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Diffstat (limited to '')
-rw-r--r-- | comm/third_party/libgcrypt/src/hwf-s390x.c | 230 |
1 files changed, 230 insertions, 0 deletions
diff --git a/comm/third_party/libgcrypt/src/hwf-s390x.c b/comm/third_party/libgcrypt/src/hwf-s390x.c new file mode 100644 index 0000000000..25121b91ce --- /dev/null +++ b/comm/third_party/libgcrypt/src/hwf-s390x.c @@ -0,0 +1,230 @@ +/* hwf-s390x.c - Detect hardware features - s390x/zSeries part + * Copyright (C) 2020 Jussi Kivilinna <jussi.kivilinna@iki.fi> + * + * This file is part of Libgcrypt. + * + * Libgcrypt is free software; you can redistribute it and/or modify + * it under the terms of the GNU Lesser General Public License as + * published by the Free Software Foundation; either version 2.1 of + * the License, or (at your option) any later version. + * + * Libgcrypt is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this program; if not, see <http://www.gnu.org/licenses/>. + */ + +#include <config.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <stdarg.h> +#include <unistd.h> +#include <errno.h> +#if defined(HAVE_SYS_AUXV_H) && (defined(HAVE_GETAUXVAL) || \ + defined(HAVE_ELF_AUX_INFO)) +#include <sys/auxv.h> +#endif + +#include "g10lib.h" +#include "hwf-common.h" + +#if !defined (__s390x__) +# error Module build for wrong CPU. +#endif + +#undef HAVE_STFLE +#ifdef HAVE_GCC_INLINE_ASM_S390X +# define HAVE_STFLE 1 +#endif + +#ifndef AT_HWCAP +# define AT_HWCAP 16 +#endif +#ifndef HWCAP_S390_STFLE +# define HWCAP_S390_STFLE 4 +#endif +#ifndef HWCAP_S390_VXRS +# define HWCAP_S390_VXRS 2048 +#endif + +struct feature_map_s + { + unsigned int facilities_bit; + unsigned int hwcap_flag; + unsigned int hwf_flag; + }; + +static const struct feature_map_s s390x_features[] = + { + { 17, 0, HWF_S390X_MSA }, + { 77, 0, HWF_S390X_MSA_4 }, + { 146, 0, HWF_S390X_MSA_8 }, +#ifdef HAVE_GCC_INLINE_ASM_S390X_VX + { 129, HWCAP_S390_VXRS, HWF_S390X_VX }, +#endif + }; + +#if defined(HAVE_SYS_AUXV_H) && defined(HAVE_ELF_AUX_INFO) && \ + !defined(HAVE_GETAUXVAL) && defined(AT_HWCAP) +#define HAVE_GETAUXVAL +static unsigned long getauxval(unsigned long type) +{ + unsigned long auxval = 0; + int err; + + /* FreeBSD provides 'elf_aux_info' function that does the same as + * 'getauxval' on Linux. */ + + err = elf_aux_info (type, &auxval, sizeof(auxval)); + if (err) + { + errno = err; + auxval = 0; + } + + return auxval; +} +#endif + + +#undef HAS_SYS_AT_HWCAP +#if defined(__linux__) || \ + (defined(HAVE_SYS_AUXV_H) && defined(HAVE_GETAUXVAL)) +#define HAS_SYS_AT_HWCAP 1 + +struct facilities_s + { + u64 bits[3]; + }; + +static int +get_hwcap(unsigned int *hwcap) +{ + struct { unsigned long a_type; unsigned long a_val; } auxv; + FILE *f; + int err = -1; + static int hwcap_initialized = 0; + static unsigned int stored_hwcap = 0; + + if (hwcap_initialized) + { + *hwcap = stored_hwcap; + return 0; + } + +#if defined(HAVE_SYS_AUXV_H) && defined(HAVE_GETAUXVAL) + errno = 0; + auxv.a_val = getauxval (AT_HWCAP); + if (errno == 0) + { + stored_hwcap |= auxv.a_val; + hwcap_initialized = 1; + } + + if (hwcap_initialized && stored_hwcap) + { + *hwcap = stored_hwcap; + return 0; + } +#endif + + f = fopen("/proc/self/auxv", "r"); + if (!f) + { + *hwcap = stored_hwcap; + return -1; + } + + while (fread(&auxv, sizeof(auxv), 1, f) > 0) + { + if (auxv.a_type == AT_HWCAP) + { + stored_hwcap |= auxv.a_val; + hwcap_initialized = 1; + } + } + + if (hwcap_initialized) + err = 0; + + fclose(f); + + *hwcap = stored_hwcap; + return err; +} +#endif + +#ifdef HAVE_STFLE +static void +get_stfle(struct facilities_s *out) +{ + static int stfle_initialized = 0; + static struct facilities_s stored_facilities; + + if (!stfle_initialized) + { + register unsigned long reg0 asm("0") = DIM(stored_facilities.bits) - 1; + + asm ("stfle %1\n\t" + : "+d" (reg0), + "=Q" (stored_facilities.bits[0]) + : + : "cc", "memory"); + + stfle_initialized = 1; + } + + *out = stored_facilities; +} +#endif + +static unsigned int +detect_s390x_features(void) +{ + struct facilities_s facilities = { { 0, } }; + unsigned int hwcap = 0; + unsigned int features = 0; + unsigned int i; + +#if defined (HAS_SYS_AT_HWCAP) + if (get_hwcap(&hwcap) < 0) + return features; +#endif + + if ((hwcap & HWCAP_S390_STFLE) == 0) + return features; + +#ifdef HAVE_STFLE + get_stfle(&facilities); +#endif + + for (i = 0; i < DIM(s390x_features); i++) + { + if (s390x_features[i].hwcap_flag == 0 || + (s390x_features[i].hwcap_flag & hwcap)) + { + unsigned int idx = s390x_features[i].facilities_bit; + unsigned int u64_idx = idx / 64; + unsigned int u64_bit = 63 - (idx % 64); + + if (facilities.bits[u64_idx] & (U64_C(1) << u64_bit)) + features |= s390x_features[i].hwf_flag; + } + } + + return features; +} + +unsigned int +_gcry_hwf_detect_s390x (void) +{ + unsigned int ret = 0; + + ret |= detect_s390x_features (); + + return ret; +} |