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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /arch/arm/kernel/perf_event_v6.c
parentInitial commit. (diff)
downloadlinux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz
linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/arm/kernel/perf_event_v6.c')
-rw-r--r--arch/arm/kernel/perf_event_v6.c590
1 files changed, 590 insertions, 0 deletions
diff --git a/arch/arm/kernel/perf_event_v6.c b/arch/arm/kernel/perf_event_v6.c
new file mode 100644
index 000000000..1ae99deee
--- /dev/null
+++ b/arch/arm/kernel/perf_event_v6.c
@@ -0,0 +1,590 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ARMv6 Performance counter handling code.
+ *
+ * Copyright (C) 2009 picoChip Designs, Ltd., Jamie Iles
+ *
+ * ARMv6 has 2 configurable performance counters and a single cycle counter.
+ * They all share a single reset bit but can be written to zero so we can use
+ * that for a reset.
+ *
+ * The counters can't be individually enabled or disabled so when we remove
+ * one event and replace it with another we could get spurious counts from the
+ * wrong event. However, we can take advantage of the fact that the
+ * performance counters can export events to the event bus, and the event bus
+ * itself can be monitored. This requires that we *don't* export the events to
+ * the event bus. The procedure for disabling a configurable counter is:
+ * - change the counter to count the ETMEXTOUT[0] signal (0x20). This
+ * effectively stops the counter from counting.
+ * - disable the counter's interrupt generation (each counter has it's
+ * own interrupt enable bit).
+ * Once stopped, the counter value can be written as 0 to reset.
+ *
+ * To enable a counter:
+ * - enable the counter's interrupt generation.
+ * - set the new event type.
+ *
+ * Note: the dedicated cycle counter only counts cycles and can't be
+ * enabled/disabled independently of the others. When we want to disable the
+ * cycle counter, we have to just disable the interrupt reporting and start
+ * ignoring that counter. When re-enabling, we have to reset the value and
+ * enable the interrupt.
+ */
+
+#if defined(CONFIG_CPU_V6) || defined(CONFIG_CPU_V6K)
+
+#include <asm/cputype.h>
+#include <asm/irq_regs.h>
+
+#include <linux/of.h>
+#include <linux/perf/arm_pmu.h>
+#include <linux/platform_device.h>
+
+enum armv6_perf_types {
+ ARMV6_PERFCTR_ICACHE_MISS = 0x0,
+ ARMV6_PERFCTR_IBUF_STALL = 0x1,
+ ARMV6_PERFCTR_DDEP_STALL = 0x2,
+ ARMV6_PERFCTR_ITLB_MISS = 0x3,
+ ARMV6_PERFCTR_DTLB_MISS = 0x4,
+ ARMV6_PERFCTR_BR_EXEC = 0x5,
+ ARMV6_PERFCTR_BR_MISPREDICT = 0x6,
+ ARMV6_PERFCTR_INSTR_EXEC = 0x7,
+ ARMV6_PERFCTR_DCACHE_HIT = 0x9,
+ ARMV6_PERFCTR_DCACHE_ACCESS = 0xA,
+ ARMV6_PERFCTR_DCACHE_MISS = 0xB,
+ ARMV6_PERFCTR_DCACHE_WBACK = 0xC,
+ ARMV6_PERFCTR_SW_PC_CHANGE = 0xD,
+ ARMV6_PERFCTR_MAIN_TLB_MISS = 0xF,
+ ARMV6_PERFCTR_EXPL_D_ACCESS = 0x10,
+ ARMV6_PERFCTR_LSU_FULL_STALL = 0x11,
+ ARMV6_PERFCTR_WBUF_DRAINED = 0x12,
+ ARMV6_PERFCTR_CPU_CYCLES = 0xFF,
+ ARMV6_PERFCTR_NOP = 0x20,
+};
+
+enum armv6_counters {
+ ARMV6_CYCLE_COUNTER = 0,
+ ARMV6_COUNTER0,
+ ARMV6_COUNTER1,
+};
+
+/*
+ * The hardware events that we support. We do support cache operations but
+ * we have harvard caches and no way to combine instruction and data
+ * accesses/misses in hardware.
