perf: RISC-V: Add support for SBI PMU and Sscofpmf

This series improves perf support for RISC-V based system using SBI PMU
and Sscofpmf extensions, by adding a new generic RISC-V perf framework
along with a pair of drivers: one that usese the new
performance-monitoring extensions and one that keeps support for the
existing systems that only have the legacy counters.

Tested-by: Nikita Shubin <n.shubin@yadro.com>

* palmer/riscv-pmu:
  MAINTAINERS: Add entry for RISC-V PMU drivers
  Documentation: riscv: Remove the old documentation
  RISC-V: Add sscofpmf extension support
  RISC-V: Add perf platform driver based on SBI PMU extension
  RISC-V: Add RISC-V SBI PMU extension definitions
  RISC-V: Add a simple platform driver for RISC-V legacy perf
  RISC-V: Add a perf core library for pmu drivers
  RISC-V: Add CSR encodings for all HPMCOUNTERS
  RISC-V: Remove the current perf implementation

18 files changed, 1538 insertions, 827 deletions

diff --git a/Documentation/riscv/pmu.rst b/Documentation/riscv/pmu.rst
deleted file mode 100644
index acb216b99c26..000000000000
--- a/Documentation/riscv/pmu.rst
+++ /dev/null
@@ -1,255 +0,0 @@
-===================================
-Supporting PMUs on RISC-V platforms
-===================================
-
-Alan Kao <alankao@andestech.com>, Mar 2018
-
-Introduction
-------------
-
-As of this writing, perf_event-related features mentioned in The RISC-V ISA
-Privileged Version 1.10 are as follows:
-(please check the manual for more details)
-
-* [m|s]counteren
-* mcycle[h], cycle[h]
-* minstret[h], instret[h]
-* mhpeventx, mhpcounterx[h]
-
-With such function set only, porting perf would require a lot of work, due to
-the lack of the following general architectural performance monitoring features:
-
-* Enabling/Disabling counters
-  Counters are just free-running all the time in our case.
-* Interrupt caused by counter overflow
-  No such feature in the spec.
-* Interrupt indicator
-  It is not possible to have many interrupt ports for all counters, so an
-  interrupt indicator is required for software to tell which counter has
-  just overflowed.
-* Writing to counters
-  There will be an SBI to support this since the kernel cannot modify the
-  counters [1].  Alternatively, some vendor considers to implement
-  hardware-extension for M-S-U model machines to write counters directly.
-
-This document aims to provide developers a quick guide on supporting their
-PMUs in the kernel.  The following sections briefly explain perf' mechanism
-and todos.
-
-You may check previous discussions here [1][2].  Also, it might be helpful
-to check the appendix for related kernel structures.
-
-
-1. Initialization
------------------
-
-*riscv_pmu* is a global pointer of type *struct riscv_pmu*, which contains
-various methods according to perf's internal convention and PMU-specific
-parameters.  One should declare such instance to represent the PMU.  By default,
-*riscv_pmu* points to a constant structure *riscv_base_pmu*, which has very
-basic support to a baseline QEMU model.
-
-Then he/she can either assign the instance's pointer to *riscv_pmu* so that
-the minimal and already-implemented logic can be leveraged, or invent his/her
-own *riscv_init_platform_pmu* implementation.
-
-In other words, existing sources of *riscv_base_pmu* merely provide a
-reference implementation.  Developers can flexibly decide how many parts they
-can leverage, and in the most extreme case, they can customize every function
-according to their needs.
-
-
-2. Event Initialization
------------------------
-
-When a user launches a perf command to monitor some events, it is first
-interpreted by the userspace perf tool into multiple *perf_event_open*
-system calls, and then each of them calls to the body of *event_init*
-member function that was assigned in the previous step.  In *riscv_base_pmu*'s
-case, it is *riscv_event_init*.
-
-The main purpose of this function is to translate the event provided by user
-into bitmap, so that HW-related control registers or counters can directly be
-manipulated.  The translation is based on the mappings and methods provided in
-*riscv_pmu*.
-
-Note that some features can be done in this stage as well:
-
-(1) interrupt setting, which is stated in the next section;
-(2) privilege level setting (user space only, kernel space only, both);
-(3) destructor setting.  Normally it is sufficient to apply *riscv_destroy_event*;
-(4) tweaks for non-sampling events, which will be utilized by functions such as
-    *perf_adjust_period*, usually something like the follows::
-
-      if (!is_sampling_event(event)) {
-              hwc->sample_period = x86_pmu.max_period;
-              hwc->last_period = hwc->sample_period;
-              local64_set(&hwc->period_left, hwc->sample_period);
-      }
-
-In the case of *riscv_base_pmu*, only (3) is provided for now.
-
-
-3. Interrupt
-------------
-
-3.1. Interrupt Initialization
-
-This often occurs at the beginning of the *event_init* method. In common
-practice, this should be a code segment like::
-
-  int x86_reserve_hardware(void)
-  {
-        int err = 0;
-
-        if (!atomic_inc_not_zero(&pmc_refcount)) {
-                mutex_lock(&pmc_reserve_mutex);
-                if (atomic_read(&pmc_refcount) == 0) {
-                        if (!reserve_pmc_hardware())
-                                err = -EBUSY;
-                        else
-                                reserve_ds_buffers();
-                }
-                if (!err)
-                        atomic_inc(&pmc_refcount);
-                mutex_unlock(&pmc_reserve_mutex);
-        }
-
-        return err;
-  }
-
-And the magic is in *reserve_pmc_hardware*, which usually does atomic
-operations to make implemented IRQ accessible from some global function pointer.
-*release_pmc_hardware* serves the opposite purpose, and it is used in event
-destructors mentioned in previous section.
-
-(Note: From the implementations in all the architectures, the *reserve/release*
-pair are always IRQ settings, so the *pmc_hardware* seems somehow misleading.
-It does NOT deal with the binding between an event and a physical counter,
-which will be introduced in the next section.)
-
-3.2. IRQ Structure
-
-Basically, a IRQ runs the following pseudo code::
-
-  for each hardware counter that triggered this overflow
-
-      get the event of this counter
-
-      // following two steps are defined as *read()*,
-      // check the section Reading/Writing Counters for details.
-      count the delta value since previous interrupt
-      update the event->count (# event occurs) by adding delta, and
-                 event->hw.period_left by subtracting delta
-
-      if the event overflows
-          sample data
-          set the counter appropriately for the next overflow
-
-          if the event overflows again
-              too frequently, throttle this event
-          fi
-      fi
-
-  end for
-
-However as of this writing, none of the RISC-V implementations have designed an
-interrupt for perf, so the details are to be completed in the future.
-
-4. Reading/Writing Counters
----------------------------
-
-They seem symmetric but perf treats them quite differently.  For reading, there
-is a *read* interface in *struct pmu*, but it serves more than just reading.
-According to the context, the *read* function not only reads the content of the
-counter (event->count), but also updates the left period to the next interrupt
-(event->hw.period_left).
-
-But the core of perf does not need direct write to counters.  Writing counters
-is hidden behind the abstraction of 1) *pmu->start*, literally start counting so one
-has to set the counter to a good value for the next interrupt; 2) inside the IRQ
-it should set the counter to the same resonable value.
-
-Reading is not a problem in RISC-V but writing would need some effort, since
-counters are not allowed to be written by S-mode.
-
-
-5. add()/del()/start()/stop()
------------------------------
-
-Basic idea: add()/del() adds/deletes events to/from a PMU, and start()/stop()
-starts/stop the counter of some event in the PMU.  All of them take the same
-arguments: *struct perf_event *event* and *int flag*.
-
-Consider perf as a state machine, then you will find that these functions serve
-as the state transition process between those states.
-Three states (event->hw.state) are defined:
-
-* PERF_HES_STOPPED:	the counter is stopped
-* PERF_HES_UPTODATE:	the event->count is up-to-date
-* PERF_HES_ARCH:	arch-dependent usage ... we don't need this for now
-
-A normal flow of these state transitions are as follows:
-
-* A user launches a perf event, resulting in calling to *event_init*.
-* When being context-switched in, *add* is called by the perf core, with a flag
-  PERF_EF_START, which means that the event should be started after it is added.
-  At this stage, a general event is bound to a physical counter, if any.
-  The state changes to PERF_HES_STOPPED and PERF_HES_UPTODATE, because it is now
-  stopped, and the (software) event count does not need updating.
-
-  - *start* is then called, and the counter is enabled.
-    With flag PERF_EF_RELOAD, it writes an appropriate value to the counter (check
-    previous section for detail).
-    Nothing is written if the flag does not contain PERF_EF_RELOAD.
-    The state now is reset to none, because it is neither stopped nor updated
-    (the counting already started)
-
-* When being context-switched out, *del* is called.  It then checks out all the
-  events in the PMU and calls *stop* to update their counts.
-
-  - *stop* is called by *del*
-    and the perf core with flag PERF_EF_UPDATE, and it often shares the same
-    subroutine as *read* with the same logic.
-    The state changes to PERF_HES_STOPPED and PERF_HES_UPTODATE, again.
-
-  - Life cycle of these two pairs: *add* and *del* are called repeatedly as
-    tasks switch in-and-out; *start* and *stop* is also called when the perf core
-    needs a quick stop-and-start, for instance, when the interrupt period is being
-    adjusted.
-
-Current implementation is sufficient for now and can be easily extended to
-features in the future.
-
-A. Related Structures
----------------------
-
-* struct pmu: include/linux/perf_event.h
-* struct riscv_pmu: arch/riscv/include/asm/perf_event.h
-
-  Both structures are designed to be read-only.
-
-  *struct pmu* defines some function pointer interfaces, and most of them take
-  *struct perf_event* as a main argument, dealing with perf events according to
-  perf's internal state machine (check kernel/events/core.c for details).
-
-  *struct riscv_pmu* defines PMU-specific parameters.  The naming follows the
-  convention of all other architectures.
-
-* struct perf_event: include/linux/perf_event.h
-* struct hw_perf_event
-
-  The generic structure that represents perf events, and the hardware-related
-  details.
-
-* struct riscv_hw_events: arch/riscv/include/asm/perf_event.h
-
-  The structure that holds the status of events, has two fixed members:
-  the number of events and the array of the events.
-
-References
-----------
-
-[1] https://github.com/riscv/riscv-linux/pull/124
-
-[2] https://groups.google.com/a/groups.riscv.org/forum/#!topic/sw-dev/f19TmCNP6yA
diff --git a/MAINTAINERS b/MAINTAINERS
index 779a550dc95b..e4c3f7507665 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -16561,6 +16561,15 @@ S:	Maintained
 F:	drivers/mtd/nand/raw/r852.c
 F:	drivers/mtd/nand/raw/r852.h
 
+RISC-V PMU DRIVERS
+M:	Atish Patra <atishp@atishpatra.org>
+R:	Anup Patel <anup@brainfault.org>
+L:	linux-riscv@lists.infradead.org
+S:	Supported
+F:	drivers/perf/riscv_pmu.c
+F:	drivers/perf/riscv_pmu_legacy.c
+F:	drivers/perf/riscv_pmu_sbi.c
+
 RISC-V ARCHITECTURE
 M:	Paul Walmsley <paul.walmsley@sifive.com>
 M:	Palmer Dabbelt <palmer@dabbelt.com>
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index 81682a152800..339ba6f6580d 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -333,19 +333,6 @@ config RISCV_ISA_C
 
 	   If you don't know what to do here, say Y.
 
