Adds PCIE PMU support in Tegra410 SOC.

Signed-off-by: Besar Wicaksono <bwicaksono@nvidia.com>
---
 .../admin-guide/perf/nvidia-tegra410-pmu.rst  | 162 ++++++++++++++
 drivers/perf/arm_cspmu/nvidia_cspmu.c         | 208 +++++++++++++++++-
 2 files changed, 368 insertions(+), 2 deletions(-)

diff --git a/Documentation/admin-guide/perf/nvidia-tegra410-pmu.rst b/Documentation/admin-guide/perf/nvidia-tegra410-pmu.rst
index 7b7ba5700ca1..8528685ddb61 100644
--- a/Documentation/admin-guide/perf/nvidia-tegra410-pmu.rst
+++ b/Documentation/admin-guide/perf/nvidia-tegra410-pmu.rst
@@ -6,6 +6,7 @@ The NVIDIA Tegra410 SoC includes various system PMUs to measure key performance
 metrics like memory bandwidth, latency, and utilization:
 
 * Unified Coherence Fabric (UCF)
+* PCIE
 
 PMU Driver
 ----------
@@ -104,3 +105,164 @@ Example usage:
   destination filter = remote memory::
 
     perf stat -a -e nvidia_ucf_pmu_1/event=0x0,src_loc_noncpu=0x1,dst_rem=0x1/
+
+PCIE PMU
+--------
+
+This PMU monitors all read/write traffic from the root port(s) or a particular
+BDF in a PCIE root complex (RC) to local or remote memory. There is one PMU per
+PCIE RC in the SoC. Each RC can have up to 16 lanes that can be bifurcated into
+up to 8 root ports. The traffic from each root port can be filtered using RP or
+BDF filter. For example, specifying "src_rp_mask=0xFF" means the PMU counter will
+capture traffic from all RPs. Please see below for more details.
+
+The events and configuration options of this PMU device are described in sysfs,
+see /sys/bus/event_source/devices/nvidia_pcie_pmu_<socket-id>_rc_<pcie-rc-id>.
+
+The events in this PMU can be used to measure bandwidth, utilization, and
+latency:
+
+  * rd_req: count the number of read requests by PCIE device.
+  * wr_req: count the number of write requests by PCIE device.
+  * rd_bytes: count the number of bytes transferred by rd_req.
+  * wr_bytes: count the number of bytes transferred by wr_req.
+  * rd_cum_outs: count outstanding rd_req each cycle.
+  * cycles: counts the PCIE cycles.
+
+The average bandwidth is calculated as::
+
+   AVG_RD_BANDWIDTH_IN_GBPS = RD_BYTES / ELAPSED_TIME_IN_NS
+   AVG_WR_BANDWIDTH_IN_GBPS = WR_BYTES / ELAPSED_TIME_IN_NS
+
+The average request rate is calculated as::
+
+   AVG_RD_REQUEST_RATE = RD_REQ / CYCLES
+   AVG_WR_REQUEST_RATE = WR_REQ / CYCLES
+
+
+The average latency is calculated as::
+
+   FREQ_IN_GHZ = CYCLES / ELAPSED_TIME_IN_NS
+   AVG_LATENCY_IN_CYCLES = RD_CUM_OUTS / RD_REQ
+   AVERAGE_LATENCY_IN_NS = AVG_LATENCY_IN_CYCLES / FREQ_IN_GHZ
+
+The PMU events can be filtered based on the traffic source and destination.
+The source filter indicates the PCIE devices that will be monitored. The
+destination filter specifies the destination memory type, e.g. local system
+memory (CMEM), local GPU memory (GMEM), or remote memory. The local/remote
+classification of the destination filter is based on the home socket of the
+address, not where the data actually resides. These filters can be found in
+/sys/bus/event_source/devices/nvidia_pcie_pmu_<socket-id>_rc_<pcie-rc-id>/format/.
+
+The list of event filters:
+
+* Source filter:
+
+  * src_rp_mask: bitmask of root ports that will be monitored. Each bit in this
+    bitmask represents the RP index in the RC. If the bit is set, all devices under
+    the associated RP will be monitored. E.g "src_rp_mask=0xF" will monitor
+    devices in root port 0 to 3.
+  * src_bdf: the BDF that will be monitored. This is a 16-bit value that
+    follows formula: (bus << 8) + (device << 3) + (function). For example, the
+    value of BDF 27:01.1 is 0x2781.
+  * src_bdf_en: enable the BDF filter. If this is set, the BDF filter value in
+    "src_bdf" is used to filter the traffic.
+
+  Note that Root-Port and BDF filters are mutually exclusive and the PMU in
+  each RC can only have one BDF filter for the whole counters. If BDF filter
+  is enabled, the BDF filter value will be applied to all events.
+
+* Destination filter:
+
+  * dst_loc_cmem: if set, count events to local system memory (CMEM) address
+  * dst_loc_gmem: if set, count events to local GPU memory (GMEM) address
+  * dst_loc_pcie_p2p: if set, count events to local PCIE peer address
+  * dst_loc_pcie_cxl: if set, count events to local CXL memory address
