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1/*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * Copyright (C) 1994 - 2000, 2001, 2003 Ralf Baechle
7 * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
8 * Copyright (C) 2002, 2007 Maciej W. Rozycki
9 * Copyright (C) 2001, 2012 MIPS Technologies, Inc. All rights reserved.
10 */
11#include <linux/init.h>
12
13#include <asm/asm.h>
14#include <asm/asmmacro.h>
15#include <asm/cacheops.h>
16#include <asm/irqflags.h>
17#include <asm/regdef.h>
18#include <asm/fpregdef.h>
19#include <asm/mipsregs.h>
20#include <asm/stackframe.h>
21#include <asm/war.h>
22#include <asm/thread_info.h>
23
24 __INIT
25
26/*
27 * General exception vector for all other CPUs.
28 *
29 * Be careful when changing this, it has to be at most 128 bytes
30 * to fit into space reserved for the exception handler.
31 */
32NESTED(except_vec3_generic, 0, sp)
33 .set push
34 .set noat
35 mfc0 k1, CP0_CAUSE
36 andi k1, k1, 0x7c
37#ifdef CONFIG_64BIT
38 dsll k1, k1, 1
39#endif
40 PTR_L k0, exception_handlers(k1)
41 jr k0
42 .set pop
43 END(except_vec3_generic)
44
45/*
46 * General exception handler for CPUs with virtual coherency exception.
47 *
48 * Be careful when changing this, it has to be at most 256 (as a special
49 * exception) bytes to fit into space reserved for the exception handler.
50 */
51NESTED(except_vec3_r4000, 0, sp)
52 .set push
53 .set arch=r4000
54 .set noat
55 mfc0 k1, CP0_CAUSE
56 li k0, 31<<2
57 andi k1, k1, 0x7c
58 .set push
59 .set noreorder
60 .set nomacro
61 beq k1, k0, handle_vced
62 li k0, 14<<2
63 beq k1, k0, handle_vcei
64#ifdef CONFIG_64BIT
65 dsll k1, k1, 1
66#endif
67 .set pop
68 PTR_L k0, exception_handlers(k1)
69 jr k0
70
71 /*
72 * Big shit, we now may have two dirty primary cache lines for the same
73 * physical address. We can safely invalidate the line pointed to by
74 * c0_badvaddr because after return from this exception handler the
75 * load / store will be re-executed.
76 */
77handle_vced:
78 MFC0 k0, CP0_BADVADDR
79 li k1, -4 # Is this ...
80 and k0, k1 # ... really needed?
81 mtc0 zero, CP0_TAGLO
82 cache Index_Store_Tag_D, (k0)
83 cache Hit_Writeback_Inv_SD, (k0)
84#ifdef CONFIG_PROC_FS
85 PTR_LA k0, vced_count
86 lw k1, (k0)
87 addiu k1, 1
88 sw k1, (k0)
89#endif
90 eret
91
92handle_vcei:
93 MFC0 k0, CP0_BADVADDR
94 cache Hit_Writeback_Inv_SD, (k0) # also cleans pi
95#ifdef CONFIG_PROC_FS
96 PTR_LA k0, vcei_count
97 lw k1, (k0)
98 addiu k1, 1
99 sw k1, (k0)
100#endif
101 eret
102 .set pop
103 END(except_vec3_r4000)
104
105 __FINIT
106
107 .align 5 /* 32 byte rollback region */
108LEAF(__r4k_wait)
109 .set push
110 .set noreorder
111 /* start of rollback region */
112 LONG_L t0, TI_FLAGS($28)
113 nop
114 andi t0, _TIF_NEED_RESCHED
115 bnez t0, 1f
116 nop
117 nop
118 nop
119#ifdef CONFIG_CPU_MICROMIPS
120 nop
121 nop
122 nop
123 nop
124#endif
125 .set MIPS_ISA_ARCH_LEVEL_RAW
126 wait
127 /* end of rollback region (the region size must be power of two) */
1281:
129 jr ra
130 nop
131 .set pop
132 END(__r4k_wait)
133
134 .macro BUILD_ROLLBACK_PROLOGUE handler
135 FEXPORT(rollback_\handler)
136 .set push
137 .set noat
138 MFC0 k0, CP0_EPC
139 PTR_LA k1, __r4k_wait
140 ori k0, 0x1f /* 32 byte rollback region */
141 xori k0, 0x1f
142 bne k0, k1, \handler
143 MTC0 k0, CP0_EPC
144 .set pop
145 .endm
146
147 .align 5
148BUILD_ROLLBACK_PROLOGUE handle_int
149NESTED(handle_int, PT_SIZE, sp)
150 .cfi_signal_frame
151#ifdef CONFIG_TRACE_IRQFLAGS
152 /*
153 * Check to see if the interrupted code has just disabled
154 * interrupts and ignore this interrupt for now if so.
155 *
156 * local_irq_disable() disables interrupts and then calls
157 * trace_hardirqs_off() to track the state. If an interrupt is taken
158 * after interrupts are disabled but before the state is updated
159 * it will appear to restore_all that it is incorrectly returning with
160 * interrupts disabled
161 */
162 .set push
163 .set noat
164 mfc0 k0, CP0_STATUS
165#if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)
166 and k0, ST0_IEP
167 bnez k0, 1f
168
169 mfc0 k0, CP0_EPC
170 .set noreorder
171 j k0
172 rfe
173#else
174 and k0, ST0_IE
175 bnez k0, 1f
176
177 eret
178#endif
1791:
180 .set pop
181#endif
182 SAVE_ALL docfi=1
183 CLI
184 TRACE_IRQS_OFF
185
186 LONG_L s0, TI_REGS($28)
187 LONG_S sp, TI_REGS($28)
188
189 /*
190 * SAVE_ALL ensures we are using a valid kernel stack for the thread.