-menu "supported PMU type"
-	depends on PERF_EVENTS
-
-config RISCV_BASE_PMU
-	bool "Base Performance Monitoring Unit"
-	def_bool y
-	help
-	  A base PMU that serves as a reference implementation and has limited
-	  feature of perf.  It can run on any RISC-V machines so serves as the
-	  fallback, but this option can also be disable to reduce kernel size.
-
-endmenu
-
 config FPU
 	bool "FPU support"
 	default y
diff --git a/arch/riscv/include/asm/csr.h b/arch/riscv/include/asm/csr.h
index 299abdef0cd6..e935f27b10fd 100644
--- a/arch/riscv/include/asm/csr.h
+++ b/arch/riscv/include/asm/csr.h
@@ -66,6 +66,7 @@
 #define IRQ_S_EXT		9
 #define IRQ_VS_EXT		10
 #define IRQ_M_EXT		11
+#define IRQ_PMU_OVF		13
 
 /* Exception causes */
 #define EXC_INST_MISALIGNED	0
@@ -151,9 +152,69 @@
 #define CSR_CYCLE		0xc00
 #define CSR_TIME		0xc01
 #define CSR_INSTRET		0xc02
+#define CSR_HPMCOUNTER3		0xc03
+#define CSR_HPMCOUNTER4		0xc04
+#define CSR_HPMCOUNTER5		0xc05
+#define CSR_HPMCOUNTER6		0xc06
+#define CSR_HPMCOUNTER7		0xc07
+#define CSR_HPMCOUNTER8		0xc08
+#define CSR_HPMCOUNTER9		0xc09
+#define CSR_HPMCOUNTER10	0xc0a
+#define CSR_HPMCOUNTER11	0xc0b
+#define CSR_HPMCOUNTER12	0xc0c
+#define CSR_HPMCOUNTER13	0xc0d
+#define CSR_HPMCOUNTER14	0xc0e
+#define CSR_HPMCOUNTER15	0xc0f
+#define CSR_HPMCOUNTER16	0xc10
+#define CSR_HPMCOUNTER17	0xc11
+#define CSR_HPMCOUNTER18	0xc12
+#define CSR_HPMCOUNTER19	0xc13
+#define CSR_HPMCOUNTER20	0xc14
+#define CSR_HPMCOUNTER21	0xc15
+#define CSR_HPMCOUNTER22	0xc16
+#define CSR_HPMCOUNTER23	0xc17
+#define CSR_HPMCOUNTER24	0xc18
+#define CSR_HPMCOUNTER25	0xc19
+#define CSR_HPMCOUNTER26	0xc1a
+#define CSR_HPMCOUNTER27	0xc1b
+#define CSR_HPMCOUNTER28	0xc1c
+#define CSR_HPMCOUNTER29	0xc1d
+#define CSR_HPMCOUNTER30	0xc1e
+#define CSR_HPMCOUNTER31	0xc1f
 #define CSR_CYCLEH		0xc80
 #define CSR_TIMEH		0xc81
 #define CSR_INSTRETH		0xc82
+#define CSR_HPMCOUNTER3H	0xc83
+#define CSR_HPMCOUNTER4H	0xc84
+#define CSR_HPMCOUNTER5H	0xc85
+#define CSR_HPMCOUNTER6H	0xc86
+#define CSR_HPMCOUNTER7H	0xc87
+#define CSR_HPMCOUNTER8H	0xc88
+#define CSR_HPMCOUNTER9H	0xc89
+#define CSR_HPMCOUNTER10H	0xc8a
+#define CSR_HPMCOUNTER11H	0xc8b
+#define CSR_HPMCOUNTER12H	0xc8c
+#define CSR_HPMCOUNTER13H	0xc8d
+#define CSR_HPMCOUNTER14H	0xc8e
+#define CSR_HPMCOUNTER15H	0xc8f
+#define CSR_HPMCOUNTER16H	0xc90
+#define CSR_HPMCOUNTER17H	0xc91
+#define CSR_HPMCOUNTER18H	0xc92
+#define CSR_HPMCOUNTER19H	0xc93
+#define CSR_HPMCOUNTER20H	0xc94
+#define CSR_HPMCOUNTER21H	0xc95
+#define CSR_HPMCOUNTER22H	0xc96
+#define CSR_HPMCOUNTER23H	0xc97
+#define CSR_HPMCOUNTER24H	0xc98
+#define CSR_HPMCOUNTER25H	0xc99
+#define CSR_HPMCOUNTER26H	0xc9a
+#define CSR_HPMCOUNTER27H	0xc9b
+#define CSR_HPMCOUNTER28H	0xc9c
+#define CSR_HPMCOUNTER29H	0xc9d
+#define CSR_HPMCOUNTER30H	0xc9e
+#define CSR_HPMCOUNTER31H	0xc9f
+
+#define CSR_SSCOUNTOVF		0xda0
 
 #define CSR_SSTATUS		0x100
 #define CSR_SIE			0x104
@@ -241,7 +302,10 @@
 # define RV_IRQ_SOFT		IRQ_S_SOFT
 # define RV_IRQ_TIMER	IRQ_S_TIMER
 # define RV_IRQ_EXT		IRQ_S_EXT
-#endif /* CONFIG_RISCV_M_MODE */
+# define RV_IRQ_PMU	IRQ_PMU_OVF
+# define SIP_LCOFIP     (_AC(0x1, UL) << IRQ_PMU_OVF)
+
+#endif /* !CONFIG_RISCV_M_MODE */
 
 /* IE/IP (Supervisor/Machine Interrupt Enable/Pending) flags */
 #define IE_SIE		(_AC(0x1, UL) << RV_IRQ_SOFT)
diff --git a/arch/riscv/include/asm/hwcap.h b/arch/riscv/include/asm/hwcap.h
index 691fc9c8099b..0734e42f74f2 100644
--- a/arch/riscv/include/asm/hwcap.h
+++ b/arch/riscv/include/asm/hwcap.h
@@ -51,6 +51,7 @@ extern unsigned long elf_hwcap;
  * available logical extension id.
  */
 enum riscv_isa_ext_id {
+	RISCV_ISA_EXT_SSCOFPMF = RISCV_ISA_EXT_BASE,
 	RISCV_ISA_EXT_ID_MAX = RISCV_ISA_EXT_MAX,
 };
 
diff --git a/arch/riscv/include/asm/perf_event.h b/arch/riscv/include/asm/perf_event.h
index 062efd3a1d5d..d42c901f9a97 100644
--- a/arch/riscv/include/asm/perf_event.h
+++ b/arch/riscv/include/asm/perf_event.h
@@ -9,77 +9,5 @@
 #define _ASM_RISCV_PERF_EVENT_H
 
 #include <linux/perf_event.h>
-#include <linux/ptrace.h>
-#include <linux/interrupt.h>
-
-#ifdef CONFIG_RISCV_BASE_PMU
-#define RISCV_BASE_COUNTERS	2
-
-/*
- * The RISCV_MAX_COUNTERS parameter should be specified.
- */
-
-#define RISCV_MAX_COUNTERS	2
-
-/*
- * These are the indexes of bits in counteren register *minus* 1,
- * except for cycle.  It would be coherent if it can directly mapped
- * to counteren bit definition, but there is a *time* register at
- * counteren[1].  Per-cpu structure is scarce resource here.
- *
- * According to the spec, an implementation can support counter up to
- * mhpmcounter31, but many high-end processors has at most 6 general
- * PMCs, we give the definition to MHPMCOUNTER8 here.
- */
-#define RISCV_PMU_CYCLE		0
-#define RISCV_PMU_INSTRET	1
-#define RISCV_PMU_MHPMCOUNTER3	2
-#define RISCV_PMU_MHPMCOUNTER4	3
-#define RISCV_PMU_MHPMCOUNTER5	4
-#define RISCV_PMU_MHPMCOUNTER6	5
-#define RISCV_PMU_MHPMCOUNTER7	6
-#define RISCV_PMU_MHPMCOUNTER8	7
-
-#define RISCV_OP_UNSUPP		(-EOPNOTSUPP)
-
-struct cpu_hw_events {
-	/* # currently enabled events*/
-	int			n_events;
-	/* currently enabled events */
-	struct perf_event	*events[RISCV_MAX_COUNTERS];
-	/* vendor-defined PMU data */
-	void			*platform;
-};
-
-struct riscv_pmu {
-	struct pmu	*pmu;
-
-	/* generic hw/cache events table */
-	const int	*hw_events;
-	const int	(*cache_events)[PERF_COUNT_HW_CACHE_MAX]
-				       [PERF_COUNT_HW_CACHE_OP_MAX]
-				       [PERF_COUNT_HW_CACHE_RESULT_MAX];
-	/* method used to map hw/cache events */
-	int		(*map_hw_event)(u64 config);
-	int		(*map_cache_event)(u64 config);
-
-	/* max generic hw events in map */
-	int		max_events;
-	/* number total counters, 2(base) + x(general) */
-	int		num_counters;
-	/* the width of the counter */
-	int		counter_width;
-
-	/* vendor-defined PMU features */
-	void		*platform;
-
-	irqreturn_t	(*handle_irq)(int irq_num, void *dev);
-	int		irq;
-};
-
-#endif
-#ifdef CONFIG_PERF_EVENTS
 #define perf_arch_bpf_user_pt_regs(regs) (struct user_regs_struct *)regs
-#endif
-
 #endif /* _ASM_RISCV_PERF_EVENT_H */
diff --git a/arch/riscv/include/asm/sbi.h b/arch/riscv/include/asm/sbi.h
index d1c37479d828..4a430ae60eaa 100644
--- a/arch/riscv/include/asm/sbi.h
+++ b/arch/riscv/include/asm/sbi.h
@@ -29,6 +29,7 @@ enum sbi_ext_id {
 	SBI_EXT_RFENCE = 0x52464E43,
 	SBI_EXT_HSM = 0x48534D,
 	SBI_EXT_SRST = 0x53525354,
+	SBI_EXT_PMU = 0x504D55,
 
 	/* Experimentals extensions must lie within this range */
 	SBI_EXT_EXPERIMENTAL_START = 0x08000000,
@@ -95,6 +96,98 @@ enum sbi_srst_reset_reason {
 	SBI_SRST_RESET_REASON_SYS_FAILURE,
 };
 
+enum sbi_ext_pmu_fid {
+	SBI_EXT_PMU_NUM_COUNTERS = 0,
+	SBI_EXT_PMU_COUNTER_GET_INFO,
+	SBI_EXT_PMU_COUNTER_CFG_MATCH,
+	SBI_EXT_PMU_COUNTER_START,
+	SBI_EXT_PMU_COUNTER_STOP,
+	SBI_EXT_PMU_COUNTER_FW_READ,
+};
+
+#define RISCV_PMU_RAW_EVENT_MASK GENMASK_ULL(55, 0)
+#define RISCV_PMU_RAW_EVENT_IDX 0x20000
+
+/** General pmu event codes specified in SBI PMU extension */
+enum sbi_pmu_hw_generic_events_t {
+	SBI_PMU_HW_NO_EVENT			= 0,
+	SBI_PMU_HW_CPU_CYCLES			= 1,
+	SBI_PMU_HW_INSTRUCTIONS			= 2,
+	SBI_PMU_HW_CACHE_REFERENCES		= 3,
+	SBI_PMU_HW_CACHE_MISSES			= 4,
+	SBI_PMU_HW_BRANCH_INSTRUCTIONS		= 5,
+	SBI_PMU_HW_BRANCH_MISSES		= 6,
+	SBI_PMU_HW_BUS_CYCLES			= 7,
+	SBI_PMU_HW_STALLED_CYCLES_FRONTEND	= 8,
+	SBI_PMU_HW_STALLED_CYCLES_BACKEND	= 9,
+	SBI_PMU_HW_REF_CPU_CYCLES		= 10,
+
+	SBI_PMU_HW_GENERAL_MAX,
+};
+
+/**
+ * Special "firmware" events provided by the firmware, even if the hardware
+ * does not support performance events. These events are encoded as a raw
+ * event type in Linux kernel perf framework.
+ */
+enum sbi_pmu_fw_generic_events_t {
+	SBI_PMU_FW_MISALIGNED_LOAD	= 0,
+	SBI_PMU_FW_MISALIGNED_STORE	= 1,
+	SBI_PMU_FW_ACCESS_LOAD		= 2,
+	SBI_PMU_FW_ACCESS_STORE		= 3,
+	SBI_PMU_FW_ILLEGAL_INSN		= 4,
+	SBI_PMU_FW_SET_TIMER		= 5,
+	SBI_PMU_FW_IPI_SENT		= 6,
+	SBI_PMU_FW_IPI_RECVD		= 7,
+	SBI_PMU_FW_FENCE_I_SENT		= 8,
+	SBI_PMU_FW_FENCE_I_RECVD	= 9,
+	SBI_PMU_FW_SFENCE_VMA_SENT	= 10,
+	SBI_PMU_FW_SFENCE_VMA_RCVD	= 11,
+	SBI_PMU_FW_SFENCE_VMA_ASID_SENT	= 12,
+	SBI_PMU_FW_SFENCE_VMA_ASID_RCVD	= 13,
+
+	SBI_PMU_FW_HFENCE_GVMA_SENT	= 14,
+	SBI_PMU_FW_HFENCE_GVMA_RCVD	= 15,
+	SBI_PMU_FW_HFENCE_GVMA_VMID_SENT = 16,
+	SBI_PMU_FW_HFENCE_GVMA_VMID_RCVD = 17,
+
+	SBI_PMU_FW_HFENCE_VVMA_SENT	= 18,
+	SBI_PMU_FW_HFENCE_VVMA_RCVD	= 19,
+	SBI_PMU_FW_HFENCE_VVMA_ASID_SENT = 20,
+	SBI_PMU_FW_HFENCE_VVMA_ASID_RCVD = 21,
+	SBI_PMU_FW_MAX,
+};
+
+/* SBI PMU event types */
+enum sbi_pmu_event_type {
+	SBI_PMU_EVENT_TYPE_HW = 0x0,
+	SBI_PMU_EVENT_TYPE_CACHE = 0x1,
+	SBI_PMU_EVENT_TYPE_RAW = 0x2,
+	SBI_PMU_EVENT_TYPE_FW = 0xf,
+};
+
+/* SBI PMU event types */
+enum sbi_pmu_ctr_type {
+	SBI_PMU_CTR_TYPE_HW = 0x0,
+	SBI_PMU_CTR_TYPE_FW,
+};
+
+/* Flags defined for config matching function */
+#define SBI_PMU_CFG_FLAG_SKIP_MATCH	(1 << 0)
+#define SBI_PMU_CFG_FLAG_CLEAR_VALUE	(1 << 1)
+#define SBI_PMU_CFG_FLAG_AUTO_START	(1 << 2)
+#define SBI_PMU_CFG_FLAG_SET_VUINH	(1 << 3)
+#define SBI_PMU_CFG_FLAG_SET_VSNH	(1 << 4)
+#define SBI_PMU_CFG_FLAG_SET_UINH	(1 << 5)
+#define SBI_PMU_CFG_FLAG_SET_SINH	(1 << 6)
+#define SBI_PMU_CFG_FLAG_SET_MINH	(1 << 7)
+
+/* Flags defined for counter start function */
+#define SBI_PMU_START_FLAG_SET_INIT_VALUE (1 << 0)
+
+/* Flags defined for counter stop function */
+#define SBI_PMU_STOP_FLAG_RESET (1 << 0)
+
 #define SBI_SPEC_VERSION_DEFAULT	0x1
 #define SBI_SPEC_VERSION_MAJOR_SHIFT	24
 #define SBI_SPEC_VERSION_MAJOR_MASK	0x7f
@@ -108,6 +201,8 @@ enum sbi_srst_reset_reason {
 #define SBI_ERR_DENIED		-4
 #define SBI_ERR_INVALID_ADDRESS	-5
 #define SBI_ERR_ALREADY_AVAILABLE -6
+#define SBI_ERR_ALREADY_STARTED -7
+#define SBI_ERR_ALREADY_STOPPED -8
 