+  * dst_rem: if set, count events to remote memory address
+
+If the source filter is not specified, the PMU will count events from all root
+ports. If the destination filter is not specified, the PMU will count events
+to all destinations.
+
+Example usage:
+
+* Count event id 0x0 from root port 0 of PCIE RC-0 on socket 0 targeting all
+  destinations::
+
+    perf stat -a -e nvidia_pcie_pmu_0_rc_0/event=0x0,src_rp_mask=0x1/
+
+* Count event id 0x1 from root port 0 and 1 of PCIE RC-1 on socket 0 and
+  targeting just local CMEM of socket 0::
+
+    perf stat -a -e nvidia_pcie_pmu_0_rc_1/event=0x1,src_rp_mask=0x3,dst_loc_cmem=0x1/
+
+* Count event id 0x2 from root port 0 of PCIE RC-2 on socket 1 targeting all
+  destinations::
+
+    perf stat -a -e nvidia_pcie_pmu_1_rc_2/event=0x2,src_rp_mask=0x1/
+
+* Count event id 0x3 from root port 0 and 1 of PCIE RC-3 on socket 1 and
+  targeting just local CMEM of socket 1::
+
+    perf stat -a -e nvidia_pcie_pmu_1_rc_3/event=0x3,src_rp_mask=0x3,dst_loc_cmem=0x1/
+
+* Count event id 0x4 from BDF 01:01.0 of PCIE RC-4 on socket 0 targeting all
+  destinations::
+
+    perf stat -a -e nvidia_pcie_pmu_0_rc_4/event=0x4,src_bdf=0x0180,src_bdf_en=0x1/
+
+Mapping the RC# to lspci segment number can be non-trivial; hence a new NVIDIA
+Designated Vendor Specific Capability (DVSEC) register is added into the PCIE config space
+for each RP. This DVSEC has vendor id "10de" and DVSEC id of "0x4". The DVSEC register
+contains the following information to map PCIE devices under the RP back to its RC# :
+
+  - Bus# (byte 0xc) : bus number as reported by the lspci output
+  - Segment# (byte 0xd) : segment number as reported by the lspci output
+  - RP# (byte 0xe) : port number as reported by LnkCap attribute from lspci for a device with Root Port capability
+  - RC# (byte 0xf): root complex number associated with the RP
+  - Socket# (byte 0x10): socket number associated with the RP
+
+Example script for mapping lspci BDF to RC# and socket#::
+
+  #!/bin/bash
+  while read bdf rest; do
+    dvsec4_reg=$(lspci -vv -s $bdf | awk '
+      /Designated Vendor-Specific: Vendor=10de ID=0004/ {
+        match($0, /\[([0-9a-fA-F]+)/, arr);
+        print "0x" arr[1];
+        exit
+      }
+    ')
+    if [ -n "$dvsec4_reg" ]; then
+      bus=$(setpci -s $bdf $(printf '0x%x' $((${dvsec4_reg} + 0xc))).b)
+      segment=$(setpci -s $bdf $(printf '0x%x' $((${dvsec4_reg} + 0xd))).b)
+      rp=$(setpci -s $bdf $(printf '0x%x' $((${dvsec4_reg} + 0xe))).b)
+      rc=$(setpci -s $bdf $(printf '0x%x' $((${dvsec4_reg} + 0xf))).b)
+      socket=$(setpci -s $bdf $(printf '0x%x' $((${dvsec4_reg} + 0x10))).b)
+      echo "$bdf: Bus=$bus, Segment=$segment, RP=$rp, RC=$rc, Socket=$socket"
+    fi
+  done < <(lspci -d 10de:)
+
+Example output::
+
+  0001:00:00.0: Bus=00, Segment=01, RP=00, RC=00, Socket=00
+  0002:80:00.0: Bus=80, Segment=02, RP=01, RC=01, Socket=00
+  0002:a0:00.0: Bus=a0, Segment=02, RP=02, RC=01, Socket=00
+  0002:c0:00.0: Bus=c0, Segment=02, RP=03, RC=01, Socket=00
+  0002:e0:00.0: Bus=e0, Segment=02, RP=04, RC=01, Socket=00
+  0003:00:00.0: Bus=00, Segment=03, RP=00, RC=02, Socket=00
+  0004:00:00.0: Bus=00, Segment=04, RP=00, RC=03, Socket=00
+  0005:00:00.0: Bus=00, Segment=05, RP=00, RC=04, Socket=00
+  0005:40:00.0: Bus=40, Segment=05, RP=01, RC=04, Socket=00
+  0005:c0:00.0: Bus=c0, Segment=05, RP=02, RC=04, Socket=00
+  0006:00:00.0: Bus=00, Segment=06, RP=00, RC=05, Socket=00
+  0009:00:00.0: Bus=00, Segment=09, RP=00, RC=00, Socket=01
+  000a:80:00.0: Bus=80, Segment=0a, RP=01, RC=01, Socket=01
+  000a:a0:00.0: Bus=a0, Segment=0a, RP=02, RC=01, Socket=01
+  000a:e0:00.0: Bus=e0, Segment=0a, RP=03, RC=01, Socket=01
+  000b:00:00.0: Bus=00, Segment=0b, RP=00, RC=02, Socket=01
+  000c:00:00.0: Bus=00, Segment=0c, RP=00, RC=03, Socket=01
+  000d:00:00.0: Bus=00, Segment=0d, RP=00, RC=04, Socket=01
+  000d:40:00.0: Bus=40, Segment=0d, RP=01, RC=04, Socket=01
+  000d:c0:00.0: Bus=c0, Segment=0d, RP=02, RC=04, Socket=01
+  000e:00:00.0: Bus=00, Segment=0e, RP=00, RC=05, Socket=01
diff --git a/drivers/perf/arm_cspmu/nvidia_cspmu.c b/drivers/perf/arm_cspmu/nvidia_cspmu.c
index c67667097a3c..3a5531d1f94c 100644
--- a/drivers/perf/arm_cspmu/nvidia_cspmu.c
+++ b/drivers/perf/arm_cspmu/nvidia_cspmu.c
@@ -8,6 +8,7 @@
 
