[PATCH 00/44] coresight: next v4.19-rc4

[PATCH 00/44] coresight: next v4.19-rc4

[Mathieu Poirier]

Good day Greg,

To start with here is the tally I gathered for inclusion in the 4.20
cycle - please consider at your convenience.  As usual everything applies
cleanly on your char-misc-next branch (f685fc6ab051).

Second, given the increasing number of patches coming into the coresight
subsystem and your new reponsabilities, I was wondering if you'd rather receive
a pull request from hereon.  Let me know what works best for you.

Cordially,
Mathieu 


Leo Yan (2):
  coresight: tmc: Refactor loops in etb dump
  coresight: tmc: Fix byte-address alignment for RRP

Mathieu Poirier (2):
  coresight: etb10: Refactor etb_drvdata::mode handling
  coresight: etb10: Splitting function etb_enable()

Suzuki K Poulose (37):
  coresight: Document error handling in coresight_register
  coresight: platform: Refactor graph endpoint parsing
  coresight: platform: Fix refcounting for graph nodes
  coresight: platform: Fix leaking device reference
  coresight: Fix remote endpoint parsing
  coresight: Add helper to check if the endpoint is input
  coresight: platform: Cleanup coresight connection handling
  coresight: Cleanup coresight DT bindings
  coresight: Fix handling of sinks
  coresight: etb10: Fix handling of perf mode
  coresight: perf: Fix per cpu path management
  coresight: perf: Avoid unncessary CPU hotplug read lock
  coresight: perf: Allow tracing on hotplugged CPUs
  coresight: perf: Disable trace path upon source error
  coresight: tmc-etr: Handle driver mode specific ETR buffers
  coresight: tmc-etr: Relax collection of trace from sysfs mode
  coresight: Convert driver messages to dev_dbg
  coresight: perf: Remove reset_buffer call back for sinks
  coresight: perf: Add helper to retrieve sink configuration
  coresight: perf: Remove set_buffer call back
  coresight: etm-perf: Add support for ETR backend
  coresight: Handle failures in enabling a trace path
  coresight: tmc-etr: Refactor for handling errors
  coresight: tmc-etr: Handle errors enabling CATU
  coresight: tmc-etb/etf: Prepare to handle errors enabling
  coresight: etm4x: Add support for handling errors
  coresight: etm3: Add support for handling errors
  coresight: etb10: Handle errors enabling the device
  coresight: dynamic-replicator: Handle multiple connections
  coresight: Add support for CLAIM tag protocol
  coresight: etmx: Claim devices before use
  coresight: funnel: Claim devices before use
  coresight: catu: Claim device before use
  coresight: dynamic-replicator: Claim device for use
  coreisght: tmc: Claim device before use
  coresight: dts: binding: Fix example for TPIU component
  coresight: dts: binding: Update coresight binding examples

Tomasz Nowicki (1):
  coresight: etm4x: Configure EL2 exception level when kernel is running
    in HYP

zhong jiang (2):
  coresight: Use ERR_CAST instead of ERR_PTR
  coresight: Remove redundant null pointer check before of_node_put and
    put_device

 .../devicetree/bindings/arm/coresight.txt          | 120 ++++---
 drivers/hwtracing/coresight/coresight-catu.c       |   6 +
 .../coresight/coresight-dynamic-replicator.c       |  81 ++++-
 drivers/hwtracing/coresight/coresight-etb10.c      | 183 ++++++----
 drivers/hwtracing/coresight/coresight-etm-perf.c   | 132 +++----
 drivers/hwtracing/coresight/coresight-etm-perf.h   |  26 ++
 drivers/hwtracing/coresight/coresight-etm3x.c      |  58 +++-
 drivers/hwtracing/coresight/coresight-etm4x.c      |  93 +++--
 drivers/hwtracing/coresight/coresight-funnel.c     |  28 +-
 drivers/hwtracing/coresight/coresight-priv.h       |   9 +-
 drivers/hwtracing/coresight/coresight-replicator.c |   4 +-
 drivers/hwtracing/coresight/coresight-stm.c        |   4 +-
 drivers/hwtracing/coresight/coresight-tmc-etf.c    | 198 ++++++-----
 drivers/hwtracing/coresight/coresight-tmc-etr.c    | 385 ++++++++++++++++++---
 drivers/hwtracing/coresight/coresight-tmc.c        |   4 +-
 drivers/hwtracing/coresight/coresight-tmc.h        |   4 +
 drivers/hwtracing/coresight/coresight-tpiu.c       |   6 +-
 drivers/hwtracing/coresight/coresight.c            | 184 +++++++---
 drivers/hwtracing/coresight/of_coresight.c         | 262 +++++++++-----
 include/linux/coresight.h                          |  41 ++-
 20 files changed, 1268 insertions(+), 560 deletions(-)

-- 
2.7.4

[PATCH 01/44] coresight: Document error handling in coresight_register

[Mathieu Poirier]

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

commit 6403587a930c ("coresight: use put_device() instead of kfree()")
fixes the double freeing of resources and ensures that the device
refcount is dropped properly. Add a comment to explain this to
help the readers and prevent people trying to "unfix" it again.

While at it, rename the labels for better readability.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
 drivers/hwtracing/coresight/coresight.c | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight.c b/drivers/hwtracing/coresight/coresight.c
index 3e07fd335f8c..9fd0c387e678 100644
--- a/drivers/hwtracing/coresight/coresight.c
+++ b/drivers/hwtracing/coresight/coresight.c
@@ -1006,7 +1006,7 @@ struct coresight_device *coresight_register(struct coresight_desc *desc)
 	csdev = kzalloc(sizeof(*csdev), GFP_KERNEL);
 	if (!csdev) {
 		ret = -ENOMEM;
-		goto err_kzalloc_csdev;
+		goto err_out;
 	}
 
 	if (desc->type == CORESIGHT_DEV_TYPE_LINK ||
@@ -1022,7 +1022,7 @@ struct coresight_device *coresight_register(struct coresight_desc *desc)
 	refcnts = kcalloc(nr_refcnts, sizeof(*refcnts), GFP_KERNEL);
 	if (!refcnts) {
 		ret = -ENOMEM;
-		goto err_kzalloc_refcnts;
+		goto err_free_csdev;
 	}
 
 	csdev->refcnt = refcnts;
@@ -1035,7 +1035,7 @@ struct coresight_device *coresight_register(struct coresight_desc *desc)
 		conns = kcalloc(csdev->nr_outport, sizeof(*conns), GFP_KERNEL);
 		if (!conns) {
 			ret = -ENOMEM;
-			goto err_kzalloc_conns;
+			goto err_free_refcnts;
 		}
 
 		for (i = 0; i < csdev->nr_outport; i++) {
@@ -1062,7 +1062,11 @@ struct coresight_device *coresight_register(struct coresight_desc *desc)
 	ret = device_register(&csdev->dev);
 	if (ret) {
 		put_device(&csdev->dev);
-		goto err_kzalloc_csdev;
+		/*
+		 * All resources are free'd explicitly via
+		 * coresight_device_release(), triggered from put_device().
+		 */
+		goto err_out;
 	}
 
 	mutex_lock(&coresight_mutex);
@@ -1074,11 +1078,11 @@ struct coresight_device *coresight_register(struct coresight_desc *desc)
 
 	return csdev;
 
-err_kzalloc_conns:
+err_free_refcnts:
 	kfree(refcnts);
-err_kzalloc_refcnts:
+err_free_csdev:
 	kfree(csdev);
-err_kzalloc_csdev:
+err_out:
 	return ERR_PTR(ret);
 }
 EXPORT_SYMBOL_GPL(coresight_register);
-- 
2.7.4

[PATCH 02/44] coresight: platform: Refactor graph endpoint parsing

[Mathieu Poirier]

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

Refactor the of graph endpoint parsing code, to make the error
handling easier.

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/of_coresight.c | 138 +++++++++++++++++------------
 1 file changed, 83 insertions(+), 55 deletions(-)

diff --git a/drivers/hwtracing/coresight/of_coresight.c b/drivers/hwtracing/coresight/of_coresight.c
index 6880bee195c8..70205f3eae8e 100644
--- a/drivers/hwtracing/coresight/of_coresight.c
+++ b/drivers/hwtracing/coresight/of_coresight.c
@@ -114,17 +114,70 @@ int of_coresight_get_cpu(const struct device_node *node)
 }
 EXPORT_SYMBOL_GPL(of_coresight_get_cpu);
 
+/*
+ * of_coresight_parse_endpoint : Parse the given output endpoint @ep
+ * and fill the connection information in @pdata[@i].
+ *
+ * Parses the local port, remote device name and the remote port.
+ *
+ * Returns :
+ *	 1	- If the parsing is successful and a connection record
+ *		  was created for an output connection.
+ *	 0	- If the parsing completed without any fatal errors.
+ *	-Errno	- Fatal error, abort the scanning.
+ */
+static int of_coresight_parse_endpoint(struct device *dev,
+				       struct device_node *ep,
+				       struct coresight_platform_data *pdata,
+				       int i)
+{
+	int ret = 0;
+	struct of_endpoint endpoint, rendpoint;
+	struct device_node *rparent = NULL;
+	struct device_node *rport = NULL;
+	struct device *rdev = NULL;
+
+	do {
+		/* Parse the local port details */
+		if (of_graph_parse_endpoint(ep, &endpoint))
+			break;
+		/*
+		 * Get a handle on the remote port and parent
+		 * attached to it.
+		 */
+		rparent = of_graph_get_remote_port_parent(ep);
+		if (!rparent)
+			break;
+		rport = of_graph_get_remote_port(ep);
+		if (!rport)
+			break;
+		if (of_graph_parse_endpoint(rport, &rendpoint))
+			break;
+
+		/* If the remote device is not available, defer probing */
+		rdev = of_coresight_get_endpoint_device(rparent);
+		if (!rdev) {
+			ret = -EPROBE_DEFER;
+			break;
+		}
+
+		pdata->outports[i] = endpoint.port;
+		pdata->child_names[i] = dev_name(rdev);
+		pdata->child_ports[i] = rendpoint.id;
+		/* Connection record updated */
+		ret = 1;
+	} while (0);
+
+	return ret;
+}
+
 struct coresight_platform_data *
 of_get_coresight_platform_data(struct device *dev,
 			       const struct device_node *node)
 {
 	int i = 0, ret = 0;
 	struct coresight_platform_data *pdata;
-	struct of_endpoint endpoint, rendpoint;
-	struct device *rdev;
 	struct device_node *ep = NULL;
-	struct device_node *rparent = NULL;
-	struct device_node *rport = NULL;
 
 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
 	if (!pdata)
@@ -132,64 +185,39 @@ of_get_coresight_platform_data(struct device *dev,
 
 	/* Use device name as sysfs handle */
 	pdata->name = dev_name(dev);
+	pdata->cpu = of_coresight_get_cpu(node);
 
 	/* Get the number of input and output port for this component */
 	of_coresight_get_ports(node, &pdata->nr_inport, &pdata->nr_outport);
 
-	if (pdata->nr_outport) {
-		ret = of_coresight_alloc_memory(dev, pdata);
-		if (ret)
+	/* If there are no output connections, we are done */
+	if (!pdata->nr_outport)
+		return pdata;
+
+	ret = of_coresight_alloc_memory(dev, pdata);
+	if (ret)
+		return ERR_PTR(ret);
+
+	/* Iterate through each port to discover topology */
+	while ((ep = of_graph_get_next_endpoint(node, ep))) {
+		/*
+		 * No need to deal with input ports, as processing the
+		 * output ports connected to them will process the details.
+		 */
+		if (of_find_property(ep, "slave-mode", NULL))
+			continue;
+
+		ret = of_coresight_parse_endpoint(dev, ep, pdata, i);
+		switch (ret) {
+		case 1:
+			i++;		/* Fall through */
+		case 0:
+			break;
+		default:
 			return ERR_PTR(ret);
-
-		/* Iterate through each port to discover topology */
-		do {
-			/* Get a handle on a port */
-			ep = of_graph_get_next_endpoint(node, ep);
-			if (!ep)
-				break;
-
-			/*
-			 * No need to deal with input ports, processing for as
-			 * processing for output ports will deal with them.
-			 */
-			if (of_find_property(ep, "slave-mode", NULL))
-				continue;
-
-			/* Get a handle on the local endpoint */
-			ret = of_graph_parse_endpoint(ep, &endpoint);
-
-			if (ret)
-				continue;
-
-			/* The local out port number */
-			pdata->outports[i] = endpoint.port;
-
-			/*
-			 * Get a handle on the remote port and parent
-			 * attached to it.
-			 */
-			rparent = of_graph_get_remote_port_parent(ep);
-			rport = of_graph_get_remote_port(ep);
-
-			if (!rparent || !rport)
-				continue;
-
-			if (of_graph_parse_endpoint(rport, &rendpoint))
-				continue;
-
-			rdev = of_coresight_get_endpoint_device(rparent);
-			if (!rdev)
-				return ERR_PTR(-EPROBE_DEFER);
-
-			pdata->child_names[i] = dev_name(rdev);
-			pdata->child_ports[i] = rendpoint.id;
-
-			i++;
-		} while (ep);
+		}
 	}
 
-	pdata->cpu = of_coresight_get_cpu(node);
-
 	return pdata;
 }
 EXPORT_SYMBOL_GPL(of_get_coresight_platform_data);
-- 
2.7.4

[PATCH 03/44] coresight: platform: Fix refcounting for graph nodes

[Mathieu Poirier]

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

The coresight driver doesn't drop the references on the
remote endpoint/port nodes. Add the missing of_node_put()
calls.

Reported-by: 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/of_coresight.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/hwtracing/coresight/of_coresight.c b/drivers/hwtracing/coresight/of_coresight.c
index 70205f3eae8e..28d3aef1660b 100644
--- a/drivers/hwtracing/coresight/of_coresight.c
+++ b/drivers/hwtracing/coresight/of_coresight.c
@@ -168,6 +168,11 @@ static int of_coresight_parse_endpoint(struct device *dev,
 		ret = 1;
 	} while (0);
 
+	if (rparent)
+		of_node_put(rparent);
+	if (rport)
+		of_node_put(rport);
+
 	return ret;
 }
 
-- 
2.7.4

[PATCH 04/44] coresight: platform: Fix leaking device reference

[Mathieu Poirier]

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

We don't drop the reference on the remote device while parsing the
connection, held by bus_find_device(). Fix this by duplicating the
device name and dropping the reference.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Kim Phillips <kim.phillips@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
 drivers/hwtracing/coresight/of_coresight.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/hwtracing/coresight/of_coresight.c b/drivers/hwtracing/coresight/of_coresight.c
index 28d3aef1660b..4b279f8fea0c 100644
--- a/drivers/hwtracing/coresight/of_coresight.c
+++ b/drivers/hwtracing/coresight/of_coresight.c
@@ -162,7 +162,9 @@ static int of_coresight_parse_endpoint(struct device *dev,
 		}
 
 		pdata->outports[i] = endpoint.port;
-		pdata->child_names[i] = dev_name(rdev);
+		pdata->child_names[i] = devm_kstrdup(dev,
+						     dev_name(rdev),
+						     GFP_KERNEL);
 		pdata->child_ports[i] = rendpoint.id;
 		/* Connection record updated */
 		ret = 1;
@@ -172,6 +174,8 @@ static int of_coresight_parse_endpoint(struct device *dev,
 		of_node_put(rparent);
 	if (rport)
 		of_node_put(rport);
+	if (rdev)
+		put_device(rdev);
 
 	return ret;
 }
-- 
2.7.4

[PATCH 05/44] coresight: Fix remote endpoint parsing

[Mathieu Poirier]

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

When parsing the remote endpoint of an output port, we do :
     rport = of_graph_get_remote_port(ep);
     rparent = of_graph_get_remote_port_parent(ep);

and then parse the "remote_port" as if it was the remote endpoint,
which is wrong. The code worked fine because we used endpoint number
as the port number. Let us fix it and optimise a bit as:

     remote_ep = of_graph_get_remote_endpoint(ep);
     if (remote_ep)
        remote_parent = of_graph_get_port_parent(remote_ep);

and then, parse the remote_ep for the port/endpoint details.

Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
 drivers/hwtracing/coresight/of_coresight.c | 22 +++++++++++-----------
 1 file changed, 11 insertions(+), 11 deletions(-)

diff --git a/drivers/hwtracing/coresight/of_coresight.c b/drivers/hwtracing/coresight/of_coresight.c
index 4b279f8fea0c..2ecdd1432b5c 100644
--- a/drivers/hwtracing/coresight/of_coresight.c
+++ b/drivers/hwtracing/coresight/of_coresight.c
@@ -134,7 +134,7 @@ static int of_coresight_parse_endpoint(struct device *dev,
 	int ret = 0;
 	struct of_endpoint endpoint, rendpoint;
 	struct device_node *rparent = NULL;
-	struct device_node *rport = NULL;
+	struct device_node *rep = NULL;
 	struct device *rdev = NULL;
 
 	do {
@@ -142,16 +142,16 @@ static int of_coresight_parse_endpoint(struct device *dev,
 		if (of_graph_parse_endpoint(ep, &endpoint))
 			break;
 		/*
-		 * Get a handle on the remote port and parent
-		 * attached to it.
+		 * Get a handle on the remote endpoint and the device it is
+		 * attached to.
 		 */
-		rparent = of_graph_get_remote_port_parent(ep);
-		if (!rparent)
+		rep = of_graph_get_remote_endpoint(ep);
+		if (!rep)
 			break;
-		rport = of_graph_get_remote_port(ep);
-		if (!rport)
+		rparent = of_graph_get_port_parent(rep);
+		if (!rparent)
 			break;
-		if (of_graph_parse_endpoint(rport, &rendpoint))
+		if (of_graph_parse_endpoint(rep, &rendpoint))
 			break;
 
 		/* If the remote device is not available, defer probing */
@@ -165,15 +165,15 @@ static int of_coresight_parse_endpoint(struct device *dev,
 		pdata->child_names[i] = devm_kstrdup(dev,
 						     dev_name(rdev),
 						     GFP_KERNEL);
-		pdata->child_ports[i] = rendpoint.id;
+		pdata->child_ports[i] = rendpoint.port;
 		/* Connection record updated */
 		ret = 1;
 	} while (0);
 
 	if (rparent)
 		of_node_put(rparent);
-	if (rport)
-		of_node_put(rport);
+	if (rep)
+		of_node_put(rep);
 	if (rdev)
 		put_device(rdev);
 
-- 
2.7.4

[PATCH 06/44] coresight: Add helper to check if the endpoint is input

[Mathieu Poirier]

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

Add a helper to check if the given endpoint is input.

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/of_coresight.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/hwtracing/coresight/of_coresight.c b/drivers/hwtracing/coresight/of_coresight.c
index 2ecdd1432b5c..44903d35009f 100644
--- a/drivers/hwtracing/coresight/of_coresight.c
+++ b/drivers/hwtracing/coresight/of_coresight.c
@@ -45,6 +45,11 @@ of_coresight_get_endpoint_device(struct device_node *endpoint)
 			       endpoint, of_dev_node_match);
 }
 
+static inline bool of_coresight_ep_is_input(struct device_node *ep)
+{
+	return of_property_read_bool(ep, "slave-mode");
+}
+
 static void of_coresight_get_ports(const struct device_node *node,
 				   int *nr_inport, int *nr_outport)
 {
@@ -56,7 +61,7 @@ static void of_coresight_get_ports(const struct device_node *node,
 		if (!ep)
 			break;
 
-		if (of_property_read_bool(ep, "slave-mode"))
+		if (of_coresight_ep_is_input(ep))
 			in++;
 		else
 			out++;
@@ -213,7 +218,7 @@ of_get_coresight_platform_data(struct device *dev,
 		 * No need to deal with input ports, as processing the
 		 * output ports connected to them will process the details.
 		 */
-		if (of_find_property(ep, "slave-mode", NULL))
+		if (of_coresight_ep_is_input(ep))
 			continue;
 
 		ret = of_coresight_parse_endpoint(dev, ep, pdata, i);
-- 
2.7.4

[PATCH 07/44] coresight: platform: Cleanup coresight connection handling

[Mathieu Poirier]

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

The platform code parses the component connections and populates
a platform-description of the output connections in arrays of fields
(which is never freed). This is later copied in the coresight_register
to a newly allocated area, represented by coresight_connection(s).

This patch cleans up the code dealing with connections by making
use of the "coresight_connection" structure right at the platform
code and lets the generic driver simply re-use information provided
by the platform.

Thus making it reader friendly as well as avoiding the wastage of
unused memory.

Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
 drivers/hwtracing/coresight/coresight.c    | 21 +-----------
 drivers/hwtracing/coresight/of_coresight.c | 53 +++++++++++-------------------
 include/linux/coresight.h                  |  9 ++---
 3 files changed, 22 insertions(+), 61 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight.c b/drivers/hwtracing/coresight/coresight.c
index 9fd0c387e678..5e8880ca8078 100644
--- a/drivers/hwtracing/coresight/coresight.c
+++ b/drivers/hwtracing/coresight/coresight.c
@@ -995,13 +995,11 @@ postcore_initcall(coresight_init);
 
 struct coresight_device *coresight_register(struct coresight_desc *desc)
 {
-	int i;
 	int ret;
 	int link_subtype;
 	int nr_refcnts = 1;
 	atomic_t *refcnts = NULL;
 	struct coresight_device *csdev;
-	struct coresight_connection *conns = NULL;
 
 	csdev = kzalloc(sizeof(*csdev), GFP_KERNEL);
 	if (!csdev) {
@@ -1030,22 +1028,7 @@ struct coresight_device *coresight_register(struct coresight_desc *desc)
 	csdev->nr_inport = desc->pdata->nr_inport;
 	csdev->nr_outport = desc->pdata->nr_outport;
 
-	/* Initialise connections if there is at least one outport */
-	if (csdev->nr_outport) {
-		conns = kcalloc(csdev->nr_outport, sizeof(*conns), GFP_KERNEL);
-		if (!conns) {
-			ret = -ENOMEM;
-			goto err_free_refcnts;
-		}
-
-		for (i = 0; i < csdev->nr_outport; i++) {
-			conns[i].outport = desc->pdata->outports[i];
-			conns[i].child_name = desc->pdata->child_names[i];
-			conns[i].child_port = desc->pdata->child_ports[i];
-		}
-	}
-
-	csdev->conns = conns;
+	csdev->conns = desc->pdata->conns;
 
 	csdev->type = desc->type;
 	csdev->subtype = desc->subtype;
@@ -1078,8 +1061,6 @@ struct coresight_device *coresight_register(struct coresight_desc *desc)
 
 	return csdev;
 
-err_free_refcnts:
-	kfree(refcnts);
 err_free_csdev:
 	kfree(csdev);
 err_out:
diff --git a/drivers/hwtracing/coresight/of_coresight.c b/drivers/hwtracing/coresight/of_coresight.c
index 44903d35009f..e8fb4e124744 100644
--- a/drivers/hwtracing/coresight/of_coresight.c
+++ b/drivers/hwtracing/coresight/of_coresight.c
@@ -75,29 +75,13 @@ static void of_coresight_get_ports(const struct device_node *node,
 static int of_coresight_alloc_memory(struct device *dev,
 			struct coresight_platform_data *pdata)
 {
-	/* List of output port on this component */
-	pdata->outports = devm_kcalloc(dev,
-				       pdata->nr_outport,
-				       sizeof(*pdata->outports),
-				       GFP_KERNEL);
-	if (!pdata->outports)
-		return -ENOMEM;
-
-	/* Children connected to this component via @outports */
-	pdata->child_names = devm_kcalloc(dev,
-					  pdata->nr_outport,
-					  sizeof(*pdata->child_names),
-					  GFP_KERNEL);
-	if (!pdata->child_names)
-		return -ENOMEM;
-
-	/* Port number on the child this component is connected to */
-	pdata->child_ports = devm_kcalloc(dev,
-					  pdata->nr_outport,
-					  sizeof(*pdata->child_ports),
-					  GFP_KERNEL);
-	if (!pdata->child_ports)
-		return -ENOMEM;
+	if (pdata->nr_outport) {
+		pdata->conns = devm_kzalloc(dev, pdata->nr_outport *
+					    sizeof(*pdata->conns),
+					    GFP_KERNEL);
+		if (!pdata->conns)
+			return -ENOMEM;
+	}
 
 	return 0;
 }
@@ -121,7 +105,7 @@ EXPORT_SYMBOL_GPL(of_coresight_get_cpu);
 
 /*
  * of_coresight_parse_endpoint : Parse the given output endpoint @ep
- * and fill the connection information in @pdata[@i].
+ * and fill the connection information in @conn
  *
  * Parses the local port, remote device name and the remote port.
  *
@@ -133,8 +117,7 @@ EXPORT_SYMBOL_GPL(of_coresight_get_cpu);
  */
 static int of_coresight_parse_endpoint(struct device *dev,
 				       struct device_node *ep,
-				       struct coresight_platform_data *pdata,
-				       int i)
+				       struct coresight_connection *conn)
 {
 	int ret = 0;
 	struct of_endpoint endpoint, rendpoint;
@@ -166,11 +149,11 @@ static int of_coresight_parse_endpoint(struct device *dev,
 			break;
 		}
 
-		pdata->outports[i] = endpoint.port;
-		pdata->child_names[i] = devm_kstrdup(dev,
-						     dev_name(rdev),
-						     GFP_KERNEL);
-		pdata->child_ports[i] = rendpoint.port;
+		conn->outport = endpoint.port;
+		conn->child_name = devm_kstrdup(dev,
+						dev_name(rdev),
+						GFP_KERNEL);
+		conn->child_port = rendpoint.port;
 		/* Connection record updated */
 		ret = 1;
 	} while (0);
@@ -189,8 +172,9 @@ struct coresight_platform_data *
 of_get_coresight_platform_data(struct device *dev,
 			       const struct device_node *node)
 {
-	int i = 0, ret = 0;
+	int ret = 0;
 	struct coresight_platform_data *pdata;
+	struct coresight_connection *conn;
 	struct device_node *ep = NULL;
 
 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
@@ -212,6 +196,7 @@ of_get_coresight_platform_data(struct device *dev,
 	if (ret)
 		return ERR_PTR(ret);
 
+	conn = pdata->conns;
 	/* Iterate through each port to discover topology */
 	while ((ep = of_graph_get_next_endpoint(node, ep))) {
 		/*
@@ -221,10 +206,10 @@ of_get_coresight_platform_data(struct device *dev,
 		if (of_coresight_ep_is_input(ep))
 			continue;
 
-		ret = of_coresight_parse_endpoint(dev, ep, pdata, i);
+		ret = of_coresight_parse_endpoint(dev, ep, conn);
 		switch (ret) {
 		case 1:
-			i++;		/* Fall through */
+			conn++;		/* Fall through */
 		case 0:
 			break;
 		default:
diff --git a/include/linux/coresight.h b/include/linux/coresight.h
index d828a6efe0b1..41e1f4333bf2 100644
--- a/include/linux/coresight.h
+++ b/include/linux/coresight.h
@@ -94,20 +94,15 @@ union coresight_dev_subtype {
  * @cpu:	the CPU a source belongs to. Only applicable for ETM/PTMs.
  * @name:	name of the component as shown under sysfs.
  * @nr_inport:	number of input ports for this component.
- * @outports:	list of remote endpoint port number.
- * @child_names:name of all child components connected to this device.
- * @child_ports:child component port number the current component is
-		connected  to.
  * @nr_outport:	number of output ports for this component.
+ * @conns:	Array of nr_outport connections from this component
  */
 struct coresight_platform_data {
 	int cpu;
 	const char *name;
 	int nr_inport;
-	int *outports;
-	const char **child_names;
-	int *child_ports;
 	int nr_outport;
+	struct coresight_connection *conns;
 };
 
 /**
-- 
2.7.4

[PATCH 08/44] coresight: Cleanup coresight DT bindings

[Mathieu Poirier]

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

The coresight drivers relied on default bindings for graph
in DT, while reusing the "reg" field of the "ports" to indicate
the actual hardware port number for the connections. This can
cause duplicate ports with same addresses, but different
direction. However, with the rules getting stricter for the
address mismatch with the label, it is no longer possible to use
the port address field for the hardware port number.

