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v6.2
  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
v3.15
  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#ifdef CONFIG_MIPS_MT_SMTC
 25#define PANIC_PIC(msg)					\
 26		.set	push;				\
 27		.set	nomicromips;			\
 28		.set	reorder;			\
 29		PTR_LA	a0,8f;				\
 30		.set	noat;				\
 31		PTR_LA	AT, panic;			\
 32		jr	AT;				\
 339:		b	9b;				\
 34		.set	pop;				\
 35		TEXT(msg)
 36#endif
 37
 38	__INIT
 39
 40/*
 41 * General exception vector for all other CPUs.
 42 *
 43 * Be careful when changing this, it has to be at most 128 bytes
 44 * to fit into space reserved for the exception handler.
 45 */
 46NESTED(except_vec3_generic, 0, sp)
 47	.set	push
 48	.set	noat
 49#if R5432_CP0_INTERRUPT_WAR
 50	mfc0	k0, CP0_INDEX
 51#endif
 52	mfc0	k1, CP0_CAUSE
 53	andi	k1, k1, 0x7c
 54#ifdef CONFIG_64BIT
 55	dsll	k1, k1, 1
 56#endif
 57	PTR_L	k0, exception_handlers(k1)
 58	jr	k0
 59	.set	pop
 60	END(except_vec3_generic)
 61
 62/*
 63 * General exception handler for CPUs with virtual coherency exception.
 64 *
 65 * Be careful when changing this, it has to be at most 256 (as a special
 66 * exception) bytes to fit into space reserved for the exception handler.
 67 */
 68NESTED(except_vec3_r4000, 0, sp)
 69	.set	push
 70	.set	arch=r4000
 71	.set	noat
 72	mfc0	k1, CP0_CAUSE
 73	li	k0, 31<<2
 74	andi	k1, k1, 0x7c
 75	.set	push
 76	.set	noreorder
 77	.set	nomacro
 78	beq	k1, k0, handle_vced
 79	 li	k0, 14<<2
 80	beq	k1, k0, handle_vcei
 81#ifdef CONFIG_64BIT
 82	 dsll	k1, k1, 1
 83#endif
 84	.set	pop
 85	PTR_L	k0, exception_handlers(k1)
 86	jr	k0
 87
 88	/*
 89	 * Big shit, we now may have two dirty primary cache lines for the same
 90	 * physical address.  We can safely invalidate the line pointed to by
 91	 * c0_badvaddr because after return from this exception handler the
 92	 * load / store will be re-executed.
 93	 */
 94handle_vced:
 95	MFC0	k0, CP0_BADVADDR
 96	li	k1, -4					# Is this ...
 97	and	k0, k1					# ... really needed?
 98	mtc0	zero, CP0_TAGLO
 99	cache	Index_Store_Tag_D, (k0)
100	cache	Hit_Writeback_Inv_SD, (k0)
101#ifdef CONFIG_PROC_FS
102	PTR_LA	k0, vced_count
103	lw	k1, (k0)
104	addiu	k1, 1
105	sw	k1, (k0)
106#endif
107	eret
108
109handle_vcei:
110	MFC0	k0, CP0_BADVADDR
111	cache	Hit_Writeback_Inv_SD, (k0)		# also cleans pi
112#ifdef CONFIG_PROC_FS
113	PTR_LA	k0, vcei_count
114	lw	k1, (k0)
115	addiu	k1, 1
116	sw	k1, (k0)
117#endif
118	eret
119	.set	pop
120	END(except_vec3_r4000)
121
122	__FINIT
123
124	.align	5	/* 32 byte rollback region */
125LEAF(__r4k_wait)
126	.set	push
127	.set	noreorder
128	/* start of rollback region */
129	LONG_L	t0, TI_FLAGS($28)
130	nop
131	andi	t0, _TIF_NEED_RESCHED
132	bnez	t0, 1f
133	 nop
134	nop
135	nop
136#ifdef CONFIG_CPU_MICROMIPS
137	nop
138	nop
139	nop
140	nop
141#endif
142	.set	arch=r4000
143	wait
144	/* end of rollback region (the region size must be power of two) */
1451:
146	jr	ra
147	nop
148	.set	pop
149	END(__r4k_wait)
150
151	.macro	BUILD_ROLLBACK_PROLOGUE handler
152	FEXPORT(rollback_\handler)
153	.set	push
154	.set	noat
155	MFC0	k0, CP0_EPC
156	PTR_LA	k1, __r4k_wait
157	ori	k0, 0x1f	/* 32 byte rollback region */
158	xori	k0, 0x1f
159	bne	k0, k1, 9f
160	MTC0	k0, CP0_EPC
1619:
162	.set pop
163	.endm
164
165	.align	5
166BUILD_ROLLBACK_PROLOGUE handle_int
167NESTED(handle_int, PT_SIZE, sp)
 
