[PATCH 00/25] coresight: next v4.18-rc4

[PATCH 00/25] coresight: next v4.18-rc4

[Mathieu Poirier]

Hi Greg, 

These are the patches I've rounded up for inclusion in the v4.19 cycle.  Applies
cleanly on your char-mist/next branch.

Thanks,
Mathieu

Arnd Bergmann (1):
  coresight: include vmalloc.h for vmap/vunmap

Mathieu Poirier (3):
  coresight: etm3x: Don't use contextID with PID namespaces
  coresight: etm4x: Don't use contextID with PID namespaces
  coresight: Remove function coresight_vpid_to_pid()

Robin Murphy (1):
  coresight: tpiu: Fix disabling timeouts

Suzuki K Poulose (20):
  coresight: ETM: Add support for Arm Cortex-A73 and Cortex-A35
  coresight: tmc: Hide trace buffer handling for file read
  coresight: tmc-etr: Do not clean trace buffer
  coresight: tmc-etr: Disallow perf mode
  coresight: Add helper for inserting synchronization packets
  dts: bindings: Restrict coresight tmc-etr scatter-gather mode
  coresight: Add generic TMC sg table framework
  coresight: Add support for TMC ETR SG unit
  coresight: tmc-etr: Add transparent buffer management
  coresight: tmc-etr buf: Add TMC scatter gather mode backend
  coresight: tmc: Add configuration support for trace buffer size
  coresight: Fix check in coresight_tmc_etr_buf_insert_barrier_packet
  coresight: Cleanup platform description data
  coresight: Handle errors in finding input/output ports
  coresight: Cleanup device subtype struct
  coresight: Add helper device type
  coresight: Introduce support for Coresight Address Translation Unit
  dts: bindings: Document device tree binding for CATU
  coresight: catu: Add support for scatter gather tables
  coresight: catu: Plug in CATU as a backend for ETR buffer

 .../ABI/testing/sysfs-bus-coresight-devices-tmc    |    8 +
 .../devicetree/bindings/arm/coresight.txt          |   58 +-
 drivers/hwtracing/coresight/Kconfig                |   11 +
 drivers/hwtracing/coresight/Makefile               |    1 +
 drivers/hwtracing/coresight/coresight-catu.c       |  577 +++++++++++
 drivers/hwtracing/coresight/coresight-catu.h       |  119 +++
 drivers/hwtracing/coresight/coresight-etb10.c      |   12 +-
 drivers/hwtracing/coresight/coresight-etm.h        |    3 -
 .../hwtracing/coresight/coresight-etm3x-sysfs.c    |   43 +-
 drivers/hwtracing/coresight/coresight-etm3x.c      |    4 +-
 .../hwtracing/coresight/coresight-etm4x-sysfs.c    |   47 +-
 drivers/hwtracing/coresight/coresight-etm4x.c      |   31 +-
 drivers/hwtracing/coresight/coresight-etm4x.h      |    3 -
 drivers/hwtracing/coresight/coresight-priv.h       |   10 +-
 drivers/hwtracing/coresight/coresight-tmc-etf.c    |   45 +-
 drivers/hwtracing/coresight/coresight-tmc-etr.c    | 1074 ++++++++++++++++++--
 drivers/hwtracing/coresight/coresight-tmc.c        |   83 +-
 drivers/hwtracing/coresight/coresight-tmc.h        |  113 +-
 drivers/hwtracing/coresight/coresight-tpiu.c       |    7 +-
 drivers/hwtracing/coresight/coresight.c            |   53 +-
 include/linux/coresight.h                          |   68 +-
 21 files changed, 2135 insertions(+), 235 deletions(-)
 create mode 100644 drivers/hwtracing/coresight/coresight-catu.c
 create mode 100644 drivers/hwtracing/coresight/coresight-catu.h

-- 
2.7.4

[PATCH 01/25] coresight: etm3x: Don't use contextID with PID namespaces

[Mathieu Poirier]

Tracers can trigger trace acquisition based on contextID value, something
that isn't useful when PID namespaces are enabled.  Indeed the PID value
of a process has a different representation in the kernel and the PID
namespace, making the feature confusing and potentially leaking internal
kernel information.

As such simply return an error when the feature is being used from a
PID namespace other than the default one.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Kim Phillips <kim.phillips@arm.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 drivers/hwtracing/coresight/coresight-etm.h        |  3 --
 .../hwtracing/coresight/coresight-etm3x-sysfs.c    | 43 +++++++++++++++++++---
 drivers/hwtracing/coresight/coresight-etm3x.c      |  4 +-
 3 files changed, 38 insertions(+), 12 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-etm.h b/drivers/hwtracing/coresight/coresight-etm.h
index e8b4549e30e2..79e1ad860d8a 100644
--- a/drivers/hwtracing/coresight/coresight-etm.h
+++ b/drivers/hwtracing/coresight/coresight-etm.h
@@ -168,8 +168,6 @@
  * @seq_curr_state: current value of the sequencer register.
  * @ctxid_idx: index for the context ID registers.
  * @ctxid_pid: value for the context ID to trigger on.
- * @ctxid_vpid:	Virtual PID seen by users if PID namespace is enabled, otherwise
- *		the same value of ctxid_pid.
  * @ctxid_mask: mask applicable to all the context IDs.
  * @sync_freq:	Synchronisation frequency.
  * @timestamp_event: Defines an event that requests the insertion
@@ -202,7 +200,6 @@ struct etm_config {
 	u32				seq_curr_state;
 	u8				ctxid_idx;
 	u32				ctxid_pid[ETM_MAX_CTXID_CMP];
-	u32				ctxid_vpid[ETM_MAX_CTXID_CMP];
 	u32				ctxid_mask;
 	u32				sync_freq;
 	u32				timestamp_event;
diff --git a/drivers/hwtracing/coresight/coresight-etm3x-sysfs.c b/drivers/hwtracing/coresight/coresight-etm3x-sysfs.c
index 9435c1481f61..75487b3fad86 100644
--- a/drivers/hwtracing/coresight/coresight-etm3x-sysfs.c
+++ b/drivers/hwtracing/coresight/coresight-etm3x-sysfs.c
@@ -4,6 +4,7 @@
  * Author: Mathieu Poirier <mathieu.poirier@linaro.org>
  */
 
+#include <linux/pid_namespace.h>
 #include <linux/pm_runtime.h>
 #include <linux/sysfs.h>
 #include "coresight-etm.h"
@@ -1025,8 +1026,15 @@ static ssize_t ctxid_pid_show(struct device *dev,
 	struct etm_drvdata *drvdata = dev_get_drvdata(dev->parent);
 	struct etm_config *config = &drvdata->config;
 
+	/*
+	 * Don't use contextID tracing if coming from a PID namespace.  See
+	 * comment in ctxid_pid_store().
+	 */
+	if (task_active_pid_ns(current) != &init_pid_ns)
+		return -EINVAL;
+
 	spin_lock(&drvdata->spinlock);
-	val = config->ctxid_vpid[config->ctxid_idx];
+	val = config->ctxid_pid[config->ctxid_idx];
 	spin_unlock(&drvdata->spinlock);
 
 	return sprintf(buf, "%#lx\n", val);
@@ -1037,19 +1045,28 @@ static ssize_t ctxid_pid_store(struct device *dev,
 			       const char *buf, size_t size)
 {
 	int ret;
-	unsigned long vpid, pid;
+	unsigned long pid;
 	struct etm_drvdata *drvdata = dev_get_drvdata(dev->parent);
 	struct etm_config *config = &drvdata->config;
 
-	ret = kstrtoul(buf, 16, &vpid);
+	/*
+	 * When contextID tracing is enabled the tracers will insert the
+	 * value found in the contextID register in the trace stream.  But if
+	 * a process is in a namespace the PID of that process as seen from the
+	 * namespace won't be what the kernel sees, something that makes the
+	 * feature confusing and can potentially leak kernel only information.
+	 * As such refuse to use the feature if @current is not in the initial
+	 * PID namespace.
+	 */
+	if (task_active_pid_ns(current) != &init_pid_ns)
+		return -EINVAL;
+
+	ret = kstrtoul(buf, 16, &pid);
 	if (ret)
 		return ret;
 
-	pid = coresight_vpid_to_pid(vpid);
-
 	spin_lock(&drvdata->spinlock);
 	config->ctxid_pid[config->ctxid_idx] = pid;
-	config->ctxid_vpid[config->ctxid_idx] = vpid;
 	spin_unlock(&drvdata->spinlock);
 
 	return size;
@@ -1063,6 +1080,13 @@ static ssize_t ctxid_mask_show(struct device *dev,
 	struct etm_drvdata *drvdata = dev_get_drvdata(dev->parent);
 	struct etm_config *config = &drvdata->config;
 
+	/*
+	 * Don't use contextID tracing if coming from a PID namespace.  See
+	 * comment in ctxid_pid_store().
+	 */
+	if (task_active_pid_ns(current) != &init_pid_ns)
+		return -EINVAL;
+
 	val = config->ctxid_mask;
 	return sprintf(buf, "%#lx\n", val);
 }
@@ -1076,6 +1100,13 @@ static ssize_t ctxid_mask_store(struct device *dev,
 	struct etm_drvdata *drvdata = dev_get_drvdata(dev->parent);
 	struct etm_config *config = &drvdata->config;
 
+	/*
+	 * Don't use contextID tracing if coming from a PID namespace.  See
+	 * comment in ctxid_pid_store().
+	 */
+	if (task_active_pid_ns(current) != &init_pid_ns)
+		return -EINVAL;
+
 	ret = kstrtoul(buf, 16, &val);
 	if (ret)
 		return ret;
diff --git a/drivers/hwtracing/coresight/coresight-etm3x.c b/drivers/hwtracing/coresight/coresight-etm3x.c
index 15ed64d51a5b..7c74263c333d 100644
--- a/drivers/hwtracing/coresight/coresight-etm3x.c
+++ b/drivers/hwtracing/coresight/coresight-etm3x.c
@@ -230,10 +230,8 @@ void etm_set_default(struct etm_config *config)
 
 	config->seq_curr_state = 0x0;
 	config->ctxid_idx = 0x0;
-	for (i = 0; i < ETM_MAX_CTXID_CMP; i++) {
+	for (i = 0; i < ETM_MAX_CTXID_CMP; i++)
 		config->ctxid_pid[i] = 0x0;
-		config->ctxid_vpid[i] = 0x0;
-	}
 
 	config->ctxid_mask = 0x0;
 	/* Setting default to 1024 as per TRM recommendation */
-- 
2.7.4

[PATCH 02/25] coresight: etm4x: Don't use contextID with PID namespaces

[Mathieu Poirier]

As with ETM3x, the ETM4x tracers can trigger trace acquisition based on
contextID value, something that isn't useful when PID namespaces are
enabled.  Indeed the PID value of a process has a different representation
in the kernel and the PID namespace, making the feature confusing and
potentially leaking internal kernel information.

As such simply return an error when the feature is being used from a
PID namespace other than the default one.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Kim Phillips <kim.phillips@arm.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 .../hwtracing/coresight/coresight-etm4x-sysfs.c    | 47 +++++++++++++++++-----
 drivers/hwtracing/coresight/coresight-etm4x.h      |  3 --
 2 files changed, 38 insertions(+), 12 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c b/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c
index 4eb8da785ce0..a0365e23678e 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x-sysfs.c
@@ -4,6 +4,7 @@
  * Author: Mathieu Poirier <mathieu.poirier@linaro.org>
  */
 
+#include <linux/pid_namespace.h>
 #include <linux/pm_runtime.h>
 #include <linux/sysfs.h>
 #include "coresight-etm4x.h"
@@ -250,10 +251,8 @@ static ssize_t reset_store(struct device *dev,
 	}
 
 	config->ctxid_idx = 0x0;
-	for (i = 0; i < drvdata->numcidc; i++) {
+	for (i = 0; i < drvdata->numcidc; i++)
 		config->ctxid_pid[i] = 0x0;
-		config->ctxid_vpid[i] = 0x0;
-	}
 
 	config->ctxid_mask0 = 0x0;
 	config->ctxid_mask1 = 0x0;
@@ -1637,9 +1636,16 @@ static ssize_t ctxid_pid_show(struct device *dev,
 	struct etmv4_drvdata *drvdata = dev_get_drvdata(dev->parent);
 	struct etmv4_config *config = &drvdata->config;
 
+	/*
+	 * Don't use contextID tracing if coming from a PID namespace.  See
+	 * comment in ctxid_pid_store().
+	 */
+	if (task_active_pid_ns(current) != &init_pid_ns)
+		return -EINVAL;
+
 	spin_lock(&drvdata->spinlock);
 	idx = config->ctxid_idx;
-	val = (unsigned long)config->ctxid_vpid[idx];
+	val = (unsigned long)config->ctxid_pid[idx];
 	spin_unlock(&drvdata->spinlock);
 	return scnprintf(buf, PAGE_SIZE, "%#lx\n", val);
 }
@@ -1649,26 +1655,35 @@ static ssize_t ctxid_pid_store(struct device *dev,
 			       const char *buf, size_t size)
 {
 	u8 idx;
-	unsigned long vpid, pid;
+	unsigned long pid;
 	struct etmv4_drvdata *drvdata = dev_get_drvdata(dev->parent);
 	struct etmv4_config *config = &drvdata->config;
 
 	/*
+	 * When contextID tracing is enabled the tracers will insert the
+	 * value found in the contextID register in the trace stream.  But if
+	 * a process is in a namespace the PID of that process as seen from the
+	 * namespace won't be what the kernel sees, something that makes the
+	 * feature confusing and can potentially leak kernel only information.
+	 * As such refuse to use the feature if @current is not in the initial
+	 * PID namespace.
+	 */
+	if (task_active_pid_ns(current) != &init_pid_ns)
+		return -EINVAL;
+
+	/*
 	 * only implemented when ctxid tracing is enabled, i.e. at least one
 	 * ctxid comparator is implemented and ctxid is greater than 0 bits
 	 * in length
 	 */
 	if (!drvdata->ctxid_size || !drvdata->numcidc)
 		return -EINVAL;
-	if (kstrtoul(buf, 16, &vpid))
+	if (kstrtoul(buf, 16, &pid))
 		return -EINVAL;
 
-	pid = coresight_vpid_to_pid(vpid);
-
 	spin_lock(&drvdata->spinlock);
 	idx = config->ctxid_idx;
 	config->ctxid_pid[idx] = (u64)pid;
-	config->ctxid_vpid[idx] = (u64)vpid;
 	spin_unlock(&drvdata->spinlock);
 	return size;
 }
@@ -1682,6 +1697,13 @@ static ssize_t ctxid_masks_show(struct device *dev,
 	struct etmv4_drvdata *drvdata = dev_get_drvdata(dev->parent);
 	struct etmv4_config *config = &drvdata->config;
 
+	/*
+	 * Don't use contextID tracing if coming from a PID namespace.  See
+	 * comment in ctxid_pid_store().
+	 */
+	if (task_active_pid_ns(current) != &init_pid_ns)
+		return -EINVAL;
+
 	spin_lock(&drvdata->spinlock);
 	val1 = config->ctxid_mask0;
 	val2 = config->ctxid_mask1;
@@ -1699,6 +1721,13 @@ static ssize_t ctxid_masks_store(struct device *dev,
 	struct etmv4_config *config = &drvdata->config;
 
 	/*
+	 * Don't use contextID tracing if coming from a PID namespace.  See
+	 * comment in ctxid_pid_store().
+	 */
+	if (task_active_pid_ns(current) != &init_pid_ns)
+		return -EINVAL;
+
+	/*
 	 * only implemented when ctxid tracing is enabled, i.e. at least one
 	 * ctxid comparator is implemented and ctxid is greater than 0 bits
 	 * in length
diff --git a/drivers/hwtracing/coresight/coresight-etm4x.h b/drivers/hwtracing/coresight/coresight-etm4x.h
index b7c4a6f6c6b9..52786e9d8926 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x.h
+++ b/drivers/hwtracing/coresight/coresight-etm4x.h
@@ -230,8 +230,6 @@
  * @addr_type:	Current status of the comparator register.
  * @ctxid_idx:	Context ID index selector.
  * @ctxid_pid:	Value of the context ID comparator.
- * @ctxid_vpid:	Virtual PID seen by users if PID namespace is enabled, otherwise
- *		the same value of ctxid_pid.
  * @ctxid_mask0:Context ID comparator mask for comparator 0-3.
  * @ctxid_mask1:Context ID comparator mask for comparator 4-7.
  * @vmid_idx:	VM ID index selector.
@@ -274,7 +272,6 @@ struct etmv4_config {
 	u8				addr_type[ETM_MAX_SINGLE_ADDR_CMP];
 	u8				ctxid_idx;
 	u64				ctxid_pid[ETMv4_MAX_CTXID_CMP];
-	u64				ctxid_vpid[ETMv4_MAX_CTXID_CMP];
 	u32				ctxid_mask0;
 	u32				ctxid_mask1;
 	u8				vmid_idx;
-- 
2.7.4

[PATCH 03/25] coresight: Remove function coresight_vpid_to_pid()

[Mathieu Poirier]

Now that we prevent users from using contextID tracing when PID namespaces
are involved there is no client for function coresight_vpid_to_pid().  As
such simply remove it.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Kim Phillips <kim.phillips@arm.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
---
 include/linux/coresight.h | 20 --------------------
 1 file changed, 20 deletions(-)

diff --git a/include/linux/coresight.h b/include/linux/coresight.h
index c265e0468414..e5421b83e4e6 100644
--- a/include/linux/coresight.h
+++ b/include/linux/coresight.h
@@ -267,24 +267,4 @@ static inline struct coresight_platform_data *of_get_coresight_platform_data(
 	struct device *dev, const struct device_node *node) { return NULL; }
 #endif
 
-#ifdef CONFIG_PID_NS
-static inline unsigned long
-coresight_vpid_to_pid(unsigned long vpid)
-{
-	struct task_struct *task = NULL;
-	unsigned long pid = 0;
-
-	rcu_read_lock();
-	task = find_task_by_vpid(vpid);
-	if (task)
-		pid = task_pid_nr(task);
-	rcu_read_unlock();
-
-	return pid;
-}
-#else
-static inline unsigned long
-coresight_vpid_to_pid(unsigned long vpid) { return vpid; }
-#endif
-
 #endif
-- 
2.7.4

[PATCH 04/25] coresight: ETM: Add support for Arm Cortex-A73 and Cortex-A35

[Mathieu Poirier]

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

Add ETM PIDs of the Arm cortex-A CPUs to the white list of ETMs.
While at it add a helper macro to make it easier to add the new
entries.