This patch introduces new DT binding rules for coresight
components, based on the same generic DT graph bindings, but
avoiding the address duplication.

- All output ports must be specified under a child node with
  name "out-ports".
- All input ports must be specified under a childe node with
  name "in-ports".
- Port address should match the hardware port number.

The support for legacy bindings is retained, with a warning.

Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Rob Herring <robh@kernel.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
 .../devicetree/bindings/arm/coresight.txt          | 95 ++++++++++++---------
 drivers/hwtracing/coresight/of_coresight.c         | 98 +++++++++++++++++++---
 2 files changed, 143 insertions(+), 50 deletions(-)

diff --git a/Documentation/devicetree/bindings/arm/coresight.txt b/Documentation/devicetree/bindings/arm/coresight.txt
index 5d1ad09bafb4..f39d2c6eb49c 100644
--- a/Documentation/devicetree/bindings/arm/coresight.txt
+++ b/Documentation/devicetree/bindings/arm/coresight.txt
@@ -54,9 +54,7 @@ its hardware characteristcs.
 	  clocks the core of that coresight component. The latter clock
 	  is optional.
 
-	* port or ports: The representation of the component's port
-	  layout using the generic DT graph presentation found in
-	  "bindings/graph.txt".
+	* port or ports: see "Graph bindings for Coresight" below.
 
 * Additional required properties for System Trace Macrocells (STM):
 	* reg: along with the physical base address and length of the register
@@ -73,7 +71,7 @@ its hardware characteristcs.
 	  AMBA markee):
 		- "arm,coresight-replicator"
 
-	* port or ports: same as above.
+	* port or ports: see "Graph bindings for Coresight" below.
 
 * Optional properties for ETM/PTMs:
 
@@ -96,6 +94,20 @@ its hardware characteristcs.
 	* interrupts : Exactly one SPI may be listed for reporting the address
 	  error
 
+Graph bindings for Coresight
+-------------------------------
+
+Coresight components are interconnected to create a data path for the flow of
+trace data generated from the "sources" to their collection points "sink".
+Each coresight component must describe the "input" and "output" connections.
+The connections must be described via generic DT graph bindings as described
+by the "bindings/graph.txt", where each "port" along with an "endpoint"
+component represents a hardware port and the connection.
+
+ * All output ports must be listed inside a child node named "out-ports"
+ * All input ports must be listed inside a child node named "in-ports".
+ * Port address must match the hardware port number.
+
 Example:
 
 1. Sinks
@@ -105,10 +117,11 @@ Example:
 
 		clocks = <&oscclk6a>;
 		clock-names = "apb_pclk";
-		port {
-			etb_in_port: endpoint@0 {
-				slave-mode;
-				remote-endpoint = <&replicator_out_port0>;
+		in-ports {
+			port {
+				etb_in_port: endpoint@0 {
+					remote-endpoint = <&replicator_out_port0>;
+				};
 			};
 		};
 	};
@@ -119,10 +132,11 @@ Example:
 
 		clocks = <&oscclk6a>;
 		clock-names = "apb_pclk";
-		port {
-			tpiu_in_port: endpoint@0 {
-				slave-mode;
-				remote-endpoint = <&replicator_out_port1>;
+		out-ports {
+			port {
+				tpiu_in_port: endpoint@0 {
+					remote-endpoint = <&replicator_out_port1>;
+				};
 			};
 		};
 	};
@@ -163,7 +177,7 @@ Example:
 		 */
 		compatible = "arm,coresight-replicator";
 
-		ports {
+		out-ports {
 			#address-cells = <1>;
 			#size-cells = <0>;
 
@@ -181,12 +195,11 @@ Example:
 					remote-endpoint = <&tpiu_in_port>;
 				};
 			};
+		};
 
-			/* replicator input port */
-			port@2 {
-				reg = <0>;
+		in-ports {
+			port {
 				replicator_in_port0: endpoint {
-					slave-mode;
 					remote-endpoint = <&funnel_out_port0>;
 				};
 			};
@@ -199,40 +212,36 @@ Example:
 
 		clocks = <&oscclk6a>;
 		clock-names = "apb_pclk";
-		ports {
-			#address-cells = <1>;
-			#size-cells = <0>;
-
-			/* funnel output port */
-			port@0 {
-				reg = <0>;
+		out-ports {
+			port {
 				funnel_out_port0: endpoint {
 					remote-endpoint =
 							<&replicator_in_port0>;
 				};
 			};
+		};
 
-			/* funnel input ports */
-			port@1 {
+		in-ports {
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			port@0 {
 				reg = <0>;
 				funnel_in_port0: endpoint {
-					slave-mode;
 					remote-endpoint = <&ptm0_out_port>;
 				};
 			};
 
-			port@2 {
+			port@1 {
 				reg = <1>;
 				funnel_in_port1: endpoint {
-					slave-mode;
 					remote-endpoint = <&ptm1_out_port>;
 				};
 			};
 
-			port@3 {
+			port@2 {
 				reg = <2>;
 				funnel_in_port2: endpoint {
-					slave-mode;
 					remote-endpoint = <&etm0_out_port>;
 				};
 			};
@@ -248,9 +257,11 @@ Example:
 		cpu = <&cpu0>;
 		clocks = <&oscclk6a>;
 		clock-names = "apb_pclk";
-		port {
-			ptm0_out_port: endpoint {
-				remote-endpoint = <&funnel_in_port0>;
+		out-ports {
+			port {
+				ptm0_out_port: endpoint {
+					remote-endpoint = <&funnel_in_port0>;
+				};
 			};
 		};
 	};
@@ -262,9 +273,11 @@ Example:
 		cpu = <&cpu1>;
 		clocks = <&oscclk6a>;
 		clock-names = "apb_pclk";
-		port {
-			ptm1_out_port: endpoint {
-				remote-endpoint = <&funnel_in_port1>;
+		out-ports {
+			port {
+				ptm1_out_port: endpoint {
+					remote-endpoint = <&funnel_in_port1>;
+				};
 			};
 		};
 	};
@@ -278,9 +291,11 @@ Example:
 
 		clocks = <&soc_smc50mhz>;
 		clock-names = "apb_pclk";
-		port {
-			stm_out_port: endpoint {
-				remote-endpoint = <&main_funnel_in_port2>;
+		out-ports {
+			port {
+				stm_out_port: endpoint {
+					remote-endpoint = <&main_funnel_in_port2>;
+				};
 			};
 		};
 	};
diff --git a/drivers/hwtracing/coresight/of_coresight.c b/drivers/hwtracing/coresight/of_coresight.c
index e8fb4e124744..da71c975e3f7 100644
--- a/drivers/hwtracing/coresight/of_coresight.c
+++ b/drivers/hwtracing/coresight/of_coresight.c
@@ -45,13 +45,13 @@ of_coresight_get_endpoint_device(struct device_node *endpoint)
 			       endpoint, of_dev_node_match);
 }
 
-static inline bool of_coresight_ep_is_input(struct device_node *ep)
+static inline bool of_coresight_legacy_ep_is_input(struct device_node *ep)
 {
 	return of_property_read_bool(ep, "slave-mode");
 }
 
-static void of_coresight_get_ports(const struct device_node *node,
-				   int *nr_inport, int *nr_outport)
+static void of_coresight_get_ports_legacy(const struct device_node *node,
+					  int *nr_inport, int *nr_outport)
 {
 	struct device_node *ep = NULL;
 	int in = 0, out = 0;
@@ -61,7 +61,7 @@ static void of_coresight_get_ports(const struct device_node *node,
 		if (!ep)
 			break;
 
-		if (of_coresight_ep_is_input(ep))
+		if (of_coresight_legacy_ep_is_input(ep))
 			in++;
 		else
 			out++;
@@ -72,6 +72,67 @@ static void of_coresight_get_ports(const struct device_node *node,
 	*nr_outport = out;
 }
 
+static struct device_node *of_coresight_get_port_parent(struct device_node *ep)
+{
+	struct device_node *parent = of_graph_get_port_parent(ep);
+
+	/*
+	 * Skip one-level up to the real device node, if we
+	 * are using the new bindings.
+	 */
+	if (!of_node_cmp(parent->name, "in-ports") ||
+	    !of_node_cmp(parent->name, "out-ports"))
+		parent = of_get_next_parent(parent);
+
+	return parent;
+}
+
+static inline struct device_node *
+of_coresight_get_input_ports_node(const struct device_node *node)
+{
+	return of_get_child_by_name(node, "in-ports");
+}
+
+static inline struct device_node *
+of_coresight_get_output_ports_node(const struct device_node *node)
+{
+	return of_get_child_by_name(node, "out-ports");
+}
+
+static inline int
+of_coresight_count_ports(struct device_node *port_parent)
+{
+	int i = 0;
+	struct device_node *ep = NULL;
+
+	while ((ep = of_graph_get_next_endpoint(port_parent, ep)))
+		i++;
+	return i;
+}
+
+static void of_coresight_get_ports(const struct device_node *node,
+				   int *nr_inport, int *nr_outport)
+{
+	struct device_node *input_ports = NULL, *output_ports = NULL;
+
+	input_ports = of_coresight_get_input_ports_node(node);
+	output_ports = of_coresight_get_output_ports_node(node);
+
+	if (input_ports || output_ports) {
+		if (input_ports) {
+			*nr_inport = of_coresight_count_ports(input_ports);
+			of_node_put(input_ports);
+		}
+		if (output_ports) {
+			*nr_outport = of_coresight_count_ports(output_ports);
+			of_node_put(output_ports);
+		}
+	} else {
+		/* Fall back to legacy DT bindings parsing */
+		of_coresight_get_ports_legacy(node, nr_inport, nr_outport);
+	}
+}
+
 static int of_coresight_alloc_memory(struct device *dev,
 			struct coresight_platform_data *pdata)
 {
@@ -136,7 +197,7 @@ static int of_coresight_parse_endpoint(struct device *dev,
 		rep = of_graph_get_remote_endpoint(ep);
 		if (!rep)
 			break;
-		rparent = of_graph_get_port_parent(rep);
+		rparent = of_coresight_get_port_parent(rep);
 		if (!rparent)
 			break;
 		if (of_graph_parse_endpoint(rep, &rendpoint))
@@ -176,6 +237,8 @@ of_get_coresight_platform_data(struct device *dev,
 	struct coresight_platform_data *pdata;
 	struct coresight_connection *conn;
 	struct device_node *ep = NULL;
+	const struct device_node *parent = NULL;
+	bool legacy_binding = false;
 
 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
 	if (!pdata)
@@ -196,14 +259,29 @@ of_get_coresight_platform_data(struct device *dev,
 	if (ret)
 		return ERR_PTR(ret);
 
+	parent = of_coresight_get_output_ports_node(node);
+	/*
+	 * If the DT uses obsoleted bindings, the ports are listed
+	 * under the device and we need to filter out the input
+	 * ports.
+	 */
+	if (!parent) {
+		legacy_binding = true;
+		parent = node;
+		dev_warn_once(dev, "Uses obsolete Coresight DT bindings\n");
+	}
+
 	conn = pdata->conns;
-	/* Iterate through each port to discover topology */
-	while ((ep = of_graph_get_next_endpoint(node, ep))) {
+
+	/* Iterate through each output port to discover topology */
+	while ((ep = of_graph_get_next_endpoint(parent, ep))) {
 		/*
-		 * No need to deal with input ports, as processing the
-		 * output ports connected to them will process the details.
+		 * Legacy binding mixes input/output ports under the
+		 * same parent. So, skip the input ports if we are dealing
+		 * with legacy binding, as they processed with their
+		 * connected output ports.
 		 */
-		if (of_coresight_ep_is_input(ep))
+		if (legacy_binding && of_coresight_legacy_ep_is_input(ep))
 			continue;
 
 		ret = of_coresight_parse_endpoint(dev, ep, conn);
-- 
2.7.4

[PATCH 09/44] coresight: Use ERR_CAST instead of ERR_PTR

[Mathieu Poirier]

From: zhong jiang <zhongjiang@huawei.com>

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

diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
index 2eda5de304c2..11963647e19a 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
@@ -536,7 +536,7 @@ tmc_init_etr_sg_table(struct device *dev, int node,
 	sg_table = tmc_alloc_sg_table(dev, node, nr_tpages, nr_dpages, pages);
 	if (IS_ERR(sg_table)) {
 		kfree(etr_table);
-		return ERR_PTR(PTR_ERR(sg_table));
+		return ERR_CAST(sg_table);
 	}
 
 	etr_table->sg_table = sg_table;
-- 
2.7.4

[PATCH 10/44] coresight: Fix handling of sinks

[Mathieu Poirier]

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

The coresight components could be operated either in sysfs mode or in perf
mode. For some of the components, the mode of operation doesn't matter as
they simply relay the data to the next component in the trace path. But for
sinks, they need to be able to provide the trace data back to the user.
Thus we need to make sure that "mode" is handled appropriately. e.g,
the sysfs mode could have multiple sources driving the trace data, while
perf mode doesn't allow sharing the sink.

The coresight_enable_sink() however doesn't really allow this check to
trigger as it skips the "enable_sink" callback if the component is
already enabled, irrespective of the mode. This could cause mixing
of data from different modes or even same mode (in perf), if the
sources are different. Also, if we fail to enable the sink while
enabling a path (where sink is the first component enabled),
we could end up in disabling the components in the "entire"
path which were not enabled in this trial, causing disruptions
in the existing trace paths.

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.c | 22 +++++++++++++++-------
 1 file changed, 15 insertions(+), 7 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight.c b/drivers/hwtracing/coresight/coresight.c
index 5e8880ca8078..07382c55b31d 100644
--- a/drivers/hwtracing/coresight/coresight.c
+++ b/drivers/hwtracing/coresight/coresight.c
@@ -132,12 +132,14 @@ static int coresight_enable_sink(struct coresight_device *csdev, u32 mode)
 {
 	int ret;
 
-	if (!csdev->enable) {
-		if (sink_ops(csdev)->enable) {
-			ret = sink_ops(csdev)->enable(csdev, mode);
-			if (ret)
-				return ret;
-		}
+	/*
+	 * We need to make sure the "new" session is compatible with the
+	 * existing "mode" of operation.
+	 */
+	if (sink_ops(csdev)->enable) {
+		ret = sink_ops(csdev)->enable(csdev, mode);
+		if (ret)
+			return ret;
 		csdev->enable = true;
 	}
 
@@ -339,8 +341,14 @@ int coresight_enable_path(struct list_head *path, u32 mode)
 		switch (type) {
 		case CORESIGHT_DEV_TYPE_SINK:
 			ret = coresight_enable_sink(csdev, mode);
+			/*
+			 * Sink is the first component turned on. If we
+			 * failed to enable the sink, there are no components
+			 * that need disabling. Disabling the path here
+			 * would mean we could disrupt an existing session.
+			 */
 			if (ret)
-				goto err;
+				goto out;
 			break;
 		case CORESIGHT_DEV_TYPE_SOURCE:
 			/* sources are enabled from either sysFS or Perf */
-- 
2.7.4

[PATCH 11/44] coresight: etb10: Fix handling of perf mode

[Mathieu Poirier]

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

If the ETB is already enabled in sysfs mode, the ETB reports
success even if a perf mode is requested. Fix this by checking
the requested 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>
---
 drivers/hwtracing/coresight/coresight-etb10.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/hwtracing/coresight/coresight-etb10.c b/drivers/hwtracing/coresight/coresight-etb10.c
index 306119eaf16a..0dad8626bcfb 100644
--- a/drivers/hwtracing/coresight/coresight-etb10.c
+++ b/drivers/hwtracing/coresight/coresight-etb10.c
@@ -147,6 +147,10 @@ static int etb_enable(struct coresight_device *csdev, u32 mode)
 	if (val == CS_MODE_PERF)
 		return -EBUSY;
 
+	/* Don't let perf disturb sysFS sessions */
+	if (val == CS_MODE_SYSFS && mode == CS_MODE_PERF)
+		return -EBUSY;
+
 	/* Nothing to do, the tracer is already enabled. */
 	if (val == CS_MODE_SYSFS)
 		goto out;
-- 
2.7.4

[PATCH 12/44] coresight: perf: Fix per cpu path management

[Mathieu Poirier]

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

We create a coresight trace path for each online CPU when
we start the event. We rely on the number of online CPUs
and then go on to allocate an array matching the "number of
online CPUs" for holding the path and then uses normal
CPU id as the index to the array. This is problematic as
we could have some offline CPUs causing us to access beyond
the actual array size (e.g, on a dual SMP system, if CPU0 is
offline, CPU1 could be really accessing beyond the array).
The solution is to switch to per-cpu array for holding the path.

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-etm-perf.c | 55 +++++++++++++++++-------
 1 file changed, 40 insertions(+), 15 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c
index 677695635211..6338dd180031 100644
--- a/drivers/hwtracing/coresight/coresight-etm-perf.c
+++ b/drivers/hwtracing/coresight/coresight-etm-perf.c
@@ -12,6 +12,7 @@
 #include <linux/mm.h>
 #include <linux/init.h>
 #include <linux/perf_event.h>
+#include <linux/percpu-defs.h>
 #include <linux/slab.h>
 #include <linux/types.h>
 #include <linux/workqueue.h>
@@ -33,7 +34,7 @@ struct etm_event_data {
 	struct work_struct work;
 	cpumask_t mask;
 	void *snk_config;
-	struct list_head **path;
+	struct list_head * __percpu *path;
 };
 
 static DEFINE_PER_CPU(struct perf_output_handle, ctx_handle);
@@ -61,6 +62,18 @@ static const struct attribute_group *etm_pmu_attr_groups[] = {
 	NULL,
 };
 
+static inline struct list_head **
+etm_event_cpu_path_ptr(struct etm_event_data *data, int cpu)
+{
+	return per_cpu_ptr(data->path, cpu);
+}
+
+static inline struct list_head *
+etm_event_cpu_path(struct etm_event_data *data, int cpu)
+{
+	return *etm_event_cpu_path_ptr(data, cpu);
+}
+
 static void etm_event_read(struct perf_event *event) {}
 
 static int etm_addr_filters_alloc(struct perf_event *event)
@@ -120,23 +133,26 @@ static void free_event_data(struct work_struct *work)
 	 */
 	if (event_data->snk_config) {
 		cpu = cpumask_first(mask);
-		sink = coresight_get_sink(event_data->path[cpu]);
+		sink = coresight_get_sink(etm_event_cpu_path(event_data, cpu));
 		if (sink_ops(sink)->free_buffer)
 			sink_ops(sink)->free_buffer(event_data->snk_config);
 	}
 
 	for_each_cpu(cpu, mask) {
-		if (!(IS_ERR_OR_NULL(event_data->path[cpu])))
-			coresight_release_path(event_data->path[cpu]);
+		struct list_head **ppath;
+
+		ppath = etm_event_cpu_path_ptr(event_data, cpu);
+		if (!(IS_ERR_OR_NULL(*ppath)))
+			coresight_release_path(*ppath);
+		*ppath = NULL;
 	}
 
-	kfree(event_data->path);
+	free_percpu(event_data->path);
 	kfree(event_data);
 }
 
 static void *alloc_event_data(int cpu)
 {
-	int size;
 	cpumask_t *mask;
 	struct etm_event_data *event_data;
 
@@ -147,7 +163,6 @@ static void *alloc_event_data(int cpu)
 
 	/* Make sure nothing disappears under us */
 	get_online_cpus();
-	size = num_online_cpus();
 
 	mask = &event_data->mask;
 	if (cpu != -1)
@@ -164,8 +179,8 @@ static void *alloc_event_data(int cpu)
 	 * unused memory when dealing with single CPU trace scenarios is small
 	 * compared to the cost of searching through an optimized array.
 	 */
-	event_data->path = kcalloc(size,
-				   sizeof(struct list_head *), GFP_KERNEL);
+	event_data->path = alloc_percpu(struct list_head *);
+
 	if (!event_data->path) {
 		kfree(event_data);
 		return NULL;
@@ -213,6 +228,7 @@ static void *etm_setup_aux(int event_cpu, void **pages,
 
 	/* Setup the path for each CPU in a trace session */
 	for_each_cpu(cpu, mask) {
+		struct list_head *path;
 		struct coresight_device *csdev;
 
 		csdev = per_cpu(csdev_src, cpu);
@@ -224,9 +240,11 @@ 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, sink);
-		if (IS_ERR(event_data->path[cpu]))
+		path = coresight_build_path(csdev, sink);
+		if (IS_ERR(path))
 			goto err;
+
+		*etm_event_cpu_path_ptr(event_data, cpu) = path;
 	}
 
 	if (!sink_ops(sink)->alloc_buffer)
@@ -255,6 +273,7 @@ static void etm_event_start(struct perf_event *event, int flags)
 	struct etm_event_data *event_data;
 	struct perf_output_handle *handle = this_cpu_ptr(&ctx_handle);
 	struct coresight_device *sink, *csdev = per_cpu(csdev_src, cpu);
+	struct list_head *path;
 
 	if (!csdev)
 		goto fail;
@@ -267,8 +286,9 @@ static void etm_event_start(struct perf_event *event, int flags)
 	if (!event_data)
 		goto fail;
 
+	path = etm_event_cpu_path(event_data, cpu);
 	/* We need a sink, no need to continue without one */
-	sink = coresight_get_sink(event_data->path[cpu]);
+	sink = coresight_get_sink(path);
 	if (WARN_ON_ONCE(!sink || !sink_ops(sink)->set_buffer))
 		goto fail_end_stop;
 
@@ -278,7 +298,7 @@ static void etm_event_start(struct perf_event *event, int flags)
 		goto fail_end_stop;
 
