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/cpu.h>
  12 #include <asm/cputype.h>
  13
  14 /*
  15  * Return true if we are running on a SMP platform
  16  */
  17 static inline bool is_smp(void)
  18 {
  19 #ifndef CONFIG_SMP
  20         return false;
  21 #elif defined(CONFIG_SMP_ON_UP)
  22         extern unsigned int smp_on_up;
  23         return !!smp_on_up;
  24 #else
  25         return true;
  26 #endif
  27 }
  28
  29 /**
  30  * smp_cpuid_part() - return part id for a given cpu
  31  * @cpu:        logical cpu id.
  32  *
  33  * Return: part id of logical cpu passed as argument.
  34  */
  35 static inline unsigned int smp_cpuid_part(int cpu)
  36 {
  37         struct cpuinfo_arm *cpu_info = &per_cpu(cpu_data, cpu);
  38
  39         return is_smp() ? cpu_info->cpuid & ARM_CPU_PART_MASK :
  40                           read_cpuid_part();
  41 }
  42
  43 /* all SMP configurations have the extended CPUID registers */
  44 #ifndef CONFIG_MMU
  45 #define tlb_ops_need_broadcast()        0
  46 #else
  47 static inline int tlb_ops_need_broadcast(void)
  48 {
  49         if (!is_smp())
  50                 return 0;
  51
  52         return ((read_cpuid_ext(CPUID_EXT_MMFR3) >> 12) & 0xf) < 2;
  53 }
  54 #endif
  55
  56 #if !defined(CONFIG_SMP) || __LINUX_ARM_ARCH__ >= 7
  57 #define cache_ops_need_broadcast()      0
  58 #else
  59 static inline int cache_ops_need_broadcast(void)
  60 {
  61         if (!is_smp())
  62                 return 0;
  63
  64         return ((read_cpuid_ext(CPUID_EXT_MMFR3) >> 12) & 0xf) < 1;
  65 }
  66 #endif
  67
  68 /*
  69  * Logical CPU mapping.
  70  */
  71 extern u32 __cpu_logical_map[];
  72 #define cpu_logical_map(cpu)    __cpu_logical_map[cpu]
  73 /*
  74  * Retrieve logical cpu index corresponding to a given MPIDR[23:0]
  75  *  - mpidr: MPIDR[23:0] to be used for the look-up
  76  *
  77  * Returns the cpu logical index or -EINVAL on look-up error
  78  */
  79 static inline int get_logical_index(u32 mpidr)
  80 {
  81         int cpu;
  82         for (cpu = 0; cpu < nr_cpu_ids; cpu++)
  83                 if (cpu_logical_map(cpu) == mpidr)
  84                         return cpu;
  85         return -EINVAL;
  86 }
  87
  88 /*
  89  * NOTE ! Assembly code relies on the following
  90  * structure memory layout in order to carry out load
  91  * multiple from its base address. For more
  92  * information check arch/arm/kernel/sleep.S
  93  */
  94 struct mpidr_hash {
  95         u32     mask; /* used by sleep.S */
  96         u32     shift_aff[3]; /* used by sleep.S */
  97         u32     bits;
  98 };
  99
 100 extern struct mpidr_hash mpidr_hash;
 101
 102 static inline u32 mpidr_hash_size(void)
 103 {
 104         return 1 << mpidr_hash.bits;
 105 }
 106
 107 extern int platform_can_cpu_hotplug(void);
 108
 109 #endif