diff --git a/arch/arm/boot/dts/tegra20.dtsi b/arch/arm/boot/dts/tegra20.dtsi
index 649391579871..2e7c83c7253b 100644
--- a/arch/arm/boot/dts/tegra20.dtsi
+++ b/arch/arm/boot/dts/tegra20.dtsi
@@ -489,6 +489,23 @@ sdhci@c8000600 {
 		status = "disabled";
 	};
 
+	cpus {
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		cpu@0 {
+			device_type = "cpu";
+			compatible = "arm,cortex-a9";
+			reg = <0>;
+		};
+
+		cpu@1 {
+			device_type = "cpu";
+			compatible = "arm,cortex-a9";
+			reg = <1>;
+		};
+	};
+
 	pmu {
 		compatible = "arm,cortex-a9-pmu";
 		interrupts = <0 56 0x04
diff --git a/arch/arm/boot/dts/tegra30.dtsi b/arch/arm/boot/dts/tegra30.dtsi
index b1483d925878..2de8b919d78c 100644
--- a/arch/arm/boot/dts/tegra30.dtsi
+++ b/arch/arm/boot/dts/tegra30.dtsi
@@ -506,6 +506,35 @@ sdhci@78000600 {
 		status = "disabled";
 	};
 
+	cpus {
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		cpu@0 {
+			device_type = "cpu";
+			compatible = "arm,cortex-a9";
+			reg = <0>;
+		};
+
+		cpu@1 {
+			device_type = "cpu";
+			compatible = "arm,cortex-a9";
+			reg = <1>;
+		};
+
+		cpu@2 {
+			device_type = "cpu";
+			compatible = "arm,cortex-a9";
+			reg = <2>;
+		};
+
+		cpu@3 {
+			device_type = "cpu";
+			compatible = "arm,cortex-a9";
+			reg = <3>;
+		};
+	};
+
 	pmu {
 		compatible = "arm,cortex-a9-pmu";
 		interrupts = <0 144 0x04
diff --git a/arch/arm/include/asm/cputype.h b/arch/arm/include/asm/cputype.h
index a59dcb5ab5fc..ad41ec2471e8 100644
--- a/arch/arm/include/asm/cputype.h
+++ b/arch/arm/include/asm/cputype.h
@@ -64,6 +64,24 @@ extern unsigned int processor_id;
 #define read_cpuid_ext(reg) 0
 #endif
 
+#define ARM_CPU_IMP_ARM			0x41
+#define ARM_CPU_IMP_INTEL		0x69
+
+#define ARM_CPU_PART_ARM1136		0xB360
+#define ARM_CPU_PART_ARM1156		0xB560
+#define ARM_CPU_PART_ARM1176		0xB760
+#define ARM_CPU_PART_ARM11MPCORE	0xB020
+#define ARM_CPU_PART_CORTEX_A8		0xC080
+#define ARM_CPU_PART_CORTEX_A9		0xC090
+#define ARM_CPU_PART_CORTEX_A5		0xC050
+#define ARM_CPU_PART_CORTEX_A15		0xC0F0
+#define ARM_CPU_PART_CORTEX_A7		0xC070
+
+#define ARM_CPU_XSCALE_ARCH_MASK	0xe000
+#define ARM_CPU_XSCALE_ARCH_V1		0x2000
+#define ARM_CPU_XSCALE_ARCH_V2		0x4000
+#define ARM_CPU_XSCALE_ARCH_V3		0x6000
+
 /*
  * The CPU ID never changes at run time, so we might as well tell the
  * compiler that it's constant.  Use this function to read the CPU ID
@@ -74,6 +92,21 @@ static inline unsigned int __attribute_const__ read_cpuid_id(void)
 	return read_cpuid(CPUID_ID);
 }
 