168#ifdef CONFIG_TRACE_IRQFLAGS
169	/*
170	 * Check to see if the interrupted code has just disabled
171	 * interrupts and ignore this interrupt for now if so.
172	 *
173	 * local_irq_disable() disables interrupts and then calls
174	 * trace_hardirqs_off() to track the state. If an interrupt is taken
175	 * after interrupts are disabled but before the state is updated
176	 * it will appear to restore_all that it is incorrectly returning with
177	 * interrupts disabled
178	 */
179	.set	push
180	.set	noat
181	mfc0	k0, CP0_STATUS
182#if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)
183	and	k0, ST0_IEP
184	bnez	k0, 1f
185
186	mfc0	k0, CP0_EPC
187	.set	noreorder
188	j	k0
189	rfe
190#else
191	and	k0, ST0_IE
192	bnez	k0, 1f
193
194	eret
195#endif
1961:
197	.set pop
198#endif
199	SAVE_ALL
200	CLI
201	TRACE_IRQS_OFF
202
203	LONG_L	s0, TI_REGS($28)
204	LONG_S	sp, TI_REGS($28)
205	PTR_LA	ra, ret_from_irq
206	PTR_LA  v0, plat_irq_dispatch
207	jr	v0
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
208#ifdef CONFIG_CPU_MICROMIPS
209	nop
210#endif
211	END(handle_int)
212
213	__INIT
214
215/*
216 * Special interrupt vector for MIPS64 ISA & embedded MIPS processors.
217 * This is a dedicated interrupt exception vector which reduces the
218 * interrupt processing overhead.  The jump instruction will be replaced
219 * at the initialization time.
220 *
221 * Be careful when changing this, it has to be at most 128 bytes
222 * to fit into space reserved for the exception handler.
223 */
224NESTED(except_vec4, 0, sp)
2251:	j	1b			/* Dummy, will be replaced */
226	END(except_vec4)
227
228/*
229 * EJTAG debug exception handler.
230 * The EJTAG debug exception entry point is 0xbfc00480, which
231 * normally is in the boot PROM, so the boot PROM must do an
232 * unconditional jump to this vector.
233 */
234NESTED(except_vec_ejtag_debug, 0, sp)
235	j	ejtag_debug_handler
236#ifdef CONFIG_CPU_MICROMIPS
237	 nop
238#endif
239	END(except_vec_ejtag_debug)
240
241	__FINIT
242
243/*
244 * Vectored interrupt handler.
245 * This prototype is copied to ebase + n*IntCtl.VS and patched
246 * to invoke the handler
247 */
248BUILD_ROLLBACK_PROLOGUE except_vec_vi
249NESTED(except_vec_vi, 0, sp)
250	SAVE_SOME
251	SAVE_AT
252	.set	push
253	.set	noreorder
254#ifdef CONFIG_MIPS_MT_SMTC
255	/*
256	 * To keep from blindly blocking *all* interrupts
257	 * during service by SMTC kernel, we also want to
258	 * pass the IM value to be cleared.
259	 */
260FEXPORT(except_vec_vi_mori)
261	ori	a0, $0, 0
262#endif /* CONFIG_MIPS_MT_SMTC */
263	PTR_LA	v1, except_vec_vi_handler
264FEXPORT(except_vec_vi_lui)
265	lui	v0, 0		/* Patched */
266	jr	v1
267FEXPORT(except_vec_vi_ori)
268	 ori	v0, 0		/* Patched */
269	.set	pop
270	END(except_vec_vi)
271EXPORT(except_vec_vi_end)
272
273/*
274 * Common Vectored Interrupt code
275 * Complete the register saves and invoke the handler which is passed in $v0
276 */
277NESTED(except_vec_vi_handler, 0, sp)
278	SAVE_TEMP
279	SAVE_STATIC
280#ifdef CONFIG_MIPS_MT_SMTC
281	/*
282	 * SMTC has an interesting problem that interrupts are level-triggered,
283	 * and the CLI macro will clear EXL, potentially causing a duplicate
284	 * interrupt service invocation. So we need to clear the associated
285	 * IM bit of Status prior to doing CLI, and restore it after the
286	 * service routine has been invoked - we must assume that the
287	 * service routine will have cleared the state, and any active
288	 * level represents a new or otherwised unserviced event...
289	 */
290	mfc0	t1, CP0_STATUS
291	and	t0, a0, t1
292#ifdef CONFIG_MIPS_MT_SMTC_IM_BACKSTOP
293	mfc0	t2, CP0_TCCONTEXT
294	or	t2, t0, t2
295	mtc0	t2, CP0_TCCONTEXT
296#endif /* CONFIG_MIPS_MT_SMTC_IM_BACKSTOP */
297	xor	t1, t1, t0
298	mtc0	t1, CP0_STATUS
299	_ehb
300#endif /* CONFIG_MIPS_MT_SMTC */
301	CLI
302#ifdef CONFIG_TRACE_IRQFLAGS
303	move	s0, v0
304#ifdef CONFIG_MIPS_MT_SMTC
305	move	s1, a0
306#endif
307	TRACE_IRQS_OFF
308#ifdef CONFIG_MIPS_MT_SMTC
309	move	a0, s1
310#endif
311	move	v0, s0
312#endif
313
314	LONG_L	s0, TI_REGS($28)
315	LONG_S	sp, TI_REGS($28)
316	PTR_LA	ra, ret_from_irq
317	jr	v0
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
318	END(except_vec_vi_handler)
319
320/*
321 * EJTAG debug exception handler.
322 */
323NESTED(ejtag_debug_handler, PT_SIZE, sp)
324	.set	push
325	.set	noat
326	MTC0	k0, CP0_DESAVE
327	mfc0	k0, CP0_DEBUG
328
329	sll	k0, k0, 30	# Check for SDBBP.
330	bgez	k0, ejtag_return
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
331
 
