arch/powerpc/include/asm/exception-64s.h

   1 #ifndef _ASM_POWERPC_EXCEPTION_H
   2 #define _ASM_POWERPC_EXCEPTION_H
   3 /*
   4  * Extracted from head_64.S
   5  *
   6  *  PowerPC version
   7  *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
   8  *
   9  *  Rewritten by Cort Dougan (cort@cs.nmt.edu) for PReP
  10  *    Copyright (C) 1996 Cort Dougan <cort@cs.nmt.edu>
  11  *  Adapted for Power Macintosh by Paul Mackerras.
  12  *  Low-level exception handlers and MMU support
  13  *  rewritten by Paul Mackerras.
  14  *    Copyright (C) 1996 Paul Mackerras.
  15  *
  16  *  Adapted for 64bit PowerPC by Dave Engebretsen, Peter Bergner, and
  17  *    Mike Corrigan {engebret|bergner|mikejc}@us.ibm.com
  18  *
  19  *  This file contains the low-level support and setup for the
  20  *  PowerPC-64 platform, including trap and interrupt dispatch.
  21  *
  22  *  This program is free software; you can redistribute it and/or
  23  *  modify it under the terms of the GNU General Public License
  24  *  as published by the Free Software Foundation; either version
  25  *  2 of the License, or (at your option) any later version.
  26  */
  27 /*
  28  * The following macros define the code that appears as
  29  * the prologue to each of the exception handlers.  They
  30  * are split into two parts to allow a single kernel binary
  31  * to be used for pSeries and iSeries.
  32  *
  33  * We make as much of the exception code common between native
  34  * exception handlers (including pSeries LPAR) and iSeries LPAR
  35  * implementations as possible.
  36  */
  37
  38 #define EX_R9           0
  39 #define EX_R10          8
  40 #define EX_R11          16
  41 #define EX_R12          24
  42 #define EX_R13          32
  43 #define EX_SRR0         40
  44 #define EX_DAR          48
  45 #define EX_DSISR        56
  46 #define EX_CCR          60
  47 #define EX_R3           64
  48 #define EX_LR           72
  49 #define EX_CFAR         80
  50
  51 #ifdef CONFIG_RELOCATABLE
  52 #define EXCEPTION_RELON_PROLOG_PSERIES_1(label, h)                      \
  53         ld      r12,PACAKBASE(r13);     /* get high part of &label */   \
  54         mfspr   r11,SPRN_##h##SRR0;     /* save SRR0 */                 \
  55         LOAD_HANDLER(r12,label);                                        \
  56         mtlr    r12;                                                    \
  57         mfspr   r12,SPRN_##h##SRR1;     /* and SRR1 */                  \
  58         li      r10,MSR_RI;                                             \
  59         mtmsrd  r10,1;                  /* Set RI (EE=0) */             \
  60         blr;
  61 #else
  62 /* If not relocatable, we can jump directly -- and save messing with LR */
  63 #define EXCEPTION_RELON_PROLOG_PSERIES_1(label, h)                      \
  64         mfspr   r11,SPRN_##h##SRR0;     /* save SRR0 */                 \
  65         mfspr   r12,SPRN_##h##SRR1;     /* and SRR1 */                  \
  66         li      r10,MSR_RI;                                             \
  67         mtmsrd  r10,1;                  /* Set RI (EE=0) */             \
  68         b       label;
  69 #endif
  70
  71 /*
  72  * As EXCEPTION_PROLOG_PSERIES(), except we've already got relocation on
  73  * so no need to rfid.  Save lr in case we're CONFIG_RELOCATABLE, in which
  74  * case EXCEPTION_RELON_PROLOG_PSERIES_1 will be using lr.
  75  */
  76 #define EXCEPTION_RELON_PROLOG_PSERIES(area, label, h, extra, vec)      \
  77         EXCEPTION_PROLOG_1(area, extra, vec);                           \
  78         EXCEPTION_RELON_PROLOG_PSERIES_1(label, h)
  79
  80 /*
  81  * We're short on space and time in the exception prolog, so we can't
  82  * use the normal SET_REG_IMMEDIATE macro. Normally we just need the
  83  * low halfword of the address, but for Kdump we need the whole low
  84  * word.