 #include <linux/io.h>
 #include <linux/module.h>
+#include <linux/property.h>
 #include <linux/topology.h>
 
 #include "arm_cspmu.h"
@@ -28,6 +29,19 @@
 #define NV_UCF_FILTER_DST            GENMASK_ULL(11, 8)
 #define NV_UCF_FILTER_DEFAULT        (NV_UCF_FILTER_SRC | NV_UCF_FILTER_DST)
 
+#define NV_PCIE_V2_PORT_COUNT        8ULL
+#define NV_PCIE_V2_FILTER_ID_MASK    GENMASK_ULL(24, 0)
+#define NV_PCIE_V2_FILTER_PORT       GENMASK_ULL(NV_PCIE_V2_PORT_COUNT - 1, 0)
+#define NV_PCIE_V2_FILTER_BDF_VAL    GENMASK_ULL(23, NV_PCIE_V2_PORT_COUNT)
+#define NV_PCIE_V2_FILTER_BDF_EN     BIT(24)
+#define NV_PCIE_V2_FILTER_BDF_VAL_EN GENMASK_ULL(24, NV_PCIE_V2_PORT_COUNT)
+#define NV_PCIE_V2_FILTER_DEFAULT    NV_PCIE_V2_FILTER_PORT
+
+#define NV_PCIE_V2_DST_COUNT         5ULL
+#define NV_PCIE_V2_FILTER2_ID_MASK   GENMASK_ULL(4, 0)
+#define NV_PCIE_V2_FILTER2_DST       GENMASK_ULL(NV_PCIE_V2_DST_COUNT - 1, 0)
+#define NV_PCIE_V2_FILTER2_DEFAULT   NV_PCIE_V2_FILTER2_DST
+
 #define NV_GENERIC_FILTER_ID_MASK    GENMASK_ULL(31, 0)
 
