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 #ifdef __ASSEMBLY__ 10 11 /* 12 * Macros used for common Book-e exception handling 13 */ 14 15 #define SET_IVOR(vector_number, vector_label) \ 16 li r26,vector_label@l; \ 17 mtspr SPRN_IVOR##vector_number,r26; \ 18 sync 19 20 #if (THREAD_SHIFT < 15) 21 #define ALLOC_STACK_FRAME(reg, val) \ 22 addi reg,reg,val 23 #else 24 #define ALLOC_STACK_FRAME(reg, val) \ 25 addis reg,reg,val@ha; \ 26 addi reg,reg,val@l 27 #endif 28 29 /* 30 * Macro used to get to thread save registers. 31 * Note that entries 0-3 are used for the prolog code, and the remaining 32 * entries are available for specific exception use in the event a handler 33 * requires more than 4 scratch registers. 34 */ 35 #define THREAD_NORMSAVE(offset) (THREAD_NORMSAVES + (offset * 4)) 36 37 #ifdef CONFIG_PPC_E500 38 #define BOOKE_CLEAR_BTB(reg) \ 39 START_BTB_FLUSH_SECTION \ 40 BTB_FLUSH(reg) \ 41 END_BTB_FLUSH_SECTION 42 #else 43 #define BOOKE_CLEAR_BTB(reg) 44 #endif 45 46 47 #define NORMAL_EXCEPTION_PROLOG(trapno, intno) \ 48 mtspr SPRN_SPRG_WSCRATCH0, r10; /* save one register */ \ 49 mfspr r10, SPRN_SPRG_THREAD; \ 50 stw r11, THREAD_NORMSAVE(0)(r10); \ 51 stw r13, THREAD_NORMSAVE(2)(r10); \ 52 mfcr r13; /* save CR in r13 for now */\ 53 mfspr r11, SPRN_SRR1; \ 54 DO_KVM BOOKE_INTERRUPT_##intno SPRN_SRR1; \ 55 andi. r11, r11, MSR_PR; /* check whether user or kernel */\ 56 LOAD_REG_IMMEDIATE(r11, MSR_KERNEL); \ 57 mtmsr r11; \ 58 mr r11, r1; \ 59 beq 1f; \ 60 BOOKE_CLEAR_BTB(r11) \ 61 /* if from user, start at top of this thread's kernel stack */ \ 62 lwz r11, TASK_STACK - THREAD(r10); \ 63 ALLOC_STACK_FRAME(r11, THREAD_SIZE); \ 64 1 : subi r11, r11, INT_FRAME_SIZE; /* Allocate exception frame */ \ 65 stw r13, _CCR(r11); /* save various registers */ \ 66 stw r12,GPR12(r11); \ 67 stw r9,GPR9(r11); \ 68 mfspr r13, SPRN_SPRG_RSCRATCH0; \ 69 stw r13, GPR10(r11); \ 70 lwz r12, THREAD_NORMSAVE(0)(r10); \ 71 stw r12,GPR11(r11); \ 72 lwz r13, THREAD_NORMSAVE(2)(r10); /* restore r13 */ \ 73 mflr r10; \ 74 stw r10,_LINK(r11); \ 75 mfspr r12,SPRN_SRR0; \ 76 stw r1, GPR1(r11); \ 77 mfspr r9,SPRN_SRR1; \ 78 stw r1, 0(r11); \ 79 mr r1, r11; \ 80 rlwinm r9,r9,0,14,12; /* clear MSR_WE (necessary?) */\ 81 COMMON_EXCEPTION_PROLOG_END trapno 82 83 .macro COMMON_EXCEPTION_PROLOG_END trapno 84 stw r0,GPR0(r1) 85 lis r10, STACK_FRAME_REGS_MARKER@ha /* exception frame marker */ 86 addi r10, r10, STACK_FRAME_REGS_MARKER@l 87 stw r10, 8(r1) 88 li r10, \trapno 89 stw r10,_TRAP(r1) 90 SAVE_GPRS(3, 8, r1) 91 SAVE_NVGPRS(r1) 92 stw r2,GPR2(r1) 93 stw r12,_NIP(r1) 94 stw r9,_MSR(r1) 95 mfctr r10 96 mfspr r2,SPRN_SPRG_THREAD 97 stw r10,_CTR(r1) 98 tovirt(r2, r2) 99 mfspr r10,SPRN_XER 100 addi r2, r2, -THREAD 101 stw r10,_XER(r1) 102 addi r3,r1,STACK_FRAME_OVERHEAD 103 .endm 104 105 .macro prepare_transfer_to_handler 106 #ifdef CONFIG_PPC_E500 107 andi. r12,r9,MSR_PR 108 bne 777f 109 