[PATCH v7 2/2] drivers/perf: hisi: Add driver for HiSilicon PCIe PMU

[Qi Liu <liuqi115@huawei.com>]

PCIe PMU Root Complex Integrated End Point(RCiEP) device is supported
to sample bandwidth, latency, buffer occupation etc.

Each PMU RCiEP device monitors multiple Root Ports, and each RCiEP is
registered as a PMU in /sys/bus/event_source/devices, so users can
select target PMU, and use filter to do further sets.

Filtering options contains:
event        - select the event.
subevent     - select the subevent.
port         - select target Root Ports. Information of Root Ports
               are shown under sysfs.
bdf          - select requester_id of target EP device.
trig_len     - set trigger condition for starting event statistics.
trigger_mode - set trigger mode. 0 means starting to statistic when
               bigger than trigger condition, and 1 means smaller.
thr_len      - set threshold for statistics.
thr_mode     - set threshold mode. 0 means count when bigger than
               threshold, and 1 means smaller.

Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Qi Liu <liuqi115@huawei.com>
---
 MAINTAINERS                            |   2 +
 drivers/perf/hisilicon/Kconfig         |   9 +
 drivers/perf/hisilicon/Makefile        |   2 +
 drivers/perf/hisilicon/hisi_pcie_pmu.c | 967 +++++++++++++++++++++++++++++++++
 include/linux/cpuhotplug.h             |   1 +
 5 files changed, 981 insertions(+)
 create mode 100644 drivers/perf/hisilicon/hisi_pcie_pmu.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 81e1ede..8639c1c 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8228,8 +8228,10 @@ F:	Documentation/devicetree/bindings/misc/hisilicon-hikey-usb.yaml
 
 HISILICON PMU DRIVER
 M:	Shaokun Zhang <zhangshaokun@hisilicon.com>
+M:	Qi Liu <liuqi115@huawei.com>
 S:	Supported
 W:	http://www.hisilicon.com
+F:	Documentation/admin-guide/perf/hisi-pcie-pmu.rst
 F:	Documentation/admin-guide/perf/hisi-pmu.rst
 F:	drivers/perf/hisilicon
 
diff --git a/drivers/perf/hisilicon/Kconfig b/drivers/perf/hisilicon/Kconfig
index c5d1b701..5546218 100644
--- a/drivers/perf/hisilicon/Kconfig
+++ b/drivers/perf/hisilicon/Kconfig
@@ -5,3 +5,12 @@ config HISI_PMU
 	  help
 	  Support for HiSilicon SoC L3 Cache performance monitor, Hydra Home
 	  Agent performance monitor and DDR Controller performance monitor.
+
+config HISI_PCIE_PMU
+	tristate "HiSilicon PCIE PERF PMU"
+	depends on PCI && ARM64
+	help
+	  Provide support for HiSilicon PCIe performance monitoring unit (PMU)
+	  RCiEP devices.
+	  Adds the PCIe PMU into perf events system for monitoring latency,
+	  bandwidth etc.
diff --git a/drivers/perf/hisilicon/Makefile b/drivers/perf/hisilicon/Makefile
index 7643c9f..506ed39 100644
--- a/drivers/perf/hisilicon/Makefile
+++ b/drivers/perf/hisilicon/Makefile
@@ -2,3 +2,5 @@
 obj-$(CONFIG_HISI_PMU) += hisi_uncore_pmu.o hisi_uncore_l3c_pmu.o \
 			  hisi_uncore_hha_pmu.o hisi_uncore_ddrc_pmu.o hisi_uncore_sllc_pmu.o \
 			  hisi_uncore_pa_pmu.o
+
+obj-$(CONFIG_HISI_PCIE_PMU) += hisi_pcie_pmu.o
diff --git a/drivers/perf/hisilicon/hisi_pcie_pmu.c b/drivers/perf/hisilicon/hisi_pcie_pmu.c
new file mode 100644
index 0000000..50994e5
--- /dev/null
+++ b/drivers/perf/hisilicon/hisi_pcie_pmu.c
@@ -0,0 +1,967 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * This driver adds support for PCIe PMU RCiEP device. Related
+ * perf events are bandwidth, bandwidth utilization, latency
+ * etc.