 	/* Nothing will happen without a path */
-	if (coresight_enable_path(event_data->path[cpu], CS_MODE_PERF))
+	if (coresight_enable_path(path, CS_MODE_PERF))
 		goto fail_end_stop;
 
 	/* Tell the perf core the event is alive */
@@ -306,6 +326,7 @@ static void etm_event_stop(struct perf_event *event, int mode)
 	struct coresight_device *sink, *csdev = per_cpu(csdev_src, cpu);
 	struct perf_output_handle *handle = this_cpu_ptr(&ctx_handle);
 	struct etm_event_data *event_data = perf_get_aux(handle);
+	struct list_head *path;
 
 	if (event->hw.state == PERF_HES_STOPPED)
 		return;
@@ -313,7 +334,11 @@ static void etm_event_stop(struct perf_event *event, int mode)
 	if (!csdev)
 		return;
 
-	sink = coresight_get_sink(event_data->path[cpu]);
+	path = etm_event_cpu_path(event_data, cpu);
+	if (!path)
+		return;
+
+	sink = coresight_get_sink(path);
 	if (!sink)
 		return;
 
@@ -344,7 +369,7 @@ static void etm_event_stop(struct perf_event *event, int mode)
 	}
 
 	/* Disabling the path make its elements available to other sessions */
-	coresight_disable_path(event_data->path[cpu]);
+	coresight_disable_path(path);
 }
 
 static int etm_event_add(struct perf_event *event, int mode)
-- 
2.7.4

[PATCH 13/44] coresight: perf: Avoid unncessary CPU hotplug read lock

[Mathieu Poirier]

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

We hold the read lock on CPU hotplug to simply copy the
online mask, which is not really needed. And this can
cause a lockdep warning, like :

[   54.632093] ======================================================
[   54.638207] WARNING: possible circular locking dependency detected
[   54.644322] 4.18.0-rc3-00042-g2d39e6356bb7-dirty #309 Not tainted
[   54.650350] ------------------------------------------------------
[   54.656464] perf/2862 is trying to acquire lock:
[   54.661031] 000000007e21d170 (&event->mmap_mutex){+.+.}, at: perf_event_set_output+0x98/0x138
[   54.669486]
[   54.669486] but task is already holding lock:
[   54.675256] 000000001080eb1b (&cpuctx_mutex){+.+.}, at: perf_event_ctx_lock_nested+0xf8/0x1f0
[   54.683704]
[   54.683704] which lock already depends on the new lock.
[   54.683704]
[   54.691797]
[   54.691797] the existing dependency chain (in reverse order) is:
[   54.699201]
[   54.699201] -> #3 (&cpuctx_mutex){+.+.}:
[   54.704556]        __mutex_lock+0x70/0x808
[   54.708608]        mutex_lock_nested+0x1c/0x28
[   54.713005]        perf_event_init_cpu+0x8c/0xd8
[   54.717574]        perf_event_init+0x194/0x1d4
[   54.721971]        start_kernel+0x2b8/0x42c
[   54.726107]
[   54.726107] -> #2 (pmus_lock){+.+.}:
[   54.731114]        __mutex_lock+0x70/0x808
[   54.735165]        mutex_lock_nested+0x1c/0x28
[   54.739560]        perf_event_init_cpu+0x30/0xd8
[   54.744129]        cpuhp_invoke_callback+0x84/0x248
[   54.748954]        _cpu_up+0xe8/0x1c8
[   54.752576]        do_cpu_up+0xa8/0xc8
[   54.756283]        cpu_up+0x10/0x18
[   54.759731]        smp_init+0xa0/0x114
[   54.763438]        kernel_init_freeable+0x120/0x288
[   54.768264]        kernel_init+0x10/0x108
[   54.772230]        ret_from_fork+0x10/0x18
[   54.776279]
[   54.776279] -> #1 (cpu_hotplug_lock.rw_sem){++++}:
[   54.782492]        cpus_read_lock+0x34/0xb0
[   54.786631]        etm_setup_aux+0x5c/0x308
[   54.790769]        rb_alloc_aux+0x1ec/0x300
[   54.794906]        perf_mmap+0x284/0x610
[   54.798787]        mmap_region+0x388/0x570
[   54.802838]        do_mmap+0x344/0x4f8
[   54.806544]        vm_mmap_pgoff+0xe4/0x110
[   54.810682]        ksys_mmap_pgoff+0xa8/0x240
[   54.814992]        sys_mmap+0x18/0x28
[   54.818613]        el0_svc_naked+0x30/0x34
[   54.822661]
[   54.822661] -> #0 (&event->mmap_mutex){+.+.}:
[   54.828445]        lock_acquire+0x48/0x68
[   54.832409]        __mutex_lock+0x70/0x808
[   54.836459]        mutex_lock_nested+0x1c/0x28
[   54.840855]        perf_event_set_output+0x98/0x138
[   54.845680]        _perf_ioctl+0x2a0/0x6a0
[   54.849731]        perf_ioctl+0x3c/0x68
[   54.853526]        do_vfs_ioctl+0xb8/0xa20
[   54.857577]        ksys_ioctl+0x80/0xb8
[   54.861370]        sys_ioctl+0xc/0x18
[   54.864990]        el0_svc_naked+0x30/0x34
[   54.869039]
[   54.869039] other info that might help us debug this:
[   54.869039]
[   54.876960] Chain exists of:
[   54.876960]   &event->mmap_mutex --> pmus_lock --> &cpuctx_mutex
[   54.876960]
[   54.887217]  Possible unsafe locking scenario:
[   54.887217]
[   54.893073]        CPU0                    CPU1
[   54.897552]        ----                    ----
[   54.902030]   lock(&cpuctx_mutex);
[   54.905396]                                lock(pmus_lock);
[   54.910911]                                lock(&cpuctx_mutex);
[   54.916770]   lock(&event->mmap_mutex);
[   54.920566]
[   54.920566]  *** DEADLOCK ***
[   54.920566]
[   54.926424] 1 lock held by perf/2862:
[   54.930042]  #0: 000000001080eb1b (&cpuctx_mutex){+.+.}, at: perf_event_ctx_lock_nested+0xf8/0x1f0

Since we have per-cpu array for the paths, we simply don't care about
the number of online CPUs. This patch gets rid of the
{get/put}_online_cpus().

Reported-by: 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-etm-perf.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c
index 6338dd180031..6beb662d230c 100644
--- a/drivers/hwtracing/coresight/coresight-etm-perf.c
+++ b/drivers/hwtracing/coresight/coresight-etm-perf.c
@@ -161,15 +161,12 @@ static void *alloc_event_data(int cpu)
 	if (!event_data)
 		return NULL;
 
-	/* Make sure nothing disappears under us */
-	get_online_cpus();
 
 	mask = &event_data->mask;
 	if (cpu != -1)
 		cpumask_set_cpu(cpu, mask);
 	else
 		cpumask_copy(mask, cpu_online_mask);
-	put_online_cpus();
 
 	/*
 	 * Each CPU has a single path between source and destination.  As such
-- 
2.7.4

[PATCH 14/44] coresight: perf: Allow tracing on hotplugged CPUs

[Mathieu Poirier]

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

At the moment, if there is no CPU specified for a given
event, we use cpu_online_mask and try to build path for
each of the CPUs in the mask. This could prevent any CPU
that is turned online later to be used for the tracing.

This patch changes to use the cpu_present_mask and tries
to build path for as much CPUs as possible ignoring the
failures in building path for some of the CPUs. If ever
we try to trace on those CPUs, we fail the operation.

Based on a patch from Mathieu Poirier.

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-etm-perf.c | 44 ++++++++++++++++--------
 1 file changed, 29 insertions(+), 15 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c
index 6beb662d230c..afe7e7fc1a93 100644
--- a/drivers/hwtracing/coresight/coresight-etm-perf.c
+++ b/drivers/hwtracing/coresight/coresight-etm-perf.c
@@ -127,11 +127,9 @@ static void free_event_data(struct work_struct *work)
 
 	event_data = container_of(work, struct etm_event_data, work);
 	mask = &event_data->mask;
-	/*
-	 * First deal with the sink configuration.  See comment in
-	 * etm_setup_aux() about why we take the first available path.
-	 */
-	if (event_data->snk_config) {
+
+	/* Free the sink buffers, if there are any */
+	if (event_data->snk_config && !WARN_ON(cpumask_empty(mask))) {
 		cpu = cpumask_first(mask);
 		sink = coresight_get_sink(etm_event_cpu_path(event_data, cpu));
 		if (sink_ops(sink)->free_buffer)
@@ -166,7 +164,7 @@ static void *alloc_event_data(int cpu)
 	if (cpu != -1)
 		cpumask_set_cpu(cpu, mask);
 	else
-		cpumask_copy(mask, cpu_online_mask);
+		cpumask_copy(mask, cpu_present_mask);
 
 	/*
 	 * Each CPU has a single path between source and destination.  As such
@@ -218,19 +216,32 @@ static void *etm_setup_aux(int event_cpu, void **pages,
 	 * on the cmd line.  As such the "enable_sink" flag in sysFS is reset.
 	 */
 	sink = coresight_get_enabled_sink(true);
-	if (!sink)
+	if (!sink || !sink_ops(sink)->alloc_buffer)
 		goto err;
 
 	mask = &event_data->mask;
 
-	/* Setup the path for each CPU in a trace session */
+	/*
+	 * Setup the path for each CPU in a trace session. We try to build
+	 * trace path for each CPU in the mask. If we don't find an ETM
+	 * for the CPU or fail to build a path, we clear the CPU from the
+	 * mask and continue with the rest. If ever we try to trace on those
+	 * CPUs, we can handle it and fail the session.
+	 */
 	for_each_cpu(cpu, mask) {
 		struct list_head *path;
 		struct coresight_device *csdev;
 
 		csdev = per_cpu(csdev_src, cpu);
-		if (!csdev)
-			goto err;
+		/*
+		 * If there is no ETM associated with this CPU clear it from
+		 * the mask and continue with the rest. If ever we try to trace
+		 * on this CPU, we handle it accordingly.
+		 */
+		if (!csdev) {
+			cpumask_clear_cpu(cpu, mask);
+			continue;
+		}
 
 		/*
 		 * Building a path doesn't enable it, it simply builds a
@@ -238,17 +249,20 @@ static void *etm_setup_aux(int event_cpu, void **pages,
 		 * referenced later when the path is actually needed.
 		 */
 		path = coresight_build_path(csdev, sink);
-		if (IS_ERR(path))
-			goto err;
+		if (IS_ERR(path)) {
+			cpumask_clear_cpu(cpu, mask);
+			continue;
+		}
 
 		*etm_event_cpu_path_ptr(event_data, cpu) = path;
 	}
 
-	if (!sink_ops(sink)->alloc_buffer)
+	/* If we don't have any CPUs ready for tracing, abort */
+	cpu = cpumask_first(mask);
+	if (cpu >= nr_cpu_ids)
 		goto err;
 
-	cpu = cpumask_first(mask);
-	/* Get the AUX specific data from the sink buffer */
+	/* Allocate the sink buffer for this session */
 	event_data->snk_config =
 			sink_ops(sink)->alloc_buffer(sink, cpu, pages,
 						     nr_pages, overwrite);
-- 
2.7.4

[PATCH 15/44] coresight: perf: Disable trace path upon source error

[Mathieu Poirier]

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

We enable the trace path, before activating the source.
If we fail to enable the source, we must disable the path
to make sure it is available for another 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>
---
 drivers/hwtracing/coresight/coresight-etm-perf.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c
index afe7e7fc1a93..6db76ce6ba5f 100644
--- a/drivers/hwtracing/coresight/coresight-etm-perf.c
+++ b/drivers/hwtracing/coresight/coresight-etm-perf.c
@@ -317,11 +317,13 @@ static void etm_event_start(struct perf_event *event, int flags)
 
 	/* Finally enable the tracer */
 	if (source_ops(csdev)->enable(csdev, event, CS_MODE_PERF))
-		goto fail_end_stop;
+		goto fail_disable_path;
 
 out:
 	return;
 
+fail_disable_path:
+	coresight_disable_path(path);
 fail_end_stop:
 	perf_aux_output_flag(handle, PERF_AUX_FLAG_TRUNCATED);
 	perf_aux_output_end(handle, 0);
-- 
2.7.4

[PATCH 16/44] coresight: tmc-etr: Handle driver mode specific ETR buffers

[Mathieu Poirier]

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

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>
---
 drivers/hwtracing/coresight/coresight-tmc-etr.c | 58 ++++++++++++++++---------
 drivers/hwtracing/coresight/coresight-tmc.h     |  2 +
 2 files changed, 40 insertions(+), 20 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
index 11963647e19a..2d6f428176ff 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
@@ -895,10 +895,15 @@ static void tmc_sync_etr_buf(struct tmc_drvdata *drvdata)
 		tmc_etr_buf_insert_barrier_packet(etr_buf, etr_buf->offset);
 }
 
-static void tmc_etr_enable_hw(struct tmc_drvdata *drvdata)
+static void tmc_etr_enable_hw(struct tmc_drvdata *drvdata,
+			      struct etr_buf *etr_buf)
 {
 	u32 axictl, sts;
-	struct etr_buf *etr_buf = drvdata->etr_buf;
+
+	/* Callers should provide an appropriate buffer for use */
+	if (WARN_ON(!etr_buf || drvdata->etr_buf))
+		return;
+	drvdata->etr_buf = etr_buf;
 
 	/*
 	 * If this ETR is connected to a CATU, enable it before we turn
@@ -960,13 +965,16 @@ static void tmc_etr_enable_hw(struct tmc_drvdata *drvdata)
  * also updating the @bufpp on where to find it. Since the trace data
  * starts at anywhere in the buffer, depending on the RRP, we adjust the
  * @len returned to handle buffer wrapping around.
+ *
+ * We are protected here by drvdata->reading != 0, which ensures the
+ * sysfs_buf stays alive.
  */
 ssize_t tmc_etr_get_sysfs_trace(struct tmc_drvdata *drvdata,
 				loff_t pos, size_t len, char **bufpp)
 {
 	s64 offset;
 	ssize_t actual = len;
-	struct etr_buf *etr_buf = drvdata->etr_buf;
+	struct etr_buf *etr_buf = drvdata->sysfs_buf;
 
 	if (pos + actual > etr_buf->len)
 		actual = etr_buf->len - pos;
@@ -996,7 +1004,14 @@ tmc_etr_free_sysfs_buf(struct etr_buf *buf)
 
 static void tmc_etr_sync_sysfs_buf(struct tmc_drvdata *drvdata)
 {
-	tmc_sync_etr_buf(drvdata);
+	struct etr_buf *etr_buf = drvdata->etr_buf;
+
+	if (WARN_ON(drvdata->sysfs_buf != etr_buf)) {
+		tmc_etr_free_sysfs_buf(drvdata->sysfs_buf);
+		drvdata->sysfs_buf = NULL;
+	} else {
+		tmc_sync_etr_buf(drvdata);
+	}
 }
 
 static void tmc_etr_disable_hw(struct tmc_drvdata *drvdata)
@@ -1017,6 +1032,8 @@ static void tmc_etr_disable_hw(struct tmc_drvdata *drvdata)
 
 	/* Disable CATU device if this ETR is connected to one */
 	tmc_etr_disable_catu(drvdata);
+	/* Reset the ETR buf used by hardware */
+	drvdata->etr_buf = NULL;
 }
 
 static int tmc_enable_etr_sink_sysfs(struct coresight_device *csdev)
@@ -1024,7 +1041,7 @@ static int tmc_enable_etr_sink_sysfs(struct coresight_device *csdev)
 	int ret = 0;
 	unsigned long flags;
 	struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
-	struct etr_buf *new_buf = NULL, *free_buf = NULL;
+	struct etr_buf *sysfs_buf = NULL, *new_buf = NULL, *free_buf = NULL;
 
 	/*
 	 * If we are enabling the ETR from disabled state, we need to make
@@ -1035,7 +1052,8 @@ static int tmc_enable_etr_sink_sysfs(struct coresight_device *csdev)
 	 * with the lock released.
 	 */
 	spin_lock_irqsave(&drvdata->spinlock, flags);
-	if (!drvdata->etr_buf || (drvdata->etr_buf->size != drvdata->size)) {
+	sysfs_buf = READ_ONCE(drvdata->sysfs_buf);
+	if (!sysfs_buf || (sysfs_buf->size != drvdata->size)) {
 		spin_unlock_irqrestore(&drvdata->spinlock, flags);
 
 		/* Allocate memory with the locks released */
@@ -1064,14 +1082,14 @@ static int tmc_enable_etr_sink_sysfs(struct coresight_device *csdev)
 	 * If we don't have a buffer or it doesn't match the requested size,
 	 * use the buffer allocated above. Otherwise reuse the existing buffer.
 	 */
-	if (!drvdata->etr_buf ||
-	    (new_buf && drvdata->etr_buf->size != new_buf->size)) {
-		free_buf = drvdata->etr_buf;
-		drvdata->etr_buf = new_buf;
+	sysfs_buf = READ_ONCE(drvdata->sysfs_buf);
+	if (!sysfs_buf || (new_buf && sysfs_buf->size != new_buf->size)) {
+		free_buf = sysfs_buf;
+		drvdata->sysfs_buf = new_buf;
 	}
 
 	drvdata->mode = CS_MODE_SYSFS;
-	tmc_etr_enable_hw(drvdata);
+	tmc_etr_enable_hw(drvdata, drvdata->sysfs_buf);
 out:
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
 
@@ -1156,13 +1174,13 @@ int tmc_read_prepare_etr(struct tmc_drvdata *drvdata)
 		goto out;
 	}
 
-	/* If drvdata::etr_buf is NULL the trace data has been read already */
-	if (drvdata->etr_buf == NULL) {
+	/* If sysfs_buf is NULL the trace data has been read already */
+	if (!drvdata->sysfs_buf) {
 		ret = -EINVAL;
 		goto out;
 	}
 
-	/* Disable the TMC if need be */
+	/* Disable the TMC if we are trying to read from a running session */
 	if (drvdata->mode == CS_MODE_SYSFS)
 		tmc_etr_disable_hw(drvdata);
 
@@ -1176,7 +1194,7 @@ int tmc_read_prepare_etr(struct tmc_drvdata *drvdata)
 int tmc_read_unprepare_etr(struct tmc_drvdata *drvdata)
 {
 	unsigned long flags;
-	struct etr_buf *etr_buf = NULL;
+	struct etr_buf *sysfs_buf = NULL;
 
 	/* config types are set a boot time and never change */
 	if (WARN_ON_ONCE(drvdata->config_type != TMC_CONFIG_TYPE_ETR))
@@ -1191,22 +1209,22 @@ int tmc_read_unprepare_etr(struct tmc_drvdata *drvdata)
 		 * buffer. Since the tracer is still enabled drvdata::buf can't
 		 * be NULL.
 		 */
-		tmc_etr_enable_hw(drvdata);
+		tmc_etr_enable_hw(drvdata, drvdata->sysfs_buf);
 	} else {
 		/*
 		 * The ETR is not tracing and the buffer was just read.
 		 * As such prepare to free the trace buffer.
 		 */
-		etr_buf =  drvdata->etr_buf;
-		drvdata->etr_buf = NULL;
+		sysfs_buf = drvdata->sysfs_buf;
+		drvdata->sysfs_buf = NULL;
 	}
 
 	drvdata->reading = false;
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
 
 	/* Free allocated memory out side of the spinlock */
-	if (etr_buf)
-		tmc_free_etr_buf(etr_buf);
+	if (sysfs_buf)
+		tmc_etr_free_sysfs_buf(sysfs_buf);
 
 	return 0;
 }
diff --git a/drivers/hwtracing/coresight/coresight-tmc.h b/drivers/hwtracing/coresight/coresight-tmc.h
index 7027bd60c4cc..872f63e3651b 100644
--- a/drivers/hwtracing/coresight/coresight-tmc.h
+++ b/drivers/hwtracing/coresight/coresight-tmc.h
@@ -170,6 +170,7 @@ struct etr_buf {
  * @trigger_cntr: amount of words to store after a trigger.
  * @etr_caps:	Bitmask of capabilities of the TMC ETR, inferred from the
  *		device configuration register (DEVID)
+ * @sysfs_data:	SYSFS buffer for ETR.
  */
 struct tmc_drvdata {
 	void __iomem		*base;
@@ -189,6 +190,7 @@ struct tmc_drvdata {
 	enum tmc_mem_intf_width	memwidth;
 	u32			trigger_cntr;
 	u32			etr_caps;
+	struct etr_buf		*sysfs_buf;
 };
 
 struct etr_buf_operations {
-- 
2.7.4

[PATCH 17/44] coresight: tmc-etr: Relax collection of trace from sysfs mode

[Mathieu Poirier]

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

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>
---
 drivers/hwtracing/coresight/coresight-tmc-etr.c | 14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
index 2d6f428176ff..bafd73e71c4c 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
@@ -1168,19 +1168,17 @@ int tmc_read_prepare_etr(struct tmc_drvdata *drvdata)
 		goto out;
 	}
 
-	/* Don't interfere if operated from Perf */
-	if (drvdata->mode == CS_MODE_PERF) {
-		ret = -EINVAL;
-		goto out;
-	}
-
-	/* If sysfs_buf is NULL the trace data has been read already */
+	/*
+	 * We can safely allow reads even if the ETR is operating in PERF mode,
+	 * since the sysfs session is captured in mode specific data.
+	 * If drvdata::sysfs_data is NULL the trace data has been read already.
+	 */
 	if (!drvdata->sysfs_buf) {
 		ret = -EINVAL;
 		goto out;
 	}
 
-	/* Disable the TMC if we are trying to read from a running session */
+	/* Disable the TMC if we are trying to read from a running session. */
 	if (drvdata->mode == CS_MODE_SYSFS)
 		tmc_etr_disable_hw(drvdata);
 
-- 
2.7.4

[PATCH 18/44] coresight: Convert driver messages to dev_dbg

[Mathieu Poirier]

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

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>
---
 drivers/hwtracing/coresight/coresight-dynamic-replicator.c | 4 ++--
 drivers/hwtracing/coresight/coresight-etb10.c              | 6 +++---
 drivers/hwtracing/coresight/coresight-etm3x.c              | 4 ++--
 drivers/hwtracing/coresight/coresight-etm4x.c              | 4 ++--
 drivers/hwtracing/coresight/coresight-funnel.c             | 4 ++--
 drivers/hwtracing/coresight/coresight-replicator.c         | 4 ++--
 drivers/hwtracing/coresight/coresight-stm.c                | 4 ++--
 drivers/hwtracing/coresight/coresight-tmc-etf.c            | 8 ++++----
 drivers/hwtracing/coresight/coresight-tmc-etr.c            | 4 ++--
 drivers/hwtracing/coresight/coresight-tmc.c                | 4 ++--
 drivers/hwtracing/coresight/coresight-tpiu.c               | 4 ++--
 11 files changed, 25 insertions(+), 25 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-dynamic-replicator.c b/drivers/hwtracing/coresight/coresight-dynamic-replicator.c
index f6d0571ab9dd..ebb80438f6a5 100644
--- a/drivers/hwtracing/coresight/coresight-dynamic-replicator.c
+++ b/drivers/hwtracing/coresight/coresight-dynamic-replicator.c
@@ -56,7 +56,7 @@ static int replicator_enable(struct coresight_device *csdev, int inport,
 
 	CS_LOCK(drvdata->base);
 
-	dev_info(drvdata->dev, "REPLICATOR enabled\n");
+	dev_dbg(drvdata->dev, "REPLICATOR enabled\n");
 	return 0;
 }
 
@@ -75,7 +75,7 @@ static void replicator_disable(struct coresight_device *csdev, int inport,
 
 	CS_LOCK(drvdata->base);
 
-	dev_info(drvdata->dev, "REPLICATOR disabled\n");
+	dev_dbg(drvdata->dev, "REPLICATOR disabled\n");
 }
 
 static const struct coresight_ops_link replicator_link_ops = {
diff --git a/drivers/hwtracing/coresight/coresight-etb10.c b/drivers/hwtracing/coresight/coresight-etb10.c
index 0dad8626bcfb..3d4b6df32a06 100644
--- a/drivers/hwtracing/coresight/coresight-etb10.c
+++ b/drivers/hwtracing/coresight/coresight-etb10.c
@@ -160,7 +160,7 @@ static int etb_enable(struct coresight_device *csdev, u32 mode)
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
 
 out:
-	dev_info(drvdata->dev, "ETB enabled\n");
+	dev_dbg(drvdata->dev, "ETB enabled\n");
 	return 0;
 }
 
@@ -266,7 +266,7 @@ static void etb_disable(struct coresight_device *csdev)
 
 	local_set(&drvdata->mode, CS_MODE_DISABLED);
 
