LXR linux/arch/powerpc/kernel/head

   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef __HEAD_BOOKE_H__
   3#define __HEAD_BOOKE_H__
   4
   5#include <asm/ptrace.h> /* for STACK_FRAME_REGS_MARKER */
   6#include <asm/kvm_asm.h>
   7#include <asm/kvm_booke_hv_asm.h>
   8
   9/*
  10 * Macros used for common Book-e exception handling
  11 */
  12
  13#define SET_IVOR(vector_number, vector_label)           \
  14                li      r26,vector_label@l;             \
  15                mtspr   SPRN_IVOR##vector_number,r26;   \
  16                sync
  17
  18#if (THREAD_SHIFT < 15)
  19#define ALLOC_STACK_FRAME(reg, val)                     \
  20        addi reg,reg,val
  21#else
  22#define ALLOC_STACK_FRAME(reg, val)                     \
  23        addis   reg,reg,val@ha;                         \
  24        addi    reg,reg,val@l
  25#endif
  26
  27/*
  28 * Macro used to get to thread save registers.
  29 * Note that entries 0-3 are used for the prolog code, and the remaining
  30 * entries are available for specific exception use in the event a handler
  31 * requires more than 4 scratch registers.
  32 */
  33#define THREAD_NORMSAVE(offset) (THREAD_NORMSAVES + (offset * 4))
  34
  35#define NORMAL_EXCEPTION_PROLOG(intno)                                               \
  36        mtspr   SPRN_SPRG_WSCRATCH0, r10;       /* save one register */      \
  37        mfspr   r10, SPRN_SPRG_THREAD;                                       \
  38        stw     r11, THREAD_NORMSAVE(0)(r10);                                \
  39        stw     r13, THREAD_NORMSAVE(2)(r10);                                \
  40        mfcr    r13;                    /* save CR in r13 for now          */\
  41        mfspr   r11, SPRN_SRR1;                                              \
  42        DO_KVM  BOOKE_INTERRUPT_##intno SPRN_SRR1;                           \
  43        andi.   r11, r11, MSR_PR;       /* check whether user or kernel    */\
  44        mr      r11, r1;                                                     \
  45        beq     1f;                                                          \
  46        /* if from user, start at top of this thread's kernel stack */       \
  47        lwz     r11, THREAD_INFO-THREAD(r10);                                \
  48        ALLOC_STACK_FRAME(r11, THREAD_SIZE);                                 \
  491 :     subi    r11, r11, INT_FRAME_SIZE; /* Allocate exception frame */     \
  50        stw     r13, _CCR(r11);         /* save various registers */         \
  51        stw     r12,GPR12(r11);                                              \
  52        stw     r9,GPR9(r11);                                                \
  53        mfspr   r13, SPRN_SPRG_RSCRATCH0;                                    \
  54        stw     r13, GPR10(r11);                                             \
  55        lwz     r12, THREAD_NORMSAVE(0)(r10);                                \
  56        stw     r12,GPR11(r11);                                              \
  57        lwz     r13, THREAD_NORMSAVE(2)(r10); /* restore r13 */              \
  58        mflr    r10;                                                         \
  59        stw     r10,_LINK(r11);                                              \
  60        mfspr   r12,SPRN_SRR0;                                               \
  61        stw     r1, GPR1(r11);                                               \
  62        mfspr   r9,SPRN_SRR1;                                                \
  63        stw     r1, 0(r11);                                                  \
  64        mr      r1, r11;                                                     \
  65        rlwinm  r9,r9,0,14,12;          /* clear MSR_WE (necessary?)       */\
  66        stw     r0,GPR0(r11);                                                \
  67        lis     r10, STACK_FRAME_REGS_MARKER@ha;/* exception frame marker */ \
  68        addi    r10, r10, STACK_FRAME_REGS_MARKER@l;                         \
  69        stw     r10, 8(r11);                                                 \
  70        SAVE_4GPRS(3, r11);                                                  \
  71        SAVE_2GPRS(7, r11)
  72
  73/* To handle the additional exception priority levels on 40x and Book-E
  74 * processors we allocate a stack per additional priority level.
  75 *
  76 * On 40x critical is the only additional level
  77 * On 44x/e500 we have critical and machine check
  78 * On e200 we have critical and debug (machine check occurs via critical)
  79 *
  80 * Additionally we reserve a SPRG for each priority level so we can free up a
  81 * GPR to use as the base for indirect access to the exception stacks.  This
  82 * is necessary since the MMU is always on, for Book-E parts, and the stacks
  83 * are offset from KERNELBASE.
