing/coresight/coresight-etm.h        |  5 ++
 .../hwtracing/coresight/coresight-etm3x-sysfs.c    | 12 +++-
 drivers/hwtracing/coresight/coresight-priv.h       |  4 +-
 drivers/hwtracing/coresight/coresight-stm.c        |  9 ++-
 drivers/hwtracing/coresight/coresight-tmc-etf.c    | 48 ++++++--------
 drivers/hwtracing/coresight/coresight-tmc-etr.c    | 43 +++++--------
 drivers/hwtracing/coresight/coresight-tmc.h        |  2 +-
 drivers/hwtracing/coresight/coresight.c            | 74 ++++++++++++++++++++--
 9 files changed, 144 insertions(+), 84 deletions(-)

-- 
2.7.4

[PATCH 1/8] coresight: stm: return error code instead of zero in .packet()

[Mathieu Poirier]

From: Chunyan Zhang <zhang.chunyan@linaro.org>

In STM framework driver, the trace data writing loop would keep running
until it received a negative return value or the whole trace packet has
been written to STM device.  So if the .packet() of STM device always
returns zero since the device is not enabled or the parameter isn't
supported, STM framework driver will stall into a dead loop.

Returning -EACCES (Permission denied) in .packet() if the device is
disabled makes more sense, and this is the same for returning -EINVAL
if the channel passed into is not supported.

Signed-off-by: Chunyan Zhang <zhang.chunyan@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
 drivers/hwtracing/coresight/coresight-stm.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-stm.c b/drivers/hwtracing/coresight/coresight-stm.c
index 49e0f1b925a5..d397849c2c6a 100644
--- a/drivers/hwtracing/coresight/coresight-stm.c
+++ b/drivers/hwtracing/coresight/coresight-stm.c
@@ -419,10 +419,10 @@ static ssize_t stm_generic_packet(struct stm_data *stm_data,
 						   struct stm_drvdata, stm);
 
 	if (!(drvdata && local_read(&drvdata->mode)))
-		return 0;
+		return -EACCES;
 
 	if (channel >= drvdata->numsp)
-		return 0;
+		return -EINVAL;
 
 	ch_addr = (unsigned long)stm_channel_addr(drvdata, channel);
 
-- 
2.7.4

[PATCH 2/8] coresight: etm3x: indentation fix (extra space removed)

[Mathieu Poirier]

From: Muhammad Abdul WAHAB <muhammadabdul.wahab@centralesupelec.fr>

An extra space is removed.

Signed-off-by: Muhammad Abdul Wahab <muhammadabdul.wahab@centralesupelec.fr>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
 drivers/hwtracing/coresight/coresight-etm3x-sysfs.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/hwtracing/coresight/coresight-etm3x-sysfs.c b/drivers/hwtracing/coresight/coresight-etm3x-sysfs.c
index e9b071953f80..5ea090955c08 100644
--- a/drivers/hwtracing/coresight/coresight-etm3x-sysfs.c
+++ b/drivers/hwtracing/coresight/coresight-etm3x-sysfs.c
@@ -146,7 +146,7 @@ static ssize_t mode_store(struct device *dev,
 			goto err_unlock;
 		}
 		config->ctrl |= ETMCR_STALL_MODE;
-	 } else
+	} else
 		config->ctrl &= ~ETMCR_STALL_MODE;
 
 	if (config->mode & ETM_MODE_TIMESTAMP) {
-- 
2.7.4

[PATCH 3/8] coresight: etm3x: Adding missing features of Coresight PTM components

[Mathieu Poirier]

From: Muhammad Abdul WAHAB <muhammadabdul.wahab@centralesupelec.fr>

In the current driver for Coresight components, two features of PTM
components are missing:

1. Branch Broadcasting (present also in ETM but called Branch Output)
2. Return Stack (only present in PTM v1.0 and PTMv1.1)

These features can be added simply to the code using `mode` field of
`etm_config` struct.

1. **Branch Broadcast** : The branch broadcast feature is present in ETM
components as well and is called Branch output. It allows to retrieve
addresses for direct branch addresses alongside the indirect branch
addresses. For example, it could be useful in cases when tracing without
source code.
2. **Return Stack** : The return stack option allows to retrieve the
return addresses of function calls. It can be useful to avoid CRA
(Code Reuse Attacks) by keeping a shadowstack.

