Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted

Pull networking updates from Jakub Kicinski:
 "Core:

   - Add dedicated kmem_cache for typical/small skb->head, avoid having
     to access struct page at kfree time, and improve memory use.

   - Introduce sysctl to set default RPS configuration for new netdevs.

   - Define Netlink protocol specification format which can be used to
     describe messages used by each family and auto-generate parsers.
     Add tools for generating kernel data structures and uAPI headers.

   - Expose all net/core sysctls inside netns.

   - Remove 4s sleep in netpoll if carrier is instantly detected on
     boot.

   - Add configurable limit of MDB entries per port, and port-vlan.

   - Continue populating drop reasons throughout the stack.

   - Retire a handful of legacy Qdiscs and classifiers.

  Protocols:

   - Support IPv4 big TCP (TSO frames larger than 64kB).

   - Add IP_LOCAL_PORT_RANGE socket option, to control local port range
     on socket by socket basis.

   - Track and report in procfs number of MPTCP sockets used.

   - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
     manager.

   - IPv6: don't check net.ipv6.route.max_size and rely on garbage
     collection to free memory (similarly to IPv4).

   - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).

   - ICMP: add per-rate limit counters.

   - Add support for user scanning requests in ieee802154.

   - Remove static WEP support.

   - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
     reporting.

   - WiFi 7 EHT channel puncturing support (client & AP).

  BPF:

   - Add a rbtree data structure following the "next-gen data structure"
     precedent set by recently added linked list, that is, by using
     kfunc + kptr instead of adding a new BPF map type.

   - Expose XDP hints via kfuncs with initial support for RX hash and
     timestamp metadata.

   - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
     better support decap on GRE tunnel devices not operating in collect
     metadata.

   - Improve x86 JIT's codegen for PROBE_MEM runtime error checks.

   - Remove the need for trace_printk_lock for bpf_trace_printk and
     bpf_trace_vprintk helpers.

   - Extend libbpf's bpf_tracing.h support for tracing arguments of
     kprobes/uprobes and syscall as a special case.

   - Significantly reduce the search time for module symbols by
     livepatch and BPF.

   - Enable cpumasks to be used as kptrs, which is useful for tracing
     programs tracking which tasks end up running on which CPUs in
     different time intervals.

   - Add support for BPF trampoline on s390x and riscv64.

   - Add capability to export the XDP features supported by the NIC.

   - Add __bpf_kfunc tag for marking kernel functions as kfuncs.

   - Add cgroup.memory=nobpf kernel parameter option to disable BPF
     memory accounting for container environments.

  Netfilter:

   - Remove the CLUSTERIP target. It has been marked as obsolete for
     years, and we still have WARN splats wrt races of the out-of-band
     /proc interface installed by this target.

   - Add 'destroy' commands to nf_tables. They are identical to the
     existing 'delete' commands, but do not return an error if the
     referenced object (set, chain, rule...) did not exist.

  Driver API:

   - Improve cpumask_local_spread() locality to help NICs set the right
     IRQ affinity on AMD platforms.

   - Separate C22 and C45 MDIO bus transactions more clearly.

   - Introduce new DCB table to control DSCP rewrite on egress.

   - Support configuration of Physical Layer Collision Avoidance (PLCA)
     Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
     shared medium Ethernet.

   - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
     preemption of low priority frames by high priority frames.

   - Add support for controlling MACSec offload using netlink SET.

   - Rework devlink instance refcounts to allow registration and
     de-registration under the instance lock. Split the code into
     multiple files, drop some of the unnecessarily granular locks and
     factor out common parts of netlink operation handling.

   - Add TX frame aggregation parameters (for USB drivers).

   - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
     messages with notifications for debug.

   - Allow offloading of UDP NEW connections via act_ct.

   - Add support for per action HW stats in TC.

   - Support hardware miss to TC action (continue processing in SW from
     a specific point in the action chain).

   - Warn if old Wireless Extension user space interface is used with
     modern cfg80211/mac80211 drivers. Do not support Wireless
     Extensions for Wi-Fi 7 devices at all. Everyone should switch to
     using nl80211 interface instead.

   - Improve the CAN bit timing configuration. Use extack to return
     error messages directly to user space, update the SJW handling,
     including the definition of a new default value that will benefit
     CAN-FD controllers, by increasing their oscillator tolerance.

  New hardware / drivers:

   - Ethernet:
      - nVidia BlueField-3 support (control traffic driver)
      - Ethernet support for imx93 SoCs
      - Motorcomm yt8531 gigabit Ethernet PHY
      - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
      - Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
      - Amlogic gxl MDIO mux

   - WiFi:
      - RealTek RTL8188EU (rtl8xxxu)
      - Qualcomm Wi-Fi 7 devices (ath12k)

   - CAN:
      - Renesas R-Car V4H

  Drivers:

   - Bluetooth:
      - Set Per Platform Antenna Gain (PPAG) for Intel controllers.

   - Ethernet NICs:
      - Intel (1G, igc):
         - support TSN / Qbv / packet scheduling features of i226 model
      - Intel (100G, ice):
         - use GNSS subsystem instead of TTY
         - multi-buffer XDP support
         - extend support for GPIO pins to E823 devices
      - nVidia/Mellanox:
         - update the shared buffer configuration on PFC commands
         - implement PTP adjphase function for HW offset control
         - TC support for Geneve and GRE with VF tunnel offload
         - more efficient crypto key management method
         - multi-port eswitch support
      - Netronome/Corigine:
         - add DCB IEEE support
         - support IPsec offloading for NFP3800
      - Freescale/NXP (enetc):
         - support XDP_REDIRECT for XDP non-linear buffers
         - improve reconfig, avoid link flap and waiting for idle
         - support MAC Merge layer
      - Other NICs:
         - sfc/ef100: add basic devlink support for ef100
         - ionic: rx_push mode operation (writing descriptors via MMIO)
         - bnxt: use the auxiliary bus abstraction for RDMA
         - r8169: disable ASPM and reset bus in case of tx timeout
         - cpsw: support QSGMII mode for J721e CPSW9G
         - cpts: support pulse-per-second output
         - ngbe: add an mdio bus driver
         - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
         - r8152: handle devices with FW with NCM support
         - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
         - virtio-net: support multi buffer XDP
         - virtio/vsock: replace virtio_vsock_pkt with sk_buff
         - tsnep: XDP support

   - Ethernet high-speed switches:
      - nVidia/Mellanox (mlxsw):
         - add support for latency TLV (in FW control messages)
      - Microchip (sparx5):
         - separate explicit and implicit traffic forwarding rules, make
           the implicit rules always active
         - add support for egress DSCP rewrite
         - IS0 VCAP support (Ingress Classification)
         - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
           etc.)
         - ES2 VCAP support (Egress Access Control)
         - support for Per-Stream Filtering and Policing (802.1Q,
           8.6.5.1)

   - Ethernet embedded switches:
      - Marvell (mv88e6xxx):
         - add MAB (port auth) offload support
         - enable PTP receive for mv88e6390
      - NXP (ocelot):
         - support MAC Merge layer
         - support for the the vsc7512 internal copper phys
      - Microchip:
         - lan9303: convert to PHYLINK
         - lan966x: support TC flower filter statistics
         - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
         - lan937x: support Credit Based Shaper configuration
         - ksz9477: support Energy Efficient Ethernet
      - other:
         - qca8k: convert to regmap read/write API, use bulk operations
         - rswitch: Improve TX timestamp accuracy

   - Intel WiFi (iwlwifi):
      - EHT (Wi-Fi 7) rate reporting
      - STEP equalizer support: transfer some STEP (connection to radio
        on platforms with integrated wifi) related parameters from the
        BIOS to the firmware.

