1/* SPDX-License-Identifier: GPL-2.0 */ 2#ifndef __ASM_ALTERNATIVE_MACROS_H 3#define __ASM_ALTERNATIVE_MACROS_H 4 5#ifdef CONFIG_RISCV_ALTERNATIVE 6 7#ifdef __ASSEMBLY__ 8 9.macro ALT_ENTRY oldptr newptr vendor_id patch_id new_len 10 .4byte \oldptr - . 11 .4byte \newptr - . 12 .2byte \vendor_id 13 .2byte \new_len 14 .4byte \patch_id 15.endm 16 17.macro ALT_NEW_CONTENT vendor_id, patch_id, enable = 1, new_c 18 .if \enable 19 .pushsection .alternative, "a" 20 ALT_ENTRY 886b, 888f, \vendor_id, \patch_id, 889f - 888f 21 .popsection 22 .subsection 1 23888 : 24 .option push 25 .option norvc 26 .option norelax 27 \new_c 28 .option pop 29889 : 30 .org . - (889b - 888b) + (887b - 886b) 31 .org . - (887b - 886b) + (889b - 888b) 32 .previous 33 .endif 34.endm 35 36.macro ALTERNATIVE_CFG old_c, new_c, vendor_id, patch_id, enable 37886 : 38 .option push 39 .option norvc 40 .option norelax 41 \old_c 42 .option pop 43887 : 44 ALT_NEW_CONTENT \vendor_id, \patch_id, \enable, "\new_c" 45.endm 46 47.macro ALTERNATIVE_CFG_2 old_c, new_c_1, vendor_id_1, patch_id_1, enable_1, \ 48 new_c_2, vendor_id_2, patch_id_2, enable_2 49 ALTERNATIVE_CFG "\old_c", "\new_c_1", \vendor_id_1, \patch_id_1, \enable_1 50 ALT_NEW_CONTENT \vendor_id_2, \patch_id_2, \enable_2, "\new_c_2" 51.endm 52 53#define __ALTERNATIVE_CFG(...) ALTERNATIVE_CFG __VA_ARGS__ 54#define __ALTERNATIVE_CFG_2(...) ALTERNATIVE_CFG_2 __VA_ARGS__ 55 56#else /* !__ASSEMBLY__ */ 57 58#include <asm/asm.h> 59#include <linux/stringify.h> 60 61#define ALT_ENTRY(oldptr, newptr, vendor_id, patch_id, newlen) \ 62 ".4byte ((" oldptr ") - .) \n" \ 63 ".4byte ((" newptr ") - .) \n" \ 64 ".2byte " vendor_id "\n" \ 65 ".2byte " newlen "\n" \ 66 ".4byte " patch_id "\n" 67 68#define ALT_NEW_CONTENT(vendor_id, patch_id, enable, new_c) \ 69 ".if " __stringify(enable) " == 1\n" \ 70 ".pushsection .alternative, \"a\"\n" \ 71 ALT_ENTRY("886b", "888f", __stringify(vendor_id), __stringify(patch_id), "889f - 888f") \ 72 ".popsection\n" \ 73 ".subsection 1\n" \ 74 "888 :\n" \ 75 ".option push\n" \ 76 ".option norvc\n" \ 77 ".option norelax\n" \ 78 new_c "\n" \ 79 ".option pop\n" \ 80 "889 :\n" \ 81 ".org . - (887b - 886b) + (889b - 888b)\n" \ 82 ".org . - (889b - 888b) + (887b - 886b)\n" \ 83 ".previous\n" \ 84 ".endif\n" 85 86#define __ALTERNATIVE_CFG(old_c, new_c, vendor_id, patch_id, enable) \ 87 "886 :\n" \ 88 ".option push\n" \ 89 ".option norvc\n" \ 90 ".option norelax\n" \ 91 old_c "\n" \ 92 ".option pop\n" \ 93 "887 :\n" \ 94 ALT_NEW_CONTENT(vendor_id, patch_id, enable, new_c) 95 96#define __ALTERNATIVE_CFG_2(old_c, new_c_1, vendor_id_1, patch_id_1, enable_1, \ 97 