arch/powerpc/include/asm/head-64.h

   1 #ifndef _ASM_POWERPC_HEAD_64_H
   2 #define _ASM_POWERPC_HEAD_64_H
   3
   4 #include <asm/cache.h>
   5
   6 /*
   7  * We can't do CPP stringification and concatination directly into the section
   8  * name for some reason, so these macros can do it for us.
   9  */
  10 .macro define_ftsec name
  11         .section ".head.text.\name\()","ax",@progbits
  12 .endm
  13 .macro define_data_ftsec name
  14         .section ".head.data.\name\()","a",@progbits
  15 .endm
  16 .macro use_ftsec name
  17         .section ".head.text.\name\()"
  18 .endm
  19
  20 /*
  21  * Fixed (location) sections are used by opening fixed sections and emitting
  22  * fixed section entries into them before closing them. Multiple fixed sections
  23  * can be open at any time.
  24  *
  25  * Each fixed section created in a .S file must have corresponding linkage
  26  * directives including location, added to  arch/powerpc/kernel/vmlinux.lds.S
  27  *
  28  * For each fixed section, code is generated into it in the order which it
  29  * appears in the source.  Fixed section entries can be placed at a fixed
  30  * location within the section using _LOCATION postifx variants. These must
  31  * be ordered according to their relative placements within the section.
  32  *
  33  * OPEN_FIXED_SECTION(section_name, start_address, end_address)
  34  * FIXED_SECTION_ENTRY_BEGIN(section_name, label1)
  35  *
  36  * USE_FIXED_SECTION(section_name)
  37  * label3:
  38  *     li  r10,128
  39  *     mv  r11,r10
  40
  41  * FIXED_SECTION_ENTRY_BEGIN_LOCATION(section_name, label2, start_address)
  42  * FIXED_SECTION_ENTRY_END_LOCATION(section_name, label2, end_address)
  43  * CLOSE_FIXED_SECTION(section_name)
  44  *
  45  * ZERO_FIXED_SECTION can be used to emit zeroed data.
  46  *
  47  * Troubleshooting:
  48  * - If the build dies with "Error: attempt to move .org backwards" at
  49  *   CLOSE_FIXED_SECTION() or elsewhere, there may be something
  50  *   unexpected being added there. Remove the '. = x_len' line, rebuild, and
  51  *   check what is pushing the section down.
  52  * - If the build dies in linking, check arch/powerpc/kernel/vmlinux.lds.S
  53  *   for instructions.
  54  * - If the kernel crashes or hangs in very early boot, it could be linker
  55  *   stubs at the start of the main text.
  56  */
  57
  58 #define OPEN_FIXED_SECTION(sname, start, end)                   \
  59         sname##_start = (start);                                \
  60         sname##_end = (end);                                    \
  61         sname##_len = (end) - (start);                          \
  62         define_ftsec sname;                                     \
  63         . = 0x0;                                                \
  64 start_##sname:
  65
  66 #define OPEN_TEXT_SECTION(start)                                \
  67         text_start = (start);                                   \
  68         .section ".text","ax",@progbits;                        \
  69         . = 0x0;                                                \
  70 start_text:
  71
  72 #define ZERO_FIXED_SECTION(sname, start, end)                   \
  73         sname##_start = (start);                                \
  74         sname##_end = (end);                                    \
  75         sname##_len = (end) - (start);                          \
  76         define_data_ftsec sname;                                \
  77         . = 0x0;                                                \
  78         . = sname##_len;
  79
  80 #define USE_FIXED_SECTION(sname)                                \
  81         fs_label = start_##sname;                               \
  82         fs_start = sname##_start;                               \
  83         use_ftsec sname;
  84
  85 #define USE_TEXT_SECTION()                                      \
  86         fs_label = start_text;                                  \
  87         fs_start = text_start;                                  \
  88         .text
  89
  90 #define CLOSE_FIXED_SECTION(sname)                              \
  91         USE_FIXED_SECTION(sname);                               \
  92         . = sname##_len;                                        \
  93 end_##sname:
  94
  95
  96 #define __FIXED_SECTION_ENTRY_BEGIN(sname, name, __align)       \
  97         USE_FIXED_SECTION(sname);                               \
