diff --git a/arch/arm/kernel/perf_event_v7.c b/arch/arm/kernel/perf_event_v7.c
index e39bc89..0934c82 100644
--- a/arch/arm/kernel/perf_event_v7.c
+++ b/arch/arm/kernel/perf_event_v7.c
@@ -676,23 +676,24 @@ static const unsigned armv7_a15_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
 };
 
 /*
- * Perf Events counters
+ * Perf Events' indices
  */
-enum armv7_counters {
-	ARMV7_CYCLE_COUNTER		= 1,	/* Cycle counter */
-	ARMV7_COUNTER0			= 2,	/* First event counter */
-};
+#define	ARMV7_IDX_CYCLE_COUNTER	0
+#define	ARMV7_IDX_COUNTER0	1
+#define	ARMV7_IDX_COUNTER_LAST	(ARMV7_IDX_CYCLE_COUNTER + armpmu->num_events - 1)
+
+#define	ARMV7_MAX_COUNTERS	32
+#define	ARMV7_COUNTER_MASK	(ARMV7_MAX_COUNTERS - 1)
 
 /*
- * The cycle counter is ARMV7_CYCLE_COUNTER.
- * The first event counter is ARMV7_COUNTER0.
- * The last event counter is (ARMV7_COUNTER0 + armpmu->num_events - 1).
+ * ARMv7 low level PMNC access
  */
-#define	ARMV7_COUNTER_LAST	(ARMV7_COUNTER0 + armpmu->num_events - 1)
 
 /*
- * ARMv7 low level PMNC access
+ * Perf Event to low level counters mapping
  */
+#define	ARMV7_IDX_TO_COUNTER(x)	\
+	(((x) - ARMV7_IDX_COUNTER0) & ARMV7_COUNTER_MASK)
 
 /*
  * Per-CPU PMNC: config reg
@@ -708,53 +709,13 @@ enum armv7_counters {
 #define	ARMV7_PMNC_MASK		0x3f	 /* Mask for writable bits */
 
 /*
- * Available counters
- */
-#define ARMV7_CNT0		0	/* First event counter */
-#define ARMV7_CCNT		31	/* Cycle counter */
-
-/* Perf Event to low level counters mapping */
-#define ARMV7_EVENT_CNT_TO_CNTx	(ARMV7_COUNTER0 - ARMV7_CNT0)
-
-/*
- * CNTENS: counters enable reg
- */
-#define ARMV7_CNTENS_P(idx)	(1 << (idx - ARMV7_EVENT_CNT_TO_CNTx))
-#define ARMV7_CNTENS_C		(1 << ARMV7_CCNT)
-
-/*
- * CNTENC: counters disable reg
- */
-#define ARMV7_CNTENC_P(idx)	(1 << (idx - ARMV7_EVENT_CNT_TO_CNTx))
-#define ARMV7_CNTENC_C		(1 << ARMV7_CCNT)
-
-/*
- * INTENS: counters overflow interrupt enable reg
- */
-#define ARMV7_INTENS_P(idx)	(1 << (idx - ARMV7_EVENT_CNT_TO_CNTx))
-#define ARMV7_INTENS_C		(1 << ARMV7_CCNT)
-
-/*
- * INTENC: counters overflow interrupt disable reg
- */
-#define ARMV7_INTENC_P(idx)	(1 << (idx - ARMV7_EVENT_CNT_TO_CNTx))
-#define ARMV7_INTENC_C		(1 << ARMV7_CCNT)
-
-/*
  * EVTSEL: Event selection reg
  */
 #define	ARMV7_EVTSEL_MASK	0xff		/* Mask for writable bits */
 
 /*
- * SELECT: Counter selection reg
- */
-#define	ARMV7_SELECT_MASK	0x1f		/* Mask for writable bits */
-
-/*
  * FLAG: counters overflow flag status reg
  */
-#define ARMV7_FLAG_P(idx)	(1 << (idx - ARMV7_EVENT_CNT_TO_CNTx))
-#define ARMV7_FLAG_C		(1 << ARMV7_CCNT)
 #define	ARMV7_FLAG_MASK		0xffffffff	/* Mask for writable bits */
 #define	ARMV7_OVERFLOWED_MASK	ARMV7_FLAG_MASK
 
@@ -777,34 +738,39 @@ static inline int armv7_pmnc_has_overflowed(u32 pmnc)
 	return pmnc & ARMV7_OVERFLOWED_MASK;
 }
 