bl prepare_transfer_to_handler 110 777: 111 #endif 112 .endm 113 114 .macro SYSCALL_ENTRY trapno intno srr1 115 mfspr r10, SPRN_SPRG_THREAD 116 #ifdef CONFIG_KVM_BOOKE_HV 117 BEGIN_FTR_SECTION 118 mtspr SPRN_SPRG_WSCRATCH0, r10 119 stw r11, THREAD_NORMSAVE(0)(r10) 120 stw r13, THREAD_NORMSAVE(2)(r10) 121 mfcr r13 /* save CR in r13 for now */ 122 mfspr r11, SPRN_SRR1 123 mtocrf 0x80, r11 /* check MSR[GS] without clobbering reg */ 124 bf 3, 1975f 125 b kvmppc_handler_\intno\()_\srr1 126 1975: 127 mr r12, r13 128 lwz r13, THREAD_NORMSAVE(2)(r10) 129 FTR_SECTION_ELSE 130 mfcr r12 131 ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV) 132 #else 133 mfcr r12 134 #endif 135 mfspr r9, SPRN_SRR1 136 BOOKE_CLEAR_BTB(r11) 137 mr r11, r1 138 lwz r1, TASK_STACK - THREAD(r10) 139 rlwinm r12,r12,0,4,2 /* Clear SO bit in CR */ 140 ALLOC_STACK_FRAME(r1, THREAD_SIZE - INT_FRAME_SIZE) 141 stw r12, _CCR(r1) 142 mfspr r12,SPRN_SRR0 143 stw r12,_NIP(r1) 144 b transfer_to_syscall /* jump to handler */ 145 .endm 146 147 /* To handle the additional exception priority levels on 40x and Book-E 148 * processors we allocate a stack per additional priority level. 149 * 150 * On 40x critical is the only additional level 151 * On 44x/e500 we have critical and machine check 152 * 153 * Additionally we reserve a SPRG for each priority level so we can free up a 154 * GPR to use as the base for indirect access to the exception stacks. This 155 * is necessary since the MMU is always on, for Book-E parts, and the stacks 156 * are offset from KERNELBASE. 157 * 158 * There is some space optimization to be had here if desired. However 159 * to allow for a common kernel with support for debug exceptions either 160 * going to critical or their own debug level we aren't currently 161 * providing configurations that micro-optimize space usage. 162 */ 163 164 #define MC_STACK_BASE mcheckirq_ctx 165 #define CRIT_STACK_BASE critirq_ctx 166 167 /* only on e500mc */ 168 #define DBG_STACK_BASE dbgirq_ctx 169 170 #ifdef CONFIG_SMP 171 #define BOOKE_LOAD_EXC_LEVEL_STACK(level) \ 172 mfspr r8,SPRN_PIR; \ 173 slwi r8,r8,2; \ 174 addis r8,r8,level##_STACK_BASE@ha; \ 175 lwz r8,level##_STACK_BASE@l(r8); \ 176 addi r8,r8,THREAD_SIZE - INT_FRAME_SIZE; 177 #else 178 #define BOOKE_LOAD_EXC_LEVEL_STACK(level) \ 179 lis r8,level##_STACK_BASE@ha; \ 180 lwz r8,level##_STACK_BASE@l(r8); \ 181 addi r8,r8,THREAD_SIZE - INT_FRAME_SIZE; 182 #endif 183 184 /* 185 * Exception prolog for critical/machine check exceptions. This is a 186 * little different from the normal exception prolog above since a 187 * critical/machine check exception can potentially occur at any point 188 * during normal exception processing. Thus we cannot use the same SPRG 189 * registers as the normal prolog above. Instead we use a portion of the 190 * critical/machine check exception stack at low physical addresses. 