  98         .align __align;                                         \
  99         .global name;                                           \
 100 name:
 101
 102 #define FIXED_SECTION_ENTRY_BEGIN(sname, name)                  \
 103         __FIXED_SECTION_ENTRY_BEGIN(sname, name, 0)
 104
 105 #define FIXED_SECTION_ENTRY_BEGIN_LOCATION(sname, name, start)          \
 106         USE_FIXED_SECTION(sname);                               \
 107         name##_start = (start);                                 \
 108         .if (start) < sname##_start;                            \
 109         .error "Fixed section underflow";                       \
 110         .abort;                                                 \
 111         .endif;                                                 \
 112         . = (start) - sname##_start;                            \
 113         .global name;                                           \
 114 name:
 115
 116 #define FIXED_SECTION_ENTRY_END_LOCATION(sname, name, end)              \
 117         .if (end) > sname##_end;                                \
 118         .error "Fixed section overflow";                        \
 119         .abort;                                                 \
 120         .endif;                                                 \
 121         .if (. - name > end - name##_start);                    \
 122         .error "Fixed entry overflow";                          \
 123         .abort;                                                 \
 124         .endif;                                                 \
 125         . = ((end) - sname##_start);                            \
 126
 127
 128 /*
 129  * These macros are used to change symbols in other fixed sections to be
 130  * absolute or related to our current fixed section.
 131  *
 132  * - DEFINE_FIXED_SYMBOL / FIXED_SYMBOL_ABS_ADDR is used to find the
 133  *   absolute address of a symbol within a fixed section, from any section.
 134  *
 135  * - ABS_ADDR is used to find the absolute address of any symbol, from within
 136  *   a fixed section.
 137  */
 138 #define DEFINE_FIXED_SYMBOL(label)                              \
 139         label##_absolute = (label - fs_label + fs_start)
 140
 141 #define FIXED_SYMBOL_ABS_ADDR(label)                            \
 142         (label##_absolute)
 143
 144 #define ABS_ADDR(label) (label - fs_label + fs_start)
 145
 146 /*
 147  * Following are the BOOK3S exception handler helper macros.
 148  * Handlers come in a number of types, and each type has a number of varieties.
 149  *
 150  * EXC_REAL_*        - real, unrelocated exception vectors
 151  * EXC_VIRT_*        - virt (AIL), unrelocated exception vectors
 152  * TRAMP_REAL_*   - real, unrelocated helpers (virt can call these)
 153  * TRAMP_VIRT_*  - virt, unreloc helpers (in practice, real can use)
 154  * TRAMP_KVM         - KVM handlers that get put into real, unrelocated
 155  * EXC_COMMON_*  - virt, relocated common handlers
 156  *
 157  * The EXC handlers are given a name, and branch to name_common, or the
 158  * appropriate KVM or masking function. Vector handler verieties are as
 159  * follows:
 160  *
 161  * EXC_{REAL|VIRT}_BEGIN/END - used to open-code the exception
 162  *
 163  * EXC_{REAL|VIRT}  - standard exception
 164  *
 165  * EXC_{REAL|VIRT}_suffix
 166  *     where _suffix is:
 167  *   - _MASKABLE               - maskable exception
 168  *   - _OOL                    - out of line with trampoline to common handler
 169  *   - _HV                     - HV exception
 170  *
 171  * There can be combinations, e.g., EXC_VIRT_OOL_MASKABLE_HV
 172  *
 173  * The one unusual case is __EXC_REAL_OOL_HV_DIRECT, which is
 174  * an OOL vector that branches to a specified handler rather than the usual
 175  * trampoline that goes to common. It, and other underscore macros, should
 176  * be used with care.
 177  *
 178  * KVM handlers come in the following verieties:
 179  * TRAMP_KVM
 180  * TRAMP_KVM_SKIP
 181  * TRAMP_KVM_HV
 182  * TRAMP_KVM_HV_SKIP
 183  *
 184  * COMMON handlers come in the following verieties:
 185  * EXC_COMMON_BEGIN/END - used to open-code the handler
 186  * EXC_COMMON
 187  * EXC_COMMON_ASYNC
 188  * EXC_COMMON_HV
 189  *
 190  * TRAMP_REAL and TRAMP_VIRT can be used with BEGIN/END. KVM
 191  * and OOL handlers are implemented as types of TRAMP and TRAMP_VIRT handlers.
