c - Detect Power8 runtime environment and in-core crypto through getauxval? -

i'm on gcc112, little-endian power8 machine running linux. power8 has in-core crypto providing aes, sha , few other useful features. i'm trying determine availability of features @ runtime using getauxval. use case distros building "minimum" capable machine, , need swap-in faster function @ runtime.

the dump of hwcaps.h shown below, lacks specific bits power8, aes, sha , others. however, believe power8 isa 2.07, , isa 2.07 has bit ppc_feature2_arch_2_07.

the thing not clear on is, power8 in-core crypto optional arm's crypto under armv8. can't find document states requirement, , don't have membership openpower access isa documents. (another possibility is, stated missed in docs).

is possible use getauxval query runtime environment features? if not, how determine feature availability @ runtime? cpu probing alternative available?

maybe more generally, how determine power6, power7 , power8 runtime environments?

---

auxv.h empty. header file includes hwcaps.h.

$ cat /usr/include/bits/hwcap.h ...  /* bit numbers must match in kernel's asm/cputable.h.  */  /* feature definitions in at_hwcap.  */ #define ppc_feature_32              0x80000000 /* 32-bit mode. */ #define ppc_feature_64              0x40000000 /* 64-bit mode. */ #define ppc_feature_601_instr       0x20000000 /* 601 chip, old power isa.  */ #define ppc_feature_has_altivec     0x10000000 /* simd/vector unit.  */ #define ppc_feature_has_fpu         0x08000000 /* floating point unit.  */ #define ppc_feature_has_mmu         0x04000000 /* memory management unit.  */ #define ppc_feature_has_4xxmac      0x02000000 /* 4xx multiply accumulator.  */ #define ppc_feature_unified_cache   0x01000000 /* unified i/d cache.  */ #define ppc_feature_has_spe         0x00800000 /* signal processing ext.  */ #define ppc_feature_has_efp_single  0x00400000 /* spe float.  */ #define ppc_feature_has_efp_double  0x00200000 /* spe double.  */ #define ppc_feature_no_tb           0x00100000 /* 601/403gx have no timebase */ #define ppc_feature_power4          0x00080000 /* power4 isa 2.00 */ #define ppc_feature_power5          0x00040000 /* power5 isa 2.02 */ #define ppc_feature_power5_plus     0x00020000 /* power5+ isa 2.03 */ #define ppc_feature_cell_be         0x00010000 /* cell broadband engine */ #define ppc_feature_booke           0x00008000 /* isa category embedded */ #define ppc_feature_smt             0x00004000 /* simultaneous                                                   multi-threading */ #define ppc_feature_icache_snoop    0x00002000 #define ppc_feature_arch_2_05       0x00001000 /* isa 2.05 */ #define ppc_feature_pa6t            0x00000800 /* pa semi 6t core */ #define ppc_feature_has_dfp         0x00000400 /* decimal fp unit */ #define ppc_feature_power6_ext      0x00000200 /* p6 + mffgpr/mftgpr */ #define ppc_feature_arch_2_06       0x00000100 /* isa 2.06 */ #define ppc_feature_has_vsx         0x00000080 /* p7 vector extension.  */ #define ppc_feature_pseries_perfmon_compat  0x00000040 #define ppc_feature_true_le         0x00000002 #define ppc_feature_ppc_le          0x00000001  /* feature definitions in at_hwcap2.  */ #define ppc_feature2_arch_2_07     0x80000000 /* isa 2.07 */ #define ppc_feature2_has_htm       0x40000000 /* hardware transactional                                                  memory */ #define ppc_feature2_has_dscr      0x20000000 /* data stream control                                                  register */ #define ppc_feature2_has_ebb       0x10000000 /* event base branching */ #define ppc_feature2_has_isel      0x08000000 /* integer select */ #define ppc_feature2_has_tar       0x04000000 /* target address register */ 

i'd getauxval() best way this; hwcap & hwcap2 values determining hardware features. missing list ppc_feature2_vec_crypto, indicates presence of vector crypto instructions, sounds 1 need.

as side note: don't want detect processor implementations, processor features. specifically, check individual feature, rather trying check process provides feature. (eg., detect vec_crypto directly, rather trying check power8, , assume that implies crypto functionality).

as bit of detail, linux's cputable entries specify hwcap/hwcap2 values. using power8 example:

#define common_user2_power8 (ppc_feature2_arch_2_07 | \                  ppc_feature2_htm_comp | \                  ppc_feature2_htm_nosc_comp | \                  ppc_feature2_dscr | \                  ppc_feature2_isel | ppc_feature2_tar | \                  ppc_feature2_vec_crypto) 

that's arch/powerpc/include/asm/cputable.h in kernel (which provides actual hwcap bits can set in aux vector).

finally, i'm sure don't need openpower foundation member download isa (latest 3.0b) - need account on website.