-	dev_info(drvdata->dev, "ETB disabled\n");
+	dev_dbg(drvdata->dev, "ETB disabled\n");
 }
 
 static void *etb_alloc_buffer(struct coresight_device *csdev, int cpu,
@@ -509,7 +509,7 @@ static void etb_dump(struct etb_drvdata *drvdata)
 	}
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
 
-	dev_info(drvdata->dev, "ETB dumped\n");
+	dev_dbg(drvdata->dev, "ETB dumped\n");
 }
 
 static int etb_open(struct inode *inode, struct file *file)
diff --git a/drivers/hwtracing/coresight/coresight-etm3x.c b/drivers/hwtracing/coresight/coresight-etm3x.c
index 7c74263c333d..9ce8fba20b0f 100644
--- a/drivers/hwtracing/coresight/coresight-etm3x.c
+++ b/drivers/hwtracing/coresight/coresight-etm3x.c
@@ -501,7 +501,7 @@ static int etm_enable_sysfs(struct coresight_device *csdev)
 	drvdata->sticky_enable = true;
 	spin_unlock(&drvdata->spinlock);
 
-	dev_info(drvdata->dev, "ETM tracing enabled\n");
+	dev_dbg(drvdata->dev, "ETM tracing enabled\n");
 	return 0;
 
 err:
@@ -604,7 +604,7 @@ static void etm_disable_sysfs(struct coresight_device *csdev)
 	spin_unlock(&drvdata->spinlock);
 	cpus_read_unlock();
 
-	dev_info(drvdata->dev, "ETM tracing disabled\n");
+	dev_dbg(drvdata->dev, "ETM tracing disabled\n");
 }
 
 static void etm_disable(struct coresight_device *csdev,
diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c
index 1d94ebec027b..c1dcc7c289a5 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x.c
@@ -267,7 +267,7 @@ static int etm4_enable_sysfs(struct coresight_device *csdev)
 	drvdata->sticky_enable = true;
 	spin_unlock(&drvdata->spinlock);
 
-	dev_info(drvdata->dev, "ETM tracing enabled\n");
+	dev_dbg(drvdata->dev, "ETM tracing enabled\n");
 	return 0;
 
 err:
@@ -380,7 +380,7 @@ static void etm4_disable_sysfs(struct coresight_device *csdev)
 	spin_unlock(&drvdata->spinlock);
 	cpus_read_unlock();
 
-	dev_info(drvdata->dev, "ETM tracing disabled\n");
+	dev_dbg(drvdata->dev, "ETM tracing disabled\n");
 }
 
 static void etm4_disable(struct coresight_device *csdev,
diff --git a/drivers/hwtracing/coresight/coresight-funnel.c b/drivers/hwtracing/coresight/coresight-funnel.c
index 448145a36675..ee7a30bf9480 100644
--- a/drivers/hwtracing/coresight/coresight-funnel.c
+++ b/drivers/hwtracing/coresight/coresight-funnel.c
@@ -65,7 +65,7 @@ static int funnel_enable(struct coresight_device *csdev, int inport,
 
 	funnel_enable_hw(drvdata, inport);
 
-	dev_info(drvdata->dev, "FUNNEL inport %d enabled\n", inport);
+	dev_dbg(drvdata->dev, "FUNNEL inport %d enabled\n", inport);
 	return 0;
 }
 
@@ -89,7 +89,7 @@ static void funnel_disable(struct coresight_device *csdev, int inport,
 
 	funnel_disable_hw(drvdata, inport);
 
-	dev_info(drvdata->dev, "FUNNEL inport %d disabled\n", inport);
+	dev_dbg(drvdata->dev, "FUNNEL inport %d disabled\n", inport);
 }
 
 static const struct coresight_ops_link funnel_link_ops = {
diff --git a/drivers/hwtracing/coresight/coresight-replicator.c b/drivers/hwtracing/coresight/coresight-replicator.c
index 8d2eaaab6c2f..feac98315471 100644
--- a/drivers/hwtracing/coresight/coresight-replicator.c
+++ b/drivers/hwtracing/coresight/coresight-replicator.c
@@ -35,7 +35,7 @@ static int replicator_enable(struct coresight_device *csdev, int inport,
 {
 	struct replicator_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
 
-	dev_info(drvdata->dev, "REPLICATOR enabled\n");
+	dev_dbg(drvdata->dev, "REPLICATOR enabled\n");
 	return 0;
 }
 
@@ -44,7 +44,7 @@ static void replicator_disable(struct coresight_device *csdev, int inport,
 {
 	struct replicator_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
 
-	dev_info(drvdata->dev, "REPLICATOR disabled\n");
+	dev_dbg(drvdata->dev, "REPLICATOR disabled\n");
 }
 
 static const struct coresight_ops_link replicator_link_ops = {
diff --git a/drivers/hwtracing/coresight/coresight-stm.c b/drivers/hwtracing/coresight/coresight-stm.c
index c46c70aec1d5..35d6f9709274 100644
--- a/drivers/hwtracing/coresight/coresight-stm.c
+++ b/drivers/hwtracing/coresight/coresight-stm.c
@@ -211,7 +211,7 @@ static int stm_enable(struct coresight_device *csdev,
 	stm_enable_hw(drvdata);
 	spin_unlock(&drvdata->spinlock);
 
-	dev_info(drvdata->dev, "STM tracing enabled\n");
+	dev_dbg(drvdata->dev, "STM tracing enabled\n");
 	return 0;
 }
 
@@ -274,7 +274,7 @@ static void stm_disable(struct coresight_device *csdev,
 		pm_runtime_put(drvdata->dev);
 
 		local_set(&drvdata->mode, CS_MODE_DISABLED);
-		dev_info(drvdata->dev, "STM tracing disabled\n");
+		dev_dbg(drvdata->dev, "STM tracing disabled\n");
 	}
 }
 
diff --git a/drivers/hwtracing/coresight/coresight-tmc-etf.c b/drivers/hwtracing/coresight/coresight-tmc-etf.c
index 0549249f4b39..434003a43346 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etf.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etf.c
@@ -233,7 +233,7 @@ static int tmc_enable_etf_sink(struct coresight_device *csdev, u32 mode)
 	if (ret)
 		return ret;
 
-	dev_info(drvdata->dev, "TMC-ETB/ETF enabled\n");
+	dev_dbg(drvdata->dev, "TMC-ETB/ETF enabled\n");
 	return 0;
 }
 
@@ -256,7 +256,7 @@ static void tmc_disable_etf_sink(struct coresight_device *csdev)
 
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
 
-	dev_info(drvdata->dev, "TMC-ETB/ETF disabled\n");
+	dev_dbg(drvdata->dev, "TMC-ETB/ETF disabled\n");
 }
 
 static int tmc_enable_etf_link(struct coresight_device *csdev,
@@ -275,7 +275,7 @@ static int tmc_enable_etf_link(struct coresight_device *csdev,
 	drvdata->mode = CS_MODE_SYSFS;
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
 
-	dev_info(drvdata->dev, "TMC-ETF enabled\n");
+	dev_dbg(drvdata->dev, "TMC-ETF enabled\n");
 	return 0;
 }
 
@@ -295,7 +295,7 @@ static void tmc_disable_etf_link(struct coresight_device *csdev,
 	drvdata->mode = CS_MODE_DISABLED;
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
 
-	dev_info(drvdata->dev, "TMC-ETF disabled\n");
+	dev_dbg(drvdata->dev, "TMC-ETF disabled\n");
 }
 
 static void *tmc_alloc_etf_buffer(struct coresight_device *csdev, int cpu,
diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
index bafd73e71c4c..5e9bb2f0e9c0 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
@@ -1098,7 +1098,7 @@ static int tmc_enable_etr_sink_sysfs(struct coresight_device *csdev)
 		tmc_etr_free_sysfs_buf(free_buf);
 
 	if (!ret)
-		dev_info(drvdata->dev, "TMC-ETR enabled\n");
+		dev_dbg(drvdata->dev, "TMC-ETR enabled\n");
 
 	return ret;
 }
@@ -1141,7 +1141,7 @@ static void tmc_disable_etr_sink(struct coresight_device *csdev)
 
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
 
-	dev_info(drvdata->dev, "TMC-ETR disabled\n");
+	dev_dbg(drvdata->dev, "TMC-ETR disabled\n");
 }
 
 static const struct coresight_ops_sink tmc_etr_sink_ops = {
diff --git a/drivers/hwtracing/coresight/coresight-tmc.c b/drivers/hwtracing/coresight/coresight-tmc.c
index 1b817ec1192c..ea249f0bcd73 100644
--- a/drivers/hwtracing/coresight/coresight-tmc.c
+++ b/drivers/hwtracing/coresight/coresight-tmc.c
@@ -81,7 +81,7 @@ static int tmc_read_prepare(struct tmc_drvdata *drvdata)
 	}
 
 	if (!ret)
-		dev_info(drvdata->dev, "TMC read start\n");
+		dev_dbg(drvdata->dev, "TMC read start\n");
 
 	return ret;
 }
@@ -103,7 +103,7 @@ static int tmc_read_unprepare(struct tmc_drvdata *drvdata)
 	}
 
 	if (!ret)
-		dev_info(drvdata->dev, "TMC read end\n");
+		dev_dbg(drvdata->dev, "TMC read end\n");
 
 	return ret;
 }
diff --git a/drivers/hwtracing/coresight/coresight-tpiu.c b/drivers/hwtracing/coresight/coresight-tpiu.c
index 459ef930d98c..ce0b84583861 100644
--- a/drivers/hwtracing/coresight/coresight-tpiu.c
+++ b/drivers/hwtracing/coresight/coresight-tpiu.c
@@ -74,7 +74,7 @@ static int tpiu_enable(struct coresight_device *csdev, u32 mode)
 
 	tpiu_enable_hw(drvdata);
 
-	dev_info(drvdata->dev, "TPIU enabled\n");
+	dev_dbg(drvdata->dev, "TPIU enabled\n");
 	return 0;
 }
 
@@ -100,7 +100,7 @@ static void tpiu_disable(struct coresight_device *csdev)
 
 	tpiu_disable_hw(drvdata);
 
-	dev_info(drvdata->dev, "TPIU disabled\n");
+	dev_dbg(drvdata->dev, "TPIU disabled\n");
 }
 
 static const struct coresight_ops_sink tpiu_sink_ops = {
-- 
2.7.4

[PATCH 19/44] coresight: perf: Remove reset_buffer call back for sinks

[Mathieu Poirier]

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

Right now we issue an update_buffer() and reset_buffer() call backs
in succession when we stop tracing an event. The update_buffer is
supposed to check the status of the buffer and make sure the ring buffer
is updated with the trace data. And we store information about the
size of the data collected only to be consumed by the reset_buffer
callback which always follows the update_buffer. This was originally
designed for handling future IPs which could trigger a buffer overflow
interrupt. This patch gets rid of the reset_buffer callback altogether
and performs the actions in update_buffer, making it return the size
collected. We can always add the support for handling the overflow
interrupt case later.

This removes some not-so pretty hack (storing the new head in the
size field for snapshot mode) and cleans it up a little bit.

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-etb10.c    | 56 +++++------------------
 drivers/hwtracing/coresight/coresight-etm-perf.c |  9 +---
 drivers/hwtracing/coresight/coresight-tmc-etf.c  | 58 +++++-------------------
 include/linux/coresight.h                        |  6 +--
 4 files changed, 26 insertions(+), 103 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-etb10.c b/drivers/hwtracing/coresight/coresight-etb10.c
index 3d4b6df32a06..dba75c905e57 100644
--- a/drivers/hwtracing/coresight/coresight-etb10.c
+++ b/drivers/hwtracing/coresight/coresight-etb10.c
@@ -319,37 +319,7 @@ static int etb_set_buffer(struct coresight_device *csdev,
 	return ret;
 }
 
-static unsigned long etb_reset_buffer(struct coresight_device *csdev,
-				      struct perf_output_handle *handle,
-				      void *sink_config)
-{
-	unsigned long size = 0;
-	struct cs_buffers *buf = sink_config;
-
-	if (buf) {
-		/*
-		 * In snapshot mode ->data_size holds the new address of the
-		 * ring buffer's head.  The size itself is the whole address
-		 * range since we want the latest information.
-		 */
-		if (buf->snapshot)
-			handle->head = local_xchg(&buf->data_size,
-						  buf->nr_pages << PAGE_SHIFT);
-
-		/*
-		 * Tell the tracer PMU how much we got in this run and if
-		 * something went wrong along the way.  Nobody else can use
-		 * this cs_buffers instance until we are done.  As such
-		 * resetting parameters here and squaring off with the ring
-		 * buffer API in the tracer PMU is fine.
-		 */
-		size = local_xchg(&buf->data_size, 0);
-	}
-
-	return size;
-}
-
-static void etb_update_buffer(struct coresight_device *csdev,
+static unsigned long etb_update_buffer(struct coresight_device *csdev,
 			      struct perf_output_handle *handle,
 			      void *sink_config)
 {
@@ -358,13 +328,13 @@ static void etb_update_buffer(struct coresight_device *csdev,
 	u8 *buf_ptr;
 	const u32 *barrier;
 	u32 read_ptr, write_ptr, capacity;
-	u32 status, read_data, to_read;
-	unsigned long offset;
+	u32 status, read_data;
+	unsigned long offset, to_read;
 	struct cs_buffers *buf = sink_config;
 	struct etb_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
 
 	if (!buf)
-		return;
+		return 0;
 
 	capacity = drvdata->buffer_depth * ETB_FRAME_SIZE_WORDS;
 
@@ -469,18 +439,17 @@ static void etb_update_buffer(struct coresight_device *csdev,
 	writel_relaxed(0x0, drvdata->base + ETB_RAM_WRITE_POINTER);
 
 	/*
-	 * In snapshot mode all we have to do is communicate to
-	 * perf_aux_output_end() the address of the current head.  In full
-	 * trace mode the same function expects a size to move rb->aux_head
-	 * forward.
+	 * In snapshot mode we have to update the handle->head to point
+	 * to the new location.
 	 */
-	if (buf->snapshot)
-		local_set(&buf->data_size, (cur * PAGE_SIZE) + offset);
-	else
-		local_add(to_read, &buf->data_size);
-
+	if (buf->snapshot) {
+		handle->head = (cur * PAGE_SIZE) + offset;
+		to_read = buf->nr_pages << PAGE_SHIFT;
+	}
 	etb_enable_hw(drvdata);
 	CS_LOCK(drvdata->base);
+
+	return to_read;
 }
 
 static const struct coresight_ops_sink etb_sink_ops = {
@@ -489,7 +458,6 @@ static const struct coresight_ops_sink etb_sink_ops = {
 	.alloc_buffer	= etb_alloc_buffer,
 	.free_buffer	= etb_free_buffer,
 	.set_buffer	= etb_set_buffer,
-	.reset_buffer	= etb_reset_buffer,
 	.update_buffer	= etb_update_buffer,
 };
 
diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c
index 6db76ce6ba5f..ad87441f65d7 100644
--- a/drivers/hwtracing/coresight/coresight-etm-perf.c
+++ b/drivers/hwtracing/coresight/coresight-etm-perf.c
@@ -369,15 +369,8 @@ static void etm_event_stop(struct perf_event *event, int mode)
 		if (!sink_ops(sink)->update_buffer)
 			return;
 
-		sink_ops(sink)->update_buffer(sink, handle,
+		size = sink_ops(sink)->update_buffer(sink, handle,
 					      event_data->snk_config);
-
-		if (!sink_ops(sink)->reset_buffer)
-			return;
-
-		size = sink_ops(sink)->reset_buffer(sink, handle,
-						    event_data->snk_config);
-
 		perf_aux_output_end(handle, size);
 	}
 
diff --git a/drivers/hwtracing/coresight/coresight-tmc-etf.c b/drivers/hwtracing/coresight/coresight-tmc-etf.c
index 434003a43346..31a98f915641 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etf.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etf.c
@@ -349,36 +349,7 @@ static int tmc_set_etf_buffer(struct coresight_device *csdev,
 	return ret;
 }
 
-static unsigned long tmc_reset_etf_buffer(struct coresight_device *csdev,
-					  struct perf_output_handle *handle,
-					  void *sink_config)
-{
-	long size = 0;
-	struct cs_buffers *buf = sink_config;
-
-	if (buf) {
-		/*
-		 * In snapshot mode ->data_size holds the new address of the
-		 * ring buffer's head.  The size itself is the whole address
-		 * range since we want the latest information.
-		 */
-		if (buf->snapshot)
-			handle->head = local_xchg(&buf->data_size,
-						  buf->nr_pages << PAGE_SHIFT);
-		/*
-		 * Tell the tracer PMU how much we got in this run and if
-		 * something went wrong along the way.  Nobody else can use
-		 * this cs_buffers instance until we are done.  As such
-		 * resetting parameters here and squaring off with the ring
-		 * buffer API in the tracer PMU is fine.
-		 */
-		size = local_xchg(&buf->data_size, 0);
-	}
-
-	return size;
-}
-
-static void tmc_update_etf_buffer(struct coresight_device *csdev,
+static unsigned long tmc_update_etf_buffer(struct coresight_device *csdev,
 				  struct perf_output_handle *handle,
 				  void *sink_config)
 {
@@ -387,17 +358,17 @@ static void tmc_update_etf_buffer(struct coresight_device *csdev,
 	const u32 *barrier;
 	u32 *buf_ptr;
 	u64 read_ptr, write_ptr;
-	u32 status, to_read;
-	unsigned long offset;
+	u32 status;
+	unsigned long offset, to_read;
 	struct cs_buffers *buf = sink_config;
 	struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
 
 	if (!buf)
-		return;
+		return 0;
 
 	/* This shouldn't happen */
 	if (WARN_ON_ONCE(drvdata->mode != CS_MODE_PERF))
-		return;
+		return 0;
 
 	CS_UNLOCK(drvdata->base);
 
@@ -486,18 +457,14 @@ static void tmc_update_etf_buffer(struct coresight_device *csdev,
 		}
 	}
 
-	/*
-	 * In snapshot mode all we have to do is communicate to
-	 * perf_aux_output_end() the address of the current head.  In full
-	 * trace mode the same function expects a size to move rb->aux_head
-	 * forward.
-	 */
-	if (buf->snapshot)
-		local_set(&buf->data_size, (cur * PAGE_SIZE) + offset);
-	else
-		local_add(to_read, &buf->data_size);
-
+	/* In snapshot mode we have to update the head */
+	if (buf->snapshot) {
+		handle->head = (cur * PAGE_SIZE) + offset;
+		to_read = buf->nr_pages << PAGE_SHIFT;
+	}
 	CS_LOCK(drvdata->base);
+
+	return to_read;
 }
 
 static const struct coresight_ops_sink tmc_etf_sink_ops = {
@@ -506,7 +473,6 @@ static const struct coresight_ops_sink tmc_etf_sink_ops = {
 	.alloc_buffer	= tmc_alloc_etf_buffer,
 	.free_buffer	= tmc_free_etf_buffer,
 	.set_buffer	= tmc_set_etf_buffer,
-	.reset_buffer	= tmc_reset_etf_buffer,
 	.update_buffer	= tmc_update_etf_buffer,
 };
 
diff --git a/include/linux/coresight.h b/include/linux/coresight.h
index 41e1f4333bf2..8e52682b1e90 100644
--- a/include/linux/coresight.h
+++ b/include/linux/coresight.h
@@ -186,7 +186,6 @@ struct coresight_device {
  * @alloc_buffer:	initialises perf's ring buffer for trace collection.
  * @free_buffer:	release memory allocated in @get_config.
  * @set_buffer:		initialises buffer mechanic before a trace session.
- * @reset_buffer:	finalises buffer mechanic after a trace session.
  * @update_buffer:	update buffer pointers after a trace session.
  */
 struct coresight_ops_sink {
@@ -198,10 +197,7 @@ struct coresight_ops_sink {
 	int (*set_buffer)(struct coresight_device *csdev,
 			  struct perf_output_handle *handle,
 			  void *sink_config);
-	unsigned long (*reset_buffer)(struct coresight_device *csdev,
-				      struct perf_output_handle *handle,
-				      void *sink_config);
-	void (*update_buffer)(struct coresight_device *csdev,
+	unsigned long (*update_buffer)(struct coresight_device *csdev,
 			      struct perf_output_handle *handle,
 			      void *sink_config);
 };
-- 
2.7.4

[PATCH 20/44] coresight: perf: Add helper to retrieve sink configuration

[Mathieu Poirier]

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

We can always find the sink configuration for a given perf_output_handle.
Add a helper to retrieve the sink configuration for a given
perf_output_handle. This will be used to get rid of the set_buffer()
call back.

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-etm-perf.c | 14 -------------
 drivers/hwtracing/coresight/coresight-etm-perf.h | 26 ++++++++++++++++++++++++
 2 files changed, 26 insertions(+), 14 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c
index ad87441f65d7..16b83d8b2ac2 100644
--- a/drivers/hwtracing/coresight/coresight-etm-perf.c
+++ b/drivers/hwtracing/coresight/coresight-etm-perf.c
@@ -23,20 +23,6 @@
 static struct pmu etm_pmu;
 static bool etm_perf_up;
 
-/**
- * struct etm_event_data - Coresight specifics associated to an event
- * @work:		Handle to free allocated memory outside IRQ context.
- * @mask:		Hold the CPU(s) this event was set for.
- * @snk_config:		The sink configuration.
- * @path:		An array of path, each slot for one CPU.
- */
-struct etm_event_data {
-	struct work_struct work;
-	cpumask_t mask;
-	void *snk_config;
-	struct list_head * __percpu *path;
-};
-
 static DEFINE_PER_CPU(struct perf_output_handle, ctx_handle);
 static DEFINE_PER_CPU(struct coresight_device *, csdev_src);
 
diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.h b/drivers/hwtracing/coresight/coresight-etm-perf.h
index 4197df4faf5e..da7d9336a15c 100644
--- a/drivers/hwtracing/coresight/coresight-etm-perf.h
+++ b/drivers/hwtracing/coresight/coresight-etm-perf.h
@@ -7,6 +7,7 @@
 #ifndef _CORESIGHT_ETM_PERF_H
 #define _CORESIGHT_ETM_PERF_H
 
+#include <linux/percpu-defs.h>
 #include "coresight-priv.h"
 
 struct coresight_device;
@@ -42,14 +43,39 @@ struct etm_filters {
 	bool			ssstatus;
 };
 
+/**
+ * struct etm_event_data - Coresight specifics associated to an event
+ * @work:		Handle to free allocated memory outside IRQ context.
+ * @mask:		Hold the CPU(s) this event was set for.
+ * @snk_config:		The sink configuration.
+ * @path:		An array of path, each slot for one CPU.
+ */
+struct etm_event_data {
+	struct work_struct work;
+	cpumask_t mask;
+	void *snk_config;
+	struct list_head * __percpu *path;
+};
 
 #ifdef CONFIG_CORESIGHT
 int etm_perf_symlink(struct coresight_device *csdev, bool link);
+static inline void *etm_perf_sink_config(struct perf_output_handle *handle)
+{
+	struct etm_event_data *data = perf_get_aux(handle);
 
+	if (data)
+		return data->snk_config;
+	return NULL;
+}
 #else
 static inline int etm_perf_symlink(struct coresight_device *csdev, bool link)
 { return -EINVAL; }
 
+static inline void *etm_perf_sink_config(struct perf_output_handle *handle)
+{
+	return NULL;
+}
+
 #endif /* CONFIG_CORESIGHT */
 
 #endif
-- 
2.7.4

[PATCH 21/44] coresight: perf: Remove set_buffer call back

[Mathieu Poirier]

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

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>
---
 drivers/hwtracing/coresight/coresight-etb10.c    | 32 ++++++++++++++++++------
 drivers/hwtracing/coresight/coresight-etm-perf.c |  9 ++-----
 drivers/hwtracing/coresight/coresight-priv.h     |  2 +-
 drivers/hwtracing/coresight/coresight-tmc-etf.c  | 28 ++++++++++++++-------
 drivers/hwtracing/coresight/coresight-tmc-etr.c  |  7 +++---
 drivers/hwtracing/coresight/coresight-tpiu.c     |  2 +-
 drivers/hwtracing/coresight/coresight.c          | 11 ++++----
 include/linux/coresight.h                        |  6 +----
 8 files changed, 59 insertions(+), 38 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-etb10.c b/drivers/hwtracing/coresight/coresight-etb10.c
index dba75c905e57..9fd77fdc1244 100644
--- a/drivers/hwtracing/coresight/coresight-etb10.c
+++ b/drivers/hwtracing/coresight/coresight-etb10.c
@@ -28,6 +28,7 @@
 
 
 #include "coresight-priv.h"
+#include "coresight-etm-perf.h"
 
 #define ETB_RAM_DEPTH_REG	0x004
 #define ETB_STATUS_REG		0x00c
@@ -90,6 +91,9 @@ struct etb_drvdata {
 	u32			trigger_cntr;
 };
 