 192  */
 193
 194 #define EXC_REAL_BEGIN(name, start, end)                        \
 195         FIXED_SECTION_ENTRY_BEGIN_LOCATION(real_vectors, exc_real_##start##_##name, start)
 196
 197 #define EXC_REAL_END(name, start, end)                  \
 198         FIXED_SECTION_ENTRY_END_LOCATION(real_vectors, exc_real_##start##_##name, end)
 199
 200 #define EXC_VIRT_BEGIN(name, start, end)                        \
 201         FIXED_SECTION_ENTRY_BEGIN_LOCATION(virt_vectors, exc_virt_##start##_##name, start)
 202
 203 #define EXC_VIRT_END(name, start, end)                  \
 204         FIXED_SECTION_ENTRY_END_LOCATION(virt_vectors, exc_virt_##start##_##name, end)
 205
 206 #define EXC_COMMON_BEGIN(name)                                  \
 207         USE_TEXT_SECTION();                                             \
 208         .align  7;                                                      \
 209         .global name;                                                   \
 210         DEFINE_FIXED_SYMBOL(name);                                      \
 211 name:
 212
 213 #define TRAMP_REAL_BEGIN(name)                                  \
 214         FIXED_SECTION_ENTRY_BEGIN(real_trampolines, name)
 215
 216 #define TRAMP_VIRT_BEGIN(name)                                  \
 217         FIXED_SECTION_ENTRY_BEGIN(virt_trampolines, name)
 218
 219 #ifdef CONFIG_KVM_BOOK3S_64_HANDLER
 220 #define TRAMP_KVM_BEGIN(name)                                           \
 221         TRAMP_REAL_BEGIN(name)
 222 #else
 223 #define TRAMP_KVM_BEGIN(name)
 224 #endif
 225
 226 #define EXC_REAL_NONE(start, end)                               \
 227         FIXED_SECTION_ENTRY_BEGIN_LOCATION(real_vectors, exc_real_##start##_##unused, start); \
 228         FIXED_SECTION_ENTRY_END_LOCATION(real_vectors, exc_real_##start##_##unused, end)
 229
 230 #define EXC_VIRT_NONE(start, end)                               \
 231         FIXED_SECTION_ENTRY_BEGIN_LOCATION(virt_vectors, exc_virt_##start##_##unused, start); \
 232         FIXED_SECTION_ENTRY_END_LOCATION(virt_vectors, exc_virt_##start##_##unused, end);
 233
 234
 235 #define EXC_REAL(name, start, end)                              \
 236         EXC_REAL_BEGIN(name, start, end);                       \
 237         STD_EXCEPTION_PSERIES(start, name##_common);                    \
 238         EXC_REAL_END(name, start, end);
 239
 240 #define EXC_VIRT(name, start, end, realvec)                     \
 241         EXC_VIRT_BEGIN(name, start, end);                       \
 242         STD_RELON_EXCEPTION_PSERIES(start, realvec, name##_common);     \
 243         EXC_VIRT_END(name, start, end);
 244
 245 #define EXC_REAL_MASKABLE(name, start, end)                     \
 246         EXC_REAL_BEGIN(name, start, end);                       \
 247         MASKABLE_EXCEPTION_PSERIES(start, start, name##_common);        \
 248         EXC_REAL_END(name, start, end);
 249
 250 #define EXC_VIRT_MASKABLE(name, start, end, realvec)            \
 251         EXC_VIRT_BEGIN(name, start, end);                       \
 252         MASKABLE_RELON_EXCEPTION_PSERIES(start, realvec, name##_common); \
 253         EXC_VIRT_END(name, start, end);
 254
 255 #define EXC_REAL_HV(name, start, end)                   \
 256         EXC_REAL_BEGIN(name, start, end);                       \
 257         STD_EXCEPTION_HV(start, start, name##_common);                  \
 258         EXC_REAL_END(name, start, end);
 259
 260 #define EXC_VIRT_HV(name, start, end, realvec)          \
