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         mfcr    r9;                                                     \
 119         extra(vec);                                                     \
 120         std     r11,area+EX_R11(r13);                                   \
 121         std     r12,area+EX_R12(r13);                                   \
 122         GET_SCRATCH0(r10);                                              \
 123         std     r10,area+EX_R13(r13)
 124 #define EXCEPTION_PROLOG_1(area, extra, vec)                            \
 125         __EXCEPTION_PROLOG_1(area, extra, vec)
 126
 127 #define __EXCEPTION_PROLOG_PSERIES_1(label, h)                          \
 128         ld      r12,PACAKBASE(r13);     /* get high part of &label */   \
 129         ld      r10,PACAKMSR(r13);      /* get MSR value for kernel */  \
 130         mfspr   r11,SPRN_##h##SRR0;     /* save SRR0 */                 \
 131         LOAD_HANDLER(r12,label)                                         \
 132         mtspr   SPRN_##h##SRR0,r12;                                     \
 133         mfspr   r12,SPRN_##h##SRR1;     /* and SRR1 */                  \
 134         mtspr   SPRN_##h##SRR1,r10;                                     \
 135         h##rfid;                                                        \
 136         b       .       /* prevent speculative execution */
 137 #define EXCEPTION_PROLOG_PSERIES_1(label, h)                            \
 138         __EXCEPTION_PROLOG_PSERIES_1(label, h)
 139
 140 #define EXCEPTION_PROLOG_PSERIES(area, label, h, extra, vec)            \
 141         EXCEPTION_PROLOG_1(area, extra, vec);                           \
 142         EXCEPTION_PROLOG_PSERIES_1(label, h);
 143
 144 #define __KVMTEST(n)                                                    \
 145         lbz     r10,HSTATE_IN_GUEST(r13);                       \
 146         cmpwi   r10,0;                                                  \
 147         bne     do_kvm_##n
 148
 149 #define __KVM_HANDLER(area, h, n)                                       \
 150 do_kvm_##n:                                                             \
 151         ld      r10,area+EX_R10(r13);                                   \
 152         stw     r9,HSTATE_SCRATCH1(r13);                        \
 153         ld      r9,area+EX_R9(r13);                                     \
 154         std     r12,HSTATE_SCRATCH0(r13);                       \
 155         li      r12,n;                                                  \
 156         b       kvmppc_interrupt
 157
 158 #define __KVM_HANDLER_SKIP(area, h, n)                                  \
 159 do_kvm_##n:                                                             \
 160         cmpwi   r10,KVM_GUEST_MODE_SKIP;                                \
 161         ld      r10,area+EX_R10(r13);                                   \
 162         beq     89f;                                                    \
 163         stw     r9,HSTATE_SCRATCH1(r13);                        \
 164         ld      r9,area+EX_R9(r13);                                     \
 165         std     r12,HSTATE_SCRATCH0(r13);                       \
 166         li      r12,n;                                                  \
 167         b       kvmppc_interrupt;                                       \
 168 89:     mtocrf  0x80,r9;                                                \
 169         ld      r9,area+EX_R9(r13);                                     \
 170         b       kvmppc_skip_##h##interrupt
 171
 172 #ifdef CONFIG_KVM_BOOK3S_64_HANDLER
 173 #define KVMTEST(n)                      __KVMTEST(n)
 174 #define KVM_HANDLER(area, h, n)         __KVM_HANDLER(area, h, n)
 175 #define KVM_HANDLER_SKIP(area, h, n)    __KVM_HANDLER_SKIP(area, h, n)
 176
 177 #else
 178 #define KVMTEST(n)
 179 #define KVM_HANDLER(area, h, n)
 180 #define KVM_HANDLER_SKIP(area, h, n)
 181 #endif
 182
 183 #ifdef CONFIG_KVM_BOOK3S_PR
 184 #define KVMTEST_PR(n)                   __KVMTEST(n)
 185 #define KVM_HANDLER_PR(area, h, n)      __KVM_HANDLER(area, h, n)
 186 #define KVM_HANDLER_PR_SKIP(area, h, n) __KVM_HANDLER_SKIP(area, h, n)
 187
 188 #else
 189 #define KVMTEST_PR(n)
 190 #define KVM_HANDLER_PR(area, h, n)
 191 #define KVM_HANDLER_PR_SKIP(area, h, n)
 192 #endif
 193
 194 #define NOTEST(n)
 195
 196 /*
 197  * The common exception prolog is used for all except a few exceptions
 198  * such as a segment miss on a kernel address.  We have to be prepared
 199  * to take another exception from the point where we first touch the
 200  * kernel stack onwards.