  85  */
  86 #define LOAD_HANDLER(reg, label)                                        \
  87         /* Handlers must be within 64K of kbase, which must be 64k aligned */ \
  88         ori     reg,reg,(label)-_stext; /* virt addr of handler ... */
  89
  90 /* Exception register prefixes */
  91 #define EXC_HV  H
  92 #define EXC_STD
  93
  94 #if defined(CONFIG_RELOCATABLE)
  95 /*
  96  * If we support interrupts with relocation on AND we're a relocatable
  97  * kernel, we need to use LR to get to the 2nd level handler.  So, save/restore
  98  * it when required.
  99  */
 100 #define SAVE_LR(reg, area)      mflr    reg ;   std     reg,area+EX_LR(r13)
 101 #define GET_LR(reg, area)                       ld      reg,area+EX_LR(r13)
 102 #define RESTORE_LR(reg, area)   ld      reg,area+EX_LR(r13) ; mtlr reg
 103 #else
 104 /* ...else LR is unused and in register. */
 105 #define SAVE_LR(reg, area)
 106 #define GET_LR(reg, area)       mflr    reg
 107 #define RESTORE_LR(reg, area)
 108 #endif
 109
 110 #define __EXCEPTION_PROLOG_1(area, extra, vec)                          \
 111         GET_PACA(r13);                                                  \
 112         std     r9,area+EX_R9(r13);     /* save r9 - r12 */             \
 113         std     r10,area+EX_R10(r13);                                   \
 114         BEGIN_FTR_SECTION_NESTED(66);                                   \
 115         mfspr   r10,SPRN_CFAR;                                          \
 116         std     r10,area+EX_CFAR(r13);                                  \
 117         END_FTR_SECTION_NESTED(CPU_FTR_CFAR, CPU_FTR_CFAR, 66);         \
 118         SAVE_LR(r10, area);                                             \
 119         mfcr    r9;                                                     \
 120         extra(vec);                                                     \
 121         std     r11,area+EX_R11(r13);                                   \
 122         std     r12,area+EX_R12(r13);                                   \
 123         GET_SCRATCH0(r10);                                              \
 124         std     r10,area+EX_R13(r13)
 125 #define EXCEPTION_PROLOG_1(area, extra, vec)                            \
 126         __EXCEPTION_PROLOG_1(area, extra, vec)
 127
 128 #define __EXCEPTION_PROLOG_PSERIES_1(label, h)                          \
 129         ld      r12,PACAKBASE(r13);     /* get high part of &label */   \
 130         ld      r10,PACAKMSR(r13);      /* get MSR value for kernel */  \
 131         mfspr   r11,SPRN_##h##SRR0;     /* save SRR0 */                 \
 132         LOAD_HANDLER(r12,label)                                         \
 133         mtspr   SPRN_##h##SRR0,r12;                                     \
 134         mfspr   r12,SPRN_##h##SRR1;     /* and SRR1 */                  \
 135         mtspr   SPRN_##h##SRR1,r10;                                     \
 136         h##rfid;                                                        \
 137         b       .       /* prevent speculative execution */
 138 #define EXCEPTION_PROLOG_PSERIES_1(label, h)                            \
 139         __EXCEPTION_PROLOG_PSERIES_1(label, h)
 140
 141 #define EXCEPTION_PROLOG_PSERIES(area, label, h, extra, vec)            \
 142         EXCEPTION_PROLOG_1(area, extra, vec);                           \
 143         EXCEPTION_PROLOG_PSERIES_1(label, h);
 144
 145 #define __KVMTEST(n)                                                    \
 146         lbz     r10,HSTATE_IN_GUEST(r13);                       \
 147         cmpwi   r10,0;                                                  \
 148         bne     do_kvm_##n
 149
 150 #define __KVM_HANDLER(area, h, n)                                       \
 151 do_kvm_##n:                                                             \
 152         ld      r10,area+EX_R10(r13);                                   \
 153         stw     r9,HSTATE_SCRATCH1(r13);                        \
 154         ld      r9,area+EX_R9(r13);                                     \
 155         std     r12,HSTATE_SCRATCH0(r13);                       \
 156         li      r12,n;                                                  \
 157         b       kvmppc_interrupt
 158
 159 #define __KVM_HANDLER_SKIP(area, h, n)                                  \
 160 do_kvm_##n:                                                             \
 161         cmpwi   r10,KVM_GUEST_MODE_SKIP;                                \