+ *
+ * Copyright (C) 2021 HiSilicon Limited
+ * Author: Qi Liu <liuqi115@huawei.com>
+ */
+#include <linux/bitfield.h>
+#include <linux/bitmap.h>
+#include <linux/bug.h>
+#include <linux/cpuhotplug.h>
+#include <linux/cpumask.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/perf_event.h>
+
+/* Define registers */
+#define HISI_PCIE_GLOBAL_CTRL		0x00
+#define HISI_PCIE_EVENT_CTRL		0x010
+#define HISI_PCIE_CNT			0x090
+#define HISI_PCIE_EXT_CNT		0x110
+#define HISI_PCIE_INT_STAT		0x150
+#define HISI_PCIE_INT_MASK		0x154
+#define HISI_PCIE_REG_BDF		0xfe0
+#define HISI_PCIE_REG_VERSION		0xfe4
+#define HISI_PCIE_REG_INFO		0xfe8
+
+/* Define PCIE CTRL CMD */
+#define HISI_PCIE_GLOBAL_EN		0x01
+#define HISI_PCIE_GLOBAL_NONE		0
+#define HISI_PCIE_EVENT_EN		BIT_ULL(20)
+#define HISI_PCIE_RESET_CNT		BIT_ULL(22)
+#define HISI_PCIE_DEFAULT_SET		BIT_ULL(34)
+#define HISI_PCIE_THR_EN		BIT_ULL(26)
+#define HISI_PCIE_TARGET_EN		BIT_ULL(32)
+#define HISI_PCIE_TRIG_EN		BIT_ULL(52)
+
+/* Define offsets in event ctrl regesiter */
+#define HISI_PCIE_EVENT_M		GENMASK_ULL(7, 0)
+#define HISI_PCIE_SUBEVENT_M		GENMASK_ULL(15, 8)
+#define HISI_PCIE_THR_MODE_M		GENMASK_ULL(27, 27)
+#define HISI_PCIE_THR_M			GENMASK_ULL(31, 28)
+#define HISI_PCIE_TARGET_M		GENMASK_ULL(52, 36)
+#define HISI_PCIE_TRIG_MODE_M		GENMASK_ULL(53, 53)
+#define HISI_PCIE_TRIG_M		GENMASK_ULL(59, 56)
+
+#define HISI_PCIE_MAX_COUNTERS		8
+#define HISI_PCIE_REG_STEP		8
+#define HISI_PCIE_EVENT_MAX		0xa2
+#define HISI_PCIE_SUBEVENT_MAX		0x20
+#define HISI_PCIE_THR_MAX_VAL		10
+#define HISI_PCIE_TRIG_MAX_VAL		10
+#define HISI_PCIE_MAX_PERIOD		(GENMASK_ULL(63, 0))
+#define HISI_PCIE_DEFAULT_VALUE		BIT_ULL(63)
+
+struct hisi_pcie_pmu {
+	struct perf_event *hw_events[HISI_PCIE_MAX_COUNTERS];
+	struct hlist_node node;
+	struct pci_dev *pdev;
+	struct pmu pmu;
+	void __iomem *base;
+	int irq;
+	u32 identifier;
+	/* Minimum and maximum bdf of root ports monitored by PMU */
+	u16 bdf_min;
+	u16 bdf_max;
+	int on_cpu;
+};
+
+struct hisi_pcie_reg_pair {
+	u16 lo;
+	u16 hi;
+};
+
+#define to_pcie_pmu(p)  (container_of((p), struct hisi_pcie_pmu, pmu))
+#define GET_PCI_DEVFN(bdf)  ((bdf) & 0xff)
+#define EXT_COUNTER_IS_USED(idx)		((idx) & GENMASK(15, 8))
+
+#define HISI_PCIE_PMU_FILTER_ATTR(_name, _config, _hi, _lo)		  \
+	static u64 hisi_pcie_get_##_name(struct perf_event *event)	  \
+	{								  \
+		return FIELD_GET(GENMASK(_hi, _lo), event->attr._config); \
+	}								  \
+
+HISI_PCIE_PMU_FILTER_ATTR(event, config, 15, 0);
+HISI_PCIE_PMU_FILTER_ATTR(subevent, config, 23, 16);
+HISI_PCIE_PMU_FILTER_ATTR(thr_len, config1, 3, 0);
+HISI_PCIE_PMU_FILTER_ATTR(thr_mode, config1, 4, 4);
+HISI_PCIE_PMU_FILTER_ATTR(trig_len, config1, 8, 5);
+HISI_PCIE_PMU_FILTER_ATTR(trig_mode, config1, 9, 9);
+HISI_PCIE_PMU_FILTER_ATTR(port, config2, 15, 0);
+HISI_PCIE_PMU_FILTER_ATTR(bdf, config2, 31, 16);
+
+static ssize_t hisi_pcie_format_sysfs_show(struct device *dev,
+				    struct device_attribute *attr, char *buf)
+{
+	struct dev_ext_attribute *eattr;
+
+	eattr = container_of(attr, struct dev_ext_attribute, attr);
+
+	return sysfs_emit(buf, "%s\n", (char *)eattr->var);
+}
+
+static ssize_t hisi_pcie_event_sysfs_show(struct device *dev,
+				   struct device_attribute *attr, char *buf)
+{
+	struct perf_pmu_events_attr *pmu_attr =
+		container_of(attr, struct perf_pmu_events_attr, attr);
+
+	return sysfs_emit(buf, "config=0x%llx\n", pmu_attr->id);
+}
+
+#define HISI_PCIE_PMU_FORMAT_ATTR(_name, _format)                              \
+	(&((struct dev_ext_attribute[]){                                       \
+		{ .attr = __ATTR(_name, 0444, hisi_pcie_format_sysfs_show,     \
+				 NULL),                                        \
+		  .var = (void *)_format }                                     \
+	})[0].attr.attr)
+
+#define HISI_PCIE_PMU_EVENT_ATTR(_name, _id)			\
+	PMU_EVENT_ATTR_ID(_name, hisi_pcie_event_sysfs_show, _id)
+
+static ssize_t cpumask_show(struct device *dev, struct device_attribute *attr,
+			    char *buf)
+{
+	struct hisi_pcie_pmu *pcie_pmu = to_pcie_pmu(dev_get_drvdata(dev));
+
+	return cpumap_print_to_pagebuf(true, buf, cpumask_of(pcie_pmu->on_cpu));
+}
+static DEVICE_ATTR_RO(cpumask);
+
+static ssize_t identifier_show(struct device *dev,
+			       struct device_attribute *attr, char *buf)
+{
+	struct hisi_pcie_pmu *pcie_pmu = to_pcie_pmu(dev_get_drvdata(dev));
+
+	return sysfs_emit(buf, "%#x\n", pcie_pmu->identifier);
+}
+static DEVICE_ATTR_RO(identifier);
+
+static ssize_t bus_show(struct device *dev, struct device_attribute *attr,
+			char *buf)
+{
+	struct hisi_pcie_pmu *pcie_pmu = to_pcie_pmu(dev_get_drvdata(dev));
+
+	return sysfs_emit(buf, "%#04x\n", PCI_BUS_NUM(pcie_pmu->bdf_min));
+}
+static DEVICE_ATTR_RO(bus);
+
+static struct hisi_pcie_reg_pair
+hisi_pcie_parse_reg_value(struct hisi_pcie_pmu *pcie_pmu, u32 reg_off)
+{
+	u32 val = readl_relaxed(pcie_pmu->base + reg_off);
+	struct hisi_pcie_reg_pair regs = {
+		.lo = val,
+		.hi = val >> 16,
+	};
+
+	return regs;
+}
+
+/*
+ * Hardware counter and ext_counter work together for bandwidth, latency,
+ * bus utilization and buffer occupancy events. For example, for latency
+ * events(idx = 0x10), counter counts total delay cycles and ext_counter
+ * counts PCIe packets number.