191 * Check if we are already using the IRQ stack.
192 */
193 move s1, sp # Preserve the sp
194
195 /* Get IRQ stack for this CPU */
196 ASM_CPUID_MFC0 k0, ASM_SMP_CPUID_REG
197#if defined(CONFIG_32BIT) || defined(KBUILD_64BIT_SYM32)
198 lui k1, %hi(irq_stack)
199#else
200 lui k1, %highest(irq_stack)
201 daddiu k1, %higher(irq_stack)
202 dsll k1, 16
203 daddiu k1, %hi(irq_stack)
204 dsll k1, 16
205#endif
206 LONG_SRL k0, SMP_CPUID_PTRSHIFT
207 LONG_ADDU k1, k0
208 LONG_L t0, %lo(irq_stack)(k1)
209
210 # Check if already on IRQ stack
211 PTR_LI t1, ~(_THREAD_SIZE-1)
212 and t1, t1, sp
213 beq t0, t1, 2f
214
215 /* Switch to IRQ stack */
216 li t1, _IRQ_STACK_START
217 PTR_ADD sp, t0, t1
218
219 /* Save task's sp on IRQ stack so that unwinding can follow it */
220 LONG_S s1, 0(sp)
2212:
222 jal plat_irq_dispatch
223
224 /* Restore sp */
225 move sp, s1
226
227 j ret_from_irq
228#ifdef CONFIG_CPU_MICROMIPS
229 nop
230#endif
231 END(handle_int)
232
233 __INIT
234
235/*
236 * Special interrupt vector for MIPS64 ISA & embedded MIPS processors.
237 * This is a dedicated interrupt exception vector which reduces the
238 * interrupt processing overhead. The jump instruction will be replaced
239 * at the initialization time.
240 *
241 * Be careful when changing this, it has to be at most 128 bytes
242 * to fit into space reserved for the exception handler.
243 */
244NESTED(except_vec4, 0, sp)
2451: j 1b /* Dummy, will be replaced */
246 END(except_vec4)
247
248/*
249 * EJTAG debug exception handler.
250 * The EJTAG debug exception entry point is 0xbfc00480, which
251 * normally is in the boot PROM, so the boot PROM must do an
252 * unconditional jump to this vector.
253 */
254NESTED(except_vec_ejtag_debug, 0, sp)
255 j ejtag_debug_handler
256#ifdef CONFIG_CPU_MICROMIPS
257 nop
258#endif
259 END(except_vec_ejtag_debug)
260
261 __FINIT
262
263/*
264 * Vectored interrupt handler.
265 * This prototype is copied to ebase + n*IntCtl.VS and patched
266 * to invoke the handler
267 */
268BUILD_ROLLBACK_PROLOGUE except_vec_vi
269NESTED(except_vec_vi, 0, sp)
270 SAVE_SOME docfi=1
271 SAVE_AT docfi=1
272 .set push
273 .set noreorder
274 PTR_LA v1, except_vec_vi_handler
275FEXPORT(except_vec_vi_lui)
276 lui v0, 0 /* Patched */
277 jr v1
278FEXPORT(except_vec_vi_ori)
279 ori v0, 0 /* Patched */
280 .set pop
281 END(except_vec_vi)
282EXPORT(except_vec_vi_end)
283
284/*
285 * Common Vectored Interrupt code
286 * Complete the register saves and invoke the handler which is passed in $v0
287 */
288NESTED(except_vec_vi_handler, 0, sp)
289 SAVE_TEMP
290 SAVE_STATIC
291 CLI
292#ifdef CONFIG_TRACE_IRQFLAGS
293 move s0, v0
294 TRACE_IRQS_OFF
295 move v0, s0
296#endif
297
298 LONG_L s0, TI_REGS($28)
299 LONG_S sp, TI_REGS($28)
300
301 /*
302 * SAVE_ALL ensures we are using a valid kernel stack for the thread.
303 * Check if we are already using the IRQ stack.
304 */
305 move s1, sp # Preserve the sp
306
307 /* Get IRQ stack for this CPU */
308 ASM_CPUID_MFC0 k0, ASM_SMP_CPUID_REG
309#if defined(CONFIG_32BIT) || defined(KBUILD_64BIT_SYM32)
310 lui k1, %hi(irq_stack)
311#else
312 lui k1, %highest(irq_stack)
313 daddiu k1, %higher(irq_stack)
314 dsll k1, 16
315 daddiu k1, %hi(irq_stack)
316 dsll k1, 16
317#endif
318 LONG_SRL k0, SMP_CPUID_PTRSHIFT
319 LONG_ADDU k1, k0
320 LONG_L t0, %lo(irq_stack)(k1)
321
322 # Check if already on IRQ stack
323 PTR_LI t1, ~(_THREAD_SIZE-1)
324 and t1, t1, sp
325 beq t0, t1, 2f
326
327 /* Switch to IRQ stack */
328 li t1, _IRQ_STACK_START
329 PTR_ADD sp, t0, t1
330
331 /* Save task's sp on IRQ stack so that unwinding can follow it */
332 LONG_S s1, 0(sp)
3332:
334 jalr v0
335
336 /* Restore sp */
337 move sp, s1
338
339 j ret_from_irq
340 END(except_vec_vi_handler)
341
342/*
343 * EJTAG debug exception handler.