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 | 31 ++++++++++++---------------
 1 file changed, 14 insertions(+), 17 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c
index 9bc04c50d45b..1d94ebec027b 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x.c
@@ -1027,7 +1027,8 @@ static int etm4_probe(struct amba_device *adev, const struct amba_id *id)
 	}
 
 	pm_runtime_put(&adev->dev);
-	dev_info(dev, "%s initialized\n", (char *)id->data);
+	dev_info(dev, "CPU%d: ETM v%d.%d initialized\n",
+		 drvdata->cpu, drvdata->arch >> 4, drvdata->arch & 0xf);
 
 	if (boot_enable) {
 		coresight_enable(drvdata->csdev);
@@ -1045,23 +1046,19 @@ static int etm4_probe(struct amba_device *adev, const struct amba_id *id)
 	return ret;
 }
 
+#define ETM4x_AMBA_ID(pid)			\
+	{					\
+		.id	= pid,			\
+		.mask	= 0x000fffff,		\
+	}
+
 static const struct amba_id etm4_ids[] = {
-	{       /* ETM 4.0 - Cortex-A53  */
-		.id	= 0x000bb95d,
-		.mask	= 0x000fffff,
-		.data	= "ETM 4.0",
-	},
-	{       /* ETM 4.0 - Cortex-A57 */
-		.id	= 0x000bb95e,
-		.mask	= 0x000fffff,
-		.data	= "ETM 4.0",
-	},
-	{       /* ETM 4.0 - A72, Maia, HiSilicon */
-		.id = 0x000bb95a,
-		.mask = 0x000fffff,
-		.data = "ETM 4.0",
-	},
-	{ 0, 0},
+	ETM4x_AMBA_ID(0x000bb95d),		/* Cortex-A53 */
+	ETM4x_AMBA_ID(0x000bb95e),		/* Cortex-A57 */
+	ETM4x_AMBA_ID(0x000bb95a),		/* Cortex-A72 */
+	ETM4x_AMBA_ID(0x000bb959),		/* Cortex-A73 */
+	ETM4x_AMBA_ID(0x000bb9da),		/* Cortex-A35 */
+	{},
 };
 
 static struct amba_driver etm4x_driver = {
-- 
2.7.4

[PATCH 05/25] coresight: tmc: Hide trace buffer handling for file read

[Mathieu Poirier]

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

At the moment we adjust the buffer pointers for reading the trace
data via misc device in the common code for ETF/ETB and ETR. Since
we are going to change how we manage the buffer for ETR, let us
move the buffer manipulation to the respective driver files, hiding
it from the common code. We do so by adding type specific helpers
for finding the length of data and the pointer to the buffer,
for a given length at a file position.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
 drivers/hwtracing/coresight/coresight-tmc-etf.c | 18 +++++++++++
 drivers/hwtracing/coresight/coresight-tmc-etr.c | 34 ++++++++++++++++++++
 drivers/hwtracing/coresight/coresight-tmc.c     | 41 ++++++++++++++-----------
 drivers/hwtracing/coresight/coresight-tmc.h     |  4 +++
 4 files changed, 79 insertions(+), 18 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-tmc-etf.c b/drivers/hwtracing/coresight/coresight-tmc-etf.c
index 61d849b11c26..73160cd0e0d1 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etf.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etf.c
@@ -109,6 +109,24 @@ static void tmc_etf_disable_hw(struct tmc_drvdata *drvdata)
 	CS_LOCK(drvdata->base);
 }
 
+/*
+ * Return the available trace data in the buffer from @pos, with
+ * a maximum limit of @len, updating the @bufpp on where to
+ * find it.
+ */
+ssize_t tmc_etb_get_sysfs_trace(struct tmc_drvdata *drvdata,
+				loff_t pos, size_t len, char **bufpp)
+{
+	ssize_t actual = len;
+
+	/* Adjust the len to available size @pos */
+	if (pos + actual > drvdata->len)
+		actual = drvdata->len - pos;
+	if (actual > 0)
+		*bufpp = drvdata->buf + pos;
+	return actual;
+}
+
 static int tmc_enable_etf_sink_sysfs(struct coresight_device *csdev)
 {
 	int ret = 0;
diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
index 02f747afa2ba..f88342d400ef 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
@@ -58,6 +58,40 @@ static void tmc_etr_enable_hw(struct tmc_drvdata *drvdata)
 	CS_LOCK(drvdata->base);
 }
 
+/*
+ * Return the available trace data in the buffer @pos, with a maximum
+ * limit of @len, also updating the @bufpp on where to find it.
+ */
+ssize_t tmc_etr_get_sysfs_trace(struct tmc_drvdata *drvdata,
+				loff_t pos, size_t len, char **bufpp)
+{
+	ssize_t actual = len;
+	char *bufp = drvdata->buf + pos;
+	char *bufend = (char *)(drvdata->vaddr + drvdata->size);
+
+	/* Adjust the len to available size @pos */
+	if (pos + actual > drvdata->len)
+		actual = drvdata->len - pos;
+
+	if (actual <= 0)
+		return actual;
+
+	/*
+	 * Since we use a circular buffer, with trace data starting
+	 * @drvdata->buf, possibly anywhere in the buffer @drvdata->vaddr,
+	 * wrap the current @pos to within the buffer.
+	 */
+	if (bufp >= bufend)
+		bufp -= drvdata->size;
+	/*
+	 * For simplicity, avoid copying over a wrapped around buffer.
+	 */
+	if ((bufp + actual) > bufend)
+		actual = bufend - bufp;
+	*bufpp = bufp;
+	return actual;
+}
+
 static void tmc_etr_dump_hw(struct tmc_drvdata *drvdata)
 {
 	const u32 *barrier;
diff --git a/drivers/hwtracing/coresight/coresight-tmc.c b/drivers/hwtracing/coresight/coresight-tmc.c
index 456f122df74f..bb57e7f57eb5 100644
--- a/drivers/hwtracing/coresight/coresight-tmc.c
+++ b/drivers/hwtracing/coresight/coresight-tmc.c
@@ -123,35 +123,40 @@ static int tmc_open(struct inode *inode, struct file *file)
 	return 0;
 }
 
+static inline ssize_t tmc_get_sysfs_trace(struct tmc_drvdata *drvdata,
+					  loff_t pos, size_t len, char **bufpp)
+{
+	switch (drvdata->config_type) {
+	case TMC_CONFIG_TYPE_ETB:
+	case TMC_CONFIG_TYPE_ETF:
+		return tmc_etb_get_sysfs_trace(drvdata, pos, len, bufpp);
+	case TMC_CONFIG_TYPE_ETR:
+		return tmc_etr_get_sysfs_trace(drvdata, pos, len, bufpp);
+	}
+
+	return -EINVAL;
+}
+
 static ssize_t tmc_read(struct file *file, char __user *data, size_t len,
 			loff_t *ppos)
 {
+	char *bufp;
+	ssize_t actual;
 	struct tmc_drvdata *drvdata = container_of(file->private_data,
 						   struct tmc_drvdata, miscdev);
-	char *bufp = drvdata->buf + *ppos;
-
-	if (*ppos + len > drvdata->len)
-		len = drvdata->len - *ppos;
-
-	if (drvdata->config_type == TMC_CONFIG_TYPE_ETR) {
-		if (bufp == (char *)(drvdata->vaddr + drvdata->size))
-			bufp = drvdata->vaddr;
-		else if (bufp > (char *)(drvdata->vaddr + drvdata->size))
-			bufp -= drvdata->size;
-		if ((bufp + len) > (char *)(drvdata->vaddr + drvdata->size))
-			len = (char *)(drvdata->vaddr + drvdata->size) - bufp;
-	}
+	actual = tmc_get_sysfs_trace(drvdata, *ppos, len, &bufp);
+	if (actual <= 0)
+		return 0;
 
-	if (copy_to_user(data, bufp, len)) {
+	if (copy_to_user(data, bufp, actual)) {
 		dev_dbg(drvdata->dev, "%s: copy_to_user failed\n", __func__);
 		return -EFAULT;
 	}
 
-	*ppos += len;
+	*ppos += actual;
+	dev_dbg(drvdata->dev, "%zu bytes copied\n", actual);
 
-	dev_dbg(drvdata->dev, "%s: %zu bytes copied, %d bytes left\n",
-		__func__, len, (int)(drvdata->len - *ppos));
-	return len;
+	return actual;
 }
 
 static int tmc_release(struct inode *inode, struct file *file)
diff --git a/drivers/hwtracing/coresight/coresight-tmc.h b/drivers/hwtracing/coresight/coresight-tmc.h
index dfaff077a7fc..1d7cd582919b 100644
--- a/drivers/hwtracing/coresight/coresight-tmc.h
+++ b/drivers/hwtracing/coresight/coresight-tmc.h
@@ -172,10 +172,14 @@ int tmc_read_unprepare_etb(struct tmc_drvdata *drvdata);
 extern const struct coresight_ops tmc_etb_cs_ops;
 extern const struct coresight_ops tmc_etf_cs_ops;
 
+ssize_t tmc_etb_get_sysfs_trace(struct tmc_drvdata *drvdata,
+				loff_t pos, size_t len, char **bufpp);
 /* ETR functions */
 int tmc_read_prepare_etr(struct tmc_drvdata *drvdata);
 int tmc_read_unprepare_etr(struct tmc_drvdata *drvdata);
 extern const struct coresight_ops tmc_etr_cs_ops;
+ssize_t tmc_etr_get_sysfs_trace(struct tmc_drvdata *drvdata,
+				loff_t pos, size_t len, char **bufpp);
 
 
 #define TMC_REG_PAIR(name, lo_off, hi_off)				\
-- 
2.7.4

[PATCH 06/25] coresight: tmc-etr: Do not clean trace buffer

[Mathieu Poirier]

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

We zero out the entire trace buffer used for ETR before it is enabled,
for helping with debugging. With the addition of scatter-gather mode,
the buffer could be bigger and non-contiguous.

Get rid of this step; if someone wants to debug, they can always add it
as and when needed.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
 drivers/hwtracing/coresight/coresight-tmc-etr.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
index f88342d400ef..1de05c9a01c8 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
@@ -13,9 +13,6 @@ static void tmc_etr_enable_hw(struct tmc_drvdata *drvdata)
 {
 	u32 axictl, sts;
 
-	/* Zero out the memory to help with debug */
-	memset(drvdata->vaddr, 0, drvdata->size);
-
 	CS_UNLOCK(drvdata->base);
 
 	/* Wait for TMCSReady bit to be set */
@@ -340,9 +337,8 @@ int tmc_read_unprepare_etr(struct tmc_drvdata *drvdata)
 	if (drvdata->mode == CS_MODE_SYSFS) {
 		/*
 		 * The trace run will continue with the same allocated trace
-		 * buffer. The trace buffer is cleared in tmc_etr_enable_hw(),
-		 * so we don't have to explicitly clear it. Also, since the
-		 * tracer is still enabled drvdata::buf can't be NULL.
+		 * buffer. Since the tracer is still enabled drvdata::buf can't
+		 * be NULL.
 		 */
 		tmc_etr_enable_hw(drvdata);
 	} else {
-- 
2.7.4

[PATCH 07/25] coresight: tmc-etr: Disallow perf mode

[Mathieu Poirier]

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

We don't support ETR in perf mode yet. So, don't
even try to enable the hardware, even by mistake.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
 drivers/hwtracing/coresight/coresight-tmc-etr.c | 28 ++-----------------------
 1 file changed, 2 insertions(+), 26 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
index 1de05c9a01c8..18c9a184d31a 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
@@ -211,32 +211,8 @@ static int tmc_enable_etr_sink_sysfs(struct coresight_device *csdev)
 
 static int tmc_enable_etr_sink_perf(struct coresight_device *csdev)
 {
-	int ret = 0;
-	unsigned long flags;
-	struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
-
-	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 ETR is already operated
-	 * from sysFS.
-	 */
-	if (drvdata->mode != CS_MODE_DISABLED) {
-		ret = -EINVAL;
-		goto out;
-	}
-
-	drvdata->mode = CS_MODE_PERF;
-	tmc_etr_enable_hw(drvdata);
-out:
-	spin_unlock_irqrestore(&drvdata->spinlock, flags);
-
-	return ret;
+	/* We don't support perf mode yet ! */
+	return -EINVAL;
 }
 
 static int tmc_enable_etr_sink(struct coresight_device *csdev, u32 mode)
-- 
2.7.4

[PATCH 08/25] coresight: Add helper for inserting synchronization packets

[Mathieu Poirier]

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

Right now we open code filling the trace buffer with synchronization
packets when the circular buffer wraps around in different drivers.
Move this to a common place. While at it, clean up the barrier_pkt
array to strip off the trailing '\0'.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
 drivers/hwtracing/coresight/coresight-etb10.c   | 12 ++++-------
 drivers/hwtracing/coresight/coresight-priv.h    | 10 ++++++++-
 drivers/hwtracing/coresight/coresight-tmc-etf.c | 27 ++++++++-----------------
 drivers/hwtracing/coresight/coresight-tmc-etr.c | 13 +-----------
 drivers/hwtracing/coresight/coresight.c         |  3 +--
 5 files changed, 23 insertions(+), 42 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-etb10.c b/drivers/hwtracing/coresight/coresight-etb10.c
index 320d29df17e1..306119eaf16a 100644
--- a/drivers/hwtracing/coresight/coresight-etb10.c
+++ b/drivers/hwtracing/coresight/coresight-etb10.c
@@ -195,7 +195,6 @@ static void etb_dump_hw(struct etb_drvdata *drvdata)
 	bool lost = false;
 	int i;
 	u8 *buf_ptr;
-	const u32 *barrier;
 	u32 read_data, depth;
 	u32 read_ptr, write_ptr;
 	u32 frame_off, frame_endoff;
@@ -226,19 +225,16 @@ static void etb_dump_hw(struct etb_drvdata *drvdata)
 
 	depth = drvdata->buffer_depth;
 	buf_ptr = drvdata->buf;
-	barrier = barrier_pkt;
 	for (i = 0; i < depth; i++) {
 		read_data = readl_relaxed(drvdata->base +
 					  ETB_RAM_READ_DATA_REG);
-		if (lost && *barrier) {
-			read_data = *barrier;
-			barrier++;
-		}
-
 		*(u32 *)buf_ptr = read_data;
 		buf_ptr += 4;
 	}
 
+	if (lost)
+		coresight_insert_barrier_packet(drvdata->buf);
+
 	if (frame_off) {
 		buf_ptr -= (frame_endoff * 4);
 		for (i = 0; i < frame_endoff; i++) {
@@ -447,7 +443,7 @@ static void etb_update_buffer(struct coresight_device *csdev,
 		buf_ptr = buf->data_pages[cur] + offset;
 		read_data = readl_relaxed(drvdata->base +
 					  ETB_RAM_READ_DATA_REG);
-		if (lost && *barrier) {
+		if (lost && i < CORESIGHT_BARRIER_PKT_SIZE) {
 			read_data = *barrier;
 			barrier++;
 		}
diff --git a/drivers/hwtracing/coresight/coresight-priv.h b/drivers/hwtracing/coresight/coresight-priv.h
index 0e5a74dae6a6..1a6cf3589866 100644
--- a/drivers/hwtracing/coresight/coresight-priv.h
+++ b/drivers/hwtracing/coresight/coresight-priv.h
@@ -57,7 +57,8 @@ static DEVICE_ATTR_RO(name)
 #define coresight_simple_reg64(type, name, lo_off, hi_off)		\
 	__coresight_simple_func(type, NULL, name, lo_off, hi_off)
 
-extern const u32 barrier_pkt[5];
+extern const u32 barrier_pkt[4];
+#define CORESIGHT_BARRIER_PKT_SIZE (sizeof(barrier_pkt))
 
 enum etm_addr_type {
 	ETM_ADDR_TYPE_NONE,
@@ -91,6 +92,13 @@ struct cs_buffers {
 	void			**data_pages;
 };
 
+static inline void coresight_insert_barrier_packet(void *buf)
+{
+	if (buf)
+		memcpy(buf, barrier_pkt, CORESIGHT_BARRIER_PKT_SIZE);
+}
+
+
 static inline void CS_LOCK(void __iomem *addr)
 {
 	do {
diff --git a/drivers/hwtracing/coresight/coresight-tmc-etf.c b/drivers/hwtracing/coresight/coresight-tmc-etf.c
index 73160cd0e0d1..0549249f4b39 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etf.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etf.c
@@ -32,39 +32,28 @@ static void tmc_etb_enable_hw(struct tmc_drvdata *drvdata)
 
 static void tmc_etb_dump_hw(struct tmc_drvdata *drvdata)
 {
-	bool lost = false;
 	char *bufp;
-	const u32 *barrier;
-	u32 read_data, status;
+	u32 read_data, lost;
 	int i;
 
-	/*
-	 * Get a hold of the status register and see if a wrap around
-	 * has occurred.
-	 */
-	status = readl_relaxed(drvdata->base + TMC_STS);
-	if (status & TMC_STS_FULL)
-		lost = true;
-
+	/* Check if the buffer wrapped around. */
+	lost = readl_relaxed(drvdata->base + TMC_STS) & TMC_STS_FULL;
 	bufp = drvdata->buf;
 	drvdata->len = 0;
-	barrier = barrier_pkt;
 	while (1) {
 		for (i = 0; i < drvdata->memwidth; i++) {
 			read_data = readl_relaxed(drvdata->base + TMC_RRD);
 			if (read_data == 0xFFFFFFFF)
-				return;
-
-			if (lost && *barrier) {
-				read_data = *barrier;
-				barrier++;
-			}
-
+				goto done;
 			memcpy(bufp, &read_data, 4);
 			bufp += 4;
 			drvdata->len += 4;
 		}
 	}
+done:
+	if (lost)
+		coresight_insert_barrier_packet(drvdata->buf);
+	return;
 }
 
 static void tmc_etb_disable_hw(struct tmc_drvdata *drvdata)
diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
index 18c9a184d31a..04206ff7a67c 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
@@ -91,9 +91,7 @@ ssize_t tmc_etr_get_sysfs_trace(struct tmc_drvdata *drvdata,
 
 static void tmc_etr_dump_hw(struct tmc_drvdata *drvdata)
 {
-	const u32 *barrier;
 	u32 val;
-	u32 *temp;
 	u64 rwp;
 
 	rwp = tmc_read_rwp(drvdata);
@@ -106,16 +104,7 @@ static void tmc_etr_dump_hw(struct tmc_drvdata *drvdata)
 	if (val & TMC_STS_FULL) {
 		drvdata->buf = drvdata->vaddr + rwp - drvdata->paddr;
 		drvdata->len = drvdata->size;
-
-		barrier = barrier_pkt;
-		temp = (u32 *)drvdata->buf;
-
-		while (*barrier) {
-			*temp = *barrier;
-			temp++;
-			barrier++;
-		}
-
+		coresight_insert_barrier_packet(drvdata->buf);
 	} else {
 		drvdata->buf = drvdata->vaddr;
 		drvdata->len = rwp - drvdata->paddr;
diff --git a/drivers/hwtracing/coresight/coresight.c b/drivers/hwtracing/coresight/coresight.c
index 29e834aab539..4969b329511c 100644
--- a/drivers/hwtracing/coresight/coresight.c
+++ b/drivers/hwtracing/coresight/coresight.c
@@ -51,8 +51,7 @@ static struct list_head *stm_path;
  * beginning of the data collected in a buffer.  That way the decoder knows that
  * it needs to look for another sync sequence.
  */
-const u32 barrier_pkt[5] = {0x7fffffff, 0x7fffffff,
-			    0x7fffffff, 0x7fffffff, 0x0};
+const u32 barrier_pkt[4] = {0x7fffffff, 0x7fffffff, 0x7fffffff, 0x7fffffff};
 
 static int coresight_id_match(struct device *dev, void *data)
 {
-- 
2.7.4

[PATCH 09/25] dts: bindings: Restrict coresight tmc-etr scatter-gather mode

[Mathieu Poirier]

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

We are about to add the support for ETR builtin scatter-gather mode
for dealing with large amount of trace buffers. However, on some of
the platforms, using the ETR SG mode can lock up the system due to
the way the ETR is connected to the memory subsystem.

In SG mode, the ETR performs READ from the scatter-gather table to
fetch the next page and regular WRITE of trace data. If the READ
operation doesn't complete(due to the memory subsystem issues,
which we have seen on a couple of platforms) the trace WRITE
cannot proceed leading to issues. So, we by default do not
use the SG mode, unless it is known to be safe on the platform.
We define a DT property for the TMC node to specify whether we
have a proper SG mode.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: John Horley <john.horley@arm.com>
Cc: Robert Walker <robert.walker@arm.com>
Cc: devicetree at vger.kernel.org
Cc: frowand.list at gmail.com
Reviewed-by: Rob Herring <robh@kernel.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 ++
 drivers/hwtracing/coresight/coresight-tmc.c         | 9 ++++++++-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/arm/coresight.txt b/Documentation/devicetree/bindings/arm/coresight.txt
index 15ac8e8dcfdf..603d3c62e8c7 100644
--- a/Documentation/devicetree/bindings/arm/coresight.txt
+++ b/Documentation/devicetree/bindings/arm/coresight.txt
@@ -86,6 +86,8 @@ its hardware characteristcs.
 	* arm,buffer-size: size of contiguous buffer space for TMC ETR
 	 (embedded trace router)
 
+	* arm,scatter-gather: boolean. Indicates that the TMC-ETR can safely
+	  use the SG mode on this system.
 
 Example:
 
diff --git a/drivers/hwtracing/coresight/coresight-tmc.c b/drivers/hwtracing/coresight/coresight-tmc.c
index bb57e7f57eb5..bc8fc860c473 100644
--- a/drivers/hwtracing/coresight/coresight-tmc.c
+++ b/drivers/hwtracing/coresight/coresight-tmc.c
@@ -12,6 +12,7 @@
 #include <linux/err.h>
 #include <linux/fs.h>
 #include <linux/miscdevice.h>
+#include <linux/property.h>
 #include <linux/uaccess.h>
 #include <linux/slab.h>
 #include <linux/dma-mapping.h>
@@ -296,6 +297,12 @@ const struct attribute_group *coresight_tmc_groups[] = {
 	NULL,
 };
 
+static inline bool tmc_etr_can_use_sg(struct tmc_drvdata *drvdata)
+{
+	return fwnode_property_present(drvdata->dev->fwnode,
+				       "arm,scatter-gather");
+}
+
 /* Detect and initialise the capabilities of a TMC ETR */
 static int tmc_etr_setup_caps(struct tmc_drvdata *drvdata,
 			     u32 devid, void *dev_caps)
@@ -305,7 +312,7 @@ static int tmc_etr_setup_caps(struct tmc_drvdata *drvdata,
 	/* Set the unadvertised capabilities */
 	tmc_etr_init_caps(drvdata, (u32)(unsigned long)dev_caps);
 
-	if (!(devid & TMC_DEVID_NOSCAT))
+	if (!(devid & TMC_DEVID_NOSCAT) && tmc_etr_can_use_sg(drvdata))
 		tmc_etr_set_cap(drvdata, TMC_ETR_SG);
 
 	/* Check if the AXI address width is available */
-- 
2.7.4

[PATCH 10/25] coresight: Add generic TMC sg table framework

[Mathieu Poirier]

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

This patch introduces a generic sg table data structure and
associated operations. An SG table can be used to map a set
of Data pages where the trace data could be stored by the TMC
ETR. The information about the data pages could be stored in
different formats, depending on the type of the underlying
SG mechanism (e.g, TMC ETR SG vs Coresight CATU). The generic
structure provides book keeping of the pages used for the data
as well as the table contents. The table should be filled by
the user of the infrastructure.

