arch/arm/include/asm/smp_plat.h

   1 /*
   2  * ARM specific SMP header, this contains our implementation
   3  * details.
   4  */
   5 #ifndef __ASMARM_SMP_PLAT_H
   6 #define __ASMARM_SMP_PLAT_H
   7
   8 #include <linux/cpumask.h>
   9 #include <linux/err.h>
  10
  11 #include <asm/cputype.h>
  12
  13 /*
  14  * Return true if we are running on a SMP platform
  15  */
  16 static inline bool is_smp(void)
  17 {
  18 #ifndef CONFIG_SMP
  19         return false;
  20 #elif defined(CONFIG_SMP_ON_UP)
  21         extern unsigned int smp_on_up;
  22         return !!smp_on_up;
  23 #else
  24         return true;
  25 #endif
  26 }
  27
  28 /* all SMP configurations have the extended CPUID registers */
  29 #ifndef CONFIG_MMU
  30 #define tlb_ops_need_broadcast()        0
  31 #else
  32 static inline int tlb_ops_need_broadcast(void)
  33 {
  34         if (!is_smp())
  35                 return 0;
  36
  37         return ((read_cpuid_ext(CPUID_EXT_MMFR3) >> 12) & 0xf) < 2;
  38 }
  39 #endif
  40
  41 #if !defined(CONFIG_SMP) || __LINUX_ARM_ARCH__ >= 7
  42 #define cache_ops_need_broadcast()      0
  43 #else
  44 static inline int cache_ops_need_broadcast(void)
  45 {
  46         if (!is_smp())
  47                 return 0;
  48
  49         return ((read_cpuid_ext(CPUID_EXT_MMFR3) >> 12) & 0xf) < 1;
  50 }
  51 #endif
  52
  53 /*
  54  * Logical CPU mapping.
  55  */
  56 extern int __cpu_logical_map[];
  57 #define cpu_logical_map(cpu)    __cpu_logical_map[cpu]
  58 /*
  59  * Retrieve logical cpu index corresponding to a given MPIDR[23:0]
  60  *  - mpidr: MPIDR[23:0] to be used for the look-up
  61  *
  62  * Returns the cpu logical index or -EINVAL on look-up error
  63  */
  64 static inline int get_logical_index(u32 mpidr)
  65 {
  66         int cpu;
  67         for (cpu = 0; cpu < nr_cpu_ids; cpu++)
  68                 if (cpu_logical_map(cpu) == mpidr)
  69                         return cpu;
  70         return -EINVAL;
  71 }
  72
  73 #endif