+static int etb_set_buffer(struct coresight_device *csdev,
+			  struct perf_output_handle *handle);
+
 static unsigned int etb_get_buffer_depth(struct etb_drvdata *drvdata)
 {
 	u32 depth = 0;
@@ -131,12 +135,24 @@ static void etb_enable_hw(struct etb_drvdata *drvdata)
 	CS_LOCK(drvdata->base);
 }
 
-static int etb_enable(struct coresight_device *csdev, u32 mode)
+static int etb_enable(struct coresight_device *csdev, u32 mode, void *data)
 {
+	int ret = 0;
 	u32 val;
 	unsigned long flags;
 	struct etb_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
 
+	/*
+	 * We don't have an internal state to clean up if we fail to setup
+	 * the perf buffer. So we can perform the step before we turn the
+	 * ETB on and leave without cleaning up.
+	 */
+	if (mode == CS_MODE_PERF) {
+		ret = etb_set_buffer(csdev, (struct perf_output_handle *)data);
+		if (ret)
+			goto out;
+	}
+
 	val = local_cmpxchg(&drvdata->mode,
 			    CS_MODE_DISABLED, mode);
 	/*
@@ -160,8 +176,9 @@ static int etb_enable(struct coresight_device *csdev, u32 mode)
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
 
 out:
-	dev_dbg(drvdata->dev, "ETB enabled\n");
-	return 0;
+	if (!ret)
+		dev_dbg(drvdata->dev, "ETB enabled\n");
+	return ret;
 }
 
 static void etb_disable_hw(struct etb_drvdata *drvdata)
@@ -298,12 +315,14 @@ static void etb_free_buffer(void *config)
 }
 
 static int etb_set_buffer(struct coresight_device *csdev,
-			  struct perf_output_handle *handle,
-			  void *sink_config)
+			  struct perf_output_handle *handle)
 {
 	int ret = 0;
 	unsigned long head;
-	struct cs_buffers *buf = sink_config;
+	struct cs_buffers *buf = etm_perf_sink_config(handle);
+
+	if (!buf)
+		return -EINVAL;
 
 	/* wrap head around to the amount of space we have */
 	head = handle->head & ((buf->nr_pages << PAGE_SHIFT) - 1);
@@ -457,7 +476,6 @@ static const struct coresight_ops_sink etb_sink_ops = {
 	.disable	= etb_disable,
 	.alloc_buffer	= etb_alloc_buffer,
 	.free_buffer	= etb_free_buffer,
-	.set_buffer	= etb_set_buffer,
 	.update_buffer	= etb_update_buffer,
 };
 
diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c
index 16b83d8b2ac2..abe8249b893b 100644
--- a/drivers/hwtracing/coresight/coresight-etm-perf.c
+++ b/drivers/hwtracing/coresight/coresight-etm-perf.c
@@ -286,16 +286,11 @@ static void etm_event_start(struct perf_event *event, int flags)
 	path = etm_event_cpu_path(event_data, cpu);
 	/* We need a sink, no need to continue without one */
 	sink = coresight_get_sink(path);
-	if (WARN_ON_ONCE(!sink || !sink_ops(sink)->set_buffer))
-		goto fail_end_stop;
-
-	/* Configure the sink */
-	if (sink_ops(sink)->set_buffer(sink, handle,
-				       event_data->snk_config))
+	if (WARN_ON_ONCE(!sink))
 		goto fail_end_stop;
 
 	/* Nothing will happen without a path */
-	if (coresight_enable_path(path, CS_MODE_PERF))
+	if (coresight_enable_path(path, CS_MODE_PERF, handle))
 		goto fail_end_stop;
 
 	/* Tell the perf core the event is alive */
diff --git a/drivers/hwtracing/coresight/coresight-priv.h b/drivers/hwtracing/coresight/coresight-priv.h
index 1a6cf3589866..c11da5564a67 100644
--- a/drivers/hwtracing/coresight/coresight-priv.h
+++ b/drivers/hwtracing/coresight/coresight-priv.h
@@ -137,7 +137,7 @@ static inline void coresight_write_reg_pair(void __iomem *addr, u64 val,
 }
 
 void coresight_disable_path(struct list_head *path);
-int coresight_enable_path(struct list_head *path, u32 mode);
+int coresight_enable_path(struct list_head *path, u32 mode, void *sink_data);
 struct coresight_device *coresight_get_sink(struct list_head *path);
 struct coresight_device *coresight_get_enabled_sink(bool reset);
 struct list_head *coresight_build_path(struct coresight_device *csdev,
diff --git a/drivers/hwtracing/coresight/coresight-tmc-etf.c b/drivers/hwtracing/coresight/coresight-tmc-etf.c
index 31a98f915641..4156c95ce1bb 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etf.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etf.c
@@ -10,6 +10,10 @@
 #include <linux/slab.h>
 #include "coresight-priv.h"
 #include "coresight-tmc.h"
+#include "coresight-etm-perf.h"
+
+static int tmc_set_etf_buffer(struct coresight_device *csdev,
+			      struct perf_output_handle *handle);
 
 static void tmc_etb_enable_hw(struct tmc_drvdata *drvdata)
 {
@@ -182,11 +186,12 @@ static int tmc_enable_etf_sink_sysfs(struct coresight_device *csdev)
 	return ret;
 }
 
-static int tmc_enable_etf_sink_perf(struct coresight_device *csdev)
+static int tmc_enable_etf_sink_perf(struct coresight_device *csdev, void *data)
 {
 	int ret = 0;
 	unsigned long flags;
 	struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
+	struct perf_output_handle *handle = data;
 
 	spin_lock_irqsave(&drvdata->spinlock, flags);
 	if (drvdata->reading) {
@@ -204,15 +209,19 @@ static int tmc_enable_etf_sink_perf(struct coresight_device *csdev)
 		goto out;
 	}
 
-	drvdata->mode = CS_MODE_PERF;
-	tmc_etb_enable_hw(drvdata);
+	ret = tmc_set_etf_buffer(csdev, handle);
+	if (!ret) {
+		drvdata->mode = CS_MODE_PERF;
+		tmc_etb_enable_hw(drvdata);
+	}
 out:
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
 
 	return ret;
 }
 
-static int tmc_enable_etf_sink(struct coresight_device *csdev, u32 mode)
+static int tmc_enable_etf_sink(struct coresight_device *csdev,
+			       u32 mode, void *data)
 {
 	int ret;
 	struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
@@ -222,7 +231,7 @@ static int tmc_enable_etf_sink(struct coresight_device *csdev, u32 mode)
 		ret = tmc_enable_etf_sink_sysfs(csdev);
 		break;
 	case CS_MODE_PERF:
-		ret = tmc_enable_etf_sink_perf(csdev);
+		ret = tmc_enable_etf_sink_perf(csdev, data);
 		break;
 	/* We shouldn't be here */
 	default:
@@ -328,12 +337,14 @@ static void tmc_free_etf_buffer(void *config)
 }
 
 static int tmc_set_etf_buffer(struct coresight_device *csdev,
-			      struct perf_output_handle *handle,
-			      void *sink_config)
+			      struct perf_output_handle *handle)
 {
 	int ret = 0;
 	unsigned long head;
-	struct cs_buffers *buf = sink_config;
+	struct cs_buffers *buf = etm_perf_sink_config(handle);
+
+	if (!buf)
+		return -EINVAL;
 
 	/* wrap head around to the amount of space we have */
 	head = handle->head & ((buf->nr_pages << PAGE_SHIFT) - 1);
@@ -472,7 +483,6 @@ static const struct coresight_ops_sink tmc_etf_sink_ops = {
 	.disable	= tmc_disable_etf_sink,
 	.alloc_buffer	= tmc_alloc_etf_buffer,
 	.free_buffer	= tmc_free_etf_buffer,
-	.set_buffer	= tmc_set_etf_buffer,
 	.update_buffer	= tmc_update_etf_buffer,
 };
 
diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
index 5e9bb2f0e9c0..1aedfc3629c0 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
@@ -1103,19 +1103,20 @@ static int tmc_enable_etr_sink_sysfs(struct coresight_device *csdev)
 	return ret;
 }
 
-static int tmc_enable_etr_sink_perf(struct coresight_device *csdev)
+static int tmc_enable_etr_sink_perf(struct coresight_device *csdev, void *data)
 {
 	/* We don't support perf mode yet ! */
 	return -EINVAL;
 }
 
-static int tmc_enable_etr_sink(struct coresight_device *csdev, u32 mode)
+static int tmc_enable_etr_sink(struct coresight_device *csdev,
+			       u32 mode, void *data)
 {
 	switch (mode) {
 	case CS_MODE_SYSFS:
 		return tmc_enable_etr_sink_sysfs(csdev);
 	case CS_MODE_PERF:
-		return tmc_enable_etr_sink_perf(csdev);
+		return tmc_enable_etr_sink_perf(csdev, data);
 	}
 
 	/* We shouldn't be here */
diff --git a/drivers/hwtracing/coresight/coresight-tpiu.c b/drivers/hwtracing/coresight/coresight-tpiu.c
index ce0b84583861..b2f72a1fa402 100644
--- a/drivers/hwtracing/coresight/coresight-tpiu.c
+++ b/drivers/hwtracing/coresight/coresight-tpiu.c
@@ -68,7 +68,7 @@ static void tpiu_enable_hw(struct tpiu_drvdata *drvdata)
 	CS_LOCK(drvdata->base);
 }
 
-static int tpiu_enable(struct coresight_device *csdev, u32 mode)
+static int tpiu_enable(struct coresight_device *csdev, u32 mode, void *__unused)
 {
 	struct tpiu_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
 
diff --git a/drivers/hwtracing/coresight/coresight.c b/drivers/hwtracing/coresight/coresight.c
index 07382c55b31d..e73ca6af4765 100644
--- a/drivers/hwtracing/coresight/coresight.c
+++ b/drivers/hwtracing/coresight/coresight.c
@@ -128,7 +128,8 @@ static int coresight_find_link_outport(struct coresight_device *csdev,
 	return -ENODEV;
 }
 
-static int coresight_enable_sink(struct coresight_device *csdev, u32 mode)
+static int coresight_enable_sink(struct coresight_device *csdev,
+				 u32 mode, void *data)
 {
 	int ret;
 
@@ -137,7 +138,7 @@ static int coresight_enable_sink(struct coresight_device *csdev, u32 mode)
 	 * existing "mode" of operation.
 	 */
 	if (sink_ops(csdev)->enable) {
-		ret = sink_ops(csdev)->enable(csdev, mode);
+		ret = sink_ops(csdev)->enable(csdev, mode, data);
 		if (ret)
 			return ret;
 		csdev->enable = true;
@@ -315,7 +316,7 @@ void coresight_disable_path(struct list_head *path)
 	}
 }
 
-int coresight_enable_path(struct list_head *path, u32 mode)
+int coresight_enable_path(struct list_head *path, u32 mode, void *sink_data)
 {
 
 	int ret = 0;
@@ -340,7 +341,7 @@ int coresight_enable_path(struct list_head *path, u32 mode)
 
 		switch (type) {
 		case CORESIGHT_DEV_TYPE_SINK:
-			ret = coresight_enable_sink(csdev, mode);
+			ret = coresight_enable_sink(csdev, mode, sink_data);
 			/*
 			 * Sink is the first component turned on. If we
 			 * failed to enable the sink, there are no components
@@ -643,7 +644,7 @@ int coresight_enable(struct coresight_device *csdev)
 		goto out;
 	}
 
-	ret = coresight_enable_path(path, CS_MODE_SYSFS);
+	ret = coresight_enable_path(path, CS_MODE_SYSFS, NULL);
 	if (ret)
 		goto err_path;
 
diff --git a/include/linux/coresight.h b/include/linux/coresight.h
index 8e52682b1e90..53535821dc25 100644
--- a/include/linux/coresight.h
+++ b/include/linux/coresight.h
@@ -185,18 +185,14 @@ struct coresight_device {
  * @disable:		disables the sink.
  * @alloc_buffer:	initialises perf's ring buffer for trace collection.
  * @free_buffer:	release memory allocated in @get_config.
- * @set_buffer:		initialises buffer mechanic before a trace session.
  * @update_buffer:	update buffer pointers after a trace session.
  */
 struct coresight_ops_sink {
-	int (*enable)(struct coresight_device *csdev, u32 mode);
+	int (*enable)(struct coresight_device *csdev, u32 mode, void *data);
 	void (*disable)(struct coresight_device *csdev);
 	void *(*alloc_buffer)(struct coresight_device *csdev, int cpu,
 			      void **pages, int nr_pages, bool overwrite);
 	void (*free_buffer)(void *config);
-	int (*set_buffer)(struct coresight_device *csdev,
-			  struct perf_output_handle *handle,
-			  void *sink_config);
 	unsigned long (*update_buffer)(struct coresight_device *csdev,
 			      struct perf_output_handle *handle,
 			      void *sink_config);
-- 
2.7.4

[PATCH 22/44] coresight: etm-perf: Add support for ETR backend

[Mathieu Poirier]

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

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>
---
 drivers/hwtracing/coresight/coresight-tmc-etr.c | 248 +++++++++++++++++++++++-
 drivers/hwtracing/coresight/coresight-tmc.h     |   2 +
 2 files changed, 248 insertions(+), 2 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
index 1aedfc3629c0..56fea4ff947e 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
@@ -10,6 +10,7 @@
 #include <linux/slab.h>
 #include <linux/vmalloc.h>
 #include "coresight-catu.h"
+#include "coresight-etm-perf.h"
 #include "coresight-priv.h"
 #include "coresight-tmc.h"
 
@@ -21,6 +22,28 @@ struct etr_flat_buf {
 };
 
 /*
+ * etr_perf_buffer - Perf buffer used for ETR
+ * @etr_buf		- Actual buffer used by the ETR
+ * @snaphost		- Perf session mode
+ * @head		- handle->head at the beginning of the session.
+ * @nr_pages		- Number of pages in the ring buffer.
+ * @pages		- Array of Pages in the ring buffer.
+ */
+struct etr_perf_buffer {
+	struct etr_buf		*etr_buf;
+	bool			snapshot;
+	unsigned long		head;
+	int			nr_pages;
+	void			**pages;
+};
+
+/* Convert the perf index to an offset within the ETR buffer */
+#define PERF_IDX2OFF(idx, buf)	((idx) % ((buf)->nr_pages << PAGE_SHIFT))
+
+/* Lower limit for ETR hardware buffer */
+#define TMC_ETR_PERF_MIN_BUF_SIZE	SZ_1M
+
+/*
  * The TMC ETR SG has a page size of 4K. The SG table contains pointers
  * to 4KB buffers. However, the OS may use a PAGE_SIZE different from
  * 4K (i.e, 16KB or 64KB). This implies that a single OS page could
@@ -1103,10 +1126,228 @@ static int tmc_enable_etr_sink_sysfs(struct coresight_device *csdev)
 	return ret;
 }
 
+/*
+ * tmc_etr_setup_perf_buf: Allocate ETR buffer for use by perf.
+ * The size of the hardware buffer is dependent on the size configured
+ * via sysfs and the perf ring buffer size. We prefer to allocate the
+ * largest possible size, scaling down the size by half until it
+ * reaches a minimum limit (1M), beyond which we give up.
+ */
+static struct etr_perf_buffer *
+tmc_etr_setup_perf_buf(struct tmc_drvdata *drvdata, int node, int nr_pages,
+		       void **pages, bool snapshot)
+{
+	struct etr_buf *etr_buf;
+	struct etr_perf_buffer *etr_perf;
+	unsigned long size;
+
+	etr_perf = kzalloc_node(sizeof(*etr_perf), GFP_KERNEL, node);
+	if (!etr_perf)
+		return ERR_PTR(-ENOMEM);
+
+	/*
+	 * Try to match the perf ring buffer size if it is larger
+	 * than the size requested via sysfs.
+	 */
+	if ((nr_pages << PAGE_SHIFT) > drvdata->size) {
+		etr_buf = tmc_alloc_etr_buf(drvdata, (nr_pages << PAGE_SHIFT),
+					    0, node, NULL);
+		if (!IS_ERR(etr_buf))
+			goto done;
+	}
+
+	/*
+	 * Else switch to configured size for this ETR
+	 * and scale down until we hit the minimum limit.
+	 */
+	size = drvdata->size;
+	do {
+		etr_buf = tmc_alloc_etr_buf(drvdata, size, 0, node, NULL);
+		if (!IS_ERR(etr_buf))
+			goto done;
+		size /= 2;
+	} while (size >= TMC_ETR_PERF_MIN_BUF_SIZE);
+
+	kfree(etr_perf);
+	return ERR_PTR(-ENOMEM);
+
+done:
+	etr_perf->etr_buf = etr_buf;
+	return etr_perf;
+}
+
+
+static void *tmc_alloc_etr_buffer(struct coresight_device *csdev,
+				  int cpu, void **pages, int nr_pages,
+				  bool snapshot)
+{
+	struct etr_perf_buffer *etr_perf;
+	struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
+
+	if (cpu == -1)
+		cpu = smp_processor_id();
+
+	etr_perf = tmc_etr_setup_perf_buf(drvdata, cpu_to_node(cpu),
+					  nr_pages, pages, snapshot);
+	if (IS_ERR(etr_perf)) {
+		dev_dbg(drvdata->dev, "Unable to allocate ETR buffer\n");
+		return NULL;
+	}
+
+	etr_perf->snapshot = snapshot;
+	etr_perf->nr_pages = nr_pages;
+	etr_perf->pages = pages;
+
+	return etr_perf;
+}
+
+static void tmc_free_etr_buffer(void *config)
+{
+	struct etr_perf_buffer *etr_perf = config;
+
+	if (etr_perf->etr_buf)
+		tmc_free_etr_buf(etr_perf->etr_buf);
+	kfree(etr_perf);
+}
+
+/*
+ * tmc_etr_sync_perf_buffer: Copy the actual trace data from the hardware
+ * buffer to the perf ring buffer.
+ */
+static void tmc_etr_sync_perf_buffer(struct etr_perf_buffer *etr_perf)
+{
+	long bytes, to_copy;
+	long pg_idx, pg_offset, src_offset;
+	unsigned long head = etr_perf->head;
+	char **dst_pages, *src_buf;
+	struct etr_buf *etr_buf = etr_perf->etr_buf;
+
+	head = etr_perf->head;
+	pg_idx = head >> PAGE_SHIFT;
+	pg_offset = head & (PAGE_SIZE - 1);
+	dst_pages = (char **)etr_perf->pages;
+	src_offset = etr_buf->offset;
+	to_copy = etr_buf->len;
+
+	while (to_copy > 0) {
+		/*
+		 * In one iteration, we can copy minimum of :
+		 *  1) what is available in the source buffer,
+		 *  2) what is available in the source buffer, before it
+		 *     wraps around.
+		 *  3) what is available in the destination page.
+		 * in one iteration.
+		 */
+		bytes = tmc_etr_buf_get_data(etr_buf, src_offset, to_copy,
+					     &src_buf);
+		if (WARN_ON_ONCE(bytes <= 0))
+			break;
+		bytes = min(bytes, (long)(PAGE_SIZE - pg_offset));
+
+		memcpy(dst_pages[pg_idx] + pg_offset, src_buf, bytes);
+
+		to_copy -= bytes;
+
+		/* Move destination pointers */
+		pg_offset += bytes;
+		if (pg_offset == PAGE_SIZE) {
+			pg_offset = 0;
+			if (++pg_idx == etr_perf->nr_pages)
+				pg_idx = 0;
+		}
+
+		/* Move source pointers */
+		src_offset += bytes;
+		if (src_offset >= etr_buf->size)
+			src_offset -= etr_buf->size;
+	}
+}
+
+/*
+ * tmc_update_etr_buffer : Update the perf ring buffer with the
+ * available trace data. We use software double buffering at the moment.
+ *
+ * TODO: Add support for reusing the perf ring buffer.
+ */
+static unsigned long
+tmc_update_etr_buffer(struct coresight_device *csdev,
+		      struct perf_output_handle *handle,
+		      void *config)
+{
+	bool lost = false;
+	unsigned long flags, size = 0;
+	struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
+	struct etr_perf_buffer *etr_perf = config;
+	struct etr_buf *etr_buf = etr_perf->etr_buf;
+
+	spin_lock_irqsave(&drvdata->spinlock, flags);
+	if (WARN_ON(drvdata->perf_data != etr_perf)) {
+		lost = true;
+		spin_unlock_irqrestore(&drvdata->spinlock, flags);
+		goto out;
+	}
+
+	CS_UNLOCK(drvdata->base);
+
+	tmc_flush_and_stop(drvdata);
+	tmc_sync_etr_buf(drvdata);
+
+	CS_LOCK(drvdata->base);
+	/* Reset perf specific data */
+	drvdata->perf_data = NULL;
+	spin_unlock_irqrestore(&drvdata->spinlock, flags);
+
+	size = etr_buf->len;
+	tmc_etr_sync_perf_buffer(etr_perf);
+
+	/*
+	 * Update handle->head in snapshot mode. Also update the size to the
+	 * hardware buffer size if there was an overflow.
+	 */
+	if (etr_perf->snapshot) {
+		handle->head += size;
+		if (etr_buf->full)
+			size = etr_buf->size;
+	}
+
+	lost |= etr_buf->full;
+out:
+	if (lost)
+		perf_aux_output_flag(handle, PERF_AUX_FLAG_TRUNCATED);
+	return size;
+}
+
 static int tmc_enable_etr_sink_perf(struct coresight_device *csdev, void *data)
 {
-	/* We don't support perf mode yet ! */
-	return -EINVAL;
+	int rc = 0;
+	unsigned long flags;
+	struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
+	struct perf_output_handle *handle = data;
+	struct etr_perf_buffer *etr_perf = etm_perf_sink_config(handle);
+
+	spin_lock_irqsave(&drvdata->spinlock, flags);
+	/*
+	 * There can be only one writer per sink in perf mode. If the sink
+	 * is already open in SYSFS mode, we can't use it.
+	 */
+	if (drvdata->mode != CS_MODE_DISABLED || WARN_ON(drvdata->perf_data)) {
+		rc = -EBUSY;
+		goto unlock_out;
+	}
+
+	if (WARN_ON(!etr_perf || !etr_perf->etr_buf)) {
+		rc = -EINVAL;
+		goto unlock_out;
+	}
+
+	etr_perf->head = PERF_IDX2OFF(handle->head, etr_perf);
+	drvdata->perf_data = etr_perf;
+	drvdata->mode = CS_MODE_PERF;
+	tmc_etr_enable_hw(drvdata, etr_perf->etr_buf);
+
+unlock_out:
+	spin_unlock_irqrestore(&drvdata->spinlock, flags);
+	return rc;
 }
 
 static int tmc_enable_etr_sink(struct coresight_device *csdev,
@@ -1148,6 +1389,9 @@ static void tmc_disable_etr_sink(struct coresight_device *csdev)
 static const struct coresight_ops_sink tmc_etr_sink_ops = {
 	.enable		= tmc_enable_etr_sink,
 	.disable	= tmc_disable_etr_sink,
+	.alloc_buffer	= tmc_alloc_etr_buffer,
+	.update_buffer	= tmc_update_etr_buffer,
+	.free_buffer	= tmc_free_etr_buffer,
 };
 
 const struct coresight_ops tmc_etr_cs_ops = {
diff --git a/drivers/hwtracing/coresight/coresight-tmc.h b/drivers/hwtracing/coresight/coresight-tmc.h
index 872f63e3651b..487c53701e9c 100644
--- a/drivers/hwtracing/coresight/coresight-tmc.h
+++ b/drivers/hwtracing/coresight/coresight-tmc.h
@@ -170,6 +170,7 @@ struct etr_buf {
  * @trigger_cntr: amount of words to store after a trigger.
  * @etr_caps:	Bitmask of capabilities of the TMC ETR, inferred from the
  *		device configuration register (DEVID)
+ * @perf_data:	PERF buffer for ETR.
  * @sysfs_data:	SYSFS buffer for ETR.
  */
 struct tmc_drvdata {
@@ -191,6 +192,7 @@ struct tmc_drvdata {
 	u32			trigger_cntr;
 	u32			etr_caps;
 	struct etr_buf		*sysfs_buf;
+	void			*perf_data;
 };
 
 struct etr_buf_operations {
-- 
2.7.4

[PATCH 23/44] coresight: etb10: Refactor etb_drvdata::mode handling

[Mathieu Poirier]

This patch moves the etb_drvdata::mode from a locat_t to a simple u32,
as it is for the ETF and ETR drivers.  This streamlines the code and adds
commonality with the other drivers when dealing with similar operations.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
---
 drivers/hwtracing/coresight/coresight-etb10.c | 62 +++++++++++++++------------
 1 file changed, 34 insertions(+), 28 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-etb10.c b/drivers/hwtracing/coresight/coresight-etb10.c
index 9fd77fdc1244..69287163ce4e 100644
--- a/drivers/hwtracing/coresight/coresight-etb10.c
+++ b/drivers/hwtracing/coresight/coresight-etb10.c
@@ -5,7 +5,6 @@
  * Description: CoreSight Embedded Trace Buffer driver
  */
 
