[PATCH v4 04/13] coresight-etm4x: Controls pertaining to various configuration options

From: Mathieu Poirier
Date: Wed May 13 2015 - 12:38:56 EST


From: Pratik Patel <pratikp@xxxxxxxxxxxxxx>

Adding sysfs entries to configure:
. global timestamp.
. how often trace synchronisation occur.
. the threashold value for cycle counting.
. branch and broadcasting regions.

Signed-off-by: Pratik Patel <pratikp@xxxxxxxxxxxxxx>
Signed-off-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
---
.../ABI/testing/sysfs-bus-coresight-devices-etm4x | 26 +++++
drivers/hwtracing/coresight/coresight-etm4x.c | 124 +++++++++++++++++++++
2 files changed, 150 insertions(+)

diff --git a/Documentation/ABI/testing/sysfs-bus-coresight-devices-etm4x b/Documentation/ABI/testing/sysfs-bus-coresight-devices-etm4x
index 7917a180cfc6..7e5f9bf1d508 100644
--- a/Documentation/ABI/testing/sysfs-bus-coresight-devices-etm4x
+++ b/Documentation/ABI/testing/sysfs-bus-coresight-devices-etm4x
@@ -108,3 +108,29 @@ Date: April 2015
KernelVersion: 4.01
Contact: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
Description: (RW) Controls the behavior of the events in bank 0 to 3.
+
+What: /sys/bus/coresight/devices/<memory_map>.etm/event_ts
+Date: April 2015
+KernelVersion: 4.01
+Contact: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
+Description: (RW) Controls the insertion of global timestamps in the trace
+ streams.
+
+What: /sys/bus/coresight/devices/<memory_map>.etm/syncfreq
+Date: April 2015
+KernelVersion: 4.01
+Contact: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
+Description: (RW) Controls how often trace synchronization requests occur.
+
+What: /sys/bus/coresight/devices/<memory_map>.etm/cyc_threshold
+Date: April 2015
+KernelVersion: 4.01
+Contact: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
+Description: (RW) Sets the threshold value for cycle counting.
+
+What: /sys/bus/coresight/devices/<memory_map>.etm/bb_ctrl
+Date: April 2015
+KernelVersion: 4.01
+Contact: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
+Description: (RW) Controls which regions in the memory map are enabled to
+ use branch broadcasting.
diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c
index e9f58a5d2934..51fbda837026 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x.c
@@ -812,6 +812,126 @@ static ssize_t event_instren_store(struct device *dev,
}
static DEVICE_ATTR_RW(event_instren);

+static ssize_t event_ts_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ unsigned long val;
+ struct etmv4_drvdata *drvdata = dev_get_drvdata(dev->parent);
+
+ val = drvdata->ts_ctrl;
+ return scnprintf(buf, PAGE_SIZE, "%#lx\n", val);
+}
+
+static ssize_t event_ts_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ unsigned long val;
+ struct etmv4_drvdata *drvdata = dev_get_drvdata(dev->parent);
+
+ if (kstrtoul(buf, 16, &val))
+ return -EINVAL;
+ if (!drvdata->ts_size)
+ return -EINVAL;
+
+ drvdata->ts_ctrl = val & ETMv4_EVENT_MASK;
+ return size;
+}
+static DEVICE_ATTR_RW(event_ts);
+
+static ssize_t syncfreq_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ unsigned long val;
+ struct etmv4_drvdata *drvdata = dev_get_drvdata(dev->parent);
+
+ val = drvdata->syncfreq;
+ return scnprintf(buf, PAGE_SIZE, "%#lx\n", val);
+}
+
+static ssize_t syncfreq_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ unsigned long val;
+ struct etmv4_drvdata *drvdata = dev_get_drvdata(dev->parent);
+
+ if (kstrtoul(buf, 16, &val))
+ return -EINVAL;
+ if (drvdata->syncpr == true)
+ return -EINVAL;
+
+ drvdata->syncfreq = val & ETMv4_SYNC_MASK;
+ return size;
+}
+static DEVICE_ATTR_RW(syncfreq);
+
+static ssize_t cyc_threshold_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ unsigned long val;
+ struct etmv4_drvdata *drvdata = dev_get_drvdata(dev->parent);
+
+ val = drvdata->ccctlr;
+ return scnprintf(buf, PAGE_SIZE, "%#lx\n", val);
+}
+
+static ssize_t cyc_threshold_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ unsigned long val;
+ struct etmv4_drvdata *drvdata = dev_get_drvdata(dev->parent);
+
+ if (kstrtoul(buf, 16, &val))
+ return -EINVAL;
+ if (val < drvdata->ccitmin)
+ return -EINVAL;
+
+ drvdata->ccctlr = val & ETM_CYC_THRESHOLD_MASK;
+ return size;
+}
+static DEVICE_ATTR_RW(cyc_threshold);
+
+static ssize_t bb_ctrl_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ unsigned long val;
+ struct etmv4_drvdata *drvdata = dev_get_drvdata(dev->parent);
+
+ val = drvdata->bb_ctrl;
+ return scnprintf(buf, PAGE_SIZE, "%#lx\n", val);
+}
+
+static ssize_t bb_ctrl_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ unsigned long val;
+ struct etmv4_drvdata *drvdata = dev_get_drvdata(dev->parent);
+
+ if (kstrtoul(buf, 16, &val))
+ return -EINVAL;
+ if (drvdata->trcbb == false)
+ return -EINVAL;
+ if (!drvdata->nr_addr_cmp)
+ return -EINVAL;
+ /*
+ * Bit[7:0] selects which address range comparator is used for
+ * branch broadcast control.
+ */
+ if (BMVAL(val, 0, 7) > drvdata->nr_addr_cmp)
+ return -EINVAL;
+
+ drvdata->bb_ctrl = val;
+ return size;
+}
+static DEVICE_ATTR_RW(bb_ctrl);
+
static ssize_t cpu_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
@@ -839,6 +959,10 @@ static struct attribute *coresight_etmv4_attrs[] = {
&dev_attr_pe.attr,
&dev_attr_event.attr,
&dev_attr_event_instren.attr,
+ &dev_attr_event_ts.attr,
+ &dev_attr_syncfreq.attr,
+ &dev_attr_cyc_threshold.attr,
+ &dev_attr_bb_ctrl.attr,
&dev_attr_cpu.attr,
NULL,
};
--
1.9.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/