coresight: cti: Add sysfs coresight mgmt register access

Adds sysfs access to the coresight management registers.
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/20200320165303.13681-3-mathieu.poirier@linaro.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

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

@@ -73,11 +73,64 @@ static struct attribute *coresight_cti_attrs[] = {
 	NULL,
 };
 
+/* register based attributes */
+
+/* macro to access RO registers with power check only (no enable check). */
+#define coresight_cti_reg(name, offset)			\
+static ssize_t name##_show(struct device *dev,				\
+			   struct device_attribute *attr, char *buf)	\
+{									\
+	struct cti_drvdata *drvdata = dev_get_drvdata(dev->parent);	\
+	u32 val = 0;							\
+	pm_runtime_get_sync(dev->parent);				\
+	spin_lock(&drvdata->spinlock);					\
+	if (drvdata->config.hw_powered)					\
+		val = readl_relaxed(drvdata->base + offset);		\
+	spin_unlock(&drvdata->spinlock);				\
+	pm_runtime_put_sync(dev->parent);				\
+	return sprintf(buf, "0x%x\n", val);				\
+}									\
+static DEVICE_ATTR_RO(name)
+
+/* coresight management registers */
+coresight_cti_reg(devaff0, CTIDEVAFF0);
+coresight_cti_reg(devaff1, CTIDEVAFF1);
+coresight_cti_reg(authstatus, CORESIGHT_AUTHSTATUS);
+coresight_cti_reg(devarch, CORESIGHT_DEVARCH);
+coresight_cti_reg(devid, CORESIGHT_DEVID);
+coresight_cti_reg(devtype, CORESIGHT_DEVTYPE);
+coresight_cti_reg(pidr0, CORESIGHT_PERIPHIDR0);
+coresight_cti_reg(pidr1, CORESIGHT_PERIPHIDR1);
+coresight_cti_reg(pidr2, CORESIGHT_PERIPHIDR2);
+coresight_cti_reg(pidr3, CORESIGHT_PERIPHIDR3);
+coresight_cti_reg(pidr4, CORESIGHT_PERIPHIDR4);
+
+static struct attribute *coresight_cti_mgmt_attrs[] = {
+	&dev_attr_devaff0.attr,
+	&dev_attr_devaff1.attr,
+	&dev_attr_authstatus.attr,
+	&dev_attr_devarch.attr,
+	&dev_attr_devid.attr,
+	&dev_attr_devtype.attr,
+	&dev_attr_pidr0.attr,
+	&dev_attr_pidr1.attr,
+	&dev_attr_pidr2.attr,
+	&dev_attr_pidr3.attr,
+	&dev_attr_pidr4.attr,
+	NULL,
+};
+
 static const struct attribute_group coresight_cti_group = {
 	.attrs = coresight_cti_attrs,
 };
 
+static const struct attribute_group coresight_cti_mgmt_group = {
+	.attrs = coresight_cti_mgmt_attrs,
+	.name = "mgmt",
+};
+
 const struct attribute_group *coresight_cti_groups[] = {
 	&coresight_cti_group,
+	&coresight_cti_mgmt_group,
 	NULL,
 };

drivers/hwtracing/coresight/coresight-priv.h

@@ -22,6 +22,7 @@
 #define CORESIGHT_CLAIMCLR	0xfa4
 #define CORESIGHT_LAR		0xfb0
 #define CORESIGHT_LSR		0xfb4
+#define CORESIGHT_DEVARCH	0xfbc
 #define CORESIGHT_AUTHSTATUS	0xfb8
 #define CORESIGHT_DEVID		0xfc8
 #define CORESIGHT_DEVTYPE	0xfcc