344 */
345NESTED(ejtag_debug_handler, PT_SIZE, sp)
346 .set push
347 .set noat
348 MTC0 k0, CP0_DESAVE
349 mfc0 k0, CP0_DEBUG
350
351 sll k0, k0, 30 # Check for SDBBP.
352 bgez k0, ejtag_return
353
354#ifdef CONFIG_SMP
3551: PTR_LA k0, ejtag_debug_buffer_spinlock
356 ll k0, 0(k0)
357 bnez k0, 1b
358 PTR_LA k0, ejtag_debug_buffer_spinlock
359 sc k0, 0(k0)
360 beqz k0, 1b
361# ifdef CONFIG_WEAK_REORDERING_BEYOND_LLSC
362 sync
363# endif
364
365 PTR_LA k0, ejtag_debug_buffer
366 LONG_S k1, 0(k0)
367
368 ASM_CPUID_MFC0 k1, ASM_SMP_CPUID_REG
369 PTR_SRL k1, SMP_CPUID_PTRSHIFT
370 PTR_SLL k1, LONGLOG
371 PTR_LA k0, ejtag_debug_buffer_per_cpu
372 PTR_ADDU k0, k1
373
374 PTR_LA k1, ejtag_debug_buffer
375 LONG_L k1, 0(k1)
376 LONG_S k1, 0(k0)
377
378 PTR_LA k0, ejtag_debug_buffer_spinlock
379 sw zero, 0(k0)
380#else
381 PTR_LA k0, ejtag_debug_buffer
382 LONG_S k1, 0(k0)
383#endif
384
385 SAVE_ALL
386 move a0, sp
387 jal ejtag_exception_handler
388 RESTORE_ALL
389
390#ifdef CONFIG_SMP
391 ASM_CPUID_MFC0 k1, ASM_SMP_CPUID_REG
392 PTR_SRL k1, SMP_CPUID_PTRSHIFT
393 PTR_SLL k1, LONGLOG
394 PTR_LA k0, ejtag_debug_buffer_per_cpu
395 PTR_ADDU k0, k1
396 LONG_L k1, 0(k0)
397#else
398 PTR_LA k0, ejtag_debug_buffer
399 LONG_L k1, 0(k0)
400#endif
401
402ejtag_return:
403 back_to_back_c0_hazard
404 MFC0 k0, CP0_DESAVE
405 .set mips32
406 deret
407 .set pop
408 END(ejtag_debug_handler)
409
410/*
411 * This buffer is reserved for the use of the EJTAG debug
412 * handler.
413 */
414 .data
415EXPORT(ejtag_debug_buffer)
416 .fill LONGSIZE
417#ifdef CONFIG_SMP
418EXPORT(ejtag_debug_buffer_spinlock)
419 .fill LONGSIZE
420EXPORT(ejtag_debug_buffer_per_cpu)
421 .fill LONGSIZE * NR_CPUS
422#endif
423 .previous
424
425 __INIT
426
427/*
428 * NMI debug exception handler for MIPS reference boards.
429 * The NMI debug exception entry point is 0xbfc00000, which
430 * normally is in the boot PROM, so the boot PROM must do a
431 * unconditional jump to this vector.
432 */
433NESTED(except_vec_nmi, 0, sp)
434 j nmi_handler
435#ifdef CONFIG_CPU_MICROMIPS
436 nop
437#endif
438 END(except_vec_nmi)
439
440 __FINIT
441
442NESTED(nmi_handler, PT_SIZE, sp)
443 .cfi_signal_frame
444 .set push
445 .set noat
446 /*
447 * Clear ERL - restore segment mapping
448 * Clear BEV - required for page fault exception handler to work
449 */
450 mfc0 k0, CP0_STATUS
451 ori k0, k0, ST0_EXL
452 li k1, ~(ST0_BEV | ST0_ERL)
453 and k0, k0, k1
454 mtc0 k0, CP0_STATUS
455 _ehb
456 SAVE_ALL
457 move a0, sp
458 jal nmi_exception_handler
459 /* nmi_exception_handler never returns */
460 .set pop
461 END(nmi_handler)
462
463 .macro __build_clear_none
464 .endm
465
466 .macro __build_clear_sti
467 TRACE_IRQS_ON
468 STI
469 .endm
470
471 .macro __build_clear_cli
472 CLI
473 TRACE_IRQS_OFF
474 .endm
475
476 .macro __build_clear_fpe
477 .set push
478 /* gas fails to assemble cfc1 for some archs (octeon).*/ \
479 .set mips1
480 SET_HARDFLOAT
481 cfc1 a1, fcr31
482 .set pop
483 CLI
484 TRACE_IRQS_OFF
485 .endm
486
487 .macro __build_clear_msa_fpe
488 _cfcmsa a1, MSA_CSR
489 CLI
490 TRACE_IRQS_OFF
491 .endm
492
493 .macro __build_clear_ade
494 MFC0 t0, CP0_BADVADDR
495 PTR_S t0, PT_BVADDR(sp)
496 KMODE
497 .endm
498
499 .macro __BUILD_silent exception
500 .endm
501
502 /* Gas tries to parse the PRINT argument as a string containing
503 string escapes and emits bogus warnings if it believes to
504 recognize an unknown escape code. So make the arguments
505 start with an n and gas will believe \n is ok ... */
506 .macro __BUILD_verbose nexception
507 LONG_L a1, PT_EPC(sp)
508#ifdef CONFIG_32BIT
509 PRINT("Got \nexception at %08lx\012")
510#endif
511#ifdef CONFIG_64BIT
512 PRINT("Got \nexception at %016lx\012")
513#endif
514 .endm
515
516 .macro __BUILD_count exception
517 LONG_L t0,exception_count_\exception
518 LONG_ADDIU t0, 1
519 LONG_S t0,exception_count_\exception
520 .comm exception_count\exception, 8, 8
521 .endm
522
523 .macro __BUILD_HANDLER exception handler clear verbose ext
524 .align 5
525 NESTED(handle_\exception, PT_SIZE, sp)