 162         ld      r10,area+EX_R10(r13);                                   \
 163         beq     89f;                                                    \
 164         stw     r9,HSTATE_SCRATCH1(r13);                        \
 165         ld      r9,area+EX_R9(r13);                                     \
 166         std     r12,HSTATE_SCRATCH0(r13);                       \
 167         li      r12,n;                                                  \
 168         b       kvmppc_interrupt;                                       \
 169 89:     mtocrf  0x80,r9;                                                \
 170         ld      r9,area+EX_R9(r13);                                     \
 171         b       kvmppc_skip_##h##interrupt
 172
 173 #ifdef CONFIG_KVM_BOOK3S_64_HANDLER
 174 #define KVMTEST(n)                      __KVMTEST(n)
 175 #define KVM_HANDLER(area, h, n)         __KVM_HANDLER(area, h, n)
 176 #define KVM_HANDLER_SKIP(area, h, n)    __KVM_HANDLER_SKIP(area, h, n)
 177
 178 #else
 179 #define KVMTEST(n)
 180 #define KVM_HANDLER(area, h, n)
 181 #define KVM_HANDLER_SKIP(area, h, n)
 182 #endif
 183
 184 #ifdef CONFIG_KVM_BOOK3S_PR
 185 #define KVMTEST_PR(n)                   __KVMTEST(n)
 186 #define KVM_HANDLER_PR(area, h, n)      __KVM_HANDLER(area, h, n)
 187 #define KVM_HANDLER_PR_SKIP(area, h, n) __KVM_HANDLER_SKIP(area, h, n)
 188
 189 #else
 190 #define KVMTEST_PR(n)
 191 #define KVM_HANDLER_PR(area, h, n)
 192 #define KVM_HANDLER_PR_SKIP(area, h, n)
 193 #endif
 194
 195 #define NOTEST(n)
 196
 197 /*
 198  * The common exception prolog is used for all except a few exceptions
 199  * such as a segment miss on a kernel address.  We have to be prepared
 200  * to take another exception from the point where we first touch the
 201  * kernel stack onwards.
 202  *
 203  * On entry r13 points to the paca, r9-r13 are saved in the paca,
 204  * r9 contains the saved CR, r11 and r12 contain the saved SRR0 and
 205  * SRR1, and relocation is on.
 206  */
 207 #define EXCEPTION_PROLOG_COMMON(n, area)                                   \
 208         andi.   r10,r12,MSR_PR;         /* See if coming from user      */ \
 209         mr      r10,r1;                 /* Save r1                      */ \
 210         subi    r1,r1,INT_FRAME_SIZE;   /* alloc frame on kernel stack  */ \
 211         beq-    1f;                                                        \
 212         ld      r1,PACAKSAVE(r13);      /* kernel stack to use          */ \
 213 1:      cmpdi   cr1,r1,0;               /* check if r1 is in userspace  */ \
 214         blt+    cr1,3f;                 /* abort if it is               */ \
 215         li      r1,(n);                 /* will be reloaded later       */ \
 216         sth     r1,PACA_TRAP_SAVE(r13);                                    \
 217         std     r3,area+EX_R3(r13);                                        \
 218         addi    r3,r13,area;            /* r3 -> where regs are saved*/    \
 219         RESTORE_LR(r1, area);                                              \
 220         b       bad_stack;                                                 \
 221 3:      std     r9,_CCR(r1);            /* save CR in stackframe        */ \
 222         std     r11,_NIP(r1);           /* save SRR0 in stackframe      */ \
 223         std     r12,_MSR(r1);           /* save SRR1 in stackframe      */ \
 224         std     r10,0(r1);              /* make stack chain pointer     */ \
 225         std     r0,GPR0(r1);            /* save r0 in stackframe        */ \
 226         std     r10,GPR1(r1);           /* save r1 in stackframe        */ \
 227         beq     4f;                     /* if from kernel mode          */ \
 228         ACCOUNT_CPU_USER_ENTRY(r9, r10);                                   \
 229 4:      std     r2,GPR2(r1);            /* save r2 in stackframe        */ \
 230         SAVE_4GPRS(3, r1);              /* save r3 - r6 in stackframe   */ \
 231         SAVE_2GPRS(7, r1);              /* save r7, r8 in stackframe    */ \
 232         ld      r9,area+EX_R9(r13);     /* move r9, r10 to stackframe   */ \
 233         ld      r10,area+EX_R10(r13);                                      \
 234         std     r9,GPR9(r1);                                               \
 235         std     r10,GPR10(r1);                                             \
 236         ld      r9,area+EX_R11(r13);    /* move r11 - r13 to stackframe */ \