   - Qualcomm 802.11ax WiFi (ath11k):
      - IPQ5018 support
      - Fine Timing Measurement (FTM) responder role support
      - channel 177 support

   - MediaTek WiFi (mt76):
      - per-PHY LED support
      - mt7996: EHT (Wi-Fi 7) support
      - Wireless Ethernet Dispatch (WED) reset support
      - switch to using page pool allocator

   - RealTek WiFi (rtw89):
      - support new version of Bluetooth co-existance

   - Mobile:
      - rmnet: support TX aggregation"

* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
  page_pool: add a comment explaining the fragment counter usage
  net: ethtool: fix __ethtool_dev_mm_supported() implementation
  ethtool: pse-pd: Fix double word in comments
  xsk: add linux/vmalloc.h to xsk.c
  sefltests: netdevsim: wait for devlink instance after netns removal
  selftest: fib_tests: Always cleanup before exit
  net/mlx5e: Align IPsec ASO result memory to be as required by hardware
  net/mlx5e: TC, Set CT miss to the specific ct action instance
  net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
  net/mlx5: Refactor tc miss handling to a single function
  net/mlx5: Kconfig: Make tc offload depend on tc skb extension
  net/sched: flower: Support hardware miss to tc action
  net/sched: flower: Move filter handle initialization earlier
  net/sched: cls_api: Support hardware miss to tc action
  net/sched: Rename user cookie and act cookie
  sfc: fix builds without CONFIG_RTC_LIB
  sfc: clean up some inconsistent indentings
  net/mlx4_en: Introduce flexible array to silence overflow warning
  net: lan966x: Fix possible deadlock inside PTP
  net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
  ...

