Loading...
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/sync.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)
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 andi k0, k0, MIPS_DEBUG_DBP # Check for SDBBP.
352 beqz k0, ejtag_return
353
354#ifdef CONFIG_SMP
3551: PTR_LA k0, ejtag_debug_buffer_spinlock
356 __SYNC(full, loongson3_war)
3572: ll k0, 0(k0)
358 bnez k0, 2b
359 PTR_LA k0, ejtag_debug_buffer_spinlock
360 sc k0, 0(k0)
361 beqz k0, 1b
362# ifdef CONFIG_WEAK_REORDERING_BEYOND_LLSC
363 sync
364# endif
365
366 PTR_LA k0, ejtag_debug_buffer
367 LONG_S k1, 0(k0)
368
369 ASM_CPUID_MFC0 k1, ASM_SMP_CPUID_REG
370 PTR_SRL k1, SMP_CPUID_PTRSHIFT
371 PTR_SLL k1, LONGLOG
372 PTR_LA k0, ejtag_debug_buffer_per_cpu
373 PTR_ADDU k0, k1
374
375 PTR_LA k1, ejtag_debug_buffer
376 LONG_L k1, 0(k1)
377 LONG_S k1, 0(k0)
378
379 PTR_LA k0, ejtag_debug_buffer_spinlock
380 sw zero, 0(k0)
381#else
382 PTR_LA k0, ejtag_debug_buffer
383 LONG_S k1, 0(k0)
384#endif
385
386 SAVE_ALL
387 move a0, sp
388 jal ejtag_exception_handler
389 RESTORE_ALL
390
391#ifdef CONFIG_SMP
392 ASM_CPUID_MFC0 k1, ASM_SMP_CPUID_REG
393 PTR_SRL k1, SMP_CPUID_PTRSHIFT
394 PTR_SLL k1, LONGLOG
395 PTR_LA k0, ejtag_debug_buffer_per_cpu
396 PTR_ADDU k0, k1
397 LONG_L k1, 0(k0)
398#else
399 PTR_LA k0, ejtag_debug_buffer
400 LONG_L k1, 0(k0)
401#endif
402
403ejtag_return:
404 back_to_back_c0_hazard
405 MFC0 k0, CP0_DESAVE
406 .set mips32
407 deret
408 .set pop
409 END(ejtag_debug_handler)
410
411/*
412 * This buffer is reserved for the use of the EJTAG debug
413 * handler.
414 */
415 .data
416EXPORT(ejtag_debug_buffer)
417 .fill LONGSIZE
418#ifdef CONFIG_SMP
419EXPORT(ejtag_debug_buffer_spinlock)
420 .fill LONGSIZE
421EXPORT(ejtag_debug_buffer_per_cpu)
422 .fill LONGSIZE * NR_CPUS
423#endif
424 .previous
425
426 __INIT
427
428/*
429 * NMI debug exception handler for MIPS reference boards.
430 * The NMI debug exception entry point is 0xbfc00000, which
431 * normally is in the boot PROM, so the boot PROM must do a
432 * unconditional jump to this vector.