 #define NV_PRODID_MASK	(PMIIDR_PRODUCTID | PMIIDR_VARIANT | PMIIDR_REVISION)
@@ -162,6 +176,16 @@ static struct attribute *ucf_pmu_event_attrs[] = {
 	NULL,
 };
 
+static struct attribute *pcie_v2_pmu_event_attrs[] = {
+	ARM_CSPMU_EVENT_ATTR(rd_bytes,		0x0),
+	ARM_CSPMU_EVENT_ATTR(wr_bytes,		0x1),
+	ARM_CSPMU_EVENT_ATTR(rd_req,		0x2),
+	ARM_CSPMU_EVENT_ATTR(wr_req,		0x3),
+	ARM_CSPMU_EVENT_ATTR(rd_cum_outs,	0x4),
+	ARM_CSPMU_EVENT_ATTR(cycles, ARM_CSPMU_EVT_CYCLES_DEFAULT),
+	NULL,
+};
+
 static struct attribute *generic_pmu_event_attrs[] = {
 	ARM_CSPMU_EVENT_ATTR(cycles, ARM_CSPMU_EVT_CYCLES_DEFAULT),
 	NULL,
@@ -202,6 +226,19 @@ static struct attribute *ucf_pmu_format_attrs[] = {
 	NULL,
 };
 
+static struct attribute *pcie_v2_pmu_format_attrs[] = {
+	ARM_CSPMU_FORMAT_EVENT_ATTR,
+	ARM_CSPMU_FORMAT_ATTR(src_rp_mask, "config1:0-7"),
+	ARM_CSPMU_FORMAT_ATTR(src_bdf, "config1:8-23"),
+	ARM_CSPMU_FORMAT_ATTR(src_bdf_en, "config1:24"),
+	ARM_CSPMU_FORMAT_ATTR(dst_loc_cmem, "config2:0"),
+	ARM_CSPMU_FORMAT_ATTR(dst_loc_gmem, "config2:1"),
+	ARM_CSPMU_FORMAT_ATTR(dst_loc_pcie_p2p, "config2:2"),
+	ARM_CSPMU_FORMAT_ATTR(dst_loc_pcie_cxl, "config2:3"),
+	ARM_CSPMU_FORMAT_ATTR(dst_rem, "config2:4"),
+	NULL,
+};
+
 static struct attribute *generic_pmu_format_attrs[] = {
 	ARM_CSPMU_FORMAT_EVENT_ATTR,
 	ARM_CSPMU_FORMAT_FILTER_ATTR,
@@ -233,6 +270,32 @@ nv_cspmu_get_name(const struct arm_cspmu *cspmu)
 	return ctx->name;
 }
 
+#if defined(CONFIG_ACPI)
+static int nv_cspmu_get_inst_id(const struct arm_cspmu *cspmu, u32 *id)
+{
+	struct fwnode_handle *fwnode;
+	struct acpi_device *adev;
+	int ret;
+
+	adev = arm_cspmu_acpi_dev_get(cspmu);
+	if (!adev)
+		return -ENODEV;
+
+	fwnode = acpi_fwnode_handle(adev);
+	ret = fwnode_property_read_u32(fwnode, "instance_id", id);
+	if (ret)
+		dev_err(cspmu->dev, "Failed to get instance ID\n");
+
+	acpi_dev_put(adev);
+	return ret;
+}
+#else
+static int nv_cspmu_get_inst_id(const struct arm_cspmu *cspmu, u32 *id)
+{
+	return -EINVAL;
+}
+#endif
+
 static u32 nv_cspmu_event_filter(const struct perf_event *event)
 {
 	const struct nv_cspmu_ctx *ctx =
@@ -278,6 +341,20 @@ static void nv_cspmu_set_ev_filter(struct arm_cspmu *cspmu,
 	}
 }
 