new_c_2, vendor_id_2, patch_id_2, enable_2) \ 98 __ALTERNATIVE_CFG(old_c, new_c_1, vendor_id_1, patch_id_1, enable_1) \ 99 ALT_NEW_CONTENT(vendor_id_2, patch_id_2, enable_2, new_c_2) 100 101#endif /* __ASSEMBLY__ */ 102 103#define _ALTERNATIVE_CFG(old_c, new_c, vendor_id, patch_id, CONFIG_k) \ 104 __ALTERNATIVE_CFG(old_c, new_c, vendor_id, patch_id, IS_ENABLED(CONFIG_k)) 105 106#define _ALTERNATIVE_CFG_2(old_c, new_c_1, vendor_id_1, patch_id_1, CONFIG_k_1, \ 107 new_c_2, vendor_id_2, patch_id_2, CONFIG_k_2) \ 108 __ALTERNATIVE_CFG_2(old_c, new_c_1, vendor_id_1, patch_id_1, IS_ENABLED(CONFIG_k_1), \ 109 new_c_2, vendor_id_2, patch_id_2, IS_ENABLED(CONFIG_k_2)) 110 111#else /* CONFIG_RISCV_ALTERNATIVE */ 112#ifdef __ASSEMBLY__ 113 114.macro ALTERNATIVE_CFG old_c 115 \old_c 116.endm 117 118#define _ALTERNATIVE_CFG(old_c, ...) \ 119 ALTERNATIVE_CFG old_c 120 121#define _ALTERNATIVE_CFG_2(old_c, ...) \ 122 ALTERNATIVE_CFG old_c 123 124#else /* !__ASSEMBLY__ */ 125 126#define __ALTERNATIVE_CFG(old_c) \ 127 old_c "\n" 128 129#define _ALTERNATIVE_CFG(old_c, ...) \ 130 __ALTERNATIVE_CFG(old_c) 131 132#define _ALTERNATIVE_CFG_2(old_c, ...) \ 133 __ALTERNATIVE_CFG(old_c) 134 135#endif /* __ASSEMBLY__ */ 136#endif /* CONFIG_RISCV_ALTERNATIVE */ 137 138/* 139 * Usage: 140 * ALTERNATIVE(old_content, new_content, vendor_id, patch_id, CONFIG_k) 141 * in the assembly code. Otherwise, 142 * asm(ALTERNATIVE(old_content, new_content, vendor_id, patch_id, CONFIG_k)); 143 * 144 * old_content: The old content which is probably replaced with new content. 145 * new_content: The new content. 146 * vendor_id: The CPU vendor ID. 147 * patch_id: The patch ID (erratum ID or cpufeature ID). 148 * CONFIG_k: The Kconfig of this patch ID. When Kconfig is disabled, the old 149 * content will always be executed. 150 */ 151#define ALTERNATIVE(old_content, new_content, vendor_id, patch_id, CONFIG_k) \ 152 _ALTERNATIVE_CFG(old_content, new_content, vendor_id, patch_id, CONFIG_k) 153 154/* 155 * A vendor wants to replace an old_content, but another vendor has used 156 * ALTERNATIVE() to patch its customized content at the same location. In 157 * this case, this vendor can create a new macro ALTERNATIVE_2() based 158 * on the following sample code and then replace ALTERNATIVE() with 159 * ALTERNATIVE_2() to append its customized content. 160 */ 161#define ALTERNATIVE_2(old_content, new_content_1, vendor_id_1, patch_id_1, CONFIG_k_1, \ 162 new_content_2, vendor_id_2, patch_id_2, CONFIG_k_2) \ 163 _ALTERNATIVE_CFG_2(old_content, new_content_1, vendor_id_1, patch_id_1, CONFIG_k_1, \ 164 new_content_2, vendor_id_2, patch_id_2, CONFIG_k_2) 165 166#endif 167