A table can be created by specifying the number of data pages
as well as the number of table pages required to hold the
pointers, where the latter could be different for different
types of tables. The pages are mapped in the appropriate dma
data direction mode (i.e, DMA_TO_DEVICE for table pages
and DMA_FROM_DEVICE for data pages).  The framework can optionally
accept a set of allocated data pages (e.g, perf ring buffer) and
map them accordingly. The table and data pages are vmap'ed to allow
easier access by the drivers. The framework also provides helpers to
sync the data written to the pages with appropriate directions.

This will be later used by the TMC ETR SG unit and CATU.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
 drivers/hwtracing/coresight/coresight-tmc-etr.c | 268 ++++++++++++++++++++++++
 drivers/hwtracing/coresight/coresight-tmc.h     |  50 +++++
 2 files changed, 318 insertions(+)

diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
index 04206ff7a67c..402b06143e10 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
@@ -6,9 +6,277 @@
 
 #include <linux/coresight.h>
 #include <linux/dma-mapping.h>
+#include <linux/slab.h>
 #include "coresight-priv.h"
 #include "coresight-tmc.h"
 
+/*
+ * tmc_pages_get_offset:  Go through all the pages in the tmc_pages
+ * and map the device address @addr to an offset within the virtual
+ * contiguous buffer.
+ */
+static long
+tmc_pages_get_offset(struct tmc_pages *tmc_pages, dma_addr_t addr)
+{
+	int i;
+	dma_addr_t page_start;
+
+	for (i = 0; i < tmc_pages->nr_pages; i++) {
+		page_start = tmc_pages->daddrs[i];
+		if (addr >= page_start && addr < (page_start + PAGE_SIZE))
+			return i * PAGE_SIZE + (addr - page_start);
+	}
+
+	return -EINVAL;
+}
+
+/*
+ * tmc_pages_free : Unmap and free the pages used by tmc_pages.
+ * If the pages were not allocated in tmc_pages_alloc(), we would
+ * simply drop the refcount.
+ */
+static void tmc_pages_free(struct tmc_pages *tmc_pages,
+			   struct device *dev, enum dma_data_direction dir)
+{
+	int i;
+
+	for (i = 0; i < tmc_pages->nr_pages; i++) {
+		if (tmc_pages->daddrs && tmc_pages->daddrs[i])
+			dma_unmap_page(dev, tmc_pages->daddrs[i],
+					 PAGE_SIZE, dir);
+		if (tmc_pages->pages && tmc_pages->pages[i])
+			__free_page(tmc_pages->pages[i]);
+	}
+
+	kfree(tmc_pages->pages);
+	kfree(tmc_pages->daddrs);
+	tmc_pages->pages = NULL;
+	tmc_pages->daddrs = NULL;
+	tmc_pages->nr_pages = 0;
+}
+
+/*
+ * tmc_pages_alloc : Allocate and map pages for a given @tmc_pages.
+ * If @pages is not NULL, the list of page virtual addresses are
+ * used as the data pages. The pages are then dma_map'ed for @dev
+ * with dma_direction @dir.
+ *
+ * Returns 0 upon success, else the error number.
+ */
+static int tmc_pages_alloc(struct tmc_pages *tmc_pages,
+			   struct device *dev, int node,
+			   enum dma_data_direction dir, void **pages)
+{
+	int i, nr_pages;
+	dma_addr_t paddr;
+	struct page *page;
+
+	nr_pages = tmc_pages->nr_pages;
+	tmc_pages->daddrs = kcalloc(nr_pages, sizeof(*tmc_pages->daddrs),
+					 GFP_KERNEL);
+	if (!tmc_pages->daddrs)
+		return -ENOMEM;
+	tmc_pages->pages = kcalloc(nr_pages, sizeof(*tmc_pages->pages),
+					 GFP_KERNEL);
+	if (!tmc_pages->pages) {
+		kfree(tmc_pages->daddrs);
+		tmc_pages->daddrs = NULL;
+		return -ENOMEM;
+	}
+
+	for (i = 0; i < nr_pages; i++) {
+		if (pages && pages[i]) {
+			page = virt_to_page(pages[i]);
+			/* Hold a refcount on the page */
+			get_page(page);
+		} else {
+			page = alloc_pages_node(node,
+						GFP_KERNEL | __GFP_ZERO, 0);
+		}
+		paddr = dma_map_page(dev, page, 0, PAGE_SIZE, dir);
+		if (dma_mapping_error(dev, paddr))
+			goto err;
+		tmc_pages->daddrs[i] = paddr;
+		tmc_pages->pages[i] = page;
+	}
+	return 0;
+err:
+	tmc_pages_free(tmc_pages, dev, dir);
+	return -ENOMEM;
+}
+
+static inline long
+tmc_sg_get_data_page_offset(struct tmc_sg_table *sg_table, dma_addr_t addr)
+{
+	return tmc_pages_get_offset(&sg_table->data_pages, addr);
+}
+
+static inline void tmc_free_table_pages(struct tmc_sg_table *sg_table)
+{
+	if (sg_table->table_vaddr)
+		vunmap(sg_table->table_vaddr);
+	tmc_pages_free(&sg_table->table_pages, sg_table->dev, DMA_TO_DEVICE);
+}
+
+static void tmc_free_data_pages(struct tmc_sg_table *sg_table)
+{
+	if (sg_table->data_vaddr)
+		vunmap(sg_table->data_vaddr);
+	tmc_pages_free(&sg_table->data_pages, sg_table->dev, DMA_FROM_DEVICE);
+}
+
+void tmc_free_sg_table(struct tmc_sg_table *sg_table)
+{
+	tmc_free_table_pages(sg_table);
+	tmc_free_data_pages(sg_table);
+}
+
+/*
+ * Alloc pages for the table. Since this will be used by the device,
+ * allocate the pages closer to the device (i.e, dev_to_node(dev)
+ * rather than the CPU node).
+ */
+static int tmc_alloc_table_pages(struct tmc_sg_table *sg_table)
+{
+	int rc;
+	struct tmc_pages *table_pages = &sg_table->table_pages;
+
+	rc = tmc_pages_alloc(table_pages, sg_table->dev,
+			     dev_to_node(sg_table->dev),
+			     DMA_TO_DEVICE, NULL);
+	if (rc)
+		return rc;
+	sg_table->table_vaddr = vmap(table_pages->pages,
+				     table_pages->nr_pages,
+				     VM_MAP,
+				     PAGE_KERNEL);
+	if (!sg_table->table_vaddr)
+		rc = -ENOMEM;
+	else
+		sg_table->table_daddr = table_pages->daddrs[0];
+	return rc;
+}
+
+static int tmc_alloc_data_pages(struct tmc_sg_table *sg_table, void **pages)
+{
+	int rc;
+
+	/* Allocate data pages on the node requested by the caller */
+	rc = tmc_pages_alloc(&sg_table->data_pages,
+			     sg_table->dev, sg_table->node,
+			     DMA_FROM_DEVICE, pages);
+	if (!rc) {
+		sg_table->data_vaddr = vmap(sg_table->data_pages.pages,
+					    sg_table->data_pages.nr_pages,
+					    VM_MAP,
+					    PAGE_KERNEL);
+		if (!sg_table->data_vaddr)
+			rc = -ENOMEM;
+	}
+	return rc;
+}
+
+/*
+ * tmc_alloc_sg_table: Allocate and setup dma pages for the TMC SG table
+ * and data buffers. TMC writes to the data buffers and reads from the SG
+ * Table pages.
+ *
+ * @dev		- Device to which page should be DMA mapped.
+ * @node	- Numa node for mem allocations
+ * @nr_tpages	- Number of pages for the table entries.
+ * @nr_dpages	- Number of pages for Data buffer.
+ * @pages	- Optional list of virtual address of pages.
+ */
+struct tmc_sg_table *tmc_alloc_sg_table(struct device *dev,
+					int node,
+					int nr_tpages,
+					int nr_dpages,
+					void **pages)
+{
+	long rc;
+	struct tmc_sg_table *sg_table;
+
+	sg_table = kzalloc(sizeof(*sg_table), GFP_KERNEL);
+	if (!sg_table)
+		return ERR_PTR(-ENOMEM);
+	sg_table->data_pages.nr_pages = nr_dpages;
+	sg_table->table_pages.nr_pages = nr_tpages;
+	sg_table->node = node;
+	sg_table->dev = dev;
+
+	rc  = tmc_alloc_data_pages(sg_table, pages);
+	if (!rc)
+		rc = tmc_alloc_table_pages(sg_table);
+	if (rc) {
+		tmc_free_sg_table(sg_table);
+		kfree(sg_table);
+		return ERR_PTR(rc);
+	}
+
+	return sg_table;
+}
+
+/*
+ * tmc_sg_table_sync_data_range: Sync the data buffer written
+ * by the device from @offset upto a @size bytes.
+ */
+void tmc_sg_table_sync_data_range(struct tmc_sg_table *table,
+				  u64 offset, u64 size)
+{
+	int i, index, start;
+	int npages = DIV_ROUND_UP(size, PAGE_SIZE);
+	struct device *dev = table->dev;
+	struct tmc_pages *data = &table->data_pages;
+
+	start = offset >> PAGE_SHIFT;
+	for (i = start; i < (start + npages); i++) {
+		index = i % data->nr_pages;
+		dma_sync_single_for_cpu(dev, data->daddrs[index],
+					PAGE_SIZE, DMA_FROM_DEVICE);
+	}
+}
+
+/* tmc_sg_sync_table: Sync the page table */
+void tmc_sg_table_sync_table(struct tmc_sg_table *sg_table)
+{
+	int i;
+	struct device *dev = sg_table->dev;
+	struct tmc_pages *table_pages = &sg_table->table_pages;
+
+	for (i = 0; i < table_pages->nr_pages; i++)
+		dma_sync_single_for_device(dev, table_pages->daddrs[i],
+					   PAGE_SIZE, DMA_TO_DEVICE);
+}
+
+/*
+ * tmc_sg_table_get_data: Get the buffer pointer for data @offset
+ * in the SG buffer. The @bufpp is updated to point to the buffer.
+ * Returns :
+ *	the length of linear data available at @offset.
+ *	or
+ *	<= 0 if no data is available.
+ */
+ssize_t tmc_sg_table_get_data(struct tmc_sg_table *sg_table,
+			      u64 offset, size_t len, char **bufpp)
+{
+	size_t size;
+	int pg_idx = offset >> PAGE_SHIFT;
+	int pg_offset = offset & (PAGE_SIZE - 1);
+	struct tmc_pages *data_pages = &sg_table->data_pages;
+
+	size = tmc_sg_table_buf_size(sg_table);
+	if (offset >= size)
+		return -EINVAL;
+
+	/* Make sure we don't go beyond the end */
+	len = (len < (size - offset)) ? len : size - offset;
+	/* Respect the page boundaries */
+	len = (len < (PAGE_SIZE - pg_offset)) ? len : (PAGE_SIZE - pg_offset);
+	if (len > 0)
+		*bufpp = page_address(data_pages->pages[pg_idx]) + pg_offset;
+	return len;
+}
+
 static void tmc_etr_enable_hw(struct tmc_drvdata *drvdata)
 {
 	u32 axictl, sts;
diff --git a/drivers/hwtracing/coresight/coresight-tmc.h b/drivers/hwtracing/coresight/coresight-tmc.h
index 1d7cd582919b..cdb668b4441d 100644
--- a/drivers/hwtracing/coresight/coresight-tmc.h
+++ b/drivers/hwtracing/coresight/coresight-tmc.h
@@ -7,6 +7,7 @@
 #ifndef _CORESIGHT_TMC_H
 #define _CORESIGHT_TMC_H
 
+#include <linux/dma-mapping.h>
 #include <linux/miscdevice.h>
 
 #define TMC_RSZ			0x004
@@ -160,6 +161,38 @@ struct tmc_drvdata {
 	u32			etr_caps;
 };
 
+/**
+ * struct tmc_pages - Collection of pages used for SG.
+ * @nr_pages:		Number of pages in the list.
+ * @daddrs:		Array of DMA'able page address.
+ * @pages:		Array pages for the buffer.
+ */
+struct tmc_pages {
+	int nr_pages;
+	dma_addr_t	*daddrs;
+	struct page	**pages;
+};
+
+/*
+ * struct tmc_sg_table - Generic SG table for TMC
+ * @dev:		Device for DMA allocations
+ * @table_vaddr:	Contiguous Virtual address for PageTable
+ * @data_vaddr:		Contiguous Virtual address for Data Buffer
+ * @table_daddr:	DMA address of the PageTable base
+ * @node:		Node for Page allocations
+ * @table_pages:	List of pages & dma address for Table
+ * @data_pages:		List of pages & dma address for Data
+ */
+struct tmc_sg_table {
+	struct device *dev;
+	void *table_vaddr;
+	void *data_vaddr;
+	dma_addr_t table_daddr;
+	int node;
+	struct tmc_pages table_pages;
+	struct tmc_pages data_pages;
+};
+
 /* Generic functions */
 void tmc_wait_for_tmcready(struct tmc_drvdata *drvdata);
 void tmc_flush_and_stop(struct tmc_drvdata *drvdata);
@@ -215,4 +248,21 @@ static inline bool tmc_etr_has_cap(struct tmc_drvdata *drvdata, u32 cap)
 	return !!(drvdata->etr_caps & cap);
 }
 
+struct tmc_sg_table *tmc_alloc_sg_table(struct device *dev,
+					int node,
+					int nr_tpages,
+					int nr_dpages,
+					void **pages);
+void tmc_free_sg_table(struct tmc_sg_table *sg_table);
+void tmc_sg_table_sync_table(struct tmc_sg_table *sg_table);
+void tmc_sg_table_sync_data_range(struct tmc_sg_table *table,
+				  u64 offset, u64 size);
+ssize_t tmc_sg_table_get_data(struct tmc_sg_table *sg_table,
+			      u64 offset, size_t len, char **bufpp);
+static inline unsigned long
+tmc_sg_table_buf_size(struct tmc_sg_table *sg_table)
+{
+	return sg_table->data_pages.nr_pages << PAGE_SHIFT;
+}
+
 #endif
-- 
2.7.4

[PATCH 11/25] coresight: Add support for TMC ETR SG unit

[Mathieu Poirier]

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

This patch adds support for setting up an SG table used by the
TMC ETR inbuilt SG unit. The TMC ETR uses 4K page sized tables
to hold pointers to the 4K data pages with the last entry in a
table pointing to the next table with the entries, by kind of
chaining. The 2 LSBs determine the type of the table entry, to
one of :

 Normal - Points to a 4KB data page.
 Last   - Points to a 4KB data page, but is the last entry in the
          page table.
 Link   - Points to another 4KB table page with pointers to data.

The code takes care of handling the system page size which could
be different than 4K. So we could end up putting multiple ETR
SG tables in a single system page, vice versa for the data pages.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
 drivers/hwtracing/coresight/coresight-tmc-etr.c | 263 ++++++++++++++++++++++++
 1 file changed, 263 insertions(+)

diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
index 402b06143e10..54d5c0664277 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
@@ -11,6 +11,87 @@
 #include "coresight-tmc.h"
 
 /*
+ * 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
+ * contain more than one SG buffer and tables.
+ *
+ * A table entry has the following format:
+ *
+ * ---Bit31------------Bit4-------Bit1-----Bit0--
+ * |     Address[39:12]    | SBZ |  Entry Type  |
+ * ----------------------------------------------
+ *
+ * Address: Bits [39:12] of a physical page address. Bits [11:0] are
+ *	    always zero.
+ *
+ * Entry type:
+ *	b00 - Reserved.
+ *	b01 - Last entry in the tables, points to 4K page buffer.
+ *	b10 - Normal entry, points to 4K page buffer.
+ *	b11 - Link. The address points to the base of next table.
+ */
+
+typedef u32 sgte_t;
+
+#define ETR_SG_PAGE_SHIFT		12
+#define ETR_SG_PAGE_SIZE		(1UL << ETR_SG_PAGE_SHIFT)
+#define ETR_SG_PAGES_PER_SYSPAGE	(PAGE_SIZE / ETR_SG_PAGE_SIZE)
+#define ETR_SG_PTRS_PER_PAGE		(ETR_SG_PAGE_SIZE / sizeof(sgte_t))
+#define ETR_SG_PTRS_PER_SYSPAGE		(PAGE_SIZE / sizeof(sgte_t))
+
+#define ETR_SG_ET_MASK			0x3
+#define ETR_SG_ET_LAST			0x1
+#define ETR_SG_ET_NORMAL		0x2
+#define ETR_SG_ET_LINK			0x3
+
+#define ETR_SG_ADDR_SHIFT		4
+
+#define ETR_SG_ENTRY(addr, type) \
+	(sgte_t)((((addr) >> ETR_SG_PAGE_SHIFT) << ETR_SG_ADDR_SHIFT) | \
+		 (type & ETR_SG_ET_MASK))
+
+#define ETR_SG_ADDR(entry) \
+	(((dma_addr_t)(entry) >> ETR_SG_ADDR_SHIFT) << ETR_SG_PAGE_SHIFT)
+#define ETR_SG_ET(entry)		((entry) & ETR_SG_ET_MASK)
+
+/*
+ * struct etr_sg_table : ETR SG Table
+ * @sg_table:		Generic SG Table holding the data/table pages.
+ * @hwaddr:		hwaddress used by the TMC, which is the base
+ *			address of the table.
+ */
+struct etr_sg_table {
+	struct tmc_sg_table	*sg_table;
+	dma_addr_t		hwaddr;
+};
+
+/*
+ * tmc_etr_sg_table_entries: Total number of table entries required to map
+ * @nr_pages system pages.
+ *
+ * We need to map @nr_pages * ETR_SG_PAGES_PER_SYSPAGE data pages.
+ * Each TMC page can map (ETR_SG_PTRS_PER_PAGE - 1) buffer pointers,
+ * with the last entry pointing to another page of table entries.
+ * If we spill over to a new page for mapping 1 entry, we could as
+ * well replace the link entry of the previous page with the last entry.
+ */
+static inline unsigned long __attribute_const__
+tmc_etr_sg_table_entries(int nr_pages)
+{
+	unsigned long nr_sgpages = nr_pages * ETR_SG_PAGES_PER_SYSPAGE;
+	unsigned long nr_sglinks = nr_sgpages / (ETR_SG_PTRS_PER_PAGE - 1);
+	/*
+	 * If we spill over to a new page for 1 entry, we could as well
+	 * make it the LAST entry in the previous page, skipping the Link
+	 * address.
+	 */
+	if (nr_sglinks && (nr_sgpages % (ETR_SG_PTRS_PER_PAGE - 1) < 2))
+		nr_sglinks--;
+	return nr_sgpages + nr_sglinks;
+}
+
+/*
  * tmc_pages_get_offset:  Go through all the pages in the tmc_pages
  * and map the device address @addr to an offset within the virtual
  * contiguous buffer.
@@ -277,6 +358,188 @@ ssize_t tmc_sg_table_get_data(struct tmc_sg_table *sg_table,
 	return len;
 }
 