+static void nv_cspmu_reset_ev_filter(struct arm_cspmu *cspmu,
+				     const struct perf_event *event)
+{
+	const struct nv_cspmu_ctx *ctx =
+		to_nv_cspmu_ctx(to_arm_cspmu(event->pmu));
+	const u32 offset = 4 * event->hw.idx;
+
+	if (ctx->get_filter)
+		writel(0, cspmu->base0 + PMEVFILTR + offset);
+
+	if (ctx->get_filter2)
+		writel(0, cspmu->base0 + PMEVFILT2R + offset);
+}
+
 static void nv_cspmu_set_cc_filter(struct arm_cspmu *cspmu,
 				   const struct perf_event *event)
 {
@@ -308,9 +385,103 @@ static u32 ucf_pmu_event_filter(const struct perf_event *event)
 	return ret;
 }
 
+static u32 pcie_v2_pmu_bdf_val_en(u32 filter)
+{
+	const u32 bdf_en = FIELD_GET(NV_PCIE_V2_FILTER_BDF_EN, filter);
+
+	/* Returns both BDF value and enable bit if BDF filtering is enabled. */
+	if (bdf_en)
+		return FIELD_GET(NV_PCIE_V2_FILTER_BDF_VAL_EN, filter);
+
+	/* Ignore the BDF value if BDF filter is not enabled. */
+	return 0;
+}
+
+static u32 pcie_v2_pmu_event_filter(const struct perf_event *event)
+{
+	u32 filter, lead_filter, lead_bdf;
+	struct perf_event *leader;
+	const struct nv_cspmu_ctx *ctx =
+		to_nv_cspmu_ctx(to_arm_cspmu(event->pmu));
+
+	filter = event->attr.config1 & ctx->filter_mask;
+	if (filter != 0)
+		return filter;
+
+	leader = event->group_leader;
+
+	/* Use leader's filter value if its BDF filtering is enabled. */
+	if (event != leader) {
+		lead_filter = pcie_v2_pmu_event_filter(leader);
+		lead_bdf = pcie_v2_pmu_bdf_val_en(lead_filter);
+		if (lead_bdf != 0)
+			return lead_filter;
+	}
+
+	/* Otherwise, return default filter value. */
+	return ctx->filter_default_val;
+}
+
+static int pcie_v2_pmu_validate_event(struct arm_cspmu *cspmu,
+				   struct perf_event *new_ev)
+{
+	/*
+	 * Make sure the events are using same BDF filter since the PCIE-SRC PMU
+	 * only supports one common BDF filter setting for all of the counters.
+	 */
+
+	int idx;
+	u32 new_filter, new_rp, new_bdf, new_lead_filter, new_lead_bdf;
+	struct perf_event *leader, *new_leader;
+
+	if (cspmu->impl.ops.is_cycle_counter_event(new_ev))
+		return 0;
+
+	new_leader = new_ev->group_leader;
+
+	new_filter = pcie_v2_pmu_event_filter(new_ev);
+	new_lead_filter = pcie_v2_pmu_event_filter(new_leader);
+
+	new_bdf = pcie_v2_pmu_bdf_val_en(new_filter);
+	new_lead_bdf = pcie_v2_pmu_bdf_val_en(new_lead_filter);
+
+	new_rp = FIELD_GET(NV_PCIE_V2_FILTER_PORT, new_filter);
+
+	if (new_rp != 0 && new_bdf != 0) {
+		dev_err(cspmu->dev,
+			"RP and BDF filtering are mutually exclusive\n");
+		return -EINVAL;
+	}
+
+	if (new_bdf != new_lead_bdf) {
+		dev_err(cspmu->dev,
+			"sibling and leader BDF value should be equal\n");
+		return -EINVAL;
+	}
+
+	/* Compare BDF filter on existing events. */
+	idx = find_first_bit(cspmu->hw_events.used_ctrs,
+			     cspmu->cycle_counter_logical_idx);
+
+	if (idx != cspmu->cycle_counter_logical_idx) {
+		leader = cspmu->hw_events.events[idx]->group_leader;
+
+		const u32 lead_filter = pcie_v2_pmu_event_filter(leader);
+		const u32 lead_bdf = pcie_v2_pmu_bdf_val_en(lead_filter);
+
+		if (new_lead_bdf != lead_bdf) {
+			dev_err(cspmu->dev, "only one BDF value is supported\n");
+			return -EINVAL;
+		}
+	}
+
+	return 0;
+}
+
 enum nv_cspmu_name_fmt {
 	NAME_FMT_GENERIC,
-	NAME_FMT_SOCKET
+	NAME_FMT_SOCKET,
+	NAME_FMT_SOCKET_INST
 };
 