 201  *
 202  * On entry r13 points to the paca, r9-r13 are saved in the paca,
 203  * r9 contains the saved CR, r11 and r12 contain the saved SRR0 and
 204  * SRR1, and relocation is on.
 205  */
 206 #define EXCEPTION_PROLOG_COMMON(n, area)                                   \
 207         andi.   r10,r12,MSR_PR;         /* See if coming from user      */ \
 208         mr      r10,r1;                 /* Save r1                      */ \
 209         subi    r1,r1,INT_FRAME_SIZE;   /* alloc frame on kernel stack  */ \
 210         beq-    1f;                                                        \
 211         ld      r1,PACAKSAVE(r13);      /* kernel stack to use          */ \
 212 1:      cmpdi   cr1,r1,0;               /* check if r1 is in userspace  */ \
 213         blt+    cr1,3f;                 /* abort if it is               */ \
 214         li      r1,(n);                 /* will be reloaded later       */ \
 215         sth     r1,PACA_TRAP_SAVE(r13);                                    \
 216         std     r3,area+EX_R3(r13);                                        \
 217         addi    r3,r13,area;            /* r3 -> where regs are saved*/    \
 218         b       bad_stack;                                                 \
 219 3:      std     r9,_CCR(r1);            /* save CR in stackframe        */ \
 220         std     r11,_NIP(r1);           /* save SRR0 in stackframe      */ \
 221         std     r12,_MSR(r1);           /* save SRR1 in stackframe      */ \
 222         std     r10,0(r1);              /* make stack chain pointer     */ \
 223         std     r0,GPR0(r1);            /* save r0 in stackframe        */ \
 224         std     r10,GPR1(r1);           /* save r1 in stackframe        */ \
 225         ACCOUNT_CPU_USER_ENTRY(r9, r10);                                   \
 226         std     r2,GPR2(r1);            /* save r2 in stackframe        */ \
 227         SAVE_4GPRS(3, r1);              /* save r3 - r6 in stackframe   */ \
 228         SAVE_2GPRS(7, r1);              /* save r7, r8 in stackframe    */ \
 229         ld      r9,area+EX_R9(r13);     /* move r9, r10 to stackframe   */ \
 230         ld      r10,area+EX_R10(r13);                                      \
 231         std     r9,GPR9(r1);                                               \
 232         std     r10,GPR10(r1);                                             \
 233         ld      r9,area+EX_R11(r13);    /* move r11 - r13 to stackframe */ \
 234         ld      r10,area+EX_R12(r13);                                      \
 235         ld      r11,area+EX_R13(r13);                                      \
 236         std     r9,GPR11(r1);                                              \
 237         std     r10,GPR12(r1);                                             \
 238         std     r11,GPR13(r1);                                             \
 239         BEGIN_FTR_SECTION_NESTED(66);                                      \
 240         ld      r10,area+EX_CFAR(r13);                                     \
 241         std     r10,ORIG_GPR3(r1);                                         \
 242         END_FTR_SECTION_NESTED(CPU_FTR_CFAR, CPU_FTR_CFAR, 66);            \
 243         ld      r2,PACATOC(r13);        /* get kernel TOC into r2       */ \
 244         mflr    r9;                     /* save LR in stackframe        */ \
 245         std     r9,_LINK(r1);                                              \
 246         mfctr   r10;                    /* save CTR in stackframe       */ \
 247         std     r10,_CTR(r1);                                              \
 248         lbz     r10,PACASOFTIRQEN(r13);                            \
 249         mfspr   r11,SPRN_XER;           /* save XER in stackframe       */ \
 250         std     r10,SOFTE(r1);                                             \
 251         std     r11,_XER(r1);                                              \
 252         li      r9,(n)+1;                                                  \
 253         std     r9,_TRAP(r1);           /* set trap number              */ \
 254         li      r10,0;                                                     \
 255         ld      r11,exception_marker@toc(r2);                              \
 256         std     r10,RESULT(r1);         /* clear regs->result           */ \
 257         std     r11,STACK_FRAME_OVERHEAD-16(r1); /* mark the frame      */ \
 258         ACCOUNT_STOLEN_TIME
 259
 260 /*
 261  * Exception vectors.