Signed-off-by: Muhammad Abdul Wahab <muhammadabdul.wahab@centralesupelec.fr>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
 drivers/hwtracing/coresight/coresight-etm.h         |  5 +++++
 drivers/hwtracing/coresight/coresight-etm3x-sysfs.c | 10 ++++++++++
 2 files changed, 15 insertions(+)

diff --git a/drivers/hwtracing/coresight/coresight-etm.h b/drivers/hwtracing/coresight/coresight-etm.h
index 4a18ee499965..ad063d7444e1 100644
--- a/drivers/hwtracing/coresight/coresight-etm.h
+++ b/drivers/hwtracing/coresight/coresight-etm.h
@@ -89,11 +89,13 @@
 /* ETMCR - 0x00 */
 #define ETMCR_PWD_DWN		BIT(0)
 #define ETMCR_STALL_MODE	BIT(7)
+#define ETMCR_BRANCH_BROADCAST	BIT(8)
 #define ETMCR_ETM_PRG		BIT(10)
 #define ETMCR_ETM_EN		BIT(11)
 #define ETMCR_CYC_ACC		BIT(12)
 #define ETMCR_CTXID_SIZE	(BIT(14)|BIT(15))
 #define ETMCR_TIMESTAMP_EN	BIT(28)
+#define ETMCR_RETURN_STACK	BIT(29)
 /* ETMCCR - 0x04 */
 #define ETMCCR_FIFOFULL		BIT(23)
 /* ETMPDCR - 0x310 */
@@ -110,8 +112,11 @@
 #define ETM_MODE_STALL		BIT(2)
 #define ETM_MODE_TIMESTAMP	BIT(3)
 #define ETM_MODE_CTXID		BIT(4)
+#define ETM_MODE_BBROAD		BIT(5)
+#define ETM_MODE_RET_STACK	BIT(6)
 #define ETM_MODE_ALL		(ETM_MODE_EXCLUDE | ETM_MODE_CYCACC | \
 				 ETM_MODE_STALL | ETM_MODE_TIMESTAMP | \
+				 ETM_MODE_BBROAD | ETM_MODE_RET_STACK | \
 				 ETM_MODE_CTXID | ETM_MODE_EXCL_KERN | \
 				 ETM_MODE_EXCL_USER)
 
diff --git a/drivers/hwtracing/coresight/coresight-etm3x-sysfs.c b/drivers/hwtracing/coresight/coresight-etm3x-sysfs.c
index 5ea090955c08..ca98ad13bb8c 100644
--- a/drivers/hwtracing/coresight/coresight-etm3x-sysfs.c
+++ b/drivers/hwtracing/coresight/coresight-etm3x-sysfs.c
@@ -164,6 +164,16 @@ static ssize_t mode_store(struct device *dev,
 	else
 		config->ctrl &= ~ETMCR_CTXID_SIZE;
 
+	if (config->mode & ETM_MODE_BBROAD)
+		config->ctrl |= ETMCR_BRANCH_BROADCAST;
+	else
+		config->ctrl &= ~ETMCR_BRANCH_BROADCAST;
+
+	if (config->mode & ETM_MODE_RET_STACK)
+		config->ctrl |= ETMCR_RETURN_STACK;
+	else
+		config->ctrl &= ~ETMCR_RETURN_STACK;
+
 	if (config->mode & (ETM_MODE_EXCL_KERN | ETM_MODE_EXCL_USER))
 		etm_config_trace_mode(config);
 
-- 
2.7.4

[PATCH 4/8] coresight: reset "enable_sink" flag when need be

[Mathieu Poirier]

When using coresight from the perf interface sinks are specified
as part of the perf command line.  As such the sink needs to be
disabled once it has been acknowledged by the coresight framework.
Otherwise the sink stays enabled, which may interfere with other
sessions.

This patch removes the sink selection check from the build path
process and make it a function on it's own.  The function is
then used when operating from sysFS or perf to determine what
sink has been selected.

If operated from perf the status of the "enable_sink" flag is
reset so that concurrent session can use a different sink.  When
used from sysFS the status of the flag is left untouched since
users have full control.

The implementation doesn't handle a scenario where a sink has
been enabled from sysFS and another sink is selected from the
perf command line as both modes of operation are mutually
exclusive.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
---
 drivers/hwtracing/coresight/coresight-etm-perf.c | 31 +++++-----
 drivers/hwtracing/coresight/coresight-priv.h     |  4 +-
 drivers/hwtracing/coresight/coresight.c          | 74 ++++++++++++++++++++++--
 3 files changed, 87 insertions(+), 22 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c
index 2cd7c718198a..5a346fc8ce06 100644
--- a/drivers/hwtracing/coresight/coresight-etm-perf.c
+++ b/drivers/hwtracing/coresight/coresight-etm-perf.c
@@ -202,6 +202,21 @@ static void *etm_setup_aux(int event_cpu, void **pages,
 	if (!event_data)
 		return NULL;
 