-#include <asm/local.h>
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/types.h>
@@ -72,8 +71,8 @@
  * @miscdev:	specifics to handle "/dev/xyz.etb" entry.
  * @spinlock:	only one at a time pls.
  * @reading:	synchronise user space access to etb buffer.
- * @mode:	this ETB is being used.
  * @buf:	area of memory where ETB buffer content gets sent.
+ * @mode:	this ETB is being used.
  * @buffer_depth: size of @buf.
  * @trigger_cntr: amount of words to store after a trigger.
  */
@@ -85,8 +84,8 @@ struct etb_drvdata {
 	struct miscdevice	miscdev;
 	spinlock_t		spinlock;
 	local_t			reading;
-	local_t			mode;
 	u8			*buf;
+	u32			mode;
 	u32			buffer_depth;
 	u32			trigger_cntr;
 };
@@ -138,44 +137,48 @@ static void etb_enable_hw(struct etb_drvdata *drvdata)
 static int etb_enable(struct coresight_device *csdev, u32 mode, void *data)
 {
 	int ret = 0;
-	u32 val;
 	unsigned long flags;
 	struct etb_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
 
-	/*
-	 * We don't have an internal state to clean up if we fail to setup
-	 * the perf buffer. So we can perform the step before we turn the
-	 * ETB on and leave without cleaning up.
-	 */
-	if (mode == CS_MODE_PERF) {
-		ret = etb_set_buffer(csdev, (struct perf_output_handle *)data);
-		if (ret)
-			goto out;
-	}
+	spin_lock_irqsave(&drvdata->spinlock, flags);
 
-	val = local_cmpxchg(&drvdata->mode,
-			    CS_MODE_DISABLED, mode);
 	/*
 	 * When accessing from Perf, a HW buffer can be handled
 	 * by a single trace entity.  In sysFS mode many tracers
 	 * can be logging to the same HW buffer.
 	 */
-	if (val == CS_MODE_PERF)
-		return -EBUSY;
+	if (drvdata->mode == CS_MODE_PERF) {
+		ret = -EBUSY;
+		goto out;
+	}
 
 	/* Don't let perf disturb sysFS sessions */
-	if (val == CS_MODE_SYSFS && mode == CS_MODE_PERF)
-		return -EBUSY;
+	if (drvdata->mode == CS_MODE_SYSFS && mode == CS_MODE_PERF) {
+		ret = -EBUSY;
+		goto out;
+	}
 
 	/* Nothing to do, the tracer is already enabled. */
-	if (val == CS_MODE_SYSFS)
+	if (drvdata->mode == CS_MODE_SYSFS && mode == CS_MODE_SYSFS)
 		goto out;
 
-	spin_lock_irqsave(&drvdata->spinlock, flags);
+	/*
+	 * We don't have an internal state to clean up if we fail to setup
+	 * the perf buffer. So we can perform the step before we turn the
+	 * ETB on and leave without cleaning up.
+	 */
+	if (mode == CS_MODE_PERF) {
+		ret = etb_set_buffer(csdev, (struct perf_output_handle *)data);
+		if (ret)
+			goto out;
+	}
+
+	drvdata->mode = mode;
 	etb_enable_hw(drvdata);
-	spin_unlock_irqrestore(&drvdata->spinlock, flags);
 
 out:
+	spin_unlock_irqrestore(&drvdata->spinlock, flags);
+
 	if (!ret)
 		dev_dbg(drvdata->dev, "ETB enabled\n");
 	return ret;
@@ -277,11 +280,14 @@ static void etb_disable(struct coresight_device *csdev)
 	unsigned long flags;
 
 	spin_lock_irqsave(&drvdata->spinlock, flags);
-	etb_disable_hw(drvdata);
-	etb_dump_hw(drvdata);
-	spin_unlock_irqrestore(&drvdata->spinlock, flags);
 
-	local_set(&drvdata->mode, CS_MODE_DISABLED);
+	/* Disable the ETB only if it needs to */
+	if (drvdata->mode != CS_MODE_DISABLED) {
+		etb_disable_hw(drvdata);
+		etb_dump_hw(drvdata);
+		drvdata->mode = CS_MODE_DISABLED;
+	}
+	spin_unlock_irqrestore(&drvdata->spinlock, flags);
 
 	dev_dbg(drvdata->dev, "ETB disabled\n");
 }
@@ -488,7 +494,7 @@ static void etb_dump(struct etb_drvdata *drvdata)
 	unsigned long flags;
 
 	spin_lock_irqsave(&drvdata->spinlock, flags);
-	if (local_read(&drvdata->mode) == CS_MODE_SYSFS) {
+	if (drvdata->mode == CS_MODE_SYSFS) {
 		etb_disable_hw(drvdata);
 		etb_dump_hw(drvdata);
 		etb_enable_hw(drvdata);
-- 
2.7.4

[PATCH 24/44] coresight: etb10: Splitting function etb_enable()

[Mathieu Poirier]

Up until now the relative simplicity of enabling the ETB made it
possible to accommodate processing for both sysFS and perf methods.
But work on claimtags and CPU-wide trace scenarios is adding some
complexity, making the current code messy and hard to maintain.

As such follow what has been done for ETF and ETR components and split
function etb_enable() so that processing for both API can be done
cleanly.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
---
 drivers/hwtracing/coresight/coresight-etb10.c | 73 +++++++++++++++++++--------
 1 file changed, 52 insertions(+), 21 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-etb10.c b/drivers/hwtracing/coresight/coresight-etb10.c
index 69287163ce4e..08fa660098f8 100644
--- a/drivers/hwtracing/coresight/coresight-etb10.c
+++ b/drivers/hwtracing/coresight/coresight-etb10.c
@@ -134,7 +134,7 @@ static void etb_enable_hw(struct etb_drvdata *drvdata)
 	CS_LOCK(drvdata->base);
 }
 
-static int etb_enable(struct coresight_device *csdev, u32 mode, void *data)
+static int etb_enable_sysfs(struct coresight_device *csdev)
 {
 	int ret = 0;
 	unsigned long flags;
@@ -142,48 +142,79 @@ static int etb_enable(struct coresight_device *csdev, u32 mode, void *data)
 
 	spin_lock_irqsave(&drvdata->spinlock, flags);
 
-	/*
-	 * When accessing from Perf, a HW buffer can be handled
-	 * by a single trace entity.  In sysFS mode many tracers
-	 * can be logging to the same HW buffer.
-	 */
+	/* Don't messup with perf sessions. */
 	if (drvdata->mode == CS_MODE_PERF) {
 		ret = -EBUSY;
 		goto out;
 	}
 
-	/* Don't let perf disturb sysFS sessions */
-	if (drvdata->mode == CS_MODE_SYSFS && mode == CS_MODE_PERF) {
-		ret = -EBUSY;
+	/* Nothing to do, the tracer is already enabled. */
+	if (drvdata->mode == CS_MODE_SYSFS)
 		goto out;
-	}
 
-	/* Nothing to do, the tracer is already enabled. */
-	if (drvdata->mode == CS_MODE_SYSFS && mode == CS_MODE_SYSFS)
+	drvdata->mode = CS_MODE_SYSFS;
+	etb_enable_hw(drvdata);
+
+out:
+	spin_unlock_irqrestore(&drvdata->spinlock, flags);
+	return ret;
+}
+
+static int etb_enable_perf(struct coresight_device *csdev, void *data)
+{
+	int ret = 0;
+	unsigned long flags;
+	struct etb_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
+
+	spin_lock_irqsave(&drvdata->spinlock, flags);
+
+	/* No need to continue if the component is already in use. */
+	if (drvdata->mode != CS_MODE_DISABLED) {
+		ret = -EBUSY;
 		goto out;
+	}
 
 	/*
 	 * We don't have an internal state to clean up if we fail to setup
 	 * the perf buffer. So we can perform the step before we turn the
 	 * ETB on and leave without cleaning up.
 	 */
-	if (mode == CS_MODE_PERF) {
-		ret = etb_set_buffer(csdev, (struct perf_output_handle *)data);
-		if (ret)
-			goto out;
-	}
+	ret = etb_set_buffer(csdev, (struct perf_output_handle *)data);
+	if (ret)
+		goto out;
 
-	drvdata->mode = mode;
+	drvdata->mode = CS_MODE_PERF;
 	etb_enable_hw(drvdata);
 
 out:
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
-
-	if (!ret)
-		dev_dbg(drvdata->dev, "ETB enabled\n");
 	return ret;
 }
 
+static int etb_enable(struct coresight_device *csdev, u32 mode, void *data)
+{
+	int ret;
+	struct etb_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
+
+	switch (mode) {
+	case CS_MODE_SYSFS:
+		ret = etb_enable_sysfs(csdev);
+		break;
+	case CS_MODE_PERF:
+		ret = etb_enable_perf(csdev, data);
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	if (ret)
+		return ret;
+
+	dev_dbg(drvdata->dev, "ETB enabled\n");
+	return 0;
+}
+
 static void etb_disable_hw(struct etb_drvdata *drvdata)
 {
 	u32 ffcr;
-- 
2.7.4

[PATCH 25/44] coresight: etm4x: Configure EL2 exception level when kernel is running in HYP

[Mathieu Poirier]

From: Tomasz Nowicki <tnowicki@caviumnetworks.com>

For non-VHE systems host kernel runs at EL1 and jumps to EL2 whenever
hypervisor code should be executed. In this case ETM4x driver must
restrict configuration to EL1 when it setups kernel tracing.
However, there is no separate hypervisor privilege level when VHE
is enabled, the host kernel runs at EL2.

This patch fixes configuration of TRCACATRn register for VHE systems
so that ETM_EXLEVEL_NS_HYP bit is used instead of ETM_EXLEVEL_NS_OS
to on/off kernel tracing. At the same time, it moves common code
to new helper.

Signed-off-by: Tomasz Nowicki <tnowicki@caviumnetworks.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
 drivers/hwtracing/coresight/coresight-etm4x.c | 40 +++++++++++++--------------
 1 file changed, 20 insertions(+), 20 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c
index c1dcc7c289a5..b7379e9cfb30 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x.c
@@ -28,6 +28,7 @@
 #include <linux/pm_runtime.h>
 #include <asm/sections.h>
 #include <asm/local.h>
+#include <asm/virt.h>
 
 #include "coresight-etm4x.h"
 #include "coresight-etm-perf.h"
@@ -605,7 +606,7 @@ static void etm4_set_default_config(struct etmv4_config *config)
 	config->vinst_ctrl |= BIT(0);
 }
 
-static u64 etm4_get_access_type(struct etmv4_config *config)
+static u64 etm4_get_ns_access_type(struct etmv4_config *config)
 {
 	u64 access_type = 0;
 
@@ -616,17 +617,26 @@ static u64 etm4_get_access_type(struct etmv4_config *config)
 	 *   Bit[13] Exception level 1 - OS
 	 *   Bit[14] Exception level 2 - Hypervisor
 	 *   Bit[15] Never implemented
-	 *
-	 * Always stay away from hypervisor mode.
 	 */
-	access_type = ETM_EXLEVEL_NS_HYP;
-
-	if (config->mode & ETM_MODE_EXCL_KERN)
-		access_type |= ETM_EXLEVEL_NS_OS;
+	if (!is_kernel_in_hyp_mode()) {
+		/* Stay away from hypervisor mode for non-VHE */
+		access_type =  ETM_EXLEVEL_NS_HYP;
+		if (config->mode & ETM_MODE_EXCL_KERN)
+			access_type |= ETM_EXLEVEL_NS_OS;
+	} else if (config->mode & ETM_MODE_EXCL_KERN) {
+		access_type = ETM_EXLEVEL_NS_HYP;
+	}
 
 	if (config->mode & ETM_MODE_EXCL_USER)
 		access_type |= ETM_EXLEVEL_NS_APP;
 
+	return access_type;
+}
+
+static u64 etm4_get_access_type(struct etmv4_config *config)
+{
+	u64 access_type = etm4_get_ns_access_type(config);
+
 	/*
 	 * EXLEVEL_S, bits[11:8], don't trace anything happening
 	 * in secure state.
@@ -880,20 +890,10 @@ void etm4_config_trace_mode(struct etmv4_config *config)
 
 	addr_acc = config->addr_acc[ETM_DEFAULT_ADDR_COMP];
 	/* clear default config */
-	addr_acc &= ~(ETM_EXLEVEL_NS_APP | ETM_EXLEVEL_NS_OS);
+	addr_acc &= ~(ETM_EXLEVEL_NS_APP | ETM_EXLEVEL_NS_OS |
+		      ETM_EXLEVEL_NS_HYP);
 
-	/*
-	 * EXLEVEL_NS, bits[15:12]
-	 * The Exception levels are:
-	 *   Bit[12] Exception level 0 - Application
-	 *   Bit[13] Exception level 1 - OS
-	 *   Bit[14] Exception level 2 - Hypervisor
-	 *   Bit[15] Never implemented
-	 */
-	if (mode & ETM_MODE_EXCL_KERN)
-		addr_acc |= ETM_EXLEVEL_NS_OS;
-	else
-		addr_acc |= ETM_EXLEVEL_NS_APP;
+	addr_acc |= etm4_get_ns_access_type(config);
 
 	config->addr_acc[ETM_DEFAULT_ADDR_COMP] = addr_acc;
 	config->addr_acc[ETM_DEFAULT_ADDR_COMP + 1] = addr_acc;
-- 
2.7.4

[PATCH 26/44] coresight: tmc: Refactor loops in etb dump

[Mathieu Poirier]

From: Leo Yan <leo.yan@linaro.org>

In ETB dump function tmc_etb_dump_hw() it has nested loops.  The second
level loop is to iterate index in the range [0 .. drvdata->memwidth);
but the index isn't really used in the code, thus the second level
loop is useless.

This patch is to remove the second level loop; the refactor also reduces
indentation and we can use 'break' to replace 'goto' tag.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
 drivers/hwtracing/coresight/coresight-tmc-etf.c | 17 +++++++----------
 1 file changed, 7 insertions(+), 10 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-tmc-etf.c b/drivers/hwtracing/coresight/coresight-tmc-etf.c
index 4156c95ce1bb..4bf3bfd7c078 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etf.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etf.c
@@ -38,23 +38,20 @@ static void tmc_etb_dump_hw(struct tmc_drvdata *drvdata)
 {
 	char *bufp;
 	u32 read_data, lost;
-	int i;
 
 	/* Check if the buffer wrapped around. */
 	lost = readl_relaxed(drvdata->base + TMC_STS) & TMC_STS_FULL;
 	bufp = drvdata->buf;
 	drvdata->len = 0;
 	while (1) {
-		for (i = 0; i < drvdata->memwidth; i++) {
-			read_data = readl_relaxed(drvdata->base + TMC_RRD);
-			if (read_data == 0xFFFFFFFF)
-				goto done;
-			memcpy(bufp, &read_data, 4);
-			bufp += 4;
-			drvdata->len += 4;
-		}
+		read_data = readl_relaxed(drvdata->base + TMC_RRD);
+		if (read_data == 0xFFFFFFFF)
+			break;
+		memcpy(bufp, &read_data, 4);
+		bufp += 4;
+		drvdata->len += 4;
 	}
-done:
+
 	if (lost)
 		coresight_insert_barrier_packet(drvdata->buf);
 	return;
-- 
2.7.4

[PATCH 27/44] coresight: tmc: Fix byte-address alignment for RRP

[Mathieu Poirier]

From: Leo Yan <leo.yan@linaro.org>

From the comment in the code, it claims the requirement for byte-address
alignment for RRP register: 'for 32-bit, 64-bit and 128-bit wide trace
memory, the four LSBs must be 0s. For 256-bit wide trace memory, the
five LSBs must be 0s'.  This isn't consistent with the program, the
program sets five LSBs as zeros for 32/64/128-bit wide trace memory and
set six LSBs zeros for 256-bit wide trace memory.

After checking with the CoreSight Trace Memory Controller technical
reference manual (ARM DDI 0461B, section 3.3.4 RAM Read Pointer
Register), it proves the comment is right and the program does wrong
setting.

This patch fixes byte-address alignment for RRP by following correct
definition in the technical reference manual.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
 drivers/hwtracing/coresight/coresight-tmc-etf.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-tmc-etf.c b/drivers/hwtracing/coresight/coresight-tmc-etf.c
index 4bf3bfd7c078..b54a3db13fee 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etf.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etf.c
@@ -417,10 +417,10 @@ static unsigned long tmc_update_etf_buffer(struct coresight_device *csdev,
 		case TMC_MEM_INTF_WIDTH_32BITS:
 		case TMC_MEM_INTF_WIDTH_64BITS:
 		case TMC_MEM_INTF_WIDTH_128BITS:
-			mask = GENMASK(31, 5);
+			mask = GENMASK(31, 4);
 			break;
 		case TMC_MEM_INTF_WIDTH_256BITS:
-			mask = GENMASK(31, 6);
+			mask = GENMASK(31, 5);
 			break;
 		}
 
-- 
2.7.4

[PATCH 28/44] coresight: Handle failures in enabling a trace path

[Mathieu Poirier]

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

coresight_enable_path() enables the components in a trace
path from a given source to a sink, excluding the source.
The operation is performed in the reverse order; the sink
first and then backwards in the list. However, if we encounter
an error in enabling any of the component, we simply disable
all the components in the given path irrespective of whether
we enabled some of the components in the enable iteration.
This could interfere with another trace session if one of the
link devices is turned off (e.g, TMC-ETF). So, we need to
make sure that we only disable those components which were
actually enabled from the iteration.

This patch achieves the same by refactoring the coresight_disable_path
to accept a "node" to start from in the forward order, which can
then be used from the error path of coresight_enable_path().
With this change, we don't issue a disable call back for a component
which didn't get enabled. This change of behavior triggers
a bug in coresight_enable_link(), where we leave the refcount
on the device and will prevent the device from being enabled
forever. So, we also drop the refcount in the coresight_enable_link()
if the operation failed.

Also, with the refactoring, we always start after the first node (which
is the "SOURCE" device) for disabling the entire path. This implies,
we must not find a "SOURCE" in the middle of the path. Hence, added
a WARN_ON() to make sure the paths we get are sane, rather than
simply ignoring them.

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.c | 32 ++++++++++++++++++++++++++------
 1 file changed, 26 insertions(+), 6 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight.c b/drivers/hwtracing/coresight/coresight.c
index e73ca6af4765..f4f50753cf75 100644
--- a/drivers/hwtracing/coresight/coresight.c
+++ b/drivers/hwtracing/coresight/coresight.c
@@ -187,8 +187,10 @@ static int coresight_enable_link(struct coresight_device *csdev,
 	if (atomic_inc_return(&csdev->refcnt[refport]) == 1) {
 		if (link_ops(csdev)->enable) {
 			ret = link_ops(csdev)->enable(csdev, inport, outport);
-			if (ret)
+			if (ret) {
+				atomic_dec(&csdev->refcnt[refport]);
 				return ret;
+			}
 		}
 	}
 
@@ -277,13 +279,21 @@ static bool coresight_disable_source(struct coresight_device *csdev)
 	return !csdev->enable;
 }
 
-void coresight_disable_path(struct list_head *path)
+/*
+ * coresight_disable_path_from : Disable components in the given path beyond
+ * @nd in the list. If @nd is NULL, all the components, except the SOURCE are
+ * disabled.
+ */
+static void coresight_disable_path_from(struct list_head *path,
+					struct coresight_node *nd)
 {
 	u32 type;
-	struct coresight_node *nd;
 	struct coresight_device *csdev, *parent, *child;
 
-	list_for_each_entry(nd, path, link) {
+	if (!nd)
+		nd = list_first_entry(path, struct coresight_node, link);
+
+	list_for_each_entry_continue(nd, path, link) {
 		csdev = nd->csdev;
 		type = csdev->type;
 
@@ -303,7 +313,12 @@ void coresight_disable_path(struct list_head *path)
 			coresight_disable_sink(csdev);
 			break;
 		case CORESIGHT_DEV_TYPE_SOURCE:
-			/* sources are disabled from either sysFS or Perf */
+			/*
+			 * We skip the first node in the path assuming that it
+			 * is the source. So we don't expect a source device in
+			 * the middle of a path.
+			 */
+			WARN_ON(1);
 			break;
 		case CORESIGHT_DEV_TYPE_LINK:
 			parent = list_prev_entry(nd, link)->csdev;
@@ -316,6 +331,11 @@ void coresight_disable_path(struct list_head *path)
 	}
 }
 
+void coresight_disable_path(struct list_head *path)
+{
+	coresight_disable_path_from(path, NULL);
+}
+
 int coresight_enable_path(struct list_head *path, u32 mode, void *sink_data)
 {
 
@@ -369,7 +389,7 @@ int coresight_enable_path(struct list_head *path, u32 mode, void *sink_data)
 out:
 	return ret;
 err:
-	coresight_disable_path(path);
+	coresight_disable_path_from(path, nd);
 	goto out;
 }
 
-- 
2.7.4

[PATCH 29/44] coresight: tmc-etr: Refactor for handling errors

[Mathieu Poirier]

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

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>
---
 drivers/hwtracing/coresight/coresight-tmc-etr.c | 67 ++++++++++++++++---------
 1 file changed, 43 insertions(+), 24 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
index 56fea4ff947e..c42693542ec8 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
@@ -918,21 +918,10 @@ static void tmc_sync_etr_buf(struct tmc_drvdata *drvdata)
 		tmc_etr_buf_insert_barrier_packet(etr_buf, etr_buf->offset);
 }
 
-static void tmc_etr_enable_hw(struct tmc_drvdata *drvdata,
-			      struct etr_buf *etr_buf)
+static void __tmc_etr_enable_hw(struct tmc_drvdata *drvdata)
 {
 	u32 axictl, sts;
-
-	/* Callers should provide an appropriate buffer for use */
-	if (WARN_ON(!etr_buf || drvdata->etr_buf))
-		return;
-	drvdata->etr_buf = etr_buf;
-
-	/*
-	 * If this ETR is connected to a CATU, enable it before we turn
-	 * this on
-	 */
-	tmc_etr_enable_catu(drvdata);
+	struct etr_buf *etr_buf = drvdata->etr_buf;
 
 	CS_UNLOCK(drvdata->base);
 
@@ -952,11 +941,8 @@ static void tmc_etr_enable_hw(struct tmc_drvdata *drvdata,
 		axictl |= TMC_AXICTL_ARCACHE_OS;
 	}
 
-	if (etr_buf->mode == ETR_MODE_ETR_SG) {
-		if (WARN_ON(!tmc_etr_has_cap(drvdata, TMC_ETR_SG)))
-			return;
+	if (etr_buf->mode == ETR_MODE_ETR_SG)
 		axictl |= TMC_AXICTL_SCT_GAT_MODE;
-	}
 
 	writel_relaxed(axictl, drvdata->base + TMC_AXICTL);
 	tmc_write_dba(drvdata, etr_buf->hwaddr);
@@ -982,6 +968,32 @@ static void tmc_etr_enable_hw(struct tmc_drvdata *drvdata,
 	CS_LOCK(drvdata->base);
 }
 
+static int tmc_etr_enable_hw(struct tmc_drvdata *drvdata,
+			     struct etr_buf *etr_buf)
+{
+	/* Callers should provide an appropriate buffer for use */
+	if (WARN_ON(!etr_buf))
+		return -EINVAL;
+
+	if ((etr_buf->mode == ETR_MODE_ETR_SG) &&
+	    WARN_ON(!tmc_etr_has_cap(drvdata, TMC_ETR_SG)))
+		return -EINVAL;
+
+	if (WARN_ON(drvdata->etr_buf))
+		return -EBUSY;
+
+	/* Set the buffer for the session */
+	drvdata->etr_buf = etr_buf;
+	/*
+	 * If this ETR is connected to a CATU, enable it before we turn
+	 * this on.
+	 */
+	tmc_etr_enable_catu(drvdata);
+
+	__tmc_etr_enable_hw(drvdata);
+	return 0;
+}
+
 /*
  * Return the available trace data in the buffer (starts at etr_buf->offset,
  * limited by etr_buf->len) from @pos, with a maximum limit of @len,
@@ -1037,7 +1049,7 @@ static void tmc_etr_sync_sysfs_buf(struct tmc_drvdata *drvdata)
 	}
 }
 
-static void tmc_etr_disable_hw(struct tmc_drvdata *drvdata)
+static void __tmc_etr_disable_hw(struct tmc_drvdata *drvdata)
 {
 	CS_UNLOCK(drvdata->base);
 
@@ -1053,6 +1065,11 @@ static void tmc_etr_disable_hw(struct tmc_drvdata *drvdata)
 
 	CS_LOCK(drvdata->base);
 