 extern unsigned long sbi_spec_version;
 struct sbiret {
diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile
index 612556faa527..fb63b462ff85 100644
--- a/arch/riscv/kernel/Makefile
+++ b/arch/riscv/kernel/Makefile
@@ -51,7 +51,6 @@ obj-$(CONFIG_MODULE_SECTIONS)	+= module-sections.o
 obj-$(CONFIG_FUNCTION_TRACER)	+= mcount.o ftrace.o
 obj-$(CONFIG_DYNAMIC_FTRACE)	+= mcount-dyn.o
 
-obj-$(CONFIG_RISCV_BASE_PMU)	+= perf_event.o
 obj-$(CONFIG_PERF_EVENTS)	+= perf_callchain.o
 obj-$(CONFIG_HAVE_PERF_REGS)	+= perf_regs.o
 obj-$(CONFIG_RISCV_SBI)		+= sbi.o
diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c
index ecc2a09a66a9..d2a936195295 100644
--- a/arch/riscv/kernel/cpu.c
+++ b/arch/riscv/kernel/cpu.c
@@ -87,6 +87,7 @@ int riscv_of_parent_hartid(struct device_node *node)
  *    extensions by an underscore.
  */
 static struct riscv_isa_ext_data isa_ext_arr[] = {
+	__RISCV_ISA_EXT_DATA(sscofpmf, RISCV_ISA_EXT_SSCOFPMF),
 	__RISCV_ISA_EXT_DATA("", RISCV_ISA_EXT_MAX),
 };
 
diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
index a43c08af5f4b..1b2d42d7f589 100644
--- a/arch/riscv/kernel/cpufeature.c
+++ b/arch/riscv/kernel/cpufeature.c
@@ -190,6 +190,8 @@ void __init riscv_fill_hwcap(void)
 			if (!ext_long) {
 				this_hwcap |= isa2hwcap[(unsigned char)(*ext)];
 				set_bit(*ext - 'a', this_isa);
+			} else {
+				SET_ISA_EXT_MAP("sscofpmf", RISCV_ISA_EXT_SSCOFPMF);
 			}
 #undef SET_ISA_EXT_MAP
 		}
diff --git a/arch/riscv/kernel/perf_event.c b/arch/riscv/kernel/perf_event.c
deleted file mode 100644
index c835f0362d94..000000000000
--- a/arch/riscv/kernel/perf_event.c
+++ /dev/null
@@ -1,485 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-/*
- * Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de>
- * Copyright (C) 2008-2009 Red Hat, Inc., Ingo Molnar
- * Copyright (C) 2009 Jaswinder Singh Rajput
- * Copyright (C) 2009 Advanced Micro Devices, Inc., Robert Richter
- * Copyright (C) 2008-2009 Red Hat, Inc., Peter Zijlstra
- * Copyright (C) 2009 Intel Corporation, <markus.t.metzger@intel.com>
- * Copyright (C) 2009 Google, Inc., Stephane Eranian
- * Copyright 2014 Tilera Corporation. All Rights Reserved.
- * Copyright (C) 2018 Andes Technology Corporation
- *
- * Perf_events support for RISC-V platforms.
- *
- * Since the spec. (as of now, Priv-Spec 1.10) does not provide enough
- * functionality for perf event to fully work, this file provides
- * the very basic framework only.
- *
- * For platform portings, please check Documentations/riscv/pmu.txt.
- *
- * The Copyright line includes x86 and tile ones.
- */
-
-#include <linux/kprobes.h>
-#include <linux/kernel.h>
-#include <linux/kdebug.h>
-#include <linux/mutex.h>
-#include <linux/bitmap.h>
-#include <linux/irq.h>
-#include <linux/perf_event.h>
-#include <linux/atomic.h>
-#include <linux/of.h>
-#include <asm/perf_event.h>
-
-static const struct riscv_pmu *riscv_pmu __read_mostly;
-static DEFINE_PER_CPU(struct cpu_hw_events, cpu_hw_events);
-
-/*
- * Hardware & cache maps and their methods
- */
-
-static const int riscv_hw_event_map[] = {
-	[PERF_COUNT_HW_CPU_CYCLES]		= RISCV_PMU_CYCLE,
-	[PERF_COUNT_HW_INSTRUCTIONS]		= RISCV_PMU_INSTRET,
-	[PERF_COUNT_HW_CACHE_REFERENCES]	= RISCV_OP_UNSUPP,
-	[PERF_COUNT_HW_CACHE_MISSES]		= RISCV_OP_UNSUPP,
-	[PERF_COUNT_HW_BRANCH_INSTRUCTIONS]	= RISCV_OP_UNSUPP,
-	[PERF_COUNT_HW_BRANCH_MISSES]		= RISCV_OP_UNSUPP,
-	[PERF_COUNT_HW_BUS_CYCLES]		= RISCV_OP_UNSUPP,
-};
-
-#define C(x) PERF_COUNT_HW_CACHE_##x
-static const int riscv_cache_event_map[PERF_COUNT_HW_CACHE_MAX]
-[PERF_COUNT_HW_CACHE_OP_MAX]
-[PERF_COUNT_HW_CACHE_RESULT_MAX] = {
-	[C(L1D)] = {
-		[C(OP_READ)] = {
-			[C(RESULT_ACCESS)] = RISCV_OP_UNSUPP,
-			[C(RESULT_MISS)] = RISCV_OP_UNSUPP,
-		},
-		[C(OP_WRITE)] = {
-			[C(RESULT_ACCESS)] = RISCV_OP_UNSUPP,
-			[C(RESULT_MISS)] = RISCV_OP_UNSUPP,
-		},
-		[C(OP_PREFETCH)] = {
-			[C(RESULT_ACCESS)] = RISCV_OP_UNSUPP,
-			[C(RESULT_MISS)] = RISCV_OP_UNSUPP,
-		},
-	},
-	[C(L1I)] = {
-		[C(OP_READ)] = {
-			[C(RESULT_ACCESS)] = RISCV_OP_UNSUPP,
-			[C(RESULT_MISS)] = RISCV_OP_UNSUPP,
-		},
-		[C(OP_WRITE)] = {
-			[C(RESULT_ACCESS)] = RISCV_OP_UNSUPP,
-			[C(RESULT_MISS)] = RISCV_OP_UNSUPP,
-		},
-		[C(OP_PREFETCH)] = {
-			[C(RESULT_ACCESS)] = RISCV_OP_UNSUPP,
-			[C(RESULT_MISS)] = RISCV_OP_UNSUPP,
-		},
-	},
-	[C(LL)] = {
-		[C(OP_READ)] = {
-			[C(RESULT_ACCESS)] = RISCV_OP_UNSUPP,
-			[C(RESULT_MISS)] = RISCV_OP_UNSUPP,
-		},
-		[C(OP_WRITE)] = {
-			[C(RESULT_ACCESS)] = RISCV_OP_UNSUPP,
-			[C(RESULT_MISS)] = RISCV_OP_UNSUPP,
-		},
-		[C(OP_PREFETCH)] = {
-			[C(RESULT_ACCESS)] = RISCV_OP_UNSUPP,
-			[C(RESULT_MISS)] = RISCV_OP_UNSUPP,
-		},
-	},
-	[C(DTLB)] = {
-		[C(OP_READ)] = {
-			[C(RESULT_ACCESS)] =  RISCV_OP_UNSUPP,
-			[C(RESULT_MISS)] =  RISCV_OP_UNSUPP,
-		},
-		[C(OP_WRITE)] = {
-			[C(RESULT_ACCESS)] = RISCV_OP_UNSUPP,
-			[C(RESULT_MISS)] = RISCV_OP_UNSUPP,
-		},
-		[C(OP_PREFETCH)] = {
-			[C(RESULT_ACCESS)] = RISCV_OP_UNSUPP,
-			[C(RESULT_MISS)] = RISCV_OP_UNSUPP,
-		},
-	},
-	[C(ITLB)] = {
-		[C(OP_READ)] = {
-			[C(RESULT_ACCESS)] = RISCV_OP_UNSUPP,
-			[C(RESULT_MISS)] = RISCV_OP_UNSUPP,
-		},
-		[C(OP_WRITE)] = {
-			[C(RESULT_ACCESS)] = RISCV_OP_UNSUPP,
-			[C(RESULT_MISS)] = RISCV_OP_UNSUPP,
-		},
-		[C(OP_PREFETCH)] = {
-			[C(RESULT_ACCESS)] = RISCV_OP_UNSUPP,
-			[C(RESULT_MISS)] = RISCV_OP_UNSUPP,
-		},
-	},
-	[C(BPU)] = {
-		[C(OP_READ)] = {
-			[C(RESULT_ACCESS)] = RISCV_OP_UNSUPP,
-			[C(RESULT_MISS)] = RISCV_OP_UNSUPP,
-		},
-		[C(OP_WRITE)] = {
-			[C(RESULT_ACCESS)] = RISCV_OP_UNSUPP,
-			[C(RESULT_MISS)] = RISCV_OP_UNSUPP,
-		},
-		[C(OP_PREFETCH)] = {
-			[C(RESULT_ACCESS)] = RISCV_OP_UNSUPP,
-			[C(RESULT_MISS)] = RISCV_OP_UNSUPP,
-		},
-	},
-};
-
-static int riscv_map_hw_event(u64 config)
-{
-	if (config >= riscv_pmu->max_events)
-		return -EINVAL;
-
-	return riscv_pmu->hw_events[config];
-}
-
-static int riscv_map_cache_decode(u64 config, unsigned int *type,
-			   unsigned int *op, unsigned int *result)
-{
-	return -ENOENT;
-}
-
-static int riscv_map_cache_event(u64 config)
-{
-	unsigned int type, op, result;
-	int err = -ENOENT;
-		int code;
-
-	err = riscv_map_cache_decode(config, &type, &op, &result);
-	if (!riscv_pmu->cache_events || err)
-		return err;
-
-	if (type >= PERF_COUNT_HW_CACHE_MAX ||
-	    op >= PERF_COUNT_HW_CACHE_OP_MAX ||
-	    result >= PERF_COUNT_HW_CACHE_RESULT_MAX)
-		return -EINVAL;
-
-	code = (*riscv_pmu->cache_events)[type][op][result];
-	if (code == RISCV_OP_UNSUPP)
-		return -EINVAL;
-
-	return code;
-}
-
-/*
- * Low-level functions: reading/writing counters
- */
-
-static inline u64 read_counter(int idx)
-{
-	u64 val = 0;
-
-	switch (idx) {
-	case RISCV_PMU_CYCLE:
-		val = csr_read(CSR_CYCLE);
-		break;
-	case RISCV_PMU_INSTRET:
-		val = csr_read(CSR_INSTRET);
-		break;
-	default:
-		WARN_ON_ONCE(idx < 0 ||	idx > RISCV_MAX_COUNTERS);
-		return -EINVAL;
-	}
-
-	return val;
-}
-
-static inline void write_counter(int idx, u64 value)
-{
-	/* currently not supported */
-	WARN_ON_ONCE(1);
-}
-
-/*
- * pmu->read: read and update the counter
- *
- * Other architectures' implementation often have a xxx_perf_event_update
- * routine, which can return counter values when called in the IRQ, but
- * return void when being called by the pmu->read method.
- */
-static void riscv_pmu_read(struct perf_event *event)
-{
-	struct hw_perf_event *hwc = &event->hw;
-	u64 prev_raw_count, new_raw_count;
-	u64 oldval;
-	int idx = hwc->idx;
-	u64 delta;
-
-	do {
-		prev_raw_count = local64_read(&hwc->prev_count);
-		new_raw_count = read_counter(idx);
-
-		oldval = local64_cmpxchg(&hwc->prev_count, prev_raw_count,
-					 new_raw_count);
-	} while (oldval != prev_raw_count);
-
-	/*
-	 * delta is the value to update the counter we maintain in the kernel.
-	 */
-	delta = (new_raw_count - prev_raw_count) &
-		((1ULL << riscv_pmu->counter_width) - 1);
-	local64_add(delta, &event->count);
-	/*
-	 * Something like local64_sub(delta, &hwc->period_left) here is
-	 * needed if there is an interrupt for perf.
-	 */
-}
-
-/*
- * State transition functions:
- *
- * stop()/start() & add()/del()
- */
-
-/*
- * pmu->stop: stop the counter
- */
-static void riscv_pmu_stop(struct perf_event *event, int flags)
-{
-	struct hw_perf_event *hwc = &event->hw;
-
-	WARN_ON_ONCE(hwc->state & PERF_HES_STOPPED);
-	hwc->state |= PERF_HES_STOPPED;
-
-	if ((flags & PERF_EF_UPDATE) && !(hwc->state & PERF_HES_UPTODATE)) {
-		riscv_pmu->pmu->read(event);
-		hwc->state |= PERF_HES_UPTODATE;
-	}
-}
-
-/*
- * pmu->start: start the event.
- */
-static void riscv_pmu_start(struct perf_event *event, int flags)
-{
-	struct hw_perf_event *hwc = &event->hw;
-
-	if (WARN_ON_ONCE(!(event->hw.state & PERF_HES_STOPPED)))
-		return;
-
-	if (flags & PERF_EF_RELOAD) {
-		WARN_ON_ONCE(!(event->hw.state & PERF_HES_UPTODATE));
-
-		/*
-		 * Set the counter to the period to the next interrupt here,
-		 * if you have any.
-		 */
-	}
-
-	hwc->state = 0;
-	perf_event_update_userpage(event);
-
-	/*
-	 * Since we cannot write to counters, this serves as an initialization
-	 * to the delta-mechanism in pmu->read(); otherwise, the delta would be
-	 * wrong when pmu->read is called for the first time.
-	 */
-	local64_set(&hwc->prev_count, read_counter(hwc->idx));
-}
-
-/*
- * pmu->add: add the event to PMU.
- */
-static int riscv_pmu_add(struct perf_event *event, int flags)
-{
-	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
-	struct hw_perf_event *hwc = &event->hw;
-
-	if (cpuc->n_events == riscv_pmu->num_counters)
-		return -ENOSPC;
-
-	/*
-	 * We don't have general conunters, so no binding-event-to-counter
-	 * process here.
-	 *
-	 * Indexing using hwc->config generally not works, since config may
-	 * contain extra information, but here the only info we have in
-	 * hwc->config is the event index.
-	 */
-	hwc->idx = hwc->config;
-	cpuc->events[hwc->idx] = event;
-	cpuc->n_events++;
-
-	hwc->state = PERF_HES_UPTODATE | PERF_HES_STOPPED;
-
-	if (flags & PERF_EF_START)
-		riscv_pmu->pmu->start(event, PERF_EF_RELOAD);
-
-	return 0;
-}
-
-/*
- * pmu->del: delete the event from PMU.
- */
-static void riscv_pmu_del(struct perf_event *event, int flags)
-{
-	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
-	struct hw_perf_event *hwc = &event->hw;
-
-	cpuc->events[hwc->idx] = NULL;
-	cpuc->n_events--;
-	riscv_pmu->pmu->stop(event, PERF_EF_UPDATE);
-	perf_event_update_userpage(event);
-}
-
-/*
- * Interrupt: a skeletion for reference.
- */
-
-static DEFINE_MUTEX(pmc_reserve_mutex);
-
-static irqreturn_t riscv_base_pmu_handle_irq(int irq_num, void *dev)
-{
-	return IRQ_NONE;
-}
-
-static int reserve_pmc_hardware(void)
-{
-	int err = 0;
-
-	mutex_lock(&pmc_reserve_mutex);
-	if (riscv_pmu->irq >= 0 && riscv_pmu->handle_irq) {
-		err = request_irq(riscv_pmu->irq, riscv_pmu->handle_irq,
-				  IRQF_PERCPU, "riscv-base-perf", NULL);
-	}
-	mutex_unlock(&pmc_reserve_mutex);
-
-	return err;
-}
-
-static void release_pmc_hardware(void)
-{
-	mutex_lock(&pmc_reserve_mutex);
-	if (riscv_pmu->irq >= 0)
-		free_irq(riscv_pmu->irq, NULL);
-	mutex_unlock(&pmc_reserve_mutex);
-}
-
-/*
- * Event Initialization/Finalization
- */
-
-static atomic_t riscv_active_events = ATOMIC_INIT(0);
-
-static void riscv_event_destroy(struct perf_event *event)
-{
-	if (atomic_dec_return(&riscv_active_events) == 0)
-		release_pmc_hardware();
-}
-
-static int riscv_event_init(struct perf_event *event)
-{
-	struct perf_event_attr *attr = &event->attr;
-	struct hw_perf_event *hwc = &event->hw;
-	int err;
-	int code;
-
-	if (atomic_inc_return(&riscv_active_events) == 1) {
-		err = reserve_pmc_hardware();
-
-		if (err) {
-			pr_warn("PMC hardware not available\n");
-			atomic_dec(&riscv_active_events);
-			return -EBUSY;
-		}
-	}
-
-	switch (event->attr.type) {
-	case PERF_TYPE_HARDWARE:
-		code = riscv_pmu->map_hw_event(attr->config);
-		break;
-	case PERF_TYPE_HW_CACHE:
-		code = riscv_pmu->map_cache_event(attr->config);
-		break;
-	case PERF_TYPE_RAW:
-		return -EOPNOTSUPP;
-	default:
-		return -ENOENT;
-	}
-
-	event->destroy = riscv_event_destroy;
-	if (code < 0) {
-		event->destroy(event);
-		return code;
-	}
-
-	/*
-	 * idx is set to -1 because the index of a general event should not be
-	 * decided until binding to some counter in pmu->add().
-	 *
-	 * But since we don't have such support, later in pmu->add(), we just
-	 * use hwc->config as the index instead.
-	 */
-	hwc->config = code;
-	hwc->idx = -1;
-
-	return 0;
-}
-
-/*
- * Initialization
- */
-
-static struct pmu min_pmu = {
-	.name		= "riscv-base",
-	.event_init	= riscv_event_init,
-	.add		= riscv_pmu_add,
-	.del		= riscv_pmu_del,
-	.start		= riscv_pmu_start,
-	.stop		= riscv_pmu_stop,
-	.read		= riscv_pmu_read,
-};
-
-static const struct riscv_pmu riscv_base_pmu = {
-	.pmu = &min_pmu,
-	.max_events = ARRAY_SIZE(riscv_hw_event_map),
-	.map_hw_event = riscv_map_hw_event,
-	.hw_events = riscv_hw_event_map,
-	.map_cache_event = riscv_map_cache_event,
-	.cache_events = &riscv_cache_event_map,
-	.counter_width = 63,
-	.num_counters = RISCV_BASE_COUNTERS + 0,
-	.handle_irq = &riscv_base_pmu_handle_irq,
-
-	/* This means this PMU has no IRQ. */
-	.irq = -1,
-};
-
-static const struct of_device_id riscv_pmu_of_ids[] = {
-	{.compatible = "riscv,base-pmu",	.data = &riscv_base_pmu},
-	{ /* sentinel value */ }
-};
-
-static int __init init_hw_perf_events(void)
-{
-	struct device_node *node = of_find_node_by_type(NULL, "pmu");
-	const struct of_device_id *of_id;
-
-	riscv_pmu = &riscv_base_pmu;
-
-	if (node) {
-		of_id = of_match_node(riscv_pmu_of_ids, node);
-
-		if (of_id)
-			riscv_pmu = of_id->data;
-		of_node_put(node);
-	}
-
-	perf_pmu_register(riscv_pmu->pmu, "cpu", PERF_TYPE_RAW);
-	return 0;
-}
-arch_initcall(init_hw_perf_events);
diff --git a/drivers/perf/Kconfig b/drivers/perf/Kconfig
index e1a0c44bc686..5645b5615c14 100644
--- a/drivers/perf/Kconfig
+++ b/drivers/perf/Kconfig
@@ -56,6 +56,36 @@ config ARM_PMU
 	  Say y if you want to use CPU performance monitors on ARM-based
 	  systems.
 