+static inline unsigned int __attribute_const__ read_cpuid_implementor(void)
+{
+	return (read_cpuid_id() & 0xFF000000) >> 24;
+}
+
+static inline unsigned int __attribute_const__ read_cpuid_part_number(void)
+{
+	return read_cpuid_id() & 0xFFF0;
+}
+
+static inline unsigned int __attribute_const__ xscale_cpu_arch_version(void)
+{
+	return read_cpuid_part_number() & ARM_CPU_XSCALE_ARCH_MASK;
+}
+
 static inline unsigned int __attribute_const__ read_cpuid_cachetype(void)
 {
 	return read_cpuid(CPUID_CACHETYPE);
diff --git a/arch/arm/include/asm/smp_scu.h b/arch/arm/include/asm/smp_scu.h
index 4eb6d005ffaa..006f02681cd8 100644
--- a/arch/arm/include/asm/smp_scu.h
+++ b/arch/arm/include/asm/smp_scu.h
@@ -6,6 +6,23 @@
 #define SCU_PM_POWEROFF	3
 
 #ifndef __ASSEMBLER__
+
+#include <asm/cputype.h>
+
+static inline bool scu_a9_has_base(void)
+{
+	return read_cpuid_part_number() == ARM_CPU_PART_CORTEX_A9;
+}
+
+static inline unsigned long scu_a9_get_base(void)
+{
+	unsigned long pa;
+
+	asm("mrc p15, 4, %0, c15, c0, 0" : "=r" (pa));
+
+	return pa;
+}
+
 unsigned int scu_get_core_count(void __iomem *);
 void scu_enable(void __iomem *);
 int scu_power_mode(void __iomem *, unsigned int);
diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c
index f9e8657dd241..31e0eb353cd8 100644
--- a/arch/arm/kernel/perf_event.c
+++ b/arch/arm/kernel/perf_event.c
@@ -149,12 +149,6 @@ u64 armpmu_event_update(struct perf_event *event)
 static void
 armpmu_read(struct perf_event *event)
 {
-	struct hw_perf_event *hwc = &event->hw;
-
-	/* Don't read disabled counters! */
-	if (hwc->idx < 0)
-		return;
-
 	armpmu_event_update(event);
 }
 
@@ -207,8 +201,6 @@ armpmu_del(struct perf_event *event, int flags)
 	struct hw_perf_event *hwc = &event->hw;
 	int idx = hwc->idx;
 
-	WARN_ON(idx < 0);
-
 	armpmu_stop(event, PERF_EF_UPDATE);
 	hw_events->events[idx] = NULL;
 	clear_bit(idx, hw_events->used_mask);
@@ -358,7 +350,7 @@ __hw_perf_event_init(struct perf_event *event)
 {
 	struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
 	struct hw_perf_event *hwc = &event->hw;
-	int mapping, err;
+	int mapping;
 
 	mapping = armpmu->map_event(event);
 
@@ -407,14 +399,12 @@ __hw_perf_event_init(struct perf_event *event)
 		local64_set(&hwc->period_left, hwc->sample_period);
 	}
 
-	err = 0;
 	if (event->group_leader != event) {
-		err = validate_group(event);
-		if (err)
+		if (validate_group(event) != 0);
 			return -EINVAL;
 	}
 
-	return err;
+	return 0;
 }
 
 static int armpmu_event_init(struct perf_event *event)
diff --git a/arch/arm/kernel/perf_event_cpu.c b/arch/arm/kernel/perf_event_cpu.c
index 5f6620684e25..1f2740e3dbc0 100644
--- a/arch/arm/kernel/perf_event_cpu.c
+++ b/arch/arm/kernel/perf_event_cpu.c
@@ -147,7 +147,7 @@ static void cpu_pmu_init(struct arm_pmu *cpu_pmu)
 	cpu_pmu->free_irq	= cpu_pmu_free_irq;
 
 	/* Ensure the PMU has sane values out of reset. */
-	if (cpu_pmu && cpu_pmu->reset)
+	if (cpu_pmu->reset)
 		on_each_cpu(cpu_pmu->reset, cpu_pmu, 1);
 }
 