1 files changed, 1303 insertions, 0 deletions

diff --git a/drivers/perf/arm_cspmu/arm_cspmu.c b/drivers/perf/arm_cspmu/arm_cspmu.c
new file mode 100644
index 000000000..e31302ab7
--- /dev/null
+++ b/drivers/perf/arm_cspmu/arm_cspmu.c
@@ -0,0 +1,1303 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ARM CoreSight Architecture PMU driver.
+ *
+ * This driver adds support for uncore PMU based on ARM CoreSight Performance
+ * Monitoring Unit Architecture. The PMU is accessible via MMIO registers and
+ * like other uncore PMUs, it does not support process specific events and
+ * cannot be used in sampling mode.
+ *
+ * This code is based on other uncore PMUs like ARM DSU PMU. It provides a
+ * generic implementation to operate the PMU according to CoreSight PMU
+ * architecture and ACPI ARM PMU table (APMT) documents below:
+ *   - ARM CoreSight PMU architecture document number: ARM IHI 0091 A.a-00bet0.
+ *   - APMT document number: ARM DEN0117.
+ *
+ * The user should refer to the vendor technical documentation to get details
+ * about the supported events.
+ *
+ * Copyright (c) 2022, NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+ *
+ */
+
+#include <linux/acpi.h>
+#include <linux/cacheinfo.h>
+#include <linux/ctype.h>
+#include <linux/interrupt.h>
+#include <linux/io-64-nonatomic-lo-hi.h>
+#include <linux/module.h>
+#include <linux/perf_event.h>
+#include <linux/platform_device.h>
+#include <acpi/processor.h>
+
+#include "arm_cspmu.h"
+#include "nvidia_cspmu.h"
+
+#define PMUNAME "arm_cspmu"
+#define DRVNAME "arm-cs-arch-pmu"
+
+#define ARM_CSPMU_CPUMASK_ATTR(_name, _config)			\
+	ARM_CSPMU_EXT_ATTR(_name, arm_cspmu_cpumask_show,	\
+				(unsigned long)_config)
+
+/*
+ * CoreSight PMU Arch register offsets.
+ */
+#define PMEVCNTR_LO					0x0
+#define PMEVCNTR_HI					0x4
+#define PMEVTYPER					0x400
+#define PMCCFILTR					0x47C
+#define PMEVFILTR					0xA00
+#define PMCNTENSET					0xC00
+#define PMCNTENCLR					0xC20
+#define PMINTENSET					0xC40
+#define PMINTENCLR					0xC60
+#define PMOVSCLR					0xC80
+#define PMOVSSET					0xCC0
+#define PMCFGR						0xE00
+#define PMCR						0xE04
+#define PMIIDR						0xE08
+
+/* PMCFGR register field */
+#define PMCFGR_NCG					GENMASK(31, 28)
+#define PMCFGR_HDBG					BIT(24)
+#define PMCFGR_TRO					BIT(23)
+#define PMCFGR_SS					BIT(22)
+#define PMCFGR_FZO					BIT(21)
+#define PMCFGR_MSI					BIT(20)
+#define PMCFGR_UEN					BIT(19)
+#define PMCFGR_NA					BIT(17)
+#define PMCFGR_EX					BIT(16)
+#define PMCFGR_CCD					BIT(15)
+#define PMCFGR_CC					BIT(14)
+#define PMCFGR_SIZE					GENMASK(13, 8)
+#define PMCFGR_N					GENMASK(7, 0)
+
+/* PMCR register field */
+#define PMCR_TRO					BIT(11)
+#define PMCR_HDBG					BIT(10)
+#define PMCR_FZO					BIT(9)
+#define PMCR_NA						BIT(8)
+#define PMCR_DP						BIT(5)
+#define PMCR_X						BIT(4)
+#define PMCR_D						BIT(3)
+#define PMCR_C						BIT(2)
+#define PMCR_P						BIT(1)
+#define PMCR_E						BIT(0)
+
+/* Each SET/CLR register supports up to 32 counters. */
+#define ARM_CSPMU_SET_CLR_COUNTER_SHIFT		5
+#define ARM_CSPMU_SET_CLR_COUNTER_NUM		\
+	(1 << ARM_CSPMU_SET_CLR_COUNTER_SHIFT)
+
+/* Convert counter idx into SET/CLR register number. */
+#define COUNTER_TO_SET_CLR_ID(idx)			\
+	(idx >> ARM_CSPMU_SET_CLR_COUNTER_SHIFT)
+
+/* Convert counter idx into SET/CLR register bit. */
+#define COUNTER_TO_SET_CLR_BIT(idx)			\
+	(idx & (ARM_CSPMU_SET_CLR_COUNTER_NUM - 1))
+
+#define ARM_CSPMU_ACTIVE_CPU_MASK		0x0
+#define ARM_CSPMU_ASSOCIATED_CPU_MASK		0x1
+
+/* Check if field f in flags is set with value v */
+#define CHECK_APMT_FLAG(flags, f, v) \
+	((flags & (ACPI_APMT_FLAGS_ ## f)) == (ACPI_APMT_FLAGS_ ## f ## _ ## v))
+
+/* Check and use default if implementer doesn't provide attribute callback */
+#define CHECK_DEFAULT_IMPL_OPS(ops, callback)			\
+	do {							\
+		if (!ops->callback)				\
+			ops->callback = arm_cspmu_ ## callback;	\
+	} while (0)
+
+/*
+ * Maximum poll count for reading counter value using high-low-high sequence.
+ */
+#define HILOHI_MAX_POLL	1000
+
+/* JEDEC-assigned JEP106 identification code */
+#define ARM_CSPMU_IMPL_ID_NVIDIA		0x36B
+
+static unsigned long arm_cspmu_cpuhp_state;
+
+/*
+ * In CoreSight PMU architecture, all of the MMIO registers are 32-bit except
+ * counter register. The counter register can be implemented as 32-bit or 64-bit
+ * register depending on the value of PMCFGR.SIZE field. For 64-bit access,
+ * single-copy 64-bit atomic support is implementation defined. APMT node flag
+ * is used to identify if the PMU supports 64-bit single copy atomic. If 64-bit
+ * single copy atomic is not supported, the driver treats the register as a pair
+ * of 32-bit register.
+ */
+
+/*
+ * Read 64-bit register as a pair of 32-bit registers using hi-lo-hi sequence.
+ */
+static u64 read_reg64_hilohi(const void __iomem *addr, u32 max_poll_count)
+{
+	u32 val_lo, val_hi;
+	u64 val;
+
+	/* Use high-low-high sequence to avoid tearing */
+	do {
+		if (max_poll_count-- == 0) {
+			pr_err("ARM CSPMU: timeout hi-low-high sequence\n");
+			return 0;
+		}
+
+		val_hi = readl(addr + 4);
+		val_lo = readl(addr);
+	} while (val_hi != readl(addr + 4));
+
+	val = (((u64)val_hi << 32) | val_lo);
+
+	return val;
+}
+
+/* Check if PMU supports 64-bit single copy atomic. */
+static inline bool supports_64bit_atomics(const struct arm_cspmu *cspmu)
+{
+	return CHECK_APMT_FLAG(cspmu->apmt_node->flags, ATOMIC, SUPP);
+}
+
+/* Check if cycle counter is supported. */
+static inline bool supports_cycle_counter(const struct arm_cspmu *cspmu)
+{
+	return (cspmu->pmcfgr & PMCFGR_CC);
+}
+
+/* Get counter size, which is (PMCFGR_SIZE + 1). */
+static inline u32 counter_size(const struct arm_cspmu *cspmu)
+{
+	return FIELD_GET(PMCFGR_SIZE, cspmu->pmcfgr) + 1;
+}
+
+/* Get counter mask. */
