[PATCH v3 07/11] coresight-tpdm: Add nodes for dsb edge control

[Tao Zhang]

Add the nodes to set value for DSB edge control and DSB edge
control mask. Each DSB subunit TPDM has maximum of n(n<16) EDCR
resgisters to configure edge control. DSB edge detection control
00: Rising edge detection
01: Falling edge detection
10: Rising and falling edge detection (toggle detection)
And each DSB subunit TPDM has maximum of m(m<8) ECDMR registers to
configure mask. Eight 32 bit registers providing DSB interface
edge detection mask control.

Signed-off-by: Tao Zhang <quic_taozha@xxxxxxxxxxx>
---
 .../ABI/testing/sysfs-bus-coresight-devices-tpdm   |  26 ++++
 drivers/hwtracing/coresight/coresight-tpdm.c       | 142 ++++++++++++++++++++-
 drivers/hwtracing/coresight/coresight-tpdm.h       |  14 ++
 3 files changed, 181 insertions(+), 1 deletion(-)

diff --git a/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm
index f13e282..094d624 100644
--- a/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm
+++ b/Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm
@@ -45,3 +45,29 @@ Description:
 		tpdm.
 
 		Accepts the value needs to be greater than 0.
+
+What:		/sys/bus/coresight/devices/<tpdm-name>/dsb_edge_ctrl
+Date:		March 2023
+KernelVersion	6.3
+Contact:	Jinlong Mao (QUIC) <quic_jinlmao@xxxxxxxxxxx>, Tao Zhang (QUIC) <quic_taozha@xxxxxxxxxxx>
+Description:
+		(Write) Set the edge control of DSB tpdm. Read the
+		edge control of DSB tpdm.
+
+		Accepts the following three values.
+		value 1: Start EDCR register number
+		value 2: End EDCR register number
+		value 3: The value need to be written
+
+What:		/sys/bus/coresight/devices/<tpdm-name>/dsb_edge_ctrl_mask
+Date:		March 2023
+KernelVersion	6.3
+Contact:	Jinlong Mao (QUIC) <quic_jinlmao@xxxxxxxxxxx>, Tao Zhang (QUIC) <quic_taozha@xxxxxxxxxxx>
+Description:
+		(Write) Set the edge control mask of DSB tpdm. Read
+		the edge control mask of DSB tpdm.
+
+		Accepts the following three values.
+		value 1: Start EDCMR register number
+		value 2: End EDCMR register number
+		value 3: The value need to be written
diff --git a/drivers/hwtracing/coresight/coresight-tpdm.c b/drivers/hwtracing/coresight/coresight-tpdm.c
index 8cd822f..2a0b36c 100644
--- a/drivers/hwtracing/coresight/coresight-tpdm.c
+++ b/drivers/hwtracing/coresight/coresight-tpdm.c
@@ -88,7 +88,14 @@ static void set_trigger_type(struct tpdm_drvdata *drvdata, u32 *val)
 
 static void tpdm_enable_dsb(struct tpdm_drvdata *drvdata)
 {
-	u32 val;
+	u32 val, i;
+
+	for (i = 0; i < TPDM_DSB_MAX_EDCR; i++)
+		writel_relaxed(drvdata->dsb->edge_ctrl[i],
+			   drvdata->base + TPDM_DSB_EDCR(i));
+	for (i = 0; i < TPDM_DSB_MAX_EDCMR; i++)
+		writel_relaxed(drvdata->dsb->edge_ctrl_mask[i],
+			   drvdata->base + TPDM_DSB_EDCMR(i));
 
 	val = readl_relaxed(drvdata->base + TPDM_DSB_TIER);
 	/* Set trigger timestamp */
@@ -311,6 +318,137 @@ static ssize_t dsb_mode_store(struct device *dev,
 }
 static DEVICE_ATTR_RW(dsb_mode);
 