+config RISCV_PMU
+	depends on RISCV
+	bool "RISC-V PMU framework"
+	default y
+	help
+	  Say y if you want to use CPU performance monitors on RISCV-based
+	  systems. This provides the core PMU framework that abstracts common
+	  PMU functionalities in a core library so that different PMU drivers
+	  can reuse it.
+
+config RISCV_PMU_LEGACY
+	depends on RISCV_PMU
+	bool "RISC-V legacy PMU implementation"
+	default y
+	help
+	  Say y if you want to use the legacy CPU performance monitor
+	  implementation on RISC-V based systems. This only allows counting
+	  of cycle/instruction counter and doesn't support counter overflow,
+	  or programmable counters. It will be removed in future.
+
+config RISCV_PMU_SBI
+	depends on RISCV_PMU && RISCV_SBI
+	bool "RISC-V PMU based on SBI PMU extension"
+	default y
+	help
+	  Say y if you want to use the CPU performance monitor
+	  using SBI PMU extension on RISC-V based systems. This option provides
+	  full perf feature support i.e. counter overflow, privilege mode
+	  filtering, counter configuration.
+
 config ARM_PMU_ACPI
 	depends on ARM_PMU && ACPI
 	def_bool y
diff --git a/drivers/perf/Makefile b/drivers/perf/Makefile
index 2db5418d5b0a..f149735166e1 100644
--- a/drivers/perf/Makefile
+++ b/drivers/perf/Makefile
@@ -10,6 +10,9 @@ obj-$(CONFIG_FSL_IMX8_DDR_PMU) += fsl_imx8_ddr_perf.o
 obj-$(CONFIG_HISI_PMU) += hisilicon/
 obj-$(CONFIG_QCOM_L2_PMU)	+= qcom_l2_pmu.o
 obj-$(CONFIG_QCOM_L3_PMU) += qcom_l3_pmu.o
+obj-$(CONFIG_RISCV_PMU) += riscv_pmu.o
+obj-$(CONFIG_RISCV_PMU_LEGACY) += riscv_pmu_legacy.o
+obj-$(CONFIG_RISCV_PMU_SBI) += riscv_pmu_sbi.o
 obj-$(CONFIG_THUNDERX2_PMU) += thunderx2_pmu.o
 obj-$(CONFIG_XGENE_PMU) += xgene_pmu.o
 obj-$(CONFIG_ARM_SPE_PMU) += arm_spe_pmu.o
diff --git a/drivers/perf/riscv_pmu.c b/drivers/perf/riscv_pmu.c
new file mode 100644
index 000000000000..b2b8d2074ed0
--- /dev/null
+++ b/drivers/perf/riscv_pmu.c
@@ -0,0 +1,324 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * RISC-V performance counter support.
+ *
+ * Copyright (C) 2021 Western Digital Corporation or its affiliates.
+ *
+ * This implementation is based on old RISC-V perf and ARM perf event code
+ * which are in turn based on sparc64 and x86 code.
+ */
+
+#include <linux/cpumask.h>
+#include <linux/irq.h>
+#include <linux/irqdesc.h>
+#include <linux/perf/riscv_pmu.h>
+#include <linux/printk.h>
+#include <linux/smp.h>
+
+#include <asm/sbi.h>
+
+static unsigned long csr_read_num(int csr_num)
+{
+#define switchcase_csr_read(__csr_num, __val)		{\
+	case __csr_num:					\
+		__val = csr_read(__csr_num);		\
+		break; }
+#define switchcase_csr_read_2(__csr_num, __val)		{\
+	switchcase_csr_read(__csr_num + 0, __val)	 \
+	switchcase_csr_read(__csr_num + 1, __val)}
+#define switchcase_csr_read_4(__csr_num, __val)		{\
+	switchcase_csr_read_2(__csr_num + 0, __val)	 \
+	switchcase_csr_read_2(__csr_num + 2, __val)}
+#define switchcase_csr_read_8(__csr_num, __val)		{\
+	switchcase_csr_read_4(__csr_num + 0, __val)	 \
+	switchcase_csr_read_4(__csr_num + 4, __val)}
+#define switchcase_csr_read_16(__csr_num, __val)	{\
+	switchcase_csr_read_8(__csr_num + 0, __val)	 \
+	switchcase_csr_read_8(__csr_num + 8, __val)}
+#define switchcase_csr_read_32(__csr_num, __val)	{\
+	switchcase_csr_read_16(__csr_num + 0, __val)	 \
+	switchcase_csr_read_16(__csr_num + 16, __val)}
+
+	unsigned long ret = 0;
+
+	switch (csr_num) {
+	switchcase_csr_read_32(CSR_CYCLE, ret)
+	switchcase_csr_read_32(CSR_CYCLEH, ret)
+	default :
+		break;
+	}
+
+	return ret;
+#undef switchcase_csr_read_32
+#undef switchcase_csr_read_16
+#undef switchcase_csr_read_8
+#undef switchcase_csr_read_4
+#undef switchcase_csr_read_2
+#undef switchcase_csr_read
+}
+
+/*
+ * Read the CSR of a corresponding counter.
+ */
+unsigned long riscv_pmu_ctr_read_csr(unsigned long csr)
+{
+	if (csr < CSR_CYCLE || csr > CSR_HPMCOUNTER31H ||
+	   (csr > CSR_HPMCOUNTER31 && csr < CSR_CYCLEH)) {
+		pr_err("Invalid performance counter csr %lx\n", csr);
+		return -EINVAL;
+	}
+
+	return csr_read_num(csr);
+}
+
+u64 riscv_pmu_ctr_get_width_mask(struct perf_event *event)
+{
+	int cwidth;
+	struct riscv_pmu *rvpmu = to_riscv_pmu(event->pmu);
+	struct hw_perf_event *hwc = &event->hw;
+
+	if (!rvpmu->ctr_get_width)
+	/**
+	 * If the pmu driver doesn't support counter width, set it to default
+	 * maximum allowed by the specification.
+	 */
+		cwidth = 63;
+	else {
+		if (hwc->idx == -1)
+			/* Handle init case where idx is not initialized yet */
+			cwidth = rvpmu->ctr_get_width(0);
+		else
+			cwidth = rvpmu->ctr_get_width(hwc->idx);
+	}
+
+	return GENMASK_ULL(cwidth, 0);
+}
+
+u64 riscv_pmu_event_update(struct perf_event *event)
+{
+	struct riscv_pmu *rvpmu = to_riscv_pmu(event->pmu);
+	struct hw_perf_event *hwc = &event->hw;
+	u64 prev_raw_count, new_raw_count;
+	unsigned long cmask;
+	u64 oldval, delta;
+
+	if (!rvpmu->ctr_read)
+		return 0;
+
+	cmask = riscv_pmu_ctr_get_width_mask(event);
+
+	do {
+		prev_raw_count = local64_read(&hwc->prev_count);
+		new_raw_count = rvpmu->ctr_read(event);
+		oldval = local64_cmpxchg(&hwc->prev_count, prev_raw_count,
+					 new_raw_count);
+	} while (oldval != prev_raw_count);
+
+	delta = (new_raw_count - prev_raw_count) & cmask;
+	local64_add(delta, &event->count);
+	local64_sub(delta, &hwc->period_left);
+
+	return delta;
+}
+
+static void riscv_pmu_stop(struct perf_event *event, int flags)
+{
+	struct hw_perf_event *hwc = &event->hw;
+	struct riscv_pmu *rvpmu = to_riscv_pmu(event->pmu);
+
+	WARN_ON_ONCE(hwc->state & PERF_HES_STOPPED);
+
+	if (!(hwc->state & PERF_HES_STOPPED)) {
+		if (rvpmu->ctr_stop) {
+			rvpmu->ctr_stop(event, 0);
+			hwc->state |= PERF_HES_STOPPED;
+		}
+		riscv_pmu_event_update(event);
+		hwc->state |= PERF_HES_UPTODATE;
+	}
+}
+
+int riscv_pmu_event_set_period(struct perf_event *event)
+{
+	struct hw_perf_event *hwc = &event->hw;
+	s64 left = local64_read(&hwc->period_left);
+	s64 period = hwc->sample_period;
+	int overflow = 0;
+	uint64_t max_period = riscv_pmu_ctr_get_width_mask(event);
+
+	if (unlikely(left <= -period)) {
+		left = period;
+		local64_set(&hwc->period_left, left);
+		hwc->last_period = period;
+		overflow = 1;
+	}
+
+	if (unlikely(left <= 0)) {
+		left += period;
+		local64_set(&hwc->period_left, left);
+		hwc->last_period = period;
+		overflow = 1;
+	}
+
+	/*
+	 * Limit the maximum period to prevent the counter value
+	 * from overtaking the one we are about to program. In
+	 * effect we are reducing max_period to account for
+	 * interrupt latency (and we are being very conservative).
+	 */
+	if (left > (max_period >> 1))
+		left = (max_period >> 1);
+
+	local64_set(&hwc->prev_count, (u64)-left);
+	perf_event_update_userpage(event);
+
+	return overflow;
+}
+
+static void riscv_pmu_start(struct perf_event *event, int flags)
+{
+	struct hw_perf_event *hwc = &event->hw;
+	struct riscv_pmu *rvpmu = to_riscv_pmu(event->pmu);
+	uint64_t max_period = riscv_pmu_ctr_get_width_mask(event);
+	u64 init_val;
+
+	if (WARN_ON_ONCE(!(event->hw.state & PERF_HES_STOPPED)))
+		return;
+
+	if (flags & PERF_EF_RELOAD)
+		WARN_ON_ONCE(!(event->hw.state & PERF_HES_UPTODATE));
+
+	hwc->state = 0;
+	riscv_pmu_event_set_period(event);
+	init_val = local64_read(&hwc->prev_count) & max_period;
+	rvpmu->ctr_start(event, init_val);
+	perf_event_update_userpage(event);
+}
+
+static int riscv_pmu_add(struct perf_event *event, int flags)
+{
+	struct riscv_pmu *rvpmu = to_riscv_pmu(event->pmu);
+	struct cpu_hw_events *cpuc = this_cpu_ptr(rvpmu->hw_events);
+	struct hw_perf_event *hwc = &event->hw;
+	int idx;
+
+	idx = rvpmu->ctr_get_idx(event);
+	if (idx < 0)
+		return idx;
+
+	hwc->idx = idx;
+	cpuc->events[idx] = event;
+	cpuc->n_events++;
+	hwc->state = PERF_HES_UPTODATE | PERF_HES_STOPPED;
+	if (flags & PERF_EF_START)
+		riscv_pmu_start(event, PERF_EF_RELOAD);
+
+	/* Propagate our changes to the userspace mapping. */
+	perf_event_update_userpage(event);
+
+	return 0;
+}
+
+static void riscv_pmu_del(struct perf_event *event, int flags)
+{
+	struct riscv_pmu *rvpmu = to_riscv_pmu(event->pmu);
+	struct cpu_hw_events *cpuc = this_cpu_ptr(rvpmu->hw_events);
+	struct hw_perf_event *hwc = &event->hw;
+
+	riscv_pmu_stop(event, PERF_EF_UPDATE);
+	cpuc->events[hwc->idx] = NULL;
+	/* The firmware need to reset the counter mapping */
+	if (rvpmu->ctr_stop)
+		rvpmu->ctr_stop(event, RISCV_PMU_STOP_FLAG_RESET);
+	cpuc->n_events--;
+	if (rvpmu->ctr_clear_idx)
+		rvpmu->ctr_clear_idx(event);
+	perf_event_update_userpage(event);
+	hwc->idx = -1;
+}
+
+static void riscv_pmu_read(struct perf_event *event)
+{
+	riscv_pmu_event_update(event);
+}
+
+static int riscv_pmu_event_init(struct perf_event *event)
+{
+	struct hw_perf_event *hwc = &event->hw;
+	struct riscv_pmu *rvpmu = to_riscv_pmu(event->pmu);
+	int mapped_event;
+	u64 event_config = 0;
+	uint64_t cmask;
+
+	hwc->flags = 0;
+	mapped_event = rvpmu->event_map(event, &event_config);
+	if (mapped_event < 0) {
+		pr_debug("event %x:%llx not supported\n", event->attr.type,
+			 event->attr.config);
+		return mapped_event;
+	}
+
+	/*
+	 * idx is set to -1 because the index of a general event should not be
+	 * decided until binding to some counter in pmu->add().
+	 * config will contain the information about counter CSR
+	 * the idx will contain the counter index
+	 */
+	hwc->config = event_config;
+	hwc->idx = -1;
+	hwc->event_base = mapped_event;
+
+	if (!is_sampling_event(event)) {
+		/*
+		 * For non-sampling runs, limit the sample_period to half
+		 * of the counter width. That way, the new counter value
+		 * is far less likely to overtake the previous one unless
+		 * you have some serious IRQ latency issues.
+		 */
+		cmask = riscv_pmu_ctr_get_width_mask(event);
+		hwc->sample_period  =  cmask >> 1;
+		hwc->last_period    = hwc->sample_period;
+		local64_set(&hwc->period_left, hwc->sample_period);
+	}
+
+	return 0;
+}
+
+struct riscv_pmu *riscv_pmu_alloc(void)
+{
+	struct riscv_pmu *pmu;
+	int cpuid, i;
+	struct cpu_hw_events *cpuc;
+
+	pmu = kzalloc(sizeof(*pmu), GFP_KERNEL);
+	if (!pmu)
+		goto out;
+
+	pmu->hw_events = alloc_percpu_gfp(struct cpu_hw_events, GFP_KERNEL);
+	if (!pmu->hw_events) {
+		pr_info("failed to allocate per-cpu PMU data.\n");
+		goto out_free_pmu;
+	}
+
+	for_each_possible_cpu(cpuid) {
+		cpuc = per_cpu_ptr(pmu->hw_events, cpuid);
+		cpuc->n_events = 0;
+		for (i = 0; i < RISCV_MAX_COUNTERS; i++)
+			cpuc->events[i] = NULL;
+	}
+	pmu->pmu = (struct pmu) {
+		.event_init	= riscv_pmu_event_init,
+		.add		= riscv_pmu_add,
+		.del		= riscv_pmu_del,
+		.start		= riscv_pmu_start,
+		.stop		= riscv_pmu_stop,
+		.read		= riscv_pmu_read,
+	};
+
+	return pmu;
+