+ */
+static const unsigned armv6_perf_map[PERF_COUNT_HW_MAX] = {
+ PERF_MAP_ALL_UNSUPPORTED,
+ [PERF_COUNT_HW_CPU_CYCLES] = ARMV6_PERFCTR_CPU_CYCLES,
+ [PERF_COUNT_HW_INSTRUCTIONS] = ARMV6_PERFCTR_INSTR_EXEC,
+ [PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = ARMV6_PERFCTR_BR_EXEC,
+ [PERF_COUNT_HW_BRANCH_MISSES] = ARMV6_PERFCTR_BR_MISPREDICT,
+ [PERF_COUNT_HW_STALLED_CYCLES_FRONTEND] = ARMV6_PERFCTR_IBUF_STALL,
+ [PERF_COUNT_HW_STALLED_CYCLES_BACKEND] = ARMV6_PERFCTR_LSU_FULL_STALL,
+};
+
+static const unsigned armv6_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
+ [PERF_COUNT_HW_CACHE_OP_MAX]
+ [PERF_COUNT_HW_CACHE_RESULT_MAX] = {
+ PERF_CACHE_MAP_ALL_UNSUPPORTED,
+
+ /*
+ * The performance counters don't differentiate between read and write
+ * accesses/misses so this isn't strictly correct, but it's the best we
+ * can do. Writes and reads get combined.
+ */
+ [C(L1D)][C(OP_READ)][C(RESULT_ACCESS)] = ARMV6_PERFCTR_DCACHE_ACCESS,
+ [C(L1D)][C(OP_READ)][C(RESULT_MISS)] = ARMV6_PERFCTR_DCACHE_MISS,
+ [C(L1D)][C(OP_WRITE)][C(RESULT_ACCESS)] = ARMV6_PERFCTR_DCACHE_ACCESS,
+ [C(L1D)][C(OP_WRITE)][C(RESULT_MISS)] = ARMV6_PERFCTR_DCACHE_MISS,
+
+ [C(L1I)][C(OP_READ)][C(RESULT_MISS)] = ARMV6_PERFCTR_ICACHE_MISS,
+
+ /*
+ * The ARM performance counters can count micro DTLB misses, micro ITLB
+ * misses and main TLB misses. There isn't an event for TLB misses, so
+ * use the micro misses here and if users want the main TLB misses they
+ * can use a raw counter.
+ */
+ [C(DTLB)][C(OP_READ)][C(RESULT_MISS)] = ARMV6_PERFCTR_DTLB_MISS,
+ [C(DTLB)][C(OP_WRITE)][C(RESULT_MISS)] = ARMV6_PERFCTR_DTLB_MISS,
+
+ [C(ITLB)][C(OP_READ)][C(RESULT_MISS)] = ARMV6_PERFCTR_ITLB_MISS,
+ [C(ITLB)][C(OP_WRITE)][C(RESULT_MISS)] = ARMV6_PERFCTR_ITLB_MISS,
+};
+
+enum armv6mpcore_perf_types {
+ ARMV6MPCORE_PERFCTR_ICACHE_MISS = 0x0,
+ ARMV6MPCORE_PERFCTR_IBUF_STALL = 0x1,
+ ARMV6MPCORE_PERFCTR_DDEP_STALL = 0x2,
+ ARMV6MPCORE_PERFCTR_ITLB_MISS = 0x3,
+ ARMV6MPCORE_PERFCTR_DTLB_MISS = 0x4,
+ ARMV6MPCORE_PERFCTR_BR_EXEC = 0x5,
+ ARMV6MPCORE_PERFCTR_BR_NOTPREDICT = 0x6,
+ ARMV6MPCORE_PERFCTR_BR_MISPREDICT = 0x7,
+ ARMV6MPCORE_PERFCTR_INSTR_EXEC = 0x8,
+ ARMV6MPCORE_PERFCTR_DCACHE_RDACCESS = 0xA,
+ ARMV6MPCORE_PERFCTR_DCACHE_RDMISS = 0xB,
+ ARMV6MPCORE_PERFCTR_DCACHE_WRACCESS = 0xC,
+ ARMV6MPCORE_PERFCTR_DCACHE_WRMISS = 0xD,
+ ARMV6MPCORE_PERFCTR_DCACHE_EVICTION = 0xE,
+ ARMV6MPCORE_PERFCTR_SW_PC_CHANGE = 0xF,
+ ARMV6MPCORE_PERFCTR_MAIN_TLB_MISS = 0x10,
+ ARMV6MPCORE_PERFCTR_EXPL_MEM_ACCESS = 0x11,
+ ARMV6MPCORE_PERFCTR_LSU_FULL_STALL = 0x12,
+ ARMV6MPCORE_PERFCTR_WBUF_DRAINED = 0x13,
+ ARMV6MPCORE_PERFCTR_CPU_CYCLES = 0xFF,
+};
+
+/*
+ * The hardware events that we support. We do support cache operations but
+ * we have harvard caches and no way to combine instruction and data
+ * accesses/misses in hardware.