433 */
434NESTED(except_vec_nmi, 0, sp)
435 j nmi_handler
436#ifdef CONFIG_CPU_MICROMIPS
437 nop
438#endif
439 END(except_vec_nmi)
440
441 __FINIT
442
443NESTED(nmi_handler, PT_SIZE, sp)
444 .cfi_signal_frame
445 .set push
446 .set noat
447 /*
448 * Clear ERL - restore segment mapping
449 * Clear BEV - required for page fault exception handler to work
450 */
451 mfc0 k0, CP0_STATUS
452 ori k0, k0, ST0_EXL
453 li k1, ~(ST0_BEV | ST0_ERL)
454 and k0, k0, k1
455 mtc0 k0, CP0_STATUS
456 _ehb
457 SAVE_ALL
458 move a0, sp
459 jal nmi_exception_handler
460 /* nmi_exception_handler never returns */
461 .set pop
462 END(nmi_handler)
463
464 .macro __build_clear_none
465 .endm
466
467 .macro __build_clear_sti
468 TRACE_IRQS_ON
469 STI
470 .endm
471
472 .macro __build_clear_cli
473 CLI
474 TRACE_IRQS_OFF
475 .endm
476
477 .macro __build_clear_fpe
478 CLI
479 TRACE_IRQS_OFF
480 .set push
481 /* gas fails to assemble cfc1 for some archs (octeon).*/ \
482 .set mips1
483 SET_HARDFLOAT
484 cfc1 a1, fcr31
485 .set pop
486 .endm
487
488 .macro __build_clear_msa_fpe
489 CLI
490 TRACE_IRQS_OFF
491 _cfcmsa a1, MSA_CSR
492 .endm
493
494 .macro __build_clear_ade
495 MFC0 t0, CP0_BADVADDR
496 PTR_S t0, PT_BVADDR(sp)
497 KMODE
498 .endm
499
500 .macro __build_clear_gsexc
501 .set push
502 /*
503 * We need to specify a selector to access the CP0.Diag1 (GSCause)
504 * register. All GSExc-equipped processors have MIPS32.
505 */
506 .set mips32
507 mfc0 a1, CP0_DIAGNOSTIC1
508 .set pop
509 TRACE_IRQS_ON
510 STI
511 .endm
512
513 .macro __BUILD_silent exception
514 .endm
515
516 /* Gas tries to parse the ASM_PRINT argument as a string containing
517 string escapes and emits bogus warnings if it believes to
518 recognize an unknown escape code. So make the arguments
519 start with an n and gas will believe \n is ok ... */
520 .macro __BUILD_verbose nexception
521 LONG_L a1, PT_EPC(sp)
522#ifdef CONFIG_32BIT
523 ASM_PRINT("Got \nexception at %08lx\012")
524#endif
525#ifdef CONFIG_64BIT
526 ASM_PRINT("Got \nexception at %016lx\012")
527#endif
528 .endm
529
530 .macro __BUILD_count exception
531 LONG_L t0,exception_count_\exception
532 LONG_ADDIU t0, 1
533 LONG_S t0,exception_count_\exception
534 .comm exception_count\exception, 8, 8
535 .endm
536
537 .macro __BUILD_HANDLER exception handler clear verbose ext
538 .align 5
539 NESTED(handle_\exception, PT_SIZE, sp)
540 .cfi_signal_frame
541 .set noat
542 SAVE_ALL
543 FEXPORT(handle_\exception\ext)
544 __build_clear_\clear
545 .set at
546 __BUILD_\verbose \exception
547 move a0, sp
548 jal do_\handler
549 j ret_from_exception
550 END(handle_\exception)
551 .endm
552
553 .macro BUILD_HANDLER exception handler clear verbose
554 __BUILD_HANDLER \exception \handler \clear \verbose _int
555 .endm
556
557 BUILD_HANDLER adel ade ade silent /* #4 */
558 BUILD_HANDLER ades ade ade silent /* #5 */
559 BUILD_HANDLER ibe be cli silent /* #6 */
560 BUILD_HANDLER dbe be cli silent /* #7 */
561 BUILD_HANDLER bp bp sti silent /* #9 */
562 BUILD_HANDLER ri ri sti silent /* #10 */
563 BUILD_HANDLER cpu cpu sti silent /* #11 */
564 BUILD_HANDLER ov ov sti silent /* #12 */
565 BUILD_HANDLER tr tr sti silent /* #13 */
566 BUILD_HANDLER msa_fpe msa_fpe msa_fpe silent /* #14 */
567#ifdef CONFIG_MIPS_FP_SUPPORT
568 BUILD_HANDLER fpe fpe fpe silent /* #15 */
569#endif
570 BUILD_HANDLER ftlb ftlb none silent /* #16 */
571 BUILD_HANDLER gsexc gsexc gsexc silent /* #16 */
572 BUILD_HANDLER msa msa sti silent /* #21 */
573 BUILD_HANDLER mdmx mdmx sti silent /* #22 */
574#ifdef CONFIG_HARDWARE_WATCHPOINTS
575 /*
576 * For watch, interrupts will be enabled after the watch
577 * registers are read.
