arch/powerpc/include/asm/feature-fixups.h

   1 /* SPDX-License-Identifier: GPL-2.0-or-later */
   2 #ifndef __ASM_POWERPC_FEATURE_FIXUPS_H
   3 #define __ASM_POWERPC_FEATURE_FIXUPS_H
   4
   5 #include <asm/asm-const.h>
   6
   7 /*
   8  */
   9
  10 /*
  11  * Feature section common macros
  12  *
  13  * Note that the entries now contain offsets between the table entry
  14  * and the code rather than absolute code pointers in order to be
  15  * useable with the vdso shared library. There is also an assumption
  16  * that values will be negative, that is, the fixup table has to be
  17  * located after the code it fixes up.
  18  */
  19 #if defined(CONFIG_PPC64) && !defined(__powerpc64__)
  20 /* 64 bits kernel, 32 bits code (ie. vdso32) */
  21 #define FTR_ENTRY_LONG          .8byte
  22 #define FTR_ENTRY_OFFSET        .long 0xffffffff; .long
  23 #elif defined(CONFIG_PPC64)
  24 #define FTR_ENTRY_LONG          .8byte
  25 #define FTR_ENTRY_OFFSET        .8byte
  26 #else
  27 #define FTR_ENTRY_LONG          .long
  28 #define FTR_ENTRY_OFFSET        .long
  29 #endif
  30
  31 #define START_FTR_SECTION(label)        label##1:
  32
  33 #define FTR_SECTION_ELSE_NESTED(label)                  \
  34 label##2:                                               \
  35         .pushsection __ftr_alt_##label,"a";             \
  36         .align 2;                                       \
  37 label##3:
  38
  39
  40 #ifndef CONFIG_CC_IS_CLANG
  41 #define CHECK_ALT_SIZE(else_size, body_size)                    \
  42         .ifgt (else_size) - (body_size);                        \
  43         .error "Feature section else case larger than body";    \
  44         .endif;
  45 #else
  46 /*
  47  * If we use the ifgt syntax above, clang's assembler complains about the
  48  * expression being non-absolute when the code appears in an inline assembly
  49  * statement.
  50  * As a workaround use an .org directive that has no effect if the else case
  51  * instructions are smaller than the body, but fails otherwise.
  52  */
  53 #define CHECK_ALT_SIZE(else_size, body_size)                    \
  54         .org . + ((else_size) > (body_size));
  55 #endif
  56
  57 #define MAKE_FTR_SECTION_ENTRY(msk, val, label, sect)           \
  58 label##4:                                                       \
  59         .popsection;                                            \
  60         .pushsection sect,"a";                                  \
  61         .align 3;                                               \
  62 label##5:                                                       \
  63         FTR_ENTRY_LONG msk;                                     \
  64         FTR_ENTRY_LONG val;                                     \
  65         FTR_ENTRY_OFFSET label##1b-label##5b;                   \
  66         FTR_ENTRY_OFFSET label##2b-label##5b;                   \
  67         FTR_ENTRY_OFFSET label##3b-label##5b;                   \
  68         FTR_ENTRY_OFFSET label##4b-label##5b;                   \
  69         CHECK_ALT_SIZE((label##4b-label##3b), (label##2b-label##1b)); \
  70         .popsection;
  71
  72
  73 /* CPU feature dependent sections */
  74 #define BEGIN_FTR_SECTION_NESTED(label) START_FTR_SECTION(label)
  75 #define BEGIN_FTR_SECTION               START_FTR_SECTION(97)
  76
  77 #define END_FTR_SECTION_NESTED(msk, val, label)                 \
  78         FTR_SECTION_ELSE_NESTED(label)                          \
  79         MAKE_FTR_SECTION_ENTRY(msk, val, label, __ftr_fixup)
