coresight: etm4x: Add missing API to set EL match on address filters

TRCACATRn registers have match bits for secure and non-secure exception
levels which are not accessible by the sysfs API.
This adds a new sysfs parameter to enable this - addr_exlevel_s_ns.
Signed-off-by: Mike Leach <mike.leach@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20191104181251.26732-7-mathieu.poirier@linaro.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/hwtracing/coresight/coresight-etm4x-sysfs.c

@@ -1233,6 +1233,47 @@ static ssize_t addr_context_store(struct device *dev,
 }
 static DEVICE_ATTR_RW(addr_context);
 
+static ssize_t addr_exlevel_s_ns_show(struct device *dev,
+				      struct device_attribute *attr,
+				      char *buf)
+{
+	u8 idx;
+	unsigned long val;
+	struct etmv4_drvdata *drvdata = dev_get_drvdata(dev->parent);
+	struct etmv4_config *config = &drvdata->config;
+
+	spin_lock(&drvdata->spinlock);
+	idx = config->addr_idx;
+	val = BMVAL(config->addr_acc[idx], 14, 8);
+	spin_unlock(&drvdata->spinlock);
+	return scnprintf(buf, PAGE_SIZE, "%#lx\n", val);
+}
+
+static ssize_t addr_exlevel_s_ns_store(struct device *dev,
+				       struct device_attribute *attr,
+				       const char *buf, size_t size)
+{
+	u8 idx;
+	unsigned long val;
+	struct etmv4_drvdata *drvdata = dev_get_drvdata(dev->parent);
+	struct etmv4_config *config = &drvdata->config;
+
+	if (kstrtoul(buf, 0, &val))
+		return -EINVAL;
+
+	if (val & ~((GENMASK(14, 8) >> 8)))
+		return -EINVAL;
+
+	spin_lock(&drvdata->spinlock);
+	idx = config->addr_idx;
+	/* clear Exlevel_ns & Exlevel_s bits[14:12, 11:8], bit[15] is res0 */
+	config->addr_acc[idx] &= ~(GENMASK(14, 8));
+	config->addr_acc[idx] |= (val << 8);
+	spin_unlock(&drvdata->spinlock);
+	return size;
+}
+static DEVICE_ATTR_RW(addr_exlevel_s_ns);
+
 static ssize_t seq_idx_show(struct device *dev,
 			    struct device_attribute *attr,
 			    char *buf)
@@ -2038,6 +2079,7 @@ static struct attribute *coresight_etmv4_attrs[] = {
 	&dev_attr_addr_stop.attr,
 	&dev_attr_addr_ctxtype.attr,
 	&dev_attr_addr_context.attr,
+	&dev_attr_addr_exlevel_s_ns.attr,
 	&dev_attr_seq_idx.attr,
 	&dev_attr_seq_state.attr,
 	&dev_attr_seq_event.attr,