578 */
579 BUILD_HANDLER watch watch cli silent /* #23 */
580#else
581 BUILD_HANDLER watch watch sti verbose /* #23 */
582#endif
583 BUILD_HANDLER mcheck mcheck cli verbose /* #24 */
584 BUILD_HANDLER mt mt sti silent /* #25 */
585 BUILD_HANDLER dsp dsp sti silent /* #26 */
586 BUILD_HANDLER reserved reserved sti verbose /* others */
587
588 .align 5
589 LEAF(handle_ri_rdhwr_tlbp)
590 .set push
591 .set noat
592 .set noreorder
593 /* check if TLB contains a entry for EPC */
594 MFC0 k1, CP0_ENTRYHI
595 andi k1, MIPS_ENTRYHI_ASID | MIPS_ENTRYHI_ASIDX
596 MFC0 k0, CP0_EPC
597 PTR_SRL k0, _PAGE_SHIFT + 1
598 PTR_SLL k0, _PAGE_SHIFT + 1
599 or k1, k0
600 MTC0 k1, CP0_ENTRYHI
601 mtc0_tlbw_hazard
602 tlbp
603 tlb_probe_hazard
604 mfc0 k1, CP0_INDEX
605 .set pop
606 bltz k1, handle_ri /* slow path */
607 /* fall thru */
608 END(handle_ri_rdhwr_tlbp)
609
610 LEAF(handle_ri_rdhwr)
611 .set push
612 .set noat
613 .set noreorder
614 /* MIPS32: 0x7c03e83b: rdhwr v1,$29 */
615 /* microMIPS: 0x007d6b3c: rdhwr v1,$29 */
616 MFC0 k1, CP0_EPC
617#if defined(CONFIG_CPU_MICROMIPS) || defined(CONFIG_CPU_MIPS32_R2) || defined(CONFIG_CPU_MIPS64_R2)
618 and k0, k1, 1
619 beqz k0, 1f
620 xor k1, k0
621 lhu k0, (k1)
622 lhu k1, 2(k1)
623 ins k1, k0, 16, 16
624 lui k0, 0x007d
625 b docheck
626 ori k0, 0x6b3c
6271:
628 lui k0, 0x7c03
629 lw k1, (k1)
630 ori k0, 0xe83b
631#else
632 andi k0, k1, 1
633 bnez k0, handle_ri
634 lui k0, 0x7c03
635 lw k1, (k1)
636 ori k0, 0xe83b
637#endif
638 .set reorder
639docheck:
640 bne k0, k1, handle_ri /* if not ours */
641
642isrdhwr:
643 /* The insn is rdhwr. No need to check CAUSE.BD here. */
644 get_saved_sp /* k1 := current_thread_info */
645 .set noreorder
646 MFC0 k0, CP0_EPC
647#if defined(CONFIG_CPU_R3000)
648 ori k1, _THREAD_MASK
649 xori k1, _THREAD_MASK
650 LONG_L v1, TI_TP_VALUE(k1)
651 LONG_ADDIU k0, 4
652 jr k0
653 rfe
654#else
655#ifndef CONFIG_CPU_DADDI_WORKAROUNDS
656 LONG_ADDIU k0, 4 /* stall on $k0 */
657#else
658 .set at=v1
659 LONG_ADDIU k0, 4
660 .set noat
661#endif
662 MTC0 k0, CP0_EPC
663 /* I hope three instructions between MTC0 and ERET are enough... */
664 ori k1, _THREAD_MASK
665 xori k1, _THREAD_MASK
666 LONG_L v1, TI_TP_VALUE(k1)
667 .set push
668 .set arch=r4000
669 eret
670 .set pop
671#endif
672 .set pop
673 END(handle_ri_rdhwr)
674
675#ifdef CONFIG_CPU_R4X00_BUGS64
676/* A temporary overflow handler used by check_daddi(). */
677
678 __INIT
679
680 BUILD_HANDLER daddi_ov daddi_ov none silent /* #12 */
681#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 .cfi_signal_frame
154#ifdef CONFIG_TRACE_IRQFLAGS
155 /*
156 * Check to see if the interrupted code has just disabled
157 * interrupts and ignore this interrupt for now if so.