191 */ 192 #define EXC_LEVEL_EXCEPTION_PROLOG(exc_level, trapno, intno, exc_level_srr0, exc_level_srr1) \ 193 mtspr SPRN_SPRG_WSCRATCH_##exc_level,r8; \ 194 BOOKE_LOAD_EXC_LEVEL_STACK(exc_level);/* r8 points to the exc_level stack*/ \ 195 stw r9,GPR9(r8); /* save various registers */\ 196 mfcr r9; /* save CR in r9 for now */\ 197 stw r10,GPR10(r8); \ 198 stw r11,GPR11(r8); \ 199 stw r9,_CCR(r8); /* save CR on stack */\ 200 mfspr r11,exc_level_srr1; /* check whether user or kernel */\ 201 DO_KVM BOOKE_INTERRUPT_##intno exc_level_srr1; \ 202 BOOKE_CLEAR_BTB(r10) \ 203 andi. r11,r11,MSR_PR; \ 204 LOAD_REG_IMMEDIATE(r11, MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)); \ 205 mtmsr r11; \ 206 mfspr r11,SPRN_SPRG_THREAD; /* if from user, start at top of */\ 207 lwz r11, TASK_STACK - THREAD(r11); /* this thread's kernel stack */\ 208 addi r11,r11,THREAD_SIZE - INT_FRAME_SIZE; /* allocate stack frame */\ 209 beq 1f; \ 210 /* COMING FROM USER MODE */ \ 211 stw r9,_CCR(r11); /* save CR */\ 212 lwz r10,GPR10(r8); /* copy regs from exception stack */\ 213 lwz r9,GPR9(r8); \ 214 stw r10,GPR10(r11); \ 215 lwz r10,GPR11(r8); \ 216 stw r9,GPR9(r11); \ 217 stw r10,GPR11(r11); \ 218 b 2f; \ 219 /* COMING FROM PRIV MODE */ \ 220 1: mr r11, r8; \ 221 2: mfspr r8,SPRN_SPRG_RSCRATCH_##exc_level; \ 222 stw r12,GPR12(r11); /* save various registers */\ 223 mflr r10; \ 224 stw r10,_LINK(r11); \ 225 mfspr r12,SPRN_DEAR; /* save DEAR and ESR in the frame */\ 226 stw r12,_DEAR(r11); /* since they may have had stuff */\ 227 mfspr r9,SPRN_ESR; /* in them at the point where the */\ 228 stw r9,_ESR(r11); /* exception was taken */\ 229 mfspr r12,exc_level_srr0; \ 230 stw r1,GPR1(r11); \ 231 mfspr r9,exc_level_srr1; \ 232 stw r1,0(r11); \ 233 mr r1,r11; \ 234 rlwinm r9,r9,0,14,12; /* clear MSR_WE (necessary?) */\ 235 COMMON_EXCEPTION_PROLOG_END trapno 236 237 #define SAVE_xSRR(xSRR) \ 238 mfspr r0,SPRN_##xSRR##0; \ 239 stw r0,_##xSRR##0(r1); \ 240 mfspr r0,SPRN_##xSRR##1; \ 241 stw r0,_##xSRR##1(r1) 242 243 244 .macro SAVE_MMU_REGS 245 #ifdef CONFIG_PPC_E500 246 mfspr r0,SPRN_MAS0 247 stw r0,MAS0(r1) 248 mfspr r0,SPRN_MAS1 249 stw r0,MAS1(r1) 250 mfspr r0,SPRN_MAS2 251 stw r0,MAS2(r1) 252 mfspr r0,SPRN_MAS3 253 stw r0,MAS3(r1) 254 mfspr r0,SPRN_MAS6 255 stw r0,MAS6(r1) 256 #ifdef CONFIG_PHYS_64BIT 257 mfspr r0,SPRN_MAS7 258 stw r0,MAS7(r1) 259 #endif /* CONFIG_PHYS_64BIT */ 260 #endif /* CONFIG_PPC_E500 */ 261 #ifdef CONFIG_44x 262 mfspr r0,SPRN_MMUCR 263 stw r0,MMUCR(r1) 264 #endif 265 .endm 266 267 #define CRITICAL_EXCEPTION_PROLOG(trapno, intno) \ 268 EXC_LEVEL_EXCEPTION_PROLOG(CRIT, trapno+2, intno, SPRN_CSRR0, SPRN_CSRR1) 269 #define DEBUG_EXCEPTION_PROLOG(trapno) \ 270 EXC_LEVEL_EXCEPTION_PROLOG(DBG, trapno+8, DEBUG, SPRN_DSRR0, SPRN_DSRR1) 271 #define MCHECK_EXCEPTION_PROLOG(trapno) \ 272 EXC_LEVEL_EXCEPTION_PROLOG(MC, trapno+4, MACHINE_CHECK, \ 273 SPRN_MCSRR0, SPRN_MCSRR1) 274 275 /* 276 * Guest Doorbell -- this is a bit odd in that uses GSRR0/1 despite 277 * being delivered to the host. This exception can only happen 278 * inside a KVM guest -- so we just handle up to the DO_KVM rather 279 * than try to fit this into one of the existing prolog macros. 