+#ifdef ETR_SG_DEBUG
+/* Map a dma address to virtual address */
+static unsigned long
+tmc_sg_daddr_to_vaddr(struct tmc_sg_table *sg_table,
+		      dma_addr_t addr, bool table)
+{
+	long offset;
+	unsigned long base;
+	struct tmc_pages *tmc_pages;
+
+	if (table) {
+		tmc_pages = &sg_table->table_pages;
+		base = (unsigned long)sg_table->table_vaddr;
+	} else {
+		tmc_pages = &sg_table->data_pages;
+		base = (unsigned long)sg_table->data_vaddr;
+	}
+
+	offset = tmc_pages_get_offset(tmc_pages, addr);
+	if (offset < 0)
+		return 0;
+	return base + offset;
+}
+
+/* Dump the given sg_table */
+static void tmc_etr_sg_table_dump(struct etr_sg_table *etr_table)
+{
+	sgte_t *ptr;
+	int i = 0;
+	dma_addr_t addr;
+	struct tmc_sg_table *sg_table = etr_table->sg_table;
+
+	ptr = (sgte_t *)tmc_sg_daddr_to_vaddr(sg_table,
+					      etr_table->hwaddr, true);
+	while (ptr) {
+		addr = ETR_SG_ADDR(*ptr);
+		switch (ETR_SG_ET(*ptr)) {
+		case ETR_SG_ET_NORMAL:
+			dev_dbg(sg_table->dev,
+				"%05d: %p\t:[N] 0x%llx\n", i, ptr, addr);
+			ptr++;
+			break;
+		case ETR_SG_ET_LINK:
+			dev_dbg(sg_table->dev,
+				"%05d: *** %p\t:{L} 0x%llx ***\n",
+				 i, ptr, addr);
+			ptr = (sgte_t *)tmc_sg_daddr_to_vaddr(sg_table,
+							      addr, true);
+			break;
+		case ETR_SG_ET_LAST:
+			dev_dbg(sg_table->dev,
+				"%05d: ### %p\t:[L] 0x%llx ###\n",
+				 i, ptr, addr);
+			return;
+		default:
+			dev_dbg(sg_table->dev,
+				"%05d: xxx %p\t:[INVALID] 0x%llx xxx\n",
+				 i, ptr, addr);
+			return;
+		}
+		i++;
+	}
+	dev_dbg(sg_table->dev, "******* End of Table *****\n");
+}
+#else
+static inline void tmc_etr_sg_table_dump(struct etr_sg_table *etr_table) {}
+#endif
+
+/*
+ * Populate the SG Table page table entries from table/data
+ * pages allocated. Each Data page has ETR_SG_PAGES_PER_SYSPAGE SG pages.
+ * So does a Table page. So we keep track of indices of the tables
+ * in each system page and move the pointers accordingly.
+ */
+#define INC_IDX_ROUND(idx, size) ((idx) = ((idx) + 1) % (size))
+static void tmc_etr_sg_table_populate(struct etr_sg_table *etr_table)
+{
+	dma_addr_t paddr;
+	int i, type, nr_entries;
+	int tpidx = 0; /* index to the current system table_page */
+	int sgtidx = 0;	/* index to the sg_table within the current syspage */
+	int sgtentry = 0; /* the entry within the sg_table */
+	int dpidx = 0; /* index to the current system data_page */
+	int spidx = 0; /* index to the SG page within the current data page */
+	sgte_t *ptr; /* pointer to the table entry to fill */
+	struct tmc_sg_table *sg_table = etr_table->sg_table;
+	dma_addr_t *table_daddrs = sg_table->table_pages.daddrs;
+	dma_addr_t *data_daddrs = sg_table->data_pages.daddrs;
+
+	nr_entries = tmc_etr_sg_table_entries(sg_table->data_pages.nr_pages);
+	/*
+	 * Use the contiguous virtual address of the table to update entries.
+	 */
+	ptr = sg_table->table_vaddr;
+	/*
+	 * Fill all the entries, except the last entry to avoid special
+	 * checks within the loop.
+	 */
+	for (i = 0; i < nr_entries - 1; i++) {
+		if (sgtentry == ETR_SG_PTRS_PER_PAGE - 1) {
+			/*
+			 * Last entry in a sg_table page is a link address to
+			 * the next table page. If this sg_table is the last
+			 * one in the system page, it links to the first
+			 * sg_table in the next system page. Otherwise, it
+			 * links to the next sg_table page within the system
+			 * page.
+			 */
+			if (sgtidx == ETR_SG_PAGES_PER_SYSPAGE - 1) {
+				paddr = table_daddrs[tpidx + 1];
+			} else {
+				paddr = table_daddrs[tpidx] +
+					(ETR_SG_PAGE_SIZE * (sgtidx + 1));
+			}
+			type = ETR_SG_ET_LINK;
+		} else {
+			/*
+			 * Update the indices to the data_pages to point to the
+			 * next sg_page in the data buffer.
+			 */
+			type = ETR_SG_ET_NORMAL;
+			paddr = data_daddrs[dpidx] + spidx * ETR_SG_PAGE_SIZE;
+			if (!INC_IDX_ROUND(spidx, ETR_SG_PAGES_PER_SYSPAGE))
+				dpidx++;
+		}
+		*ptr++ = ETR_SG_ENTRY(paddr, type);
+		/*
+		 * Move to the next table pointer, moving the table page index
+		 * if necessary
+		 */
+		if (!INC_IDX_ROUND(sgtentry, ETR_SG_PTRS_PER_PAGE)) {
+			if (!INC_IDX_ROUND(sgtidx, ETR_SG_PAGES_PER_SYSPAGE))
+				tpidx++;
+		}
+	}
+
+	/* Set up the last entry, which is always a data pointer */
+	paddr = data_daddrs[dpidx] + spidx * ETR_SG_PAGE_SIZE;
+	*ptr++ = ETR_SG_ENTRY(paddr, ETR_SG_ET_LAST);
+}
+
+/*
+ * tmc_init_etr_sg_table: Allocate a TMC ETR SG table, data buffer of @size and
+ * populate the table.
+ *
+ * @dev		- Device pointer for the TMC
+ * @node	- NUMA node where the memory should be allocated
+ * @size	- Total size of the data buffer
+ * @pages	- Optional list of page virtual address
+ */
+static struct etr_sg_table __maybe_unused *
+tmc_init_etr_sg_table(struct device *dev, int node,
+		      unsigned long size, void **pages)
+{
+	int nr_entries, nr_tpages;
+	int nr_dpages = size >> PAGE_SHIFT;
+	struct tmc_sg_table *sg_table;
+	struct etr_sg_table *etr_table;
+
+	etr_table = kzalloc(sizeof(*etr_table), GFP_KERNEL);
+	if (!etr_table)
+		return ERR_PTR(-ENOMEM);
+	nr_entries = tmc_etr_sg_table_entries(nr_dpages);
+	nr_tpages = DIV_ROUND_UP(nr_entries, ETR_SG_PTRS_PER_SYSPAGE);
+
+	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));
+	}
+
+	etr_table->sg_table = sg_table;
+	/* TMC should use table base address for DBA */
+	etr_table->hwaddr = sg_table->table_daddr;
+	tmc_etr_sg_table_populate(etr_table);
+	/* Sync the table pages for the HW */
+	tmc_sg_table_sync_table(sg_table);
+	tmc_etr_sg_table_dump(etr_table);
+
+	return etr_table;
+}
+
 static void tmc_etr_enable_hw(struct tmc_drvdata *drvdata)
 {
 	u32 axictl, sts;
-- 
2.7.4

[PATCH 12/25] coresight: tmc-etr: Add transparent buffer management

[Mathieu Poirier]

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

The TMC-ETR can use the target trace buffer in two different modes.
Normal physically contiguous mode and a discontiguous list pages in
Scatter-Gather mode. Also we have dedicated Coresight component, CATU
(Coresight Address Translation Unit) to provide improved scatter-gather
mode in Coresight SoC-600. This complicates the management of the
buffer used for trace, depending on the mode in which ETR is configured.

So, this patch adds a transparent layer for managing the ETR buffer
which abstracts the basic operations on the buffer (alloc, free,
sync and retrieve the data) and uses the mode specific helpers to
do the actual operation. This also allows the ETR driver to choose
the best mode for a given use case and adds the flexibility to
fallback to a different mode, without duplicating the code.

The patch also adds the "normal" flat memory mode and switches
the sysfs driver to use the new layer.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
 drivers/hwtracing/coresight/coresight-tmc-etr.c | 342 ++++++++++++++++++------
 drivers/hwtracing/coresight/coresight-tmc.h     |  55 +++-
 2 files changed, 308 insertions(+), 89 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
index 54d5c0664277..fba659dd2ee0 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
@@ -6,10 +6,18 @@
 
 #include <linux/coresight.h>
 #include <linux/dma-mapping.h>
+#include <linux/iommu.h>
 #include <linux/slab.h>
 #include "coresight-priv.h"
 #include "coresight-tmc.h"
 
+struct etr_flat_buf {
+	struct device	*dev;
+	dma_addr_t	daddr;
+	void		*vaddr;
+	size_t		size;
+};
+
 /*
  * 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
@@ -540,16 +548,207 @@ tmc_init_etr_sg_table(struct device *dev, int node,
 	return etr_table;
 }
 
+/*
+ * tmc_etr_alloc_flat_buf: Allocate a contiguous DMA buffer.
+ */
+static int tmc_etr_alloc_flat_buf(struct tmc_drvdata *drvdata,
+				  struct etr_buf *etr_buf, int node,
+				  void **pages)
+{
+	struct etr_flat_buf *flat_buf;
+
+	/* We cannot reuse existing pages for flat buf */
+	if (pages)
+		return -EINVAL;
+
+	flat_buf = kzalloc(sizeof(*flat_buf), GFP_KERNEL);
+	if (!flat_buf)
+		return -ENOMEM;
+
+	flat_buf->vaddr = dma_alloc_coherent(drvdata->dev, etr_buf->size,
+					     &flat_buf->daddr, GFP_KERNEL);
+	if (!flat_buf->vaddr) {
+		kfree(flat_buf);
+		return -ENOMEM;
+	}
+
+	flat_buf->size = etr_buf->size;
+	flat_buf->dev = drvdata->dev;
+	etr_buf->hwaddr = flat_buf->daddr;
+	etr_buf->mode = ETR_MODE_FLAT;
+	etr_buf->private = flat_buf;
+	return 0;
+}
+
+static void tmc_etr_free_flat_buf(struct etr_buf *etr_buf)
+{
+	struct etr_flat_buf *flat_buf = etr_buf->private;
+
+	if (flat_buf && flat_buf->daddr)
+		dma_free_coherent(flat_buf->dev, flat_buf->size,
+				  flat_buf->vaddr, flat_buf->daddr);
+	kfree(flat_buf);
+}
+
+static void tmc_etr_sync_flat_buf(struct etr_buf *etr_buf, u64 rrp, u64 rwp)
+{
+	/*
+	 * Adjust the buffer to point to the beginning of the trace data
+	 * and update the available trace data.
+	 */
+	etr_buf->offset = rrp - etr_buf->hwaddr;
+	if (etr_buf->full)
+		etr_buf->len = etr_buf->size;
+	else
+		etr_buf->len = rwp - rrp;
+}
+
+static ssize_t tmc_etr_get_data_flat_buf(struct etr_buf *etr_buf,
+					 u64 offset, size_t len, char **bufpp)
+{
+	struct etr_flat_buf *flat_buf = etr_buf->private;
+
+	*bufpp = (char *)flat_buf->vaddr + offset;
+	/*
+	 * tmc_etr_buf_get_data already adjusts the length to handle
+	 * buffer wrapping around.
+	 */
+	return len;
+}
+
+static const struct etr_buf_operations etr_flat_buf_ops = {
+	.alloc = tmc_etr_alloc_flat_buf,
+	.free = tmc_etr_free_flat_buf,
+	.sync = tmc_etr_sync_flat_buf,
+	.get_data = tmc_etr_get_data_flat_buf,
+};
+
+static const struct etr_buf_operations *etr_buf_ops[] = {
+	[ETR_MODE_FLAT] = &etr_flat_buf_ops,
+};
+
+static inline int tmc_etr_mode_alloc_buf(int mode,
+					 struct tmc_drvdata *drvdata,
+					 struct etr_buf *etr_buf, int node,
+					 void **pages)
+{
+	int rc;
+
+	switch (mode) {
+	case ETR_MODE_FLAT:
+		rc = etr_buf_ops[mode]->alloc(drvdata, etr_buf, node, pages);
+		if (!rc)
+			etr_buf->ops = etr_buf_ops[mode];
+		return rc;
+	default:
+		return -EINVAL;
+	}
+}
+
+/*
+ * tmc_alloc_etr_buf: Allocate a buffer use by ETR.
+ * @drvdata	: ETR device details.
+ * @size	: size of the requested buffer.
+ * @flags	: Required properties for the buffer.
+ * @node	: Node for memory allocations.
+ * @pages	: An optional list of pages.
+ */
+static struct etr_buf *tmc_alloc_etr_buf(struct tmc_drvdata *drvdata,
+					 ssize_t size, int flags,
+					 int node, void **pages)
+{
+	int rc = 0;
+	struct etr_buf *etr_buf;
+
+	etr_buf = kzalloc(sizeof(*etr_buf), GFP_KERNEL);
+	if (!etr_buf)
+		return ERR_PTR(-ENOMEM);
+
+	etr_buf->size = size;
+
+	rc = tmc_etr_mode_alloc_buf(ETR_MODE_FLAT, drvdata,
+				    etr_buf, node, pages);
+	if (rc) {
+		kfree(etr_buf);
+		return ERR_PTR(rc);
+	}
+
+	return etr_buf;
+}
+
+static void tmc_free_etr_buf(struct etr_buf *etr_buf)
+{
+	WARN_ON(!etr_buf->ops || !etr_buf->ops->free);
+	etr_buf->ops->free(etr_buf);
+	kfree(etr_buf);
+}
+
+/*
+ * tmc_etr_buf_get_data: Get the pointer the trace data at @offset
+ * with a maximum of @len bytes.
+ * Returns: The size of the linear data available @pos, with *bufpp
+ * updated to point to the buffer.
+ */
+static ssize_t tmc_etr_buf_get_data(struct etr_buf *etr_buf,
+				    u64 offset, size_t len, char **bufpp)
+{
+	/* Adjust the length to limit this transaction to end of buffer */
+	len = (len < (etr_buf->size - offset)) ? len : etr_buf->size - offset;
+
+	return etr_buf->ops->get_data(etr_buf, (u64)offset, len, bufpp);
+}
+
+static inline s64
+tmc_etr_buf_insert_barrier_packet(struct etr_buf *etr_buf, u64 offset)
+{
+	ssize_t len;
+	char *bufp;
+
+	len = tmc_etr_buf_get_data(etr_buf, offset,
+				   CORESIGHT_BARRIER_PKT_SIZE, &bufp);
+	if (WARN_ON(len <= CORESIGHT_BARRIER_PKT_SIZE))
+		return -EINVAL;
+	coresight_insert_barrier_packet(bufp);
+	return offset + CORESIGHT_BARRIER_PKT_SIZE;
+}
+
+/*
+ * tmc_sync_etr_buf: Sync the trace buffer availability with drvdata.
+ * Makes sure the trace data is synced to the memory for consumption.
+ * @etr_buf->offset will hold the offset to the beginning of the trace data
+ * within the buffer, with @etr_buf->len bytes to consume.
+ */
+static void tmc_sync_etr_buf(struct tmc_drvdata *drvdata)
+{
+	struct etr_buf *etr_buf = drvdata->etr_buf;
+	u64 rrp, rwp;
+	u32 status;
+
+	rrp = tmc_read_rrp(drvdata);
+	rwp = tmc_read_rwp(drvdata);
+	status = readl_relaxed(drvdata->base + TMC_STS);
+	etr_buf->full = status & TMC_STS_FULL;
+
+	WARN_ON(!etr_buf->ops || !etr_buf->ops->sync);
+
+	etr_buf->ops->sync(etr_buf, rrp, rwp);
+
+	/* Insert barrier packets at the beginning, if there was an overflow */
+	if (etr_buf->full)
+		tmc_etr_buf_insert_barrier_packet(etr_buf, etr_buf->offset);
+}
+
 static void tmc_etr_enable_hw(struct tmc_drvdata *drvdata)
 {
 	u32 axictl, sts;
+	struct etr_buf *etr_buf = drvdata->etr_buf;
 
 	CS_UNLOCK(drvdata->base);
 
 	/* Wait for TMCSReady bit to be set */
 	tmc_wait_for_tmcready(drvdata);
 
-	writel_relaxed(drvdata->size / 4, drvdata->base + TMC_RSZ);
+	writel_relaxed(etr_buf->size / 4, drvdata->base + TMC_RSZ);
 	writel_relaxed(TMC_MODE_CIRCULAR_BUFFER, drvdata->base + TMC_MODE);
 
 	axictl = readl_relaxed(drvdata->base + TMC_AXICTL);
@@ -563,15 +762,15 @@ static void tmc_etr_enable_hw(struct tmc_drvdata *drvdata)
 	}
 
 	writel_relaxed(axictl, drvdata->base + TMC_AXICTL);
-	tmc_write_dba(drvdata, drvdata->paddr);
+	tmc_write_dba(drvdata, etr_buf->hwaddr);
 	/*
 	 * If the TMC pointers must be programmed before the session,
 	 * we have to set it properly (i.e, RRP/RWP to base address and
 	 * STS to "not full").
 	 */
 	if (tmc_etr_has_cap(drvdata, TMC_ETR_SAVE_RESTORE)) {
-		tmc_write_rrp(drvdata, drvdata->paddr);
-		tmc_write_rwp(drvdata, drvdata->paddr);
+		tmc_write_rrp(drvdata, etr_buf->hwaddr);
+		tmc_write_rwp(drvdata, etr_buf->hwaddr);
 		sts = readl_relaxed(drvdata->base + TMC_STS) & ~TMC_STS_FULL;
 		writel_relaxed(sts, drvdata->base + TMC_STS);
 	}
@@ -587,59 +786,48 @@ static void tmc_etr_enable_hw(struct tmc_drvdata *drvdata)
 }
 
 /*
- * Return the available trace data in the buffer @pos, with a maximum
- * limit of @len, also updating the @bufpp on where to find it.
+ * 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,
+ * 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.
  */
 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;
-	char *bufp = drvdata->buf + pos;
-	char *bufend = (char *)(drvdata->vaddr + drvdata->size);
-
-	/* Adjust the len to available size @pos */
-	if (pos + actual > drvdata->len)
-		actual = drvdata->len - pos;
+	struct etr_buf *etr_buf = drvdata->etr_buf;
 
+	if (pos + actual > etr_buf->len)
+		actual = etr_buf->len - pos;
 	if (actual <= 0)
 		return actual;
 
-	/*
-	 * Since we use a circular buffer, with trace data starting
-	 * @drvdata->buf, possibly anywhere in the buffer @drvdata->vaddr,
-	 * wrap the current @pos to within the buffer.
-	 */
-	if (bufp >= bufend)
-		bufp -= drvdata->size;
-	/*
-	 * For simplicity, avoid copying over a wrapped around buffer.
-	 */
-	if ((bufp + actual) > bufend)
-		actual = bufend - bufp;
-	*bufpp = bufp;
-	return actual;
+	/* Compute the offset from which we read the data */
+	offset = etr_buf->offset + pos;
+	if (offset >= etr_buf->size)
+		offset -= etr_buf->size;
+	return tmc_etr_buf_get_data(etr_buf, offset, actual, bufpp);
 }
 
-static void tmc_etr_dump_hw(struct tmc_drvdata *drvdata)
+static struct etr_buf *
+tmc_etr_setup_sysfs_buf(struct tmc_drvdata *drvdata)
 {
-	u32 val;
-	u64 rwp;
+	return tmc_alloc_etr_buf(drvdata, drvdata->size,
+				 0, cpu_to_node(0), NULL);
+}
 
-	rwp = tmc_read_rwp(drvdata);
-	val = readl_relaxed(drvdata->base + TMC_STS);
+static void
+tmc_etr_free_sysfs_buf(struct etr_buf *buf)
+{
+	if (buf)
+		tmc_free_etr_buf(buf);
+}
 
-	/*
-	 * Adjust the buffer to point to the beginning of the trace data
-	 * and update the available trace data.
-	 */
-	if (val & TMC_STS_FULL) {
-		drvdata->buf = drvdata->vaddr + rwp - drvdata->paddr;
-		drvdata->len = drvdata->size;
-		coresight_insert_barrier_packet(drvdata->buf);
-	} else {
-		drvdata->buf = drvdata->vaddr;
-		drvdata->len = rwp - drvdata->paddr;
-	}
+static void tmc_etr_sync_sysfs_buf(struct tmc_drvdata *drvdata)
+{
+	tmc_sync_etr_buf(drvdata);
 }
 
 static void tmc_etr_disable_hw(struct tmc_drvdata *drvdata)
@@ -652,7 +840,8 @@ static void tmc_etr_disable_hw(struct tmc_drvdata *drvdata)
 	 * read before the TMC is disabled.
 	 */
 	if (drvdata->mode == CS_MODE_SYSFS)
-		tmc_etr_dump_hw(drvdata);
+		tmc_etr_sync_sysfs_buf(drvdata);
+
 	tmc_disable_hw(drvdata);
 
 	CS_LOCK(drvdata->base);
@@ -661,35 +850,32 @@ static void tmc_etr_disable_hw(struct tmc_drvdata *drvdata)
 static int tmc_enable_etr_sink_sysfs(struct coresight_device *csdev)
 {
 	int ret = 0;
-	bool used = false;
 	unsigned long flags;
-	void __iomem *vaddr = NULL;
-	dma_addr_t paddr = 0;
 	struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
+	struct etr_buf *new_buf = NULL, *free_buf = NULL;
 
 	/*
-	 * If we don't have a buffer release the lock and allocate memory.
-	 * Otherwise keep the lock and move along.
+	 * If we are enabling the ETR from disabled state, we need to make
+	 * sure we have a buffer with the right size. The etr_buf is not reset
+	 * immediately after we stop the tracing in SYSFS mode as we wait for
+	 * the user to collect the data. We may be able to reuse the existing
+	 * buffer, provided the size matches. Any allocation has to be done
+	 * with the lock released.
 	 */
 	spin_lock_irqsave(&drvdata->spinlock, flags);
-	if (!drvdata->vaddr) {
+	if (!drvdata->etr_buf || (drvdata->etr_buf->size != drvdata->size)) {
 		spin_unlock_irqrestore(&drvdata->spinlock, flags);
 
-		/*
-		 * Contiguous  memory can't be allocated while a spinlock is
-		 * held.  As such allocate memory here and free it if a buffer
-		 * has already been allocated (from a previous session).
-		 */
-		vaddr = dma_alloc_coherent(drvdata->dev, drvdata->size,
-					   &paddr, GFP_KERNEL);
-		if (!vaddr)
-			return -ENOMEM;
+		/* Allocate memory with the locks released */
+		free_buf = new_buf = tmc_etr_setup_sysfs_buf(drvdata);
+		if (IS_ERR(new_buf))
+			return PTR_ERR(new_buf);
 