+	/*
+	 * In theory nothing prevent tracers in a trace session from being
+	 * associated with different sinks, nor having a sink per tracer.  But
+	 * until we have HW with this kind of topology we need to assume tracers
+	 * in a trace session are using the same sink.  Therefore go through
+	 * the coresight bus and pick the first enabled sink.
+	 *
+	 * When operated from sysFS users are responsible to enable the sink
+	 * while from perf, the perf tools will do it based on the choice made
+	 * on the cmd line.  As such the "enable_sink" flag in sysFS is reset.
+	 */
+	sink = coresight_get_enabled_sink(true);
+	if (!sink)
+		return NULL;
+
 	INIT_WORK(&event_data->work, free_event_data);
 
 	mask = &event_data->mask;
@@ -219,25 +234,11 @@ static void *etm_setup_aux(int event_cpu, void **pages,
 		 * list of devices from source to sink that can be
 		 * referenced later when the path is actually needed.
 		 */
-		event_data->path[cpu] = coresight_build_path(csdev);
+		event_data->path[cpu] = coresight_build_path(csdev, sink);
 		if (IS_ERR(event_data->path[cpu]))
 			goto err;
 	}
 
-	/*
-	 * In theory nothing prevent tracers in a trace session from being
-	 * associated with different sinks, nor having a sink per tracer.  But
-	 * until we have HW with this kind of topology and a way to convey
-	 * sink assignement from the perf cmd line we need to assume tracers
-	 * in a trace session are using the same sink.  Therefore pick the sink
-	 * found at the end of the first available path.
-	 */
-	cpu = cpumask_first(mask);
-	/* Grab the sink at the end of the path */
-	sink = coresight_get_sink(event_data->path[cpu]);
-	if (!sink)
-		goto err;
-
 	if (!sink_ops(sink)->alloc_buffer)
 		goto err;
 
diff --git a/drivers/hwtracing/coresight/coresight-priv.h b/drivers/hwtracing/coresight/coresight-priv.h
index 196a14be4b3d..ef9d8e93e3b2 100644
--- a/drivers/hwtracing/coresight/coresight-priv.h
+++ b/drivers/hwtracing/coresight/coresight-priv.h
@@ -111,7 +111,9 @@ static inline void CS_UNLOCK(void __iomem *addr)
 void coresight_disable_path(struct list_head *path);
 int coresight_enable_path(struct list_head *path, u32 mode);
 struct coresight_device *coresight_get_sink(struct list_head *path);
-struct list_head *coresight_build_path(struct coresight_device *csdev);
+struct coresight_device *coresight_get_enabled_sink(bool reset);
+struct list_head *coresight_build_path(struct coresight_device *csdev,
+				       struct coresight_device *sink);
 void coresight_release_path(struct list_head *path);
 
 #ifdef CONFIG_CORESIGHT_SOURCE_ETM3X
diff --git a/drivers/hwtracing/coresight/coresight.c b/drivers/hwtracing/coresight/coresight.c
index 7bf00a0beb6f..0c37356e417c 100644
--- a/drivers/hwtracing/coresight/coresight.c
+++ b/drivers/hwtracing/coresight/coresight.c
@@ -368,6 +368,52 @@ struct coresight_device *coresight_get_sink(struct list_head *path)
 	return csdev;
 }
 
+static int coresight_enabled_sink(struct device *dev, void *data)
+{
+	bool *reset = data;
+	struct coresight_device *csdev = to_coresight_device(dev);
+
+	if ((csdev->type == CORESIGHT_DEV_TYPE_SINK ||
+	     csdev->type == CORESIGHT_DEV_TYPE_LINKSINK) &&
+	     csdev->activated) {
+		/*
+		 * Now that we have a handle on the sink for this session,
+		 * disable the sysFS "enable_sink" flag so that possible
+		 * concurrent perf session that wish to use another sink don't
+		 * trip on it.  Doing so has no ramification for the current
+		 * session.
+		 */
+		if (*reset)
+			csdev->activated = false;
+
+		return 1;
+	}
+
+	return 0;
+}
+
+/**
+ * coresight_get_enabled_sink - returns the first enabled sink found on the bus
+ * @deactivate:	Whether the 'enable_sink' flag should be reset
+ *
+ * When operated from perf the deactivate parameter should be set to 'true'.
+ * That way the "enabled_sink" flag of the sink that was selected can be reset,
+ * allowing for other concurrent perf sessions to choose a different sink.
+ *
+ * When operated from sysFS users have full control and as such the deactivate
+ * parameter should be set to 'false', hence mandating users to explicitly
+ * clear the flag.
+ */
+struct coresight_device *coresight_get_enabled_sink(bool deactivate)
+{
+	struct device *dev = NULL;
+
+	dev = bus_find_device(&coresight_bustype, NULL, &deactivate,
+			      coresight_enabled_sink);
+
+	return dev ? to_coresight_device(dev) : NULL;
+}
+
 /**
  * _coresight_build_path - recursively build a path from a @csdev to a sink.
  * @csdev:	The device to start from.
@@ -380,6 +426,7 @@ struct coresight_device *coresight_get_sink(struct list_head *path)
  * last one.
  */
 static int _coresight_build_path(struct coresight_device *csdev,
+				 struct coresight_device *sink,
 				 struct list_head *path)
 {
 	int i;
@@ -387,15 +434,15 @@ static int _coresight_build_path(struct coresight_device *csdev,
 	struct coresight_node *node;
 
