arch/arm/include/asm/smp_plat.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * ARM specific SMP header, this contains our implementation
   4  * details.
   5  */
   6 #ifndef __ASMARM_SMP_PLAT_H
   7 #define __ASMARM_SMP_PLAT_H
   8
   9 #include <linux/cpumask.h>
  10 #include <linux/err.h>
  11
  12 #include <asm/cpu.h>
  13 #include <asm/cputype.h>
  14
  15 /*
  16  * Return true if we are running on a SMP platform
  17  */
  18 static inline bool is_smp(void)
  19 {
  20 #ifndef CONFIG_SMP
  21         return false;
  22 #elif defined(CONFIG_SMP_ON_UP)
  23         extern unsigned int smp_on_up;
  24         return !!smp_on_up;
  25 #else
  26         return true;
  27 #endif
  28 }
  29
  30 /**
  31  * smp_cpuid_part() - return part id for a given cpu
  32  * @cpu:        logical cpu id.
  33  *
  34  * Return: part id of logical cpu passed as argument.
  35  */
  36 static inline unsigned int smp_cpuid_part(int cpu)
  37 {
  38         struct cpuinfo_arm *cpu_info = &per_cpu(cpu_data, cpu);
  39
  40         return is_smp() ? cpu_info->cpuid & ARM_CPU_PART_MASK :
  41                           read_cpuid_part();
  42 }
  43
  44 /* all SMP configurations have the extended CPUID registers */
  45 #ifndef CONFIG_MMU
  46 #define tlb_ops_need_broadcast()        0
  47 #else
  48 static inline int tlb_ops_need_broadcast(void)
  49 {
  50         if (!is_smp())
  51                 return 0;
  52
  53         return ((read_cpuid_ext(CPUID_EXT_MMFR3) >> 12) & 0xf) < 2;
  54 }
  55 #endif
  56
  57 #if !defined(CONFIG_SMP) || __LINUX_ARM_ARCH__ >= 7
  58 #define cache_ops_need_broadcast()      0
  59 #else
  60 static inline int cache_ops_need_broadcast(void)
  61 {
  62         if (!is_smp())
  63                 return 0;
  64
  65         return ((read_cpuid_ext(CPUID_EXT_MMFR3) >> 12) & 0xf) < 1;
  66 }
  67 #endif
  68
  69 /*
  70  * Logical CPU mapping.
  71  */
  72 extern u32 __cpu_logical_map[];
  73 #define cpu_logical_map(cpu)    __cpu_logical_map[cpu]
  74 /*
  75  * Retrieve logical cpu index corresponding to a given MPIDR[23:0]
  76  *  - mpidr: MPIDR[23:0] to be used for the look-up
  77  *
  78  * Returns the cpu logical index or -EINVAL on look-up error
  79  */
  80 static inline int get_logical_index(u32 mpidr)
  81 {
  82         int cpu;
  83         for (cpu = 0; cpu < nr_cpu_ids; cpu++)
  84                 if (cpu_logical_map(cpu) == mpidr)
  85                         return cpu;
  86         return -EINVAL;
  87 }
  88
  89 /*
  90  * NOTE ! Assembly code relies on the following
  91  * structure memory layout in order to carry out load
  92  * multiple from its base address. For more
  93  * information check arch/arm/kernel/sleep.S
  94  */
  95 struct mpidr_hash {
  96         u32     mask; /* used by sleep.S */
  97         u32     shift_aff[3]; /* used by sleep.S */
  98         u32     bits;
  99 };
 100
 101 extern struct mpidr_hash mpidr_hash;
 102
 103 static inline u32 mpidr_hash_size(void)
 104 {
 105         return 1 << mpidr_hash.bits;
 106 }
 107
 108 extern int platform_can_secondary_boot(void);
 109 extern int platform_can_cpu_hotplug(void);
 110
 111 #ifdef CONFIG_HOTPLUG_CPU
 112 extern int platform_can_hotplug_cpu(unsigned int cpu);
 113 #else
 114 static inline int platform_can_hotplug_cpu(unsigned int cpu)
 115 {
 116         return 0;
 117 }
 118 #endif
 119
 120 #endif