+static ssize_t dsb_edge_ctrl_show(struct device *dev,
+				       struct device_attribute *attr,
+				       char *buf)
+{
+	struct tpdm_drvdata *drvdata = dev_get_drvdata(dev->parent);
+	ssize_t size = 0;
+	int i;
+
+	spin_lock(&drvdata->spinlock);
+	for (i = 0; i < TPDM_DSB_MAX_EDCR; i++) {
+		size += sysfs_emit_at(buf, size,
+				  "Index:0x%x Val:0x%x\n", i,
+				  drvdata->dsb->edge_ctrl[i]);
+	}
+	spin_unlock(&drvdata->spinlock);
+	return size;
+}
+
+/*
+ * value 1: Start EDCR register number
+ * value 2: End EDCR register number
+ * value 3: The value need to be written
+ * The EDCR registers can include up to 16 32-bit registers, and each
+ * one can be configured to control up to 16 edge detections(2 bits
+ * control one edge detection). So a total 256 edge detections can be
+ * configured. So the starting number(value 1) and ending number(value 2)
+ * cannot be greater than 256, and value 1 should be less than value 2.
+ * The following values are the rage of value 3.
+ * 0 - Rising edge detection
+ * 1 - Falling edge detection
+ * 2 - Rising and falling edge detection (toggle detection)
+ */
+static ssize_t dsb_edge_ctrl_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 start, end, edge_ctrl;
+	uint32_t val;
+	int i, index, bit, reg;
+
+	if (sscanf(buf, "%lx %lx %lx", &start, &end, &edge_ctrl) != 3)
+		return -EINVAL;
+	if ((start >= TPDM_DSB_MAX_LINES) || (end >= TPDM_DSB_MAX_LINES) ||
+	    edge_ctrl > 0x2)
+		return -EPERM;
+
+	spin_lock(&drvdata->spinlock);
+	for (i = start; i <= end; i++) {
+		/*
+		 * The 32-bit register has 32 bits(NUM_OF_BITS).
+		 * Each one register can be configured to control 16
+		 * (NUM_OF_BITS / 2) edge detectioins.
+		 */
+		reg = i / (NUM_OF_BITS / 2);
+		index = i % (NUM_OF_BITS / 2);
+		bit = index * 2;
+
+		val = drvdata->dsb->edge_ctrl[reg];
+		val &= ~GENMASK((bit + 1), bit);
+		val |= (edge_ctrl << bit);
+		drvdata->dsb->edge_ctrl[reg] = val;
+	}
+	spin_unlock(&drvdata->spinlock);
+
+	return size;
+}
+static DEVICE_ATTR_RW(dsb_edge_ctrl);
+
+static ssize_t dsb_edge_ctrl_mask_show(struct device *dev,
+					    struct device_attribute *attr,
+					    char *buf)
+{
+	struct tpdm_drvdata *drvdata = dev_get_drvdata(dev->parent);
+	ssize_t size = 0;
+	int i;
+
+	spin_lock(&drvdata->spinlock);
+	for (i = 0; i < TPDM_DSB_MAX_EDCR / 2; i++) {
+		size += sysfs_emit_at(buf, size,
+				  "Index:0x%x Val:0x%x\n", i,
+				  drvdata->dsb->edge_ctrl_mask[i]);
+	}
+	spin_unlock(&drvdata->spinlock);
+	return size;
+}
+
+/*
+ * value 1: Start EDCMR register number
+ * value 2: End EDCMR register number
+ * value 3: The value need to be written
+ */
+static ssize_t dsb_edge_ctrl_mask_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 start, end, val;
+	u32 set;
+	int i, index, reg;
+
+	if (sscanf(buf, "%lx %lx %lx", &start, &end, &val) != 3)
+		return -EINVAL;
+	if ((start >= TPDM_DSB_MAX_LINES) || (end >= TPDM_DSB_MAX_LINES)
+		|| (val & ~1UL))
+		return -EPERM;
+
+	spin_lock(&drvdata->spinlock);
+	for (i = start; i <= end; i++) {
+		/*
+		 * The 32-bit register has 32 bits(NUM_OF_BITS).
+		 * Each one register can be configured to control 32
+		 * (NUM_OF_BITS) edge detectioin masks.
+		 */
+		reg = i / NUM_OF_BITS;
+		index = (i % NUM_OF_BITS);
+
+		set = drvdata->dsb->edge_ctrl_mask[reg];
+		if (val)
+			set |= BIT(index);
+		else
+			set &= ~BIT(index);
+		drvdata->dsb->edge_ctrl_mask[reg] = set;
+	}
+	spin_unlock(&drvdata->spinlock);
+	return size;
+}
+static DEVICE_ATTR_RW(dsb_edge_ctrl_mask);
+
 static ssize_t dsb_trig_type_show(struct device *dev,
 				     struct device_attribute *attr,
 				     char *buf)
@@ -383,6 +521,8 @@ static DEVICE_ATTR_RW(dsb_trig_ts);
 
 static struct attribute *tpdm_dsb_attrs[] = {
 	&dev_attr_dsb_mode.attr,
+	&dev_attr_dsb_edge_ctrl.attr,
+	&dev_attr_dsb_edge_ctrl_mask.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 8fee562..342ef23 100644
--- a/drivers/hwtracing/coresight/coresight-tpdm.h
+++ b/drivers/hwtracing/coresight/coresight-tpdm.h
@@ -12,6 +12,8 @@
 /* DSB Subunit Registers */
 #define TPDM_DSB_CR		(0x780)
 #define TPDM_DSB_TIER		(0x784)
+#define TPDM_DSB_EDCR(n)	(0x808 + (n * 4))
+#define TPDM_DSB_EDCMR(n)	(0x848 + (n * 4))
 
 /* Enable bit for DSB subunit */
 #define TPDM_DSB_CR_ENA		BIT(0)
@@ -31,6 +33,8 @@
 #define TPDM_DSB_TEST_MODE		GENMASK(11, 9)
 #define TPDM_DSB_HPSEL		GENMASK(6, 2)
 
+#define NUM_OF_BITS		32
+
 /* TPDM integration test registers */
 #define TPDM_ITATBCNTRL		(0xEF0)
 #define TPDM_ITCNTRL		(0xF00)
@@ -57,14 +61,24 @@
 #define TPDM_PIDR0_DS_IMPDEF	BIT(0)
 #define TPDM_PIDR0_DS_DSB	BIT(1)
 
+#define TPDM_DSB_MAX_LINES	256
+/* MAX number of EDCR registers */
+#define TPDM_DSB_MAX_EDCR	16
+/* MAX number of EDCMR registers */
+#define TPDM_DSB_MAX_EDCMR	8
+
 /**
  * struct dsb_dataset - specifics associated to dsb dataset
  * @mode:             DSB programming mode
+ * @edge_ctrl:        Save value for edge control
+ * @edge_ctrl_mask:   Save value for edge control mask
  * @trig_ts:          Enable/Disable trigger timestamp.
  * @trig_type:        Enable/Disable trigger type.
  */
 struct dsb_dataset {
 	u32				mode;
+	u32				edge_ctrl[TPDM_DSB_MAX_EDCR];
+	u32				edge_ctrl_mask[TPDM_DSB_MAX_EDCMR];
 	bool			trig_ts;
 	bool			trig_type;
 };
-- 
2.7.4