| 1 | /* |
| 2 | * Helper for pauth test case |
| 3 | * |
| 4 | * Copyright (c) 2023 Linaro Ltd |
| 5 | * SPDX-License-Identifier: GPL-2.0-or-later |
| 6 | */ |
| 7 | |
| 8 | #include <assert.h> |
| 9 | #include <sys/auxv.h> |
| 10 | |
| 11 | static int get_pac_feature(void) |
| 12 | { |
| 13 | unsigned long isar1, isar2; |
| 14 | |
| 15 | assert(getauxval(AT_HWCAP) & HWCAP_CPUID); |
| 16 | |
| 17 | asm("mrs %0, id_aa64isar1_el1" : "=r"(isar1)); |
| 18 | asm("mrs %0, S3_0_C0_C6_2" : "=r"(isar2)); /* id_aa64isar2_el1 */ |
| 19 | |
| 20 | return ((isar1 >> 4) & 0xf) /* APA */ |
| 21 | | ((isar1 >> 8) & 0xf) /* API */ |
| 22 | | ((isar2 >> 12) & 0xf); /* APA3 */ |
| 23 | } |