 261         EXC_VIRT_BEGIN(name, start, end);                       \
 262         STD_RELON_EXCEPTION_HV(start, realvec, name##_common);          \
 263         EXC_VIRT_END(name, start, end);
 264
 265 #define __EXC_REAL_OOL(name, start, end)                        \
 266         EXC_REAL_BEGIN(name, start, end);                       \
 267         __OOL_EXCEPTION(start, label, tramp_real_##name);               \
 268         EXC_REAL_END(name, start, end);
 269
 270 #define __TRAMP_REAL_REAL_OOL(name, vec)                                \
 271         TRAMP_REAL_BEGIN(tramp_real_##name);                            \
 272         STD_EXCEPTION_PSERIES_OOL(vec, name##_common);                  \
 273
 274 #define EXC_REAL_OOL(name, start, end)                  \
 275         __EXC_REAL_OOL(name, start, end);                       \
 276         __TRAMP_REAL_REAL_OOL(name, start);
 277
 278 #define __EXC_REAL_OOL_MASKABLE(name, start, end)               \
 279         __EXC_REAL_OOL(name, start, end);
 280
 281 #define __TRAMP_REAL_REAL_OOL_MASKABLE(name, vec)                       \
 282         TRAMP_REAL_BEGIN(tramp_real_##name);                            \
 283         MASKABLE_EXCEPTION_PSERIES_OOL(vec, name##_common);             \
 284
 285 #define EXC_REAL_OOL_MASKABLE(name, start, end)         \
 286         __EXC_REAL_OOL_MASKABLE(name, start, end);              \
 287         __TRAMP_REAL_REAL_OOL_MASKABLE(name, start);
 288
 289 #define __EXC_REAL_OOL_HV_DIRECT(name, start, end, handler)     \
 290         EXC_REAL_BEGIN(name, start, end);                       \
 291         __OOL_EXCEPTION(start, label, handler);                         \
 292         EXC_REAL_END(name, start, end);
 293
 294 #define __EXC_REAL_OOL_HV(name, start, end)                     \
 295         __EXC_REAL_OOL(name, start, end);
 296
 297 #define __TRAMP_REAL_REAL_OOL_HV(name, vec)                             \
 298         TRAMP_REAL_BEGIN(tramp_real_##name);                            \
 299         STD_EXCEPTION_HV_OOL(vec, name##_common);                       \
 300
 301 #define EXC_REAL_OOL_HV(name, start, end)                       \
 302         __EXC_REAL_OOL_HV(name, start, end);                    \
 303         __TRAMP_REAL_REAL_OOL_HV(name, start);
 304
 305 #define __EXC_REAL_OOL_MASKABLE_HV(name, start, end)            \
 306         __EXC_REAL_OOL(name, start, end);
 307
 308 #define __TRAMP_REAL_REAL_OOL_MASKABLE_HV(name, vec)                    \
 309         TRAMP_REAL_BEGIN(tramp_real_##name);                            \
 310         MASKABLE_EXCEPTION_HV_OOL(vec, name##_common);                  \
 311
 312 #define EXC_REAL_OOL_MASKABLE_HV(name, start, end)              \
 313         __EXC_REAL_OOL_MASKABLE_HV(name, start, end);   \
 314         __TRAMP_REAL_REAL_OOL_MASKABLE_HV(name, start);
 315
 316 #define __EXC_VIRT_OOL(name, start, end)                        \
 317         EXC_VIRT_BEGIN(name, start, end);                       \
 318         __OOL_EXCEPTION(start, label, tramp_virt_##name);               \
 319         EXC_VIRT_END(name, start, end);
 320
 321 #define __TRAMP_REAL_VIRT_OOL(name, realvec)                            \
 322         TRAMP_VIRT_BEGIN(tramp_virt_##name);                    \
 323         STD_RELON_EXCEPTION_PSERIES_OOL(realvec, name##_common);        \
 324
 325 #define EXC_VIRT_OOL(name, start, end, realvec)         \
 326         __EXC_VIRT_OOL(name, start, end);                       \