+ */
+static const unsigned armv6mpcore_perf_map[PERF_COUNT_HW_MAX] = {
+ PERF_MAP_ALL_UNSUPPORTED,
+ [PERF_COUNT_HW_CPU_CYCLES] = ARMV6MPCORE_PERFCTR_CPU_CYCLES,
+ [PERF_COUNT_HW_INSTRUCTIONS] = ARMV6MPCORE_PERFCTR_INSTR_EXEC,
+ [PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = ARMV6MPCORE_PERFCTR_BR_EXEC,
+ [PERF_COUNT_HW_BRANCH_MISSES] = ARMV6MPCORE_PERFCTR_BR_MISPREDICT,
+ [PERF_COUNT_HW_STALLED_CYCLES_FRONTEND] = ARMV6MPCORE_PERFCTR_IBUF_STALL,
+ [PERF_COUNT_HW_STALLED_CYCLES_BACKEND] = ARMV6MPCORE_PERFCTR_LSU_FULL_STALL,
+};
+
+static const unsigned armv6mpcore_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
+ [PERF_COUNT_HW_CACHE_OP_MAX]
+ [PERF_COUNT_HW_CACHE_RESULT_MAX] = {
+ PERF_CACHE_MAP_ALL_UNSUPPORTED,
+
+ [C(L1D)][C(OP_READ)][C(RESULT_ACCESS)] = ARMV6MPCORE_PERFCTR_DCACHE_RDACCESS,
+ [C(L1D)][C(OP_READ)][C(RESULT_MISS)] = ARMV6MPCORE_PERFCTR_DCACHE_RDMISS,
+ [C(L1D)][C(OP_WRITE)][C(RESULT_ACCESS)] = ARMV6MPCORE_PERFCTR_DCACHE_WRACCESS,
+ [C(L1D)][C(OP_WRITE)][C(RESULT_MISS)] = ARMV6MPCORE_PERFCTR_DCACHE_WRMISS,
+
+ [C(L1I)][C(OP_READ)][C(RESULT_MISS)] = ARMV6MPCORE_PERFCTR_ICACHE_MISS,
+
+ /*
+ * The ARM performance counters can count micro DTLB misses, micro ITLB
+ * misses and main TLB misses. There isn't an event for TLB misses, so
+ * use the micro misses here and if users want the main TLB misses they
+ * can use a raw counter.
+ */
+ [C(DTLB)][C(OP_READ)][C(RESULT_MISS)] = ARMV6MPCORE_PERFCTR_DTLB_MISS,
+ [C(DTLB)][C(OP_WRITE)][C(RESULT_MISS)] = ARMV6MPCORE_PERFCTR_DTLB_MISS,
+
+ [C(ITLB)][C(OP_READ)][C(RESULT_MISS)] = ARMV6MPCORE_PERFCTR_ITLB_MISS,
+ [C(ITLB)][C(OP_WRITE)][C(RESULT_MISS)] = ARMV6MPCORE_PERFCTR_ITLB_MISS,
+};
+
+static inline unsigned long
+armv6_pmcr_read(void)
+{
+ u32 val;
+ asm volatile("mrc p15, 0, %0, c15, c12, 0" : "=r"(val));
+ return val;
+}
+
+static inline void
+armv6_pmcr_write(unsigned long val)
+{
+ asm volatile("mcr p15, 0, %0, c15, c12, 0" : : "r"(val));
+}
+
+#define ARMV6_PMCR_ENABLE (1 << 0)
+#define ARMV6_PMCR_CTR01_RESET (1 << 1)
+#define ARMV6_PMCR_CCOUNT_RESET (1 << 2)
+#define ARMV6_PMCR_CCOUNT_DIV (1 << 3)
+#define ARMV6_PMCR_COUNT0_IEN (1 << 4)
+#define ARMV6_PMCR_COUNT1_IEN (1 << 5)
+#define ARMV6_PMCR_CCOUNT_IEN (1 << 6)
+#define ARMV6_PMCR_COUNT0_OVERFLOW (1 << 8)
+#define ARMV6_PMCR_COUNT1_OVERFLOW (1 << 9)
+#define ARMV6_PMCR_CCOUNT_OVERFLOW (1 << 10)
+#define ARMV6_PMCR_EVT_COUNT0_SHIFT 20
+#define ARMV6_PMCR_EVT_COUNT0_MASK (0xFF << ARMV6_PMCR_EVT_COUNT0_SHIFT)
+#define ARMV6_PMCR_EVT_COUNT1_SHIFT 12
+#define ARMV6_PMCR_EVT_COUNT1_MASK (0xFF << ARMV6_PMCR_EVT_COUNT1_SHIFT)
+
+#define ARMV6_PMCR_OVERFLOWED_MASK \