 	/* An activated sink has been found.  Enqueue the element */
-	if ((csdev->type == CORESIGHT_DEV_TYPE_SINK ||
-	     csdev->type == CORESIGHT_DEV_TYPE_LINKSINK) && csdev->activated)
+	if (csdev == sink)
 		goto out;
 
 	/* Not a sink - recursively explore each port found on this element */
 	for (i = 0; i < csdev->nr_outport; i++) {
 		struct coresight_device *child_dev = csdev->conns[i].child_dev;
 
-		if (child_dev && _coresight_build_path(child_dev, path) == 0) {
+		if (child_dev &&
+		    _coresight_build_path(child_dev, sink, path) == 0) {
 			found = true;
 			break;
 		}
@@ -422,18 +469,22 @@ static int _coresight_build_path(struct coresight_device *csdev,
 	return 0;
 }
 
-struct list_head *coresight_build_path(struct coresight_device *csdev)
+struct list_head *coresight_build_path(struct coresight_device *source,
+				       struct coresight_device *sink)
 {
 	struct list_head *path;
 	int rc;
 
+	if (!sink)
+		return ERR_PTR(-EINVAL);
+
 	path = kzalloc(sizeof(struct list_head), GFP_KERNEL);
 	if (!path)
 		return ERR_PTR(-ENOMEM);
 
 	INIT_LIST_HEAD(path);
 
-	rc = _coresight_build_path(csdev, path);
+	rc = _coresight_build_path(source, sink, path);
 	if (rc) {
 		kfree(path);
 		return ERR_PTR(rc);
@@ -497,6 +548,7 @@ static int coresight_validate_source(struct coresight_device *csdev,
 int coresight_enable(struct coresight_device *csdev)
 {
 	int cpu, ret = 0;
+	struct coresight_device *sink;
 	struct list_head *path;
 
 	mutex_lock(&coresight_mutex);
@@ -508,7 +560,17 @@ int coresight_enable(struct coresight_device *csdev)
 	if (csdev->enable)
 		goto out;
 
-	path = coresight_build_path(csdev);
+	/*
+	 * Search for a valid sink for this session but don't reset the
+	 * "enable_sink" flag in sysFS.  Users get to do that explicitly.
+	 */
+	sink = coresight_get_enabled_sink(false);
+	if (!sink) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	path = coresight_build_path(csdev, sink);
 	if (IS_ERR(path)) {
 		pr_err("building path(s) failed\n");
 		ret = PTR_ERR(path);
-- 
2.7.4

[PATCH 5/8] coresight: tmc: Cleanup operation mode handling

[Mathieu Poirier]

From: "Suzuki K. Poulose" <Suzuki.Poulose@arm.com>

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>
---
 drivers/hwtracing/coresight/coresight-tmc-etf.c | 32 +++++++++++--------------
 drivers/hwtracing/coresight/coresight-tmc-etr.c | 26 +++++++++-----------
 drivers/hwtracing/coresight/coresight-tmc.h     |  2 +-
 3 files changed, 26 insertions(+), 34 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-tmc-etf.c b/drivers/hwtracing/coresight/coresight-tmc-etf.c
index d6941ea24d8d..e80a8f4cd12e 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etf.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etf.c
@@ -70,7 +70,7 @@ static void tmc_etb_disable_hw(struct tmc_drvdata *drvdata)
 	 * When operating in sysFS mode the content of the buffer needs to be
 	 * read before the TMC is disabled.
 	 */
-	if (local_read(&drvdata->mode) == CS_MODE_SYSFS)
+	if (drvdata->mode == CS_MODE_SYSFS)
 		tmc_etb_dump_hw(drvdata);
 	tmc_disable_hw(drvdata);
 