526 .cfi_signal_frame
527 .set noat
528 SAVE_ALL
529 FEXPORT(handle_\exception\ext)
530 __build_clear_\clear
531 .set at
532 __BUILD_\verbose \exception
533 move a0, sp
534 jal do_\handler
535 j ret_from_exception
536 END(handle_\exception)
537 .endm
538
539 .macro BUILD_HANDLER exception handler clear verbose
540 __BUILD_HANDLER \exception \handler \clear \verbose _int
541 .endm
542
543 BUILD_HANDLER adel ade ade silent /* #4 */
544 BUILD_HANDLER ades ade ade silent /* #5 */
545 BUILD_HANDLER ibe be cli silent /* #6 */
546 BUILD_HANDLER dbe be cli silent /* #7 */
547 BUILD_HANDLER bp bp sti silent /* #9 */
548 BUILD_HANDLER ri ri sti silent /* #10 */
549 BUILD_HANDLER cpu cpu sti silent /* #11 */
550 BUILD_HANDLER ov ov sti silent /* #12 */
551 BUILD_HANDLER tr tr sti silent /* #13 */
552 BUILD_HANDLER msa_fpe msa_fpe msa_fpe silent /* #14 */
553#ifdef CONFIG_MIPS_FP_SUPPORT
554 BUILD_HANDLER fpe fpe fpe silent /* #15 */
555#endif
556 BUILD_HANDLER ftlb ftlb none silent /* #16 */
557 BUILD_HANDLER msa msa sti silent /* #21 */
558 BUILD_HANDLER mdmx mdmx sti silent /* #22 */
559#ifdef CONFIG_HARDWARE_WATCHPOINTS
560 /*
561 * For watch, interrupts will be enabled after the watch
562 * registers are read.
563 */
564 BUILD_HANDLER watch watch cli silent /* #23 */
565#else
566 BUILD_HANDLER watch watch sti verbose /* #23 */
567#endif
568 BUILD_HANDLER mcheck mcheck cli verbose /* #24 */
569 BUILD_HANDLER mt mt sti silent /* #25 */
570 BUILD_HANDLER dsp dsp sti silent /* #26 */
571 BUILD_HANDLER reserved reserved sti verbose /* others */
572
573 .align 5
574 LEAF(handle_ri_rdhwr_tlbp)
575 .set push
576 .set noat
577 .set noreorder
578 /* check if TLB contains a entry for EPC */
579 MFC0 k1, CP0_ENTRYHI
580 andi k1, MIPS_ENTRYHI_ASID | MIPS_ENTRYHI_ASIDX
581 MFC0 k0, CP0_EPC
582 PTR_SRL k0, _PAGE_SHIFT + 1
583 PTR_SLL k0, _PAGE_SHIFT + 1
584 or k1, k0
585 MTC0 k1, CP0_ENTRYHI
586 mtc0_tlbw_hazard
587 tlbp
588 tlb_probe_hazard
589 mfc0 k1, CP0_INDEX
590 .set pop
591 bltz k1, handle_ri /* slow path */
592 /* fall thru */
593 END(handle_ri_rdhwr_tlbp)
594
595 LEAF(handle_ri_rdhwr)
596 .set push
597 .set noat
598 .set noreorder
599 /* MIPS32: 0x7c03e83b: rdhwr v1,$29 */
600 /* microMIPS: 0x007d6b3c: rdhwr v1,$29 */
601 MFC0 k1, CP0_EPC
602#if defined(CONFIG_CPU_MICROMIPS) || defined(CONFIG_CPU_MIPS32_R2) || defined(CONFIG_CPU_MIPS64_R2)
603 and k0, k1, 1
604 beqz k0, 1f
605 xor k1, k0
606 lhu k0, (k1)
607 lhu k1, 2(k1)
608 ins k1, k0, 16, 16
609 lui k0, 0x007d
610 b docheck
611 ori k0, 0x6b3c
6121:
613 lui k0, 0x7c03
614 lw k1, (k1)
615 ori k0, 0xe83b
616#else
617 andi k0, k1, 1
618 bnez k0, handle_ri
619 lui k0, 0x7c03
620 lw k1, (k1)
621 ori k0, 0xe83b
622#endif
623 .set reorder
624docheck:
625 bne k0, k1, handle_ri /* if not ours */
626
627isrdhwr:
628 /* The insn is rdhwr. No need to check CAUSE.BD here. */
629 get_saved_sp /* k1 := current_thread_info */
630 .set noreorder
631 MFC0 k0, CP0_EPC
632#if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)
633 ori k1, _THREAD_MASK
634 xori k1, _THREAD_MASK
635 LONG_L v1, TI_TP_VALUE(k1)
636 LONG_ADDIU k0, 4
637 jr k0
638 rfe
639#else
640#ifndef CONFIG_CPU_DADDI_WORKAROUNDS
641 LONG_ADDIU k0, 4 /* stall on $k0 */
642#else
643 .set at=v1
644 LONG_ADDIU k0, 4
645 .set noat
646#endif
647 MTC0 k0, CP0_EPC
648 /* I hope three instructions between MTC0 and ERET are enough... */
649 ori k1, _THREAD_MASK
650 xori k1, _THREAD_MASK
651 LONG_L v1, TI_TP_VALUE(k1)
652 .set push
653 .set arch=r4000
654 eret
655 .set pop
656#endif
657 .set pop
658 END(handle_ri_rdhwr)
659
660#ifdef CONFIG_64BIT
661/* A temporary overflow handler used by check_daddi(). */
662
663 __INIT
664
665 BUILD_HANDLER daddi_ov daddi_ov none silent /* #12 */
666#endif
1/*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * Copyright (C) 1994 - 2000, 2001, 2003 Ralf Baechle
7 * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
8 * Copyright (C) 2002, 2007 Maciej W. Rozycki
9 * Copyright (C) 2001, 2012 MIPS Technologies, Inc. All rights reserved.
