arm: perf: factor out xscale pmu driver

Now that the core arm perf code maintains no global state and all
microarchitecture-specific PMU data can be fed in through the shared
probe function, it's possible to use it as a library and get rid of the
C file includes we have currently.

This patch factors out the xscale-specific portions out into the xscale
driver. For the moment this is always built if perf event support is
enabled, but the preprocessor guards will leave behind an empty file.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

arch/arm/kernel/Makefile

@@ -70,7 +70,7 @@ obj-$(CONFIG_CPU_PJ4)		+= pj4-cp0.o
 obj-$(CONFIG_CPU_PJ4B)		+= pj4-cp0.o
 obj-$(CONFIG_IWMMXT)		+= iwmmxt.o
 obj-$(CONFIG_PERF_EVENTS)	+= perf_regs.o perf_callchain.o
-obj-$(CONFIG_HW_PERF_EVENTS)	+= perf_event.o perf_event_cpu.o
+obj-$(CONFIG_HW_PERF_EVENTS)	+= perf_event.o perf_event_cpu.o perf_event_xscale.o
 CFLAGS_pj4-cp0.o		:= -marm
 AFLAGS_iwmmxt.o			:= -Wa,-mcpu=iwmmxt
 obj-$(CONFIG_ARM_CPU_TOPOLOGY)  += topology.o

arch/arm/kernel/perf_event_cpu.c

@@ -60,7 +60,6 @@ int perf_num_counters(void)
 EXPORT_SYMBOL_GPL(perf_num_counters);
 
 /* Include the PMU-specific implementations. */
-#include "perf_event_xscale.c"
 #include "perf_event_v6.c"
 #include "perf_event_v7.c"
 
@@ -267,7 +266,6 @@ static struct platform_device_id cpu_pmu_plat_device_ids[] = {
 	{.name = "arm-pmu"},
 	{.name = "armv6-pmu"},
 	{.name = "armv7-pmu"},
-	{.name = "xscale-pmu"},
 	{},
 };
 
@@ -278,8 +276,6 @@ static const struct pmu_probe_info pmu_probe_table[] = {
 	ARM_PMU_PROBE(ARM_CPU_PART_ARM11MPCORE, armv6mpcore_pmu_init),
 	ARM_PMU_PROBE(ARM_CPU_PART_CORTEX_A8, armv7_a8_pmu_init),
 	ARM_PMU_PROBE(ARM_CPU_PART_CORTEX_A9, armv7_a9_pmu_init),
-	XSCALE_PMU_PROBE(ARM_CPU_XSCALE_ARCH_V1, xscale1pmu_init),
-	XSCALE_PMU_PROBE(ARM_CPU_XSCALE_ARCH_V2, xscale2pmu_init),
 	{ /* sentinel value */ }
 };
 

arch/arm/kernel/perf_event_xscale.c

@@ -13,6 +13,14 @@
  */
 
 #ifdef CONFIG_CPU_XSCALE
+
+#include <asm/cputype.h>
+#include <asm/irq_regs.h>
+#include <asm/pmu.h>
+
+#include <linux/of.h>
+#include <linux/platform_device.h>
+
 enum xscale_perf_types {
 	XSCALE_PERFCTR_ICACHE_MISS		= 0x00,
 	XSCALE_PERFCTR_ICACHE_NO_DELIVER	= 0x01,
@@ -740,14 +748,28 @@ static int xscale2pmu_init(struct arm_pmu *cpu_pmu)
 
 	return 0;
 }
-#else
-static inline int xscale1pmu_init(struct arm_pmu *cpu_pmu)
+
+static const struct pmu_probe_info xscale_pmu_probe_table[] = {
+	XSCALE_PMU_PROBE(ARM_CPU_XSCALE_ARCH_V1, xscale1pmu_init),
+	XSCALE_PMU_PROBE(ARM_CPU_XSCALE_ARCH_V2, xscale2pmu_init),
+	{ /* sentinel value */ }
+};
+
+static int xscale_pmu_device_probe(struct platform_device *pdev)
 {
-	return -ENODEV;
+	return arm_pmu_device_probe(pdev, NULL, xscale_pmu_probe_table);
 }
 
-static inline int xscale2pmu_init(struct arm_pmu *cpu_pmu)
+static struct platform_driver xscale_pmu_driver = {
+	.driver		= {
+		.name	= "xscale-pmu",
+	},
+	.probe		= xscale_pmu_device_probe,
+};
+
+static int __init register_xscale_pmu_driver(void)
 {
-	return -ENODEV;
+	return platform_driver_register(&xscale_pmu_driver);
 }
+device_initcall(register_xscale_pmu_driver);
 #endif	/* CONFIG_CPU_XSCALE */