+static inline u64 counter_mask(const struct arm_cspmu *cspmu)
+{
+	return GENMASK_ULL(counter_size(cspmu) - 1, 0);
+}
+
+/* Check if counter is implemented as 64-bit register. */
+static inline bool use_64b_counter_reg(const struct arm_cspmu *cspmu)
+{
+	return (counter_size(cspmu) > 32);
+}
+
+ssize_t arm_cspmu_sysfs_event_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct dev_ext_attribute *eattr =
+		container_of(attr, struct dev_ext_attribute, attr);
+	return sysfs_emit(buf, "event=0x%llx\n",
+			  (unsigned long long)eattr->var);
+}
+EXPORT_SYMBOL_GPL(arm_cspmu_sysfs_event_show);
+
+/* Default event list. */
+static struct attribute *arm_cspmu_event_attrs[] = {
+	ARM_CSPMU_EVENT_ATTR(cycles, ARM_CSPMU_EVT_CYCLES_DEFAULT),
+	NULL,
+};
+
+static struct attribute **
+arm_cspmu_get_event_attrs(const struct arm_cspmu *cspmu)
+{
+	struct attribute **attrs;
+
+	attrs = devm_kmemdup(cspmu->dev, arm_cspmu_event_attrs,
+		sizeof(arm_cspmu_event_attrs), GFP_KERNEL);
+
+	return attrs;
+}
+
+static umode_t
+arm_cspmu_event_attr_is_visible(struct kobject *kobj,
+				struct attribute *attr, int unused)
+{
+	struct device *dev = kobj_to_dev(kobj);
+	struct arm_cspmu *cspmu = to_arm_cspmu(dev_get_drvdata(dev));
+	struct perf_pmu_events_attr *eattr;
+
+	eattr = container_of(attr, typeof(*eattr), attr.attr);
+
+	/* Hide cycle event if not supported */
+	if (!supports_cycle_counter(cspmu) &&
+	    eattr->id == ARM_CSPMU_EVT_CYCLES_DEFAULT)
+		return 0;
+
+	return attr->mode;
+}
+
+ssize_t arm_cspmu_sysfs_format_show(struct device *dev,
+				struct device_attribute *attr,
+				char *buf)
+{
+	struct dev_ext_attribute *eattr =
+		container_of(attr, struct dev_ext_attribute, attr);
+	return sysfs_emit(buf, "%s\n", (char *)eattr->var);
+}
+EXPORT_SYMBOL_GPL(arm_cspmu_sysfs_format_show);
+
+static struct attribute *arm_cspmu_format_attrs[] = {
+	ARM_CSPMU_FORMAT_EVENT_ATTR,
+	ARM_CSPMU_FORMAT_FILTER_ATTR,
+	NULL,
+};
+
+static struct attribute **
+arm_cspmu_get_format_attrs(const struct arm_cspmu *cspmu)
+{
+	struct attribute **attrs;
+
+	attrs = devm_kmemdup(cspmu->dev, arm_cspmu_format_attrs,
+		sizeof(arm_cspmu_format_attrs), GFP_KERNEL);
+
+	return attrs;
+}
+
+static u32 arm_cspmu_event_type(const struct perf_event *event)
+{
+	return event->attr.config & ARM_CSPMU_EVENT_MASK;
+}
+
+static bool arm_cspmu_is_cycle_counter_event(const struct perf_event *event)
+{
+	return (event->attr.config == ARM_CSPMU_EVT_CYCLES_DEFAULT);
+}
+
+static u32 arm_cspmu_event_filter(const struct perf_event *event)
+{
+	return event->attr.config1 & ARM_CSPMU_FILTER_MASK;
+}
+
+static ssize_t arm_cspmu_identifier_show(struct device *dev,
+					 struct device_attribute *attr,
+					 char *page)
+{
+	struct arm_cspmu *cspmu = to_arm_cspmu(dev_get_drvdata(dev));
+
+	return sysfs_emit(page, "%s\n", cspmu->identifier);
+}
+
+static struct device_attribute arm_cspmu_identifier_attr =
+	__ATTR(identifier, 0444, arm_cspmu_identifier_show, NULL);
+
+static struct attribute *arm_cspmu_identifier_attrs[] = {
+	&arm_cspmu_identifier_attr.attr,
+	NULL,
+};
+
+static struct attribute_group arm_cspmu_identifier_attr_group = {
+	.attrs = arm_cspmu_identifier_attrs,
+};
+
+static const char *arm_cspmu_get_identifier(const struct arm_cspmu *cspmu)
+{
+	const char *identifier =
+		devm_kasprintf(cspmu->dev, GFP_KERNEL, "%x",
+			       cspmu->impl.pmiidr);
+	return identifier;
+}
+
+static const char *arm_cspmu_type_str[ACPI_APMT_NODE_TYPE_COUNT] = {
+	"mc",
+	"smmu",
+	"pcie",
+	"acpi",
+	"cache",
+};
+
+static const char *arm_cspmu_get_name(const struct arm_cspmu *cspmu)
+{
+	struct device *dev;
+	struct acpi_apmt_node *apmt_node;
+	u8 pmu_type;
+	char *name;
+	char acpi_hid_string[ACPI_ID_LEN] = { 0 };
+	static atomic_t pmu_idx[ACPI_APMT_NODE_TYPE_COUNT] = { 0 };
+
+	dev = cspmu->dev;
+	apmt_node = cspmu->apmt_node;
+	pmu_type = apmt_node->type;
+
+	if (pmu_type >= ACPI_APMT_NODE_TYPE_COUNT) {
+		dev_err(dev, "unsupported PMU type-%u\n", pmu_type);
+		return NULL;
+	}
+
+	if (pmu_type == ACPI_APMT_NODE_TYPE_ACPI) {
+		memcpy(acpi_hid_string,
+			&apmt_node->inst_primary,
+			sizeof(apmt_node->inst_primary));
+		name = devm_kasprintf(dev, GFP_KERNEL, "%s_%s_%s_%u", PMUNAME,
+				      arm_cspmu_type_str[pmu_type],
+				      acpi_hid_string,
+				      apmt_node->inst_secondary);
+	} else {
+		name = devm_kasprintf(dev, GFP_KERNEL, "%s_%s_%d", PMUNAME,
+				      arm_cspmu_type_str[pmu_type],
+				      atomic_fetch_inc(&pmu_idx[pmu_type]));
+	}
+
+	return name;
+}
+
+static ssize_t arm_cspmu_cpumask_show(struct device *dev,
+				      struct device_attribute *attr,
+				      char *buf)
+{
+	struct pmu *pmu = dev_get_drvdata(dev);
+	struct arm_cspmu *cspmu = to_arm_cspmu(pmu);
+	struct dev_ext_attribute *eattr =
+		container_of(attr, struct dev_ext_attribute, attr);
+	unsigned long mask_id = (unsigned long)eattr->var;
+	const cpumask_t *cpumask;
+
+	switch (mask_id) {
+	case ARM_CSPMU_ACTIVE_CPU_MASK:
+		cpumask = &cspmu->active_cpu;
+		break;
+	case ARM_CSPMU_ASSOCIATED_CPU_MASK:
+		cpumask = &cspmu->associated_cpus;
+		break;
+	default:
+		return 0;
+	}
+	return cpumap_print_to_pagebuf(true, buf, cpumask);
+}
+
+static struct attribute *arm_cspmu_cpumask_attrs[] = {
+	ARM_CSPMU_CPUMASK_ATTR(cpumask, ARM_CSPMU_ACTIVE_CPU_MASK),
+	ARM_CSPMU_CPUMASK_ATTR(associated_cpus, ARM_CSPMU_ASSOCIATED_CPU_MASK),
+	NULL,
+};
+
+static struct attribute_group arm_cspmu_cpumask_attr_group = {
+	.attrs = arm_cspmu_cpumask_attrs,
+};
+
+struct impl_match {
+	u32 pmiidr;
+	u32 mask;
+	int (*impl_init_ops)(struct arm_cspmu *cspmu);
+};
+
+static const struct impl_match impl_match[] = {
+	{
+	  .pmiidr = ARM_CSPMU_IMPL_ID_NVIDIA,
+	  .mask = ARM_CSPMU_PMIIDR_IMPLEMENTER,
+	  .impl_init_ops = nv_cspmu_init_ops
+	},
+	{}
+};
+