10 */
11#include <linux/init.h>
12
13#include <asm/asm.h>
14#include <asm/asmmacro.h>
15#include <asm/cacheops.h>
16#include <asm/irqflags.h>
17#include <asm/regdef.h>
18#include <asm/fpregdef.h>
19#include <asm/mipsregs.h>
20#include <asm/stackframe.h>
21#include <asm/war.h>
22#include <asm/thread_info.h>
23
24 __INIT
25
26/*
27 * General exception vector for all other CPUs.
28 *
29 * Be careful when changing this, it has to be at most 128 bytes
30 * to fit into space reserved for the exception handler.
31 */
32NESTED(except_vec3_generic, 0, sp)
33 .set push
34 .set noat
35#if R5432_CP0_INTERRUPT_WAR
36 mfc0 k0, CP0_INDEX
37#endif
38 mfc0 k1, CP0_CAUSE
39 andi k1, k1, 0x7c
40#ifdef CONFIG_64BIT
41 dsll k1, k1, 1
42#endif
43 PTR_L k0, exception_handlers(k1)
44 jr k0
45 .set pop
46 END(except_vec3_generic)
47
48/*
49 * General exception handler for CPUs with virtual coherency exception.
50 *
51 * Be careful when changing this, it has to be at most 256 (as a special
52 * exception) bytes to fit into space reserved for the exception handler.
53 */
54NESTED(except_vec3_r4000, 0, sp)
55 .set push
56 .set arch=r4000
57 .set noat
58 mfc0 k1, CP0_CAUSE
59 li k0, 31<<2
60 andi k1, k1, 0x7c
61 .set push
62 .set noreorder
63 .set nomacro
64 beq k1, k0, handle_vced
65 li k0, 14<<2
66 beq k1, k0, handle_vcei
67#ifdef CONFIG_64BIT
68 dsll k1, k1, 1
69#endif
70 .set pop
71 PTR_L k0, exception_handlers(k1)
72 jr k0
73
74 /*
75 * Big shit, we now may have two dirty primary cache lines for the same
76 * physical address. We can safely invalidate the line pointed to by
77 * c0_badvaddr because after return from this exception handler the
78 * load / store will be re-executed.
79 */
80handle_vced:
81 MFC0 k0, CP0_BADVADDR
82 li k1, -4 # Is this ...
83 and k0, k1 # ... really needed?
84 mtc0 zero, CP0_TAGLO
85 cache Index_Store_Tag_D, (k0)
86 cache Hit_Writeback_Inv_SD, (k0)
87#ifdef CONFIG_PROC_FS
88 PTR_LA k0, vced_count
89 lw k1, (k0)
90 addiu k1, 1
91 sw k1, (k0)
92#endif
93 eret
94
95handle_vcei:
96 MFC0 k0, CP0_BADVADDR
97 cache Hit_Writeback_Inv_SD, (k0) # also cleans pi
98#ifdef CONFIG_PROC_FS
99 PTR_LA k0, vcei_count
100 lw k1, (k0)
101 addiu k1, 1
102 sw k1, (k0)
103#endif
104 eret
105 .set pop
106 END(except_vec3_r4000)
107
108 __FINIT
109
110 .align 5 /* 32 byte rollback region */
111LEAF(__r4k_wait)
112 .set push
113 .set noreorder
114 /* start of rollback region */
115 LONG_L t0, TI_FLAGS($28)
116 nop
117 andi t0, _TIF_NEED_RESCHED
118 bnez t0, 1f
119 nop
120 nop
121 nop
122#ifdef CONFIG_CPU_MICROMIPS
123 nop
124 nop
125 nop
126 nop
127#endif
128 .set MIPS_ISA_ARCH_LEVEL_RAW
129 wait
130 /* end of rollback region (the region size must be power of two) */
1311:
132 jr ra
133 nop
134 .set pop
135 END(__r4k_wait)
136
137 .macro BUILD_ROLLBACK_PROLOGUE handler
138 FEXPORT(rollback_\handler)
139 .set push
140 .set noat
141 MFC0 k0, CP0_EPC
142 PTR_LA k1, __r4k_wait
143 ori k0, 0x1f /* 32 byte rollback region */
144 xori k0, 0x1f
145 bne k0, k1, \handler
146 MTC0 k0, CP0_EPC
147 .set pop
148 .endm
149
150 .align 5
151BUILD_ROLLBACK_PROLOGUE handle_int
152NESTED(handle_int, PT_SIZE, sp)
153#ifdef CONFIG_TRACE_IRQFLAGS
154 /*
155 * Check to see if the interrupted code has just disabled
156 * interrupts and ignore this interrupt for now if so.