 		/* Let's try again */
 		spin_lock_irqsave(&drvdata->spinlock, flags);
 	}
 
-	if (drvdata->reading) {
+	if (drvdata->reading || drvdata->mode == CS_MODE_PERF) {
 		ret = -EBUSY;
 		goto out;
 	}
@@ -697,21 +883,19 @@ static int tmc_enable_etr_sink_sysfs(struct coresight_device *csdev)
 	/*
 	 * In sysFS mode we can have multiple writers per sink.  Since this
 	 * sink is already enabled no memory is needed and the HW need not be
-	 * touched.
+	 * touched, even if the buffer size has changed.
 	 */
 	if (drvdata->mode == CS_MODE_SYSFS)
 		goto out;
 
 	/*
-	 * If drvdata::vaddr == NULL, use the memory allocated above.
-	 * Otherwise a buffer still exists from a previous session, so
-	 * simply use that.
+	 * 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->vaddr == NULL) {
-		used = true;
-		drvdata->vaddr = vaddr;
-		drvdata->paddr = paddr;
-		drvdata->buf = drvdata->vaddr;
+	if (!drvdata->etr_buf ||
+	    (new_buf && drvdata->etr_buf->size != new_buf->size)) {
+		free_buf = drvdata->etr_buf;
+		drvdata->etr_buf = new_buf;
 	}
 
 	drvdata->mode = CS_MODE_SYSFS;
@@ -720,8 +904,8 @@ static int tmc_enable_etr_sink_sysfs(struct coresight_device *csdev)
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
 
 	/* Free memory outside the spinlock if need be */
-	if (!used && vaddr)
-		dma_free_coherent(drvdata->dev, drvdata->size, vaddr, paddr);
+	if (free_buf)
+		tmc_etr_free_sysfs_buf(free_buf);
 
 	if (!ret)
 		dev_info(drvdata->dev, "TMC-ETR enabled\n");
@@ -800,8 +984,8 @@ int tmc_read_prepare_etr(struct tmc_drvdata *drvdata)
 		goto out;
 	}
 
-	/* If drvdata::buf is NULL the trace data has been read already */
-	if (drvdata->buf == NULL) {
+	/* If drvdata::etr_buf is NULL the trace data has been read already */
+	if (drvdata->etr_buf == NULL) {
 		ret = -EINVAL;
 		goto out;
 	}
@@ -820,8 +1004,7 @@ int tmc_read_prepare_etr(struct tmc_drvdata *drvdata)
 int tmc_read_unprepare_etr(struct tmc_drvdata *drvdata)
 {
 	unsigned long flags;
-	dma_addr_t paddr;
-	void __iomem *vaddr = NULL;
+	struct etr_buf *etr_buf = NULL;
 
 	/* config types are set a boot time and never change */
 	if (WARN_ON_ONCE(drvdata->config_type != TMC_CONFIG_TYPE_ETR))
@@ -842,17 +1025,16 @@ int tmc_read_unprepare_etr(struct tmc_drvdata *drvdata)
 		 * The ETR is not tracing and the buffer was just read.
 		 * As such prepare to free the trace buffer.
 		 */
-		vaddr = drvdata->vaddr;
-		paddr = drvdata->paddr;
-		drvdata->buf = drvdata->vaddr = NULL;
+		etr_buf =  drvdata->etr_buf;
+		drvdata->etr_buf = NULL;
 	}
 
 	drvdata->reading = false;
 	spin_unlock_irqrestore(&drvdata->spinlock, flags);
 
 	/* Free allocated memory out side of the spinlock */
-	if (vaddr)
-		dma_free_coherent(drvdata->dev, drvdata->size, vaddr, paddr);
+	if (etr_buf)
+		tmc_free_etr_buf(etr_buf);
 
 	return 0;
 }
diff --git a/drivers/hwtracing/coresight/coresight-tmc.h b/drivers/hwtracing/coresight/coresight-tmc.h
index cdb668b4441d..bbd65e2107be 100644
--- a/drivers/hwtracing/coresight/coresight-tmc.h
+++ b/drivers/hwtracing/coresight/coresight-tmc.h
@@ -123,6 +123,34 @@ enum tmc_mem_intf_width {
 #define CORESIGHT_SOC_600_ETR_CAPS	\
 	(TMC_ETR_SAVE_RESTORE | TMC_ETR_AXI_ARCACHE)
 
+enum etr_mode {
+	ETR_MODE_FLAT,		/* Uses contiguous flat buffer */
+};
+
+struct etr_buf_operations;
+
+/**
+ * struct etr_buf - Details of the buffer used by ETR
+ * @mode	: Mode of the ETR buffer, contiguous, Scatter Gather etc.
+ * @full	: Trace data overflow
+ * @size	: Size of the buffer.
+ * @hwaddr	: Address to be programmed in the TMC:DBA{LO,HI}
+ * @offset	: Offset of the trace data in the buffer for consumption.
+ * @len		: Available trace data @buf (may round up to the beginning).
+ * @ops		: ETR buffer operations for the mode.
+ * @private	: Backend specific information for the buf
+ */
+struct etr_buf {
+	enum etr_mode			mode;
+	bool				full;
+	ssize_t				size;
+	dma_addr_t			hwaddr;
+	unsigned long			offset;
+	s64				len;
+	const struct etr_buf_operations	*ops;
+	void				*private;
+};
+
 /**
  * struct tmc_drvdata - specifics associated to an TMC component
  * @base:	memory mapped base address for this component.
@@ -130,11 +158,10 @@ enum tmc_mem_intf_width {
  * @csdev:	component vitals needed by the framework.
  * @miscdev:	specifics to handle "/dev/xyz.tmc" entry.
  * @spinlock:	only one at a time pls.
- * @buf:	area of memory where trace data get sent.
- * @paddr:	DMA start location in RAM.
- * @vaddr:	virtual representation of @paddr.
- * @size:	trace buffer size.
- * @len:	size of the available trace.
+ * @buf:	Snapshot of the trace data for ETF/ETB.
+ * @etr_buf:	details of buffer used in TMC-ETR
+ * @len:	size of the available trace for ETF/ETB.
+ * @size:	trace buffer size for this TMC (common for all modes).
  * @mode:	how this TMC is being used.
  * @config_type: TMC variant, must be of type @tmc_config_type.
  * @memwidth:	width of the memory interface databus, in bytes.
@@ -149,11 +176,12 @@ struct tmc_drvdata {
 	struct miscdevice	miscdev;
 	spinlock_t		spinlock;
 	bool			reading;
-	char			*buf;
-	dma_addr_t		paddr;
-	void __iomem		*vaddr;
-	u32			size;
+	union {
+		char		*buf;		/* TMC ETB */
+		struct etr_buf	*etr_buf;	/* TMC ETR */
+	};
 	u32			len;
+	u32			size;
 	u32			mode;
 	enum tmc_config_type	config_type;
 	enum tmc_mem_intf_width	memwidth;
@@ -161,6 +189,15 @@ struct tmc_drvdata {
 	u32			etr_caps;
 };
 
+struct etr_buf_operations {
+	int (*alloc)(struct tmc_drvdata *drvdata, struct etr_buf *etr_buf,
+		     int node, void **pages);
+	void (*sync)(struct etr_buf *etr_buf, u64 rrp, u64 rwp);
+	ssize_t (*get_data)(struct etr_buf *etr_buf, u64 offset, size_t len,
+			    char **bufpp);
+	void (*free)(struct etr_buf *etr_buf);
+};
+
 /**
  * struct tmc_pages - Collection of pages used for SG.
  * @nr_pages:		Number of pages in the list.
-- 
2.7.4

[PATCH 13/25] coresight: tmc-etr buf: Add TMC scatter gather mode backend

[Mathieu Poirier]

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

Add the support for Scatter-Gather mode to the etr-buf layer.
Since we now have two different modes, we choose the backend
based on a set of conditions, documented in the code.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
 drivers/hwtracing/coresight/coresight-tmc-etr.c | 114 +++++++++++++++++++++++-
 drivers/hwtracing/coresight/coresight-tmc.h     |   1 +
 2 files changed, 111 insertions(+), 4 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
index fba659dd2ee0..6164eed0b5fe 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
@@ -516,7 +516,7 @@ static void tmc_etr_sg_table_populate(struct etr_sg_table *etr_table)
  * @size	- Total size of the data buffer
  * @pages	- Optional list of page virtual address
  */
-static struct etr_sg_table __maybe_unused *
+static struct etr_sg_table *
 tmc_init_etr_sg_table(struct device *dev, int node,
 		      unsigned long size, void **pages)
 {
@@ -623,8 +623,86 @@ static const struct etr_buf_operations etr_flat_buf_ops = {
 	.get_data = tmc_etr_get_data_flat_buf,
 };
 
+/*
+ * tmc_etr_alloc_sg_buf: Allocate an SG buf @etr_buf. Setup the parameters
+ * appropriately.
+ */
+static int tmc_etr_alloc_sg_buf(struct tmc_drvdata *drvdata,
+				struct etr_buf *etr_buf, int node,
+				void **pages)
+{
+	struct etr_sg_table *etr_table;
+
+	etr_table = tmc_init_etr_sg_table(drvdata->dev, node,
+					  etr_buf->size, pages);
+	if (IS_ERR(etr_table))
+		return -ENOMEM;
+	etr_buf->hwaddr = etr_table->hwaddr;
+	etr_buf->mode = ETR_MODE_ETR_SG;
+	etr_buf->private = etr_table;
+	return 0;
+}
+
+static void tmc_etr_free_sg_buf(struct etr_buf *etr_buf)
+{
+	struct etr_sg_table *etr_table = etr_buf->private;
+
+	if (etr_table) {
+		tmc_free_sg_table(etr_table->sg_table);
+		kfree(etr_table);
+	}
+}
+
+static ssize_t tmc_etr_get_data_sg_buf(struct etr_buf *etr_buf, u64 offset,
+				       size_t len, char **bufpp)
+{
+	struct etr_sg_table *etr_table = etr_buf->private;
+
+	return tmc_sg_table_get_data(etr_table->sg_table, offset, len, bufpp);
+}
+
+static void tmc_etr_sync_sg_buf(struct etr_buf *etr_buf, u64 rrp, u64 rwp)
+{
+	long r_offset, w_offset;
+	struct etr_sg_table *etr_table = etr_buf->private;
+	struct tmc_sg_table *table = etr_table->sg_table;
+
+	/* Convert hw address to offset in the buffer */
+	r_offset = tmc_sg_get_data_page_offset(table, rrp);
+	if (r_offset < 0) {
+		dev_warn(table->dev,
+			 "Unable to map RRP %llx to offset\n", rrp);
+		etr_buf->len = 0;
+		return;
+	}
+
+	w_offset = tmc_sg_get_data_page_offset(table, rwp);
+	if (w_offset < 0) {
+		dev_warn(table->dev,
+			 "Unable to map RWP %llx to offset\n", rwp);
+		etr_buf->len = 0;
+		return;
+	}
+
+	etr_buf->offset = r_offset;
+	if (etr_buf->full)
+		etr_buf->len = etr_buf->size;
+	else
+		etr_buf->len = ((w_offset < r_offset) ? etr_buf->size : 0) +
+				w_offset - r_offset;
+	tmc_sg_table_sync_data_range(table, r_offset, etr_buf->len);
+}
+
+static const struct etr_buf_operations etr_sg_buf_ops = {
+	.alloc = tmc_etr_alloc_sg_buf,
+	.free = tmc_etr_free_sg_buf,
+	.sync = tmc_etr_sync_sg_buf,
+	.get_data = tmc_etr_get_data_sg_buf,
+};
+
 static const struct etr_buf_operations *etr_buf_ops[] = {
 	[ETR_MODE_FLAT] = &etr_flat_buf_ops,
+	[ETR_MODE_ETR_SG] = &etr_sg_buf_ops,
 };
 
 static inline int tmc_etr_mode_alloc_buf(int mode,
@@ -636,6 +714,7 @@ static inline int tmc_etr_mode_alloc_buf(int mode,
 
 	switch (mode) {
 	case ETR_MODE_FLAT:
+	case ETR_MODE_ETR_SG:
 		rc = etr_buf_ops[mode]->alloc(drvdata, etr_buf, node, pages);
 		if (!rc)
 			etr_buf->ops = etr_buf_ops[mode];
@@ -657,17 +736,38 @@ static struct etr_buf *tmc_alloc_etr_buf(struct tmc_drvdata *drvdata,
 					 ssize_t size, int flags,
 					 int node, void **pages)
 {
-	int rc = 0;
+	int rc = -ENOMEM;
+	bool has_etr_sg, has_iommu;
 	struct etr_buf *etr_buf;
 
+	has_etr_sg = tmc_etr_has_cap(drvdata, TMC_ETR_SG);
+	has_iommu = iommu_get_domain_for_dev(drvdata->dev);
+
 	etr_buf = kzalloc(sizeof(*etr_buf), GFP_KERNEL);
 	if (!etr_buf)
 		return ERR_PTR(-ENOMEM);
 
 	etr_buf->size = size;
 
-	rc = tmc_etr_mode_alloc_buf(ETR_MODE_FLAT, drvdata,
-				    etr_buf, node, pages);
+	/*
+	 * If we have to use an existing list of pages, we cannot reliably
+	 * use a contiguous DMA memory (even if we have an IOMMU). Otherwise,
+	 * we use the contiguous DMA memory if at least one of the following
+	 * conditions is true:
+	 *  a) The ETR cannot use Scatter-Gather.
+	 *  b) we have a backing IOMMU
+	 *  c) The requested memory size is smaller (< 1M).
+	 *
+	 * Fallback to available mechanisms.
+	 *
+	 */
+	if (!pages &&
+	    (!has_etr_sg || has_iommu || size < SZ_1M))
+		rc = tmc_etr_mode_alloc_buf(ETR_MODE_FLAT, drvdata,
+					    etr_buf, node, pages);
+	if (rc && has_etr_sg)
+		rc = tmc_etr_mode_alloc_buf(ETR_MODE_ETR_SG, drvdata,
+					    etr_buf, node, pages);
 	if (rc) {
 		kfree(etr_buf);
 		return ERR_PTR(rc);
@@ -761,6 +861,12 @@ 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;
+		axictl |= TMC_AXICTL_SCT_GAT_MODE;
+	}
+
 	writel_relaxed(axictl, drvdata->base + TMC_AXICTL);
 	tmc_write_dba(drvdata, etr_buf->hwaddr);
 	/*
diff --git a/drivers/hwtracing/coresight/coresight-tmc.h b/drivers/hwtracing/coresight/coresight-tmc.h
index bbd65e2107be..e7456575bfc1 100644
--- a/drivers/hwtracing/coresight/coresight-tmc.h
+++ b/drivers/hwtracing/coresight/coresight-tmc.h
@@ -125,6 +125,7 @@ enum tmc_mem_intf_width {
 
 enum etr_mode {
 	ETR_MODE_FLAT,		/* Uses contiguous flat buffer */
+	ETR_MODE_ETR_SG,	/* Uses in-built TMC ETR SG mechanism */
 };
 
 struct etr_buf_operations;
-- 
2.7.4

[PATCH 14/25] coresight: tmc: Add configuration support for trace buffer size

[Mathieu Poirier]

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

Now that we can dynamically switch between contiguous memory and
SG table depending on the trace buffer size, provide the support
for selecting an appropriate buffer size.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
 .../ABI/testing/sysfs-bus-coresight-devices-tmc    |  8 ++++++
 .../devicetree/bindings/arm/coresight.txt          |  3 +-
 drivers/hwtracing/coresight/coresight-tmc.c        | 33 ++++++++++++++++++++++
 3 files changed, 43 insertions(+), 1 deletion(-)

diff --git a/Documentation/ABI/testing/sysfs-bus-coresight-devices-tmc b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tmc
index 4fe677ed1305..ab49b9ac3bcb 100644
--- a/Documentation/ABI/testing/sysfs-bus-coresight-devices-tmc
+++ b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tmc
@@ -83,3 +83,11 @@ KernelVersion:	4.7
 Contact:	Mathieu Poirier <mathieu.poirier@linaro.org>
 Description:	(R) Indicates the capabilities of the Coresight TMC.
 		The value is read directly from the DEVID register, 0xFC8,
+
+What:		/sys/bus/coresight/devices/<memory_map>.tmc/buffer_size
+Date:		December 2018
+KernelVersion:	4.19
+Contact:	Mathieu Poirier <mathieu.poirier@linaro.org>
+Description:	(RW) Size of the trace buffer for TMC-ETR when used in SYSFS
+		mode. Writable only for TMC-ETR configurations. The value
+		should be aligned to the kernel pagesize.
diff --git a/Documentation/devicetree/bindings/arm/coresight.txt b/Documentation/devicetree/bindings/arm/coresight.txt
index 603d3c62e8c7..9aa30a156b57 100644
--- a/Documentation/devicetree/bindings/arm/coresight.txt
+++ b/Documentation/devicetree/bindings/arm/coresight.txt
@@ -84,7 +84,8 @@ its hardware characteristcs.
 * Optional property for TMC:
 
 	* arm,buffer-size: size of contiguous buffer space for TMC ETR
-	 (embedded trace router)
+	  (embedded trace router). This property is obsolete. The buffer size
+	  can be configured dynamically via buffer_size property in sysfs.
 
 	* arm,scatter-gather: boolean. Indicates that the TMC-ETR can safely
 	  use the SG mode on this system.
diff --git a/drivers/hwtracing/coresight/coresight-tmc.c b/drivers/hwtracing/coresight/coresight-tmc.c
index bc8fc860c473..1b817ec1192c 100644
--- a/drivers/hwtracing/coresight/coresight-tmc.c
+++ b/drivers/hwtracing/coresight/coresight-tmc.c
@@ -277,8 +277,41 @@ static ssize_t trigger_cntr_store(struct device *dev,
 }
 static DEVICE_ATTR_RW(trigger_cntr);
 
+static ssize_t buffer_size_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct tmc_drvdata *drvdata = dev_get_drvdata(dev->parent);
+
+	return sprintf(buf, "%#x\n", drvdata->size);
+}
+
+static ssize_t buffer_size_store(struct device *dev,
+				 struct device_attribute *attr,
+				 const char *buf, size_t size)
+{
+	int ret;
+	unsigned long val;
+	struct tmc_drvdata *drvdata = dev_get_drvdata(dev->parent);
+
+	/* Only permitted for TMC-ETRs */
+	if (drvdata->config_type != TMC_CONFIG_TYPE_ETR)
+		return -EPERM;
+
+	ret = kstrtoul(buf, 0, &val);
+	if (ret)
+		return ret;
+	/* The buffer size should be page aligned */
+	if (val & (PAGE_SIZE - 1))
+		return -EINVAL;
+	drvdata->size = val;
+	return size;
+}
+
+static DEVICE_ATTR_RW(buffer_size);
+
 static struct attribute *coresight_tmc_attrs[] = {
 	&dev_attr_trigger_cntr.attr,
+	&dev_attr_buffer_size.attr,
 	NULL,
 };
 
-- 
2.7.4

[PATCH 15/25] coresight: include vmalloc.h for vmap/vunmap

[Mathieu Poirier]

From: Arnd Bergmann <arnd@arndb.de>

The newly introduced code fails to build in some configurations
unless we include the right headers:

drivers/hwtracing/coresight/coresight-tmc-etr.c: In function 'tmc_free_table_pages':
drivers/hwtracing/coresight/coresight-tmc-etr.c:206:3: error: implicit declaration of function 'vunmap'; did you mean 'iounmap'? [-Werror=implicit-function-declaration]

Fixes: 79613ae8715a ("coresight: Add generic TMC sg table framework")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
 drivers/hwtracing/coresight/coresight-tmc-etr.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
index 6164eed0b5fe..3556d9a849e9 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
@@ -8,6 +8,7 @@
 #include <linux/dma-mapping.h>
 #include <linux/iommu.h>
 #include <linux/slab.h>
+#include <linux/vmalloc.h>
 #include "coresight-priv.h"
 #include "coresight-tmc.h"
 
-- 
2.7.4

[PATCH 16/25] coresight: Fix check in coresight_tmc_etr_buf_insert_barrier_packet

[Mathieu Poirier]

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

We request for "CORESIGHT_BARRIER_PKT_SIZE" length and we should
be happy when we get that size.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
 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 3556d9a849e9..8af451230121 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
@@ -807,7 +807,7 @@ tmc_etr_buf_insert_barrier_packet(struct etr_buf *etr_buf, u64 offset)
 
 	len = tmc_etr_buf_get_data(etr_buf, offset,
 				   CORESIGHT_BARRIER_PKT_SIZE, &bufp);
-	if (WARN_ON(len <= CORESIGHT_BARRIER_PKT_SIZE))
+	if (WARN_ON(len < CORESIGHT_BARRIER_PKT_SIZE))
 		return -EINVAL;
 	coresight_insert_barrier_packet(bufp);
 	return offset + CORESIGHT_BARRIER_PKT_SIZE;
-- 
2.7.4

[PATCH 17/25] coresight: Cleanup platform description data

[Mathieu Poirier]

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

Nobody uses the "clk" field in struct coresight_platform_data.
Remove it.