@@ -201,48 +201,46 @@ static struct platform_device_id cpu_pmu_plat_device_ids[] = {
 static int probe_current_pmu(struct arm_pmu *pmu)
 {
 	int cpu = get_cpu();
-	unsigned long cpuid = read_cpuid_id();
-	unsigned long implementor = (cpuid & 0xFF000000) >> 24;
-	unsigned long part_number = (cpuid & 0xFFF0);
+	unsigned long implementor = read_cpuid_implementor();
+	unsigned long part_number = read_cpuid_part_number();
 	int ret = -ENODEV;
 
 	pr_info("probing PMU on CPU %d\n", cpu);
 
 	/* ARM Ltd CPUs. */
-	if (0x41 == implementor) {
+	if (implementor == ARM_CPU_IMP_ARM) {
 		switch (part_number) {
-		case 0xB360:	/* ARM1136 */
-		case 0xB560:	/* ARM1156 */
-		case 0xB760:	/* ARM1176 */
+		case ARM_CPU_PART_ARM1136:
+		case ARM_CPU_PART_ARM1156:
+		case ARM_CPU_PART_ARM1176:
 			ret = armv6pmu_init(pmu);
 			break;
-		case 0xB020:	/* ARM11mpcore */
+		case ARM_CPU_PART_ARM11MPCORE:
 			ret = armv6mpcore_pmu_init(pmu);
 			break;
-		case 0xC080:	/* Cortex-A8 */
+		case ARM_CPU_PART_CORTEX_A8:
 			ret = armv7_a8_pmu_init(pmu);
 			break;
-		case 0xC090:	/* Cortex-A9 */
+		case ARM_CPU_PART_CORTEX_A9:
 			ret = armv7_a9_pmu_init(pmu);
 			break;
-		case 0xC050:	/* Cortex-A5 */
+		case ARM_CPU_PART_CORTEX_A5:
 			ret = armv7_a5_pmu_init(pmu);
 			break;
-		case 0xC0F0:	/* Cortex-A15 */
+		case ARM_CPU_PART_CORTEX_A15:
 			ret = armv7_a15_pmu_init(pmu);
 			break;
-		case 0xC070:	/* Cortex-A7 */
+		case ARM_CPU_PART_CORTEX_A7:
 			ret = armv7_a7_pmu_init(pmu);
 			break;
 		}
 	/* Intel CPUs [xscale]. */
-	} else if (0x69 == implementor) {
-		part_number = (cpuid >> 13) & 0x7;
-		switch (part_number) {
-		case 1:
+	} else if (implementor == ARM_CPU_IMP_INTEL) {
+		switch (xscale_cpu_arch_version()) {
+		case ARM_CPU_XSCALE_ARCH_V1:
 			ret = xscale1pmu_init(pmu);
 			break;
-		case 2:
+		case ARM_CPU_XSCALE_ARCH_V2:
 			ret = xscale2pmu_init(pmu);
 			break;
 		}
@@ -279,17 +277,22 @@ static int cpu_pmu_device_probe(struct platform_device *pdev)
 	}
 
 	if (ret) {
-		pr_info("failed to register PMU devices!");
-		kfree(pmu);
-		return ret;
+		pr_info("failed to probe PMU!");
+		goto out_free;
 	}
 
 	cpu_pmu = pmu;
 	cpu_pmu->plat_device = pdev;
 	cpu_pmu_init(cpu_pmu);
-	armpmu_register(cpu_pmu, PERF_TYPE_RAW);
+	ret = armpmu_register(cpu_pmu, PERF_TYPE_RAW);
 
-	return 0;
+	if (!ret)
+		return 0;
+
+out_free:
+	pr_info("failed to register PMU devices!");
+	kfree(pmu);
+	return ret;
 }
 