  80
  81 #define END_FTR_SECTION(msk, val)               \
  82         END_FTR_SECTION_NESTED(msk, val, 97)
  83
  84 #define END_FTR_SECTION_NESTED_IFSET(msk, label)        \
  85         END_FTR_SECTION_NESTED((msk), (msk), label)
  86
  87 #define END_FTR_SECTION_IFSET(msk)      END_FTR_SECTION((msk), (msk))
  88 #define END_FTR_SECTION_IFCLR(msk)      END_FTR_SECTION((msk), 0)
  89
  90 /* CPU feature sections with alternatives, use BEGIN_FTR_SECTION to start */
  91 #define FTR_SECTION_ELSE        FTR_SECTION_ELSE_NESTED(97)
  92 #define ALT_FTR_SECTION_END_NESTED(msk, val, label)     \
  93         MAKE_FTR_SECTION_ENTRY(msk, val, label, __ftr_fixup)
  94 #define ALT_FTR_SECTION_END_NESTED_IFSET(msk, label)    \
  95         ALT_FTR_SECTION_END_NESTED(msk, msk, label)
  96 #define ALT_FTR_SECTION_END_NESTED_IFCLR(msk, label)    \
  97         ALT_FTR_SECTION_END_NESTED(msk, 0, label)
  98 #define ALT_FTR_SECTION_END(msk, val)   \
  99         ALT_FTR_SECTION_END_NESTED(msk, val, 97)
 100 #define ALT_FTR_SECTION_END_IFSET(msk)  \
 101         ALT_FTR_SECTION_END_NESTED_IFSET(msk, 97)
 102 #define ALT_FTR_SECTION_END_IFCLR(msk)  \
 103         ALT_FTR_SECTION_END_NESTED_IFCLR(msk, 97)
 104
 105 /* MMU feature dependent sections */
 106 #define BEGIN_MMU_FTR_SECTION_NESTED(label)     START_FTR_SECTION(label)
 107 #define BEGIN_MMU_FTR_SECTION                   START_FTR_SECTION(97)
 108
 109 #define END_MMU_FTR_SECTION_NESTED(msk, val, label)             \
 110         FTR_SECTION_ELSE_NESTED(label)                          \
 111         MAKE_FTR_SECTION_ENTRY(msk, val, label, __mmu_ftr_fixup)
 112
 113 #define END_MMU_FTR_SECTION(msk, val)           \
 114         END_MMU_FTR_SECTION_NESTED(msk, val, 97)
 115
 116 #define END_MMU_FTR_SECTION_NESTED_IFSET(msk, label)    \
 117         END_MMU_FTR_SECTION_NESTED((msk), (msk), label)
 118
 119 #define END_MMU_FTR_SECTION_NESTED_IFCLR(msk, label)    \
 120         END_MMU_FTR_SECTION_NESTED((msk), 0, label)
 121
 122 #define END_MMU_FTR_SECTION_IFSET(msk)  END_MMU_FTR_SECTION((msk), (msk))
 123 #define END_MMU_FTR_SECTION_IFCLR(msk)  END_MMU_FTR_SECTION((msk), 0)
 124
 125 /* MMU feature sections with alternatives, use BEGIN_FTR_SECTION to start */
 126 #define MMU_FTR_SECTION_ELSE_NESTED(label)      FTR_SECTION_ELSE_NESTED(label)
 127 #define MMU_FTR_SECTION_ELSE    MMU_FTR_SECTION_ELSE_NESTED(97)
 128 #define ALT_MMU_FTR_SECTION_END_NESTED(msk, val, label) \
 129         MAKE_FTR_SECTION_ENTRY(msk, val, label, __mmu_ftr_fixup)
 130 #define ALT_MMU_FTR_SECTION_END_NESTED_IFSET(msk, label)        \
 131         ALT_MMU_FTR_SECTION_END_NESTED(msk, msk, label)
 132 #define ALT_MMU_FTR_SECTION_END_NESTED_IFCLR(msk, label)        \
 133         ALT_MMU_FTR_SECTION_END_NESTED(msk, 0, label)
 134 #define ALT_MMU_FTR_SECTION_END(msk, val)       \
 135         ALT_MMU_FTR_SECTION_END_NESTED(msk, val, 97)
 136 #define ALT_MMU_FTR_SECTION_END_IFSET(msk)      \
 137         ALT_MMU_FTR_SECTION_END_NESTED_IFSET(msk, 97)
 138 #define ALT_MMU_FTR_SECTION_END_IFCLR(msk)      \
 139         ALT_MMU_FTR_SECTION_END_NESTED_IFCLR(msk, 97)
 140
 141 /* Firmware feature dependent sections */
 142 #define BEGIN_FW_FTR_SECTION_NESTED(label)      START_FTR_SECTION(label)
 143 #define BEGIN_FW_FTR_SECTION                    START_FTR_SECTION(97)
 144
 145 #define END_FW_FTR_SECTION_NESTED(msk, val, label)              \
 146         FTR_SECTION_ELSE_NESTED(label)                          \