+ *
+ * As we don't want PMU driver to process these two data, "delay cycles"
+ * can be treated as an event(id = 0x10), "packets number" as another event
+ * (id = 0x10 << 8), and driver could export these data separately. So in
+ * this function, the "real" event idx is get to set HISI_PCIE_EVENT_CTRL.
+ */
+static u32 hisi_pcie_pmu_get_real_idx(struct perf_event *event)
+{
+	u32 event_idx = hisi_pcie_get_event(event);
+
+	if (!EXT_COUNTER_IS_USED(event_idx))
+		return event_idx;
+
+	return FIELD_GET(GENMASK(15, 8), event_idx);
+}
+
+static u32 hisi_pcie_pmu_get_offset(u32 offset, u32 idx)
+{
+	return offset + HISI_PCIE_REG_STEP * idx;
+}
+
+static u32 hisi_pcie_pmu_readl(struct hisi_pcie_pmu *pcie_pmu, u32 reg_offset,
+			       u32 idx)
+{
+	u32 offset = hisi_pcie_pmu_get_offset(reg_offset, idx);
+
+	return readl_relaxed(pcie_pmu->base + offset);
+}
+
+static void hisi_pcie_pmu_writel(struct hisi_pcie_pmu *pcie_pmu, u32 reg_offset,
+				 u32 idx, u32 val)
+{
+	u32 offset = hisi_pcie_pmu_get_offset(reg_offset, idx);
+
+	writel_relaxed(val, pcie_pmu->base + offset);
+}
+
+static u64 hisi_pcie_pmu_readq(struct hisi_pcie_pmu *pcie_pmu, u32 reg_offset,
+			       u32 idx)
+{
+	u32 offset = hisi_pcie_pmu_get_offset(reg_offset, idx);
+
+	return readq_relaxed(pcie_pmu->base + offset);
+}
+
+static void hisi_pcie_pmu_writeq(struct hisi_pcie_pmu *pcie_pmu, u32 reg_offset,
+				 u32 idx, u64 val)
+{
+	u32 offset = hisi_pcie_pmu_get_offset(reg_offset, idx);
+
+	writeq_relaxed(val, pcie_pmu->base + offset);
+}
+
+static void hisi_pcie_pmu_config_filter(struct perf_event *event)
+{
+	struct hisi_pcie_pmu *pcie_pmu = to_pcie_pmu(event->pmu);
+	u32 event_idx = hisi_pcie_pmu_get_real_idx(event);
+	struct hw_perf_event *hwc = &event->hw;
+	u64 reg = HISI_PCIE_DEFAULT_SET;
+	u64 port, trig_len, thr_len;
+	u32 idx = hwc->idx;
+
+	/* Config HISI_PCIE_EVENT_CTRL according to event and subevent. */
+	reg |= FIELD_PREP(HISI_PCIE_EVENT_M, event_idx) |
+	       FIELD_PREP(HISI_PCIE_SUBEVENT_M, hisi_pcie_get_subevent(event));
+
+	/* Config HISI_PCIE_EVENT_CTRL according to ROOT PORT or EP device. */
+	port = hisi_pcie_get_port(event);
+	if (port)
+		reg |= FIELD_PREP(HISI_PCIE_TARGET_M, port);
+	else
+		reg |= HISI_PCIE_TARGET_EN |
+		       FIELD_PREP(HISI_PCIE_TARGET_M, hisi_pcie_get_bdf(event));
+
+	/* Config HISI_PCIE_EVENT_CTRL according to trigger condition. */
+	trig_len = hisi_pcie_get_trig_len(event);
+	if (trig_len) {
+		reg |= FIELD_PREP(HISI_PCIE_TRIG_M, trig_len);
+		reg |= FIELD_PREP(HISI_PCIE_TRIG_MODE_M,
+				  hisi_pcie_get_trig_mode(event));
+		reg |= HISI_PCIE_TRIG_EN;
+	}
+
+	/* Config HISI_PCIE_EVENT_CTRL according to threshold condition. */
+	thr_len = hisi_pcie_get_thr_len(event);
+	if (thr_len) {
+		reg |= FIELD_PREP(HISI_PCIE_THR_M, thr_len);
+		reg |= FIELD_PREP(HISI_PCIE_THR_MODE_M,
+		       hisi_pcie_get_thr_mode(event));
+		reg |= HISI_PCIE_THR_EN;
+	}
+
+	hisi_pcie_pmu_writeq(pcie_pmu, HISI_PCIE_EVENT_CTRL, idx, reg);
+}
+
+static void hisi_pcie_pmu_clear_filter(struct perf_event *event)
+{
+	struct hisi_pcie_pmu *pcie_pmu = to_pcie_pmu(event->pmu);
+	struct hw_perf_event *hwc = &event->hw;
+
+	hisi_pcie_pmu_writeq(pcie_pmu, HISI_PCIE_EVENT_CTRL, hwc->idx,
+			     HISI_PCIE_DEFAULT_SET);
+}
+
+static bool hisi_pcie_pmu_valid_port(struct hisi_pcie_pmu *pcie_pmu, u16 rp_bdf)
+{
+	return rp_bdf >= pcie_pmu->bdf_min && rp_bdf <= pcie_pmu->bdf_max;
+}
+
+static bool hisi_pcie_pmu_valid_requester_id(struct hisi_pcie_pmu *pcie_pmu,