 static struct platform_driver cpu_pmu_driver = {
diff --git a/arch/arm/kernel/perf_event_v6.c b/arch/arm/kernel/perf_event_v6.c
index 041d0526a288..03664b0e8fa4 100644
--- a/arch/arm/kernel/perf_event_v6.c
+++ b/arch/arm/kernel/perf_event_v6.c
@@ -106,7 +106,7 @@ static const unsigned armv6_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
 		},
 		[C(OP_WRITE)] = {
 			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
-			[C(RESULT_MISS)]	= ARMV6_PERFCTR_ICACHE_MISS,
+			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
 		},
 		[C(OP_PREFETCH)] = {
 			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
@@ -259,7 +259,7 @@ static const unsigned armv6mpcore_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
 		},
 		[C(OP_WRITE)] = {
 			[C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
-			[C(RESULT_MISS)]    = ARMV6MPCORE_PERFCTR_ICACHE_MISS,
+			[C(RESULT_MISS)]    = CACHE_OP_UNSUPPORTED,
 		},
 		[C(OP_PREFETCH)] = {
 			[C(RESULT_ACCESS)]  = CACHE_OP_UNSUPPORTED,
diff --git a/arch/arm/kernel/perf_event_v7.c b/arch/arm/kernel/perf_event_v7.c
index 4fbc757d9cff..8c79a9e70b83 100644
--- a/arch/arm/kernel/perf_event_v7.c
+++ b/arch/arm/kernel/perf_event_v7.c
@@ -157,8 +157,8 @@ static const unsigned armv7_a8_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
 			[C(RESULT_MISS)]	= ARMV7_PERFCTR_L1_ICACHE_REFILL,
 		},
 		[C(OP_WRITE)] = {
-			[C(RESULT_ACCESS)]	= ARMV7_A8_PERFCTR_L1_ICACHE_ACCESS,
-			[C(RESULT_MISS)]	= ARMV7_PERFCTR_L1_ICACHE_REFILL,
+			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
+			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
 		},
 		[C(OP_PREFETCH)] = {
 			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
@@ -282,7 +282,7 @@ static const unsigned armv7_a9_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
 		},
 		[C(OP_WRITE)] = {
 			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
-			[C(RESULT_MISS)]	= ARMV7_PERFCTR_L1_ICACHE_REFILL,
+			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
 		},
 		[C(OP_PREFETCH)] = {
 			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
@@ -399,8 +399,8 @@ static const unsigned armv7_a5_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
 			[C(RESULT_MISS)]	= ARMV7_PERFCTR_L1_ICACHE_REFILL,
 		},
 		[C(OP_WRITE)] = {
-			[C(RESULT_ACCESS)]	= ARMV7_PERFCTR_L1_ICACHE_ACCESS,
-			[C(RESULT_MISS)]	= ARMV7_PERFCTR_L1_ICACHE_REFILL,
+			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
+			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
 		},
 		/*
 		 * The prefetch counters don't differentiate between the I
@@ -527,8 +527,8 @@ static const unsigned armv7_a15_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
 			[C(RESULT_MISS)]	= ARMV7_PERFCTR_L1_ICACHE_REFILL,
 		},
 		[C(OP_WRITE)] = {
-			[C(RESULT_ACCESS)]	= ARMV7_PERFCTR_L1_ICACHE_ACCESS,
-			[C(RESULT_MISS)]	= ARMV7_PERFCTR_L1_ICACHE_REFILL,
+			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
+			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
 		},
 		[C(OP_PREFETCH)] = {
 			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
@@ -651,8 +651,8 @@ static const unsigned armv7_a7_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
 			[C(RESULT_MISS)]	= ARMV7_PERFCTR_L1_ICACHE_REFILL,
 		},
 		[C(OP_WRITE)] = {
-			[C(RESULT_ACCESS)]	= ARMV7_PERFCTR_L1_ICACHE_ACCESS,
-			[C(RESULT_MISS)]	= ARMV7_PERFCTR_L1_ICACHE_REFILL,
+			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
+			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
 		},
 		[C(OP_PREFETCH)] = {
 			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
diff --git a/arch/arm/kernel/perf_event_xscale.c b/arch/arm/kernel/perf_event_xscale.c
index 2b0fe30ec12e..63990c42fac9 100644
--- a/arch/arm/kernel/perf_event_xscale.c
+++ b/arch/arm/kernel/perf_event_xscale.c
@@ -83,7 +83,7 @@ static const unsigned xscale_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
 		},
 		[C(OP_WRITE)] = {
 			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
-			[C(RESULT_MISS)]	= XSCALE_PERFCTR_ICACHE_MISS,
+			[C(RESULT_MISS)]	= CACHE_OP_UNSUPPORTED,
 		},
 		[C(OP_PREFETCH)] = {
 			[C(RESULT_ACCESS)]	= CACHE_OP_UNSUPPORTED,
diff --git a/arch/arm/mach-omap2/omap-smp.c b/arch/arm/mach-omap2/omap-smp.c
index cd42d921940d..e683d0dcef6b 100644
--- a/arch/arm/mach-omap2/omap-smp.c
+++ b/arch/arm/mach-omap2/omap-smp.c
@@ -215,7 +215,7 @@ static void __init omap4_smp_init_cpus(void)
 		 * Currently we can't call ioremap here because
 		 * SoC detection won't work until after init_early.
 		 */
-		scu_base =  OMAP2_L4_IO_ADDRESS(OMAP44XX_SCU_BASE);
+		scu_base =  OMAP2_L4_IO_ADDRESS(scu_a9_get_base());
 		BUG_ON(!scu_base);
 		ncores = scu_get_core_count(scu_base);
 	} else if (cpu_id == CPU_CORTEX_A15) {
diff --git a/arch/arm/mach-omap2/omap44xx.h b/arch/arm/mach-omap2/omap44xx.h
index 43b927b2e2e8..8a515bb74639 100644
--- a/arch/arm/mach-omap2/omap44xx.h
+++ b/arch/arm/mach-omap2/omap44xx.h
@@ -40,7 +40,6 @@
 #define OMAP44XX_GIC_DIST_BASE		0x48241000
 #define OMAP44XX_GIC_CPU_BASE		0x48240100
 #define OMAP44XX_IRQ_GIC_START		32
-#define OMAP44XX_SCU_BASE		0x48240000
 #define OMAP44XX_LOCAL_TWD_BASE		0x48240600
 #define OMAP44XX_L2CACHE_BASE		0x48242000
 #define OMAP44XX_WKUPGEN_BASE		0x48281000
diff --git a/arch/arm/mach-tegra/platsmp.c b/arch/arm/mach-tegra/platsmp.c
index 3ec7fc487857..2ff68a47099d 100644
--- a/arch/arm/mach-tegra/platsmp.c
+++ b/arch/arm/mach-tegra/platsmp.c
@@ -38,7 +38,6 @@
 extern void tegra_secondary_startup(void);
 
