[PATCH v2 1/5] perf: fsl_imx8_ddr: Add AXI ID PORT CHANNEL filter support

[Xu Yang]

This is the extension of AXI ID filter.

Filter is defined with 2 configuration registers per counter 1-3 (counter
0 is not used for filtering and lacks these registers).
* Counter N MASK COMP register - AXI_ID and AXI_MASKING.
* Counter N MUX CNTL register - AXI CHANNEL and AXI PORT.
  -- 0: address channel
  -- 1: data channel

This filter is exposed to userspace as an additional (channel, port) pair.
The definition of axi_channel is inverted in userspace, and it will be
reverted in driver automatically.

AXI filter of Perf Monitor in DDR Subsystem, only a single port0 exist, so
axi_port is reserved which should be 0.

e.g.
perf stat -a -e imx8_ddr0/axid-read,axi_mask=0xMMMM,axi_id=0xDDDD,axi_channel=0xH/ cmd
perf stat -a -e imx8_ddr0/axid-write,axi_mask=0xMMMM,axi_id=0xDDDD,axi_channel=0xH/ cmd

Signed-off-by: Xu Yang <xu.yang_2 at nxp.com>

---
Changes since v2:
 - no changes
---
 drivers/perf/fsl_imx8_ddr_perf.c | 39 ++++++++++++++++++++++++++++++++
 1 file changed, 39 insertions(+)

diff --git a/drivers/perf/fsl_imx8_ddr_perf.c b/drivers/perf/fsl_imx8_ddr_perf.c
index 92611c98120f..d0eae2d7e64b 100644
--- a/drivers/perf/fsl_imx8_ddr_perf.c
+++ b/drivers/perf/fsl_imx8_ddr_perf.c
@@ -19,6 +19,8 @@
 #define COUNTER_READ		0x20
 
 #define COUNTER_DPCR1		0x30
+#define COUNTER_MUX_CNTL	0x50
+#define COUNTER_MASK_COMP	0x54
 
 #define CNTL_OVER		0x1
 #define CNTL_CLEAR		0x2
@@ -32,6 +34,13 @@
 #define CNTL_CSV_SHIFT		24
 #define CNTL_CSV_MASK		(0xFFU << CNTL_CSV_SHIFT)
 
+#define READ_PORT_SHIFT		0
+#define READ_PORT_MASK		(0x7 << READ_PORT_SHIFT)
+#define READ_CHANNEL_REVERT	0x00000008	/* bit 3 for read channel select */
+#define WRITE_PORT_SHIFT	8
+#define WRITE_PORT_MASK		(0x7 << WRITE_PORT_SHIFT)
+#define WRITE_CHANNEL_REVERT	0x00000800	/* bit 11 for write channel select */
+
 #define EVENT_CYCLES_ID		0
 #define EVENT_CYCLES_COUNTER	0
 #define NUM_COUNTERS		4
@@ -50,6 +59,7 @@ static DEFINE_IDA(ddr_ida);
 /* DDR Perf hardware feature */
 #define DDR_CAP_AXI_ID_FILTER			0x1     /* support AXI ID filter */
 #define DDR_CAP_AXI_ID_FILTER_ENHANCED		0x3     /* support enhanced AXI ID filter */
+#define DDR_CAP_AXI_ID_PORT_CHANNEL_FILTER	0x4	/* support AXI ID PORT CHANNEL filter */
 
 struct fsl_ddr_devtype_data {
 	unsigned int quirks;    /* quirks needed for different DDR Perf core */
@@ -144,6 +154,7 @@ static const struct attribute_group ddr_perf_identifier_attr_group = {
 enum ddr_perf_filter_capabilities {
 	PERF_CAP_AXI_ID_FILTER = 0,
 	PERF_CAP_AXI_ID_FILTER_ENHANCED,
+	PERF_CAP_AXI_ID_PORT_CHANNEL_FILTER,
 	PERF_CAP_AXI_ID_FEAT_MAX,
 };
 