+					     u32 bdf)
+{
+	struct pci_dev *root_port, *pdev;
+
+	pdev = pci_get_domain_bus_and_slot(pci_domain_nr(pcie_pmu->pdev->bus),
+					   PCI_BUS_NUM(bdf),
+					   GET_PCI_DEVFN(bdf));
+	if (!pdev)
+		return false;
+
+	root_port = pcie_find_root_port(pdev);
+	if (!root_port)
+		return false;
+
+	pci_dev_put(pdev);
+	return hisi_pcie_pmu_valid_port(pcie_pmu, pci_dev_id(root_port));
+}
+
+static bool hisi_pcie_pmu_valid_filter(struct perf_event *event,
+				       struct hisi_pcie_pmu *pcie_pmu)
+{
+	u32 event_idx = hisi_pcie_pmu_get_real_idx(event);
+	u32 subev_idx = hisi_pcie_get_subevent(event);
+	u32 requester_id = hisi_pcie_get_bdf(event);
+
+	if (subev_idx > HISI_PCIE_SUBEVENT_MAX ||
+	    event_idx > HISI_PCIE_EVENT_MAX)
+		return false;
+
+	if (hisi_pcie_get_thr_len(event) > HISI_PCIE_THR_MAX_VAL)
+		return false;
+
+	if (hisi_pcie_get_trig_len(event) > HISI_PCIE_TRIG_MAX_VAL)
+		return false;
+
+	if (requester_id) {
+		if (!hisi_pcie_pmu_valid_requester_id(pcie_pmu, requester_id))
+			return false;
+	}
+
+	return true;
+}
+
+static bool hisi_pcie_pmu_validate_event_group(struct perf_event *event)
+{
+	struct perf_event *sibling, *leader = event->group_leader;
+	int counters = 1;
+
+	if (!is_software_event(leader)) {
+		if (leader->pmu != event->pmu)
+			return false;
+
+		if (leader != event)
+			counters++;
+	}
+
+	for_each_sibling_event(sibling, event->group_leader) {
+		if (is_software_event(sibling))
+			continue;
+
+		if (sibling->pmu != event->pmu)
+			return false;
+
+		counters++;
+	}
+
+	return counters <= HISI_PCIE_MAX_COUNTERS;
+}
+
+static int hisi_pcie_pmu_event_init(struct perf_event *event)
+{
+	struct hisi_pcie_pmu *pcie_pmu = to_pcie_pmu(event->pmu);
+
+	event->cpu = pcie_pmu->on_cpu;
+
+	if (event->attr.type != event->pmu->type)
+		return -ENOENT;
+
+	/* Sampling is not supported. */
+	if (is_sampling_event(event) || event->attach_state & PERF_ATTACH_TASK)
+		return -EOPNOTSUPP;
+
+	if (!hisi_pcie_pmu_valid_filter(event, pcie_pmu)) {
+		pci_err(pcie_pmu->pdev, "Invalid filter!\n");
+		return -EINVAL;
+	}
+
+	if (!hisi_pcie_pmu_validate_event_group(event))
+		return -EINVAL;
+
+	return 0;
+}
+
+static u64 hisi_pcie_pmu_read_counter(struct perf_event *event)
+{
+	struct hisi_pcie_pmu *pcie_pmu = to_pcie_pmu(event->pmu);
+	u32 event_idx = hisi_pcie_get_event(event);
+	u32 idx = event->hw.idx;
+
+	if (EXT_COUNTER_IS_USED(event_idx))
+		return hisi_pcie_pmu_readq(pcie_pmu, HISI_PCIE_EXT_CNT, idx);
+
+	return hisi_pcie_pmu_readq(pcie_pmu, HISI_PCIE_CNT, idx);
+}
+
+static void hisi_pcie_pmu_write_counter(struct perf_event *event, u64 val)
+{
+	struct hisi_pcie_pmu *pcie_pmu = to_pcie_pmu(event->pmu);
+	u32 event_idx = hisi_pcie_get_event(event);
+	u32 idx = event->hw.idx;
+
+	if (EXT_COUNTER_IS_USED(event_idx))
+		hisi_pcie_pmu_writeq(pcie_pmu, HISI_PCIE_EXT_CNT, idx, val);
+	else
+		hisi_pcie_pmu_writeq(pcie_pmu, HISI_PCIE_CNT, idx, val);
+}
+
+static int hisi_pcie_pmu_get_event_idx(struct hisi_pcie_pmu *pcie_pmu)
+{
+	int idx;
+
+	for (idx = 0; idx < HISI_PCIE_MAX_COUNTERS; idx++) {
+		if (!pcie_pmu->hw_events[idx])
+			return idx;
+	}
+
+	return -EINVAL;
+}
+
+static void hisi_pcie_pmu_event_update(struct perf_event *event)
+{
+	struct hw_perf_event *hwc = &event->hw;
+	u64 new_cnt, prev_cnt, delta;
+
+	do {
+		prev_cnt = local64_read(&hwc->prev_count);
+		new_cnt = hisi_pcie_pmu_read_counter(event);
+	} while (local64_cmpxchg(&hwc->prev_count, prev_cnt,
+				 new_cnt) != prev_cnt);
+