157 *
158 * local_irq_disable() disables interrupts and then calls
159 * trace_hardirqs_off() to track the state. If an interrupt is taken
160 * after interrupts are disabled but before the state is updated
161 * it will appear to restore_all that it is incorrectly returning with
162 * interrupts disabled
163 */
164 .set push
165 .set noat
166 mfc0 k0, CP0_STATUS
167#if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)
168 and k0, ST0_IEP
169 bnez k0, 1f
170
171 mfc0 k0, CP0_EPC
172 .set noreorder
173 j k0
174 rfe
175#else
176 and k0, ST0_IE
177 bnez k0, 1f
178
179 eret
180#endif
1811:
182 .set pop
183#endif
184 SAVE_ALL
185 CLI
186 TRACE_IRQS_OFF
187
188 LONG_L s0, TI_REGS($28)
189 LONG_S sp, TI_REGS($28)
190
191 /*
192 * SAVE_ALL ensures we are using a valid kernel stack for the thread.
193 * Check if we are already using the IRQ stack.
194 */
195 move s1, sp # Preserve the sp
196
197 /* Get IRQ stack for this CPU */
198 ASM_CPUID_MFC0 k0, ASM_SMP_CPUID_REG
199#if defined(CONFIG_32BIT) || defined(KBUILD_64BIT_SYM32)
200 lui k1, %hi(irq_stack)
201#else
202 lui k1, %highest(irq_stack)
203 daddiu k1, %higher(irq_stack)
204 dsll k1, 16
205 daddiu k1, %hi(irq_stack)
206 dsll k1, 16
207#endif
208 LONG_SRL k0, SMP_CPUID_PTRSHIFT
209 LONG_ADDU k1, k0
210 LONG_L t0, %lo(irq_stack)(k1)
211
212 # Check if already on IRQ stack
213 PTR_LI t1, ~(_THREAD_SIZE-1)
214 and t1, t1, sp
215 beq t0, t1, 2f
216
217 /* Switch to IRQ stack */
218 li t1, _IRQ_STACK_SIZE
219 PTR_ADD sp, t0, t1
220
2212:
222 jal plat_irq_dispatch
223
224 /* Restore sp */
225 move sp, s1
226
227 j ret_from_irq
228#ifdef CONFIG_CPU_MICROMIPS
229 nop
230#endif
231 END(handle_int)
232
233 __INIT
234
235/*
236 * Special interrupt vector for MIPS64 ISA & embedded MIPS processors.
237 * This is a dedicated interrupt exception vector which reduces the
238 * interrupt processing overhead. The jump instruction will be replaced
239 * at the initialization time.
240 *
241 * Be careful when changing this, it has to be at most 128 bytes
242 * to fit into space reserved for the exception handler.
243 */
244NESTED(except_vec4, 0, sp)
2451: j 1b /* Dummy, will be replaced */
246 END(except_vec4)
247
248/*
249 * EJTAG debug exception handler.
250 * The EJTAG debug exception entry point is 0xbfc00480, which
251 * normally is in the boot PROM, so the boot PROM must do an
252 * unconditional jump to this vector.
253 */
254NESTED(except_vec_ejtag_debug, 0, sp)
255 j ejtag_debug_handler
256#ifdef CONFIG_CPU_MICROMIPS
257 nop
258#endif
259 END(except_vec_ejtag_debug)
260
261 __FINIT
262
263/*
264 * Vectored interrupt handler.
265 * This prototype is copied to ebase + n*IntCtl.VS and patched
266 * to invoke the handler
267 */
268BUILD_ROLLBACK_PROLOGUE except_vec_vi
269NESTED(except_vec_vi, 0, sp)
270 SAVE_SOME
271 SAVE_AT
272 .set push
273 .set noreorder
274 PTR_LA v1, except_vec_vi_handler
275FEXPORT(except_vec_vi_lui)
276 lui v0, 0 /* Patched */
277 jr v1
278FEXPORT(except_vec_vi_ori)
279 ori v0, 0 /* Patched */
280 .set pop
281 END(except_vec_vi)
282EXPORT(except_vec_vi_end)
283
284/*
285 * Common Vectored Interrupt code
286 * Complete the register saves and invoke the handler which is passed in $v0
287 */
288NESTED(except_vec_vi_handler, 0, sp)
289 SAVE_TEMP
290 SAVE_STATIC
291 CLI
292#ifdef CONFIG_TRACE_IRQFLAGS
293 move s0, v0
294 TRACE_IRQS_OFF
295 move v0, s0
296#endif
297
298 LONG_L s0, TI_REGS($28)
299 LONG_S sp, TI_REGS($28)
300
301 /*
302 * SAVE_ALL ensures we are using a valid kernel stack for the thread.
303 * Check if we are already using the IRQ stack.