158 *
159 * local_irq_disable() disables interrupts and then calls
160 * trace_hardirqs_off() to track the state. If an interrupt is taken
161 * after interrupts are disabled but before the state is updated
162 * it will appear to restore_all that it is incorrectly returning with
163 * interrupts disabled
164 */
165 .set push
166 .set noat
167 mfc0 k0, CP0_STATUS
168#if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)
169 and k0, ST0_IEP
170 bnez k0, 1f
171
172 mfc0 k0, CP0_EPC
173 .set noreorder
174 j k0
175 rfe
176#else
177 and k0, ST0_IE
178 bnez k0, 1f
179
180 eret
181#endif
1821:
183 .set pop
184#endif
185 SAVE_ALL docfi=1
186 CLI
187 TRACE_IRQS_OFF
188
189 LONG_L s0, TI_REGS($28)
190 LONG_S sp, TI_REGS($28)
191
192 /*
193 * SAVE_ALL ensures we are using a valid kernel stack for the thread.
194 * Check if we are already using the IRQ stack.
195 */
196 move s1, sp # Preserve the sp
197
198 /* Get IRQ stack for this CPU */
199 ASM_CPUID_MFC0 k0, ASM_SMP_CPUID_REG
200#if defined(CONFIG_32BIT) || defined(KBUILD_64BIT_SYM32)
201 lui k1, %hi(irq_stack)
202#else
203 lui k1, %highest(irq_stack)
204 daddiu k1, %higher(irq_stack)
205 dsll k1, 16
206 daddiu k1, %hi(irq_stack)
207 dsll k1, 16
208#endif
209 LONG_SRL k0, SMP_CPUID_PTRSHIFT
210 LONG_ADDU k1, k0
211 LONG_L t0, %lo(irq_stack)(k1)
212
213 # Check if already on IRQ stack
214 PTR_LI t1, ~(_THREAD_SIZE-1)
215 and t1, t1, sp
216 beq t0, t1, 2f
217
218 /* Switch to IRQ stack */
219 li t1, _IRQ_STACK_START
220 PTR_ADD sp, t0, t1
221
222 /* Save task's sp on IRQ stack so that unwinding can follow it */
223 LONG_S s1, 0(sp)
2242:
225 jal plat_irq_dispatch
226
227 /* Restore sp */
228 move sp, s1
229
230 j ret_from_irq
231#ifdef CONFIG_CPU_MICROMIPS
232 nop
233#endif
234 END(handle_int)
235
236 __INIT
237
238/*
239 * Special interrupt vector for MIPS64 ISA & embedded MIPS processors.
240 * This is a dedicated interrupt exception vector which reduces the
241 * interrupt processing overhead. The jump instruction will be replaced
242 * at the initialization time.
243 *
244 * Be careful when changing this, it has to be at most 128 bytes
245 * to fit into space reserved for the exception handler.
246 */
247NESTED(except_vec4, 0, sp)
2481: j 1b /* Dummy, will be replaced */
249 END(except_vec4)
250
251/*
252 * EJTAG debug exception handler.
253 * The EJTAG debug exception entry point is 0xbfc00480, which
254 * normally is in the boot PROM, so the boot PROM must do an
255 * unconditional jump to this vector.
256 */
257NESTED(except_vec_ejtag_debug, 0, sp)
258 j ejtag_debug_handler
259#ifdef CONFIG_CPU_MICROMIPS
260 nop
261#endif
262 END(except_vec_ejtag_debug)
263
264 __FINIT
265
266/*
267 * Vectored interrupt handler.