 237         ld      r10,area+EX_R12(r13);                                      \
 238         ld      r11,area+EX_R13(r13);                                      \
 239         std     r9,GPR11(r1);                                              \
 240         std     r10,GPR12(r1);                                             \
 241         std     r11,GPR13(r1);                                             \
 242         BEGIN_FTR_SECTION_NESTED(66);                                      \
 243         ld      r10,area+EX_CFAR(r13);                                     \
 244         std     r10,ORIG_GPR3(r1);                                         \
 245         END_FTR_SECTION_NESTED(CPU_FTR_CFAR, CPU_FTR_CFAR, 66);            \
 246         GET_LR(r9,area);                /* Get LR, later save to stack  */ \
 247         ld      r2,PACATOC(r13);        /* get kernel TOC into r2       */ \
 248         std     r9,_LINK(r1);                                              \
 249         mfctr   r10;                    /* save CTR in stackframe       */ \
 250         std     r10,_CTR(r1);                                              \
 251         lbz     r10,PACASOFTIRQEN(r13);                            \
 252         mfspr   r11,SPRN_XER;           /* save XER in stackframe       */ \
 253         std     r10,SOFTE(r1);                                             \
 254         std     r11,_XER(r1);                                              \
 255         li      r9,(n)+1;                                                  \
 256         std     r9,_TRAP(r1);           /* set trap number              */ \
 257         li      r10,0;                                                     \
 258         ld      r11,exception_marker@toc(r2);                              \
 259         std     r10,RESULT(r1);         /* clear regs->result           */ \
 260         std     r11,STACK_FRAME_OVERHEAD-16(r1); /* mark the frame      */ \
 261         ACCOUNT_STOLEN_TIME
 262
 263 /*
 264  * Exception vectors.
 265  */
 266 #define STD_EXCEPTION_PSERIES(loc, vec, label)          \
 267         . = loc;                                        \
 268         .globl label##_pSeries;                         \
 269 label##_pSeries:                                        \
 270         HMT_MEDIUM;                                     \
 271         SET_SCRATCH0(r13);              /* save r13 */          \
 272         EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, label##_common,    \
 273                                  EXC_STD, KVMTEST_PR, vec)
 274
 275 #define STD_EXCEPTION_HV(loc, vec, label)               \
 276         . = loc;                                        \
 277         .globl label##_hv;                              \
 278 label##_hv:                                             \
 279         HMT_MEDIUM;                                     \
 280         SET_SCRATCH0(r13);      /* save r13 */                  \
 281         EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, label##_common,    \
 282                                  EXC_HV, KVMTEST, vec)
 283
 284 #define STD_RELON_EXCEPTION_PSERIES(loc, vec, label)    \
 285         . = loc;                                        \
 286         .globl label##_relon_pSeries;                   \
 287 label##_relon_pSeries:                                  \
 288         HMT_MEDIUM;                                     \
 289         /* No guest interrupts come through here */     \
 290         SET_SCRATCH0(r13);              /* save r13 */  \
 291         EXCEPTION_RELON_PROLOG_PSERIES(PACA_EXGEN, label##_common, \
 292                                        EXC_STD, KVMTEST_PR, vec)
 293
 294 #define STD_RELON_EXCEPTION_HV(loc, vec, label)         \
 295         . = loc;                                        \
 296         .globl label##_relon_hv;                        \
 297 label##_relon_hv:                                       \
 298         HMT_MEDIUM;                                     \
 299         /* No guest interrupts come through here */     \
 300         SET_SCRATCH0(r13);      /* save r13 */          \
 301         EXCEPTION_RELON_PROLOG_PSERIES(PACA_EXGEN, label##_common, \
 302                                        EXC_HV, KVMTEST, vec)
 303
 304 /* This associate vector numbers with bits in paca->irq_happened */
 305 #define SOFTEN_VALUE_0x500      PACA_IRQ_EE
 306 #define SOFTEN_VALUE_0x502      PACA_IRQ_EE
 307 #define SOFTEN_VALUE_0x900      PACA_IRQ_DEC