-static inline int armv7_pmnc_counter_has_overflowed(u32 pmnc,
-					enum armv7_counters counter)
+static inline int armv7_pmnc_counter_valid(int idx)
+{
+	return idx >= ARMV7_IDX_CYCLE_COUNTER && idx <= ARMV7_IDX_COUNTER_LAST;
+}
+
+static inline int armv7_pmnc_counter_has_overflowed(u32 pmnc, int idx)
 {
 	int ret = 0;
+	u32 counter;
 
-	if (counter == ARMV7_CYCLE_COUNTER)
-		ret = pmnc & ARMV7_FLAG_C;
-	else if ((counter >= ARMV7_COUNTER0) && (counter <= ARMV7_COUNTER_LAST))
-		ret = pmnc & ARMV7_FLAG_P(counter);
-	else
+	if (!armv7_pmnc_counter_valid(idx)) {
 		pr_err("CPU%u checking wrong counter %d overflow status\n",
-			smp_processor_id(), counter);
+			smp_processor_id(), idx);
+	} else {
+		counter = ARMV7_IDX_TO_COUNTER(idx);
+		ret = pmnc & BIT(counter);
+	}
 
 	return ret;
 }
 
 static inline int armv7_pmnc_select_counter(int idx)
 {
-	u32 val;
+	u32 counter;
 
-	if ((idx < ARMV7_COUNTER0) || (idx > ARMV7_COUNTER_LAST)) {
-		pr_err("CPU%u selecting wrong PMNC counter"
-			" %d\n", smp_processor_id(), idx);
-		return -1;
+	if (!armv7_pmnc_counter_valid(idx)) {
+		pr_err("CPU%u selecting wrong PMNC counter %d\n",
+			smp_processor_id(), idx);
+		return -EINVAL;
 	}
 
-	val = (idx - ARMV7_EVENT_CNT_TO_CNTx) & ARMV7_SELECT_MASK;
-	asm volatile("mcr p15, 0, %0, c9, c12, 5" : : "r" (val));
+	counter = ARMV7_IDX_TO_COUNTER(idx);
+	asm volatile("mcr p15, 0, %0, c9, c12, 5" : : "r" (counter));
 	isb();
 
 	return idx;
@@ -814,30 +780,26 @@ static inline u32 armv7pmu_read_counter(int idx)
 {
 	u32 value = 0;
 
-	if (idx == ARMV7_CYCLE_COUNTER)
-		asm volatile("mrc p15, 0, %0, c9, c13, 0" : "=r" (value));
-	else if ((idx >= ARMV7_COUNTER0) && (idx <= ARMV7_COUNTER_LAST)) {
-		if (armv7_pmnc_select_counter(idx) == idx)
-			asm volatile("mrc p15, 0, %0, c9, c13, 2"
-				     : "=r" (value));
-	} else
+	if (!armv7_pmnc_counter_valid(idx))
 		pr_err("CPU%u reading wrong counter %d\n",
 			smp_processor_id(), idx);
+	else if (idx == ARMV7_IDX_CYCLE_COUNTER)
+		asm volatile("mrc p15, 0, %0, c9, c13, 0" : "=r" (value));
+	else if (armv7_pmnc_select_counter(idx) == idx)
+		asm volatile("mrc p15, 0, %0, c9, c13, 2" : "=r" (value));
 
 	return value;
 }
 
 static inline void armv7pmu_write_counter(int idx, u32 value)
 {
-	if (idx == ARMV7_CYCLE_COUNTER)
-		asm volatile("mcr p15, 0, %0, c9, c13, 0" : : "r" (value));
-	else if ((idx >= ARMV7_COUNTER0) && (idx <= ARMV7_COUNTER_LAST)) {
-		if (armv7_pmnc_select_counter(idx) == idx)
-			asm volatile("mcr p15, 0, %0, c9, c13, 2"
-				     : : "r" (value));
-	} else
+	if (!armv7_pmnc_counter_valid(idx))
 		pr_err("CPU%u writing wrong counter %d\n",
 			smp_processor_id(), idx);
+	else if (idx == ARMV7_IDX_CYCLE_COUNTER)
+		asm volatile("mcr p15, 0, %0, c9, c13, 0" : : "r" (value));
+	else if (armv7_pmnc_select_counter(idx) == idx)
+		asm volatile("mcr p15, 0, %0, c9, c13, 2" : : "r" (value));
 }
 
 static inline void armv7_pmnc_write_evtsel(int idx, u32 val)
@@ -850,86 +812,61 @@ static inline void armv7_pmnc_write_evtsel(int idx, u32 val)
 
 static inline int armv7_pmnc_enable_counter(int idx)
 {
-	u32 val;
+	u32 counter;
 