+}
+
+static void tmc_etr_disable_hw(struct tmc_drvdata *drvdata)
+{
+	__tmc_etr_disable_hw(drvdata);
 	/* Disable CATU device if this ETR is connected to one */
 	tmc_etr_disable_catu(drvdata);
 	/* Reset the ETR buf used by hardware */
@@ -1111,8 +1128,9 @@ static int tmc_enable_etr_sink_sysfs(struct coresight_device *csdev)
 		drvdata->sysfs_buf = new_buf;
 	}
 
-	drvdata->mode = CS_MODE_SYSFS;
-	tmc_etr_enable_hw(drvdata, drvdata->sysfs_buf);
+	ret = tmc_etr_enable_hw(drvdata, drvdata->sysfs_buf);
+	if (!ret)
+		drvdata->mode = CS_MODE_SYSFS;
 out:
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
 
@@ -1342,8 +1360,9 @@ static int tmc_enable_etr_sink_perf(struct coresight_device *csdev, void *data)
 
 	etr_perf->head = PERF_IDX2OFF(handle->head, etr_perf);
 	drvdata->perf_data = etr_perf;
-	drvdata->mode = CS_MODE_PERF;
-	tmc_etr_enable_hw(drvdata, etr_perf->etr_buf);
+	rc = tmc_etr_enable_hw(drvdata, etr_perf->etr_buf);
+	if (!rc)
+		drvdata->mode = CS_MODE_PERF;
 
 unlock_out:
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
@@ -1425,7 +1444,7 @@ int tmc_read_prepare_etr(struct tmc_drvdata *drvdata)
 
 	/* Disable the TMC if we are trying to read from a running session. */
 	if (drvdata->mode == CS_MODE_SYSFS)
-		tmc_etr_disable_hw(drvdata);
+		__tmc_etr_disable_hw(drvdata);
 
 	drvdata->reading = true;
 out:
@@ -1452,7 +1471,7 @@ int tmc_read_unprepare_etr(struct tmc_drvdata *drvdata)
 		 * buffer. Since the tracer is still enabled drvdata::buf can't
 		 * be NULL.
 		 */
-		tmc_etr_enable_hw(drvdata, drvdata->sysfs_buf);
+		__tmc_etr_enable_hw(drvdata);
 	} else {
 		/*
 		 * The ETR is not tracing and the buffer was just read.
-- 
2.7.4

[PATCH 30/44] coresight: tmc-etr: Handle errors enabling CATU

[Mathieu Poirier]

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

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>
---
 drivers/hwtracing/coresight/coresight-tmc-etr.c | 19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
index c42693542ec8..daad52146140 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
@@ -751,12 +751,14 @@ tmc_etr_get_catu_device(struct tmc_drvdata *drvdata)
 	return NULL;
 }
 
-static inline void tmc_etr_enable_catu(struct tmc_drvdata *drvdata)
+static inline int tmc_etr_enable_catu(struct tmc_drvdata *drvdata,
+				      struct etr_buf *etr_buf)
 {
 	struct coresight_device *catu = tmc_etr_get_catu_device(drvdata);
 
 	if (catu && helper_ops(catu)->enable)
-		helper_ops(catu)->enable(catu, drvdata->etr_buf);
+		return helper_ops(catu)->enable(catu, etr_buf);
+	return 0;
 }
 
 static inline void tmc_etr_disable_catu(struct tmc_drvdata *drvdata)
@@ -971,6 +973,8 @@ static void __tmc_etr_enable_hw(struct tmc_drvdata *drvdata)
 static int tmc_etr_enable_hw(struct tmc_drvdata *drvdata,
 			     struct etr_buf *etr_buf)
 {
+	int rc;
+
 	/* Callers should provide an appropriate buffer for use */
 	if (WARN_ON(!etr_buf))
 		return -EINVAL;
@@ -982,16 +986,17 @@ static int tmc_etr_enable_hw(struct tmc_drvdata *drvdata,
 	if (WARN_ON(drvdata->etr_buf))
 		return -EBUSY;
 
-	/* Set the buffer for the session */
-	drvdata->etr_buf = etr_buf;
 	/*
 	 * If this ETR is connected to a CATU, enable it before we turn
 	 * this on.
 	 */
-	tmc_etr_enable_catu(drvdata);
+	rc = tmc_etr_enable_catu(drvdata, etr_buf);
+	if (!rc) {
+		drvdata->etr_buf = etr_buf;
+		__tmc_etr_enable_hw(drvdata);
+	}
 
-	__tmc_etr_enable_hw(drvdata);
-	return 0;
+	return rc;
 }
 
 /*
-- 
2.7.4

[PATCH 31/44] coresight: tmc-etb/etf: Prepare to handle errors enabling

[Mathieu Poirier]

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

Prepare to handle errors in enabling the hardware and
report it back to the core driver.

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 | 73 +++++++++++++++----------
 1 file changed, 45 insertions(+), 28 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-tmc-etf.c b/drivers/hwtracing/coresight/coresight-tmc-etf.c
index b54a3db13fee..36af23d2c0f8 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etf.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etf.c
@@ -15,7 +15,7 @@
 static int tmc_set_etf_buffer(struct coresight_device *csdev,
 			      struct perf_output_handle *handle);
 
-static void tmc_etb_enable_hw(struct tmc_drvdata *drvdata)
+static void __tmc_etb_enable_hw(struct tmc_drvdata *drvdata)
 {
 	CS_UNLOCK(drvdata->base);
 
@@ -34,6 +34,12 @@ static void tmc_etb_enable_hw(struct tmc_drvdata *drvdata)
 	CS_LOCK(drvdata->base);
 }
 
+static int tmc_etb_enable_hw(struct tmc_drvdata *drvdata)
+{
+	__tmc_etb_enable_hw(drvdata);
+	return 0;
+}
+
 static void tmc_etb_dump_hw(struct tmc_drvdata *drvdata)
 {
 	char *bufp;
@@ -73,7 +79,7 @@ static void tmc_etb_disable_hw(struct tmc_drvdata *drvdata)
 	CS_LOCK(drvdata->base);
 }
 
-static void tmc_etf_enable_hw(struct tmc_drvdata *drvdata)
+static void __tmc_etf_enable_hw(struct tmc_drvdata *drvdata)
 {
 	CS_UNLOCK(drvdata->base);
 
@@ -89,6 +95,12 @@ static void tmc_etf_enable_hw(struct tmc_drvdata *drvdata)
 	CS_LOCK(drvdata->base);
 }
 
+static int tmc_etf_enable_hw(struct tmc_drvdata *drvdata)
+{
+	__tmc_etf_enable_hw(drvdata);
+	return 0;
+}
+
 static void tmc_etf_disable_hw(struct tmc_drvdata *drvdata)
 {
 	CS_UNLOCK(drvdata->base);
@@ -171,8 +183,12 @@ static int tmc_enable_etf_sink_sysfs(struct coresight_device *csdev)
 		drvdata->buf = buf;
 	}
 
-	drvdata->mode = CS_MODE_SYSFS;
-	tmc_etb_enable_hw(drvdata);
+	ret = tmc_etb_enable_hw(drvdata);
+	if (!ret)
+		drvdata->mode = CS_MODE_SYSFS;
+	else
+		/* Free up the buffer if we failed to enable */
+		used = false;
 out:
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
 
@@ -191,27 +207,25 @@ static int tmc_enable_etf_sink_perf(struct coresight_device *csdev, void *data)
 	struct perf_output_handle *handle = data;
 
 	spin_lock_irqsave(&drvdata->spinlock, flags);
-	if (drvdata->reading) {
-		ret = -EINVAL;
-		goto out;
-	}
-
-	/*
-	 * 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 (drvdata->mode != CS_MODE_DISABLED) {
+	do {
 		ret = -EINVAL;
-		goto out;
-	}
+		if (drvdata->reading)
+			break;
+		/*
+		 * In Perf mode there can be only one writer per sink.  There
+		 * is also no need to continue if the ETB/ETF is already
+		 * operated from sysFS.
+		 */
+		if (drvdata->mode != CS_MODE_DISABLED)
+			break;
 
-	ret = tmc_set_etf_buffer(csdev, handle);
-	if (!ret) {
-		drvdata->mode = CS_MODE_PERF;
-		tmc_etb_enable_hw(drvdata);
-	}
-out:
+		ret = tmc_set_etf_buffer(csdev, handle);
+		if (ret)
+			break;
+		ret  = tmc_etb_enable_hw(drvdata);
+		if (!ret)
+			drvdata->mode = CS_MODE_PERF;
+	} while (0);
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
 
 	return ret;
@@ -268,6 +282,7 @@ static void tmc_disable_etf_sink(struct coresight_device *csdev)
 static int tmc_enable_etf_link(struct coresight_device *csdev,
 			       int inport, int outport)
 {
+	int ret;
 	unsigned long flags;
 	struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
 
@@ -277,12 +292,14 @@ static int tmc_enable_etf_link(struct coresight_device *csdev,
 		return -EBUSY;
 	}
 
-	tmc_etf_enable_hw(drvdata);
-	drvdata->mode = CS_MODE_SYSFS;
+	ret = tmc_etf_enable_hw(drvdata);
+	if (!ret)
+		drvdata->mode = CS_MODE_SYSFS;
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
 
-	dev_dbg(drvdata->dev, "TMC-ETF enabled\n");
-	return 0;
+	if (!ret)
+		dev_dbg(drvdata->dev, "TMC-ETF enabled\n");
+	return ret;
 }
 
 static void tmc_disable_etf_link(struct coresight_device *csdev,
@@ -576,7 +593,7 @@ int tmc_read_unprepare_etb(struct tmc_drvdata *drvdata)
 		 * can't be NULL.
 		 */
 		memset(drvdata->buf, 0, drvdata->size);
-		tmc_etb_enable_hw(drvdata);
+		__tmc_etb_enable_hw(drvdata);
 	} else {
 		/*
 		 * The ETB/ETF is not tracing and the buffer was just read.
-- 
2.7.4

[PATCH 32/44] coresight: etm4x: Add support for handling errors

[Mathieu Poirier]

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

Add support for handling errors in enabling the component.
The ETM is enabled via cross call to owner CPU. Make
necessary changes to report the error back from the cross
call.

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-etm4x.c | 39 ++++++++++++++++++---------
 1 file changed, 26 insertions(+), 13 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c
index b7379e9cfb30..064e0bfaefd0 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x.c
@@ -78,10 +78,14 @@ static int etm4_trace_id(struct coresight_device *csdev)
 	return drvdata->trcid;
 }
 
-static void etm4_enable_hw(void *info)
+struct etm4_enable_arg {
+	struct etmv4_drvdata *drvdata;
+	int rc;
+};
+
+static int etm4_enable_hw(struct etmv4_drvdata *drvdata)
 {
 	int i;
-	struct etmv4_drvdata *drvdata = info;
 	struct etmv4_config *config = &drvdata->config;
 
 	CS_UNLOCK(drvdata->base);
@@ -178,6 +182,16 @@ static void etm4_enable_hw(void *info)
 	CS_LOCK(drvdata->base);
 
 	dev_dbg(drvdata->dev, "cpu: %d enable smp call done\n", drvdata->cpu);
+	return 0;
+}
+
+static void etm4_enable_hw_smp_call(void *info)
+{
+	struct etm4_enable_arg *arg = info;
+
+	if (WARN_ON(!arg))
+		return;
+	arg->rc = etm4_enable_hw(arg->drvdata);
 }
 
 static int etm4_parse_event_config(struct etmv4_drvdata *drvdata,
@@ -243,7 +257,7 @@ static int etm4_enable_perf(struct coresight_device *csdev,
 	if (ret)
 		goto out;
 	/* And enable it */
-	etm4_enable_hw(drvdata);
+	ret = etm4_enable_hw(drvdata);
 
 out:
 	return ret;
@@ -252,6 +266,7 @@ static int etm4_enable_perf(struct coresight_device *csdev,
 static int etm4_enable_sysfs(struct coresight_device *csdev)
 {
 	struct etmv4_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
+	struct etm4_enable_arg arg = { 0 };
 	int ret;
 
 	spin_lock(&drvdata->spinlock);
@@ -260,19 +275,17 @@ static int etm4_enable_sysfs(struct coresight_device *csdev)
 	 * Executing etm4_enable_hw on the cpu whose ETM is being enabled
 	 * ensures that register writes occur when cpu is powered.
 	 */
+	arg.drvdata = drvdata;
 	ret = smp_call_function_single(drvdata->cpu,
-				       etm4_enable_hw, drvdata, 1);
-	if (ret)
-		goto err;
-
-	drvdata->sticky_enable = true;
+				       etm4_enable_hw_smp_call, &arg, 1);
+	if (!ret)
+		ret = arg.rc;
+	if (!ret)
+		drvdata->sticky_enable = true;
 	spin_unlock(&drvdata->spinlock);
 
-	dev_dbg(drvdata->dev, "ETM tracing enabled\n");
-	return 0;
-
-err:
-	spin_unlock(&drvdata->spinlock);
+	if (!ret)
+		dev_dbg(drvdata->dev, "ETM tracing enabled\n");
 	return ret;
 }
 
-- 
2.7.4

[PATCH 33/44] coresight: etm3: Add support for handling errors

[Mathieu Poirier]

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

Add support for reporting errors back from the SMP cross
function call for enabling ETM.

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-etm3x.c | 42 ++++++++++++++++++---------
 1 file changed, 28 insertions(+), 14 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-etm3x.c b/drivers/hwtracing/coresight/coresight-etm3x.c
index 9ce8fba20b0f..206c2381a11a 100644
--- a/drivers/hwtracing/coresight/coresight-etm3x.c
+++ b/drivers/hwtracing/coresight/coresight-etm3x.c
@@ -355,11 +355,10 @@ static int etm_parse_event_config(struct etm_drvdata *drvdata,
 	return 0;
 }
 
-static void etm_enable_hw(void *info)
+static int etm_enable_hw(struct etm_drvdata *drvdata)
 {
 	int i;
 	u32 etmcr;
-	struct etm_drvdata *drvdata = info;
 	struct etm_config *config = &drvdata->config;
 
 	CS_UNLOCK(drvdata->base);
@@ -421,6 +420,21 @@ static void etm_enable_hw(void *info)
 	CS_LOCK(drvdata->base);
 
 	dev_dbg(drvdata->dev, "cpu: %d enable smp call done\n", drvdata->cpu);
+	return 0;
+}
+
+struct etm_enable_arg {
+	struct etm_drvdata *drvdata;
+	int rc;
+};
+
+static void etm_enable_hw_smp_call(void *info)
+{
+	struct etm_enable_arg *arg = info;
+
+	if (WARN_ON(!arg))
+		return;
+	arg->rc = etm_enable_hw(arg->drvdata);
 }
 
 static int etm_cpu_id(struct coresight_device *csdev)
@@ -475,14 +489,13 @@ static int etm_enable_perf(struct coresight_device *csdev,
 	/* Configure the tracer based on the session's specifics */
 	etm_parse_event_config(drvdata, event);
 	/* And enable it */
-	etm_enable_hw(drvdata);
-
-	return 0;
+	return etm_enable_hw(drvdata);
 }
 
 static int etm_enable_sysfs(struct coresight_device *csdev)
 {
 	struct etm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
+	struct etm_enable_arg arg = { 0 };
 	int ret;
 
 	spin_lock(&drvdata->spinlock);
@@ -492,20 +505,21 @@ static int etm_enable_sysfs(struct coresight_device *csdev)
 	 * hw configuration will take place on the local CPU during bring up.
 	 */
 	if (cpu_online(drvdata->cpu)) {
+		arg.drvdata = drvdata;
 		ret = smp_call_function_single(drvdata->cpu,
-					       etm_enable_hw, drvdata, 1);
-		if (ret)
-			goto err;
+					       etm_enable_hw_smp_call, &arg, 1);
+		if (!ret)
+			ret = arg.rc;
+		if (!ret)
+			drvdata->sticky_enable = true;
+	} else {
+		ret = -ENODEV;
 	}
 
-	drvdata->sticky_enable = true;
 	spin_unlock(&drvdata->spinlock);
 
-	dev_dbg(drvdata->dev, "ETM tracing enabled\n");
-	return 0;
-
-err:
-	spin_unlock(&drvdata->spinlock);
+	if (!ret)
+		dev_dbg(drvdata->dev, "ETM tracing enabled\n");
 	return ret;
 }
 
-- 
2.7.4

[PATCH 34/44] coresight: etb10: Handle errors enabling the device

[Mathieu Poirier]

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

Prepare the etb10 driver to return errors in enabling
the device.

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-etb10.c | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-etb10.c b/drivers/hwtracing/coresight/coresight-etb10.c
index 08fa660098f8..824be0c5f592 100644
--- a/drivers/hwtracing/coresight/coresight-etb10.c
+++ b/drivers/hwtracing/coresight/coresight-etb10.c
@@ -106,7 +106,7 @@ static unsigned int etb_get_buffer_depth(struct etb_drvdata *drvdata)
 	return depth;
 }
 
-static void etb_enable_hw(struct etb_drvdata *drvdata)
+static void __etb_enable_hw(struct etb_drvdata *drvdata)
 {
 	int i;
 	u32 depth;
@@ -134,6 +134,12 @@ static void etb_enable_hw(struct etb_drvdata *drvdata)
 	CS_LOCK(drvdata->base);
 }
 
+static int etb_enable_hw(struct etb_drvdata *drvdata)
+{
+	__etb_enable_hw(drvdata);
+	return 0;
+}
+
 static int etb_enable_sysfs(struct coresight_device *csdev)
 {
 	int ret = 0;
@@ -152,8 +158,9 @@ static int etb_enable_sysfs(struct coresight_device *csdev)
 	if (drvdata->mode == CS_MODE_SYSFS)
 		goto out;
 
-	drvdata->mode = CS_MODE_SYSFS;
-	etb_enable_hw(drvdata);
+	ret = etb_enable_hw(drvdata);
+	if (!ret)
+		drvdata->mode = CS_MODE_SYSFS;
 
 out:
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
@@ -183,8 +190,9 @@ static int etb_enable_perf(struct coresight_device *csdev, void *data)
 	if (ret)
 		goto out;
 
-	drvdata->mode = CS_MODE_PERF;
-	etb_enable_hw(drvdata);
+	ret = etb_enable_hw(drvdata);
+	if (!ret)
+		drvdata->mode = CS_MODE_PERF;
 
 out:
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
-- 
2.7.4

[PATCH 35/44] coresight: dynamic-replicator: Handle multiple connections

[Mathieu Poirier]

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

When a replicator port is enabled, we block the traffic
on the other port and route all traffic to the new enabled
port. If there are two active trace sessions each targeting
the two different paths from the replicator, the second session
will disable the first session and route all the data to the
second path.
                    ETR
                 /
e.g, replicator
                 \
                    ETB

If CPU0 is operated in sysfs mode to ETR and CPU1 is operated
in perf mode to ETB, depending on the order in which the
replicator is enabled one device is blocked.

Ideally we need trace-id for the session to make the
right choice. That implies we need a trace-id allocation
logic for the coresight subsystem and use that to route
the traffic. The short term solution is to only manage
the "target port" and leave the other port untouched.
That leaves both the paths unaffected, except that some
unwanted traffic may be pushed to the paths (if the Trace-IDs
are not far enough), which is still fine and can be filtered
out while processing rather than silently blocking the data.

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>
---
 .../coresight/coresight-dynamic-replicator.c       | 64 ++++++++++++++++------
 1 file changed, 47 insertions(+), 17 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-dynamic-replicator.c b/drivers/hwtracing/coresight/coresight-dynamic-replicator.c
index ebb80438f6a5..97f4673452cb 100644
--- a/drivers/hwtracing/coresight/coresight-dynamic-replicator.c
+++ b/drivers/hwtracing/coresight/coresight-dynamic-replicator.c
@@ -34,26 +34,42 @@ struct replicator_state {
 	struct coresight_device	*csdev;
 };
 
+/*
+ * replicator_reset : Reset the replicator configuration to sane values.
+ */
+static void replicator_reset(struct replicator_state *drvdata)
+{
+	CS_UNLOCK(drvdata->base);
+
+	writel_relaxed(0xff, drvdata->base + REPLICATOR_IDFILTER0);
+	writel_relaxed(0xff, drvdata->base + REPLICATOR_IDFILTER1);
+
+	CS_LOCK(drvdata->base);
+}
+
 static int replicator_enable(struct coresight_device *csdev, int inport,
 			      int outport)
 {
+	u32 reg;
 	struct replicator_state *drvdata = dev_get_drvdata(csdev->dev.parent);
 
+	switch (outport) {
+	case 0:
+		reg = REPLICATOR_IDFILTER0;
+		break;
+	case 1:
+		reg = REPLICATOR_IDFILTER1;
+		break;
+	default:
+		WARN_ON(1);
+		return -EINVAL;
+	}
+
 	CS_UNLOCK(drvdata->base);
 
-	/*
-	 * Ensure that the other port is disabled
-	 * 0x00 - passing through the replicator unimpeded
-	 * 0xff - disable (or impede) the flow of ATB data
-	 */
-	if (outport == 0) {
-		writel_relaxed(0x00, drvdata->base + REPLICATOR_IDFILTER0);
-		writel_relaxed(0xff, drvdata->base + REPLICATOR_IDFILTER1);
-	} else {
-		writel_relaxed(0x00, drvdata->base + REPLICATOR_IDFILTER1);
-		writel_relaxed(0xff, drvdata->base + REPLICATOR_IDFILTER0);
-	}
 
+	/* Ensure that the outport is enabled. */
+	writel_relaxed(0x00, drvdata->base + reg);
 	CS_LOCK(drvdata->base);
 
 	dev_dbg(drvdata->dev, "REPLICATOR enabled\n");
@@ -63,15 +79,25 @@ static int replicator_enable(struct coresight_device *csdev, int inport,
 static void replicator_disable(struct coresight_device *csdev, int inport,
 				int outport)
 {
+	u32 reg;
 	struct replicator_state *drvdata = dev_get_drvdata(csdev->dev.parent);
 
+	switch (outport) {
+	case 0:
+		reg = REPLICATOR_IDFILTER0;
+		break;
+	case 1:
+		reg = REPLICATOR_IDFILTER1;
+		break;
+	default:
+		WARN_ON(1);
+		return;
+	}
+
 	CS_UNLOCK(drvdata->base);
 
 	/* disable the flow of ATB data through port */
-	if (outport == 0)
-		writel_relaxed(0xff, drvdata->base + REPLICATOR_IDFILTER0);
-	else
-		writel_relaxed(0xff, drvdata->base + REPLICATOR_IDFILTER1);
+	writel_relaxed(0xff, drvdata->base + reg);
 
 	CS_LOCK(drvdata->base);
 
@@ -156,7 +182,11 @@ static int replicator_probe(struct amba_device *adev, const struct amba_id *id)
 	desc.groups = replicator_groups;
 	drvdata->csdev = coresight_register(&desc);
 
-	return PTR_ERR_OR_ZERO(drvdata->csdev);
+	if (!IS_ERR(drvdata->csdev)) {
+		replicator_reset(drvdata);
+		return 0;
+	}
+	return PTR_ERR(drvdata->csdev);
 }
 
 #ifdef CONFIG_PM
-- 
2.7.4

[PATCH 36/44] coresight: Add support for CLAIM tag protocol

[Mathieu Poirier]

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

Coresight architecture defines CLAIM tags for a device to negotiate
control of the components (external agent vs self-hosted). Each device
has a pair of registers (CLAIMSET & CLAIMCLR) for managing the CLAIM
tags. However, the protocol for the CLAIM tags is IMPLEMENTATION DEFINED.
PSCI has recommendations for the use of the CLAIM tags to negotiate
controls for external agent vs self-hosted use. This patch implements
the recommended protocol by PSCI.

The claim/disclaim operations are performed from the device specific
drivers. The disadvantage is that the calls are sprinkled in each driver,
but this makes the operation much simpler.

