include/asm/smp_plat.h

0001 /* SPDX-License-Identifier: GPL-2.0 */
0002 /*
0003  * ARM specific SMP header, this contains our implementation
0004  * details.
0005  */
0006 #ifndef __ASMARM_SMP_PLAT_H
0007 #define __ASMARM_SMP_PLAT_H
0008
0009 #include <linux/cpumask.h>
0010 #include <linux/err.h>
0011
0012 #include <asm/cpu.h>
0013 #include <asm/cputype.h>
0014
0015 /*
0016  * Return true if we are running on a SMP platform
0017  */
0018 static inline bool is_smp(void)
0019 {
0020 #ifndef CONFIG_SMP
0021     return false;
0022 #elif defined(CONFIG_SMP_ON_UP)
0023     extern unsigned int smp_on_up;
0024     return !!smp_on_up;
0025 #else
0026     return true;
0027 #endif
0028 }
0029
0030 /**
0031  * smp_cpuid_part() - return part id for a given cpu
0032  * @cpu:    logical cpu id.
0033  *
0034  * Return: part id of logical cpu passed as argument.
0035  */
0036 static inline unsigned int smp_cpuid_part(int cpu)
0037 {
0038     struct cpuinfo_arm *cpu_info = &per_cpu(cpu_data, cpu);
0039
0040     return is_smp() ? cpu_info->cpuid & ARM_CPU_PART_MASK :
0041               read_cpuid_part();
0042 }
0043
0044 /* all SMP configurations have the extended CPUID registers */
0045 #ifndef CONFIG_MMU
0046 #define tlb_ops_need_broadcast()    0
0047 #else
0048 static inline int tlb_ops_need_broadcast(void)
0049 {
0050     if (!is_smp())
0051         return 0;
0052
0053     return ((read_cpuid_ext(CPUID_EXT_MMFR3) >> 12) & 0xf) < 2;
0054 }
0055 #endif
0056
0057 #if !defined(CONFIG_SMP) || __LINUX_ARM_ARCH__ >= 7
0058 #define cache_ops_need_broadcast()  0
0059 #else
0060 static inline int cache_ops_need_broadcast(void)
0061 {
0062     if (!is_smp())
0063         return 0;
0064
0065     return ((read_cpuid_ext(CPUID_EXT_MMFR3) >> 12) & 0xf) < 1;
0066 }
0067 #endif
0068
0069 /*
0070  * Logical CPU mapping.
0071  */
0072 extern u32 __cpu_logical_map[];
0073 #define cpu_logical_map(cpu)    __cpu_logical_map[cpu]
0074 /*
0075  * Retrieve logical cpu index corresponding to a given MPIDR[23:0]
0076  *  - mpidr: MPIDR[23:0] to be used for the look-up
0077  *
0078  * Returns the cpu logical index or -EINVAL on look-up error
0079  */
0080 static inline int get_logical_index(u32 mpidr)
0081 {
0082     int cpu;
0083     for (cpu = 0; cpu < nr_cpu_ids; cpu++)
0084         if (cpu_logical_map(cpu) == mpidr)
0085             return cpu;
0086     return -EINVAL;
0087 }
0088
0089 /*
0090  * NOTE ! Assembly code relies on the following
0091  * structure memory layout in order to carry out load
0092  * multiple from its base address. For more
0093  * information check arch/arm/kernel/sleep.S
0094  */
0095 struct mpidr_hash {
0096     u32 mask; /* used by sleep.S */
0097     u32 shift_aff[3]; /* used by sleep.S */
0098     u32 bits;
0099 };
0100
0101 extern struct mpidr_hash mpidr_hash;
0102
0103 static inline u32 mpidr_hash_size(void)
0104 {
0105     return 1 << mpidr_hash.bits;
0106 }
0107
0108 extern int platform_can_secondary_boot(void);
0109 extern int platform_can_cpu_hotplug(void);
0110
0111 #ifdef CONFIG_HOTPLUG_CPU
0112 extern int platform_can_hotplug_cpu(unsigned int cpu);
0113 #else
0114 static inline int platform_can_hotplug_cpu(unsigned int cpu)
0115 {
0116     return 0;
0117 }
0118 #endif
0119
0120 #endif