xref: /freebsd/contrib/llvm-project/compiler-rt/lib/builtins/cpu_model/aarch64/fmv/baremetal.inc (revision 700637cbb5e582861067a11aaca4d053546871d2) 
1// For baremetal platforms, we don't really initialise '__aarch64_cpu_features',
2// with exception of FEAT_SME that we can get from '__aarch64_sme_accessible'.
3
4#if defined(COMPILER_RT_SHARED_LIB)
5__attribute__((weak))
6#endif
7extern _Bool
8__aarch64_sme_accessible(void);
9
10static _Bool has_sme(void) {
11#if defined(COMPILER_RT_SHARED_LIB)
12  if (!__aarch64_sme_accessible)
13    return 0;
14#endif
15  return __aarch64_sme_accessible();
16}
17
18void __init_cpu_features_resolver(unsigned long hwcap,
19                                  const __ifunc_arg_t *arg) {}
20
21void CONSTRUCTOR_ATTRIBUTE __init_cpu_features(void) {
22  // CPU features already initialized.
23  if (__atomic_load_n(&__aarch64_cpu_features.features, __ATOMIC_RELAXED))
24    return;
25
26  unsigned long long feat = 0;
27  if (has_sme())
28    feat |= 1ULL << FEAT_SME;
29
30  __atomic_store_n(&__aarch64_cpu_features.features, feat, __ATOMIC_RELAXED);
31}
32