 static cpumask_t tegra_cpu_init_mask;
-static void __iomem *scu_base = IO_ADDRESS(TEGRA_ARM_PERIF_BASE);
 
 #define EVP_CPU_RESET_VECTOR \
 	(IO_ADDRESS(TEGRA_EXCEPTION_VECTORS_BASE) + 0x100)
@@ -177,23 +176,8 @@ static int __cpuinit tegra_boot_secondary(unsigned int cpu, struct task_struct *
 	return status;
 }
 
-/*
- * Initialise the CPU possible map early - this describes the CPUs
- * which may be present or become present in the system.
- */
 static void __init tegra_smp_init_cpus(void)
 {
-	unsigned int i, ncores = scu_get_core_count(scu_base);
-
-	if (ncores > nr_cpu_ids) {
-		pr_warn("SMP: %u cores greater than maximum (%u), clipping\n",
-			ncores, nr_cpu_ids);
-		ncores = nr_cpu_ids;
-	}
-
-	for (i = 0; i < ncores; i++)
-		set_cpu_possible(i, true);
-
 	set_smp_cross_call(gic_raise_softirq);
 }
 
@@ -202,7 +186,8 @@ static void __init tegra_smp_prepare_cpus(unsigned int max_cpus)
 	/* Always mark the boot CPU (CPU0) as initialized. */
 	cpumask_set_cpu(0, &tegra_cpu_init_mask);
 
-	scu_enable(scu_base);
+	if (scu_a9_has_base())
+		scu_enable(IO_ADDRESS(scu_a9_get_base()));
 }
 
 struct smp_operations tegra_smp_ops __initdata = {