280 */ 281 #define GUEST_DOORBELL_EXCEPTION \ 282 START_EXCEPTION(GuestDoorbell); \ 283 mtspr SPRN_SPRG_WSCRATCH0, r10; /* save one register */ \ 284 mfspr r10, SPRN_SPRG_THREAD; \ 285 stw r11, THREAD_NORMSAVE(0)(r10); \ 286 mfspr r11, SPRN_SRR1; \ 287 stw r13, THREAD_NORMSAVE(2)(r10); \ 288 mfcr r13; /* save CR in r13 for now */\ 289 DO_KVM BOOKE_INTERRUPT_GUEST_DBELL SPRN_GSRR1; \ 290 trap 291 292 /* 293 * Exception vectors. 294 */ 295 #define START_EXCEPTION(label) \ 296 .align 5; \ 297 label: 298 299 #define EXCEPTION(n, intno, label, hdlr) \ 300 START_EXCEPTION(label); \ 301 NORMAL_EXCEPTION_PROLOG(n, intno); \ 302 prepare_transfer_to_handler; \ 303 bl hdlr; \ 304 b interrupt_return 305 306 #define CRITICAL_EXCEPTION(n, intno, label, hdlr) \ 307 START_EXCEPTION(label); \ 308 CRITICAL_EXCEPTION_PROLOG(n, intno); \ 309 SAVE_MMU_REGS; \ 310 SAVE_xSRR(SRR); \ 311 prepare_transfer_to_handler; \ 312 bl hdlr; \ 313 b ret_from_crit_exc 314 315 #define MCHECK_EXCEPTION(n, label, hdlr) \ 316 START_EXCEPTION(label); \ 317 MCHECK_EXCEPTION_PROLOG(n); \ 318 mfspr r5,SPRN_ESR; \ 319 stw r5,_ESR(r11); \ 320 SAVE_xSRR(DSRR); \ 321 SAVE_xSRR(CSRR); \ 322 SAVE_MMU_REGS; \ 323 SAVE_xSRR(SRR); \ 324 prepare_transfer_to_handler; \ 325 bl hdlr; \ 326 b ret_from_mcheck_exc 327 328 /* Check for a single step debug exception while in an exception 329 * handler before state has been saved. This is to catch the case 330 * where an instruction that we are trying to single step causes 331 * an exception (eg ITLB/DTLB miss) and thus the first instruction of 332 * the exception handler generates a single step debug exception. 333 * 334 * If we get a debug trap on the first instruction of an exception handler, 335 * we reset the MSR_DE in the _exception handler's_ MSR (the debug trap is 336 * a critical exception, so we are using SPRN_CSRR1 to manipulate the MSR). 337 * The exception handler was handling a non-critical interrupt, so it will 338 * save (and later restore) the MSR via SPRN_CSRR1, which will still have 339 * the MSR_DE bit set. 340 */ 341 #define DEBUG_DEBUG_EXCEPTION \ 342 START_EXCEPTION(DebugDebug); \ 343 DEBUG_EXCEPTION_PROLOG(2000); \ 344 \ 345 /* \ 346 * If there is a single step or branch-taken exception in an \ 347 * exception entry sequence, it was probably meant to apply to \ 348 * the code where the exception occurred (since exception entry \ 349 * doesn't turn off DE automatically). We simulate the effect \ 350 * of turning off DE on entry to an exception handler by turning \ 351 * off DE in the DSRR1 value and clearing the debug status. \ 352 */ \ 353 mfspr r10,SPRN_DBSR; /* check single-step/branch taken */ \ 354 