@@ -108,7 +108,6 @@ static int tmc_enable_etf_sink_sysfs(struct coresight_device *csdev, u32 mode)
 	int ret = 0;
 	bool used = false;
 	char *buf = NULL;
-	long val;
 	unsigned long flags;
 	struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
 
@@ -138,13 +137,12 @@ static int tmc_enable_etf_sink_sysfs(struct coresight_device *csdev, u32 mode)
 		goto out;
 	}
 
-	val = local_xchg(&drvdata->mode, mode);
 	/*
 	 * In sysFS mode we can have multiple writers per sink.  Since this
 	 * sink is already enabled no memory is needed and the HW need not be
 	 * touched.
 	 */
-	if (val == CS_MODE_SYSFS)
+	if (drvdata->mode == CS_MODE_SYSFS)
 		goto out;
 
 	/*
@@ -163,6 +161,7 @@ static int tmc_enable_etf_sink_sysfs(struct coresight_device *csdev, u32 mode)
 		drvdata->buf = buf;
 	}
 
+	drvdata->mode = CS_MODE_SYSFS;
 	tmc_etb_enable_hw(drvdata);
 out:
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
@@ -180,7 +179,6 @@ static int tmc_enable_etf_sink_sysfs(struct coresight_device *csdev, u32 mode)
 static int tmc_enable_etf_sink_perf(struct coresight_device *csdev, u32 mode)
 {
 	int ret = 0;
-	long val;
 	unsigned long flags;
 	struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
 
@@ -194,17 +192,17 @@ static int tmc_enable_etf_sink_perf(struct coresight_device *csdev, u32 mode)
 		goto out;
 	}
 
-	val = local_xchg(&drvdata->mode, mode);
 	/*
 	 * In Perf mode there can be only one writer per sink.  There
 	 * is also no need to continue if the ETB/ETR is already operated
 	 * from sysFS.
 	 */
-	if (val != CS_MODE_DISABLED) {
+	if (drvdata->mode != CS_MODE_DISABLED) {
 		ret = -EINVAL;
 		goto out;
 	}
 
+	drvdata->mode = mode;
 	tmc_etb_enable_hw(drvdata);
 out:
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
@@ -227,7 +225,6 @@ static int tmc_enable_etf_sink(struct coresight_device *csdev, u32 mode)
 
 static void tmc_disable_etf_sink(struct coresight_device *csdev)
 {
-	long val;
 	unsigned long flags;
 	struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
 
@@ -237,10 +234,11 @@ static void tmc_disable_etf_sink(struct coresight_device *csdev)
 		return;
 	}
 
-	val = local_xchg(&drvdata->mode, CS_MODE_DISABLED);
 	/* Disable the TMC only if it needs to */
-	if (val != CS_MODE_DISABLED)
+	if (drvdata->mode != CS_MODE_DISABLED) {
 		tmc_etb_disable_hw(drvdata);
+		drvdata->mode = CS_MODE_DISABLED;
+	}
 
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
 
@@ -260,7 +258,7 @@ static int tmc_enable_etf_link(struct coresight_device *csdev,
 	}
 
 	tmc_etf_enable_hw(drvdata);
-	local_set(&drvdata->mode, CS_MODE_SYSFS);
+	drvdata->mode = CS_MODE_SYSFS;
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
 
 	dev_info(drvdata->dev, "TMC-ETF enabled\n");
@@ -280,7 +278,7 @@ static void tmc_disable_etf_link(struct coresight_device *csdev,
 	}
 
 	tmc_etf_disable_hw(drvdata);
-	local_set(&drvdata->mode, CS_MODE_DISABLED);
+	drvdata->mode = CS_MODE_DISABLED;
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
 
 	dev_info(drvdata->dev, "TMC disabled\n");
@@ -383,7 +381,7 @@ static void tmc_update_etf_buffer(struct coresight_device *csdev,
 		return;
 
 	/* This shouldn't happen */
-	if (WARN_ON_ONCE(local_read(&drvdata->mode) != CS_MODE_PERF))
+	if (WARN_ON_ONCE(drvdata->mode != CS_MODE_PERF))
 		return;
 
 	CS_UNLOCK(drvdata->base);
@@ -504,7 +502,6 @@ const struct coresight_ops tmc_etf_cs_ops = {
 
 int tmc_read_prepare_etb(struct tmc_drvdata *drvdata)
 {
-	long val;
 	enum tmc_mode mode;
 	int ret = 0;
 	unsigned long flags;
@@ -528,9 +525,8 @@ int tmc_read_prepare_etb(struct tmc_drvdata *drvdata)
 		goto out;
 	}
 