+static int arm_cspmu_init_impl_ops(struct arm_cspmu *cspmu)
+{
+	int ret;
+	struct acpi_apmt_node *apmt_node = cspmu->apmt_node;
+	struct arm_cspmu_impl_ops *impl_ops = &cspmu->impl.ops;
+	const struct impl_match *match = impl_match;
+
+	/*
+	 * Get PMU implementer and product id from APMT node.
+	 * If APMT node doesn't have implementer/product id, try get it
+	 * from PMIIDR.
+	 */
+	cspmu->impl.pmiidr =
+		(apmt_node->impl_id) ? apmt_node->impl_id :
+				       readl(cspmu->base0 + PMIIDR);
+
+	/* Find implementer specific attribute ops. */
+	for (; match->pmiidr; match++) {
+		const u32 mask = match->mask;
+
+		if ((match->pmiidr & mask) == (cspmu->impl.pmiidr & mask)) {
+			ret = match->impl_init_ops(cspmu);
+			if (ret)
+				return ret;
+
+			break;
+		}
+	}
+
+	/* Use default callbacks if implementer doesn't provide one. */
+	CHECK_DEFAULT_IMPL_OPS(impl_ops, get_event_attrs);
+	CHECK_DEFAULT_IMPL_OPS(impl_ops, get_format_attrs);
+	CHECK_DEFAULT_IMPL_OPS(impl_ops, get_identifier);
+	CHECK_DEFAULT_IMPL_OPS(impl_ops, get_name);
+	CHECK_DEFAULT_IMPL_OPS(impl_ops, is_cycle_counter_event);
+	CHECK_DEFAULT_IMPL_OPS(impl_ops, event_type);
+	CHECK_DEFAULT_IMPL_OPS(impl_ops, event_filter);
+	CHECK_DEFAULT_IMPL_OPS(impl_ops, event_attr_is_visible);
+
+	return 0;
+}
+
+static struct attribute_group *
+arm_cspmu_alloc_event_attr_group(struct arm_cspmu *cspmu)
+{
+	struct attribute_group *event_group;
+	struct device *dev = cspmu->dev;
+	const struct arm_cspmu_impl_ops *impl_ops = &cspmu->impl.ops;
+
+	event_group =
+		devm_kzalloc(dev, sizeof(struct attribute_group), GFP_KERNEL);
+	if (!event_group)
+		return NULL;
+
+	event_group->name = "events";
+	event_group->is_visible = impl_ops->event_attr_is_visible;
+	event_group->attrs = impl_ops->get_event_attrs(cspmu);
+
+	if (!event_group->attrs)
+		return NULL;
+
+	return event_group;
+}
+
+static struct attribute_group *
+arm_cspmu_alloc_format_attr_group(struct arm_cspmu *cspmu)
+{
+	struct attribute_group *format_group;
+	struct device *dev = cspmu->dev;
+
+	format_group =
+		devm_kzalloc(dev, sizeof(struct attribute_group), GFP_KERNEL);
+	if (!format_group)
+		return NULL;
+
+	format_group->name = "format";
+	format_group->attrs = cspmu->impl.ops.get_format_attrs(cspmu);
+
+	if (!format_group->attrs)
+		return NULL;
+
+	return format_group;
+}
+
+static struct attribute_group **
+arm_cspmu_alloc_attr_group(struct arm_cspmu *cspmu)
+{
+	struct attribute_group **attr_groups = NULL;
+	struct device *dev = cspmu->dev;
+	const struct arm_cspmu_impl_ops *impl_ops = &cspmu->impl.ops;
+	int ret;
+
+	ret = arm_cspmu_init_impl_ops(cspmu);
+	if (ret)
+		return NULL;
+
+	cspmu->identifier = impl_ops->get_identifier(cspmu);
+	cspmu->name = impl_ops->get_name(cspmu);
+
+	if (!cspmu->identifier || !cspmu->name)
+		return NULL;
+
+	attr_groups = devm_kcalloc(dev, 5, sizeof(struct attribute_group *),
+				   GFP_KERNEL);
+	if (!attr_groups)
+		return NULL;
+
+	attr_groups[0] = arm_cspmu_alloc_event_attr_group(cspmu);
+	attr_groups[1] = arm_cspmu_alloc_format_attr_group(cspmu);
+	attr_groups[2] = &arm_cspmu_identifier_attr_group;
+	attr_groups[3] = &arm_cspmu_cpumask_attr_group;
+
+	if (!attr_groups[0] || !attr_groups[1])
+		return NULL;
+
+	return attr_groups;
+}
+
+static inline void arm_cspmu_reset_counters(struct arm_cspmu *cspmu)
+{
+	u32 pmcr = 0;
+
+	pmcr |= PMCR_P;
+	pmcr |= PMCR_C;
+	writel(pmcr, cspmu->base0 + PMCR);
+}
+
+static inline void arm_cspmu_start_counters(struct arm_cspmu *cspmu)
+{
+	writel(PMCR_E, cspmu->base0 + PMCR);
+}
+
+static inline void arm_cspmu_stop_counters(struct arm_cspmu *cspmu)
+{
+	writel(0, cspmu->base0 + PMCR);
+}
+
+static void arm_cspmu_enable(struct pmu *pmu)
+{
+	bool disabled;
+	struct arm_cspmu *cspmu = to_arm_cspmu(pmu);
+
+	disabled = bitmap_empty(cspmu->hw_events.used_ctrs,
+				cspmu->num_logical_ctrs);
+
+	if (disabled)
+		return;
+
+	arm_cspmu_start_counters(cspmu);
+}
+
+static void arm_cspmu_disable(struct pmu *pmu)
+{
+	struct arm_cspmu *cspmu = to_arm_cspmu(pmu);
+
+	arm_cspmu_stop_counters(cspmu);
+}
+
+static int arm_cspmu_get_event_idx(struct arm_cspmu_hw_events *hw_events,
+				struct perf_event *event)
+{
+	int idx;
+	struct arm_cspmu *cspmu = to_arm_cspmu(event->pmu);
+
+	if (supports_cycle_counter(cspmu)) {
+		if (cspmu->impl.ops.is_cycle_counter_event(event)) {
+			/* Search for available cycle counter. */
+			if (test_and_set_bit(cspmu->cycle_counter_logical_idx,
+					     hw_events->used_ctrs))
+				return -EAGAIN;
+
+			return cspmu->cycle_counter_logical_idx;
+		}
+
+		/*
+		 * Search a regular counter from the used counter bitmap.
+		 * The cycle counter divides the bitmap into two parts. Search
+		 * the first then second half to exclude the cycle counter bit.
+		 */
+		idx = find_first_zero_bit(hw_events->used_ctrs,
+					  cspmu->cycle_counter_logical_idx);
+		if (idx >= cspmu->cycle_counter_logical_idx) {
+			idx = find_next_zero_bit(
+				hw_events->used_ctrs,
+				cspmu->num_logical_ctrs,
+				cspmu->cycle_counter_logical_idx + 1);
+		}
+	} else {
+		idx = find_first_zero_bit(hw_events->used_ctrs,
+					  cspmu->num_logical_ctrs);
+	}
+
+	if (idx >= cspmu->num_logical_ctrs)
+		return -EAGAIN;
+
+	set_bit(idx, hw_events->used_ctrs);
+
+	return idx;
+}
+
+static bool arm_cspmu_validate_event(struct pmu *pmu,
+				 struct arm_cspmu_hw_events *hw_events,
+				 struct perf_event *event)
+{
+	if (is_software_event(event))
+		return true;
+
+	/* Reject groups spanning multiple HW PMUs. */
+	if (event->pmu != pmu)
+		return false;
+
+	return (arm_cspmu_get_event_idx(hw_events, event) >= 0);
+}
+
+/*
+ * Make sure the group of events can be scheduled at once
+ * on the PMU.
+ */
+static bool arm_cspmu_validate_group(struct perf_event *event)
+{
+	struct perf_event *sibling, *leader = event->group_leader;