andis. r10,r10,(DBSR_IC|DBSR_BT)@h; \ 355 beq+ 2f; \ 356 \ 357 lis r10,interrupt_base@h; /* check if exception in vectors */ \ 358 ori r10,r10,interrupt_base@l; \ 359 cmplw r12,r10; \ 360 blt+ 2f; /* addr below exception vectors */ \ 361 \ 362 lis r10,interrupt_end@h; \ 363 ori r10,r10,interrupt_end@l; \ 364 cmplw r12,r10; \ 365 bgt+ 2f; /* addr above exception vectors */ \ 366 \ 367 /* here it looks like we got an inappropriate debug exception. */ \ 368 1: rlwinm r9,r9,0,~MSR_DE; /* clear DE in the CDRR1 value */ \ 369 lis r10,(DBSR_IC|DBSR_BT)@h; /* clear the IC event */ \ 370 mtspr SPRN_DBSR,r10; \ 371 /* restore state and get out */ \ 372 lwz r10,_CCR(r11); \ 373 lwz r0,GPR0(r11); \ 374 lwz r1,GPR1(r11); \ 375 mtcrf 0x80,r10; \ 376 mtspr SPRN_DSRR0,r12; \ 377 mtspr SPRN_DSRR1,r9; \ 378 lwz r9,GPR9(r11); \ 379 lwz r12,GPR12(r11); \ 380 mtspr SPRN_SPRG_WSCRATCH_DBG,r8; \ 381 BOOKE_LOAD_EXC_LEVEL_STACK(DBG); /* r8 points to the debug stack */ \ 382 lwz r10,GPR10(r8); \ 383 lwz r11,GPR11(r8); \ 384 mfspr r8,SPRN_SPRG_RSCRATCH_DBG; \ 385 \ 386 PPC_RFDI; \ 387 b .; \ 388 \ 389 /* continue normal handling for a debug exception... */ \ 390 2: mfspr r4,SPRN_DBSR; \ 391 stw r4,_ESR(r11); /* DebugException takes DBSR in _ESR */\ 392 SAVE_xSRR(CSRR); \ 393 SAVE_MMU_REGS; \ 394 SAVE_xSRR(SRR); \ 395 prepare_transfer_to_handler; \ 396 bl DebugException; \ 397 b ret_from_debug_exc 398 399 #define DEBUG_CRIT_EXCEPTION \ 400 START_EXCEPTION(DebugCrit); \ 401 CRITICAL_EXCEPTION_PROLOG(2000,DEBUG); \ 402 \ 403 /* \ 404 * If there is a single step or branch-taken exception in an \ 405 * exception entry sequence, it was probably meant to apply to \ 406 * the code where the exception occurred (since exception entry \ 407 * doesn't turn off DE automatically). We simulate the effect \ 408 * of turning off DE on entry to an exception handler by turning \ 409 * off DE in the CSRR1 value and clearing the debug status. \ 410 */ \ 411 mfspr r10,SPRN_DBSR; /* check single-step/branch taken */ \ 412 andis. r10,r10,(DBSR_IC|DBSR_BT)@h; \ 413 beq+ 2f; \ 414 \ 415 lis r10,interrupt_base@h; /* check if exception in vectors */ \ 416 ori r10,r10,interrupt_base@l; \ 417 cmplw r12,r10; \ 418 blt+ 2f; /* addr below exception vectors */ \ 419 \ 420 lis r10,interrupt_end@h; \ 421 ori r10,r10,interrupt_end@l; \ 422 cmplw r12,r10; \ 423 bgt+ 2f; /* addr above exception vectors */ \ 424 \ 425 /* here it looks like we got an inappropriate debug exception. */ \ 426 1: rlwinm r9,r9,0,~MSR_DE; /* clear DE in the CSRR1 value */ \ 427 lis r10,(DBSR_IC|DBSR_BT)@h; /* clear the IC event */ \ 428 mtspr SPRN_DBSR,r10; \ 429 /* restore state and get out */ \ 430 lwz r10,_CCR(r11); \ 431 lwz r0,GPR0(r11); \ 432 lwz r1,GPR1(r11); \ 433 mtcrf 0x80,r10; \ 434 mtspr SPRN_CSRR0,r12; \ 435 mtspr SPRN_CSRR1,r9; \ 436 lwz r9,GPR9(r11); \ 437 lwz r12,GPR12(r11); \ 438 mtspr SPRN_SPRG_WSCRATCH_CRIT,r8; \ 439 BOOKE_LOAD_EXC_LEVEL_STACK(CRIT); /* r8 