268 * This prototype is copied to ebase + n*IntCtl.VS and patched
269 * to invoke the handler
270 */
271BUILD_ROLLBACK_PROLOGUE except_vec_vi
272NESTED(except_vec_vi, 0, sp)
273 SAVE_SOME docfi=1
274 SAVE_AT docfi=1
275 .set push
276 .set noreorder
277 PTR_LA v1, except_vec_vi_handler
278FEXPORT(except_vec_vi_lui)
279 lui v0, 0 /* Patched */
280 jr v1
281FEXPORT(except_vec_vi_ori)
282 ori v0, 0 /* Patched */
283 .set pop
284 END(except_vec_vi)
285EXPORT(except_vec_vi_end)
286
287/*
288 * Common Vectored Interrupt code
289 * Complete the register saves and invoke the handler which is passed in $v0
290 */
291NESTED(except_vec_vi_handler, 0, sp)
292 SAVE_TEMP
293 SAVE_STATIC
294 CLI
295#ifdef CONFIG_TRACE_IRQFLAGS
296 move s0, v0
297 TRACE_IRQS_OFF
298 move v0, s0
299#endif
300
301 LONG_L s0, TI_REGS($28)
302 LONG_S sp, TI_REGS($28)
303
304 /*
305 * SAVE_ALL ensures we are using a valid kernel stack for the thread.
306 * Check if we are already using the IRQ stack.
307 */
308 move s1, sp # Preserve the sp
309
310 /* Get IRQ stack for this CPU */
311 ASM_CPUID_MFC0 k0, ASM_SMP_CPUID_REG
312#if defined(CONFIG_32BIT) || defined(KBUILD_64BIT_SYM32)
313 lui k1, %hi(irq_stack)
314#else
315 lui k1, %highest(irq_stack)
316 daddiu k1, %higher(irq_stack)
317 dsll k1, 16
318 daddiu k1, %hi(irq_stack)
319 dsll k1, 16
320#endif
321 LONG_SRL k0, SMP_CPUID_PTRSHIFT
322 LONG_ADDU k1, k0
323 LONG_L t0, %lo(irq_stack)(k1)
324
325 # Check if already on IRQ stack
326 PTR_LI t1, ~(_THREAD_SIZE-1)
327 and t1, t1, sp
328 beq t0, t1, 2f
329
330 /* Switch to IRQ stack */
331 li t1, _IRQ_STACK_START
332 PTR_ADD sp, t0, t1
333
334 /* Save task's sp on IRQ stack so that unwinding can follow it */
335 LONG_S s1, 0(sp)
3362:
337 jalr v0
338
339 /* Restore sp */
340 move sp, s1
341
342 j ret_from_irq
343 END(except_vec_vi_handler)
344
345/*
346 * EJTAG debug exception handler.
347 */
348NESTED(ejtag_debug_handler, PT_SIZE, sp)
349 .set push
350 .set noat
351 MTC0 k0, CP0_DESAVE
352 mfc0 k0, CP0_DEBUG
353
354 sll k0, k0, 30 # Check for SDBBP.
355 bgez k0, ejtag_return
356
357 PTR_LA k0, ejtag_debug_buffer
358 LONG_S k1, 0(k0)
359 SAVE_ALL
360 move a0, sp
361 jal ejtag_exception_handler
362 RESTORE_ALL
363 PTR_LA k0, ejtag_debug_buffer
364 LONG_L k1, 0(k0)
365
366ejtag_return:
367 MFC0 k0, CP0_DESAVE
368 .set mips32
369 deret
370 .set pop
371 END(ejtag_debug_handler)
372
373/*
374 * This buffer is reserved for the use of the EJTAG debug
375 * handler.
376 */
377 .data
378EXPORT(ejtag_debug_buffer)
379 .fill LONGSIZE
380 .previous
381
382 __INIT
383
384/*
385 * NMI debug exception handler for MIPS reference boards.
386 * The NMI debug exception entry point is 0xbfc00000, which
387 * normally is in the boot PROM, so the boot PROM must do a
388 * unconditional jump to this vector.