  84 *
  85 * There is some space optimization to be had here if desired.  However
  86 * to allow for a common kernel with support for debug exceptions either
  87 * going to critical or their own debug level we aren't currently
  88 * providing configurations that micro-optimize space usage.
  89 */
  90
  91#define MC_STACK_BASE           mcheckirq_ctx
  92#define CRIT_STACK_BASE         critirq_ctx
  93
  94/* only on e500mc/e200 */
  95#define DBG_STACK_BASE          dbgirq_ctx
  96
  97#define EXC_LVL_FRAME_OVERHEAD  (THREAD_SIZE - INT_FRAME_SIZE - EXC_LVL_SIZE)
  98
  99#ifdef CONFIG_SMP
 100#define BOOKE_LOAD_EXC_LEVEL_STACK(level)               \
 101        mfspr   r8,SPRN_PIR;                            \
 102        slwi    r8,r8,2;                                \
 103        addis   r8,r8,level##_STACK_BASE@ha;            \
 104        lwz     r8,level##_STACK_BASE@l(r8);            \
 105        addi    r8,r8,EXC_LVL_FRAME_OVERHEAD;
 106#else
 107#define BOOKE_LOAD_EXC_LEVEL_STACK(level)               \
 108        lis     r8,level##_STACK_BASE@ha;               \
 109        lwz     r8,level##_STACK_BASE@l(r8);            \
 110        addi    r8,r8,EXC_LVL_FRAME_OVERHEAD;
 111#endif
 112
 113/*
 114 * Exception prolog for critical/machine check exceptions.  This is a
 115 * little different from the normal exception prolog above since a
 116 * critical/machine check exception can potentially occur at any point
 117 * during normal exception processing. Thus we cannot use the same SPRG
 118 * registers as the normal prolog above. Instead we use a portion of the
 119 * critical/machine check exception stack at low physical addresses.
 120 */
 121#define EXC_LEVEL_EXCEPTION_PROLOG(exc_level, intno, exc_level_srr0, exc_level_srr1) \
 122        mtspr   SPRN_SPRG_WSCRATCH_##exc_level,r8;                           \
 123        BOOKE_LOAD_EXC_LEVEL_STACK(exc_level);/* r8 points to the exc_level stack*/ \
 124        stw     r9,GPR9(r8);            /* save various registers          */\
 125        mfcr    r9;                     /* save CR in r9 for now           */\
 126        stw     r10,GPR10(r8);                                               \
 127        stw     r11,GPR11(r8);                                               \
 128        stw     r9,_CCR(r8);            /* save CR on stack                */\
 129        mfspr   r11,exc_level_srr1;     /* check whether user or kernel    */\
 130        DO_KVM  BOOKE_INTERRUPT_##intno exc_level_srr1;                      \
 131        andi.   r11,r11,MSR_PR;                                              \
 132        mfspr   r11,SPRN_SPRG_THREAD;   /* if from user, start at top of   */\
 133        lwz     r11,THREAD_INFO-THREAD(r11); /* this thread's kernel stack */\
 134        addi    r11,r11,EXC_LVL_FRAME_OVERHEAD; /* allocate stack frame    */\
 135        beq     1f;                                                          \
 136        /* COMING FROM USER MODE */                                          \
 137        stw     r9,_CCR(r11);           /* save CR                         */\
 138        lwz     r10,GPR10(r8);          /* copy regs from exception stack  */\
 139        lwz     r9,GPR9(r8);                                                 \
 140        stw     r10,GPR10(r11);                                              \
 141        lwz     r10,GPR11(r8);                                               \
 142        stw     r9,GPR9(r11);                                                \
 143        stw     r10,GPR11(r11);                                              \