+	delta = (new_cnt - prev_cnt) & HISI_PCIE_MAX_PERIOD;
+	local64_add(delta, &event->count);
+}
+
+static void hisi_pcie_pmu_read(struct perf_event *event)
+{
+	hisi_pcie_pmu_event_update(event);
+}
+
+static void hisi_pcie_pmu_set_period(struct perf_event *event)
+{
+	struct hw_perf_event *hwc = &event->hw;
+
+	local64_set(&hwc->prev_count, HISI_PCIE_DEFAULT_VALUE);
+	hisi_pcie_pmu_write_counter(event, HISI_PCIE_DEFAULT_VALUE);
+}
+
+static void hisi_pcie_pmu_enable_counter(struct hisi_pcie_pmu *pcie_pmu,
+					 struct hw_perf_event *hwc)
+{
+	u32 idx = hwc->idx;
+	u64 val;
+
+	val = hisi_pcie_pmu_readq(pcie_pmu, HISI_PCIE_EVENT_CTRL, idx);
+	val |= HISI_PCIE_EVENT_EN;
+	hisi_pcie_pmu_writeq(pcie_pmu, HISI_PCIE_EVENT_CTRL, idx, val);
+}
+
+static void hisi_pcie_pmu_disable_counter(struct hisi_pcie_pmu *pcie_pmu,
+					  struct hw_perf_event *hwc)
+{
+	u32 idx = hwc->idx;
+	u64 val;
+
+	val = hisi_pcie_pmu_readq(pcie_pmu, HISI_PCIE_EVENT_CTRL, idx);
+	val &= ~HISI_PCIE_EVENT_EN;
+	hisi_pcie_pmu_writeq(pcie_pmu, HISI_PCIE_EVENT_CTRL, idx, val);
+}
+
+static void hisi_pcie_pmu_enable_int(struct hisi_pcie_pmu *pcie_pmu,
+				     struct hw_perf_event *hwc)
+{
+	u32 idx = hwc->idx;
+
+	hisi_pcie_pmu_writel(pcie_pmu, HISI_PCIE_INT_MASK, idx, 0);
+}
+
+static void hisi_pcie_pmu_disable_int(struct hisi_pcie_pmu *pcie_pmu,
+				      struct hw_perf_event *hwc)
+{
+	u32 idx = hwc->idx;
+
+	hisi_pcie_pmu_writel(pcie_pmu, HISI_PCIE_INT_MASK, idx, 1);
+}
+
+static void hisi_pcie_pmu_reset_counter(struct hisi_pcie_pmu *pcie_pmu,
+					struct hw_perf_event *hwc)
+{
+	u32 idx = hwc->idx;
+
+	hisi_pcie_pmu_writeq(pcie_pmu, HISI_PCIE_EVENT_CTRL, idx,
+			     HISI_PCIE_RESET_CNT);
+	hisi_pcie_pmu_writeq(pcie_pmu, HISI_PCIE_EVENT_CTRL, idx,
+			     HISI_PCIE_DEFAULT_SET);
+}
+
+static void hisi_pcie_pmu_start(struct perf_event *event, int flags)
+{
+	struct hisi_pcie_pmu *pcie_pmu = to_pcie_pmu(event->pmu);
+	struct hw_perf_event *hwc = &event->hw;
+	u64 prev_cnt;
+
+	if (WARN_ON_ONCE(!(hwc->state & PERF_HES_STOPPED)))
+		return;
+
+	WARN_ON_ONCE(!(hwc->state & PERF_HES_UPTODATE));
+	hwc->state = 0;
+
+	hisi_pcie_pmu_config_filter(event);
+	hisi_pcie_pmu_enable_counter(pcie_pmu, hwc);
+	hisi_pcie_pmu_enable_int(pcie_pmu, hwc);
+	hisi_pcie_pmu_set_period(event);
+
+	if (flags & PERF_EF_RELOAD) {
+		prev_cnt = local64_read(&hwc->prev_count);
+		hisi_pcie_pmu_write_counter(event, prev_cnt);
+	}
+
+	perf_event_update_userpage(event);
+}
+
+static void hisi_pcie_pmu_stop(struct perf_event *event, int flags)
+{
+	struct hisi_pcie_pmu *pcie_pmu = to_pcie_pmu(event->pmu);
+	struct hw_perf_event *hwc = &event->hw;
+
+	hisi_pcie_pmu_event_update(event);
+	hisi_pcie_pmu_disable_int(pcie_pmu, hwc);
+	hisi_pcie_pmu_disable_counter(pcie_pmu, hwc);
+	hisi_pcie_pmu_clear_filter(event);
+	WARN_ON_ONCE(hwc->state & PERF_HES_STOPPED);
+	hwc->state |= PERF_HES_STOPPED;
+
+	if (hwc->state & PERF_HES_UPTODATE)
+		return;
+
+	hwc->state |= PERF_HES_UPTODATE;
+}
+
+static int hisi_pcie_pmu_add(struct perf_event *event, int flags)
+{
+	struct hisi_pcie_pmu *pcie_pmu = to_pcie_pmu(event->pmu);
+	struct hw_perf_event *hwc = &event->hw;
+	int idx;
+
+	hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE;
+	idx = hisi_pcie_pmu_get_event_idx(pcie_pmu);
+	if (idx < 0)
+		return idx;
+
+	hwc->idx = idx;
+	pcie_pmu->hw_events[idx] = event;
+
+	/* Reset Counter to avoid interference caused by previous statistic. */
+	hisi_pcie_pmu_reset_counter(pcie_pmu, hwc);
+
+	if (flags & PERF_EF_START)
