diff options
Diffstat (limited to 'lib/cpus/aarch64/cpu_helpers.S')
| -rw-r--r-- | lib/cpus/aarch64/cpu_helpers.S | 37 |
1 files changed, 34 insertions, 3 deletions
diff --git a/lib/cpus/aarch64/cpu_helpers.S b/lib/cpus/aarch64/cpu_helpers.S index ae1c3c25..5a9226d8 100644 --- a/lib/cpus/aarch64/cpu_helpers.S +++ b/lib/cpus/aarch64/cpu_helpers.S @@ -1,5 +1,5 @@ /* - * Copyright (c) 2014-2017, ARM Limited and Contributors. All rights reserved. + * Copyright (c) 2014-2018, ARM Limited and Contributors. All rights reserved. * * SPDX-License-Identifier: BSD-3-Clause */ @@ -7,9 +7,7 @@ #include <arch.h> #include <asm_macros.S> #include <assert_macros.S> -#if defined(IMAGE_BL31) || (defined(IMAGE_BL2) && BL2_AT_EL3) #include <cpu_data.h> -#endif #include <cpu_macros.S> #include <debug.h> #include <errata_report.h> @@ -281,3 +279,36 @@ func print_errata_status br x1 endfunc print_errata_status #endif + +/* + * int check_workaround_cve_2017_5715(void); + * + * This function returns: + * - ERRATA_APPLIES when firmware mitigation is required. + * - ERRATA_NOT_APPLIES when firmware mitigation is _not_ required. + * - ERRATA_MISSING when firmware mitigation would be required but + * is not compiled in. + * + * NOTE: Must be called only after cpu_ops have been initialized + * in per-CPU data. + */ + .globl check_workaround_cve_2017_5715 +func check_workaround_cve_2017_5715 + mrs x0, tpidr_el3 +#if ENABLE_ASSERTIONS + cmp x0, #0 + ASM_ASSERT(ne) +#endif + ldr x0, [x0, #CPU_DATA_CPU_OPS_PTR] + ldr x0, [x0, #CPU_EXTRA1_FUNC] + /* + * If the reserved function pointer is NULL, this CPU + * is unaffected by CVE-2017-5715 so bail out. + */ + cmp x0, #0 + beq 1f + br x0 +1: + mov x0, #ERRATA_NOT_APPLIES + ret +endfunc check_workaround_cve_2017_5715 |