+ (ARMV6_PMCR_COUNT0_OVERFLOW | ARMV6_PMCR_COUNT1_OVERFLOW | \
+ ARMV6_PMCR_CCOUNT_OVERFLOW)
+
+static inline int
+armv6_pmcr_has_overflowed(unsigned long pmcr)
+{
+ return pmcr & ARMV6_PMCR_OVERFLOWED_MASK;
+}
+
+static inline int
+armv6_pmcr_counter_has_overflowed(unsigned long pmcr,
+ enum armv6_counters counter)
+{
+ int ret = 0;
+
+ if (ARMV6_CYCLE_COUNTER == counter)
+ ret = pmcr & ARMV6_PMCR_CCOUNT_OVERFLOW;
+ else if (ARMV6_COUNTER0 == counter)
+ ret = pmcr & ARMV6_PMCR_COUNT0_OVERFLOW;
+ else if (ARMV6_COUNTER1 == counter)
+ ret = pmcr & ARMV6_PMCR_COUNT1_OVERFLOW;
+ else
+ WARN_ONCE(1, "invalid counter number (%d)\n", counter);
+
+ return ret;
+}
+
+static inline u64 armv6pmu_read_counter(struct perf_event *event)
+{
+ struct hw_perf_event *hwc = &event->hw;
+ int counter = hwc->idx;
+ unsigned long value = 0;
+
+ if (ARMV6_CYCLE_COUNTER == counter)
+ asm volatile("mrc p15, 0, %0, c15, c12, 1" : "=r"(value));
+ else if (ARMV6_COUNTER0 == counter)
+ asm volatile("mrc p15, 0, %0, c15, c12, 2" : "=r"(value));
+ else if (ARMV6_COUNTER1 == counter)
+ asm volatile("mrc p15, 0, %0, c15, c12, 3" : "=r"(value));
+ else
+ WARN_ONCE(1, "invalid counter number (%d)\n", counter);
+
+ return value;
+}
+
+static inline void armv6pmu_write_counter(struct perf_event *event, u64 value)
+{
+ struct hw_perf_event *hwc = &event->hw;
+ int counter = hwc->idx;
+
+ if (ARMV6_CYCLE_COUNTER == counter)
+ asm volatile("mcr p15, 0, %0, c15, c12, 1" : : "r"(value));
+ else if (ARMV6_COUNTER0 == counter)
+ asm volatile("mcr p15, 0, %0, c15, c12, 2" : : "r"(value));
+ else if (ARMV6_COUNTER1 == counter)
+ asm volatile("mcr p15, 0, %0, c15, c12, 3" : : "r"(value));
+ else
+ WARN_ONCE(1, "invalid counter number (%d)\n", counter);
+}
+
+static void armv6pmu_enable_event(struct perf_event *event)
+{
+ unsigned long val, mask, evt, flags;
+ struct arm_pmu *cpu_pmu = to_arm_pmu(event->pmu);
+ struct hw_perf_event *hwc = &event->hw;
+ struct pmu_hw_events *events = this_cpu_ptr(cpu_pmu->hw_events);
+ int idx = hwc->idx;
+
+ if (ARMV6_CYCLE_COUNTER == idx) {
+ mask = 0;
+ evt = ARMV6_PMCR_CCOUNT_IEN;
+ } else if (ARMV6_COUNTER0 == idx) {
+ mask = ARMV6_PMCR_EVT_COUNT0_MASK;
+ evt = (hwc->config_base << ARMV6_PMCR_EVT_COUNT0_SHIFT) |
+ ARMV6_PMCR_COUNT0_IEN;
+ } else if (ARMV6_COUNTER1 == idx) {
+ mask = ARMV6_PMCR_EVT_COUNT1_MASK;
+ evt = (hwc->config_base << ARMV6_PMCR_EVT_COUNT1_SHIFT) |
+ ARMV6_PMCR_COUNT1_IEN;
+ } else {
+ WARN_ONCE(1, "invalid counter number (%d)\n", idx);
+ return;
+ }
+
+ /*
+ * Mask out the current event and set the counter to count the event
+ * that we're interested in.