+	struct arm_cspmu_hw_events fake_hw_events;
+
+	if (event->group_leader == event)
+		return true;
+
+	memset(&fake_hw_events, 0, sizeof(fake_hw_events));
+
+	if (!arm_cspmu_validate_event(event->pmu, &fake_hw_events, leader))
+		return false;
+
+	for_each_sibling_event(sibling, leader) {
+		if (!arm_cspmu_validate_event(event->pmu, &fake_hw_events,
+						  sibling))
+			return false;
+	}
+
+	return arm_cspmu_validate_event(event->pmu, &fake_hw_events, event);
+}
+
+static int arm_cspmu_event_init(struct perf_event *event)
+{
+	struct arm_cspmu *cspmu;
+	struct hw_perf_event *hwc = &event->hw;
+
+	cspmu = to_arm_cspmu(event->pmu);
+
+	/*
+	 * Following other "uncore" PMUs, we do not support sampling mode or
+	 * attach to a task (per-process mode).
+	 */
+	if (is_sampling_event(event)) {
+		dev_dbg(cspmu->pmu.dev,
+			"Can't support sampling events\n");
+		return -EOPNOTSUPP;
+	}
+
+	if (event->cpu < 0 || event->attach_state & PERF_ATTACH_TASK) {
+		dev_dbg(cspmu->pmu.dev,
+			"Can't support per-task counters\n");
+		return -EINVAL;
+	}
+
+	/*
+	 * Make sure the CPU assignment is on one of the CPUs associated with
+	 * this PMU.
+	 */
+	if (!cpumask_test_cpu(event->cpu, &cspmu->associated_cpus)) {
+		dev_dbg(cspmu->pmu.dev,
+			"Requested cpu is not associated with the PMU\n");
+		return -EINVAL;
+	}
+
+	/* Enforce the current active CPU to handle the events in this PMU. */
+	event->cpu = cpumask_first(&cspmu->active_cpu);
+	if (event->cpu >= nr_cpu_ids)
+		return -EINVAL;
+
+	if (!arm_cspmu_validate_group(event))
+		return -EINVAL;
+
+	/*
+	 * The logical counter id is tracked with hw_perf_event.extra_reg.idx.
+	 * The physical counter id is tracked with hw_perf_event.idx.
+	 * We don't assign an index until we actually place the event onto
+	 * hardware. Use -1 to signify that we haven't decided where to put it
+	 * yet.
+	 */
+	hwc->idx = -1;
+	hwc->extra_reg.idx = -1;
+	hwc->config = cspmu->impl.ops.event_type(event);
+
+	return 0;
+}
+
+static inline u32 counter_offset(u32 reg_sz, u32 ctr_idx)
+{
+	return (PMEVCNTR_LO + (reg_sz * ctr_idx));
+}
+
+static void arm_cspmu_write_counter(struct perf_event *event, u64 val)
+{
+	u32 offset;
+	struct arm_cspmu *cspmu = to_arm_cspmu(event->pmu);
+
+	if (use_64b_counter_reg(cspmu)) {
+		offset = counter_offset(sizeof(u64), event->hw.idx);
+
+		writeq(val, cspmu->base1 + offset);
+	} else {
+		offset = counter_offset(sizeof(u32), event->hw.idx);
+
+		writel(lower_32_bits(val), cspmu->base1 + offset);
+	}
+}
+
+static u64 arm_cspmu_read_counter(struct perf_event *event)
+{
+	u32 offset;
+	const void __iomem *counter_addr;
+	struct arm_cspmu *cspmu = to_arm_cspmu(event->pmu);
+
+	if (use_64b_counter_reg(cspmu)) {
+		offset = counter_offset(sizeof(u64), event->hw.idx);
+		counter_addr = cspmu->base1 + offset;
+
+		return supports_64bit_atomics(cspmu) ?
+			       readq(counter_addr) :
+			       read_reg64_hilohi(counter_addr, HILOHI_MAX_POLL);
+	}
+
+	offset = counter_offset(sizeof(u32), event->hw.idx);
+	return readl(cspmu->base1 + offset);
+}
+
+/*
+ * arm_cspmu_set_event_period: Set the period for the counter.
+ *
+ * To handle cases of extreme interrupt latency, we program
+ * the counter with half of the max count for the counters.
+ */
+static void arm_cspmu_set_event_period(struct perf_event *event)
+{
+	struct arm_cspmu *cspmu = to_arm_cspmu(event->pmu);
+	u64 val = counter_mask(cspmu) >> 1ULL;
+
+	local64_set(&event->hw.prev_count, val);
+	arm_cspmu_write_counter(event, val);
+}
+
+static void arm_cspmu_enable_counter(struct arm_cspmu *cspmu, int idx)
+{
+	u32 reg_id, reg_bit, inten_off, cnten_off;
+
+	reg_id = COUNTER_TO_SET_CLR_ID(idx);
+	reg_bit = COUNTER_TO_SET_CLR_BIT(idx);
+
+	inten_off = PMINTENSET + (4 * reg_id);
+	cnten_off = PMCNTENSET + (4 * reg_id);
+
+	writel(BIT(reg_bit), cspmu->base0 + inten_off);
+	writel(BIT(reg_bit), cspmu->base0 + cnten_off);
+}
+
+static void arm_cspmu_disable_counter(struct arm_cspmu *cspmu, int idx)
+{
+	u32 reg_id, reg_bit, inten_off, cnten_off;
+
+	reg_id = COUNTER_TO_SET_CLR_ID(idx);
+	reg_bit = COUNTER_TO_SET_CLR_BIT(idx);
+
+	inten_off = PMINTENCLR + (4 * reg_id);
+	cnten_off = PMCNTENCLR + (4 * reg_id);
+
+	writel(BIT(reg_bit), cspmu->base0 + cnten_off);
+	writel(BIT(reg_bit), cspmu->base0 + inten_off);
+}
+
+static void arm_cspmu_event_update(struct perf_event *event)
+{
+	struct arm_cspmu *cspmu = to_arm_cspmu(event->pmu);
+	struct hw_perf_event *hwc = &event->hw;
+	u64 delta, prev, now;
+
+	do {
+		prev = local64_read(&hwc->prev_count);
+		now = arm_cspmu_read_counter(event);
+	} while (local64_cmpxchg(&hwc->prev_count, prev, now) != prev);
+
+	delta = (now - prev) & counter_mask(cspmu);
+	local64_add(delta, &event->count);
+}
+
+static inline void arm_cspmu_set_event(struct arm_cspmu *cspmu,
+					struct hw_perf_event *hwc)
+{
+	u32 offset = PMEVTYPER + (4 * hwc->idx);
+
+	writel(hwc->config, cspmu->base0 + offset);
+}
+
+static inline void arm_cspmu_set_ev_filter(struct arm_cspmu *cspmu,
+					   struct hw_perf_event *hwc,
+					   u32 filter)
+{
+	u32 offset = PMEVFILTR + (4 * hwc->idx);
+
+	writel(filter, cspmu->base0 + offset);
+}
+
+static inline void arm_cspmu_set_cc_filter(struct arm_cspmu *cspmu, u32 filter)
+{
+	u32 offset = PMCCFILTR;
+
+	writel(filter, cspmu->base0 + offset);
+}
+
+static void arm_cspmu_start(struct perf_event *event, int pmu_flags)
+{
+	struct arm_cspmu *cspmu = to_arm_cspmu(event->pmu);
+	struct hw_perf_event *hwc = &event->hw;
+	u32 filter;
+
+	/* We always reprogram the counter */
+	if (pmu_flags & PERF_EF_RELOAD)
+		WARN_ON(!(hwc->state & PERF_HES_UPTODATE));
+
+	arm_cspmu_set_event_period(event);
+
+	filter = cspmu->impl.ops.event_filter(event);
+
+	if (event->hw.extra_reg.idx == cspmu->cycle_counter_logical_idx) {
+		arm_cspmu_set_cc_filter(cspmu, filter);