+out_free_pmu:
+	kfree(pmu);
+out:
+	return NULL;
+}
diff --git a/drivers/perf/riscv_pmu_legacy.c b/drivers/perf/riscv_pmu_legacy.c
new file mode 100644
index 000000000000..342778782359
--- /dev/null
+++ b/drivers/perf/riscv_pmu_legacy.c
@@ -0,0 +1,142 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * RISC-V performance counter support.
+ *
+ * Copyright (C) 2021 Western Digital Corporation or its affiliates.
+ *
+ * This implementation is based on old RISC-V perf and ARM perf event code
+ * which are in turn based on sparc64 and x86 code.
+ */
+
+#include <linux/mod_devicetable.h>
+#include <linux/perf/riscv_pmu.h>
+#include <linux/platform_device.h>
+
+#define RISCV_PMU_LEGACY_CYCLE		0
+#define RISCV_PMU_LEGACY_INSTRET	1
+#define RISCV_PMU_LEGACY_NUM_CTR	2
+
+static bool pmu_init_done;
+
+static int pmu_legacy_ctr_get_idx(struct perf_event *event)
+{
+	struct perf_event_attr *attr = &event->attr;
+
+	if (event->attr.type != PERF_TYPE_HARDWARE)
+		return -EOPNOTSUPP;
+	if (attr->config == PERF_COUNT_HW_CPU_CYCLES)
+		return RISCV_PMU_LEGACY_CYCLE;
+	else if (attr->config == PERF_COUNT_HW_INSTRUCTIONS)
+		return RISCV_PMU_LEGACY_INSTRET;
+	else
+		return -EOPNOTSUPP;
+}
+
+/* For legacy config & counter index are same */
+static int pmu_legacy_event_map(struct perf_event *event, u64 *config)
+{
+	return pmu_legacy_ctr_get_idx(event);
+}
+
+static u64 pmu_legacy_read_ctr(struct perf_event *event)
+{
+	struct hw_perf_event *hwc = &event->hw;
+	int idx = hwc->idx;
+	u64 val;
+
+	if (idx == RISCV_PMU_LEGACY_CYCLE) {
+		val = riscv_pmu_ctr_read_csr(CSR_CYCLE);
+		if (IS_ENABLED(CONFIG_32BIT))
+			val = (u64)riscv_pmu_ctr_read_csr(CSR_CYCLEH) << 32 | val;
+	} else if (idx == RISCV_PMU_LEGACY_INSTRET) {
+		val = riscv_pmu_ctr_read_csr(CSR_INSTRET);
+		if (IS_ENABLED(CONFIG_32BIT))
+			val = ((u64)riscv_pmu_ctr_read_csr(CSR_INSTRETH)) << 32 | val;
+	} else
+		return 0;
+
+	return val;
+}
+
+static void pmu_legacy_ctr_start(struct perf_event *event, u64 ival)
+{
+	struct hw_perf_event *hwc = &event->hw;
+	u64 initial_val = pmu_legacy_read_ctr(event);
+
+	/**
+	 * The legacy method doesn't really have a start/stop method.
+	 * It also can not update the counter with a initial value.
+	 * But we still need to set the prev_count so that read() can compute
+	 * the delta. Just use the current counter value to set the prev_count.
+	 */
+	local64_set(&hwc->prev_count, initial_val);
+}
+
+/**
+ * This is just a simple implementation to allow legacy implementations
+ * compatible with new RISC-V PMU driver framework.
+ * This driver only allows reading two counters i.e CYCLE & INSTRET.
+ * However, it can not start or stop the counter. Thus, it is not very useful
+ * will be removed in future.
+ */
+static void pmu_legacy_init(struct riscv_pmu *pmu)
+{
+	pr_info("Legacy PMU implementation is available\n");
+
+	pmu->num_counters = RISCV_PMU_LEGACY_NUM_CTR;
+	pmu->ctr_start = pmu_legacy_ctr_start;
+	pmu->ctr_stop = NULL;
+	pmu->event_map = pmu_legacy_event_map;
+	pmu->ctr_get_idx = pmu_legacy_ctr_get_idx;
+	pmu->ctr_get_width = NULL;
+	pmu->ctr_clear_idx = NULL;
+	pmu->ctr_read = pmu_legacy_read_ctr;
+
+	perf_pmu_register(&pmu->pmu, "cpu", PERF_TYPE_RAW);
+}
+
+static int pmu_legacy_device_probe(struct platform_device *pdev)
+{
+	struct riscv_pmu *pmu = NULL;
+
+	pmu = riscv_pmu_alloc();
+	if (!pmu)
+		return -ENOMEM;
+	pmu_legacy_init(pmu);
+
+	return 0;
+}
+
+static struct platform_driver pmu_legacy_driver = {
+	.probe		= pmu_legacy_device_probe,
+	.driver		= {
+		.name	= RISCV_PMU_LEGACY_PDEV_NAME,
+	},
+};
+
+static int __init riscv_pmu_legacy_devinit(void)
+{
+	int ret;
+	struct platform_device *pdev;
+
+	if (likely(pmu_init_done))
+		return 0;
+
+	ret = platform_driver_register(&pmu_legacy_driver);
+	if (ret)
+		return ret;
+
+	pdev = platform_device_register_simple(RISCV_PMU_LEGACY_PDEV_NAME, -1, NULL, 0);
+	if (IS_ERR(pdev)) {
+		platform_driver_unregister(&pmu_legacy_driver);
+		return PTR_ERR(pdev);
+	}
+
+	return ret;
+}
+late_initcall(riscv_pmu_legacy_devinit);
+
+void riscv_pmu_legacy_skip_init(void)
+{
+	pmu_init_done = true;
+}
diff --git a/drivers/perf/riscv_pmu_sbi.c b/drivers/perf/riscv_pmu_sbi.c
new file mode 100644
index 000000000000..a1317a483512
--- /dev/null
+++ b/drivers/perf/riscv_pmu_sbi.c
@@ -0,0 +1,790 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * RISC-V performance counter support.
+ *
+ * Copyright (C) 2021 Western Digital Corporation or its affiliates.
+ *
+ * This code is based on ARM perf event code which is in turn based on
+ * sparc64 and x86 code.
+ */
+
+#define pr_fmt(fmt) "riscv-pmu-sbi: " fmt
+
+#include <linux/mod_devicetable.h>
+#include <linux/perf/riscv_pmu.h>
+#include <linux/platform_device.h>
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/of_irq.h>
+#include <linux/of.h>
+
+#include <asm/sbi.h>
+#include <asm/hwcap.h>
+
+union sbi_pmu_ctr_info {
+	unsigned long value;
+	struct {
+		unsigned long csr:12;
+		unsigned long width:6;
+#if __riscv_xlen == 32
+		unsigned long reserved:13;
+#else
+		unsigned long reserved:45;
+#endif
+		unsigned long type:1;
+	};
+};
+
+/**
+ * RISC-V doesn't have hetergenous harts yet. This need to be part of
+ * per_cpu in case of harts with different pmu counters
+ */
+static union sbi_pmu_ctr_info *pmu_ctr_list;
+static unsigned int riscv_pmu_irq;
+
+struct sbi_pmu_event_data {
+	union {
+		union {
+			struct hw_gen_event {
+				uint32_t event_code:16;
+				uint32_t event_type:4;
+				uint32_t reserved:12;
+			} hw_gen_event;
+			struct hw_cache_event {
+				uint32_t result_id:1;
+				uint32_t op_id:2;
+				uint32_t cache_id:13;
+				uint32_t event_type:4;
+				uint32_t reserved:12;
+			} hw_cache_event;
+		};
+		uint32_t event_idx;
+	};
+};
+
+static const struct sbi_pmu_event_data pmu_hw_event_map[] = {
+	[PERF_COUNT_HW_CPU_CYCLES]		= {.hw_gen_event = {
+							SBI_PMU_HW_CPU_CYCLES,
+							SBI_PMU_EVENT_TYPE_HW, 0}},
+	[PERF_COUNT_HW_INSTRUCTIONS]		= {.hw_gen_event = {
+							SBI_PMU_HW_INSTRUCTIONS,
+							SBI_PMU_EVENT_TYPE_HW, 0}},
+	[PERF_COUNT_HW_CACHE_REFERENCES]	= {.hw_gen_event = {
+							SBI_PMU_HW_CACHE_REFERENCES,
+							SBI_PMU_EVENT_TYPE_HW, 0}},
+	[PERF_COUNT_HW_CACHE_MISSES]		= {.hw_gen_event = {
+							SBI_PMU_HW_CACHE_MISSES,
+							SBI_PMU_EVENT_TYPE_HW, 0}},
+	[PERF_COUNT_HW_BRANCH_INSTRUCTIONS]	= {.hw_gen_event = {
+							SBI_PMU_HW_BRANCH_INSTRUCTIONS,
+							SBI_PMU_EVENT_TYPE_HW, 0}},
+	[PERF_COUNT_HW_BRANCH_MISSES]		= {.hw_gen_event = {
+							SBI_PMU_HW_BRANCH_MISSES,
+							SBI_PMU_EVENT_TYPE_HW, 0}},
+	[PERF_COUNT_HW_BUS_CYCLES]		= {.hw_gen_event = {
+							SBI_PMU_HW_BUS_CYCLES,
+							SBI_PMU_EVENT_TYPE_HW, 0}},
+	[PERF_COUNT_HW_STALLED_CYCLES_FRONTEND]	= {.hw_gen_event = {
+							SBI_PMU_HW_STALLED_CYCLES_FRONTEND,
+							SBI_PMU_EVENT_TYPE_HW, 0}},
+	[PERF_COUNT_HW_STALLED_CYCLES_BACKEND]	= {.hw_gen_event = {
+							SBI_PMU_HW_STALLED_CYCLES_BACKEND,
+							SBI_PMU_EVENT_TYPE_HW, 0}},
+	[PERF_COUNT_HW_REF_CPU_CYCLES]		= {.hw_gen_event = {
+							SBI_PMU_HW_REF_CPU_CYCLES,
+							SBI_PMU_EVENT_TYPE_HW, 0}},
+};
+
+#define C(x) PERF_COUNT_HW_CACHE_##x
+static const struct sbi_pmu_event_data pmu_cache_event_map[PERF_COUNT_HW_CACHE_MAX]
+[PERF_COUNT_HW_CACHE_OP_MAX]
+[PERF_COUNT_HW_CACHE_RESULT_MAX] = {
+	[C(L1D)] = {
+		[C(OP_READ)] = {
+			[C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS),
+					C(OP_READ), C(L1D), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+			[C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS),
+					C(OP_READ), C(L1D), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+		},
+		[C(OP_WRITE)] = {
+			[C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS),
+					C(OP_WRITE), C(L1D), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+			[C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS),
+					C(OP_WRITE), C(L1D), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+		},
+		[C(OP_PREFETCH)] = {
+			[C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS),
+					C(OP_PREFETCH), C(L1D), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+			[C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS),
+					C(OP_PREFETCH), C(L1D), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+		},
+	},
+	[C(L1I)] = {
+		[C(OP_READ)] = {
+			[C(RESULT_ACCESS)] = {.hw_cache_event =	{C(RESULT_ACCESS),
+					C(OP_READ), C(L1I), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+			[C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS), C(OP_READ),
+					C(L1I), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+		},
+		[C(OP_WRITE)] = {
+			[C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS),
+					C(OP_WRITE), C(L1I), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+			[C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS),
+					C(OP_WRITE), C(L1I), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+		},
+		[C(OP_PREFETCH)] = {
+			[C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS),
+					C(OP_PREFETCH), C(L1I), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+			[C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS),
+					C(OP_PREFETCH), C(L1I), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+		},
+	},
+	[C(LL)] = {
+		[C(OP_READ)] = {
+			[C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS),
+					C(OP_READ), C(LL), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+			[C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS),
+					C(OP_READ), C(LL), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+		},
+		[C(OP_WRITE)] = {
+			[C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS),
+					C(OP_WRITE), C(LL), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+			[C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS),
+					C(OP_WRITE), C(LL), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+		},
+		[C(OP_PREFETCH)] = {
+			[C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS),
+					C(OP_PREFETCH), C(LL), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+			[C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS),
+					C(OP_PREFETCH), C(LL), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+		},
+	},
+	[C(DTLB)] = {
+		[C(OP_READ)] = {
+			[C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS),
+					C(OP_READ), C(DTLB), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+			[C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS),
+					C(OP_READ), C(DTLB), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+		},
+		[C(OP_WRITE)] = {
+			[C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS),
+					C(OP_WRITE), C(DTLB), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+			[C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS),