+ */
+ raw_spin_lock_irqsave(&events->pmu_lock, flags);
+ val = armv6_pmcr_read();
+ val &= ~mask;
+ val |= evt;
+ armv6_pmcr_write(val);
+ raw_spin_unlock_irqrestore(&events->pmu_lock, flags);
+}
+
+static irqreturn_t
+armv6pmu_handle_irq(struct arm_pmu *cpu_pmu)
+{
+ unsigned long pmcr = armv6_pmcr_read();
+ struct perf_sample_data data;
+ struct pmu_hw_events *cpuc = this_cpu_ptr(cpu_pmu->hw_events);
+ struct pt_regs *regs;
+ int idx;
+
+ if (!armv6_pmcr_has_overflowed(pmcr))
+ return IRQ_NONE;
+
+ regs = get_irq_regs();
+
+ /*
+ * The interrupts are cleared by writing the overflow flags back to
+ * the control register. All of the other bits don't have any effect
+ * if they are rewritten, so write the whole value back.
+ */
+ armv6_pmcr_write(pmcr);
+
+ for (idx = 0; idx < cpu_pmu->num_events; ++idx) {
+ struct perf_event *event = cpuc->events[idx];
+ struct hw_perf_event *hwc;
+
+ /* Ignore if we don't have an event. */
+ if (!event)
+ continue;
+
+ /*
+ * We have a single interrupt for all counters. Check that
+ * each counter has overflowed before we process it.
+ */
+ if (!armv6_pmcr_counter_has_overflowed(pmcr, idx))
+ continue;
+
+ hwc = &event->hw;
+ armpmu_event_update(event);
+ perf_sample_data_init(&data, 0, hwc->last_period);
+ if (!armpmu_event_set_period(event))
+ continue;
+
+ if (perf_event_overflow(event, &data, regs))
+ cpu_pmu->disable(event);
+ }
+
+ /*
+ * Handle the pending perf events.
+ *
+ * Note: this call *must* be run with interrupts disabled. For
+ * platforms that can have the PMU interrupts raised as an NMI, this
+ * will not work.
+ */
+ irq_work_run();
+
+ return IRQ_HANDLED;
+}
+
+static void armv6pmu_start(struct arm_pmu *cpu_pmu)
+{
+ unsigned long flags, val;
+ struct pmu_hw_events *events = this_cpu_ptr(cpu_pmu->hw_events);
+
+ raw_spin_lock_irqsave(&events->pmu_lock, flags);
+ val = armv6_pmcr_read();
+ val |= ARMV6_PMCR_ENABLE;
+ armv6_pmcr_write(val);
+ raw_spin_unlock_irqrestore(&events->pmu_lock, flags);
+}
+
+static void armv6pmu_stop(struct arm_pmu *cpu_pmu)
+{
+ unsigned long flags, val;
+ struct pmu_hw_events *events = this_cpu_ptr(cpu_pmu->hw_events);
+
+ raw_spin_lock_irqsave(&events->pmu_lock, flags);
+ val = armv6_pmcr_read();
+ val &= ~ARMV6_PMCR_ENABLE;
+ armv6_pmcr_write(val);
+ raw_spin_unlock_irqrestore(&events->pmu_lock, flags);
+}
+
+static int
+armv6pmu_get_event_idx(struct pmu_hw_events *cpuc,
+ struct perf_event *event)
+{
+ struct hw_perf_event *hwc = &event->hw;
+ /* Always place a cycle counter into the cycle counter. */
+ if (ARMV6_PERFCTR_CPU_CYCLES == hwc->config_base) {
+ if (test_and_set_bit(ARMV6_CYCLE_COUNTER, cpuc->used_mask))
+ return -EAGAIN;
+
+ return ARMV6_CYCLE_COUNTER;
+ } else {
+ /*
+ * For anything other than a cycle counter, try and use
+ * counter0 and counter1.