 327         __TRAMP_REAL_VIRT_OOL(name, realvec);
 328
 329 #define __EXC_VIRT_OOL_MASKABLE(name, start, end)               \
 330         __EXC_VIRT_OOL(name, start, end);
 331
 332 #define __TRAMP_REAL_VIRT_OOL_MASKABLE(name, realvec)           \
 333         TRAMP_VIRT_BEGIN(tramp_virt_##name);                    \
 334         MASKABLE_RELON_EXCEPTION_PSERIES_OOL(realvec, name##_common);   \
 335
 336 #define EXC_VIRT_OOL_MASKABLE(name, start, end, realvec)        \
 337         __EXC_VIRT_OOL_MASKABLE(name, start, end);              \
 338         __TRAMP_REAL_VIRT_OOL_MASKABLE(name, realvec);
 339
 340 #define __EXC_VIRT_OOL_HV(name, start, end)                     \
 341         __EXC_VIRT_OOL(name, start, end);
 342
 343 #define __TRAMP_REAL_VIRT_OOL_HV(name, realvec)                 \
 344         TRAMP_VIRT_BEGIN(tramp_virt_##name);                    \
 345         STD_RELON_EXCEPTION_HV_OOL(realvec, name##_common);             \
 346
 347 #define EXC_VIRT_OOL_HV(name, start, end, realvec)              \
 348         __EXC_VIRT_OOL_HV(name, start, end);                    \
 349         __TRAMP_REAL_VIRT_OOL_HV(name, realvec);
 350
 351 #define __EXC_VIRT_OOL_MASKABLE_HV(name, start, end)            \
 352         __EXC_VIRT_OOL(name, start, end);
 353
 354 #define __TRAMP_REAL_VIRT_OOL_MASKABLE_HV(name, realvec)                \
 355         TRAMP_VIRT_BEGIN(tramp_virt_##name);                    \
 356         MASKABLE_RELON_EXCEPTION_HV_OOL(realvec, name##_common);        \
 357
 358 #define EXC_VIRT_OOL_MASKABLE_HV(name, start, end, realvec)     \
 359         __EXC_VIRT_OOL_MASKABLE_HV(name, start, end);   \
 360         __TRAMP_REAL_VIRT_OOL_MASKABLE_HV(name, realvec);
 361
 362 #define TRAMP_KVM(area, n)                                              \
 363         TRAMP_KVM_BEGIN(do_kvm_##n);                                    \
 364         KVM_HANDLER(area, EXC_STD, n);                                  \
 365
 366 #define TRAMP_KVM_SKIP(area, n)                                         \
 367         TRAMP_KVM_BEGIN(do_kvm_##n);                                    \
 368         KVM_HANDLER_SKIP(area, EXC_STD, n);                             \
 369
 370 /*
 371  * HV variant exceptions get the 0x2 bit added to their trap number.
 372  */
 373 #define TRAMP_KVM_HV(area, n)                                           \
 374         TRAMP_KVM_BEGIN(do_kvm_H##n);                                   \
 375         KVM_HANDLER(area, EXC_HV, n + 0x2);                             \
 376
 377 #define TRAMP_KVM_HV_SKIP(area, n)                                      \
 378         TRAMP_KVM_BEGIN(do_kvm_H##n);                                   \
 379         KVM_HANDLER_SKIP(area, EXC_HV, n + 0x2);                        \
 380
 381 #define EXC_COMMON(name, realvec, hdlr)                         \
 382         EXC_COMMON_BEGIN(name);                                 \
 383         STD_EXCEPTION_COMMON(realvec, name, hdlr);                      \
 384
 385 #define EXC_COMMON_ASYNC(name, realvec, hdlr)                   \
 386         EXC_COMMON_BEGIN(name);                                 \
 387         STD_EXCEPTION_COMMON_ASYNC(realvec, name, hdlr);                \
 388
 389 #define EXC_COMMON_HV(name, realvec, hdlr)                              \
 390         EXC_COMMON_BEGIN(name);                                 \
 391         STD_EXCEPTION_COMMON(realvec + 0x2, name, hdlr);                \
 392
 393 #endif  /* _ASM_POWERPC_HEAD_64_H */