 262  */
 263 #define STD_EXCEPTION_PSERIES(loc, vec, label)          \
 264         . = loc;                                        \
 265         .globl label##_pSeries;                         \
 266 label##_pSeries:                                        \
 267         HMT_MEDIUM;                                     \
 268         SET_SCRATCH0(r13);              /* save r13 */          \
 269         EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, label##_common,    \
 270                                  EXC_STD, KVMTEST_PR, vec)
 271
 272 #define STD_EXCEPTION_HV(loc, vec, label)               \
 273         . = loc;                                        \
 274         .globl label##_hv;                              \
 275 label##_hv:                                             \
 276         HMT_MEDIUM;                                     \
 277         SET_SCRATCH0(r13);      /* save r13 */                  \
 278         EXCEPTION_PROLOG_PSERIES(PACA_EXGEN, label##_common,    \
 279                                  EXC_HV, KVMTEST, vec)
 280
 281 #define STD_RELON_EXCEPTION_PSERIES(loc, vec, label)    \
 282         . = loc;                                        \
 283         .globl label##_relon_pSeries;                   \
 284 label##_relon_pSeries:                                  \
 285         HMT_MEDIUM;                                     \
 286         /* No guest interrupts come through here */     \
 287         SET_SCRATCH0(r13);              /* save r13 */  \
 288         EXCEPTION_RELON_PROLOG_PSERIES(PACA_EXGEN, label##_common, \
 289                                        EXC_STD, KVMTEST_PR, vec)
 290
 291 #define STD_RELON_EXCEPTION_HV(loc, vec, label)         \
 292         . = loc;                                        \
 293         .globl label##_relon_hv;                        \
 294 label##_relon_hv:                                       \
 295         HMT_MEDIUM;                                     \
 296         /* No guest interrupts come through here */     \
 297         SET_SCRATCH0(r13);      /* save r13 */          \
 298         EXCEPTION_RELON_PROLOG_PSERIES(PACA_EXGEN, label##_common, \
 299                                        EXC_HV, KVMTEST, vec)
 300
 301 /* This associate vector numbers with bits in paca->irq_happened */
 302 #define SOFTEN_VALUE_0x500      PACA_IRQ_EE
 303 #define SOFTEN_VALUE_0x502      PACA_IRQ_EE
 304 #define SOFTEN_VALUE_0x900      PACA_IRQ_DEC
 305 #define SOFTEN_VALUE_0x982      PACA_IRQ_DEC
 306
 307 #define __SOFTEN_TEST(h, vec)                                           \
 308         lbz     r10,PACASOFTIRQEN(r13);                                 \
 309         cmpwi   r10,0;                                                  \
 310         li      r10,SOFTEN_VALUE_##vec;                                 \
 311         beq     masked_##h##interrupt
 312 #define _SOFTEN_TEST(h, vec)    __SOFTEN_TEST(h, vec)
 313
 314 #define SOFTEN_TEST_PR(vec)                                             \
 315         KVMTEST_PR(vec);                                                \
 316         _SOFTEN_TEST(EXC_STD, vec)
 317
 318 #define SOFTEN_TEST_HV(vec)                                             \
 319         KVMTEST(vec);                                                   \
 320         _SOFTEN_TEST(EXC_HV, vec)
 321
 322 #define SOFTEN_TEST_HV_201(vec)                                         \
 323         KVMTEST(vec);                                                   \
 324         _SOFTEN_TEST(EXC_STD, vec)
 325
 326 #define SOFTEN_NOTEST_PR(vec)           _SOFTEN_TEST(EXC_STD, vec)
 327 #define SOFTEN_NOTEST_HV(vec)           _SOFTEN_TEST(EXC_HV, vec)
 328
 329 #define __MASKABLE_EXCEPTION_PSERIES(vec, label, h, extra)              \
 330         HMT_MEDIUM;                                                     \
 331         SET_SCRATCH0(r13);    /* save r13 */                            \
 332         __EXCEPTION_PROLOG_1(PACA_EXGEN, extra, vec);           \
 333         EXCEPTION_PROLOG_PSERIES_1(label##_common, h);
 334 #define _MASKABLE_EXCEPTION_PSERIES(vec, label, h, extra)               \
 335         __MASKABLE_EXCEPTION_PSERIES(vec, label, h, extra)
 336
 337 #define MASKABLE_EXCEPTION_PSERIES(loc, vec, label)                     \
 338         . = loc;                                                        \
 339         .globl label##_pSeries;                                         \
 340 label##_pSeries:                                                        \
 341         _MASKABLE_EXCEPTION_PSERIES(vec, label,                         \
 342                                     EXC_STD, SOFTEN_TEST_PR)
 343
 344 #define MASKABLE_EXCEPTION_HV(loc, vec, label)                          \