+					C(OP_WRITE), C(DTLB), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+		},
+		[C(OP_PREFETCH)] = {
+			[C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS),
+					C(OP_PREFETCH), C(DTLB), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+			[C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS),
+					C(OP_PREFETCH), C(DTLB), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+		},
+	},
+	[C(ITLB)] = {
+		[C(OP_READ)] = {
+			[C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS),
+					C(OP_READ), C(ITLB), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+			[C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS),
+					C(OP_READ), C(ITLB), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+		},
+		[C(OP_WRITE)] = {
+			[C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS),
+					C(OP_WRITE), C(ITLB), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+			[C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS),
+					C(OP_WRITE), C(ITLB), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+		},
+		[C(OP_PREFETCH)] = {
+			[C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS),
+					C(OP_PREFETCH), C(ITLB), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+			[C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS),
+					C(OP_PREFETCH), C(ITLB), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+		},
+	},
+	[C(BPU)] = {
+		[C(OP_READ)] = {
+			[C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS),
+					C(OP_READ), C(BPU), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+			[C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS),
+					C(OP_READ), C(BPU), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+		},
+		[C(OP_WRITE)] = {
+			[C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS),
+					C(OP_WRITE), C(BPU), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+			[C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS),
+					C(OP_WRITE), C(BPU), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+		},
+		[C(OP_PREFETCH)] = {
+			[C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS),
+					C(OP_PREFETCH), C(BPU), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+			[C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS),
+					C(OP_PREFETCH), C(BPU), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+		},
+	},
+	[C(NODE)] = {
+		[C(OP_READ)] = {
+			[C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS),
+					C(OP_READ), C(NODE), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+			[C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS),
+					C(OP_READ), C(NODE), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+		},
+		[C(OP_WRITE)] = {
+			[C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS),
+					C(OP_WRITE), C(NODE), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+			[C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS),
+					C(OP_WRITE), C(NODE), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+		},
+		[C(OP_PREFETCH)] = {
+			[C(RESULT_ACCESS)] = {.hw_cache_event = {C(RESULT_ACCESS),
+					C(OP_PREFETCH), C(NODE), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+			[C(RESULT_MISS)] = {.hw_cache_event = {C(RESULT_MISS),
+					C(OP_PREFETCH), C(NODE), SBI_PMU_EVENT_TYPE_CACHE, 0}},
+		},
+	},
+};
+
+static int pmu_sbi_ctr_get_width(int idx)
+{
+	return pmu_ctr_list[idx].width;
+}
+
+static bool pmu_sbi_ctr_is_fw(int cidx)
+{
+	union sbi_pmu_ctr_info *info;
+
+	info = &pmu_ctr_list[cidx];
+	if (!info)
+		return false;
+
+	return (info->type == SBI_PMU_CTR_TYPE_FW) ? true : false;
+}
+
+static int pmu_sbi_ctr_get_idx(struct perf_event *event)
+{
+	struct hw_perf_event *hwc = &event->hw;
+	struct riscv_pmu *rvpmu = to_riscv_pmu(event->pmu);
+	struct cpu_hw_events *cpuc = this_cpu_ptr(rvpmu->hw_events);
+	struct sbiret ret;
+	int idx;
+	uint64_t cbase = 0;
+	uint64_t cmask = GENMASK_ULL(rvpmu->num_counters - 1, 0);
+	unsigned long cflags = 0;
+
+	if (event->attr.exclude_kernel)
+		cflags |= SBI_PMU_CFG_FLAG_SET_SINH;
+	if (event->attr.exclude_user)
+		cflags |= SBI_PMU_CFG_FLAG_SET_UINH;
+
+	/* retrieve the available counter index */
+	ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_CFG_MATCH, cbase, cmask,
+			cflags, hwc->event_base, hwc->config, 0);
+	if (ret.error) {
+		pr_debug("Not able to find a counter for event %lx config %llx\n",
+			hwc->event_base, hwc->config);
+		return sbi_err_map_linux_errno(ret.error);
+	}
+
+	idx = ret.value;
+	if (idx >= rvpmu->num_counters || !pmu_ctr_list[idx].value)
+		return -ENOENT;
+
+	/* Additional sanity check for the counter id */
+	if (pmu_sbi_ctr_is_fw(idx)) {
+		if (!test_and_set_bit(idx, cpuc->used_fw_ctrs))
+			return idx;
+	} else {
+		if (!test_and_set_bit(idx, cpuc->used_hw_ctrs))
+			return idx;
+	}
+
+	return -ENOENT;
+}
+
+static void pmu_sbi_ctr_clear_idx(struct perf_event *event)
+{
+
+	struct hw_perf_event *hwc = &event->hw;
+	struct riscv_pmu *rvpmu = to_riscv_pmu(event->pmu);
+	struct cpu_hw_events *cpuc = this_cpu_ptr(rvpmu->hw_events);
+	int idx = hwc->idx;
+
+	if (pmu_sbi_ctr_is_fw(idx))
+		clear_bit(idx, cpuc->used_fw_ctrs);
+	else
+		clear_bit(idx, cpuc->used_hw_ctrs);
+}
+
+static int pmu_event_find_cache(u64 config)
+{
+	unsigned int cache_type, cache_op, cache_result, ret;
+
+	cache_type = (config >>  0) & 0xff;
+	if (cache_type >= PERF_COUNT_HW_CACHE_MAX)
+		return -EINVAL;
+
+	cache_op = (config >>  8) & 0xff;
+	if (cache_op >= PERF_COUNT_HW_CACHE_OP_MAX)
+		return -EINVAL;
+
+	cache_result = (config >> 16) & 0xff;
+	if (cache_result >= PERF_COUNT_HW_CACHE_RESULT_MAX)
+		return -EINVAL;
+
+	ret = pmu_cache_event_map[cache_type][cache_op][cache_result].event_idx;
+
+	return ret;
+}
+
+static bool pmu_sbi_is_fw_event(struct perf_event *event)
+{
+	u32 type = event->attr.type;
+	u64 config = event->attr.config;
+
+	if ((type == PERF_TYPE_RAW) && ((config >> 63) == 1))
+		return true;
+	else
+		return false;
+}
+
+static int pmu_sbi_event_map(struct perf_event *event, u64 *econfig)
+{
+	u32 type = event->attr.type;
+	u64 config = event->attr.config;
+	int bSoftware;
+	u64 raw_config_val;
+	int ret;
+
+	switch (type) {
+	case PERF_TYPE_HARDWARE:
+		if (config >= PERF_COUNT_HW_MAX)
+			return -EINVAL;
+		ret = pmu_hw_event_map[event->attr.config].event_idx;
+		break;
+	case PERF_TYPE_HW_CACHE:
+		ret = pmu_event_find_cache(config);
+		break;
+	case PERF_TYPE_RAW:
+		/*
+		 * As per SBI specification, the upper 16 bits must be unused for
+		 * a raw event. Use the MSB (63b) to distinguish between hardware
+		 * raw event and firmware events.
+		 */
+		bSoftware = config >> 63;
+		raw_config_val = config & RISCV_PMU_RAW_EVENT_MASK;
+		if (bSoftware) {
+			if (raw_config_val < SBI_PMU_FW_MAX)
+				ret = (raw_config_val & 0xFFFF) |
+				      (SBI_PMU_EVENT_TYPE_FW << 16);
+			else
+				return -EINVAL;
+		} else {
+			ret = RISCV_PMU_RAW_EVENT_IDX;
+			*econfig = raw_config_val;
+		}
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	return ret;
+}
+
+static u64 pmu_sbi_ctr_read(struct perf_event *event)
+{
+	struct hw_perf_event *hwc = &event->hw;
+	int idx = hwc->idx;
+	struct sbiret ret;
+	union sbi_pmu_ctr_info info;
+	u64 val = 0;
+
+	if (pmu_sbi_is_fw_event(event)) {
+		ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_FW_READ,
+				hwc->idx, 0, 0, 0, 0, 0);
+		if (!ret.error)
+			val = ret.value;
+	} else {
+		info = pmu_ctr_list[idx];
+		val = riscv_pmu_ctr_read_csr(info.csr);
+		if (IS_ENABLED(CONFIG_32BIT))
+			val = ((u64)riscv_pmu_ctr_read_csr(info.csr + 0x80)) << 31 | val;
+	}
+
+	return val;
+}
+
+static void pmu_sbi_ctr_start(struct perf_event *event, u64 ival)
+{
+	struct sbiret ret;
+	struct hw_perf_event *hwc = &event->hw;
+	unsigned long flag = SBI_PMU_START_FLAG_SET_INIT_VALUE;
+
+	ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_START, hwc->idx,
+			1, flag, ival, ival >> 32, 0);
+	if (ret.error && (ret.error != SBI_ERR_ALREADY_STARTED))
+		pr_err("Starting counter idx %d failed with error %d\n",
+			hwc->idx, sbi_err_map_linux_errno(ret.error));
+}
+
+static void pmu_sbi_ctr_stop(struct perf_event *event, unsigned long flag)
+{
+	struct sbiret ret;
+	struct hw_perf_event *hwc = &event->hw;
+
+	ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_STOP, hwc->idx, 1, flag, 0, 0, 0);
+	if (ret.error && (ret.error != SBI_ERR_ALREADY_STOPPED) &&
+		flag != SBI_PMU_STOP_FLAG_RESET)
+		pr_err("Stopping counter idx %d failed with error %d\n",
+			hwc->idx, sbi_err_map_linux_errno(ret.error));
+}
+
+static int pmu_sbi_find_num_ctrs(void)
+{
+	struct sbiret ret;
+
+	ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_NUM_COUNTERS, 0, 0, 0, 0, 0, 0);
+	if (!ret.error)
+		return ret.value;
+	else
+		return sbi_err_map_linux_errno(ret.error);
+}
+
+static int pmu_sbi_get_ctrinfo(int nctr)
+{
+	struct sbiret ret;
+	int i, num_hw_ctr = 0, num_fw_ctr = 0;
+	union sbi_pmu_ctr_info cinfo;
+
+	pmu_ctr_list = kcalloc(nctr, sizeof(*pmu_ctr_list), GFP_KERNEL);
+	if (!pmu_ctr_list)
+		return -ENOMEM;
+
+	for (i = 0; i <= nctr; i++) {
+		ret = sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_GET_INFO, i, 0, 0, 0, 0, 0);
+		if (ret.error)
+			/* The logical counter ids are not expected to be contiguous */
+			continue;
+		cinfo.value = ret.value;
+		if (cinfo.type == SBI_PMU_CTR_TYPE_FW)
+			num_fw_ctr++;
+		else
+			num_hw_ctr++;
+		pmu_ctr_list[i].value = cinfo.value;
+	}
+
+	pr_info("%d firmware and %d hardware counters\n", num_fw_ctr, num_hw_ctr);
+
+	return 0;
+}
+
+static inline void pmu_sbi_stop_all(struct riscv_pmu *pmu)
+{
+	/**
+	 * No need to check the error because we are disabling all the counters
+	 * which may include counters that are not enabled yet.
+	 */
+	sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_STOP,
+		  0, GENMASK_ULL(pmu->num_counters - 1, 0), 0, 0, 0, 0);
+}
+
+static inline void pmu_sbi_stop_hw_ctrs(struct riscv_pmu *pmu)
+{
+	struct cpu_hw_events *cpu_hw_evt = this_cpu_ptr(pmu->hw_events);
+
+	/* No need to check the error here as we can't do anything about the error */
+	sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_STOP, 0,
+		  cpu_hw_evt->used_hw_ctrs[0], 0, 0, 0, 0);
+}
+
+/**
+ * This function starts all the used counters in two step approach.
+ * Any counter that did not overflow can be start in a single step
+ * while the overflowed counters need to be started with updated initialization
+ * value.
+ */
+static inline void pmu_sbi_start_overflow_mask(struct riscv_pmu *pmu,
+					       unsigned long ctr_ovf_mask)
+{
+	int idx = 0;
+	struct cpu_hw_events *cpu_hw_evt = this_cpu_ptr(pmu->hw_events);