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>
---
 include/linux/coresight.h | 2 --
 1 file changed, 2 deletions(-)

diff --git a/include/linux/coresight.h b/include/linux/coresight.h
index e5421b83e4e6..69a5c9f82469 100644
--- a/include/linux/coresight.h
+++ b/include/linux/coresight.h
@@ -87,7 +87,6 @@ struct coresight_dev_subtype {
  * @child_ports:child component port number the current component is
 		connected  to.
  * @nr_outport:	number of output ports for this component.
- * @clk:	The clock this component is associated to.
  */
 struct coresight_platform_data {
 	int cpu;
@@ -97,7 +96,6 @@ struct coresight_platform_data {
 	const char **child_names;
 	int *child_ports;
 	int nr_outport;
-	struct clk *clk;
 };
 
 /**
-- 
2.7.4

[PATCH 18/25] coresight: Handle errors in finding input/output ports

[Mathieu Poirier]

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

If we fail to find the input / output port for a LINK component
while enabling a path, we should fail gracefully rather than
assuming port "0".

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 | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight.c b/drivers/hwtracing/coresight/coresight.c
index 4969b329511c..7f2b478a048f 100644
--- a/drivers/hwtracing/coresight/coresight.c
+++ b/drivers/hwtracing/coresight/coresight.c
@@ -107,7 +107,7 @@ static int coresight_find_link_inport(struct coresight_device *csdev,
 	dev_err(&csdev->dev, "couldn't find inport, parent: %s, child: %s\n",
 		dev_name(&parent->dev), dev_name(&csdev->dev));
 
-	return 0;
+	return -ENODEV;
 }
 
 static int coresight_find_link_outport(struct coresight_device *csdev,
@@ -125,7 +125,7 @@ static int coresight_find_link_outport(struct coresight_device *csdev,
 	dev_err(&csdev->dev, "couldn't find outport, parent: %s, child: %s\n",
 		dev_name(&csdev->dev), dev_name(&child->dev));
 
-	return 0;
+	return -ENODEV;
 }
 
 static int coresight_enable_sink(struct coresight_device *csdev, u32 mode)
@@ -178,6 +178,9 @@ static int coresight_enable_link(struct coresight_device *csdev,
 	else
 		refport = 0;
 
+	if (refport < 0)
+		return refport;
+
 	if (atomic_inc_return(&csdev->refcnt[refport]) == 1) {
 		if (link_ops(csdev)->enable) {
 			ret = link_ops(csdev)->enable(csdev, inport, outport);
-- 
2.7.4

[PATCH 19/25] coresight: Cleanup device subtype struct

[Mathieu Poirier]

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

Clean up our struct a little bit by using a union instead of
a struct for tracking the subtype of a 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>
---
 include/linux/coresight.h | 21 ++++++++++++---------
 1 file changed, 12 insertions(+), 9 deletions(-)

diff --git a/include/linux/coresight.h b/include/linux/coresight.h
index 69a5c9f82469..7c188c2a5b3c 100644
--- a/include/linux/coresight.h
+++ b/include/linux/coresight.h
@@ -63,17 +63,20 @@ enum coresight_dev_subtype_source {
 };
 
 /**
- * struct coresight_dev_subtype - further characterisation of a type
+ * union coresight_dev_subtype - further characterisation of a type
  * @sink_subtype:	type of sink this component is, as defined
-			by @coresight_dev_subtype_sink.
+ *			by @coresight_dev_subtype_sink.
  * @link_subtype:	type of link this component is, as defined
-			by @coresight_dev_subtype_link.
+ *			by @coresight_dev_subtype_link.
  * @source_subtype:	type of source this component is, as defined
-			by @coresight_dev_subtype_source.
+ *			by @coresight_dev_subtype_source.
  */
-struct coresight_dev_subtype {
-	enum coresight_dev_subtype_sink sink_subtype;
-	enum coresight_dev_subtype_link link_subtype;
+union coresight_dev_subtype {
+	/* We have some devices which acts as LINK and SINK */
+	struct {
+		enum coresight_dev_subtype_sink sink_subtype;
+		enum coresight_dev_subtype_link link_subtype;
+	};
 	enum coresight_dev_subtype_source source_subtype;
 };
 
@@ -111,7 +114,7 @@ struct coresight_platform_data {
  */
 struct coresight_desc {
 	enum coresight_dev_type type;
-	struct coresight_dev_subtype subtype;
+	union coresight_dev_subtype subtype;
 	const struct coresight_ops *ops;
 	struct coresight_platform_data *pdata;
 	struct device *dev;
@@ -155,7 +158,7 @@ struct coresight_device {
 	int nr_inport;
 	int nr_outport;
 	enum coresight_dev_type type;
-	struct coresight_dev_subtype subtype;
+	union coresight_dev_subtype subtype;
 	const struct coresight_ops *ops;
 	struct device dev;
 	atomic_t *refcnt;
-- 
2.7.4

[PATCH 20/25] coresight: Add helper device type

[Mathieu Poirier]

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

Add a new coresight device type, which do not belong to any
of the existing types, i.e, source, sink, link etc. A helper
device could be connected to a coresight device, which could
augment the functionality of the coresight device.

This is intended to cover Coresight Address Translation Unit (CATU)
devices, which provide improved Scatter Gather mechanism for TMC
ETR. The idea is that the helper device could be controlled by
the driver of the device it is attached to (in this case ETR),
transparent to the generic coresight driver (and paths).

The operations include enable(), disable(), both of which could
accept a device specific "data" which the driving device and
the helper device could share. Since they don't appear in the
coresight "path" tracked by software, we have to ensure that
they are powered up/down whenever the master device is turned
on.

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 | 43 +++++++++++++++++++++++++++++++--
 include/linux/coresight.h               | 24 ++++++++++++++++++
 2 files changed, 65 insertions(+), 2 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight.c b/drivers/hwtracing/coresight/coresight.c
index 7f2b478a048f..3e07fd335f8c 100644
--- a/drivers/hwtracing/coresight/coresight.c
+++ b/drivers/hwtracing/coresight/coresight.c
@@ -425,6 +425,42 @@ struct coresight_device *coresight_get_enabled_sink(bool deactivate)
 	return dev ? to_coresight_device(dev) : NULL;
 }
 
+/*
+ * coresight_grab_device - Power up this device and any of the helper
+ * devices connected to it for trace operation. Since the helper devices
+ * don't appear on the trace path, they should be handled along with the
+ * the master device.
+ */
+static void coresight_grab_device(struct coresight_device *csdev)
+{
+	int i;
+
+	for (i = 0; i < csdev->nr_outport; i++) {
+		struct coresight_device *child = csdev->conns[i].child_dev;
+
+		if (child && child->type == CORESIGHT_DEV_TYPE_HELPER)
+			pm_runtime_get_sync(child->dev.parent);
+	}
+	pm_runtime_get_sync(csdev->dev.parent);
+}
+
+/*
+ * coresight_drop_device - Release this device and any of the helper
+ * devices connected to it.
+ */
+static void coresight_drop_device(struct coresight_device *csdev)
+{
+	int i;
+
+	pm_runtime_put(csdev->dev.parent);
+	for (i = 0; i < csdev->nr_outport; i++) {
+		struct coresight_device *child = csdev->conns[i].child_dev;
+
+		if (child && child->type == CORESIGHT_DEV_TYPE_HELPER)
+			pm_runtime_put(child->dev.parent);
+	}
+}
+
 /**
  * _coresight_build_path - recursively build a path from a @csdev to a sink.
  * @csdev:	The device to start from.
@@ -473,9 +509,9 @@ static int _coresight_build_path(struct coresight_device *csdev,
 	if (!node)
 		return -ENOMEM;
 
+	coresight_grab_device(csdev);
 	node->csdev = csdev;
 	list_add(&node->link, path);
-	pm_runtime_get_sync(csdev->dev.parent);
 
 	return 0;
 }
@@ -519,7 +555,7 @@ void coresight_release_path(struct list_head *path)
 	list_for_each_entry_safe(nd, next, path, link) {
 		csdev = nd->csdev;
 
-		pm_runtime_put_sync(csdev->dev.parent);
+		coresight_drop_device(csdev);
 		list_del(&nd->link);
 		kfree(nd);
 	}
@@ -770,6 +806,9 @@ static struct device_type coresight_dev_type[] = {
 		.name = "source",
 		.groups = coresight_source_groups,
 	},
+	{
+		.name = "helper",
+	},
 };
 
 static void coresight_device_release(struct device *dev)
diff --git a/include/linux/coresight.h b/include/linux/coresight.h
index 7c188c2a5b3c..3d40a2b135f1 100644
--- a/include/linux/coresight.h
+++ b/include/linux/coresight.h
@@ -40,6 +40,7 @@ enum coresight_dev_type {
 	CORESIGHT_DEV_TYPE_LINK,
 	CORESIGHT_DEV_TYPE_LINKSINK,
 	CORESIGHT_DEV_TYPE_SOURCE,
+	CORESIGHT_DEV_TYPE_HELPER,
 };
 
 enum coresight_dev_subtype_sink {
@@ -62,6 +63,10 @@ enum coresight_dev_subtype_source {
 	CORESIGHT_DEV_SUBTYPE_SOURCE_SOFTWARE,
 };
 
+enum coresight_dev_subtype_helper {
+	CORESIGHT_DEV_SUBTYPE_HELPER_NONE,
+};
+
 /**
  * union coresight_dev_subtype - further characterisation of a type
  * @sink_subtype:	type of sink this component is, as defined
@@ -70,6 +75,8 @@ enum coresight_dev_subtype_source {
  *			by @coresight_dev_subtype_link.
  * @source_subtype:	type of source this component is, as defined
  *			by @coresight_dev_subtype_source.
+ * @helper_subtype:	type of helper this component is, as defined
+ *			by @coresight_dev_subtype_helper.
  */
 union coresight_dev_subtype {
 	/* We have some devices which acts as LINK and SINK */
@@ -78,6 +85,7 @@ union coresight_dev_subtype {
 		enum coresight_dev_subtype_link link_subtype;
 	};
 	enum coresight_dev_subtype_source source_subtype;
+	enum coresight_dev_subtype_helper helper_subtype;
 };
 
 /**
@@ -172,6 +180,7 @@ struct coresight_device {
 #define source_ops(csdev)	csdev->ops->source_ops
 #define sink_ops(csdev)		csdev->ops->sink_ops
 #define link_ops(csdev)		csdev->ops->link_ops
+#define helper_ops(csdev)	csdev->ops->helper_ops
 
 /**
  * struct coresight_ops_sink - basic operations for a sink
@@ -231,10 +240,25 @@ struct coresight_ops_source {
 			struct perf_event *event);
 };
 
+/**
+ * struct coresight_ops_helper - Operations for a helper device.
+ *
+ * All operations could pass in a device specific data, which could
+ * help the helper device to determine what to do.
+ *
+ * @enable	: Enable the device
+ * @disable	: Disable the device
+ */
+struct coresight_ops_helper {
+	int (*enable)(struct coresight_device *csdev, void *data);
+	int (*disable)(struct coresight_device *csdev, void *data);
+};
+
 struct coresight_ops {
 	const struct coresight_ops_sink *sink_ops;
 	const struct coresight_ops_link *link_ops;
 	const struct coresight_ops_source *source_ops;
+	const struct coresight_ops_helper *helper_ops;
 };
 
 #ifdef CONFIG_CORESIGHT
-- 
2.7.4

[PATCH 21/25] coresight: Introduce support for Coresight Address Translation Unit

[Mathieu Poirier]

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

Add the initial support for Coresight Address Translation Unit, which
augments the TMC in Coresight SoC-600 by providing an improved Scatter
Gather mechanism. CATU is always connected to a single TMC-ETR and
converts the AXI address with a translated address (from a given SG
table with specific format). The CATU should be programmed in pass
through mode and enabled even if the ETR doesn't use the translation
by CATU.

This patch provides mechanism to enable/disable the CATU always in the
pass through mode.

We reuse the existing ports mechanism to link the TMC-ETR to the
connected CATU.

i.e, TMC-ETR:output_port0 -> CATU:input_port0

Reference manual for CATU component is avilable in version r2p0 of :
"Arm Coresight System-on-Chip SoC-600 Technical Reference Manual".

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
 drivers/hwtracing/coresight/Kconfig             |  11 ++
 drivers/hwtracing/coresight/Makefile            |   1 +
 drivers/hwtracing/coresight/coresight-catu.c    | 214 ++++++++++++++++++++++++
 drivers/hwtracing/coresight/coresight-catu.h    |  84 ++++++++++
 drivers/hwtracing/coresight/coresight-tmc-etr.c |  52 ++++++
 include/linux/coresight.h                       |   1 +
 6 files changed, 363 insertions(+)
 create mode 100644 drivers/hwtracing/coresight/coresight-catu.c
 create mode 100644 drivers/hwtracing/coresight/coresight-catu.h

diff --git a/drivers/hwtracing/coresight/Kconfig b/drivers/hwtracing/coresight/Kconfig
index ef9cb3c164e1..ad34380cac49 100644
--- a/drivers/hwtracing/coresight/Kconfig
+++ b/drivers/hwtracing/coresight/Kconfig
@@ -31,6 +31,17 @@ config CORESIGHT_LINK_AND_SINK_TMC
 	  complies with the generic implementation of the component without
 	  special enhancement or added features.
 
+config CORESIGHT_CATU
+	bool "Coresight Address Translation Unit (CATU) driver"
+	depends on CORESIGHT_LINK_AND_SINK_TMC
+	help
+	   Enable support for the Coresight Address Translation Unit (CATU).
+	   CATU supports a scatter gather table of 4K pages, with forward/backward
+	   lookup. CATU helps TMC ETR to use a large physically non-contiguous trace
+	   buffer by translating the addresses used by ETR to the physical address
+	   by looking up the provided table. CATU can also be used in pass-through
+	   mode where the address is not translated.
+
 config CORESIGHT_SINK_TPIU
 	bool "Coresight generic TPIU driver"
 	depends on CORESIGHT_LINKS_AND_SINKS
diff --git a/drivers/hwtracing/coresight/Makefile b/drivers/hwtracing/coresight/Makefile
index 61db9dd0d571..41870ded51a3 100644
--- a/drivers/hwtracing/coresight/Makefile
+++ b/drivers/hwtracing/coresight/Makefile
@@ -18,3 +18,4 @@ obj-$(CONFIG_CORESIGHT_SOURCE_ETM4X) += coresight-etm4x.o \
 obj-$(CONFIG_CORESIGHT_DYNAMIC_REPLICATOR) += coresight-dynamic-replicator.o
 obj-$(CONFIG_CORESIGHT_STM) += coresight-stm.o
 obj-$(CONFIG_CORESIGHT_CPU_DEBUG) += coresight-cpu-debug.o
+obj-$(CONFIG_CORESIGHT_CATU) += coresight-catu.o
diff --git a/drivers/hwtracing/coresight/coresight-catu.c b/drivers/hwtracing/coresight/coresight-catu.c
new file mode 100644
index 000000000000..9d0cb1f6f16b
--- /dev/null
+++ b/drivers/hwtracing/coresight/coresight-catu.c
@@ -0,0 +1,214 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2018 Arm Limited. All rights reserved.
+ *
+ * Coresight Address Translation Unit support
+ *
+ * Author: Suzuki K Poulose <suzuki.poulose@arm.com>
+ */
+
+#include <linux/amba/bus.h>
+#include <linux/device.h>
+#include <linux/dma-mapping.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+
+#include "coresight-catu.h"
+#include "coresight-priv.h"
+
+#define csdev_to_catu_drvdata(csdev)	\
+	dev_get_drvdata(csdev->dev.parent)
+
+coresight_simple_reg32(struct catu_drvdata, devid, CORESIGHT_DEVID);
+coresight_simple_reg32(struct catu_drvdata, control, CATU_CONTROL);
+coresight_simple_reg32(struct catu_drvdata, status, CATU_STATUS);
+coresight_simple_reg32(struct catu_drvdata, mode, CATU_MODE);
+coresight_simple_reg32(struct catu_drvdata, axictrl, CATU_AXICTRL);
+coresight_simple_reg32(struct catu_drvdata, irqen, CATU_IRQEN);
+coresight_simple_reg64(struct catu_drvdata, sladdr,
+		       CATU_SLADDRLO, CATU_SLADDRHI);
+coresight_simple_reg64(struct catu_drvdata, inaddr,
+		       CATU_INADDRLO, CATU_INADDRHI);
+
+static struct attribute *catu_mgmt_attrs[] = {
+	&dev_attr_devid.attr,
+	&dev_attr_control.attr,
+	&dev_attr_status.attr,
+	&dev_attr_mode.attr,
+	&dev_attr_axictrl.attr,
+	&dev_attr_irqen.attr,
+	&dev_attr_sladdr.attr,
+	&dev_attr_inaddr.attr,
+	NULL,
+};
+
+static const struct attribute_group catu_mgmt_group = {
+	.attrs = catu_mgmt_attrs,
+	.name = "mgmt",
+};
+
+static const struct attribute_group *catu_groups[] = {
+	&catu_mgmt_group,
+	NULL,
+};
+
+
+static inline int catu_wait_for_ready(struct catu_drvdata *drvdata)
+{
+	return coresight_timeout(drvdata->base,
+				 CATU_STATUS, CATU_STATUS_READY, 1);
+}
+
+static int catu_enable_hw(struct catu_drvdata *drvdata, void *__unused)
+{
+	u32 control;
+
+	if (catu_wait_for_ready(drvdata))
+		dev_warn(drvdata->dev, "Timeout while waiting for READY\n");
+
+	control = catu_read_control(drvdata);
+	if (control & BIT(CATU_CONTROL_ENABLE)) {
+		dev_warn(drvdata->dev, "CATU is already enabled\n");
+		return -EBUSY;
+	}
+
+	control |= BIT(CATU_CONTROL_ENABLE);
+	catu_write_mode(drvdata, CATU_MODE_PASS_THROUGH);
+	catu_write_control(drvdata, control);
+	dev_dbg(drvdata->dev, "Enabled in Pass through mode\n");
+	return 0;
+}
+
+static int catu_enable(struct coresight_device *csdev, void *data)
+{
+	int rc;
+	struct catu_drvdata *catu_drvdata = csdev_to_catu_drvdata(csdev);
+
+	CS_UNLOCK(catu_drvdata->base);
+	rc = catu_enable_hw(catu_drvdata, data);
+	CS_LOCK(catu_drvdata->base);
+	return rc;
+}
+
+static int catu_disable_hw(struct catu_drvdata *drvdata)
+{
+	int rc = 0;
+
+	catu_write_control(drvdata, 0);
+	if (catu_wait_for_ready(drvdata)) {
+		dev_info(drvdata->dev, "Timeout while waiting for READY\n");
+		rc = -EAGAIN;
+	}
+
+	dev_dbg(drvdata->dev, "Disabled\n");
+	return rc;
+}
+
+static int catu_disable(struct coresight_device *csdev, void *__unused)
+{
+	int rc;
+	struct catu_drvdata *catu_drvdata = csdev_to_catu_drvdata(csdev);
+
+	CS_UNLOCK(catu_drvdata->base);
+	rc = catu_disable_hw(catu_drvdata);
+	CS_LOCK(catu_drvdata->base);
+	return rc;
+}
+
+const struct coresight_ops_helper catu_helper_ops = {
+	.enable = catu_enable,
+	.disable = catu_disable,
+};
+
+const struct coresight_ops catu_ops = {
+	.helper_ops = &catu_helper_ops,
+};
+
+static int catu_probe(struct amba_device *adev, const struct amba_id *id)
+{
+	int ret = 0;
+	u32 dma_mask;
+	struct catu_drvdata *drvdata;
+	struct coresight_desc catu_desc;
+	struct coresight_platform_data *pdata = NULL;
+	struct device *dev = &adev->dev;
+	struct device_node *np = dev->of_node;
+	void __iomem *base;
+
+	if (np) {
+		pdata = of_get_coresight_platform_data(dev, np);
+		if (IS_ERR(pdata)) {
+			ret = PTR_ERR(pdata);
+			goto out;
+		}
+		dev->platform_data = pdata;
+	}
+
+	drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
+	if (!drvdata) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	drvdata->dev = dev;
+	dev_set_drvdata(dev, drvdata);
+	base = devm_ioremap_resource(dev, &adev->res);
+	if (IS_ERR(base)) {
+		ret = PTR_ERR(base);
+		goto out;
+	}
+
+	/* Setup dma mask for the device */
+	dma_mask = readl_relaxed(base + CORESIGHT_DEVID) & 0x3f;
+	switch (dma_mask) {
+	case 32:
+	case 40:
+	case 44:
+	case 48:
+	case 52:
+	case 56:
+	case 64:
+		break;
+	default:
+		/* Default to the 40bits as supported by TMC-ETR */
+		dma_mask = 40;
+	}
+	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(dma_mask));
+	if (ret)
+		goto out;
+
+	drvdata->base = base;
+	catu_desc.pdata = pdata;
+	catu_desc.dev = dev;
+	catu_desc.groups = catu_groups;
+	catu_desc.type = CORESIGHT_DEV_TYPE_HELPER;
+	catu_desc.subtype.helper_subtype = CORESIGHT_DEV_SUBTYPE_HELPER_CATU;
+	catu_desc.ops = &catu_ops;
+	drvdata->csdev = coresight_register(&catu_desc);
+	if (IS_ERR(drvdata->csdev))
+		ret = PTR_ERR(drvdata->csdev);
+out:
+	pm_runtime_put(&adev->dev);
+	return ret;
+}
+
+static struct amba_id catu_ids[] = {
+	{
+		.id	= 0x000bb9ee,
+		.mask	= 0x000fffff,
+	},
+	{},
+};
+
+static struct amba_driver catu_driver = {
+	.drv = {
+		.name			= "coresight-catu",
+		.owner			= THIS_MODULE,
+		.suppress_bind_attrs	= true,
+	},
+	.probe				= catu_probe,
+	.id_table			= catu_ids,
+};
+
+builtin_amba_driver(catu_driver);
diff --git a/drivers/hwtracing/coresight/coresight-catu.h b/drivers/hwtracing/coresight/coresight-catu.h
new file mode 100644
index 000000000000..4f221fccffca
--- /dev/null
+++ b/drivers/hwtracing/coresight/coresight-catu.h
@@ -0,0 +1,84 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2018 Arm Limited. All rights reserved.
+ *
+ * Author: Suzuki K Poulose <suzuki.poulose@arm.com>
+ */
+
+#ifndef _CORESIGHT_CATU_H
+#define _CORESIGHT_CATU_H
+
+#include "coresight-priv.h"
+
+/* Register offset from base */
+#define CATU_CONTROL		0x000
+#define CATU_MODE		0x004
+#define CATU_AXICTRL		0x008
+#define CATU_IRQEN		0x00c
+#define CATU_SLADDRLO		0x020
+#define CATU_SLADDRHI		0x024
+#define CATU_INADDRLO		0x028
+#define CATU_INADDRHI		0x02c
+#define CATU_STATUS		0x100
+#define CATU_DEVARCH		0xfbc
+
+#define CATU_CONTROL_ENABLE	0
+
+#define CATU_MODE_PASS_THROUGH	0U
+#define CATU_MODE_TRANSLATE	1U
+
+#define CATU_STATUS_READY	8
+#define CATU_STATUS_ADRERR	0
+#define CATU_STATUS_AXIERR	4
+
+#define CATU_IRQEN_ON		0x1
+#define CATU_IRQEN_OFF		0x0
+
+struct catu_drvdata {
+	struct device *dev;
+	void __iomem *base;
+	struct coresight_device *csdev;
+	int irq;
+};
+
+#define CATU_REG32(name, offset)					\
+static inline u32							\
+catu_read_##name(struct catu_drvdata *drvdata)				\
+{									\
+	return coresight_read_reg_pair(drvdata->base, offset, -1);	\
+}									\
+static inline void							\
+catu_write_##name(struct catu_drvdata *drvdata, u32 val)		\
+{									\
+	coresight_write_reg_pair(drvdata->base, val, offset, -1);	\
+}
+
+#define CATU_REG_PAIR(name, lo_off, hi_off)				\
+static inline u64							\
+catu_read_##name(struct catu_drvdata *drvdata)				\
+{									\
+	return coresight_read_reg_pair(drvdata->base, lo_off, hi_off);	\
+}									\
+static inline void							\
+catu_write_##name(struct catu_drvdata *drvdata, u64 val)		\
+{									\
+	coresight_write_reg_pair(drvdata->base, val, lo_off, hi_off);	\
+}
+
+CATU_REG32(control, CATU_CONTROL);
+CATU_REG32(mode, CATU_MODE);
+CATU_REG_PAIR(sladdr, CATU_SLADDRLO, CATU_SLADDRHI)
+CATU_REG_PAIR(inaddr, CATU_INADDRLO, CATU_INADDRHI)
+
+static inline bool coresight_is_catu_device(struct coresight_device *csdev)
+{
+	if (!IS_ENABLED(CONFIG_CORESIGHT_CATU))
+		return false;
+	if (csdev->type != CORESIGHT_DEV_TYPE_HELPER)
+		return false;
+	if (csdev->subtype.helper_subtype != CORESIGHT_DEV_SUBTYPE_HELPER_CATU)
+		return false;
+	return true;
+}
+
+#endif
diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
index 8af451230121..e37923acb725 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
@@ -9,6 +9,7 @@
 #include <linux/iommu.h>
 #include <linux/slab.h>
 #include <linux/vmalloc.h>
+#include "coresight-catu.h"
 #include "coresight-priv.h"
 #include "coresight-tmc.h"
 