@@ -157,6 +168,8 @@ static u32 ddr_perf_filter_cap_get(struct ddr_pmu *pmu, int cap)
 	case PERF_CAP_AXI_ID_FILTER_ENHANCED:
 		quirks &= DDR_CAP_AXI_ID_FILTER_ENHANCED;
 		return quirks == DDR_CAP_AXI_ID_FILTER_ENHANCED;
+	case PERF_CAP_AXI_ID_PORT_CHANNEL_FILTER:
+		return !!(quirks & DDR_CAP_AXI_ID_PORT_CHANNEL_FILTER);
 	default:
 		WARN(1, "unknown filter cap %d\n", cap);
 	}
@@ -187,6 +200,7 @@ static ssize_t ddr_perf_filter_cap_show(struct device *dev,
 static struct attribute *ddr_perf_filter_cap_attr[] = {
 	PERF_FILTER_EXT_ATTR_ENTRY(filter, PERF_CAP_AXI_ID_FILTER),
 	PERF_FILTER_EXT_ATTR_ENTRY(enhanced_filter, PERF_CAP_AXI_ID_FILTER_ENHANCED),
+	PERF_FILTER_EXT_ATTR_ENTRY(super_filter, PERF_CAP_AXI_ID_PORT_CHANNEL_FILTER),
 	NULL,
 };
 
@@ -272,11 +286,15 @@ static const struct attribute_group ddr_perf_events_attr_group = {
 PMU_FORMAT_ATTR(event, "config:0-7");
 PMU_FORMAT_ATTR(axi_id, "config1:0-15");
 PMU_FORMAT_ATTR(axi_mask, "config1:16-31");
+PMU_FORMAT_ATTR(axi_port, "config2:0-2");
+PMU_FORMAT_ATTR(axi_channel, "config2:3-3");
 
 static struct attribute *ddr_perf_format_attrs[] = {
 	&format_attr_event.attr,
 	&format_attr_axi_id.attr,
 	&format_attr_axi_mask.attr,
+	&format_attr_axi_port.attr,
+	&format_attr_axi_channel.attr,
 	NULL,
 };
 
@@ -530,6 +548,7 @@ static int ddr_perf_event_add(struct perf_event *event, int flags)
 	int counter;
 	int cfg = event->attr.config;
 	int cfg1 = event->attr.config1;
+	int cfg2 = event->attr.config2;
 
 	if (pmu->devtype_data->quirks & DDR_CAP_AXI_ID_FILTER) {
 		int i;
@@ -553,6 +572,26 @@ static int ddr_perf_event_add(struct perf_event *event, int flags)
 		return -EOPNOTSUPP;
 	}
 
+	if (pmu->devtype_data->quirks & DDR_CAP_AXI_ID_PORT_CHANNEL_FILTER) {
+		if (ddr_perf_is_filtered(event)) {
+			/* revert axi id masking(axi_mask) value */
+			cfg1 ^= AXI_MASKING_REVERT;
+			writel(cfg1, pmu->base + COUNTER_MASK_COMP + ((counter - 1) << 4));
+
+			if (cfg == 0x41) {
+				/* revert axi read channel(axi_channel) value */
+				cfg2 ^= READ_CHANNEL_REVERT;
+				cfg2 |= FIELD_PREP(READ_PORT_MASK, cfg2);
+			} else {
+				/* revert axi write channel(axi_channel) value */
+				cfg2 ^= WRITE_CHANNEL_REVERT;
+				cfg2 |= FIELD_PREP(WRITE_PORT_MASK, cfg2);
+			}
+
+			writel(cfg2, pmu->base + COUNTER_MUX_CNTL + ((counter - 1) << 4));
+		}
+	}
+
 	pmu->events[counter] = event;
 	hwc->idx = counter;
 
-- 
2.34.1