+		hisi_pcie_pmu_start(event, PERF_EF_RELOAD);
+
+	return 0;
+}
+
+static void hisi_pcie_pmu_del(struct perf_event *event, int flags)
+{
+	struct hisi_pcie_pmu *pcie_pmu = to_pcie_pmu(event->pmu);
+	struct hw_perf_event *hwc = &event->hw;
+
+	hisi_pcie_pmu_stop(event, PERF_EF_UPDATE);
+	pcie_pmu->hw_events[hwc->idx] = NULL;
+	perf_event_update_userpage(event);
+}
+
+static void hisi_pcie_pmu_enable(struct pmu *pmu)
+{
+	struct hisi_pcie_pmu *pcie_pmu = to_pcie_pmu(pmu);
+	int num;
+
+	for (num = 0; num < HISI_PCIE_MAX_COUNTERS; num++) {
+		if (pcie_pmu->hw_events[num])
+			break;
+	}
+
+	if (num == HISI_PCIE_MAX_COUNTERS)
+		return;
+
+	writel(HISI_PCIE_GLOBAL_EN, pcie_pmu->base + HISI_PCIE_GLOBAL_CTRL);
+}
+
+static void hisi_pcie_pmu_disable(struct pmu *pmu)
+{
+	struct hisi_pcie_pmu *pcie_pmu = to_pcie_pmu(pmu);
+
+	writel(HISI_PCIE_GLOBAL_NONE, pcie_pmu->base + HISI_PCIE_GLOBAL_CTRL);
+}
+
+static irqreturn_t hisi_pcie_pmu_irq(int irq, void *data)
+{
+	struct hisi_pcie_pmu *pcie_pmu = data;
+	irqreturn_t ret = IRQ_NONE;
+	struct perf_event *event;
+	u32 overflown;
+	int idx;
+
+	for (idx = 0; idx < HISI_PCIE_MAX_COUNTERS; idx++) {
+		overflown = hisi_pcie_pmu_readl(pcie_pmu, HISI_PCIE_INT_STAT,
+						idx);
+		if (!overflown)
+			continue;
+
+		/* Clear status of interrupt. */
+		hisi_pcie_pmu_writel(pcie_pmu, HISI_PCIE_INT_STAT, idx, 1);
+		event = pcie_pmu->hw_events[idx];
+		if (!event)
+			continue;
+
+		hisi_pcie_pmu_event_update(event);
+		hisi_pcie_pmu_set_period(event);
+		ret = IRQ_HANDLED;
+	}
+
+	return ret;
+}
+
+static int hisi_pcie_pmu_irq_register(struct pci_dev *pdev,
+				      struct hisi_pcie_pmu *pcie_pmu)
+{
+	int irq, ret;
+
+	ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSI);
+	if (ret < 0) {
+		pci_err(pdev, "Failed to enable MSI vectors: %d!\n", ret);
+		return ret;
+	}
+
+	irq = pci_irq_vector(pdev, 0);
+	ret = request_irq(irq, hisi_pcie_pmu_irq,
+			  IRQF_NOBALANCING | IRQF_NO_THREAD, "hisi_pcie_pmu",
+			  pcie_pmu);
+	if (ret) {
+		pci_err(pdev, "Failed to register IRQ: %d!\n", ret);
+		pci_free_irq_vectors(pdev);
+		return ret;
+	}
+
+	pcie_pmu->irq = irq;
+
+	return 0;
+}
+
+static void hisi_pcie_pmu_irq_unregister(struct pci_dev *pdev,
+					 struct hisi_pcie_pmu *pcie_pmu)
+{
+	free_irq(pcie_pmu->irq, pcie_pmu);
+	pci_free_irq_vectors(pdev);
+}
+
+static int hisi_pcie_pmu_online_cpu(unsigned int cpu, struct hlist_node *node)
+{
+	struct hisi_pcie_pmu *pcie_pmu = hlist_entry_safe(node,
+					 struct hisi_pcie_pmu, node);
+
+	if (pcie_pmu->on_cpu == -1) {
+		pcie_pmu->on_cpu = cpu;
+		WARN_ON(irq_set_affinity(pcie_pmu->irq, cpumask_of(cpu)));
+	}
+
+	return 0;
+}
+
+static int hisi_pcie_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
+{
+	struct hisi_pcie_pmu *pcie_pmu = hlist_entry_safe(node,
+					 struct hisi_pcie_pmu, node);
+	unsigned int target;
+
+	/* Nothing to do if this CPU doesn't own the PMU */
+	if (pcie_pmu->on_cpu != cpu)
+		return 0;
+
+	/* Choose a new CPU from all online cpus. */
+	target = cpumask_first(cpu_online_mask);
+	if (target >= nr_cpu_ids) {
+		pci_err(pcie_pmu->pdev, "There is no CPU to set!\n");
+		return 0;
+	}
+
+	perf_pmu_migrate_context(&pcie_pmu->pmu, cpu, target);
+	/* Use this CPU for event counting */
+	pcie_pmu->on_cpu = target;
+	WARN_ON(irq_set_affinity(pcie_pmu->irq, cpumask_of(target)));
+
+	return 0;
+}
+
+/*
+ * Events with the "dl" suffix in their names count performance in DL layer,
+ * otherswise, events count performance in TL layer.