@@ -701,6 +702,48 @@ static const struct etr_buf_operations etr_sg_buf_ops = {
 	.get_data = tmc_etr_get_data_sg_buf,
 };
 
+/*
+ * TMC ETR could be connected to a CATU device, which can provide address
+ * translation service. This is represented by the Output port of the TMC
+ * (ETR) connected to the input port of the CATU.
+ *
+ * Returns	: coresight_device ptr for the CATU device if a CATU is found.
+ *		: NULL otherwise.
+ */
+static inline struct coresight_device *
+tmc_etr_get_catu_device(struct tmc_drvdata *drvdata)
+{
+	int i;
+	struct coresight_device *tmp, *etr = drvdata->csdev;
+
+	if (!IS_ENABLED(CONFIG_CORESIGHT_CATU))
+		return NULL;
+
+	for (i = 0; i < etr->nr_outport; i++) {
+		tmp = etr->conns[i].child_dev;
+		if (tmp && coresight_is_catu_device(tmp))
+			return tmp;
+	}
+
+	return NULL;
+}
+
+static inline void tmc_etr_enable_catu(struct tmc_drvdata *drvdata)
+{
+	struct coresight_device *catu = tmc_etr_get_catu_device(drvdata);
+
+	if (catu && helper_ops(catu)->enable)
+		helper_ops(catu)->enable(catu, NULL);
+}
+
+static inline void tmc_etr_disable_catu(struct tmc_drvdata *drvdata)
+{
+	struct coresight_device *catu = tmc_etr_get_catu_device(drvdata);
+
+	if (catu && helper_ops(catu)->disable)
+		helper_ops(catu)->disable(catu, NULL);
+}
+
 static const struct etr_buf_operations *etr_buf_ops[] = {
 	[ETR_MODE_FLAT] = &etr_flat_buf_ops,
 	[ETR_MODE_ETR_SG] = &etr_sg_buf_ops,
@@ -844,6 +887,12 @@ static void tmc_etr_enable_hw(struct tmc_drvdata *drvdata)
 	u32 axictl, sts;
 	struct etr_buf *etr_buf = drvdata->etr_buf;
 
+	/*
+	 * If this ETR is connected to a CATU, enable it before we turn
+	 * this on
+	 */
+	tmc_etr_enable_catu(drvdata);
+
 	CS_UNLOCK(drvdata->base);
 
 	/* Wait for TMCSReady bit to be set */
@@ -952,6 +1001,9 @@ static void tmc_etr_disable_hw(struct tmc_drvdata *drvdata)
 	tmc_disable_hw(drvdata);
 
 	CS_LOCK(drvdata->base);
+
+	/* Disable CATU device if this ETR is connected to one */
+	tmc_etr_disable_catu(drvdata);
 }
 
 static int tmc_enable_etr_sink_sysfs(struct coresight_device *csdev)
diff --git a/include/linux/coresight.h b/include/linux/coresight.h
index 3d40a2b135f1..d828a6efe0b1 100644
--- a/include/linux/coresight.h
+++ b/include/linux/coresight.h
@@ -65,6 +65,7 @@ enum coresight_dev_subtype_source {
 
 enum coresight_dev_subtype_helper {
 	CORESIGHT_DEV_SUBTYPE_HELPER_NONE,
+	CORESIGHT_DEV_SUBTYPE_HELPER_CATU,
 };
 
 /**
-- 
2.7.4

[PATCH 22/25] dts: bindings: Document device tree binding for CATU

[Mathieu Poirier]

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

Document CATU device-tree bindings. CATU augments the TMC-ETR
by providing an improved Scatter Gather mechanism for streaming
trace data to non-contiguous system RAM pages.

Cc: devicetree at vger.kernel.org
Cc: frowand.list at gmail.com
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
 .../devicetree/bindings/arm/coresight.txt          | 53 ++++++++++++++++++++++
 1 file changed, 53 insertions(+)

diff --git a/Documentation/devicetree/bindings/arm/coresight.txt b/Documentation/devicetree/bindings/arm/coresight.txt
index 9aa30a156b57..5d1ad09bafb4 100644
--- a/Documentation/devicetree/bindings/arm/coresight.txt
+++ b/Documentation/devicetree/bindings/arm/coresight.txt
@@ -39,6 +39,8 @@ its hardware characteristcs.
 
 		- System Trace Macrocell:
 			"arm,coresight-stm", "arm,primecell"; [1]
+		- Coresight Address Translation Unit (CATU)
+			"arm,coresight-catu", "arm,primecell";
 
 	* reg: physical base address and length of the register
 	  set(s) of the component.
@@ -90,6 +92,10 @@ its hardware characteristcs.
 	* arm,scatter-gather: boolean. Indicates that the TMC-ETR can safely
 	  use the SG mode on this system.
 
+* Optional property for CATU :
+	* interrupts : Exactly one SPI may be listed for reporting the address
+	  error
+
 Example:
 
 1. Sinks
@@ -121,6 +127,35 @@ Example:
 		};
 	};
 
+	etr at 20070000 {
+		compatible = "arm,coresight-tmc", "arm,primecell";
+		reg = <0 0x20070000 0 0x1000>;
+
+		clocks = <&oscclk6a>;
+		clock-names = "apb_pclk";
+		ports {
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			/* input port */
+			port at 0 {
+				reg =  <0>;
+				etr_in_port: endpoint {
+					slave-mode;
+					remote-endpoint = <&replicator2_out_port0>;
+				};
+			};
+
+			/* CATU link represented by output port */
+			port at 1 {
+				reg = <1>;
+				etr_out_port: endpoint {
+					remote-endpoint = <&catu_in_port>;
+				};
+			};
+		};
+	};
+
 2. Links
 	replicator {
 		/* non-configurable replicators don't show up on the
@@ -250,5 +285,23 @@ Example:
 		};
 	};
 
+5. CATU
+
+	catu at 207e0000 {
+		compatible = "arm,coresight-catu", "arm,primecell";
+		reg = <0 0x207e0000 0 0x1000>;
+
+		clocks = <&oscclk6a>;
+		clock-names = "apb_pclk";
+
+		interrupts = <GIC_SPI 4 IRQ_TYPE_LEVEL_HIGH>;
+		port {
+			catu_in_port: endpoint {
+				slave-mode;
+				remote-endpoint = <&etr_out_port>;
+			};
+		};
+	};
+
 [1]. There is currently two version of STM: STM32 and STM500.  Both
 have the same HW interface and as such don't need an explicit binding name.
-- 
2.7.4

[PATCH 23/25] coresight: catu: Add support for scatter gather tables

[Mathieu Poirier]

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

This patch adds the support for setting up a SG table for use
by the CATU. We reuse the tmc_sg_table to represent the table/data
pages, even though the table format is different.

Similar to ETR SG table, CATU uses a 4KB page size for data buffers
as well as page tables. All table entries are 64bit wide and have
the following format:

        63                      12      1  0
        x-----------------------------------x
        |        Address [63-12] | SBZ  | V |
        x-----------------------------------x

	Where [V] ->	 0 - Pointer is invalid
			 1 - Pointer is Valid

CATU uses only first half of the page for data page pointers.
i.e, single table page will only have 256 page pointers, addressing
upto 1MB of data. The second half of a table page contains only two
pointers at the end of the page (i.e, pointers at index 510 and 511),
which are used as links to the "Previous" and "Next" page tables
respectively.

The first table page has an "Invalid" previous pointer and the
next pointer entry points to the second page table if there is one.
Similarly the last table page has an "Invalid" next pointer to
indicate the end of the table chain.

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 | 251 +++++++++++++++++++++++++++
 1 file changed, 251 insertions(+)

diff --git a/drivers/hwtracing/coresight/coresight-catu.c b/drivers/hwtracing/coresight/coresight-catu.c
index 9d0cb1f6f16b..559d45b6bc39 100644
--- a/drivers/hwtracing/coresight/coresight-catu.c
+++ b/drivers/hwtracing/coresight/coresight-catu.c
@@ -16,10 +16,261 @@
 
 #include "coresight-catu.h"
 #include "coresight-priv.h"
+#include "coresight-tmc.h"
 
 #define csdev_to_catu_drvdata(csdev)	\
 	dev_get_drvdata(csdev->dev.parent)
 
+/* Verbose output for CATU table contents */
+#ifdef CATU_DEBUG
+#define catu_dbg(x, ...) dev_dbg(x, __VA_ARGS__)
+#else
+#define catu_dbg(x, ...) do {} while (0)
+#endif
+
+/*
+ * CATU uses a page size of 4KB for page tables as well as data pages.
+ * Each 64bit entry in the table has the following format.
+ *
+ *	63			12	1  0
+ *	------------------------------------
+ *	|	 Address [63-12] | SBZ	| V|
+ *	------------------------------------
+ *
+ * Where bit[0] V indicates if the address is valid or not.
+ * Each 4K table pages have upto 256 data page pointers, taking upto 2K
+ * size. There are two Link pointers, pointing to the previous and next
+ * table pages respectively at the end of the 4K page. (i.e, entry 510
+ * and 511).
+ *  E.g, a table of two pages could look like :
+ *
+ *                 Table Page 0               Table Page 1
+ * SLADDR ===> x------------------x  x--> x-----------------x
+ * INADDR    ->|  Page 0      | V |  |    | Page 256    | V | <- INADDR+1M
+ *             |------------------|  |    |-----------------|
+ * INADDR+4K ->|  Page 1      | V |  |    |                 |
+ *             |------------------|  |    |-----------------|
+ *             |  Page 2      | V |  |    |                 |
+ *             |------------------|  |    |-----------------|
+ *             |   ...        | V |  |    |    ...          |
+ *             |------------------|  |    |-----------------|
+ * INADDR+1020K|  Page 255    | V |  |    |   Page 511  | V |
+ * SLADDR+2K==>|------------------|  |    |-----------------|
+ *             |  UNUSED      |   |  |    |                 |
+ *             |------------------|  |    |                 |
+ *             |  UNUSED      |   |  |    |                 |
+ *             |------------------|  |    |                 |
+ *             |    ...       |   |  |    |                 |
+ *             |------------------|  |    |-----------------|
+ *             |   IGNORED    | 0 |  |    | Table Page 0| 1 |
+ *             |------------------|  |    |-----------------|
+ *             |  Table Page 1| 1 |--x    | IGNORED     | 0 |
+ *             x------------------x       x-----------------x
+ * SLADDR+4K==>
+ *
+ * The base input address (used by the ETR, programmed in INADDR_{LO,HI})
+ * must be aligned to 1MB (the size addressable by a single page table).
+ * The CATU maps INADDR{LO:HI} to the first page in the table pointed
+ * to by SLADDR{LO:HI} and so on.
+ *
+ */
+typedef u64 cate_t;
+
+#define CATU_PAGE_SHIFT		12
+#define CATU_PAGE_SIZE		(1UL << CATU_PAGE_SHIFT)
+#define CATU_PAGES_PER_SYSPAGE	(PAGE_SIZE / CATU_PAGE_SIZE)
+
+/* Page pointers are only allocated in the first 2K half */
+#define CATU_PTRS_PER_PAGE	((CATU_PAGE_SIZE >> 1) / sizeof(cate_t))
+#define CATU_PTRS_PER_SYSPAGE	(CATU_PAGES_PER_SYSPAGE * CATU_PTRS_PER_PAGE)
+#define CATU_LINK_PREV		((CATU_PAGE_SIZE / sizeof(cate_t)) - 2)
+#define CATU_LINK_NEXT		((CATU_PAGE_SIZE / sizeof(cate_t)) - 1)
+
+#define CATU_ADDR_SHIFT		12
+#define CATU_ADDR_MASK		~(((cate_t)1 << CATU_ADDR_SHIFT) - 1)
+#define CATU_ENTRY_VALID	((cate_t)0x1)
+#define CATU_VALID_ENTRY(addr) \
+	(((cate_t)(addr) & CATU_ADDR_MASK) | CATU_ENTRY_VALID)
+#define CATU_ENTRY_ADDR(entry)	((cate_t)(entry) & ~((cate_t)CATU_ENTRY_VALID))
+
+/*
+ * catu_get_table : Retrieve the table pointers for the given @offset
+ * within the buffer. The buffer is wrapped around to a valid offset.
+ *
+ * Returns : The CPU virtual address for the beginning of the table
+ * containing the data page pointer for @offset. If @daddrp is not NULL,
+ * @daddrp points the DMA address of the beginning of the table.
+ */
+static inline cate_t *catu_get_table(struct tmc_sg_table *catu_table,
+				     unsigned long offset,
+				     dma_addr_t *daddrp)
+{
+	unsigned long buf_size = tmc_sg_table_buf_size(catu_table);
+	unsigned int table_nr, pg_idx, pg_offset;
+	struct tmc_pages *table_pages = &catu_table->table_pages;
+	void *ptr;
+
+	/* Make sure offset is within the range */
+	offset %= buf_size;
+
+	/*
+	 * Each table can address 1MB and a single kernel page can
+	 * contain "CATU_PAGES_PER_SYSPAGE" CATU tables.
+	 */
+	table_nr = offset >> 20;
+	/* Find the table page where the table_nr lies in */
+	pg_idx = table_nr / CATU_PAGES_PER_SYSPAGE;
+	pg_offset = (table_nr % CATU_PAGES_PER_SYSPAGE) * CATU_PAGE_SIZE;
+	if (daddrp)
+		*daddrp = table_pages->daddrs[pg_idx] + pg_offset;
+	ptr = page_address(table_pages->pages[pg_idx]);
+	return (cate_t *)((unsigned long)ptr + pg_offset);
+}
+
+#ifdef CATU_DEBUG
+static void catu_dump_table(struct tmc_sg_table *catu_table)
+{
+	int i;
+	cate_t *table;
+	unsigned long table_end, buf_size, offset = 0;
+
+	buf_size = tmc_sg_table_buf_size(catu_table);
+	dev_dbg(catu_table->dev,
+		"Dump table %p, tdaddr: %llx\n",
+		catu_table, catu_table->table_daddr);
+
+	while (offset < buf_size) {
+		table_end = offset + SZ_1M < buf_size ?
+			    offset + SZ_1M : buf_size;
+		table = catu_get_table(catu_table, offset, NULL);
+		for (i = 0; offset < table_end; i++, offset += CATU_PAGE_SIZE)
+			dev_dbg(catu_table->dev, "%d: %llx\n", i, table[i]);
+		dev_dbg(catu_table->dev, "Prev : %llx, Next: %llx\n",
+			table[CATU_LINK_PREV], table[CATU_LINK_NEXT]);
+		dev_dbg(catu_table->dev, "== End of sub-table ===");
+	}
+	dev_dbg(catu_table->dev, "== End of Table ===");
+}
+
+#else
+static inline void catu_dump_table(struct tmc_sg_table *catu_table)
+{
+}
+#endif
+
+static inline cate_t catu_make_entry(dma_addr_t addr)
+{
+	return addr ? CATU_VALID_ENTRY(addr) : 0;
+}
+
+/*
+ * catu_populate_table : Populate the given CATU table.
+ * The table is always populated as a circular table.
+ * i.e, the "prev" link of the "first" table points to the "last"
+ * table and the "next" link of the "last" table points to the
+ * "first" table. The buffer should be made linear by calling
+ * catu_set_table().
+ */
+static void
+catu_populate_table(struct tmc_sg_table *catu_table)
+{
+	int i;
+	int sys_pidx;	/* Index to current system data page */
+	int catu_pidx;	/* Index of CATU page within the system data page */
+	unsigned long offset, buf_size, table_end;
+	dma_addr_t data_daddr;
+	dma_addr_t prev_taddr, next_taddr, cur_taddr;
+	cate_t *table_ptr, *next_table;
+
+	buf_size = tmc_sg_table_buf_size(catu_table);
+	sys_pidx = catu_pidx = 0;
+	offset = 0;
+
+	table_ptr = catu_get_table(catu_table, 0, &cur_taddr);
+	prev_taddr = 0;	/* Prev link for the first table */
+
+	while (offset < buf_size) {
+		/*
+		 * The @offset is always 1M aligned here and we have an
+		 * empty table @table_ptr to fill. Each table can address
+		 * upto 1MB data buffer. The last table may have fewer
+		 * entries if the buffer size is not aligned.
+		 */
+		table_end = (offset + SZ_1M) < buf_size ?
+			    (offset + SZ_1M) : buf_size;
+		for (i = 0; offset < table_end;
+		     i++, offset += CATU_PAGE_SIZE) {
+
+			data_daddr = catu_table->data_pages.daddrs[sys_pidx] +
+				     catu_pidx * CATU_PAGE_SIZE;
+			catu_dbg(catu_table->dev,
+				"[table %5ld:%03d] 0x%llx\n",
+				(offset >> 20), i, data_daddr);
+			table_ptr[i] = catu_make_entry(data_daddr);
+			/* Move the pointers for data pages */
+			catu_pidx = (catu_pidx + 1) % CATU_PAGES_PER_SYSPAGE;
+			if (catu_pidx == 0)
+				sys_pidx++;
+		}
+
+		/*
+		 * If we have finished all the valid entries, fill the rest of
+		 * the table (i.e, last table page) with invalid entries,
+		 * to fail the lookups.
+		 */
+		if (offset == buf_size) {
+			memset(&table_ptr[i], 0,
+			       sizeof(cate_t) * (CATU_PTRS_PER_PAGE - i));
+			next_taddr = 0;
+		} else {
+			next_table = catu_get_table(catu_table,
+						    offset, &next_taddr);
+		}
+
+		table_ptr[CATU_LINK_PREV] = catu_make_entry(prev_taddr);
+		table_ptr[CATU_LINK_NEXT] = catu_make_entry(next_taddr);
+
+		catu_dbg(catu_table->dev,
+			"[table%5ld]: Cur: 0x%llx Prev: 0x%llx, Next: 0x%llx\n",
+			(offset >> 20) - 1,  cur_taddr, prev_taddr, next_taddr);
+
+		/* Update the prev/next addresses */
+		if (next_taddr) {
+			prev_taddr = cur_taddr;
+			cur_taddr = next_taddr;
+			table_ptr = next_table;
+		}
+	}
+
+	/* Sync the table for device */
+	tmc_sg_table_sync_table(catu_table);
+}
+
+static struct tmc_sg_table __maybe_unused *
+catu_init_sg_table(struct device *catu_dev, int node,
+		   ssize_t size, void **pages)
+{
+	int nr_tpages;
+	struct tmc_sg_table *catu_table;
+
+	/*
+	 * Each table can address upto 1MB and we can have
+	 * CATU_PAGES_PER_SYSPAGE tables in a system page.
+	 */
+	nr_tpages = DIV_ROUND_UP(size, SZ_1M) / CATU_PAGES_PER_SYSPAGE;
+	catu_table = tmc_alloc_sg_table(catu_dev, node, nr_tpages,
+					size >> PAGE_SHIFT, pages);
+	if (IS_ERR(catu_table))
+		return catu_table;
+
+	catu_populate_table(catu_table);
+	dev_dbg(catu_dev,
+		"Setup table %p, size %ldKB, %d table pages\n",
+		catu_table, (unsigned long)size >> 10,  nr_tpages);
+	catu_dump_table(catu_table);
+	return catu_table;
+}
+
 coresight_simple_reg32(struct catu_drvdata, devid, CORESIGHT_DEVID);
 coresight_simple_reg32(struct catu_drvdata, control, CATU_CONTROL);
 coresight_simple_reg32(struct catu_drvdata, status, CATU_STATUS);
-- 
2.7.4

[PATCH 24/25] coresight: catu: Plug in CATU as a backend for ETR buffer

[Mathieu Poirier]

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

Now that we can use a CATU with a scatter gather table, add support
for the TMC ETR to make use of the connected CATU in translate mode.
This is done by adding CATU as new buffer mode.