 struct nv_cspmu_match {
@@ -430,6 +601,27 @@ static const struct nv_cspmu_match nv_cspmu_match[] = {
 		.init_data = NULL
 	  },
 	},
+	{
+	  .prodid = 0x10301000,
+	  .prodid_mask = NV_PRODID_MASK,
+	  .name_pattern = "nvidia_pcie_pmu_%u_rc_%u",
+	  .name_fmt = NAME_FMT_SOCKET_INST,
+	  .template_ctx = {
+		.event_attr = pcie_v2_pmu_event_attrs,
+		.format_attr = pcie_v2_pmu_format_attrs,
+		.filter_mask = NV_PCIE_V2_FILTER_ID_MASK,
+		.filter_default_val = NV_PCIE_V2_FILTER_DEFAULT,
+		.filter2_mask = NV_PCIE_V2_FILTER2_ID_MASK,
+		.filter2_default_val = NV_PCIE_V2_FILTER2_DEFAULT,
+		.get_filter = pcie_v2_pmu_event_filter,
+		.get_filter2 = nv_cspmu_event_filter2,
+		.init_data = NULL
+	  },
+	  .ops = {
+		.validate_event = pcie_v2_pmu_validate_event,
+		.reset_ev_filter = nv_cspmu_reset_ev_filter,
+	  }
+	},
 	{
 	  .prodid = 0,
 	  .prodid_mask = 0,
@@ -453,7 +645,7 @@ static const struct nv_cspmu_match nv_cspmu_match[] = {
 static char *nv_cspmu_format_name(const struct arm_cspmu *cspmu,
 				  const struct nv_cspmu_match *match)
 {
-	char *name;
+	char *name = NULL;
 	struct device *dev = cspmu->dev;
 
 	static atomic_t pmu_generic_idx = {0};
@@ -467,6 +659,16 @@ static char *nv_cspmu_format_name(const struct arm_cspmu *cspmu,
 				       socket);
 		break;
 	}
+	case NAME_FMT_SOCKET_INST: {
+		const int cpu = cpumask_first(&cspmu->associated_cpus);
+		const int socket = cpu_to_node(cpu);
+		u32 inst_id;
+
+		if (!nv_cspmu_get_inst_id(cspmu, &inst_id))
+			name = devm_kasprintf(dev, GFP_KERNEL,
+					match->name_pattern, socket, inst_id);
+		break;
+	}
 	case NAME_FMT_GENERIC:
 		name = devm_kasprintf(dev, GFP_KERNEL, match->name_pattern,
 				       atomic_fetch_inc(&pmu_generic_idx));
@@ -514,8 +716,10 @@ static int nv_cspmu_init_ops(struct arm_cspmu *cspmu)
 	cspmu->impl.ctx = ctx;
 
 	/* NVIDIA specific callbacks. */
+	SET_OP(validate_event, impl_ops, match, NULL);
 	SET_OP(set_cc_filter, impl_ops, match, nv_cspmu_set_cc_filter);
 	SET_OP(set_ev_filter, impl_ops, match, nv_cspmu_set_ev_filter);
+	SET_OP(reset_ev_filter, impl_ops, match, NULL);
 	SET_OP(get_event_attrs, impl_ops, match, nv_cspmu_get_event_attrs);
 	SET_OP(get_format_attrs, impl_ops, match, nv_cspmu_get_format_attrs);
 	SET_OP(get_name, impl_ops, match, nv_cspmu_get_name);
-- 
2.43.0