points to the debug stack */ \ 440 lwz r10,GPR10(r8); \ 441 lwz r11,GPR11(r8); \ 442 mfspr r8,SPRN_SPRG_RSCRATCH_CRIT; \ 443 \ 444 rfci; \ 445 b .; \ 446 \ 447 /* continue normal handling for a critical exception... */ \ 448 2: mfspr r4,SPRN_DBSR; \ 449 stw r4,_ESR(r11); /* DebugException takes DBSR in _ESR */\ 450 SAVE_MMU_REGS; \ 451 SAVE_xSRR(SRR); \ 452 prepare_transfer_to_handler; \ 453 bl DebugException; \ 454 b ret_from_crit_exc 455 456 #define DATA_STORAGE_EXCEPTION \ 457 START_EXCEPTION(DataStorage) \ 458 NORMAL_EXCEPTION_PROLOG(0x300, DATA_STORAGE); \ 459 mfspr r5,SPRN_ESR; /* Grab the ESR and save it */ \ 460 stw r5,_ESR(r11); \ 461 mfspr r4,SPRN_DEAR; /* Grab the DEAR */ \ 462 stw r4, _DEAR(r11); \ 463 prepare_transfer_to_handler; \ 464 bl do_page_fault; \ 465 b interrupt_return 466 467 /* 468 * Instruction TLB Error interrupt handlers may call InstructionStorage 469 * directly without clearing ESR, so the ESR at this point may be left over 470 * from a prior interrupt. 471 * 472 * In any case, do_page_fault for BOOK3E does not use ESR and always expects 473 * dsisr to be 0. ESR_DST from a prior store in particular would confuse fault 474 * handling. 475 */ 476 #define INSTRUCTION_STORAGE_EXCEPTION \ 477 START_EXCEPTION(InstructionStorage) \ 478 NORMAL_EXCEPTION_PROLOG(0x400, INST_STORAGE); \ 479 li r5,0; /* Store 0 in regs->esr (dsisr) */ \ 480 stw r5,_ESR(r11); \ 481 stw r12, _DEAR(r11); /* Set regs->dear (dar) to SRR0 */ \ 482 prepare_transfer_to_handler; \ 483 bl do_page_fault; \ 484 b interrupt_return 485 486 #define ALIGNMENT_EXCEPTION \ 487 START_EXCEPTION(Alignment) \ 488 NORMAL_EXCEPTION_PROLOG(0x600, ALIGNMENT); \ 489 mfspr r4,SPRN_DEAR; /* Grab the DEAR and save it */ \ 490 stw r4,_DEAR(r11); \ 491 prepare_transfer_to_handler; \ 492 bl alignment_exception; \ 493 REST_NVGPRS(r1); \ 494 b interrupt_return 495 496 #define PROGRAM_EXCEPTION \ 497 START_EXCEPTION(Program) \ 498 NORMAL_EXCEPTION_PROLOG(0x700, PROGRAM); \ 499 mfspr r4,SPRN_ESR; /* Grab the ESR and save it */ \ 500 stw r4,_ESR(r11); \ 501 prepare_transfer_to_handler; \ 502 bl program_check_exception; \ 503 REST_NVGPRS(r1); \ 504 b interrupt_return 505 506 #define DECREMENTER_EXCEPTION \ 507 START_EXCEPTION(Decrementer) \ 508 NORMAL_EXCEPTION_PROLOG(0x900, DECREMENTER); \ 509 lis r0,TSR_DIS@h; /* Setup the DEC interrupt mask */ \ 510 mtspr SPRN_TSR,r0; /* Clear the DEC interrupt */ \ 511 prepare_transfer_to_handler; \ 512 bl timer_interrupt; \ 513 b interrupt_return 514 515 #define FP_UNAVAILABLE_EXCEPTION \ 516 START_EXCEPTION(FloatingPointUnavailable) \ 517 NORMAL_EXCEPTION_PROLOG(0x800, FP_UNAVAIL); \ 518 beq 1f; \ 519 bl load_up_fpu; /* if from user, just load it up */ \ 520 b fast_exception_return; \ 521 1: prepare_transfer_to_handler; \ 522 bl kernel_fp_unavailable_exception; \ 523 b interrupt_return 524 525 #endif /* __ASSEMBLY__ */ 526 #endif /* __HEAD_BOOKE_H__ */ 527