-	if ((idx != ARMV7_CYCLE_COUNTER) &&
-	    ((idx < ARMV7_COUNTER0) || (idx > ARMV7_COUNTER_LAST))) {
-		pr_err("CPU%u enabling wrong PMNC counter"
-			" %d\n", smp_processor_id(), idx);
-		return -1;
+	if (!armv7_pmnc_counter_valid(idx)) {
+		pr_err("CPU%u enabling wrong PMNC counter %d\n",
+			smp_processor_id(), idx);
+		return -EINVAL;
 	}
 
-	if (idx == ARMV7_CYCLE_COUNTER)
-		val = ARMV7_CNTENS_C;
-	else
-		val = ARMV7_CNTENS_P(idx);
-
-	asm volatile("mcr p15, 0, %0, c9, c12, 1" : : "r" (val));
-
+	counter = ARMV7_IDX_TO_COUNTER(idx);
+	asm volatile("mcr p15, 0, %0, c9, c12, 1" : : "r" (BIT(counter)));
 	return idx;
 }
 
 static inline int armv7_pmnc_disable_counter(int idx)
 {
-	u32 val;
+	u32 counter;
 
-
-	if ((idx != ARMV7_CYCLE_COUNTER) &&
-	    ((idx < ARMV7_COUNTER0) || (idx > ARMV7_COUNTER_LAST))) {
-		pr_err("CPU%u disabling wrong PMNC counter"
-			" %d\n", smp_processor_id(), idx);
-		return -1;
+	if (!armv7_pmnc_counter_valid(idx)) {
+		pr_err("CPU%u disabling wrong PMNC counter %d\n",
+			smp_processor_id(), idx);
+		return -EINVAL;
 	}
 
-	if (idx == ARMV7_CYCLE_COUNTER)
-		val = ARMV7_CNTENC_C;
-	else
-		val = ARMV7_CNTENC_P(idx);
-
-	asm volatile("mcr p15, 0, %0, c9, c12, 2" : : "r" (val));
-
+	counter = ARMV7_IDX_TO_COUNTER(idx);
+	asm volatile("mcr p15, 0, %0, c9, c12, 2" : : "r" (BIT(counter)));
 	return idx;
 }
 
 static inline int armv7_pmnc_enable_intens(int idx)
 {
-	u32 val;
+	u32 counter;
 
-	if ((idx != ARMV7_CYCLE_COUNTER) &&
-	    ((idx < ARMV7_COUNTER0) || (idx > ARMV7_COUNTER_LAST))) {
-		pr_err("CPU%u enabling wrong PMNC counter"
-			" interrupt enable %d\n", smp_processor_id(), idx);
-		return -1;
+	if (!armv7_pmnc_counter_valid(idx)) {
+		pr_err("CPU%u enabling wrong PMNC counter IRQ enable %d\n",
+			smp_processor_id(), idx);
+		return -EINVAL;
 	}
 
-	if (idx == ARMV7_CYCLE_COUNTER)
-		val = ARMV7_INTENS_C;
-	else
-		val = ARMV7_INTENS_P(idx);
-
-	asm volatile("mcr p15, 0, %0, c9, c14, 1" : : "r" (val));
-
+	counter = ARMV7_IDX_TO_COUNTER(idx);
+	asm volatile("mcr p15, 0, %0, c9, c14, 1" : : "r" (BIT(counter)));
 	return idx;
 }
 
 static inline int armv7_pmnc_disable_intens(int idx)
 {
-	u32 val;
+	u32 counter;
 
-	if ((idx != ARMV7_CYCLE_COUNTER) &&
-	    ((idx < ARMV7_COUNTER0) || (idx > ARMV7_COUNTER_LAST))) {
-		pr_err("CPU%u disabling wrong PMNC counter"
-			" interrupt enable %d\n", smp_processor_id(), idx);
-		return -1;
+	if (!armv7_pmnc_counter_valid(idx)) {
+		pr_err("CPU%u disabling wrong PMNC counter IRQ enable %d\n",
+			smp_processor_id(), idx);
+		return -EINVAL;
 	}
 
-	if (idx == ARMV7_CYCLE_COUNTER)
-		val = ARMV7_INTENC_C;
-	else
-		val = ARMV7_INTENC_P(idx);
-
-	asm volatile("mcr p15, 0, %0, c9, c14, 2" : : "r" (val));
-
+	counter = ARMV7_IDX_TO_COUNTER(idx);
+	asm volatile("mcr p15, 0, %0, c9, c14, 2" : : "r" (BIT(counter)));
 	return idx;
 }
 