 144        b       2f;                                                          \
 145        /* COMING FROM PRIV MODE */                                          \
 1461:      lwz     r9,TI_FLAGS-EXC_LVL_FRAME_OVERHEAD(r11);                     \
 147        lwz     r10,TI_PREEMPT-EXC_LVL_FRAME_OVERHEAD(r11);                  \
 148        stw     r9,TI_FLAGS-EXC_LVL_FRAME_OVERHEAD(r8);                      \
 149        stw     r10,TI_PREEMPT-EXC_LVL_FRAME_OVERHEAD(r8);                   \
 150        lwz     r9,TI_TASK-EXC_LVL_FRAME_OVERHEAD(r11);                      \
 151        stw     r9,TI_TASK-EXC_LVL_FRAME_OVERHEAD(r8);                       \
 152        mr      r11,r8;                                                      \
 1532:      mfspr   r8,SPRN_SPRG_RSCRATCH_##exc_level;                           \
 154        stw     r12,GPR12(r11);         /* save various registers          */\
 155        mflr    r10;                                                         \
 156        stw     r10,_LINK(r11);                                              \
 157        mfspr   r12,SPRN_DEAR;          /* save DEAR and ESR in the frame  */\
 158        stw     r12,_DEAR(r11);         /* since they may have had stuff   */\
 159        mfspr   r9,SPRN_ESR;            /* in them at the point where the  */\
 160        stw     r9,_ESR(r11);           /* exception was taken             */\
 161        mfspr   r12,exc_level_srr0;                                          \
 162        stw     r1,GPR1(r11);                                                \
 163        mfspr   r9,exc_level_srr1;                                           \
 164        stw     r1,0(r11);                                                   \
 165        mr      r1,r11;                                                      \
 166        rlwinm  r9,r9,0,14,12;          /* clear MSR_WE (necessary?)       */\
 167        stw     r0,GPR0(r11);                                                \
 168        SAVE_4GPRS(3, r11);                                                  \
 169        SAVE_2GPRS(7, r11)
 170
 171#define CRITICAL_EXCEPTION_PROLOG(intno) \
 172                EXC_LEVEL_EXCEPTION_PROLOG(CRIT, intno, SPRN_CSRR0, SPRN_CSRR1)
 173#define DEBUG_EXCEPTION_PROLOG \
 174                EXC_LEVEL_EXCEPTION_PROLOG(DBG, DEBUG, SPRN_DSRR0, SPRN_DSRR1)
 175#define MCHECK_EXCEPTION_PROLOG \
 176                EXC_LEVEL_EXCEPTION_PROLOG(MC, MACHINE_CHECK, \
 177                        SPRN_MCSRR0, SPRN_MCSRR1)
 178
 179/*
 180 * Guest Doorbell -- this is a bit odd in that uses GSRR0/1 despite
 181 * being delivered to the host.  This exception can only happen
 182 * inside a KVM guest -- so we just handle up to the DO_KVM rather
 183 * than try to fit this into one of the existing prolog macros.
 184 */
 185#define GUEST_DOORBELL_EXCEPTION \
 186        START_EXCEPTION(GuestDoorbell);                                      \
 187        mtspr   SPRN_SPRG_WSCRATCH0, r10;       /* save one register */      \
 188        mfspr   r10, SPRN_SPRG_THREAD;                                       \
 189        stw     r11, THREAD_NORMSAVE(0)(r10);                                \
 190        mfspr   r11, SPRN_SRR1;                                              \
 191        stw     r13, THREAD_NORMSAVE(2)(r10);                                \
 192        mfcr    r13;                    /* save CR in r13 for now          */\
 193        DO_KVM  BOOKE_INTERRUPT_GUEST_DBELL SPRN_GSRR1;                      \
 194        trap
 195
 196/*
 197 * Exception vectors.