 308 #define SOFTEN_VALUE_0x982      PACA_IRQ_DEC
 309 #define SOFTEN_VALUE_0xa00      PACA_IRQ_DBELL
 310 #define SOFTEN_VALUE_0xe80      PACA_IRQ_DBELL
 311 #define SOFTEN_VALUE_0xe82      PACA_IRQ_DBELL
 312
 313 #define __SOFTEN_TEST(h, vec)                                           \
 314         lbz     r10,PACASOFTIRQEN(r13);                                 \
 315         cmpwi   r10,0;                                                  \
 316         li      r10,SOFTEN_VALUE_##vec;                                 \
 317         beq     masked_##h##interrupt
 318 #define _SOFTEN_TEST(h, vec)    __SOFTEN_TEST(h, vec)
 319
 320 #define SOFTEN_TEST_PR(vec)                                             \
 321         KVMTEST_PR(vec);                                                \
 322         _SOFTEN_TEST(EXC_STD, vec)
 323
 324 #define SOFTEN_TEST_HV(vec)                                             \
 325         KVMTEST(vec);                                                   \
 326         _SOFTEN_TEST(EXC_HV, vec)
 327
 328 #define SOFTEN_TEST_HV_201(vec)                                         \
 329         KVMTEST(vec);                                                   \
 330         _SOFTEN_TEST(EXC_STD, vec)
 331
 332 #define SOFTEN_NOTEST_PR(vec)           _SOFTEN_TEST(EXC_STD, vec)
 333 #define SOFTEN_NOTEST_HV(vec)           _SOFTEN_TEST(EXC_HV, vec)
 334
 335 #define __MASKABLE_EXCEPTION_PSERIES(vec, label, h, extra)              \
 336         HMT_MEDIUM;                                                     \
 337         SET_SCRATCH0(r13);    /* save r13 */                            \
 338         __EXCEPTION_PROLOG_1(PACA_EXGEN, extra, vec);           \
 339         EXCEPTION_PROLOG_PSERIES_1(label##_common, h);
 340 #define _MASKABLE_EXCEPTION_PSERIES(vec, label, h, extra)               \
 341         __MASKABLE_EXCEPTION_PSERIES(vec, label, h, extra)
 342
 343 #define MASKABLE_EXCEPTION_PSERIES(loc, vec, label)                     \
 344         . = loc;                                                        \
 345         .globl label##_pSeries;                                         \
 346 label##_pSeries:                                                        \
 347         _MASKABLE_EXCEPTION_PSERIES(vec, label,                         \
 348                                     EXC_STD, SOFTEN_TEST_PR)
 349
 350 #define MASKABLE_EXCEPTION_HV(loc, vec, label)                          \
 351         . = loc;                                                        \
 352         .globl label##_hv;                                              \
 353 label##_hv:                                                             \
 354         _MASKABLE_EXCEPTION_PSERIES(vec, label,                         \
 355                                     EXC_HV, SOFTEN_TEST_HV)
 356
 357 #define __MASKABLE_RELON_EXCEPTION_PSERIES(vec, label, h, extra)        \
 358         HMT_MEDIUM;                                                     \
 359         SET_SCRATCH0(r13);    /* save r13 */                            \
 360         __EXCEPTION_PROLOG_1(PACA_EXGEN, extra, vec);           \
 361         EXCEPTION_RELON_PROLOG_PSERIES_1(label##_common, h);
 362 #define _MASKABLE_RELON_EXCEPTION_PSERIES(vec, label, h, extra) \
 363         __MASKABLE_RELON_EXCEPTION_PSERIES(vec, label, h, extra)
 364
 365 #define MASKABLE_RELON_EXCEPTION_PSERIES(loc, vec, label)               \
 366         . = loc;                                                        \
 367         .globl label##_relon_pSeries;                                   \
 368 label##_relon_pSeries:                                                  \
 369         _MASKABLE_RELON_EXCEPTION_PSERIES(vec, label,                   \
 370                                           EXC_STD, SOFTEN_NOTEST_PR)
 371
 372 #define MASKABLE_RELON_EXCEPTION_HV(loc, vec, label)                    \
 373         . = loc;                                                        \
 374         .globl label##_relon_hv;                                        \
 375 label##_relon_hv:                                                       \
 376         _MASKABLE_RELON_EXCEPTION_PSERIES(vec, label,                   \
 377                                           EXC_HV, SOFTEN_NOTEST_HV)
 378
 379 /*
 380  * Our exception common code can be passed various "additions"
 381  * to specify the behaviour of interrupts, whether to kick the
 382  * runlatch, etc...
