diff options
Diffstat (limited to 'current/sources/android/cpufeatures/cpu-features.c')
| -rw-r--r-- | current/sources/android/cpufeatures/cpu-features.c | 80 |
1 files changed, 76 insertions, 4 deletions
diff --git a/current/sources/android/cpufeatures/cpu-features.c b/current/sources/android/cpufeatures/cpu-features.c index 7569d3e5d..6dae30c21 100644 --- a/current/sources/android/cpufeatures/cpu-features.c +++ b/current/sources/android/cpufeatures/cpu-features.c @@ -70,7 +70,6 @@ #include <stdio.h> #include <stdlib.h> #include <string.h> -#include <sys/auxv.h> #include <sys/system_properties.h> #include <unistd.h> @@ -492,6 +491,56 @@ cpulist_read_from(CpuList* list, const char* filename) HWCAP_IDIVT ) #endif +#if defined(__mips__) +// see <uapi/asm/hwcap.h> kernel header +#define HWCAP_MIPS_R6 (1 << 0) +#define HWCAP_MIPS_MSA (1 << 1) +#endif + +#if defined(__arm__) || defined(__aarch64__) || defined(__mips__) + +#define AT_HWCAP 16 +#define AT_HWCAP2 26 + +// Probe the system's C library for a 'getauxval' function and call it if +// it exits, or return 0 for failure. This function is available since API +// level 20. +// +// This code does *NOT* check for '__ANDROID_API__ >= 20' to support the +// edge case where some NDK developers use headers for a platform that is +// newer than the one really targetted by their application. +// This is typically done to use newer native APIs only when running on more +// recent Android versions, and requires careful symbol management. +// +// Note that getauxval() can't really be re-implemented here, because +// its implementation does not parse /proc/self/auxv. Instead it depends +// on values that are passed by the kernel at process-init time to the +// C runtime initialization layer. +static uint32_t +get_elf_hwcap_from_getauxval(int hwcap_type) { + typedef unsigned long getauxval_func_t(unsigned long); + + dlerror(); + void* libc_handle = dlopen("libc.so", RTLD_NOW); + if (!libc_handle) { + D("Could not dlopen() C library: %s\n", dlerror()); + return 0; + } + + uint32_t ret = 0; + getauxval_func_t* func = (getauxval_func_t*) + dlsym(libc_handle, "getauxval"); + if (!func) { + D("Could not find getauxval() in C library\n"); + } else { + // Note: getauxval() returns 0 on failure. Doesn't touch errno. + ret = (uint32_t)(*func)(hwcap_type); + } + dlclose(libc_handle); + return ret; +} +#endif + #if defined(__arm__) // Parse /proc/self/auxv to extract the ELF HW capabilities bitmap for the // current CPU. Note that this file is not accessible from regular @@ -610,6 +659,11 @@ android_cpuInitFamily(void) g_cpuFamily = ANDROID_CPU_FAMILY_ARM; #elif defined(__i386__) g_cpuFamily = ANDROID_CPU_FAMILY_X86; +#elif defined(__mips64) +/* Needs to be before __mips__ since the compiler defines both */ + g_cpuFamily = ANDROID_CPU_FAMILY_MIPS64; +#elif defined(__mips__) + g_cpuFamily = ANDROID_CPU_FAMILY_MIPS; #elif defined(__aarch64__) g_cpuFamily = ANDROID_CPU_FAMILY_ARM64; #elif defined(__x86_64__) @@ -721,7 +775,8 @@ android_cpuInit(void) } /* Extract the list of CPU features from ELF hwcaps */ - uint32_t hwcaps = getauxval(AT_HWCAP); + uint32_t hwcaps = 0; + hwcaps = get_elf_hwcap_from_getauxval(AT_HWCAP); if (!hwcaps) { D("Parsing /proc/self/auxv to extract ELF hwcaps!\n"); hwcaps = get_elf_hwcap_from_proc_self_auxv(); @@ -794,7 +849,8 @@ android_cpuInit(void) } /* Extract the list of CPU features from ELF hwcaps2 */ - uint32_t hwcaps2 = getauxval(AT_HWCAP2); + uint32_t hwcaps2 = 0; + hwcaps2 = get_elf_hwcap_from_getauxval(AT_HWCAP2); if (hwcaps2 != 0) { int has_aes = (hwcaps2 & HWCAP2_AES); int has_pmull = (hwcaps2 & HWCAP2_PMULL); @@ -903,7 +959,8 @@ android_cpuInit(void) #ifdef __aarch64__ { /* Extract the list of CPU features from ELF hwcaps */ - uint32_t hwcaps = getauxval(AT_HWCAP); + uint32_t hwcaps = 0; + hwcaps = get_elf_hwcap_from_getauxval(AT_HWCAP); if (hwcaps != 0) { int has_fp = (hwcaps & HWCAP_FP); int has_asimd = (hwcaps & HWCAP_ASIMD); @@ -987,6 +1044,21 @@ android_cpuInit(void) #endif +#if defined( __mips__) + { /* MIPS and MIPS64 */ + /* Extract the list of CPU features from ELF hwcaps */ + uint32_t hwcaps = 0; + hwcaps = get_elf_hwcap_from_getauxval(AT_HWCAP); + if (hwcaps != 0) { + int has_r6 = (hwcaps & HWCAP_MIPS_R6); + int has_msa = (hwcaps & HWCAP_MIPS_MSA); + if (has_r6) + g_cpuFeatures |= ANDROID_CPU_MIPS_FEATURE_R6; + if (has_msa) + g_cpuFeatures |= ANDROID_CPU_MIPS_FEATURE_MSA; + } + } +#endif /* __mips__ */ free(cpuinfo); } |