-	val = local_read(&drvdata->mode);
 	/* Don't interfere if operated from Perf */
-	if (val == CS_MODE_PERF) {
+	if (drvdata->mode == CS_MODE_PERF) {
 		ret = -EINVAL;
 		goto out;
 	}
@@ -542,7 +538,7 @@ int tmc_read_prepare_etb(struct tmc_drvdata *drvdata)
 	}
 
 	/* Disable the TMC if need be */
-	if (val == CS_MODE_SYSFS)
+	if (drvdata->mode == CS_MODE_SYSFS)
 		tmc_etb_disable_hw(drvdata);
 
 	drvdata->reading = true;
@@ -573,7 +569,7 @@ int tmc_read_unprepare_etb(struct tmc_drvdata *drvdata)
 	}
 
 	/* Re-enable the TMC if need be */
-	if (local_read(&drvdata->mode) == CS_MODE_SYSFS) {
+	if (drvdata->mode == CS_MODE_SYSFS) {
 		/*
 		 * The trace run will continue with the same allocated trace
 		 * buffer. As such zero-out the buffer so that we don't end
diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
index 886ea83c68e0..f23ef0c23303 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
@@ -86,7 +86,7 @@ static void tmc_etr_disable_hw(struct tmc_drvdata *drvdata)
 	 * When operating in sysFS mode the content of the buffer needs to be
 	 * read before the TMC is disabled.
 	 */
-	if (local_read(&drvdata->mode) == CS_MODE_SYSFS)
+	if (drvdata->mode == CS_MODE_SYSFS)
 		tmc_etr_dump_hw(drvdata);
 	tmc_disable_hw(drvdata);
 
@@ -97,7 +97,6 @@ static int tmc_enable_etr_sink_sysfs(struct coresight_device *csdev, u32 mode)
 {
 	int ret = 0;
 	bool used = false;
-	long val;
 	unsigned long flags;
 	void __iomem *vaddr = NULL;
 	dma_addr_t paddr;
@@ -134,13 +133,12 @@ static int tmc_enable_etr_sink_sysfs(struct coresight_device *csdev, u32 mode)
 		goto out;
 	}
 
-	val = local_xchg(&drvdata->mode, mode);
 	/*
 	 * In sysFS mode we can have multiple writers per sink.  Since this
 	 * sink is already enabled no memory is needed and the HW need not be
 	 * touched.
 	 */
-	if (val == CS_MODE_SYSFS)
+	if (drvdata->mode == CS_MODE_SYSFS)
 		goto out;
 
 	/*
@@ -157,6 +155,7 @@ static int tmc_enable_etr_sink_sysfs(struct coresight_device *csdev, u32 mode)
 
 	memset(drvdata->vaddr, 0, drvdata->size);
 
+	drvdata->mode = CS_MODE_SYSFS;
 	tmc_etr_enable_hw(drvdata);
 out:
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
@@ -174,7 +173,6 @@ static int tmc_enable_etr_sink_sysfs(struct coresight_device *csdev, u32 mode)
 static int tmc_enable_etr_sink_perf(struct coresight_device *csdev, u32 mode)
 {
 	int ret = 0;
-	long val;
 	unsigned long flags;
 	struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
 
@@ -188,17 +186,17 @@ static int tmc_enable_etr_sink_perf(struct coresight_device *csdev, u32 mode)
 		goto out;
 	}
 
-	val = local_xchg(&drvdata->mode, mode);
 	/*
 	 * In Perf mode there can be only one writer per sink.  There
 	 * is also no need to continue if the ETR is already operated
 	 * from sysFS.
 	 */
-	if (val != CS_MODE_DISABLED) {
+	if (drvdata->mode != CS_MODE_DISABLED) {
 		ret = -EINVAL;
 		goto out;
 	}
 
+	drvdata->mode = CS_MODE_PERF;
 	tmc_etr_enable_hw(drvdata);
 out:
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
@@ -221,7 +219,6 @@ static int tmc_enable_etr_sink(struct coresight_device *csdev, u32 mode)
 
 static void tmc_disable_etr_sink(struct coresight_device *csdev)
 {
-	long val;
 	unsigned long flags;
 	struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
 
@@ -231,10 +228,11 @@ static void tmc_disable_etr_sink(struct coresight_device *csdev)
 		return;
 	}
 
-	val = local_xchg(&drvdata->mode, CS_MODE_DISABLED);
 	/* Disable the TMC only if it needs to */
-	if (val != CS_MODE_DISABLED)
+	if (drvdata->mode != CS_MODE_DISABLED) {
 		tmc_etr_disable_hw(drvdata);
+		drvdata->mode = CS_MODE_DISABLED;
+	}
 
