[PATCH v2 6/9] coresight-tpdm: Add node to set dsb programming mode

[Tao Zhang <quic_taozha@xxxxxxxxxxx>]

Add node to set and show programming mode for TPDM DSB subunit.
Once the DSB programming mode is set, it will be written to the
register DSB_CR. Bit[10:9] of the DSB_CR register is used to set
the DSB test mode.

Signed-off-by: Tao Zhang <quic_taozha@xxxxxxxxxxx>
Signed-off-by: Tao Zhang <taozha@xxxxxxxxxxxxxxxx>
---
 drivers/hwtracing/coresight/coresight-tpdm.c | 45 +++++++++++++++++++++++++++-
 drivers/hwtracing/coresight/coresight-tpdm.h | 12 ++++++++
 2 files changed, 56 insertions(+), 1 deletion(-)

diff --git a/drivers/hwtracing/coresight/coresight-tpdm.c b/drivers/hwtracing/coresight/coresight-tpdm.c
index 1dbb6c4..9126a37 100644
--- a/drivers/hwtracing/coresight/coresight-tpdm.c
+++ b/drivers/hwtracing/coresight/coresight-tpdm.c
@@ -4,6 +4,7 @@
  */
 
 #include <linux/amba/bus.h>
+#include <linux/bitfield.h>
 #include <linux/bitmap.h>
 #include <linux/coresight.h>
 #include <linux/coresight-pmu.h>
@@ -38,7 +39,7 @@ static umode_t tpdm_dsb_is_visible(struct kobject *kobj,
 
 static void tpdm_enable_dsb(struct tpdm_drvdata *drvdata)
 {
-	u32 val;
+	u32 val, mode;
 
 	val = readl_relaxed(drvdata->base + TPDM_DSB_TIER);
 	/* Set trigger timestamp */
@@ -58,6 +59,19 @@ static void tpdm_enable_dsb(struct tpdm_drvdata *drvdata)
 
 	/* Set the enable bit of DSB control register to 1 */
 	val = readl_relaxed(drvdata->base + TPDM_DSB_CR);
+	/* Set the cycle accurate mode */
+	mode = TPDM_DSB_MODE_CYCACC(drvdata->dsb->mode);
+	val &= ~TPDM_DSB_TEST_MODE;
+	val |= FIELD_PREP(TPDM_DSB_TEST_MODE, mode);
+	/* Set the byte lane for high-performance mode */
+	mode = TPDM_DSB_MODE_HPBYTESEL(drvdata->dsb->mode);
+	val &= ~TPDM_DSB_HPSEL;
+	val |= FIELD_PREP(TPDM_DSB_HPSEL, mode);
+	/* Set the performance mode */
+	if (drvdata->dsb->mode & TPDM_DSB_MODE_PERF)
+		val |= TPDM_DSB_MODE;
+	else
+		val &= ~TPDM_DSB_MODE;
 	val |= TPDM_DSB_CR_ENA;
 	writel_relaxed(val, drvdata->base + TPDM_DSB_CR);
 }
@@ -257,6 +271,34 @@ static struct attribute_group tpdm_attr_grp = {
 	.attrs = tpdm_attrs,
 };
 
+static ssize_t dsb_mode_show(struct device *dev,
+				  struct device_attribute *attr,
+				  char *buf)
+{
+	struct tpdm_drvdata *drvdata = dev_get_drvdata(dev->parent);
+
+	return sysfs_emit(buf, "%lx\n",
+			 (unsigned long)drvdata->dsb->mode);
+}
+
+static ssize_t dsb_mode_store(struct device *dev,
+				   struct device_attribute *attr,
+				   const char *buf,
+				   size_t size)
+{
+	struct tpdm_drvdata *drvdata = dev_get_drvdata(dev->parent);
+	unsigned long val;
+
+	if ((kstrtoul(buf, 0, &val)) || val < 0)
+		return -EINVAL;
+
+	spin_lock(&drvdata->spinlock);
+	drvdata->dsb->mode = val & TPDM_MODE_ALL;
+	spin_unlock(&drvdata->spinlock);
+	return size;
+}
+static DEVICE_ATTR_RW(dsb_mode);
+
 static ssize_t dsb_trig_type_show(struct device *dev,
 				     struct device_attribute *attr,
 				     char *buf)
@@ -327,6 +369,7 @@ static ssize_t dsb_trig_ts_store(struct device *dev,
 }
 static DEVICE_ATTR_RW(dsb_trig_ts);
 static struct attribute *tpdm_dsb_attrs[] = {
+	&dev_attr_dsb_mode.attr,
 	&dev_attr_dsb_trig_ts.attr,
 	&dev_attr_dsb_trig_type.attr,
 	NULL,
diff --git a/drivers/hwtracing/coresight/coresight-tpdm.h b/drivers/hwtracing/coresight/coresight-tpdm.h
index 3ad1be5..b3ecb9f 100644
--- a/drivers/hwtracing/coresight/coresight-tpdm.h
+++ b/drivers/hwtracing/coresight/coresight-tpdm.h
@@ -19,6 +19,16 @@
 #define TPDM_DSB_XTRIG_TSENAB		BIT(1)
 /* Enable bit for DSB subunit trigger type */
 #define TPDM_DSB_TRIG_TYPE		BIT(12)
+/* Enable bit for DSB subunit perfmance mode */
+#define TPDM_DSB_MODE		BIT(1)
+
+/* DSB programming modes */
+#define TPDM_DSB_MODE_CYCACC(val)	(val & GENMASK(2, 0))
+#define TPDM_DSB_MODE_PERF		BIT(3)
+#define TPDM_DSB_MODE_HPBYTESEL(val)	(val & GENMASK(8, 4))
+#define TPDM_MODE_ALL			(0xFFFFFFF)
+#define TPDM_DSB_TEST_MODE		GENMASK(11, 9)
+#define TPDM_DSB_HPSEL		GENMASK(6, 2)
 
 /* TPDM integration test registers */
 #define TPDM_ITATBCNTRL		(0xEF0)
@@ -48,10 +58,12 @@
 
 /**
  * struct dsb_dataset - specifics associated to dsb dataset
+ * @mode:             DSB programming mode
  * @trig_ts:          Enable/Disable trigger timestamp.
  * @trig_type:        Enable/Disable trigger type.
  */
 struct dsb_dataset {
+	u32				mode;
 	bool			trig_ts;
 	bool			trig_type;
 };
-- 
2.7.4