 198 */
 199#define START_EXCEPTION(label)                                               \
 200        .align 5;                                                            \
 201label:
 202
 203#define EXCEPTION(n, intno, label, hdlr, xfer)                  \
 204        START_EXCEPTION(label);                                 \
 205        NORMAL_EXCEPTION_PROLOG(intno);                         \
 206        addi    r3,r1,STACK_FRAME_OVERHEAD;                     \
 207        xfer(n, hdlr)
 208
 209#define CRITICAL_EXCEPTION(n, intno, label, hdlr)                       \
 210        START_EXCEPTION(label);                                         \
 211        CRITICAL_EXCEPTION_PROLOG(intno);                               \
 212        addi    r3,r1,STACK_FRAME_OVERHEAD;                             \
 213        EXC_XFER_TEMPLATE(hdlr, n+2, (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), \
 214                          NOCOPY, crit_transfer_to_handler, \
 215                          ret_from_crit_exc)
 216
 217#define MCHECK_EXCEPTION(n, label, hdlr)                        \
 218        START_EXCEPTION(label);                                 \
 219        MCHECK_EXCEPTION_PROLOG;                                \
 220        mfspr   r5,SPRN_ESR;                                    \
 221        stw     r5,_ESR(r11);                                   \
 222        addi    r3,r1,STACK_FRAME_OVERHEAD;                     \
 223        EXC_XFER_TEMPLATE(hdlr, n+4, (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), \
 224                          NOCOPY, mcheck_transfer_to_handler,   \
 225                          ret_from_mcheck_exc)
 226
 227#define EXC_XFER_TEMPLATE(hdlr, trap, msr, copyee, tfer, ret)   \
 228        li      r10,trap;                                       \
 229        stw     r10,_TRAP(r11);                                 \
 230        lis     r10,msr@h;                                      \
 231        ori     r10,r10,msr@l;                                  \
 232        copyee(r10, r9);                                        \
 233        bl      tfer;                                           \
 234        .long   hdlr;                                           \
 235        .long   ret
 236
 237#define COPY_EE(d, s)           rlwimi d,s,0,16,16
 238#define NOCOPY(d, s)
 239
 240#define EXC_XFER_STD(n, hdlr)           \
 241        EXC_XFER_TEMPLATE(hdlr, n, MSR_KERNEL, NOCOPY, transfer_to_handler_full, \
 242                          ret_from_except_full)
 243
 244#define EXC_XFER_LITE(n, hdlr)          \
 245        EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL, NOCOPY, transfer_to_handler, \
 246                          ret_from_except)
 247
 248#define EXC_XFER_EE(n, hdlr)            \
 249        EXC_XFER_TEMPLATE(hdlr, n, MSR_KERNEL, COPY_EE, transfer_to_handler_full, \
 250                          ret_from_except_full)
 251
 252#define EXC_XFER_EE_LITE(n, hdlr)       \
 253        EXC_XFER_TEMPLATE(hdlr, n+1, MSR_KERNEL, COPY_EE, transfer_to_handler, \
 254                          ret_from_except)
 255
 256/* Check for a single step debug exception while in an exception
 257 * handler before state has been saved.  This is to catch the case
 258 * where an instruction that we are trying to single step causes
 259 * an exception (eg ITLB/DTLB miss) and thus the first instruction of
 260 * the exception handler generates a single step debug exception.
 261 *
 262 * If we get a debug trap on the first instruction of an exception handler,
 263 * we reset the MSR_DE in the _exception handler's_ MSR (the debug trap is
 264 * a critical exception, so we are using SPRN_CSRR1 to manipulate the MSR).
 265 * The exception handler was handling a non-critical interrupt, so it will
 266 * save (and later restore) the MSR via SPRN_CSRR1, which will still have
 267 * the MSR_DE bit set.
 268 */
 269#define DEBUG_DEBUG_EXCEPTION                                                 \
 270        START_EXCEPTION(DebugDebug);                                          \
 271        DEBUG_EXCEPTION_PROLOG;                                               \
 272                                                                              \
 273        /*                                                                    \
 274         * If there is a single step or branch-taken exception in an          \
 275         * exception entry sequence, it was probably meant to apply to        \
 276         * the code where the exception occurred (since exception entry       \
 277         * doesn't turn off DE automatically).  We simulate the effect        \
 278         * of turning off DE on entry to an exception handler by turning      \
 279         * off DE in the DSRR1 value and clearing the debug status.           \
 280         */                                                                   \
 281        mfspr   r10,SPRN_DBSR;          /* check single-step/branch taken */  \
 282        andis.  r10,r10,(DBSR_IC|DBSR_BT)@h;                                  \
 283        beq+    2f;                                                           \
 284                                                                              \
 285        lis     r10,interrupt_base@h;   /* check if exception in vectors */   \
 286        ori     r10,r10,interrupt_base@l;                                     \
 287        cmplw   r12,r10;                                                      \
 288        blt+    2f;                     /* addr below exception vectors */    \
 289                                                                              \