@@ -973,14 +910,14 @@ static void armv7_pmnc_dump_regs(void)
 	asm volatile("mrc p15, 0, %0, c9, c13, 0" : "=r" (val));
 	printk(KERN_INFO "CCNT  =0x%08x\n", val);
 
-	for (cnt = ARMV7_COUNTER0; cnt < ARMV7_COUNTER_LAST; cnt++) {
+	for (cnt = ARMV7_IDX_COUNTER0; cnt <= ARMV7_IDX_COUNTER_LAST; cnt++) {
 		armv7_pmnc_select_counter(cnt);
 		asm volatile("mrc p15, 0, %0, c9, c13, 2" : "=r" (val));
 		printk(KERN_INFO "CNT[%d] count =0x%08x\n",
-			cnt-ARMV7_EVENT_CNT_TO_CNTx, val);
+			ARMV7_IDX_TO_COUNTER(cnt), val);
 		asm volatile("mrc p15, 0, %0, c9, c13, 1" : "=r" (val));
 		printk(KERN_INFO "CNT[%d] evtsel=0x%08x\n",
-			cnt-ARMV7_EVENT_CNT_TO_CNTx, val);
+			ARMV7_IDX_TO_COUNTER(cnt), val);
 	}
 }
 #endif
@@ -1004,7 +941,7 @@ static void armv7pmu_enable_event(struct hw_perf_event *hwc, int idx)
 	 * Set event (if destined for PMNx counters)
 	 * We don't need to set the event if it's a cycle count
 	 */
-	if (idx != ARMV7_CYCLE_COUNTER)
+	if (idx != ARMV7_IDX_CYCLE_COUNTER)
 		armv7_pmnc_write_evtsel(idx, hwc->config_base);
 
 	/*
@@ -1069,7 +1006,7 @@ static irqreturn_t armv7pmu_handle_irq(int irq_num, void *dev)
 	perf_sample_data_init(&data, 0);
 
 	cpuc = &__get_cpu_var(cpu_hw_events);
-	for (idx = 0; idx <= armpmu->num_events; ++idx) {
+	for (idx = 0; idx < armpmu->num_events; ++idx) {
 		struct perf_event *event = cpuc->events[idx];
 		struct hw_perf_event *hwc;
 
@@ -1132,23 +1069,23 @@ static int armv7pmu_get_event_idx(struct cpu_hw_events *cpuc,
 
 	/* Always place a cycle counter into the cycle counter. */
 	if (event->config_base == ARMV7_PERFCTR_CPU_CYCLES) {
-		if (test_and_set_bit(ARMV7_CYCLE_COUNTER, cpuc->used_mask))
+		if (test_and_set_bit(ARMV7_IDX_CYCLE_COUNTER, cpuc->used_mask))
 			return -EAGAIN;
 
-		return ARMV7_CYCLE_COUNTER;
-	} else {
-		/*
-		 * For anything other than a cycle counter, try and use
-		 * the events counters
-		 */
-		for (idx = ARMV7_COUNTER0; idx <= armpmu->num_events; ++idx) {
-			if (!test_and_set_bit(idx, cpuc->used_mask))
-				return idx;
-		}
+		return ARMV7_IDX_CYCLE_COUNTER;
+	}
 
-		/* The counters are all in use. */
-		return -EAGAIN;
+	/*
+	 * For anything other than a cycle counter, try and use
+	 * the events counters
+	 */
+	for (idx = ARMV7_IDX_COUNTER0; idx < armpmu->num_events; ++idx) {
+		if (!test_and_set_bit(idx, cpuc->used_mask))
+			return idx;
 	}
+
+	/* The counters are all in use. */
+	return -EAGAIN;
 }
 
 static void armv7pmu_reset(void *info)
@@ -1156,7 +1093,7 @@ static void armv7pmu_reset(void *info)
 	u32 idx, nb_cnt = armpmu->num_events;
 
 	/* The counter and interrupt enable registers are unknown at reset. */
-	for (idx = 1; idx < nb_cnt; ++idx)
+	for (idx = ARMV7_IDX_CYCLE_COUNTER; idx < nb_cnt; ++idx)
 		armv7pmu_disable_event(NULL, idx);
 
 	/* Initialize & Reset PMNC: C and P bits */
