| xf.li | bdd93d5 | 2023-05-12 07:10:14 -0700 | [diff] [blame^] | 1 | /* powerpc HWCAP/HWCAP2 and AT_PLATFORM data pre-processing. |
| 2 | Copyright (C) 2015-2016 Free Software Foundation, Inc. |
| 3 | This file is part of the GNU C Library. |
| 4 | |
| 5 | The GNU C Library is free software; you can redistribute it and/or |
| 6 | modify it under the terms of the GNU Lesser General Public |
| 7 | License as published by the Free Software Foundation; either |
| 8 | version 2.1 of the License, or (at your option) any later version. |
| 9 | |
| 10 | The GNU C Library is distributed in the hope that it will be useful, |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 13 | Lesser General Public License for more details. |
| 14 | |
| 15 | You should have received a copy of the GNU Lesser General Public |
| 16 | License along with the GNU C Library; if not, see |
| 17 | <http://www.gnu.org/licenses/>. */ |
| 18 | |
| 19 | #include <unistd.h> |
| 20 | #include <shlib-compat.h> |
| 21 | #include <dl-procinfo.h> |
| 22 | |
| 23 | uint64_t __tcb_hwcap __attribute__ ((visibility ("hidden"))); |
| 24 | uint32_t __tcb_platform __attribute__ ((visibility ("hidden"))); |
| 25 | |
| 26 | /* This function parses the HWCAP/HWCAP2 fields, adding the previous supported |
| 27 | ISA bits, as well as converting the AT_PLATFORM string to a number. This |
| 28 | data is stored in two global variables that can be used later by the |
| 29 | powerpc-specific code to store it into the TCB. */ |
| 30 | void |
| 31 | __tcb_parse_hwcap_and_convert_at_platform (void) |
| 32 | { |
| 33 | |
| 34 | uint64_t h1, h2; |
| 35 | |
| 36 | /* Read AT_PLATFORM string from auxv and convert it to a number. */ |
| 37 | __tcb_platform = _dl_string_platform (GLRO (dl_platform)); |
| 38 | |
| 39 | /* Read HWCAP and HWCAP2 from auxv. */ |
| 40 | h1 = GLRO (dl_hwcap); |
| 41 | h2 = GLRO (dl_hwcap2); |
| 42 | |
| 43 | /* hwcap contains only the latest supported ISA, the code checks which is |
| 44 | and fills the previous supported ones. */ |
| 45 | |
| 46 | if (h2 & PPC_FEATURE2_ARCH_2_07) |
| 47 | h1 |= PPC_FEATURE_ARCH_2_06 |
| 48 | | PPC_FEATURE_ARCH_2_05 |
| 49 | | PPC_FEATURE_POWER5_PLUS |
| 50 | | PPC_FEATURE_POWER5 |
| 51 | | PPC_FEATURE_POWER4; |
| 52 | else if (h1 & PPC_FEATURE_ARCH_2_06) |
| 53 | h1 |= PPC_FEATURE_ARCH_2_05 |
| 54 | | PPC_FEATURE_POWER5_PLUS |
| 55 | | PPC_FEATURE_POWER5 |
| 56 | | PPC_FEATURE_POWER4; |
| 57 | else if (h1 & PPC_FEATURE_ARCH_2_05) |
| 58 | h1 |= PPC_FEATURE_POWER5_PLUS |
| 59 | | PPC_FEATURE_POWER5 |
| 60 | | PPC_FEATURE_POWER4; |
| 61 | else if (h1 & PPC_FEATURE_POWER5_PLUS) |
| 62 | h1 |= PPC_FEATURE_POWER5 |
| 63 | | PPC_FEATURE_POWER4; |
| 64 | else if (h1 & PPC_FEATURE_POWER5) |
| 65 | h1 |= PPC_FEATURE_POWER4; |
| 66 | |
| 67 | /* Consolidate both HWCAP and HWCAP2 into a single doubleword so that |
| 68 | we can read both in a single load later. */ |
| 69 | __tcb_hwcap = h2; |
| 70 | __tcb_hwcap = (h1 << 32) | __tcb_hwcap; |
| 71 | |
| 72 | } |
| 73 | #if IS_IN (rtld) |
| 74 | versioned_symbol (ld, __tcb_parse_hwcap_and_convert_at_platform, \ |
| 75 | __parse_hwcap_and_convert_at_platform, GLIBC_2_23); |
| 76 | #endif |
| 77 | |
| 78 | /* Export __parse_hwcap_and_convert_at_platform in libc.a. This is used by |
| 79 | GCC to make sure that the HWCAP/Platform bits are stored in the TCB when |
| 80 | using __builtin_cpu_is()/__builtin_cpu_supports() in the static case. */ |
| 81 | #ifndef SHARED |
| 82 | weak_alias (__tcb_parse_hwcap_and_convert_at_platform, \ |
| 83 | __parse_hwcap_and_convert_at_platform); |
| 84 | #endif |