389 */
390NESTED(except_vec_nmi, 0, sp)
391 j nmi_handler
392#ifdef CONFIG_CPU_MICROMIPS
393 nop
394#endif
395 END(except_vec_nmi)
396
397 __FINIT
398
399NESTED(nmi_handler, PT_SIZE, sp)
400 .cfi_signal_frame
401 .set push
402 .set noat
403 /*
404 * Clear ERL - restore segment mapping
405 * Clear BEV - required for page fault exception handler to work
406 */
407 mfc0 k0, CP0_STATUS
408 ori k0, k0, ST0_EXL
409 li k1, ~(ST0_BEV | ST0_ERL)
410 and k0, k0, k1
411 mtc0 k0, CP0_STATUS
412 _ehb
413 SAVE_ALL
414 move a0, sp
415 jal nmi_exception_handler
416 /* nmi_exception_handler never returns */
417 .set pop
418 END(nmi_handler)
419
420 .macro __build_clear_none
421 .endm
422
423 .macro __build_clear_sti
424 TRACE_IRQS_ON
425 STI
426 .endm
427
428 .macro __build_clear_cli
429 CLI
430 TRACE_IRQS_OFF
431 .endm
432
433 .macro __build_clear_fpe
434 .set push
435 /* gas fails to assemble cfc1 for some archs (octeon).*/ \
436 .set mips1
437 SET_HARDFLOAT
438 cfc1 a1, fcr31
439 .set pop
440 CLI
441 TRACE_IRQS_OFF
442 .endm
443
444 .macro __build_clear_msa_fpe
445 _cfcmsa a1, MSA_CSR
446 CLI
447 TRACE_IRQS_OFF
448 .endm
449
450 .macro __build_clear_ade
451 MFC0 t0, CP0_BADVADDR
452 PTR_S t0, PT_BVADDR(sp)
453 KMODE
454 .endm
455
456 .macro __BUILD_silent exception
457 .endm
458
459 /* Gas tries to parse the PRINT argument as a string containing
460 string escapes and emits bogus warnings if it believes to
461 recognize an unknown escape code. So make the arguments
462 start with an n and gas will believe \n is ok ... */
463 .macro __BUILD_verbose nexception
464 LONG_L a1, PT_EPC(sp)
465#ifdef CONFIG_32BIT
466 PRINT("Got \nexception at %08lx\012")
467#endif
468#ifdef CONFIG_64BIT
469 PRINT("Got \nexception at %016lx\012")
470#endif
471 .endm
472
473 .macro __BUILD_count exception
474 LONG_L t0,exception_count_\exception
475 LONG_ADDIU t0, 1
476 LONG_S t0,exception_count_\exception
477 .comm exception_count\exception, 8, 8
478 .endm
479
480 .macro __BUILD_HANDLER exception handler clear verbose ext
481 .align 5
482 NESTED(handle_\exception, PT_SIZE, sp)
483 .cfi_signal_frame
484 .set noat
485 SAVE_ALL
486 FEXPORT(handle_\exception\ext)
487 __build_clear_\clear
488 .set at
489 __BUILD_\verbose \exception
490 move a0, sp
491 jal do_\handler
492 j ret_from_exception
493 END(handle_\exception)
494 .endm
495
496 .macro BUILD_HANDLER exception handler clear verbose
497 __BUILD_HANDLER \exception \handler \clear \verbose _int
498 .endm
499
500 BUILD_HANDLER adel ade ade silent /* #4 */
501 BUILD_HANDLER ades ade ade silent /* #5 */
502 BUILD_HANDLER ibe be cli silent /* #6 */
503 BUILD_HANDLER dbe be cli silent /* #7 */
504 BUILD_HANDLER bp bp sti silent /* #9 */
505 BUILD_HANDLER ri ri sti silent /* #10 */
506 BUILD_HANDLER cpu cpu sti silent /* #11 */
507 BUILD_HANDLER ov ov sti silent /* #12 */
508 BUILD_HANDLER tr tr sti silent /* #13 */
509 BUILD_HANDLER msa_fpe msa_fpe msa_fpe silent /* #14 */
510 BUILD_HANDLER fpe fpe fpe silent /* #15 */
511 BUILD_HANDLER ftlb ftlb none silent /* #16 */
512 BUILD_HANDLER msa msa sti silent /* #21 */
513 BUILD_HANDLER mdmx mdmx sti silent /* #22 */
514#ifdef CONFIG_HARDWARE_WATCHPOINTS
515 /*
516 * For watch, interrupts will be enabled after the watch
517 * registers are read.