 290        lis     r10,interrupt_end@h;                                          \
 291        ori     r10,r10,interrupt_end@l;                                      \
 292        cmplw   r12,r10;                                                      \
 293        bgt+    2f;                     /* addr above exception vectors */    \
 294                                                                              \
 295        /* here it looks like we got an inappropriate debug exception. */     \
 2961:      rlwinm  r9,r9,0,~MSR_DE;        /* clear DE in the CDRR1 value */     \
 297        lis     r10,(DBSR_IC|DBSR_BT)@h;        /* clear the IC event */      \
 298        mtspr   SPRN_DBSR,r10;                                                \
 299        /* restore state and get out */                                       \
 300        lwz     r10,_CCR(r11);                                                \
 301        lwz     r0,GPR0(r11);                                                 \
 302        lwz     r1,GPR1(r11);                                                 \
 303        mtcrf   0x80,r10;                                                     \
 304        mtspr   SPRN_DSRR0,r12;                                               \
 305        mtspr   SPRN_DSRR1,r9;                                                \
 306        lwz     r9,GPR9(r11);                                                 \
 307        lwz     r12,GPR12(r11);                                               \
 308        mtspr   SPRN_SPRG_WSCRATCH_DBG,r8;                                    \
 309        BOOKE_LOAD_EXC_LEVEL_STACK(DBG); /* r8 points to the debug stack */ \
 310        lwz     r10,GPR10(r8);                                                \
 311        lwz     r11,GPR11(r8);                                                \
 312        mfspr   r8,SPRN_SPRG_RSCRATCH_DBG;                                    \
 313                                                                              \
 314        PPC_RFDI;                                                             \
 315        b       .;                                                            \
 316                                                                              \
 317        /* continue normal handling for a debug exception... */               \
 3182:      mfspr   r4,SPRN_DBSR;                                                 \
 319        addi    r3,r1,STACK_FRAME_OVERHEAD;                                   \
 320        EXC_XFER_TEMPLATE(DebugException, 0x2008, (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), NOCOPY, debug_transfer_to_handler, ret_from_debug_exc)
 321
 322#define DEBUG_CRIT_EXCEPTION                                                  \
 323        START_EXCEPTION(DebugCrit);                                           \
 324        CRITICAL_EXCEPTION_PROLOG(DEBUG);                                     \
 325                                                                              \
 326        /*                                                                    \
 327         * If there is a single step or branch-taken exception in an          \
 328         * exception entry sequence, it was probably meant to apply to        \
 329         * the code where the exception occurred (since exception entry       \
 330         * doesn't turn off DE automatically).  We simulate the effect        \
 331         * of turning off DE on entry to an exception handler by turning      \
 332         * off DE in the CSRR1 value and clearing the debug status.           \
 333         */                                                                   \
 334        mfspr   r10,SPRN_DBSR;          /* check single-step/branch taken */  \
 335        andis.  r10,r10,(DBSR_IC|DBSR_BT)@h;                                  \
 336        beq+    2f;                                                           \
 337                                                                              \
 338        lis     r10,interrupt_base@h;   /* check if exception in vectors */   \
 339        ori     r10,r10,interrupt_base@l;                                     \
 340        cmplw   r12,r10;                                                      \
 341        blt+    2f;                     /* addr below exception vectors */    \
 342                                                                              \
 343        lis     r10,interrupt_end@h;                                          \
 344        ori     r10,r10,interrupt_end@l;                                      \
 345        cmplw   r12,r10;                                                      \
 346        bgt+    2f;                     /* addr above exception vectors */    \
 347                                                                              \
 348        /* here it looks like we got an inappropriate debug exception. */     \
 3491:      rlwinm  r9,r9,0,~MSR_DE;        /* clear DE in the CSRR1 value */     \
 350        lis     r10,(DBSR_IC|DBSR_BT)@h;        /* clear the IC event */      \
 351        mtspr   SPRN_DBSR,r10;                                                \
 352        /* restore state and get out */                                       \
 353        lwz     r10,_CCR(r11);                                                \
 354        lwz     r0,GPR0(r11);                                                 \
 355        lwz     r1,GPR1(r11);                                                 \
 356        mtcrf   0x80,r10;                                                     \
 357        mtspr   SPRN_CSRR0,r12;                                               \