+ */
+ if (!test_and_set_bit(ARMV6_COUNTER1, cpuc->used_mask))
+ return ARMV6_COUNTER1;
+
+ if (!test_and_set_bit(ARMV6_COUNTER0, cpuc->used_mask))
+ return ARMV6_COUNTER0;
+
+ /* The counters are all in use. */
+ return -EAGAIN;
+ }
+}
+
+static void armv6pmu_clear_event_idx(struct pmu_hw_events *cpuc,
+ struct perf_event *event)
+{
+ clear_bit(event->hw.idx, cpuc->used_mask);
+}
+
+static void armv6pmu_disable_event(struct perf_event *event)
+{
+ unsigned long val, mask, evt, flags;
+ struct arm_pmu *cpu_pmu = to_arm_pmu(event->pmu);
+ struct hw_perf_event *hwc = &event->hw;
+ struct pmu_hw_events *events = this_cpu_ptr(cpu_pmu->hw_events);
+ int idx = hwc->idx;
+
+ if (ARMV6_CYCLE_COUNTER == idx) {
+ mask = ARMV6_PMCR_CCOUNT_IEN;
+ evt = 0;
+ } else if (ARMV6_COUNTER0 == idx) {
+ mask = ARMV6_PMCR_COUNT0_IEN | ARMV6_PMCR_EVT_COUNT0_MASK;
+ evt = ARMV6_PERFCTR_NOP << ARMV6_PMCR_EVT_COUNT0_SHIFT;
+ } else if (ARMV6_COUNTER1 == idx) {
+ mask = ARMV6_PMCR_COUNT1_IEN | ARMV6_PMCR_EVT_COUNT1_MASK;
+ evt = ARMV6_PERFCTR_NOP << ARMV6_PMCR_EVT_COUNT1_SHIFT;
+ } else {
+ WARN_ONCE(1, "invalid counter number (%d)\n", idx);
+ return;
+ }
+
+ /*
+ * Mask out the current event and set the counter to count the number
+ * of ETM bus signal assertion cycles. The external reporting should
+ * be disabled and so this should never increment.
+ */
+ raw_spin_lock_irqsave(&events->pmu_lock, flags);
+ val = armv6_pmcr_read();
+ val &= ~mask;
+ val |= evt;
+ armv6_pmcr_write(val);
+ raw_spin_unlock_irqrestore(&events->pmu_lock, flags);
+}
+
+static void armv6mpcore_pmu_disable_event(struct perf_event *event)
+{
+ unsigned long val, mask, flags, evt = 0;
+ struct arm_pmu *cpu_pmu = to_arm_pmu(event->pmu);
+ struct hw_perf_event *hwc = &event->hw;
+ struct pmu_hw_events *events = this_cpu_ptr(cpu_pmu->hw_events);
+ int idx = hwc->idx;
+
+ if (ARMV6_CYCLE_COUNTER == idx) {
+ mask = ARMV6_PMCR_CCOUNT_IEN;
+ } else if (ARMV6_COUNTER0 == idx) {
+ mask = ARMV6_PMCR_COUNT0_IEN;
+ } else if (ARMV6_COUNTER1 == idx) {
+ mask = ARMV6_PMCR_COUNT1_IEN;
+ } else {
+ WARN_ONCE(1, "invalid counter number (%d)\n", idx);
+ return;
+ }
+
+ /*
+ * Unlike UP ARMv6, we don't have a way of stopping the counters. We
+ * simply disable the interrupt reporting.
