LXR linux/arch/arm/include/asm/smp

   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 */
  18static 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 */
  36static 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
  48static 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
  60static 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 */
  72extern 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 */
  80static 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 */
  95struct mpidr_hash {
  96        u32     mask; /* used by sleep.S */
  97        u32     shift_aff[3]; /* used by sleep.S */
  98        u32     bits;
  99};
 100
 101extern struct mpidr_hash mpidr_hash;
 102
 103static inline u32 mpidr_hash_size(void)
 104{
 105        return 1 << mpidr_hash.bits;
 106}
 107
 108extern int platform_can_secondary_boot(void);
 109extern int platform_can_cpu_hotplug(void);
 110
 111#ifdef CONFIG_HOTPLUG_CPU
 112extern int platform_can_hotplug_cpu(unsigned int cpu);
 113#else
 114static inline int platform_can_hotplug_cpu(unsigned int cpu)
 115{
 116        return 0;
 117}
 118#endif
 119
 120#endif
 121