 358        mtspr   SPRN_CSRR1,r9;                                                \
 359        lwz     r9,GPR9(r11);                                                 \
 360        lwz     r12,GPR12(r11);                                               \
 361        mtspr   SPRN_SPRG_WSCRATCH_CRIT,r8;                                   \
 362        BOOKE_LOAD_EXC_LEVEL_STACK(CRIT); /* r8 points to the debug stack */  \
 363        lwz     r10,GPR10(r8);                                                \
 364        lwz     r11,GPR11(r8);                                                \
 365        mfspr   r8,SPRN_SPRG_RSCRATCH_CRIT;                                   \
 366                                                                              \
 367        rfci;                                                                 \
 368        b       .;                                                            \
 369                                                                              \
 370        /* continue normal handling for a critical exception... */            \
 3712:      mfspr   r4,SPRN_DBSR;                                                 \
 372        addi    r3,r1,STACK_FRAME_OVERHEAD;                                   \
 373        EXC_XFER_TEMPLATE(DebugException, 0x2002, (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), NOCOPY, crit_transfer_to_handler, ret_from_crit_exc)
 374
 375#define DATA_STORAGE_EXCEPTION                                                \
 376        START_EXCEPTION(DataStorage)                                          \
 377        NORMAL_EXCEPTION_PROLOG(DATA_STORAGE);                \
 378        mfspr   r5,SPRN_ESR;            /* Grab the ESR and save it */        \
 379        stw     r5,_ESR(r11);                                                 \
 380        mfspr   r4,SPRN_DEAR;           /* Grab the DEAR */                   \
 381        EXC_XFER_LITE(0x0300, handle_page_fault)
 382
 383#define INSTRUCTION_STORAGE_EXCEPTION                                         \
 384        START_EXCEPTION(InstructionStorage)                                   \
 385        NORMAL_EXCEPTION_PROLOG(INST_STORAGE);                \
 386        mfspr   r5,SPRN_ESR;            /* Grab the ESR and save it */        \
 387        stw     r5,_ESR(r11);                                                 \
 388        mr      r4,r12;                 /* Pass SRR0 as arg2 */               \
 389        li      r5,0;                   /* Pass zero as arg3 */               \
 390        EXC_XFER_LITE(0x0400, handle_page_fault)
 391
 392#define ALIGNMENT_EXCEPTION                                                   \
 393        START_EXCEPTION(Alignment)                                            \
 394        NORMAL_EXCEPTION_PROLOG(ALIGNMENT);                   \
 395        mfspr   r4,SPRN_DEAR;           /* Grab the DEAR and save it */       \
 396        stw     r4,_DEAR(r11);                                                \
 397        addi    r3,r1,STACK_FRAME_OVERHEAD;                                   \
 398        EXC_XFER_EE(0x0600, alignment_exception)
 399
 400#define PROGRAM_EXCEPTION                                                     \
 401        START_EXCEPTION(Program)                                              \
 402        NORMAL_EXCEPTION_PROLOG(PROGRAM);                     \
 403        mfspr   r4,SPRN_ESR;            /* Grab the ESR and save it */        \
 404        stw     r4,_ESR(r11);                                                 \
 405        addi    r3,r1,STACK_FRAME_OVERHEAD;                                   \
 406        EXC_XFER_STD(0x0700, program_check_exception)
 407
 408#define DECREMENTER_EXCEPTION                                                 \
 409        START_EXCEPTION(Decrementer)                                          \
 410        NORMAL_EXCEPTION_PROLOG(DECREMENTER);                 \
 411        lis     r0,TSR_DIS@h;           /* Setup the DEC interrupt mask */    \
 412        mtspr   SPRN_TSR,r0;            /* Clear the DEC interrupt */         \
 413        addi    r3,r1,STACK_FRAME_OVERHEAD;                                   \
 414        EXC_XFER_LITE(0x0900, timer_interrupt)
 415
 416#define FP_UNAVAILABLE_EXCEPTION                                              \
 417        START_EXCEPTION(FloatingPointUnavailable)                             \
 418        NORMAL_EXCEPTION_PROLOG(FP_UNAVAIL);                  \
 419        beq     1f;                                                           \
 420        bl      load_up_fpu;            /* if from user, just load it up */   \
 421        b       fast_exception_return;                                        \
 4221:      addi    r3,r1,STACK_FRAME_OVERHEAD;                                   \
 423        EXC_XFER_EE_LITE(0x800, kernel_fp_unavailable_exception)
 424
 425#ifndef __ASSEMBLY__
 426struct exception_regs {
 427        unsigned long mas0;
 428        unsigned long mas1;
 429        unsigned long mas2;
 430        unsigned long mas3;
 431        unsigned long mas6;
 432        unsigned long mas7;
 433        unsigned long srr0;
 434        unsigned long srr1;
 435        unsigned long csrr0;
 436        unsigned long csrr1;
 437        unsigned long dsrr0;
 438        unsigned long dsrr1;
 439        unsigned long saved_ksp_limit;
 440};
 441
 442/* ensure this structure is always sized to a multiple of the stack alignment */
 443#define STACK_EXC_LVL_FRAME_SIZE        _ALIGN_UP(sizeof (struct exception_regs), 16)
 444
 445#endif /* __ASSEMBLY__ */
 446#endif /* __HEAD_BOOKE_H__ */
 447