1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Copyright (C) 2021 Sifive. 4 */ 5 6 #ifndef __ASM_ALTERNATIVE_H 7 #define __ASM_ALTERNATIVE_H 8 9 #include <asm/alternative-macros.h> 10 11 #ifndef __ASSEMBLY__ 12 13 #ifdef CONFIG_RISCV_ALTERNATIVE 14 15 #include <linux/init.h> 16 #include <linux/kernel.h> 17 #include <linux/types.h> 18 #include <linux/stddef.h> 19 #include <asm/hwcap.h> 20 21 #define PATCH_ID_CPUFEATURE_ID(p) lower_16_bits(p) 22 #define PATCH_ID_CPUFEATURE_VALUE(p) upper_16_bits(p) 23 24 #define RISCV_ALTERNATIVES_BOOT 0 /* alternatives applied during regular boot */ 25 #define RISCV_ALTERNATIVES_MODULE 1 /* alternatives applied during module-init */ 26 #define RISCV_ALTERNATIVES_EARLY_BOOT 2 /* alternatives applied before mmu start */ 27 28 /* add the relative offset to the address of the offset to get the absolute address */ 29 #define __ALT_PTR(a, f) ((void *)&(a)->f + (a)->f) 30 #define ALT_OLD_PTR(a) __ALT_PTR(a, old_offset) 31 #define ALT_ALT_PTR(a) __ALT_PTR(a, alt_offset) 32 33 void probe_vendor_features(unsigned int cpu); 34 void __init apply_boot_alternatives(void); 35 void __init apply_early_boot_alternatives(void); 36 void apply_module_alternatives(void *start, size_t length); 37 38 void riscv_alternative_fix_offsets(void *alt_ptr, unsigned int len, 39 int patch_offset); 40 41 struct alt_entry { 42 s32 old_offset; /* offset relative to original instruction or data */ 43 s32 alt_offset; /* offset relative to replacement instruction or data */ 44 u16 vendor_id; /* CPU vendor ID */ 45 u16 alt_len; /* The replacement size */ 46 u32 patch_id; /* The patch ID (erratum ID or cpufeature ID) */ 47 }; 48 49 void sifive_errata_patch_func(struct alt_entry *begin, struct alt_entry *end, 50 unsigned long archid, unsigned long impid, 51 unsigned int stage); 52 void thead_errata_patch_func(struct alt_entry *begin, struct alt_entry *end, 53 unsigned long archid, unsigned long impid, 54 unsigned int stage); 55 56 void thead_feature_probe_func(unsigned int cpu, unsigned long archid, 57 unsigned long impid); 58 59 void riscv_cpufeature_patch_func(struct alt_entry *begin, struct alt_entry *end, 60 unsigned int stage); 61 62 #else /* CONFIG_RISCV_ALTERNATIVE */ 63 64 static inline void probe_vendor_features(unsigned int cpu) { } 65 static inline void apply_boot_alternatives(void) { } 66 static inline void apply_early_boot_alternatives(void) { } 67 static inline void apply_module_alternatives(void *start, size_t length) { } 68 69 #endif /* CONFIG_RISCV_ALTERNATIVE */ 70 71 #endif 72 #endif 73