ARM_CPU_XSCALE_ARCH_MASK 248 arch/arm/include/asm/cputype.h return read_cpuid_id() & ARM_CPU_XSCALE_ARCH_MASK; ARM_CPU_XSCALE_ARCH_MASK 147 include/linux/perf/arm_pmu.h #define ARM_PMU_XSCALE_MASK ((0xff << 24) | ARM_CPU_XSCALE_ARCH_MASK)