+ */
+static struct attribute *hisi_pcie_pmu_events_attr[] = {
+	HISI_PCIE_PMU_EVENT_ATTR(bw_rx_mwr, 0x010004),
+	HISI_PCIE_PMU_EVENT_ATTR(bw_rx_mrd, 0x100005),
+	HISI_PCIE_PMU_EVENT_ATTR(bw_tx_mwr, 0x010005),
+	HISI_PCIE_PMU_EVENT_ATTR(bw_tx_mrd, 0x200004),
+	HISI_PCIE_PMU_EVENT_ATTR(lat_rx_mwr, 0x000010),
+	HISI_PCIE_PMU_EVENT_ATTR(lat_rx_mrd, 0x020010),
+	HISI_PCIE_PMU_EVENT_ATTR(lat_tx_mrd, 0x000011),
+	HISI_PCIE_PMU_EVENT_ATTR(bw_rx_dl, 0x010084),
+	HISI_PCIE_PMU_EVENT_ATTR(bw_tx_dl, 0x030084),
+	NULL
+};
+
+static struct attribute_group hisi_pcie_pmu_events_group = {
+	.name = "events",
+	.attrs = hisi_pcie_pmu_events_attr,
+};
+
+static struct attribute *hisi_pcie_pmu_format_attr[] = {
+	HISI_PCIE_PMU_FORMAT_ATTR(event, "config:0-15"),
+	HISI_PCIE_PMU_FORMAT_ATTR(subevent, "config:16-23"),
+	HISI_PCIE_PMU_FORMAT_ATTR(thr_len, "config1:0-3"),
+	HISI_PCIE_PMU_FORMAT_ATTR(thr_mode, "config1:4"),
+	HISI_PCIE_PMU_FORMAT_ATTR(trig_len, "config1:5-8"),
+	HISI_PCIE_PMU_FORMAT_ATTR(trig_mode, "config1:9"),
+	HISI_PCIE_PMU_FORMAT_ATTR(port, "config2:0-15"),
+	HISI_PCIE_PMU_FORMAT_ATTR(bdf, "config2:16-31"),
+	NULL
+};
+
+static const struct attribute_group hisi_pcie_pmu_format_group = {
+	.name = "format",
+	.attrs = hisi_pcie_pmu_format_attr,
+};
+
+static struct attribute *hisi_pcie_pmu_bus_attrs[] = {
+	&dev_attr_bus.attr,
+	NULL
+};
+
+static const struct attribute_group hisi_pcie_pmu_bus_attr_group = {
+	.attrs = hisi_pcie_pmu_bus_attrs,
+};
+
+static struct attribute *hisi_pcie_pmu_cpumask_attrs[] = {
+	&dev_attr_cpumask.attr,
+	NULL
+};
+
+static const struct attribute_group hisi_pcie_pmu_cpumask_attr_group = {
+	.attrs = hisi_pcie_pmu_cpumask_attrs,
+};
+
+static struct attribute *hisi_pcie_pmu_identifier_attrs[] = {
+	&dev_attr_identifier.attr,
+	NULL
+};
+
+static const struct attribute_group hisi_pcie_pmu_identifier_attr_group = {
+	.attrs = hisi_pcie_pmu_identifier_attrs,
+};
+
+static const struct attribute_group *hisi_pcie_pmu_attr_groups[] = {
+	&hisi_pcie_pmu_events_group,
+	&hisi_pcie_pmu_format_group,
+	&hisi_pcie_pmu_bus_attr_group,
+	&hisi_pcie_pmu_cpumask_attr_group,
+	&hisi_pcie_pmu_identifier_attr_group,
+	NULL
+};
+
+static int hisi_pcie_alloc_pmu(struct pci_dev *pdev,
+			       struct hisi_pcie_pmu *pcie_pmu)
+{
+	struct hisi_pcie_reg_pair regs;
+	u16 sicl_id, device_id;
+	char *name;
+
+	regs = hisi_pcie_parse_reg_value(pcie_pmu, HISI_PCIE_REG_BDF);
+	pcie_pmu->bdf_min = regs.lo;
+	pcie_pmu->bdf_max = regs.hi;
+
+	regs = hisi_pcie_parse_reg_value(pcie_pmu, HISI_PCIE_REG_INFO);
+	sicl_id = regs.hi;
+	device_id = regs.lo;
+
+	name = devm_kasprintf(&pdev->dev, GFP_KERNEL,
+			      "hisi_pcie%u_%u", sicl_id, device_id);
+	if (!name)
+		return -ENOMEM;
+
+	pcie_pmu->pdev = pdev;
+	pcie_pmu->on_cpu = -1;
+	pcie_pmu->identifier = readl(pcie_pmu->base + HISI_PCIE_REG_VERSION);
+	pcie_pmu->pmu = (struct pmu) {
+		.name		= name,
+		.module		= THIS_MODULE,
+		.event_init	= hisi_pcie_pmu_event_init,
+		.pmu_enable	= hisi_pcie_pmu_enable,
+		.pmu_disable	= hisi_pcie_pmu_disable,
+		.add		= hisi_pcie_pmu_add,
+		.del		= hisi_pcie_pmu_del,
+		.start		= hisi_pcie_pmu_start,
+		.stop		= hisi_pcie_pmu_stop,
+		.read		= hisi_pcie_pmu_read,
+		.task_ctx_nr	= perf_invalid_context,
+		.attr_groups	= hisi_pcie_pmu_attr_groups,
+		.capabilities	= PERF_PMU_CAP_NO_EXCLUDE,
+	};
+
+	return 0;
+}
+
+static int hisi_pcie_init_pmu(struct pci_dev *pdev,
+			      struct hisi_pcie_pmu *pcie_pmu)
+{
+	int ret;
+
+	pcie_pmu->base = pci_ioremap_bar(pdev, 2);
+	if (!pcie_pmu->base) {
+		pci_err(pdev, "Ioremap failed for pcie_pmu resource.\n");
+		return -ENOMEM;
+	}
+
+	ret = hisi_pcie_alloc_pmu(pdev, pcie_pmu);
+	if (ret)
+		return ret;
+
+	ret = hisi_pcie_pmu_irq_register(pdev, pcie_pmu);
+	if (ret)
+		goto err_set_pmu_fail;
+
+	ret = cpuhp_state_add_instance(CPUHP_AP_PERF_ARM_HISI_PCIE_PMU_ONLINE,