+	struct perf_event *event;
+	unsigned long flag = SBI_PMU_START_FLAG_SET_INIT_VALUE;
+	unsigned long ctr_start_mask = 0;
+	uint64_t max_period;
+	struct hw_perf_event *hwc;
+	u64 init_val = 0;
+
+	ctr_start_mask = cpu_hw_evt->used_hw_ctrs[0] & ~ctr_ovf_mask;
+
+	/* Start all the counters that did not overflow in a single shot */
+	sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_START, 0, ctr_start_mask,
+		  0, 0, 0, 0);
+
+	/* Reinitialize and start all the counter that overflowed */
+	while (ctr_ovf_mask) {
+		if (ctr_ovf_mask & 0x01) {
+			event = cpu_hw_evt->events[idx];
+			hwc = &event->hw;
+			max_period = riscv_pmu_ctr_get_width_mask(event);
+			init_val = local64_read(&hwc->prev_count) & max_period;
+			sbi_ecall(SBI_EXT_PMU, SBI_EXT_PMU_COUNTER_START, idx, 1,
+				  flag, init_val, 0, 0);
+		}
+		ctr_ovf_mask = ctr_ovf_mask >> 1;
+		idx++;
+	}
+}
+
+static irqreturn_t pmu_sbi_ovf_handler(int irq, void *dev)
+{
+	struct perf_sample_data data;
+	struct pt_regs *regs;
+	struct hw_perf_event *hw_evt;
+	union sbi_pmu_ctr_info *info;
+	int lidx, hidx, fidx;
+	struct riscv_pmu *pmu;
+	struct perf_event *event;
+	unsigned long overflow;
+	unsigned long overflowed_ctrs = 0;
+	struct cpu_hw_events *cpu_hw_evt = dev;
+
+	if (WARN_ON_ONCE(!cpu_hw_evt))
+		return IRQ_NONE;
+
+	/* Firmware counter don't support overflow yet */
+	fidx = find_first_bit(cpu_hw_evt->used_hw_ctrs, RISCV_MAX_COUNTERS);
+	event = cpu_hw_evt->events[fidx];
+	if (!event) {
+		csr_clear(CSR_SIP, SIP_LCOFIP);
+		return IRQ_NONE;
+	}
+
+	pmu = to_riscv_pmu(event->pmu);
+	pmu_sbi_stop_hw_ctrs(pmu);
+
+	/* Overflow status register should only be read after counter are stopped */
+	overflow = csr_read(CSR_SSCOUNTOVF);
+
+	/**
+	 * Overflow interrupt pending bit should only be cleared after stopping
+	 * all the counters to avoid any race condition.
+	 */
+	csr_clear(CSR_SIP, SIP_LCOFIP);
+
+	/* No overflow bit is set */
+	if (!overflow)
+		return IRQ_NONE;
+
+	regs = get_irq_regs();
+
+	for_each_set_bit(lidx, cpu_hw_evt->used_hw_ctrs, RISCV_MAX_COUNTERS) {
+		struct perf_event *event = cpu_hw_evt->events[lidx];
+
+		/* Skip if invalid event or user did not request a sampling */
+		if (!event || !is_sampling_event(event))
+			continue;
+
+		info = &pmu_ctr_list[lidx];
+		/* Do a sanity check */
+		if (!info || info->type != SBI_PMU_CTR_TYPE_HW)
+			continue;
+
+		/* compute hardware counter index */
+		hidx = info->csr - CSR_CYCLE;
+		/* check if the corresponding bit is set in sscountovf */
+		if (!(overflow & (1 << hidx)))
+			continue;
+
+		/*
+		 * Keep a track of overflowed counters so that they can be started
+		 * with updated initial value.
+		 */
+		overflowed_ctrs |= 1 << lidx;
+		hw_evt = &event->hw;
+		riscv_pmu_event_update(event);
+		perf_sample_data_init(&data, 0, hw_evt->last_period);
+		if (riscv_pmu_event_set_period(event)) {
+			/*
+			 * Unlike other ISAs, RISC-V don't have to disable interrupts
+			 * to avoid throttling here. As per the specification, the
+			 * interrupt remains disabled until the OF bit is set.
+			 * Interrupts are enabled again only during the start.
+			 * TODO: We will need to stop the guest counters once
+			 * virtualization support is added.
+			 */
+			perf_event_overflow(event, &data, regs);
+		}
+	}
+	pmu_sbi_start_overflow_mask(pmu, overflowed_ctrs);
+
+	return IRQ_HANDLED;
+}
+
+static int pmu_sbi_starting_cpu(unsigned int cpu, struct hlist_node *node)
+{
+	struct riscv_pmu *pmu = hlist_entry_safe(node, struct riscv_pmu, node);
+	struct cpu_hw_events *cpu_hw_evt = this_cpu_ptr(pmu->hw_events);
+
+	/* Enable the access for TIME csr only from the user mode now */
+	csr_write(CSR_SCOUNTEREN, 0x2);
+
+	/* Stop all the counters so that they can be enabled from perf */
+	pmu_sbi_stop_all(pmu);
+
+	if (riscv_isa_extension_available(NULL, SSCOFPMF)) {
+		cpu_hw_evt->irq = riscv_pmu_irq;
+		csr_clear(CSR_IP, BIT(RV_IRQ_PMU));
+		csr_set(CSR_IE, BIT(RV_IRQ_PMU));
+		enable_percpu_irq(riscv_pmu_irq, IRQ_TYPE_NONE);
+	}
+
+	return 0;
+}
+
+static int pmu_sbi_dying_cpu(unsigned int cpu, struct hlist_node *node)
+{
+	if (riscv_isa_extension_available(NULL, SSCOFPMF)) {
+		disable_percpu_irq(riscv_pmu_irq);
+		csr_clear(CSR_IE, BIT(RV_IRQ_PMU));
+	}
+
+	/* Disable all counters access for user mode now */
+	csr_write(CSR_SCOUNTEREN, 0x0);
+
+	return 0;
+}
+
+static int pmu_sbi_setup_irqs(struct riscv_pmu *pmu, struct platform_device *pdev)
+{
+	int ret;
+	struct cpu_hw_events __percpu *hw_events = pmu->hw_events;
+	struct device_node *cpu, *child;
+	struct irq_domain *domain = NULL;
+
+	if (!riscv_isa_extension_available(NULL, SSCOFPMF))
+		return -EOPNOTSUPP;
+
+	for_each_of_cpu_node(cpu) {
+		child = of_get_compatible_child(cpu, "riscv,cpu-intc");
+		if (!child) {
+			pr_err("Failed to find INTC node\n");
+			return -ENODEV;
+		}
+		domain = irq_find_host(child);
+		of_node_put(child);
+		if (domain)
+			break;
+	}
+	if (!domain) {
+		pr_err("Failed to find INTC IRQ root domain\n");
+		return -ENODEV;
+	}
+
+	riscv_pmu_irq = irq_create_mapping(domain, RV_IRQ_PMU);
+	if (!riscv_pmu_irq) {
+		pr_err("Failed to map PMU interrupt for node\n");
+		return -ENODEV;
+	}
+
+	ret = request_percpu_irq(riscv_pmu_irq, pmu_sbi_ovf_handler, "riscv-pmu", hw_events);
+	if (ret) {
+		pr_err("registering percpu irq failed [%d]\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int pmu_sbi_device_probe(struct platform_device *pdev)
+{
+	struct riscv_pmu *pmu = NULL;
+	int num_counters;
+	int ret = -ENODEV;
+
+	pr_info("SBI PMU extension is available\n");
+	pmu = riscv_pmu_alloc();
+	if (!pmu)
+		return -ENOMEM;
+
+	num_counters = pmu_sbi_find_num_ctrs();
+	if (num_counters < 0) {
+		pr_err("SBI PMU extension doesn't provide any counters\n");
+		goto out_free;
+	}
+
+	/* cache all the information about counters now */
+	if (pmu_sbi_get_ctrinfo(num_counters))
+		goto out_free;
+
+	ret = pmu_sbi_setup_irqs(pmu, pdev);
+	if (ret < 0) {
+		pr_info("Perf sampling/filtering is not supported as sscof extension is not available\n");
+		pmu->pmu.capabilities |= PERF_PMU_CAP_NO_INTERRUPT;
+		pmu->pmu.capabilities |= PERF_PMU_CAP_NO_EXCLUDE;
+	}
+	pmu->num_counters = num_counters;
+	pmu->ctr_start = pmu_sbi_ctr_start;
+	pmu->ctr_stop = pmu_sbi_ctr_stop;
+	pmu->event_map = pmu_sbi_event_map;
+	pmu->ctr_get_idx = pmu_sbi_ctr_get_idx;
+	pmu->ctr_get_width = pmu_sbi_ctr_get_width;
+	pmu->ctr_clear_idx = pmu_sbi_ctr_clear_idx;
+	pmu->ctr_read = pmu_sbi_ctr_read;
+
+	ret = cpuhp_state_add_instance(CPUHP_AP_PERF_RISCV_STARTING, &pmu->node);
+	if (ret)
+		return ret;
+
+	ret = perf_pmu_register(&pmu->pmu, "cpu", PERF_TYPE_RAW);
+	if (ret) {
+		cpuhp_state_remove_instance(CPUHP_AP_PERF_RISCV_STARTING, &pmu->node);
+		return ret;
+	}
+
+	return 0;
+
+out_free:
+	kfree(pmu);
+	return ret;
+}
+
+static struct platform_driver pmu_sbi_driver = {
+	.probe		= pmu_sbi_device_probe,
+	.driver		= {
+		.name	= RISCV_PMU_PDEV_NAME,
+	},
+};
+
+static int __init pmu_sbi_devinit(void)
+{
+	int ret;
+	struct platform_device *pdev;
+
+	if (sbi_spec_version < sbi_mk_version(0, 3) ||
+	    sbi_probe_extension(SBI_EXT_PMU) <= 0) {
+		return 0;
+	}
+
+	ret = cpuhp_setup_state_multi(CPUHP_AP_PERF_RISCV_STARTING,
+				      "perf/riscv/pmu:starting",
+				      pmu_sbi_starting_cpu, pmu_sbi_dying_cpu);
+	if (ret) {
+		pr_err("CPU hotplug notifier could not be registered: %d\n",
+		       ret);
+		return ret;
+	}
+
+	ret = platform_driver_register(&pmu_sbi_driver);
+	if (ret)
+		return ret;
+
+	pdev = platform_device_register_simple(RISCV_PMU_PDEV_NAME, -1, NULL, 0);
+	if (IS_ERR(pdev)) {
+		platform_driver_unregister(&pmu_sbi_driver);
+		return PTR_ERR(pdev);
+	}
+
+	/* Notify legacy implementation that SBI pmu is available*/
+	riscv_pmu_legacy_skip_init();
+
+	return ret;
+}
+device_initcall(pmu_sbi_devinit)
diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
index 411a428ace4d..51c7e4929df7 100644
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -165,6 +165,7 @@ enum cpuhp_state {
 	CPUHP_AP_PERF_ARM_HW_BREAKPOINT_STARTING,
 	CPUHP_AP_PERF_ARM_ACPI_STARTING,
 	CPUHP_AP_PERF_ARM_STARTING,
+	CPUHP_AP_PERF_RISCV_STARTING,
 	CPUHP_AP_ARM_L2X0_STARTING,
 	CPUHP_AP_EXYNOS4_MCT_TIMER_STARTING,
 	CPUHP_AP_ARM_ARCH_TIMER_STARTING,
diff --git a/include/linux/perf/riscv_pmu.h b/include/linux/perf/riscv_pmu.h
new file mode 100644
index 000000000000..46f9b6fe306e
--- /dev/null
+++ b/include/linux/perf/riscv_pmu.h
@@ -0,0 +1,75 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2018 SiFive
+ * Copyright (C) 2018 Andes Technology Corporation
+ * Copyright (C) 2021 Western Digital Corporation or its affiliates.
+ *
+ */
+
+#ifndef _ASM_RISCV_PERF_EVENT_H
+#define _ASM_RISCV_PERF_EVENT_H
+
+#include <linux/perf_event.h>
+#include <linux/ptrace.h>
+#include <linux/interrupt.h>
+
+#ifdef CONFIG_RISCV_PMU
+
+/*
+ * The RISCV_MAX_COUNTERS parameter should be specified.
+ */
+
+#define RISCV_MAX_COUNTERS	64
+#define RISCV_OP_UNSUPP		(-EOPNOTSUPP)
+#define RISCV_PMU_PDEV_NAME	"riscv-pmu"
+#define RISCV_PMU_LEGACY_PDEV_NAME	"riscv-pmu-legacy"
+
+#define RISCV_PMU_STOP_FLAG_RESET 1
+
+struct cpu_hw_events {
+	/* currently enabled events */
+	int			n_events;
+	/* Counter overflow interrupt */
+	int		irq;
+	/* currently enabled events */
+	struct perf_event	*events[RISCV_MAX_COUNTERS];
+	/* currently enabled hardware counters */
+	DECLARE_BITMAP(used_hw_ctrs, RISCV_MAX_COUNTERS);
+	/* currently enabled firmware counters */
+	DECLARE_BITMAP(used_fw_ctrs, RISCV_MAX_COUNTERS);
+};
+
+struct riscv_pmu {
+	struct pmu	pmu;
+	char		*name;
+
+	irqreturn_t	(*handle_irq)(int irq_num, void *dev);
+
+	int		num_counters;
+	u64		(*ctr_read)(struct perf_event *event);
+	int		(*ctr_get_idx)(struct perf_event *event);
+	int		(*ctr_get_width)(int idx);
+	void		(*ctr_clear_idx)(struct perf_event *event);
+	void		(*ctr_start)(struct perf_event *event, u64 init_val);
+	void		(*ctr_stop)(struct perf_event *event, unsigned long flag);
+	int		(*event_map)(struct perf_event *event, u64 *config);
+
+	struct cpu_hw_events	__percpu *hw_events;
+	struct hlist_node	node;
+};
+
+#define to_riscv_pmu(p) (container_of(p, struct riscv_pmu, pmu))
+unsigned long riscv_pmu_ctr_read_csr(unsigned long csr);
+int riscv_pmu_event_set_period(struct perf_event *event);
+uint64_t riscv_pmu_ctr_get_width_mask(struct perf_event *event);
+u64 riscv_pmu_event_update(struct perf_event *event);
+#ifdef CONFIG_RISCV_PMU_LEGACY
+void riscv_pmu_legacy_skip_init(void);
+#else
+static inline void riscv_pmu_legacy_skip_init(void) {};
+#endif
+struct riscv_pmu *riscv_pmu_alloc(void);
+
+#endif /* CONFIG_RISCV_PMU */
+
+#endif /* _ASM_RISCV_PERF_EVENT_H */