304 */
305 move s1, sp # Preserve the sp
306
307 /* Get IRQ stack for this CPU */
308 ASM_CPUID_MFC0 k0, ASM_SMP_CPUID_REG
309#if defined(CONFIG_32BIT) || defined(KBUILD_64BIT_SYM32)
310 lui k1, %hi(irq_stack)
311#else
312 lui k1, %highest(irq_stack)
313 daddiu k1, %higher(irq_stack)
314 dsll k1, 16
315 daddiu k1, %hi(irq_stack)
316 dsll k1, 16
317#endif
318 LONG_SRL k0, SMP_CPUID_PTRSHIFT
319 LONG_ADDU k1, k0
320 LONG_L t0, %lo(irq_stack)(k1)
321
322 # Check if already on IRQ stack
323 PTR_LI t1, ~(_THREAD_SIZE-1)
324 and t1, t1, sp
325 beq t0, t1, 2f
326
327 /* Switch to IRQ stack */
328 li t1, _IRQ_STACK_SIZE
329 PTR_ADD sp, t0, t1
330
3312:
332 jalr v0
333
334 /* Restore sp */
335 move sp, s1
336
337 j ret_from_irq
338 END(except_vec_vi_handler)
339
340/*
341 * EJTAG debug exception handler.
342 */
343NESTED(ejtag_debug_handler, PT_SIZE, sp)
344 .set push
345 .set noat
346 MTC0 k0, CP0_DESAVE
347 mfc0 k0, CP0_DEBUG
348
349 sll k0, k0, 30 # Check for SDBBP.
350 bgez k0, ejtag_return
351
352 PTR_LA k0, ejtag_debug_buffer
353 LONG_S k1, 0(k0)
354 SAVE_ALL
355 move a0, sp
356 jal ejtag_exception_handler
357 RESTORE_ALL
358 PTR_LA k0, ejtag_debug_buffer
359 LONG_L k1, 0(k0)
360
361ejtag_return:
362 MFC0 k0, CP0_DESAVE
363 .set mips32
364 deret
365 .set pop
366 END(ejtag_debug_handler)
367
368/*
369 * This buffer is reserved for the use of the EJTAG debug
370 * handler.
371 */
372 .data
373EXPORT(ejtag_debug_buffer)
374 .fill LONGSIZE
375 .previous
376
377 __INIT
378
379/*
380 * NMI debug exception handler for MIPS reference boards.
381 * The NMI debug exception entry point is 0xbfc00000, which
382 * normally is in the boot PROM, so the boot PROM must do a
383 * unconditional jump to this vector.
384 */
385NESTED(except_vec_nmi, 0, sp)
386 j nmi_handler
387#ifdef CONFIG_CPU_MICROMIPS
388 nop
389#endif
390 END(except_vec_nmi)
391
392 __FINIT
393
394NESTED(nmi_handler, PT_SIZE, sp)
395 .set push
396 .set noat
397 /*
398 * Clear ERL - restore segment mapping
399 * Clear BEV - required for page fault exception handler to work
400 */
401 mfc0 k0, CP0_STATUS
402 ori k0, k0, ST0_EXL
403 li k1, ~(ST0_BEV | ST0_ERL)
404 and k0, k0, k1
405 mtc0 k0, CP0_STATUS
406 _ehb
407 SAVE_ALL
408 move a0, sp
409 jal nmi_exception_handler
410 /* nmi_exception_handler never returns */
411 .set pop
412 END(nmi_handler)
413
414 .macro __build_clear_none
415 .endm
416
417 .macro __build_clear_sti
418 TRACE_IRQS_ON
419 STI
420 .endm
421
422 .macro __build_clear_cli
423 CLI
424 TRACE_IRQS_OFF
425 .endm
426
427 .macro __build_clear_fpe
428 .set push
429 /* gas fails to assemble cfc1 for some archs (octeon).*/ \
430 .set mips1
431 SET_HARDFLOAT
432 cfc1 a1, fcr31
433 .set pop
434 CLI
435 TRACE_IRQS_OFF
436 .endm
437
438 .macro __build_clear_msa_fpe
439 _cfcmsa a1, MSA_CSR
440 CLI
441 TRACE_IRQS_OFF
442 .endm
443
444 .macro __build_clear_ade
445 MFC0 t0, CP0_BADVADDR
446 PTR_S t0, PT_BVADDR(sp)
447 KMODE
448 .endm
449
450 .macro __BUILD_silent exception
451 .endm
452
453 /* Gas tries to parse the PRINT argument as a string containing
454 string escapes and emits bogus warnings if it believes to
455 recognize an unknown escape code. So make the arguments
456 start with an n and gas will believe \n is ok ... */
457 .macro __BUILD_verbose nexception
458 LONG_L a1, PT_EPC(sp)
459#ifdef CONFIG_32BIT
460 PRINT("Got \nexception at %08lx\012")
461#endif
462#ifdef CONFIG_64BIT
463 PRINT("Got \nexception at %016lx\012")
464#endif
465 .endm
466
467 .macro __BUILD_count exception
468 LONG_L t0,exception_count_\exception
469 LONG_ADDIU t0, 1
470 LONG_S t0,exception_count_\exception
471 .comm exception_count\exception, 8, 8
472 .endm
473
474 .macro __BUILD_HANDLER exception handler clear verbose ext
475 .align 5
476 NESTED(handle_\exception, PT_SIZE, sp)
477 .set noat
478 SAVE_ALL
479 FEXPORT(handle_\exception\ext)
480 __build_clear_\clear
481 .set at
482 __BUILD_\verbose \exception
483 move a0, sp
484 PTR_LA ra, ret_from_exception
485 j do_\handler
486 END(handle_\exception)
487 .endm
488
489 .macro BUILD_HANDLER exception handler clear verbose
490 __BUILD_HANDLER \exception \handler \clear \verbose _int
491 .endm
492
493 BUILD_HANDLER adel ade ade silent /* #4 */
494 BUILD_HANDLER ades ade ade silent /* #5 */
495 BUILD_HANDLER ibe be cli silent /* #6 */
496 BUILD_HANDLER dbe be cli silent /* #7 */
497 BUILD_HANDLER bp bp sti silent /* #9 */
498 BUILD_HANDLER ri ri sti silent /* #10 */
499 BUILD_HANDLER cpu cpu sti silent /* #11 */
500 BUILD_HANDLER ov ov sti silent /* #12 */
501 BUILD_HANDLER tr tr sti silent /* #13 */
502 BUILD_HANDLER msa_fpe msa_fpe msa_fpe silent /* #14 */
503 BUILD_HANDLER fpe fpe fpe silent /* #15 */
504 BUILD_HANDLER ftlb ftlb none silent /* #16 */
505 BUILD_HANDLER msa msa sti silent /* #21 */
506 BUILD_HANDLER mdmx mdmx sti silent /* #22 */
507#ifdef CONFIG_HARDWARE_WATCHPOINTS
508 /*
509 * For watch, interrupts will be enabled after the watch
510 * registers are read.