 383  */
 384
 385 /* Exception addition: Hard disable interrupts */
 386 #define DISABLE_INTS    SOFT_DISABLE_INTS(r10,r11)
 387
 388 #define ADD_NVGPRS                              \
 389         bl      .save_nvgprs
 390
 391 #define RUNLATCH_ON                             \
 392 BEGIN_FTR_SECTION                               \
 393         CURRENT_THREAD_INFO(r3, r1);            \
 394         ld      r4,TI_LOCAL_FLAGS(r3);          \
 395         andi.   r0,r4,_TLF_RUNLATCH;            \
 396         beql    ppc64_runlatch_on_trampoline;   \
 397 END_FTR_SECTION_IFSET(CPU_FTR_CTRL)
 398
 399 #define EXCEPTION_COMMON(trap, label, hdlr, ret, additions)     \
 400         .align  7;                                              \
 401         .globl label##_common;                                  \
 402 label##_common:                                                 \
 403         EXCEPTION_PROLOG_COMMON(trap, PACA_EXGEN);              \
 404         additions;                                              \
 405         addi    r3,r1,STACK_FRAME_OVERHEAD;                     \
 406         bl      hdlr;                                           \
 407         b       ret
 408
 409 #define STD_EXCEPTION_COMMON(trap, label, hdlr)                 \
 410         EXCEPTION_COMMON(trap, label, hdlr, ret_from_except,    \
 411                          ADD_NVGPRS;DISABLE_INTS)
 412
 413 /*
 414  * Like STD_EXCEPTION_COMMON, but for exceptions that can occur
 415  * in the idle task and therefore need the special idle handling
 416  * (finish nap and runlatch)
 417  */
 418 #define STD_EXCEPTION_COMMON_ASYNC(trap, label, hdlr)             \
 419         EXCEPTION_COMMON(trap, label, hdlr, ret_from_except_lite, \
 420                          FINISH_NAP;RUNLATCH_ON;DISABLE_INTS)
 421
 422 /*
 423  * When the idle code in power4_idle puts the CPU into NAP mode,
 424  * it has to do so in a loop, and relies on the external interrupt
 425  * and decrementer interrupt entry code to get it out of the loop.
 426  * It sets the _TLF_NAPPING bit in current_thread_info()->local_flags
 427  * to signal that it is in the loop and needs help to get out.
 428  */
 429 #ifdef CONFIG_PPC_970_NAP
 430 #define FINISH_NAP                              \
 431 BEGIN_FTR_SECTION                               \
 432         CURRENT_THREAD_INFO(r11, r1);           \
 433         ld      r9,TI_LOCAL_FLAGS(r11);         \
 434         andi.   r10,r9,_TLF_NAPPING;            \
 435         bnel    power4_fixup_nap;               \
 436 END_FTR_SECTION_IFSET(CPU_FTR_CAN_NAP)
 437 #else
 438 #define FINISH_NAP
 439 #endif
 440
 441 #endif  /* _ASM_POWERPC_EXCEPTION_H */