+	} else {
+		arm_cspmu_set_event(cspmu, hwc);
+		arm_cspmu_set_ev_filter(cspmu, hwc, filter);
+	}
+
+	hwc->state = 0;
+
+	arm_cspmu_enable_counter(cspmu, hwc->idx);
+}
+
+static void arm_cspmu_stop(struct perf_event *event, int pmu_flags)
+{
+	struct arm_cspmu *cspmu = to_arm_cspmu(event->pmu);
+	struct hw_perf_event *hwc = &event->hw;
+
+	if (hwc->state & PERF_HES_STOPPED)
+		return;
+
+	arm_cspmu_disable_counter(cspmu, hwc->idx);
+	arm_cspmu_event_update(event);
+
+	hwc->state |= PERF_HES_STOPPED | PERF_HES_UPTODATE;
+}
+
+static inline u32 to_phys_idx(struct arm_cspmu *cspmu, u32 idx)
+{
+	return (idx == cspmu->cycle_counter_logical_idx) ?
+		ARM_CSPMU_CYCLE_CNTR_IDX : idx;
+}
+
+static int arm_cspmu_add(struct perf_event *event, int flags)
+{
+	struct arm_cspmu *cspmu = to_arm_cspmu(event->pmu);
+	struct arm_cspmu_hw_events *hw_events = &cspmu->hw_events;
+	struct hw_perf_event *hwc = &event->hw;
+	int idx;
+
+	if (WARN_ON_ONCE(!cpumask_test_cpu(smp_processor_id(),
+					   &cspmu->associated_cpus)))
+		return -ENOENT;
+
+	idx = arm_cspmu_get_event_idx(hw_events, event);
+	if (idx < 0)
+		return idx;
+
+	hw_events->events[idx] = event;
+	hwc->idx = to_phys_idx(cspmu, idx);
+	hwc->extra_reg.idx = idx;
+	hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE;
+
+	if (flags & PERF_EF_START)
+		arm_cspmu_start(event, PERF_EF_RELOAD);
+
+	/* Propagate changes to the userspace mapping. */
+	perf_event_update_userpage(event);
+
+	return 0;
+}
+
+static void arm_cspmu_del(struct perf_event *event, int flags)
+{
+	struct arm_cspmu *cspmu = to_arm_cspmu(event->pmu);
+	struct arm_cspmu_hw_events *hw_events = &cspmu->hw_events;
+	struct hw_perf_event *hwc = &event->hw;
+	int idx = hwc->extra_reg.idx;
+
+	arm_cspmu_stop(event, PERF_EF_UPDATE);
+
+	hw_events->events[idx] = NULL;
+
+	clear_bit(idx, hw_events->used_ctrs);
+
+	perf_event_update_userpage(event);
+}
+
+static void arm_cspmu_read(struct perf_event *event)
+{
+	arm_cspmu_event_update(event);
+}
+
+static struct arm_cspmu *arm_cspmu_alloc(struct platform_device *pdev)
+{
+	struct acpi_apmt_node *apmt_node;
+	struct arm_cspmu *cspmu;
+	struct device *dev;
+
+	dev = &pdev->dev;
+	apmt_node = *(struct acpi_apmt_node **)dev_get_platdata(dev);
+	if (!apmt_node) {
+		dev_err(dev, "failed to get APMT node\n");
+		return NULL;
+	}
+
+	cspmu = devm_kzalloc(dev, sizeof(*cspmu), GFP_KERNEL);
+	if (!cspmu)
+		return NULL;
+
+	cspmu->dev = dev;
+	cspmu->apmt_node = apmt_node;
+
+	platform_set_drvdata(pdev, cspmu);
+
+	return cspmu;
+}
+
+static int arm_cspmu_init_mmio(struct arm_cspmu *cspmu)
+{
+	struct device *dev;
+	struct platform_device *pdev;
+	struct acpi_apmt_node *apmt_node;
+
+	dev = cspmu->dev;
+	pdev = to_platform_device(dev);
+	apmt_node = cspmu->apmt_node;
+
+	/* Base address for page 0. */
+	cspmu->base0 = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(cspmu->base0)) {
+		dev_err(dev, "ioremap failed for page-0 resource\n");
+		return PTR_ERR(cspmu->base0);
+	}
+
+	/* Base address for page 1 if supported. Otherwise point to page 0. */
+	cspmu->base1 = cspmu->base0;
+	if (CHECK_APMT_FLAG(apmt_node->flags, DUAL_PAGE, SUPP)) {
+		cspmu->base1 = devm_platform_ioremap_resource(pdev, 1);
+		if (IS_ERR(cspmu->base1)) {
+			dev_err(dev, "ioremap failed for page-1 resource\n");
+			return PTR_ERR(cspmu->base1);
+		}
+	}
+
+	cspmu->pmcfgr = readl(cspmu->base0 + PMCFGR);
+
+	cspmu->num_logical_ctrs = FIELD_GET(PMCFGR_N, cspmu->pmcfgr) + 1;
+
+	cspmu->cycle_counter_logical_idx = ARM_CSPMU_MAX_HW_CNTRS;
+
+	if (supports_cycle_counter(cspmu)) {
+		/*
+		 * The last logical counter is mapped to cycle counter if
+		 * there is a gap between regular and cycle counter. Otherwise,
+		 * logical and physical have 1-to-1 mapping.
+		 */
+		cspmu->cycle_counter_logical_idx =
+			(cspmu->num_logical_ctrs <= ARM_CSPMU_CYCLE_CNTR_IDX) ?
+				cspmu->num_logical_ctrs - 1 :
+				ARM_CSPMU_CYCLE_CNTR_IDX;
+	}
+
+	cspmu->num_set_clr_reg =
+		DIV_ROUND_UP(cspmu->num_logical_ctrs,
+				ARM_CSPMU_SET_CLR_COUNTER_NUM);
+
+	cspmu->hw_events.events =
+		devm_kcalloc(dev, cspmu->num_logical_ctrs,
+			     sizeof(*cspmu->hw_events.events), GFP_KERNEL);
+
+	if (!cspmu->hw_events.events)
+		return -ENOMEM;
+
+	return 0;
+}
+
+static inline int arm_cspmu_get_reset_overflow(struct arm_cspmu *cspmu,
+					       u32 *pmovs)
+{
+	int i;
+	u32 pmovclr_offset = PMOVSCLR;
+	u32 has_overflowed = 0;
+
+	for (i = 0; i < cspmu->num_set_clr_reg; ++i) {
+		pmovs[i] = readl(cspmu->base1 + pmovclr_offset);
+		has_overflowed |= pmovs[i];
+		writel(pmovs[i], cspmu->base1 + pmovclr_offset);
+		pmovclr_offset += sizeof(u32);
+	}
+
+	return has_overflowed != 0;
+}
+
+static irqreturn_t arm_cspmu_handle_irq(int irq_num, void *dev)
+{
+	int idx, has_overflowed;
+	struct perf_event *event;
+	struct arm_cspmu *cspmu = dev;
+	DECLARE_BITMAP(pmovs, ARM_CSPMU_MAX_HW_CNTRS);
+	bool handled = false;
+
+	arm_cspmu_stop_counters(cspmu);
+
+	has_overflowed = arm_cspmu_get_reset_overflow(cspmu, (u32 *)pmovs);
+	if (!has_overflowed)
+		goto done;
+
+	for_each_set_bit(idx, cspmu->hw_events.used_ctrs,
+			cspmu->num_logical_ctrs) {
+		event = cspmu->hw_events.events[idx];
+
+		if (!event)
+			continue;
+
+		if (!test_bit(event->hw.idx, pmovs))
+			continue;
+
+		arm_cspmu_event_update(event);
+		arm_cspmu_set_event_period(event);
+
+		handled = true;
+	}
+
+done:
+	arm_cspmu_start_counters(cspmu);
+	return IRQ_RETVAL(handled);
+}
+
+static int arm_cspmu_request_irq(struct arm_cspmu *cspmu)
+{
+	int irq, ret;
+	struct device *dev;
+	struct platform_device *pdev;
+	struct acpi_apmt_node *apmt_node;
+
+	dev = cspmu->dev;
+	pdev = to_platform_device(dev);
+	apmt_node = cspmu->apmt_node;
+
+	/* Skip IRQ request if the PMU does not support overflow interrupt. */