+ */
+ raw_spin_lock_irqsave(&events->pmu_lock, flags);
+ val = armv6_pmcr_read();
+ val &= ~mask;
+ val |= evt;
+ armv6_pmcr_write(val);
+ raw_spin_unlock_irqrestore(&events->pmu_lock, flags);
+}
+
+static int armv6_map_event(struct perf_event *event)
+{
+ return armpmu_map_event(event, &armv6_perf_map,
+ &armv6_perf_cache_map, 0xFF);
+}
+
+static void armv6pmu_init(struct arm_pmu *cpu_pmu)
+{
+ cpu_pmu->handle_irq = armv6pmu_handle_irq;
+ cpu_pmu->enable = armv6pmu_enable_event;
+ cpu_pmu->disable = armv6pmu_disable_event;
+ cpu_pmu->read_counter = armv6pmu_read_counter;
+ cpu_pmu->write_counter = armv6pmu_write_counter;
+ cpu_pmu->get_event_idx = armv6pmu_get_event_idx;
+ cpu_pmu->clear_event_idx = armv6pmu_clear_event_idx;
+ cpu_pmu->start = armv6pmu_start;
+ cpu_pmu->stop = armv6pmu_stop;
+ cpu_pmu->map_event = armv6_map_event;
+ cpu_pmu->num_events = 3;
+}
+
+static int armv6_1136_pmu_init(struct arm_pmu *cpu_pmu)
+{
+ armv6pmu_init(cpu_pmu);
+ cpu_pmu->name = "armv6_1136";
+ return 0;
+}
+
+static int armv6_1156_pmu_init(struct arm_pmu *cpu_pmu)
+{
+ armv6pmu_init(cpu_pmu);
+ cpu_pmu->name = "armv6_1156";
+ return 0;
+}
+
+static int armv6_1176_pmu_init(struct arm_pmu *cpu_pmu)
+{
+ armv6pmu_init(cpu_pmu);
+ cpu_pmu->name = "armv6_1176";
+ return 0;
+}
+
+/*
+ * ARMv6mpcore is almost identical to single core ARMv6 with the exception
+ * that some of the events have different enumerations and that there is no
+ * *hack* to stop the programmable counters. To stop the counters we simply
+ * disable the interrupt reporting and update the event. When unthrottling we
+ * reset the period and enable the interrupt reporting.
+ */
+
+static int armv6mpcore_map_event(struct perf_event *event)
+{
+ return armpmu_map_event(event, &armv6mpcore_perf_map,
+ &armv6mpcore_perf_cache_map, 0xFF);
+}
+
+static int armv6mpcore_pmu_init(struct arm_pmu *cpu_pmu)
+{
+ cpu_pmu->name = "armv6_11mpcore";
+ cpu_pmu->handle_irq = armv6pmu_handle_irq;
+ cpu_pmu->enable = armv6pmu_enable_event;
+ cpu_pmu->disable = armv6mpcore_pmu_disable_event;
+ cpu_pmu->read_counter = armv6pmu_read_counter;
+ cpu_pmu->write_counter = armv6pmu_write_counter;
+ cpu_pmu->get_event_idx = armv6pmu_get_event_idx;
+ cpu_pmu->clear_event_idx = armv6pmu_clear_event_idx;
+ cpu_pmu->start = armv6pmu_start;
+ cpu_pmu->stop = armv6pmu_stop;
+ cpu_pmu->map_event = armv6mpcore_map_event;
+ cpu_pmu->num_events = 3;
+
+ return 0;
+}
+
+static const struct of_device_id armv6_pmu_of_device_ids[] = {
+ {.compatible = "arm,arm11mpcore-pmu", .data = armv6mpcore_pmu_init},
+ {.compatible = "arm,arm1176-pmu", .data = armv6_1176_pmu_init},
+ {.compatible = "arm,arm1136-pmu", .data = armv6_1136_pmu_init},
+ { /* sentinel value */ }
+};
+
+static const struct pmu_probe_info armv6_pmu_probe_table[] = {
+ ARM_PMU_PROBE(ARM_CPU_PART_ARM1136, armv6_1136_pmu_init),
+ ARM_PMU_PROBE(ARM_CPU_PART_ARM1156, armv6_1156_pmu_init),
+ ARM_PMU_PROBE(ARM_CPU_PART_ARM1176, armv6_1176_pmu_init),
+ ARM_PMU_PROBE(ARM_CPU_PART_ARM11MPCORE, armv6mpcore_pmu_init),
+ { /* sentinel value */ }
+};
+
+static int armv6_pmu_device_probe(struct platform_device *pdev)
+{
+ return arm_pmu_device_probe(pdev, armv6_pmu_of_device_ids,
+ armv6_pmu_probe_table);
+}
+
+static struct platform_driver armv6_pmu_driver = {
+ .driver = {
+ .name = "armv6-pmu",
+ .of_match_table = armv6_pmu_of_device_ids,
+ },
+ .probe = armv6_pmu_device_probe,
+};
+
+builtin_platform_driver(armv6_pmu_driver);
+#endif /* CONFIG_CPU_V6 || CONFIG_CPU_V6K */