518 */
519 BUILD_HANDLER watch watch cli silent /* #23 */
520#else
521 BUILD_HANDLER watch watch sti verbose /* #23 */
522#endif
523 BUILD_HANDLER mcheck mcheck cli verbose /* #24 */
524 BUILD_HANDLER mt mt sti silent /* #25 */
525 BUILD_HANDLER dsp dsp sti silent /* #26 */
526 BUILD_HANDLER reserved reserved sti verbose /* others */
527
528 .align 5
529 LEAF(handle_ri_rdhwr_tlbp)
530 .set push
531 .set noat
532 .set noreorder
533 /* check if TLB contains a entry for EPC */
534 MFC0 k1, CP0_ENTRYHI
535 andi k1, MIPS_ENTRYHI_ASID | MIPS_ENTRYHI_ASIDX
536 MFC0 k0, CP0_EPC
537 PTR_SRL k0, _PAGE_SHIFT + 1
538 PTR_SLL k0, _PAGE_SHIFT + 1
539 or k1, k0
540 MTC0 k1, CP0_ENTRYHI
541 mtc0_tlbw_hazard
542 tlbp
543 tlb_probe_hazard
544 mfc0 k1, CP0_INDEX
545 .set pop
546 bltz k1, handle_ri /* slow path */
547 /* fall thru */
548 END(handle_ri_rdhwr_tlbp)
549
550 LEAF(handle_ri_rdhwr)
551 .set push
552 .set noat
553 .set noreorder
554 /* MIPS32: 0x7c03e83b: rdhwr v1,$29 */
555 /* microMIPS: 0x007d6b3c: rdhwr v1,$29 */
556 MFC0 k1, CP0_EPC
557#if defined(CONFIG_CPU_MICROMIPS) || defined(CONFIG_CPU_MIPS32_R2) || defined(CONFIG_CPU_MIPS64_R2)
558 and k0, k1, 1
559 beqz k0, 1f
560 xor k1, k0
561 lhu k0, (k1)
562 lhu k1, 2(k1)
563 ins k1, k0, 16, 16
564 lui k0, 0x007d
565 b docheck
566 ori k0, 0x6b3c
5671:
568 lui k0, 0x7c03
569 lw k1, (k1)
570 ori k0, 0xe83b
571#else
572 andi k0, k1, 1
573 bnez k0, handle_ri
574 lui k0, 0x7c03
575 lw k1, (k1)
576 ori k0, 0xe83b
577#endif
578 .set reorder
579docheck:
580 bne k0, k1, handle_ri /* if not ours */
581
582isrdhwr:
583 /* The insn is rdhwr. No need to check CAUSE.BD here. */
584 get_saved_sp /* k1 := current_thread_info */
585 .set noreorder
586 MFC0 k0, CP0_EPC
587#if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)
588 ori k1, _THREAD_MASK
589 xori k1, _THREAD_MASK
590 LONG_L v1, TI_TP_VALUE(k1)
591 LONG_ADDIU k0, 4
592 jr k0
593 rfe
594#else
595#ifndef CONFIG_CPU_DADDI_WORKAROUNDS
596 LONG_ADDIU k0, 4 /* stall on $k0 */
597#else
598 .set at=v1
599 LONG_ADDIU k0, 4
600 .set noat
601#endif
602 MTC0 k0, CP0_EPC
603 /* I hope three instructions between MTC0 and ERET are enough... */
604 ori k1, _THREAD_MASK
605 xori k1, _THREAD_MASK
606 LONG_L v1, TI_TP_VALUE(k1)
607 .set arch=r4000
608 eret
609 .set mips0
610#endif
611 .set pop
612 END(handle_ri_rdhwr)
613
614#ifdef CONFIG_64BIT
615/* A temporary overflow handler used by check_daddi(). */
616
617 __INIT
618
619 BUILD_HANDLER daddi_ov daddi_ov none silent /* #12 */
620#endif