 147         MAKE_FTR_SECTION_ENTRY(msk, val, label, __fw_ftr_fixup)
 148
 149 #define END_FW_FTR_SECTION(msk, val)            \
 150         END_FW_FTR_SECTION_NESTED(msk, val, 97)
 151
 152 #define END_FW_FTR_SECTION_IFSET(msk)   END_FW_FTR_SECTION((msk), (msk))
 153 #define END_FW_FTR_SECTION_IFCLR(msk)   END_FW_FTR_SECTION((msk), 0)
 154
 155 /* Firmware feature sections with alternatives */
 156 #define FW_FTR_SECTION_ELSE_NESTED(label)       FTR_SECTION_ELSE_NESTED(label)
 157 #define FW_FTR_SECTION_ELSE     FTR_SECTION_ELSE_NESTED(97)
 158 #define ALT_FW_FTR_SECTION_END_NESTED(msk, val, label)  \
 159         MAKE_FTR_SECTION_ENTRY(msk, val, label, __fw_ftr_fixup)
 160 #define ALT_FW_FTR_SECTION_END_NESTED_IFSET(msk, label) \
 161         ALT_FW_FTR_SECTION_END_NESTED(msk, msk, label)
 162 #define ALT_FW_FTR_SECTION_END_NESTED_IFCLR(msk, label) \
 163         ALT_FW_FTR_SECTION_END_NESTED(msk, 0, label)
 164 #define ALT_FW_FTR_SECTION_END(msk, val)        \
 165         ALT_FW_FTR_SECTION_END_NESTED(msk, val, 97)
 166 #define ALT_FW_FTR_SECTION_END_IFSET(msk)       \
 167         ALT_FW_FTR_SECTION_END_NESTED_IFSET(msk, 97)
 168 #define ALT_FW_FTR_SECTION_END_IFCLR(msk)       \
 169         ALT_FW_FTR_SECTION_END_NESTED_IFCLR(msk, 97)
 170
 171 #ifndef __ASSEMBLY__
 172
 173 #define ASM_FTR_IF(section_if, section_else, msk, val)  \
 174         stringify_in_c(BEGIN_FTR_SECTION)                       \
 175         section_if "; "                                         \
 176         stringify_in_c(FTR_SECTION_ELSE)                        \
 177         section_else "; "                                       \
 178         stringify_in_c(ALT_FTR_SECTION_END((msk), (val)))
 179
 180 #define ASM_FTR_IFSET(section_if, section_else, msk)    \
 181         ASM_FTR_IF(section_if, section_else, (msk), (msk))
 182
 183 #define ASM_FTR_IFCLR(section_if, section_else, msk)    \
 184         ASM_FTR_IF(section_if, section_else, (msk), 0)
 185
 186 #define ASM_MMU_FTR_IF(section_if, section_else, msk, val)      \
 187         stringify_in_c(BEGIN_MMU_FTR_SECTION)                   \
 188         section_if "; "                                         \
 189         stringify_in_c(MMU_FTR_SECTION_ELSE)                    \
 190         section_else "; "                                       \
 191         stringify_in_c(ALT_MMU_FTR_SECTION_END((msk), (val)))
 192
 193 #define ASM_MMU_FTR_IFSET(section_if, section_else, msk)        \
 194         ASM_MMU_FTR_IF(section_if, section_else, (msk), (msk))
 195
 196 #define ASM_MMU_FTR_IFCLR(section_if, section_else, msk)        \
 197         ASM_MMU_FTR_IF(section_if, section_else, (msk), 0)
 198
 199 #endif /* __ASSEMBLY__ */
 200
 201 /* LWSYNC feature sections */
 202 #define START_LWSYNC_SECTION(label)     label##1:
 203 #define MAKE_LWSYNC_SECTION_ENTRY(label, sect)          \
 204 label##2:                                               \
 205         .pushsection sect,"a";                          \
 206         .align 2;                                       \
 207 label##3:                                               \
 208         FTR_ENTRY_OFFSET label##1b-label##3b;           \
 209         .popsection;
 210
 211 #define STF_ENTRY_BARRIER_FIXUP_SECTION                 \
 212 953:                                                    \
 213         .pushsection __stf_entry_barrier_fixup,"a";     \
 214         .align 2;                                       \
 215 954:                                                    \