 345         . = loc;                                                        \
 346         .globl label##_hv;                                              \
 347 label##_hv:                                                             \
 348         _MASKABLE_EXCEPTION_PSERIES(vec, label,                         \
 349                                     EXC_HV, SOFTEN_TEST_HV)
 350
 351 #define __MASKABLE_RELON_EXCEPTION_PSERIES(vec, label, h, extra)        \
 352         HMT_MEDIUM;                                                     \
 353         SET_SCRATCH0(r13);    /* save r13 */                            \
 354         __EXCEPTION_PROLOG_1(PACA_EXGEN, extra, vec);           \
 355         EXCEPTION_RELON_PROLOG_PSERIES_1(label##_common, h);
 356 #define _MASKABLE_RELON_EXCEPTION_PSERIES(vec, label, h, extra) \
 357         __MASKABLE_RELON_EXCEPTION_PSERIES(vec, label, h, extra)
 358
 359 #define MASKABLE_RELON_EXCEPTION_PSERIES(loc, vec, label)               \
 360         . = loc;                                                        \
 361         .globl label##_relon_pSeries;                                   \
 362 label##_relon_pSeries:                                                  \
 363         _MASKABLE_RELON_EXCEPTION_PSERIES(vec, label,                   \
 364                                           EXC_STD, SOFTEN_NOTEST_PR)
 365
 366 #define MASKABLE_RELON_EXCEPTION_HV(loc, vec, label)                    \
 367         . = loc;                                                        \
 368         .globl label##_relon_hv;                                        \
 369 label##_relon_hv:                                                       \
 370         _MASKABLE_RELON_EXCEPTION_PSERIES(vec, label,                   \
 371                                           EXC_HV, SOFTEN_NOTEST_HV)
 372
 373 /*
 374  * Our exception common code can be passed various "additions"
 375  * to specify the behaviour of interrupts, whether to kick the
 376  * runlatch, etc...
 377  */
 378
 379 /* Exception addition: Hard disable interrupts */
 380 #define DISABLE_INTS    SOFT_DISABLE_INTS(r10,r11)
 381
 382 #define ADD_NVGPRS                              \
 383         bl      .save_nvgprs
 384
 385 #define RUNLATCH_ON                             \
 386 BEGIN_FTR_SECTION                               \
 387         CURRENT_THREAD_INFO(r3, r1);            \
 388         ld      r4,TI_LOCAL_FLAGS(r3);          \
 389         andi.   r0,r4,_TLF_RUNLATCH;            \
 390         beql    ppc64_runlatch_on_trampoline;   \
 391 END_FTR_SECTION_IFSET(CPU_FTR_CTRL)
 392
 393 #define EXCEPTION_COMMON(trap, label, hdlr, ret, additions)     \
 394         .align  7;                                              \
 395         .globl label##_common;                                  \
 396 label##_common:                                                 \
 397         EXCEPTION_PROLOG_COMMON(trap, PACA_EXGEN);              \
 398         additions;                                              \
 399         addi    r3,r1,STACK_FRAME_OVERHEAD;                     \
 400         bl      hdlr;                                           \
 401         b       ret
 402
 403 #define STD_EXCEPTION_COMMON(trap, label, hdlr)                 \
 404         EXCEPTION_COMMON(trap, label, hdlr, ret_from_except,    \
 405                          ADD_NVGPRS;DISABLE_INTS)
 406
 407 /*
 408  * Like STD_EXCEPTION_COMMON, but for exceptions that can occur
 409  * in the idle task and therefore need the special idle handling
 410  * (finish nap and runlatch)
 411  */
 412 #define STD_EXCEPTION_COMMON_ASYNC(trap, label, hdlr)             \
 413         EXCEPTION_COMMON(trap, label, hdlr, ret_from_except_lite, \
 414                          FINISH_NAP;RUNLATCH_ON;DISABLE_INTS)
 415
 416 /*
 417  * When the idle code in power4_idle puts the CPU into NAP mode,
 418  * it has to do so in a loop, and relies on the external interrupt
 419  * and decrementer interrupt entry code to get it out of the loop.
 420  * It sets the _TLF_NAPPING bit in current_thread_info()->local_flags
 421  * to signal that it is in the loop and needs help to get out.
 422  */
 423 #ifdef CONFIG_PPC_970_NAP
 424 #define FINISH_NAP                              \
 425 BEGIN_FTR_SECTION                               \
 426         CURRENT_THREAD_INFO(r11, r1);           \
 427         ld      r9,TI_LOCAL_FLAGS(r11);         \
 428         andi.   r10,r9,_TLF_NAPPING;            \
 429         bnel    power4_fixup_nap;               \
 430 END_FTR_SECTION_IFSET(CPU_FTR_CAN_NAP)
 431 #else
 432 #define FINISH_NAP
 433 #endif
 434
 435 #endif  /* _ASM_POWERPC_EXCEPTION_H */