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-priv.h |  7 +++
 drivers/hwtracing/coresight/coresight.c      | 86 ++++++++++++++++++++++++++++
 include/linux/coresight.h                    | 20 +++++++
 3 files changed, 113 insertions(+)

diff --git a/drivers/hwtracing/coresight/coresight-priv.h b/drivers/hwtracing/coresight/coresight-priv.h
index c11da5564a67..579f34943bf1 100644
--- a/drivers/hwtracing/coresight/coresight-priv.h
+++ b/drivers/hwtracing/coresight/coresight-priv.h
@@ -25,6 +25,13 @@
 #define CORESIGHT_DEVID		0xfc8
 #define CORESIGHT_DEVTYPE	0xfcc
 
+
+/*
+ * Coresight device CLAIM protocol.
+ * See PSCI - ARM DEN 0022D, Section: 6.8.1 Debug and Trace save and restore.
+ */
+#define CORESIGHT_CLAIM_SELF_HOSTED	BIT(1)
+
 #define TIMEOUT_US		100
 #define BMVAL(val, lsb, msb)	((val & GENMASK(msb, lsb)) >> lsb)
 
diff --git a/drivers/hwtracing/coresight/coresight.c b/drivers/hwtracing/coresight/coresight.c
index f4f50753cf75..2b0df1a0a8df 100644
--- a/drivers/hwtracing/coresight/coresight.c
+++ b/drivers/hwtracing/coresight/coresight.c
@@ -128,6 +128,92 @@ static int coresight_find_link_outport(struct coresight_device *csdev,
 	return -ENODEV;
 }
 
+static inline u32 coresight_read_claim_tags(void __iomem *base)
+{
+	return readl_relaxed(base + CORESIGHT_CLAIMCLR);
+}
+
+static inline bool coresight_is_claimed_self_hosted(void __iomem *base)
+{
+	return coresight_read_claim_tags(base) == CORESIGHT_CLAIM_SELF_HOSTED;
+}
+
+static inline bool coresight_is_claimed_any(void __iomem *base)
+{
+	return coresight_read_claim_tags(base) != 0;
+}
+
+static inline void coresight_set_claim_tags(void __iomem *base)
+{
+	writel_relaxed(CORESIGHT_CLAIM_SELF_HOSTED, base + CORESIGHT_CLAIMSET);
+	isb();
+}
+
+static inline void coresight_clear_claim_tags(void __iomem *base)
+{
+	writel_relaxed(CORESIGHT_CLAIM_SELF_HOSTED, base + CORESIGHT_CLAIMCLR);
+	isb();
+}
+
+/*
+ * coresight_claim_device_unlocked : Claim the device for self-hosted usage
+ * to prevent an external tool from touching this device. As per PSCI
+ * standards, section "Preserving the execution context" => "Debug and Trace
+ * save and Restore", DBGCLAIM[1] is reserved for Self-hosted debug/trace and
+ * DBGCLAIM[0] is reserved for external tools.
+ *
+ * Called with CS_UNLOCKed for the component.
+ * Returns : 0 on success
+ */
+int coresight_claim_device_unlocked(void __iomem *base)
+{
+	if (coresight_is_claimed_any(base))
+		return -EBUSY;
+
+	coresight_set_claim_tags(base);
+	if (coresight_is_claimed_self_hosted(base))
+		return 0;
+	/* There was a race setting the tags, clean up and fail */
+	coresight_clear_claim_tags(base);
+	return -EBUSY;
+}
+
+int coresight_claim_device(void __iomem *base)
+{
+	int rc;
+
+	CS_UNLOCK(base);
+	rc = coresight_claim_device_unlocked(base);
+	CS_LOCK(base);
+
+	return rc;
+}
+
+/*
+ * coresight_disclaim_device_unlocked : Clear the claim tags for the device.
+ * Called with CS_UNLOCKed for the component.
+ */
+void coresight_disclaim_device_unlocked(void __iomem *base)
+{
+
+	if (coresight_is_claimed_self_hosted(base))
+		coresight_clear_claim_tags(base);
+	else
+		/*
+		 * The external agent may have not honoured our claim
+		 * and has manipulated it. Or something else has seriously
+		 * gone wrong in our driver.
+		 */
+		WARN_ON_ONCE(1);
+}
+
+void coresight_disclaim_device(void __iomem *base)
+{
+	CS_UNLOCK(base);
+	coresight_disclaim_device_unlocked(base);
+	CS_LOCK(base);
+}
+
 static int coresight_enable_sink(struct coresight_device *csdev,
 				 u32 mode, void *data)
 {
diff --git a/include/linux/coresight.h b/include/linux/coresight.h
index 53535821dc25..46c67a764877 100644
--- a/include/linux/coresight.h
+++ b/include/linux/coresight.h
@@ -257,6 +257,13 @@ extern int coresight_enable(struct coresight_device *csdev);
 extern void coresight_disable(struct coresight_device *csdev);
 extern int coresight_timeout(void __iomem *addr, u32 offset,
 			     int position, int value);
+
+extern int coresight_claim_device(void __iomem *base);
+extern int coresight_claim_device_unlocked(void __iomem *base);
+
+extern void coresight_disclaim_device(void __iomem *base);
+extern void coresight_disclaim_device_unlocked(void __iomem *base);
+
 #else
 static inline struct coresight_device *
 coresight_register(struct coresight_desc *desc) { return NULL; }
@@ -266,6 +273,19 @@ coresight_enable(struct coresight_device *csdev) { return -ENOSYS; }
 static inline void coresight_disable(struct coresight_device *csdev) {}
 static inline int coresight_timeout(void __iomem *addr, u32 offset,
 				     int position, int value) { return 1; }
+static inline int coresight_claim_device_unlocked(void __iomem *base)
+{
+	return -EINVAL;
+}
+
+static inline int coresight_claim_device(void __iomem *base)
+{
+	return -EINVAL;
+}
+
+static inline void coresight_disclaim_device(void __iomem *base) {}
+static inline void coresight_disclaim_device_unlocked(void __iomem *base) {}
+
 #endif
 
 #ifdef CONFIG_OF
-- 
2.7.4

[PATCH 37/44] coresight: etmx: Claim devices before use

[Mathieu Poirier]

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

Use the CLAIM tags to grab the device for self-hosted usage.

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-etm3x.c | 16 +++++++++++++---
 drivers/hwtracing/coresight/coresight-etm4x.c | 14 +++++++++++---
 2 files changed, 24 insertions(+), 6 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-etm3x.c b/drivers/hwtracing/coresight/coresight-etm3x.c
index 206c2381a11a..fd5c4cca7db5 100644
--- a/drivers/hwtracing/coresight/coresight-etm3x.c
+++ b/drivers/hwtracing/coresight/coresight-etm3x.c
@@ -357,7 +357,7 @@ static int etm_parse_event_config(struct etm_drvdata *drvdata,
 
 static int etm_enable_hw(struct etm_drvdata *drvdata)
 {
-	int i;
+	int i, rc;
 	u32 etmcr;
 	struct etm_config *config = &drvdata->config;
 
@@ -369,6 +369,9 @@ static int etm_enable_hw(struct etm_drvdata *drvdata)
 	etm_set_pwrup(drvdata);
 	/* Make sure all registers are accessible */
 	etm_os_unlock(drvdata);
+	rc = coresight_claim_device_unlocked(drvdata->base);
+	if (rc)
+		goto done;
 
 	etm_set_prog(drvdata);
 
@@ -417,10 +420,15 @@ static int etm_enable_hw(struct etm_drvdata *drvdata)
 	etm_writel(drvdata, 0x0, ETMVMIDCVR);
 
 	etm_clr_prog(drvdata);
+
+done:
+	if (rc)
+		etm_set_pwrdwn(drvdata);
 	CS_LOCK(drvdata->base);
 
-	dev_dbg(drvdata->dev, "cpu: %d enable smp call done\n", drvdata->cpu);
-	return 0;
+	dev_dbg(drvdata->dev, "cpu: %d enable smp call done: %d\n",
+		drvdata->cpu, rc);
+	return rc;
 }
 
 struct etm_enable_arg {
@@ -569,6 +577,8 @@ static void etm_disable_hw(void *info)
 	for (i = 0; i < drvdata->nr_cntr; i++)
 		config->cntr_val[i] = etm_readl(drvdata, ETMCNTVRn(i));
 
+	coresight_disclaim_device_unlocked(drvdata->base);
+
 	etm_set_pwrdwn(drvdata);
 	CS_LOCK(drvdata->base);
 
diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c
index 064e0bfaefd0..53e2fb6e86f6 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x.c
@@ -85,13 +85,17 @@ struct etm4_enable_arg {
 
 static int etm4_enable_hw(struct etmv4_drvdata *drvdata)
 {
-	int i;
+	int i, rc;
 	struct etmv4_config *config = &drvdata->config;
 
 	CS_UNLOCK(drvdata->base);
 
 	etm4_os_unlock(drvdata);
 
+	rc = coresight_claim_device_unlocked(drvdata->base);
+	if (rc)
+		goto done;
+
 	/* Disable the trace unit before programming trace registers */
 	writel_relaxed(0, drvdata->base + TRCPRGCTLR);
 
@@ -179,10 +183,12 @@ static int etm4_enable_hw(struct etmv4_drvdata *drvdata)
 		dev_err(drvdata->dev,
 			"timeout while waiting for Idle Trace Status\n");
 
+done:
 	CS_LOCK(drvdata->base);
 
-	dev_dbg(drvdata->dev, "cpu: %d enable smp call done\n", drvdata->cpu);
-	return 0;
+	dev_dbg(drvdata->dev, "cpu: %d enable smp call done: %d\n",
+		drvdata->cpu, rc);
+	return rc;
 }
 
 static void etm4_enable_hw_smp_call(void *info)
@@ -342,6 +348,8 @@ static void etm4_disable_hw(void *info)
 	isb();
 	writel_relaxed(control, drvdata->base + TRCPRGCTLR);
 
+	coresight_disclaim_device_unlocked(drvdata->base);
+
 	CS_LOCK(drvdata->base);
 
 	dev_dbg(drvdata->dev, "cpu: %d disable smp call done\n", drvdata->cpu);
-- 
2.7.4

[PATCH 38/44] coresight: funnel: Claim devices before use

[Mathieu Poirier]

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

Use the CLAIM protocol to grab the ownership of the component.

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-funnel.c | 26 +++++++++++++++++++++-----
 1 file changed, 21 insertions(+), 5 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-funnel.c b/drivers/hwtracing/coresight/coresight-funnel.c
index ee7a30bf9480..927925151509 100644
--- a/drivers/hwtracing/coresight/coresight-funnel.c
+++ b/drivers/hwtracing/coresight/coresight-funnel.c
@@ -25,6 +25,7 @@
 #define FUNNEL_HOLDTIME_MASK	0xf00
 #define FUNNEL_HOLDTIME_SHFT	0x8
 #define FUNNEL_HOLDTIME		(0x7 << FUNNEL_HOLDTIME_SHFT)
+#define FUNNEL_ENSx_MASK	0xff
 
 /**
  * struct funnel_drvdata - specifics associated to a funnel component
@@ -42,31 +43,42 @@ struct funnel_drvdata {
 	unsigned long		priority;
 };
 
-static void funnel_enable_hw(struct funnel_drvdata *drvdata, int port)
+static int funnel_enable_hw(struct funnel_drvdata *drvdata, int port)
 {
 	u32 functl;
+	int rc = 0;
 
 	CS_UNLOCK(drvdata->base);
 
 	functl = readl_relaxed(drvdata->base + FUNNEL_FUNCTL);
+	/* Claim the device only when we enable the first slave */
+	if (!(functl & FUNNEL_ENSx_MASK)) {
+		rc = coresight_claim_device_unlocked(drvdata->base);
+		if (rc)
+			goto done;
+	}
+
 	functl &= ~FUNNEL_HOLDTIME_MASK;
 	functl |= FUNNEL_HOLDTIME;
 	functl |= (1 << port);
 	writel_relaxed(functl, drvdata->base + FUNNEL_FUNCTL);
 	writel_relaxed(drvdata->priority, drvdata->base + FUNNEL_PRICTL);
-
+done:
 	CS_LOCK(drvdata->base);
+	return rc;
 }
 
 static int funnel_enable(struct coresight_device *csdev, int inport,
 			 int outport)
 {
+	int rc;
 	struct funnel_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
 
-	funnel_enable_hw(drvdata, inport);
+	rc = funnel_enable_hw(drvdata, inport);
 
-	dev_dbg(drvdata->dev, "FUNNEL inport %d enabled\n", inport);
-	return 0;
+	if (!rc)
+		dev_dbg(drvdata->dev, "FUNNEL inport %d enabled\n", inport);
+	return rc;
 }
 
 static void funnel_disable_hw(struct funnel_drvdata *drvdata, int inport)
@@ -79,6 +91,10 @@ static void funnel_disable_hw(struct funnel_drvdata *drvdata, int inport)
 	functl &= ~(1 << inport);
 	writel_relaxed(functl, drvdata->base + FUNNEL_FUNCTL);
 
+	/* Disclaim the device if none of the slaves are now active */
+	if (!(functl & FUNNEL_ENSx_MASK))
+		coresight_disclaim_device_unlocked(drvdata->base);
+
 	CS_LOCK(drvdata->base);
 }
 
-- 
2.7.4

[PATCH 39/44] coresight: catu: Claim device before use

[Mathieu Poirier]

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

Use the CLAIM protocol to grab the ownership of the component when
in 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>
---
 drivers/hwtracing/coresight/coresight-catu.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/hwtracing/coresight/coresight-catu.c b/drivers/hwtracing/coresight/coresight-catu.c
index ff94e58845b7..170fbb66bda2 100644
--- a/drivers/hwtracing/coresight/coresight-catu.c
+++ b/drivers/hwtracing/coresight/coresight-catu.c
@@ -406,6 +406,7 @@ static inline int catu_wait_for_ready(struct catu_drvdata *drvdata)
 
 static int catu_enable_hw(struct catu_drvdata *drvdata, void *data)
 {
+	int rc;
 	u32 control, mode;
 	struct etr_buf *etr_buf = data;
 
@@ -418,6 +419,10 @@ static int catu_enable_hw(struct catu_drvdata *drvdata, void *data)
 		return -EBUSY;
 	}
 
+	rc = coresight_claim_device_unlocked(drvdata->base);
+	if (rc)
+		return rc;
+
 	control |= BIT(CATU_CONTROL_ENABLE);
 
 	if (etr_buf && etr_buf->mode == ETR_MODE_CATU) {
@@ -459,6 +464,7 @@ static int catu_disable_hw(struct catu_drvdata *drvdata)
 	int rc = 0;
 
 	catu_write_control(drvdata, 0);
+	coresight_disclaim_device_unlocked(drvdata->base);
 	if (catu_wait_for_ready(drvdata)) {
 		dev_info(drvdata->dev, "Timeout while waiting for READY\n");
 		rc = -EAGAIN;
-- 
2.7.4

[PATCH 40/44] coresight: dynamic-replicator: Claim device for use

[Mathieu Poirier]

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

Use CLAIM protocol 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>
---
 .../coresight/coresight-dynamic-replicator.c       | 23 +++++++++++++++++-----
 1 file changed, 18 insertions(+), 5 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-dynamic-replicator.c b/drivers/hwtracing/coresight/coresight-dynamic-replicator.c
index 97f4673452cb..299667b887fc 100644
--- a/drivers/hwtracing/coresight/coresight-dynamic-replicator.c
+++ b/drivers/hwtracing/coresight/coresight-dynamic-replicator.c
@@ -41,8 +41,11 @@ static void replicator_reset(struct replicator_state *drvdata)
 {
 	CS_UNLOCK(drvdata->base);
 
-	writel_relaxed(0xff, drvdata->base + REPLICATOR_IDFILTER0);
-	writel_relaxed(0xff, drvdata->base + REPLICATOR_IDFILTER1);
+	if (!coresight_claim_device_unlocked(drvdata->base)) {
+		writel_relaxed(0xff, drvdata->base + REPLICATOR_IDFILTER0);
+		writel_relaxed(0xff, drvdata->base + REPLICATOR_IDFILTER1);
+		coresight_disclaim_device_unlocked(drvdata->base);
+	}
 
 	CS_LOCK(drvdata->base);
 }
@@ -50,6 +53,7 @@ static void replicator_reset(struct replicator_state *drvdata)
 static int replicator_enable(struct coresight_device *csdev, int inport,
 			      int outport)
 {
+	int rc = 0;
 	u32 reg;
 	struct replicator_state *drvdata = dev_get_drvdata(csdev->dev.parent);
 
@@ -67,13 +71,19 @@ static int replicator_enable(struct coresight_device *csdev, int inport,
 
 	CS_UNLOCK(drvdata->base);
 
+	if ((readl_relaxed(drvdata->base + REPLICATOR_IDFILTER0) == 0xff) &&
+	    (readl_relaxed(drvdata->base + REPLICATOR_IDFILTER1) == 0xff))
+		rc = coresight_claim_device_unlocked(drvdata->base);
 
 	/* Ensure that the outport is enabled. */
-	writel_relaxed(0x00, drvdata->base + reg);
+	if (!rc) {
+		writel_relaxed(0x00, drvdata->base + reg);
+		dev_dbg(drvdata->dev, "REPLICATOR enabled\n");
+	}
+
 	CS_LOCK(drvdata->base);
 
-	dev_dbg(drvdata->dev, "REPLICATOR enabled\n");
-	return 0;
+	return rc;
 }
 
 static void replicator_disable(struct coresight_device *csdev, int inport,
@@ -99,6 +109,9 @@ static void replicator_disable(struct coresight_device *csdev, int inport,
 	/* disable the flow of ATB data through port */
 	writel_relaxed(0xff, drvdata->base + reg);
 
+	if ((readl_relaxed(drvdata->base + REPLICATOR_IDFILTER0) == 0xff) &&
+	    (readl_relaxed(drvdata->base + REPLICATOR_IDFILTER1) == 0xff))
+		coresight_disclaim_device_unlocked(drvdata->base);
 	CS_LOCK(drvdata->base);
 
 	dev_dbg(drvdata->dev, "REPLICATOR disabled\n");
-- 
2.7.4

[PATCH 41/44] coreisght: tmc: Claim device before use

[Mathieu Poirier]

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

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>
---
 drivers/hwtracing/coresight/coresight-tmc-etf.c | 22 +++++++++++++++++++---
 drivers/hwtracing/coresight/coresight-tmc-etr.c |  4 ++++
 2 files changed, 23 insertions(+), 3 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-tmc-etf.c b/drivers/hwtracing/coresight/coresight-tmc-etf.c
index 36af23d2c0f8..53fc83b72a49 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etf.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etf.c
@@ -36,6 +36,11 @@ static void __tmc_etb_enable_hw(struct tmc_drvdata *drvdata)
 
 static int tmc_etb_enable_hw(struct tmc_drvdata *drvdata)
 {
+	int rc = coresight_claim_device(drvdata->base);
+
+	if (rc)
+		return rc;
+
 	__tmc_etb_enable_hw(drvdata);
 	return 0;
 }
@@ -63,7 +68,7 @@ static void tmc_etb_dump_hw(struct tmc_drvdata *drvdata)
 	return;
 }
 
-static void tmc_etb_disable_hw(struct tmc_drvdata *drvdata)
+static void __tmc_etb_disable_hw(struct tmc_drvdata *drvdata)
 {
 	CS_UNLOCK(drvdata->base);
 
@@ -79,6 +84,12 @@ static void tmc_etb_disable_hw(struct tmc_drvdata *drvdata)
 	CS_LOCK(drvdata->base);
 }
 
+static void tmc_etb_disable_hw(struct tmc_drvdata *drvdata)
+{
+	coresight_disclaim_device(drvdata);
+	__tmc_etb_disable_hw(drvdata);
+}
+
 static void __tmc_etf_enable_hw(struct tmc_drvdata *drvdata)
 {
 	CS_UNLOCK(drvdata->base);
@@ -97,6 +108,11 @@ static void __tmc_etf_enable_hw(struct tmc_drvdata *drvdata)
 
 static int tmc_etf_enable_hw(struct tmc_drvdata *drvdata)
 {
+	int rc = coresight_claim_device(drvdata->base);
+
+	if (rc)
+		return rc;
+
 	__tmc_etf_enable_hw(drvdata);
 	return 0;
 }
@@ -107,7 +123,7 @@ static void tmc_etf_disable_hw(struct tmc_drvdata *drvdata)
 
 	tmc_flush_and_stop(drvdata);
 	tmc_disable_hw(drvdata);
-
+	coresight_disclaim_device_unlocked(drvdata->base);
 	CS_LOCK(drvdata->base);
 }
 
@@ -553,7 +569,7 @@ int tmc_read_prepare_etb(struct tmc_drvdata *drvdata)
 
 	/* Disable the TMC if need be */
 	if (drvdata->mode == CS_MODE_SYSFS)
-		tmc_etb_disable_hw(drvdata);
+		__tmc_etb_disable_hw(drvdata);
 
 	drvdata->reading = true;
 out:
diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
index daad52146140..f684283890d3 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
@@ -991,6 +991,9 @@ static int tmc_etr_enable_hw(struct tmc_drvdata *drvdata,
 	 * this on.
 	 */
 	rc = tmc_etr_enable_catu(drvdata, etr_buf);
+	if (rc)
+		return rc;
+	rc = coresight_claim_device(drvdata->base);
 	if (!rc) {
 		drvdata->etr_buf = etr_buf;
 		__tmc_etr_enable_hw(drvdata);
@@ -1077,6 +1080,7 @@ static void tmc_etr_disable_hw(struct tmc_drvdata *drvdata)
 	__tmc_etr_disable_hw(drvdata);
 	/* Disable CATU device if this ETR is connected to one */
 	tmc_etr_disable_catu(drvdata);
+	coresight_disclaim_device(drvdata->base);
 	/* Reset the ETR buf used by hardware */
 	drvdata->etr_buf = NULL;
 }
-- 
2.7.4

[PATCH 42/44] coresight: dts: binding: Fix example for TPIU component

[Mathieu Poirier]

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

TPIU component has an input port. The example uses out-ports
which is wrong. Let us fix it.

Reported-by: Leo Yan <leo.yan@linaro.org>
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>
---
 Documentation/devicetree/bindings/arm/coresight.txt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/arm/coresight.txt b/Documentation/devicetree/bindings/arm/coresight.txt
index f39d2c6eb49c..13b6198ce01c 100644
--- a/Documentation/devicetree/bindings/arm/coresight.txt
+++ b/Documentation/devicetree/bindings/arm/coresight.txt
@@ -132,7 +132,7 @@ Example:
 
 		clocks = <&oscclk6a>;
 		clock-names = "apb_pclk";
-		out-ports {
+		in-ports {
 			port {
 				tpiu_in_port: endpoint@0 {
 					remote-endpoint = <&replicator_out_port1>;
-- 
2.7.4

[PATCH 43/44] coresight: dts: binding: Update coresight binding examples

[Mathieu Poirier]

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

While we updated the coresight DT bindings, some of the
new examples were not updated due to the order in which they
were merged. Let us update all the missed out ones to the
new bindings to avoid confusion.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Rob Herring <robh@kernel.org>
Cc: Frank Rowand <frowand.list@gmail.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
 .../devicetree/bindings/arm/coresight.txt          | 25 +++++++++-------------
 1 file changed, 10 insertions(+), 15 deletions(-)

diff --git a/Documentation/devicetree/bindings/arm/coresight.txt b/Documentation/devicetree/bindings/arm/coresight.txt
index 13b6198ce01c..f8aff65ab921 100644
--- a/Documentation/devicetree/bindings/arm/coresight.txt
+++ b/Documentation/devicetree/bindings/arm/coresight.txt
@@ -147,22 +147,16 @@ Example:
 
 		clocks = <&oscclk6a>;
 		clock-names = "apb_pclk";
-		ports {
-			#address-cells = <1>;
-			#size-cells = <0>;
-
-			/* input port */
-			port@0 {
-				reg =  <0>;
+		in-ports {
+			port {
 				etr_in_port: endpoint {
-					slave-mode;
 					remote-endpoint = <&replicator2_out_port0>;
 				};
 			};
+		};
 
-			/* CATU link represented by output port */
-			port@1 {
-				reg = <1>;
+		out-ports {
+			port {
 				etr_out_port: endpoint {
 					remote-endpoint = <&catu_in_port>;
 				};
@@ -310,10 +304,11 @@ Example:
 		clock-names = "apb_pclk";
 
 		interrupts = <GIC_SPI 4 IRQ_TYPE_LEVEL_HIGH>;
-		port {
-			catu_in_port: endpoint {
-				slave-mode;
-				remote-endpoint = <&etr_out_port>;
+		in-ports {
+			port {
+				catu_in_port: endpoint {
+					remote-endpoint = <&etr_out_port>;
+				};
 			};
 		};
 	};
-- 
2.7.4

[PATCH 44/44] coresight: Remove redundant null pointer check before of_node_put and put_device

[Mathieu Poirier]

From: zhong jiang <zhongjiang@huawei.com>

of_node_put and put_device has taken the null pointer check into account.
So it is safe to remove the duplicated check.

Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
 drivers/hwtracing/coresight/of_coresight.c | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/drivers/hwtracing/coresight/of_coresight.c b/drivers/hwtracing/coresight/of_coresight.c
index da71c975e3f7..89092f83567e 100644
--- a/drivers/hwtracing/coresight/of_coresight.c
+++ b/drivers/hwtracing/coresight/of_coresight.c
@@ -219,12 +219,9 @@ static int of_coresight_parse_endpoint(struct device *dev,
 		ret = 1;
 	} while (0);
 
-	if (rparent)
-		of_node_put(rparent);
-	if (rep)
-		of_node_put(rep);
-	if (rdev)
-		put_device(rdev);
+	of_node_put(rparent);
+	of_node_put(rep);
+	put_device(rdev);
 
 	return ret;
 }
-- 
2.7.4