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
 
@@ -253,7 +251,6 @@ const struct coresight_ops tmc_etr_cs_ops = {
 int tmc_read_prepare_etr(struct tmc_drvdata *drvdata)
 {
 	int ret = 0;
-	long val;
 	unsigned long flags;
 
 	/* config types are set a boot time and never change */
@@ -266,9 +263,8 @@ int tmc_read_prepare_etr(struct tmc_drvdata *drvdata)
 		goto out;
 	}
 
-	val = local_read(&drvdata->mode);
 	/* Don't interfere if operated from Perf */
-	if (val == CS_MODE_PERF) {
+	if (drvdata->mode == CS_MODE_PERF) {
 		ret = -EINVAL;
 		goto out;
 	}
@@ -280,7 +276,7 @@ int tmc_read_prepare_etr(struct tmc_drvdata *drvdata)
 	}
 
 	/* Disable the TMC if need be */
-	if (val == CS_MODE_SYSFS)
+	if (drvdata->mode == CS_MODE_SYSFS)
 		tmc_etr_disable_hw(drvdata);
 
 	drvdata->reading = true;
@@ -303,7 +299,7 @@ int tmc_read_unprepare_etr(struct tmc_drvdata *drvdata)
 	spin_lock_irqsave(&drvdata->spinlock, flags);
 
 	/* RE-enable the TMC if need be */
-	if (local_read(&drvdata->mode) == CS_MODE_SYSFS) {
+	if (drvdata->mode == CS_MODE_SYSFS) {
 		/*
 		 * The trace run will continue with the same allocated trace
 		 * buffer. The trace buffer is cleared in tmc_etr_enable_hw(),
diff --git a/drivers/hwtracing/coresight/coresight-tmc.h b/drivers/hwtracing/coresight/coresight-tmc.h
index 44b3ae346118..51c01851533e 100644
--- a/drivers/hwtracing/coresight/coresight-tmc.h
+++ b/drivers/hwtracing/coresight/coresight-tmc.h
@@ -117,7 +117,7 @@ struct tmc_drvdata {
 	void __iomem		*vaddr;
 	u32			size;
 	u32			len;
-	local_t			mode;
+	u32			mode;
 	enum tmc_config_type	config_type;
 	enum tmc_mem_intf_width	memwidth;
 	u32			trigger_cntr;
-- 
2.7.4

[PATCH 6/8] coresight: tmc: Get rid of mode parameter for helper routines

[Mathieu Poirier]

From: "Suzuki K. Poulose" <Suzuki.Poulose@arm.com>

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>
---
 drivers/hwtracing/coresight/coresight-tmc-etf.c | 18 +++++-------------
 drivers/hwtracing/coresight/coresight-tmc-etr.c | 15 ++++-----------
 2 files changed, 9 insertions(+), 24 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-tmc-etf.c b/drivers/hwtracing/coresight/coresight-tmc-etf.c
index e80a8f4cd12e..1549436e2492 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etf.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etf.c
@@ -103,7 +103,7 @@ static void tmc_etf_disable_hw(struct tmc_drvdata *drvdata)
 	CS_LOCK(drvdata->base);
 }
 
-static int tmc_enable_etf_sink_sysfs(struct coresight_device *csdev, u32 mode)
+static int tmc_enable_etf_sink_sysfs(struct coresight_device *csdev)
 {
 	int ret = 0;
 	bool used = false;
@@ -111,10 +111,6 @@ static int tmc_enable_etf_sink_sysfs(struct coresight_device *csdev, u32 mode)
 	unsigned long flags;
 	struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
 
-	 /* This shouldn't be happening */
-	if (WARN_ON(mode != CS_MODE_SYSFS))
-		return -EINVAL;
-
 	/*
 	 * If we don't have a buffer release the lock and allocate memory.
 	 * Otherwise keep the lock and move along.
@@ -176,16 +172,12 @@ static int tmc_enable_etf_sink_sysfs(struct coresight_device *csdev, u32 mode)
 	return ret;
 }
 
-static int tmc_enable_etf_sink_perf(struct coresight_device *csdev, u32 mode)
+static int tmc_enable_etf_sink_perf(struct coresight_device *csdev)
 {
 	int ret = 0;
 	unsigned long flags;
 	struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
 
-	 /* This shouldn't be happening */
-	if (WARN_ON(mode != CS_MODE_PERF))
-		return -EINVAL;
-
 	spin_lock_irqsave(&drvdata->spinlock, flags);
 	if (drvdata->reading) {
 		ret = -EINVAL;
@@ -202,7 +194,7 @@ static int tmc_enable_etf_sink_perf(struct coresight_device *csdev, u32 mode)
 		goto out;
 	}
 