Cc: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
 drivers/hwtracing/coresight/coresight-catu.c    | 122 +++++++++++++++++++++++-
 drivers/hwtracing/coresight/coresight-catu.h    |  35 +++++++
 drivers/hwtracing/coresight/coresight-tmc-etr.c |  25 +++--
 drivers/hwtracing/coresight/coresight-tmc.h     |   3 +
 4 files changed, 174 insertions(+), 11 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-catu.c b/drivers/hwtracing/coresight/coresight-catu.c
index 559d45b6bc39..ff94e58845b7 100644
--- a/drivers/hwtracing/coresight/coresight-catu.c
+++ b/drivers/hwtracing/coresight/coresight-catu.c
@@ -28,6 +28,11 @@
 #define catu_dbg(x, ...) do {} while (0)
 #endif
 
+struct catu_etr_buf {
+	struct tmc_sg_table *catu_table;
+	dma_addr_t sladdr;
+};
+
 /*
  * CATU uses a page size of 4KB for page tables as well as data pages.
  * Each 64bit entry in the table has the following format.
@@ -93,6 +98,9 @@ typedef u64 cate_t;
 	(((cate_t)(addr) & CATU_ADDR_MASK) | CATU_ENTRY_VALID)
 #define CATU_ENTRY_ADDR(entry)	((cate_t)(entry) & ~((cate_t)CATU_ENTRY_VALID))
 
+/* CATU expects the INADDR to be aligned to 1M. */
+#define CATU_DEFAULT_INADDR	(1ULL << 20)
+
 /*
  * catu_get_table : Retrieve the table pointers for the given @offset
  * within the buffer. The buffer is wrapped around to a valid offset.
@@ -246,7 +254,7 @@ catu_populate_table(struct tmc_sg_table *catu_table)
 	tmc_sg_table_sync_table(catu_table);
 }
 
-static struct tmc_sg_table __maybe_unused *
+static struct tmc_sg_table *
 catu_init_sg_table(struct device *catu_dev, int node,
 		   ssize_t size, void **pages)
 {
@@ -271,6 +279,91 @@ catu_init_sg_table(struct device *catu_dev, int node,
 	return catu_table;
 }
 
+static void catu_free_etr_buf(struct etr_buf *etr_buf)
+{
+	struct catu_etr_buf *catu_buf;
+
+	if (!etr_buf || etr_buf->mode != ETR_MODE_CATU || !etr_buf->private)
+		return;
+
+	catu_buf = etr_buf->private;
+	tmc_free_sg_table(catu_buf->catu_table);
+	kfree(catu_buf);
+}
+
+static ssize_t catu_get_data_etr_buf(struct etr_buf *etr_buf, u64 offset,
+				     size_t len, char **bufpp)
+{
+	struct catu_etr_buf *catu_buf = etr_buf->private;
+
+	return tmc_sg_table_get_data(catu_buf->catu_table, offset, len, bufpp);
+}
+
+static void catu_sync_etr_buf(struct etr_buf *etr_buf, u64 rrp, u64 rwp)
+{
+	struct catu_etr_buf *catu_buf = etr_buf->private;
+	struct tmc_sg_table *catu_table = catu_buf->catu_table;
+	u64 r_offset, w_offset;
+
+	/*
+	 * ETR started off at etr_buf->hwaddr. Convert the RRP/RWP to
+	 * offsets within the trace buffer.
+	 */
+	r_offset = rrp - etr_buf->hwaddr;
+	w_offset = rwp - etr_buf->hwaddr;
+
+	if (!etr_buf->full) {
+		etr_buf->len = w_offset - r_offset;
+		if (w_offset < r_offset)
+			etr_buf->len += etr_buf->size;
+	} else {
+		etr_buf->len = etr_buf->size;
+	}
+
+	etr_buf->offset = r_offset;
+	tmc_sg_table_sync_data_range(catu_table, r_offset, etr_buf->len);
+}
+
+static int catu_alloc_etr_buf(struct tmc_drvdata *tmc_drvdata,
+			      struct etr_buf *etr_buf, int node, void **pages)
+{
+	struct coresight_device *csdev;
+	struct device *catu_dev;
+	struct tmc_sg_table *catu_table;
+	struct catu_etr_buf *catu_buf;
+
+	csdev = tmc_etr_get_catu_device(tmc_drvdata);
+	if (!csdev)
+		return -ENODEV;
+	catu_dev = csdev->dev.parent;
+	catu_buf = kzalloc(sizeof(*catu_buf), GFP_KERNEL);
+	if (!catu_buf)
+		return -ENOMEM;
+
+	catu_table = catu_init_sg_table(catu_dev, node, etr_buf->size, pages);
+	if (IS_ERR(catu_table)) {
+		kfree(catu_buf);
+		return PTR_ERR(catu_table);
+	}
+
+	etr_buf->mode = ETR_MODE_CATU;
+	etr_buf->private = catu_buf;
+	etr_buf->hwaddr = CATU_DEFAULT_INADDR;
+
+	catu_buf->catu_table = catu_table;
+	/* Get the table base address */
+	catu_buf->sladdr = catu_table->table_daddr;
+
+	return 0;
+}
+
+const struct etr_buf_operations etr_catu_buf_ops = {
+	.alloc = catu_alloc_etr_buf,
+	.free = catu_free_etr_buf,
+	.sync = catu_sync_etr_buf,
+	.get_data = catu_get_data_etr_buf,
+};
+
 coresight_simple_reg32(struct catu_drvdata, devid, CORESIGHT_DEVID);
 coresight_simple_reg32(struct catu_drvdata, control, CATU_CONTROL);
 coresight_simple_reg32(struct catu_drvdata, status, CATU_STATUS);
@@ -311,9 +404,10 @@ static inline int catu_wait_for_ready(struct catu_drvdata *drvdata)
 				 CATU_STATUS, CATU_STATUS_READY, 1);
 }
 
-static int catu_enable_hw(struct catu_drvdata *drvdata, void *__unused)
+static int catu_enable_hw(struct catu_drvdata *drvdata, void *data)
 {
-	u32 control;
+	u32 control, mode;
+	struct etr_buf *etr_buf = data;
 
 	if (catu_wait_for_ready(drvdata))
 		dev_warn(drvdata->dev, "Timeout while waiting for READY\n");
@@ -325,9 +419,27 @@ static int catu_enable_hw(struct catu_drvdata *drvdata, void *__unused)
 	}
 
 	control |= BIT(CATU_CONTROL_ENABLE);
-	catu_write_mode(drvdata, CATU_MODE_PASS_THROUGH);
+
+	if (etr_buf && etr_buf->mode == ETR_MODE_CATU) {
+		struct catu_etr_buf *catu_buf = etr_buf->private;
+
+		mode = CATU_MODE_TRANSLATE;
+		catu_write_axictrl(drvdata, CATU_OS_AXICTRL);
+		catu_write_sladdr(drvdata, catu_buf->sladdr);
+		catu_write_inaddr(drvdata, CATU_DEFAULT_INADDR);
+	} else {
+		mode = CATU_MODE_PASS_THROUGH;
+		catu_write_sladdr(drvdata, 0);
+		catu_write_inaddr(drvdata, 0);
+	}
+
+	catu_write_irqen(drvdata, 0);
+	catu_write_mode(drvdata, mode);
 	catu_write_control(drvdata, control);
-	dev_dbg(drvdata->dev, "Enabled in Pass through mode\n");
+	dev_dbg(drvdata->dev, "Enabled in %s mode\n",
+		(mode == CATU_MODE_PASS_THROUGH) ?
+		"Pass through" :
+		"Translate");
 	return 0;
 }
 
diff --git a/drivers/hwtracing/coresight/coresight-catu.h b/drivers/hwtracing/coresight/coresight-catu.h
index 4f221fccffca..1b281f0dcccc 100644
--- a/drivers/hwtracing/coresight/coresight-catu.h
+++ b/drivers/hwtracing/coresight/coresight-catu.h
@@ -27,6 +27,32 @@
 #define CATU_MODE_PASS_THROUGH	0U
 #define CATU_MODE_TRANSLATE	1U
 
+#define CATU_AXICTRL_ARCACHE_SHIFT	4
+#define CATU_AXICTRL_ARCACHE_MASK	0xf
+#define CATU_AXICTRL_ARPROT_MASK	0x3
+#define CATU_AXICTRL_ARCACHE(arcache)		\
+	(((arcache) & CATU_AXICTRL_ARCACHE_MASK) << CATU_AXICTRL_ARCACHE_SHIFT)
+
+#define CATU_AXICTRL_VAL(arcache, arprot)	\
+	(CATU_AXICTRL_ARCACHE(arcache) | ((arprot) & CATU_AXICTRL_ARPROT_MASK))
+
+#define AXI3_AxCACHE_WB_READ_ALLOC	0x7
+/*
+ * AXI - ARPROT bits:
+ * See AMBA AXI & ACE Protocol specification (ARM IHI 0022E)
+ * sectionA4.7 Access Permissions.
+ *
+ * Bit 0: 0 - Unprivileged access, 1 - Privileged access
+ * Bit 1: 0 - Secure access, 1 - Non-secure access.
+ * Bit 2: 0 - Data access, 1 - instruction access.
+ *
+ * CATU AXICTRL:ARPROT[2] is res0 as we always access data.
+ */
+#define CATU_OS_ARPROT			0x2
+
+#define CATU_OS_AXICTRL		\
+	CATU_AXICTRL_VAL(AXI3_AxCACHE_WB_READ_ALLOC, CATU_OS_ARPROT)
+
 #define CATU_STATUS_READY	8
 #define CATU_STATUS_ADRERR	0
 #define CATU_STATUS_AXIERR	4
@@ -67,6 +93,8 @@ catu_write_##name(struct catu_drvdata *drvdata, u64 val)		\
 
 CATU_REG32(control, CATU_CONTROL);
 CATU_REG32(mode, CATU_MODE);
+CATU_REG32(irqen, CATU_IRQEN);
+CATU_REG32(axictrl, CATU_AXICTRL);
 CATU_REG_PAIR(sladdr, CATU_SLADDRLO, CATU_SLADDRHI)
 CATU_REG_PAIR(inaddr, CATU_INADDRLO, CATU_INADDRHI)
 
@@ -81,4 +109,11 @@ static inline bool coresight_is_catu_device(struct coresight_device *csdev)
 	return true;
 }
 
+#ifdef CONFIG_CORESIGHT_CATU
+extern const struct etr_buf_operations etr_catu_buf_ops;
+#else
+/* Dummy declaration for the CATU ops */
+static const struct etr_buf_operations etr_catu_buf_ops;
+#endif
+
 #endif
diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
index e37923acb725..2eda5de304c2 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
@@ -710,7 +710,7 @@ static const struct etr_buf_operations etr_sg_buf_ops = {
  * Returns	: coresight_device ptr for the CATU device if a CATU is found.
  *		: NULL otherwise.
  */
-static inline struct coresight_device *
+struct coresight_device *
 tmc_etr_get_catu_device(struct tmc_drvdata *drvdata)
 {
 	int i;
@@ -733,7 +733,7 @@ static inline void tmc_etr_enable_catu(struct tmc_drvdata *drvdata)
 	struct coresight_device *catu = tmc_etr_get_catu_device(drvdata);
 
 	if (catu && helper_ops(catu)->enable)
-		helper_ops(catu)->enable(catu, NULL);
+		helper_ops(catu)->enable(catu, drvdata->etr_buf);
 }
 
 static inline void tmc_etr_disable_catu(struct tmc_drvdata *drvdata)
@@ -741,12 +741,13 @@ static inline void tmc_etr_disable_catu(struct tmc_drvdata *drvdata)
 	struct coresight_device *catu = tmc_etr_get_catu_device(drvdata);
 
 	if (catu && helper_ops(catu)->disable)
-		helper_ops(catu)->disable(catu, NULL);
+		helper_ops(catu)->disable(catu, drvdata->etr_buf);
 }
 
 static const struct etr_buf_operations *etr_buf_ops[] = {
 	[ETR_MODE_FLAT] = &etr_flat_buf_ops,
 	[ETR_MODE_ETR_SG] = &etr_sg_buf_ops,
+	[ETR_MODE_CATU] = &etr_catu_buf_ops,
 };
 
 static inline int tmc_etr_mode_alloc_buf(int mode,
@@ -754,12 +755,15 @@ static inline int tmc_etr_mode_alloc_buf(int mode,
 					 struct etr_buf *etr_buf, int node,
 					 void **pages)
 {
-	int rc;
+	int rc = -EINVAL;
 
 	switch (mode) {
 	case ETR_MODE_FLAT:
 	case ETR_MODE_ETR_SG:
-		rc = etr_buf_ops[mode]->alloc(drvdata, etr_buf, node, pages);
+	case ETR_MODE_CATU:
+		if (etr_buf_ops[mode]->alloc)
+			rc = etr_buf_ops[mode]->alloc(drvdata, etr_buf,
+						      node, pages);
 		if (!rc)
 			etr_buf->ops = etr_buf_ops[mode];
 		return rc;
@@ -782,10 +786,14 @@ static struct etr_buf *tmc_alloc_etr_buf(struct tmc_drvdata *drvdata,
 {
 	int rc = -ENOMEM;
 	bool has_etr_sg, has_iommu;
+	bool has_sg, has_catu;
 	struct etr_buf *etr_buf;
 
 	has_etr_sg = tmc_etr_has_cap(drvdata, TMC_ETR_SG);
 	has_iommu = iommu_get_domain_for_dev(drvdata->dev);
+	has_catu = !!tmc_etr_get_catu_device(drvdata);
+
+	has_sg = has_catu || has_etr_sg;
 
 	etr_buf = kzalloc(sizeof(*etr_buf), GFP_KERNEL);
 	if (!etr_buf)
@@ -806,17 +814,22 @@ static struct etr_buf *tmc_alloc_etr_buf(struct tmc_drvdata *drvdata,
 	 *
 	 */
 	if (!pages &&
-	    (!has_etr_sg || has_iommu || size < SZ_1M))
+	    (!has_sg || has_iommu || size < SZ_1M))
 		rc = tmc_etr_mode_alloc_buf(ETR_MODE_FLAT, drvdata,
 					    etr_buf, node, pages);
 	if (rc && has_etr_sg)
 		rc = tmc_etr_mode_alloc_buf(ETR_MODE_ETR_SG, drvdata,
 					    etr_buf, node, pages);
+	if (rc && has_catu)
+		rc = tmc_etr_mode_alloc_buf(ETR_MODE_CATU, drvdata,
+					    etr_buf, node, pages);
 	if (rc) {
 		kfree(etr_buf);
 		return ERR_PTR(rc);
 	}
 
+	dev_dbg(drvdata->dev, "allocated buffer of size %ldKB in mode %d\n",
+		(unsigned long)size >> 10, etr_buf->mode);
 	return etr_buf;
 }
 
diff --git a/drivers/hwtracing/coresight/coresight-tmc.h b/drivers/hwtracing/coresight/coresight-tmc.h
index e7456575bfc1..7027bd60c4cc 100644
--- a/drivers/hwtracing/coresight/coresight-tmc.h
+++ b/drivers/hwtracing/coresight/coresight-tmc.h
@@ -126,6 +126,7 @@ enum tmc_mem_intf_width {
 enum etr_mode {
 	ETR_MODE_FLAT,		/* Uses contiguous flat buffer */
 	ETR_MODE_ETR_SG,	/* Uses in-built TMC ETR SG mechanism */
+	ETR_MODE_CATU,		/* Use SG mechanism in CATU */
 };
 
 struct etr_buf_operations;
@@ -303,4 +304,6 @@ tmc_sg_table_buf_size(struct tmc_sg_table *sg_table)
 	return sg_table->data_pages.nr_pages << PAGE_SHIFT;
 }
 
+struct coresight_device *tmc_etr_get_catu_device(struct tmc_drvdata *drvdata);
+
 #endif
-- 
2.7.4

[PATCH 25/25] coresight: tpiu: Fix disabling timeouts

[Mathieu Poirier]

From: Robin Murphy <robin.murphy@arm.com>

Probing the TPIU driver under UBSan triggers an out-of-bounds shift
warning in coresight_timeout():

...
[    5.677530] UBSAN: Undefined behaviour in drivers/hwtracing/coresight/coresight.c:929:16
[    5.685542] shift exponent 64 is too large for 64-bit type 'long unsigned int'
...

On closer inspection things are exponentially out of whack because we're
passing a bitmask where a bit number should be. Amusingly, it seems that
both calls will find their expected values by sheer luck and appear to
succeed: 1 << FFCR_FON_MAN ends up at bit 64 which whilst undefined
evaluates as zero in practice, while 1 << FFSR_FT_STOPPED finds bit 2
(TCPresent) which apparently is usually tied high.

Following the examples of other drivers, define separate FOO and FOO_BIT
macros for masks vs. indices, and put things right.

CC: Robert Walker <robert.walker@arm.com>
CC: Mike Leach <mike.leach@linaro.org>
CC: Mathieu Poirier <mathieu.poirier@linaro.org>
Fixes: 11595db8e17f ("coresight: Fix disabling of CoreSight TPIU")
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
---
 drivers/hwtracing/coresight/coresight-tpiu.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-tpiu.c b/drivers/hwtracing/coresight/coresight-tpiu.c
index 01b7457fe8fc..459ef930d98c 100644
--- a/drivers/hwtracing/coresight/coresight-tpiu.c
+++ b/drivers/hwtracing/coresight/coresight-tpiu.c
@@ -40,8 +40,9 @@
 
 /** register definition **/
 /* FFSR - 0x300 */
-#define FFSR_FT_STOPPED		BIT(1)
+#define FFSR_FT_STOPPED_BIT	1
 /* FFCR - 0x304 */
+#define FFCR_FON_MAN_BIT	6
 #define FFCR_FON_MAN		BIT(6)
 #define FFCR_STOP_FI		BIT(12)
 
@@ -86,9 +87,9 @@ static void tpiu_disable_hw(struct tpiu_drvdata *drvdata)
 	/* Generate manual flush */
 	writel_relaxed(FFCR_STOP_FI | FFCR_FON_MAN, drvdata->base + TPIU_FFCR);
 	/* Wait for flush to complete */
-	coresight_timeout(drvdata->base, TPIU_FFCR, FFCR_FON_MAN, 0);
+	coresight_timeout(drvdata->base, TPIU_FFCR, FFCR_FON_MAN_BIT, 0);
 	/* Wait for formatter to stop */
-	coresight_timeout(drvdata->base, TPIU_FFSR, FFSR_FT_STOPPED, 1);
+	coresight_timeout(drvdata->base, TPIU_FFSR, FFSR_FT_STOPPED_BIT, 1);
 
 	CS_LOCK(drvdata->base);
 }
-- 
2.7.4