+	if (apmt_node->ovflw_irq == 0)
+		return 0;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0)
+		return irq;
+
+	ret = devm_request_irq(dev, irq, arm_cspmu_handle_irq,
+			       IRQF_NOBALANCING | IRQF_NO_THREAD, dev_name(dev),
+			       cspmu);
+	if (ret) {
+		dev_err(dev, "Could not request IRQ %d\n", irq);
+		return ret;
+	}
+
+	cspmu->irq = irq;
+
+	return 0;
+}
+
+static inline int arm_cspmu_find_cpu_container(int cpu, u32 container_uid)
+{
+	u32 acpi_uid;
+	struct device *cpu_dev = get_cpu_device(cpu);
+	struct acpi_device *acpi_dev = ACPI_COMPANION(cpu_dev);
+
+	if (!cpu_dev)
+		return -ENODEV;
+
+	while (acpi_dev) {
+		if (!strcmp(acpi_device_hid(acpi_dev),
+			    ACPI_PROCESSOR_CONTAINER_HID) &&
+		    !kstrtouint(acpi_device_uid(acpi_dev), 0, &acpi_uid) &&
+		    acpi_uid == container_uid)
+			return 0;
+
+		acpi_dev = acpi_dev_parent(acpi_dev);
+	}
+
+	return -ENODEV;
+}
+
+static int arm_cspmu_get_cpus(struct arm_cspmu *cspmu)
+{
+	struct device *dev;
+	struct acpi_apmt_node *apmt_node;
+	int affinity_flag;
+	int cpu;
+
+	dev = cspmu->pmu.dev;
+	apmt_node = cspmu->apmt_node;
+	affinity_flag = apmt_node->flags & ACPI_APMT_FLAGS_AFFINITY;
+
+	if (affinity_flag == ACPI_APMT_FLAGS_AFFINITY_PROC) {
+		for_each_possible_cpu(cpu) {
+			if (apmt_node->proc_affinity ==
+			    get_acpi_id_for_cpu(cpu)) {
+				cpumask_set_cpu(cpu, &cspmu->associated_cpus);
+				break;
+			}
+		}
+	} else {
+		for_each_possible_cpu(cpu) {
+			if (arm_cspmu_find_cpu_container(
+				    cpu, apmt_node->proc_affinity))
+				continue;
+
+			cpumask_set_cpu(cpu, &cspmu->associated_cpus);
+		}
+	}
+
+	if (cpumask_empty(&cspmu->associated_cpus)) {
+		dev_dbg(dev, "No cpu associated with the PMU\n");
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+static int arm_cspmu_register_pmu(struct arm_cspmu *cspmu)
+{
+	int ret, capabilities;
+	struct attribute_group **attr_groups;
+
+	attr_groups = arm_cspmu_alloc_attr_group(cspmu);
+	if (!attr_groups)
+		return -ENOMEM;
+
+	ret = cpuhp_state_add_instance(arm_cspmu_cpuhp_state,
+				       &cspmu->cpuhp_node);
+	if (ret)
+		return ret;
+
+	capabilities = PERF_PMU_CAP_NO_EXCLUDE;
+	if (cspmu->irq == 0)
+		capabilities |= PERF_PMU_CAP_NO_INTERRUPT;
+
+	cspmu->pmu = (struct pmu){
+		.task_ctx_nr	= perf_invalid_context,
+		.module		= THIS_MODULE,
+		.pmu_enable	= arm_cspmu_enable,
+		.pmu_disable	= arm_cspmu_disable,
+		.event_init	= arm_cspmu_event_init,
+		.add		= arm_cspmu_add,
+		.del		= arm_cspmu_del,
+		.start		= arm_cspmu_start,
+		.stop		= arm_cspmu_stop,
+		.read		= arm_cspmu_read,
+		.attr_groups	= (const struct attribute_group **)attr_groups,
+		.capabilities	= capabilities,
+	};
+
+	/* Hardware counter init */
+	arm_cspmu_stop_counters(cspmu);
+	arm_cspmu_reset_counters(cspmu);
+
+	ret = perf_pmu_register(&cspmu->pmu, cspmu->name, -1);
+	if (ret) {
+		cpuhp_state_remove_instance(arm_cspmu_cpuhp_state,
+					    &cspmu->cpuhp_node);
+	}
+
+	return ret;
+}
+
+static int arm_cspmu_device_probe(struct platform_device *pdev)
+{
+	int ret;
+	struct arm_cspmu *cspmu;
+
+	cspmu = arm_cspmu_alloc(pdev);
+	if (!cspmu)
+		return -ENOMEM;
+
+	ret = arm_cspmu_init_mmio(cspmu);
+	if (ret)
+		return ret;
+
+	ret = arm_cspmu_request_irq(cspmu);
+	if (ret)
+		return ret;
+
+	ret = arm_cspmu_get_cpus(cspmu);
+	if (ret)
+		return ret;
+
+	ret = arm_cspmu_register_pmu(cspmu);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static int arm_cspmu_device_remove(struct platform_device *pdev)
+{
+	struct arm_cspmu *cspmu = platform_get_drvdata(pdev);
+
+	perf_pmu_unregister(&cspmu->pmu);
+	cpuhp_state_remove_instance(arm_cspmu_cpuhp_state, &cspmu->cpuhp_node);
+
+	return 0;
+}
+
+static struct platform_driver arm_cspmu_driver = {
+	.driver = {
+			.name = DRVNAME,
+			.suppress_bind_attrs = true,
+		},
+	.probe = arm_cspmu_device_probe,
+	.remove = arm_cspmu_device_remove,
+};
+
+static void arm_cspmu_set_active_cpu(int cpu, struct arm_cspmu *cspmu)
+{
+	cpumask_set_cpu(cpu, &cspmu->active_cpu);
+	WARN_ON(irq_set_affinity(cspmu->irq, &cspmu->active_cpu));
+}
+
+static int arm_cspmu_cpu_online(unsigned int cpu, struct hlist_node *node)
+{
+	struct arm_cspmu *cspmu =
+		hlist_entry_safe(node, struct arm_cspmu, cpuhp_node);
+
+	if (!cpumask_test_cpu(cpu, &cspmu->associated_cpus))
+		return 0;
+
+	/* If the PMU is already managed, there is nothing to do */
+	if (!cpumask_empty(&cspmu->active_cpu))
+		return 0;
+
+	/* Use this CPU for event counting */
+	arm_cspmu_set_active_cpu(cpu, cspmu);
+
+	return 0;
+}
+
+static int arm_cspmu_cpu_teardown(unsigned int cpu, struct hlist_node *node)
+{
+	int dst;
+	struct cpumask online_supported;
+
+	struct arm_cspmu *cspmu =
+		hlist_entry_safe(node, struct arm_cspmu, cpuhp_node);
+
+	/* Nothing to do if this CPU doesn't own the PMU */
+	if (!cpumask_test_and_clear_cpu(cpu, &cspmu->active_cpu))
+		return 0;
+
+	/* Choose a new CPU to migrate ownership of the PMU to */
+	cpumask_and(&online_supported, &cspmu->associated_cpus,
+		    cpu_online_mask);
+	dst = cpumask_any_but(&online_supported, cpu);
+	if (dst >= nr_cpu_ids)
+		return 0;
+
+	/* Use this CPU for event counting */
+	perf_pmu_migrate_context(&cspmu->pmu, cpu, dst);
+	arm_cspmu_set_active_cpu(dst, cspmu);
+
+	return 0;
+}
+
+static int __init arm_cspmu_init(void)
+{
+	int ret;
+
+	ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN,
+					"perf/arm/cspmu:online",
+					arm_cspmu_cpu_online,
+					arm_cspmu_cpu_teardown);
+	if (ret < 0)
+		return ret;
+	arm_cspmu_cpuhp_state = ret;
+	return platform_driver_register(&arm_cspmu_driver);
+}
+
+static void __exit arm_cspmu_exit(void)
+{
+	platform_driver_unregister(&arm_cspmu_driver);
+	cpuhp_remove_multi_state(arm_cspmu_cpuhp_state);
+}
+
+module_init(arm_cspmu_init);
+module_exit(arm_cspmu_exit);
+
+MODULE_LICENSE("GPL v2");