-	drvdata->mode = mode;
+	drvdata->mode = CS_MODE_PERF;
 	tmc_etb_enable_hw(drvdata);
 out:
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
@@ -214,9 +206,9 @@ static int tmc_enable_etf_sink(struct coresight_device *csdev, u32 mode)
 {
 	switch (mode) {
 	case CS_MODE_SYSFS:
-		return tmc_enable_etf_sink_sysfs(csdev, mode);
+		return tmc_enable_etf_sink_sysfs(csdev);
 	case CS_MODE_PERF:
-		return tmc_enable_etf_sink_perf(csdev, mode);
+		return tmc_enable_etf_sink_perf(csdev);
 	}
 
 	/* We shouldn't be here */
diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
index f23ef0c23303..3b84d0d38c22 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
@@ -93,7 +93,7 @@ static void tmc_etr_disable_hw(struct tmc_drvdata *drvdata)
 	CS_LOCK(drvdata->base);
 }
 
-static int tmc_enable_etr_sink_sysfs(struct coresight_device *csdev, u32 mode)
+static int tmc_enable_etr_sink_sysfs(struct coresight_device *csdev)
 {
 	int ret = 0;
 	bool used = false;
@@ -102,9 +102,6 @@ static int tmc_enable_etr_sink_sysfs(struct coresight_device *csdev, u32 mode)
 	dma_addr_t paddr;
 	struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
 
-	 /* This shouldn't be happening */
-	if (WARN_ON(mode != CS_MODE_SYSFS))
-		return -EINVAL;
 
 	/*
 	 * If we don't have a buffer release the lock and allocate memory.
@@ -170,16 +167,12 @@ static int tmc_enable_etr_sink_sysfs(struct coresight_device *csdev, u32 mode)
 	return ret;
 }
 
-static int tmc_enable_etr_sink_perf(struct coresight_device *csdev, u32 mode)
+static int tmc_enable_etr_sink_perf(struct coresight_device *csdev)
 {
 	int ret = 0;
 	unsigned long flags;
 	struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
 
-	 /* This shouldn't be happening */
-	if (WARN_ON(mode != CS_MODE_PERF))
-		return -EINVAL;
-
 	spin_lock_irqsave(&drvdata->spinlock, flags);
 	if (drvdata->reading) {
 		ret = -EINVAL;
@@ -208,9 +201,9 @@ static int tmc_enable_etr_sink(struct coresight_device *csdev, u32 mode)
 {
 	switch (mode) {
 	case CS_MODE_SYSFS:
-		return tmc_enable_etr_sink_sysfs(csdev, mode);
+		return tmc_enable_etr_sink_sysfs(csdev);
 	case CS_MODE_PERF:
-		return tmc_enable_etr_sink_perf(csdev, mode);
+		return tmc_enable_etr_sink_perf(csdev);
 	}
 
 	/* We shouldn't be here */
-- 
2.7.4

[PATCH 7/8] coresight: tmc: Remove duplicate memset

[Mathieu Poirier]

From: "Suzuki K. Poulose" <Suzuki.Poulose@arm.com>

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>
---
 drivers/hwtracing/coresight/coresight-tmc-etr.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
index 3b84d0d38c22..5d312699b3b9 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
@@ -150,8 +150,6 @@ static int tmc_enable_etr_sink_sysfs(struct coresight_device *csdev)
 		drvdata->buf = drvdata->vaddr;
 	}
 
-	memset(drvdata->vaddr, 0, drvdata->size);
-
 	drvdata->mode = CS_MODE_SYSFS;
 	tmc_etr_enable_hw(drvdata);
 out:
-- 
2.7.4

[PATCH 8/8] coresight: Add support for ARM Coresight STM-500

[Mathieu Poirier]

From: Suzuki K Poulose <suzuki.poulose@arm.com>

Add the PIDs for STM-500 to the known STM devices list.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Chunyan Zhang <zhang.chunyan@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
 drivers/hwtracing/coresight/coresight-stm.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/hwtracing/coresight/coresight-stm.c b/drivers/hwtracing/coresight/coresight-stm.c
index d397849c2c6a..944c17b48d23 100644
--- a/drivers/hwtracing/coresight/coresight-stm.c
+++ b/drivers/hwtracing/coresight/coresight-stm.c
@@ -920,6 +920,11 @@ static struct amba_id stm_ids[] = {
 		.mask   = 0x0003ffff,
 		.data	= "STM32",
 	},
+	{
+		.id	= 0x0003b963,
+		.mask	= 0x0003ffff,
+		.data	= "STM500",
+	},
 	{ 0, 0},
 };
 
-- 
2.7.4