arch/powerpc/include/asm/cputhreads.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _ASM_POWERPC_CPUTHREADS_H
   3 #define _ASM_POWERPC_CPUTHREADS_H
   4
   5 #ifndef __ASSEMBLY__
   6 #include <linux/cpumask.h>
   7 #include <asm/cpu_has_feature.h>
   8
   9 /*
  10  * Mapping of threads to cores
  11  *
  12  * Note: This implementation is limited to a power of 2 number of
  13  * threads per core and the same number for each core in the system
  14  * (though it would work if some processors had less threads as long
  15  * as the CPU numbers are still allocated, just not brought online).
  16  *
  17  * However, the API allows for a different implementation in the future
  18  * if needed, as long as you only use the functions and not the variables
  19  * directly.
  20  */
  21
  22 #ifdef CONFIG_SMP
  23 extern int threads_per_core;
  24 extern int threads_per_subcore;
  25 extern int threads_shift;
  26 extern cpumask_t threads_core_mask;
  27 #else
  28 #define threads_per_core        1
  29 #define threads_per_subcore     1
  30 #define threads_shift           0
  31 #define threads_core_mask       (*get_cpu_mask(0))
  32 #endif
  33
  34 /* cpu_thread_mask_to_cores - Return a cpumask of one per cores
  35  *                            hit by the argument
  36  *
  37  * @threads:    a cpumask of online threads
  38  *
  39  * This function returns a cpumask which will have one online cpu's
  40  * bit set for each core that has at least one thread set in the argument.
  41  *
  42  * This can typically be used for things like IPI for tlb invalidations
  43  * since those need to be done only once per core/TLB
  44  */
  45 static inline cpumask_t cpu_thread_mask_to_cores(const struct cpumask *threads)
  46 {
  47         cpumask_t       tmp, res;
  48         int             i, cpu;
  49
  50         cpumask_clear(&res);
  51         for (i = 0; i < NR_CPUS; i += threads_per_core) {
  52                 cpumask_shift_left(&tmp, &threads_core_mask, i);
  53                 if (cpumask_intersects(threads, &tmp)) {
  54                         cpu = cpumask_next_and(-1, &tmp, cpu_online_mask);
  55                         if (cpu < nr_cpu_ids)
  56                                 cpumask_set_cpu(cpu, &res);
  57                 }
  58         }
  59         return res;
  60 }
  61
  62 static inline int cpu_nr_cores(void)
  63 {
  64         return nr_cpu_ids >> threads_shift;
  65 }
  66
  67 static inline cpumask_t cpu_online_cores_map(void)
  68 {
  69         return cpu_thread_mask_to_cores(cpu_online_mask);
  70 }
  71
  72 #ifdef CONFIG_SMP
  73 int cpu_core_index_of_thread(int cpu);
  74 int cpu_first_thread_of_core(int core);
  75 #else
  76 static inline int cpu_core_index_of_thread(int cpu) { return cpu; }
  77 static inline int cpu_first_thread_of_core(int core) { return core; }
  78 #endif
  79
  80 static inline int cpu_thread_in_core(int cpu)
  81 {
  82         return cpu & (threads_per_core - 1);
  83 }
  84
  85 static inline int cpu_thread_in_subcore(int cpu)
  86 {
  87         return cpu & (threads_per_subcore - 1);
  88 }
  89
  90 static inline int cpu_first_thread_sibling(int cpu)
  91 {
  92         return cpu & ~(threads_per_core - 1);
  93 }
  94
  95 static inline int cpu_last_thread_sibling(int cpu)
  96 {
  97         return cpu | (threads_per_core - 1);
  98 }
  99
 100 static inline u32 get_tensr(void)
 101 {
 102 #ifdef  CONFIG_BOOKE
 103         if (cpu_has_feature(CPU_FTR_SMT))
 104                 return mfspr(SPRN_TENSR);
 105 #endif
 106         return 1;
 107 }
 108
 109 void book3e_start_thread(int thread, unsigned long addr);
 110 void book3e_stop_thread(int thread);
 111
 112 #endif /* __ASSEMBLY__ */
 113
 114 #define INVALID_THREAD_HWID     0x0fff
 115
 116 #endif /* _ASM_POWERPC_CPUTHREADS_H */
 117