 216         FTR_ENTRY_OFFSET 953b-954b;                     \
 217         .popsection;
 218
 219 #define STF_EXIT_BARRIER_FIXUP_SECTION                  \
 220 955:                                                    \
 221         .pushsection __stf_exit_barrier_fixup,"a";      \
 222         .align 2;                                       \
 223 956:                                                    \
 224         FTR_ENTRY_OFFSET 955b-956b;                     \
 225         .popsection;
 226
 227 #define UACCESS_FLUSH_FIXUP_SECTION                     \
 228 959:                                                    \
 229         .pushsection __uaccess_flush_fixup,"a";         \
 230         .align 2;                                       \
 231 960:                                                    \
 232         FTR_ENTRY_OFFSET 959b-960b;                     \
 233         .popsection;
 234
 235 #define ENTRY_FLUSH_FIXUP_SECTION                       \
 236 957:                                                    \
 237         .pushsection __entry_flush_fixup,"a";           \
 238         .align 2;                                       \
 239 958:                                                    \
 240         FTR_ENTRY_OFFSET 957b-958b;                     \
 241         .popsection;
 242
 243 #define RFI_FLUSH_FIXUP_SECTION                         \
 244 951:                                                    \
 245         .pushsection __rfi_flush_fixup,"a";             \
 246         .align 2;                                       \
 247 952:                                                    \
 248         FTR_ENTRY_OFFSET 951b-952b;                     \
 249         .popsection;
 250
 251 #define NOSPEC_BARRIER_FIXUP_SECTION                    \
 252 953:                                                    \
 253         .pushsection __barrier_nospec_fixup,"a";        \
 254         .align 2;                                       \
 255 954:                                                    \
 256         FTR_ENTRY_OFFSET 953b-954b;                     \
 257         .popsection;
 258
 259 #define START_BTB_FLUSH_SECTION                 \
 260 955:                                                    \
 261
 262 #define END_BTB_FLUSH_SECTION                   \
 263 956:                                                    \
 264         .pushsection __btb_flush_fixup,"a";     \
 265         .align 2;                                                       \
 266 957:                                            \
 267         FTR_ENTRY_OFFSET 955b-957b;                     \
 268         FTR_ENTRY_OFFSET 956b-957b;                     \
 269         .popsection;
 270
 271 #ifndef __ASSEMBLY__
 272 #include <linux/types.h>
 273
 274 extern long stf_barrier_fallback;
 275 extern long entry_flush_fallback;
 276 extern long __start___stf_entry_barrier_fixup, __stop___stf_entry_barrier_fixup;
 277 extern long __start___stf_exit_barrier_fixup, __stop___stf_exit_barrier_fixup;
 278 extern long __start___uaccess_flush_fixup, __stop___uaccess_flush_fixup;
 279 extern long __start___entry_flush_fixup, __stop___entry_flush_fixup;
 280 extern long __start___rfi_flush_fixup, __stop___rfi_flush_fixup;
 281 extern long __start___barrier_nospec_fixup, __stop___barrier_nospec_fixup;
 282 extern long __start__btb_flush_fixup, __stop__btb_flush_fixup;
 283
 284 void apply_feature_fixups(void);
 285 void setup_feature_keys(void);
 286 #endif
 287
 288 #endif /* __ASM_POWERPC_FEATURE_FIXUPS_H */