511 */
512 BUILD_HANDLER watch watch cli silent /* #23 */
513#else
514 BUILD_HANDLER watch watch sti verbose /* #23 */
515#endif
516 BUILD_HANDLER mcheck mcheck cli verbose /* #24 */
517 BUILD_HANDLER mt mt sti silent /* #25 */
518 BUILD_HANDLER dsp dsp sti silent /* #26 */
519 BUILD_HANDLER reserved reserved sti verbose /* others */
520
521 .align 5
522 LEAF(handle_ri_rdhwr_tlbp)
523 .set push
524 .set noat
525 .set noreorder
526 /* check if TLB contains a entry for EPC */
527 MFC0 k1, CP0_ENTRYHI
528 andi k1, MIPS_ENTRYHI_ASID | MIPS_ENTRYHI_ASIDX
529 MFC0 k0, CP0_EPC
530 PTR_SRL k0, _PAGE_SHIFT + 1
531 PTR_SLL k0, _PAGE_SHIFT + 1
532 or k1, k0
533 MTC0 k1, CP0_ENTRYHI
534 mtc0_tlbw_hazard
535 tlbp
536 tlb_probe_hazard
537 mfc0 k1, CP0_INDEX
538 .set pop
539 bltz k1, handle_ri /* slow path */
540 /* fall thru */
541 END(handle_ri_rdhwr_tlbp)
542
543 LEAF(handle_ri_rdhwr)
544 .set push
545 .set noat
546 .set noreorder
547 /* MIPS32: 0x7c03e83b: rdhwr v1,$29 */
548 /* microMIPS: 0x007d6b3c: rdhwr v1,$29 */
549 MFC0 k1, CP0_EPC
550#if defined(CONFIG_CPU_MICROMIPS) || defined(CONFIG_CPU_MIPS32_R2) || defined(CONFIG_CPU_MIPS64_R2)
551 and k0, k1, 1
552 beqz k0, 1f
553 xor k1, k0
554 lhu k0, (k1)
555 lhu k1, 2(k1)
556 ins k1, k0, 16, 16
557 lui k0, 0x007d
558 b docheck
559 ori k0, 0x6b3c
5601:
561 lui k0, 0x7c03
562 lw k1, (k1)
563 ori k0, 0xe83b
564#else
565 andi k0, k1, 1
566 bnez k0, handle_ri
567 lui k0, 0x7c03
568 lw k1, (k1)
569 ori k0, 0xe83b
570#endif
571 .set reorder
572docheck:
573 bne k0, k1, handle_ri /* if not ours */
574
575isrdhwr:
576 /* The insn is rdhwr. No need to check CAUSE.BD here. */
577 get_saved_sp /* k1 := current_thread_info */
578 .set noreorder
579 MFC0 k0, CP0_EPC
580#if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)
581 ori k1, _THREAD_MASK
582 xori k1, _THREAD_MASK
583 LONG_L v1, TI_TP_VALUE(k1)
584 LONG_ADDIU k0, 4
585 jr k0
586 rfe
587#else
588#ifndef CONFIG_CPU_DADDI_WORKAROUNDS
589 LONG_ADDIU k0, 4 /* stall on $k0 */
590#else
591 .set at=v1
592 LONG_ADDIU k0, 4
593 .set noat
594#endif
595 MTC0 k0, CP0_EPC
596 /* I hope three instructions between MTC0 and ERET are enough... */
597 ori k1, _THREAD_MASK
598 xori k1, _THREAD_MASK
599 LONG_L v1, TI_TP_VALUE(k1)
600 .set arch=r4000
601 eret
602 .set mips0
603#endif
604 .set pop
605 END(handle_ri_rdhwr)
606
607#ifdef CONFIG_64BIT
608/* A temporary overflow handler used by check_daddi(). */
609
610 __INIT
611
612 BUILD_HANDLER daddi_ov daddi_ov none silent /* #12 */
613#endif