+				       &pcie_pmu->node);
+	if (ret) {
+		pci_err(pdev, "Failed to register hotplug: %d.\n", ret);
+		goto err_irq_unregister;
+	}
+
+	ret = perf_pmu_register(&pcie_pmu->pmu, pcie_pmu->pmu.name, -1);
+	if (ret) {
+		pci_err(pdev, "Failed to register PCIe PMU: %d.\n", ret);
+		goto err_hotplug_unregister;
+	}
+
+	return ret;
+
+err_hotplug_unregister:
+	cpuhp_state_remove_instance_nocalls(
+		CPUHP_AP_PERF_ARM_HISI_PCIE_PMU_ONLINE, &pcie_pmu->node);
+
+err_irq_unregister:
+	hisi_pcie_pmu_irq_unregister(pdev, pcie_pmu);
+
+err_set_pmu_fail:
+	iounmap(pcie_pmu->base);
+
+	return ret;
+}
+
+static void hisi_pcie_uninit_pmu(struct pci_dev *pdev)
+{
+	struct hisi_pcie_pmu *pcie_pmu = pci_get_drvdata(pdev);
+
+	perf_pmu_unregister(&pcie_pmu->pmu);
+	cpuhp_state_remove_instance_nocalls(
+		CPUHP_AP_PERF_ARM_HISI_PCIE_PMU_ONLINE, &pcie_pmu->node);
+	hisi_pcie_pmu_irq_unregister(pdev, pcie_pmu);
+	iounmap(pcie_pmu->base);
+}
+
+static int hisi_pcie_init_dev(struct pci_dev *pdev)
+{
+	int ret;
+
+	ret = pci_enable_device(pdev);
+	if (ret) {
+		pci_err(pdev, "Failed to enable PCI device: %d.\n", ret);
+		return ret;
+	}
+
+	ret = pci_request_mem_regions(pdev, "hisi_pcie_pmu");
+	if (ret < 0) {
+		pci_err(pdev, "Failed to request PCI mem regions: %d.\n", ret);
+		pci_disable_device(pdev);
+		return ret;
+	}
+
+	pci_set_master(pdev);
+
+	return 0;
+}
+
+static void hisi_pcie_uninit_dev(struct pci_dev *pdev)
+{
+	pci_clear_master(pdev);
+	pci_release_mem_regions(pdev);
+	pci_disable_device(pdev);
+}
+
+static int hisi_pcie_pmu_probe(struct pci_dev *pdev,
+			       const struct pci_device_id *id)
+{
+	struct hisi_pcie_pmu *pcie_pmu;
+	int ret;
+
+	pcie_pmu = devm_kzalloc(&pdev->dev, sizeof(*pcie_pmu), GFP_KERNEL);
+	if (!pcie_pmu)
+		return -ENOMEM;
+
+	ret = hisi_pcie_init_dev(pdev);
+	if (ret)
+		return ret;
+
+	ret = hisi_pcie_init_pmu(pdev, pcie_pmu);
+	if (ret)
+		hisi_pcie_uninit_dev(pdev);
+
+	pci_set_drvdata(pdev, pcie_pmu);
+
+	return ret;
+}
+
+static void hisi_pcie_pmu_remove(struct pci_dev *pdev)
+{
+	hisi_pcie_uninit_pmu(pdev);
+	hisi_pcie_uninit_dev(pdev);
+	pci_set_drvdata(pdev, NULL);
+}
+
+static const struct pci_device_id hisi_pcie_pmu_ids[] = {
+	{ PCI_DEVICE(PCI_VENDOR_ID_HUAWEI, 0xa12d) },
+	{ 0, }
+};
+MODULE_DEVICE_TABLE(pci, hisi_pcie_pmu_ids);
+
+static struct pci_driver hisi_pcie_pmu_driver = {
+	.name = "hisi_pcie_pmu",
+	.id_table = hisi_pcie_pmu_ids,
+	.probe = hisi_pcie_pmu_probe,
+	.remove = hisi_pcie_pmu_remove,
+};
+
+static int __init hisi_pcie_module_init(void)
+{
+	int ret;
+
+	ret = cpuhp_setup_state_multi(CPUHP_AP_PERF_ARM_HISI_PCIE_PMU_ONLINE,
+				      "AP_PERF_ARM_HISI_PCIE_PMU_ONLINE",
+				      hisi_pcie_pmu_online_cpu,
+				      hisi_pcie_pmu_offline_cpu);
+	if (ret) {
+		pr_err("Failed to setup PCIe PMU hotplug, ret = %d.\n", ret);
+		return ret;
+	}
+
+	ret = pci_register_driver(&hisi_pcie_pmu_driver);
+	if (ret)
+		cpuhp_remove_multi_state(
+				CPUHP_AP_PERF_ARM_HISI_PCIE_PMU_ONLINE);
+
+	return ret;
+}
+module_init(hisi_pcie_module_init);
+
+static void __exit hisi_pcie_module_exit(void)
+{
+	pci_unregister_driver(&hisi_pcie_pmu_driver);
+	cpuhp_remove_multi_state(CPUHP_AP_PERF_ARM_HISI_PCIE_PMU_ONLINE);
+}
+module_exit(hisi_pcie_module_exit);
+
+MODULE_DESCRIPTION("HiSilicon PCIe PMU driver");
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Qi Liu <liuqi115@huawei.com>");
diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
index 4a62b39..a9776a2 100644
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -180,6 +180,7 @@ enum cpuhp_state {
 	CPUHP_AP_PERF_ARM_HISI_L3_ONLINE,
 	CPUHP_AP_PERF_ARM_HISI_PA_ONLINE,
 	CPUHP_AP_PERF_ARM_HISI_SLLC_ONLINE,
+	CPUHP_AP_PERF_ARM_HISI_PCIE_PMU_ONLINE,
 	CPUHP_AP_PERF_ARM_L2X0_ONLINE,
 	CPUHP_AP_PERF_ARM_QCOM_L2_ONLINE,
 	CPUHP_AP_PERF_ARM_QCOM_L3_ONLINE,
-- 
2.7.4


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