 
 
332	PTR_LA	k0, ejtag_debug_buffer
333	LONG_S	k1, 0(k0)
 
 
334	SAVE_ALL
335	move	a0, sp
336	jal	ejtag_exception_handler
337	RESTORE_ALL
 
 
 
 
 
 
 
 
 
338	PTR_LA	k0, ejtag_debug_buffer
339	LONG_L	k1, 0(k0)
 
340
341ejtag_return:
 
342	MFC0	k0, CP0_DESAVE
343	.set	mips32
344	deret
345	.set pop
346	END(ejtag_debug_handler)
347
348/*
349 * This buffer is reserved for the use of the EJTAG debug
350 * handler.
351 */
352	.data
353EXPORT(ejtag_debug_buffer)
354	.fill	LONGSIZE
 
 
 
 
 
 
355	.previous
356
357	__INIT
358
359/*
360 * NMI debug exception handler for MIPS reference boards.
361 * The NMI debug exception entry point is 0xbfc00000, which
362 * normally is in the boot PROM, so the boot PROM must do a
363 * unconditional jump to this vector.
364 */
365NESTED(except_vec_nmi, 0, sp)
366	j	nmi_handler
367#ifdef CONFIG_CPU_MICROMIPS
368	 nop
369#endif
370	END(except_vec_nmi)
371
372	__FINIT
373
374NESTED(nmi_handler, PT_SIZE, sp)
 
375	.set	push
376	.set	noat
377	/*
378	 * Clear ERL - restore segment mapping
379	 * Clear BEV - required for page fault exception handler to work
380	 */
381	mfc0	k0, CP0_STATUS
382	ori     k0, k0, ST0_EXL
383	li	k1, ~(ST0_BEV | ST0_ERL)
384	and     k0, k0, k1
385	mtc0    k0, CP0_STATUS
386	_ehb
387	SAVE_ALL
388	move	a0, sp
389	jal	nmi_exception_handler
390	/* nmi_exception_handler never returns */
391	.set	pop
392	END(nmi_handler)
393
394	.macro	__build_clear_none
395	.endm
396
397	.macro	__build_clear_sti
398	TRACE_IRQS_ON
399	STI
400	.endm
401
402	.macro	__build_clear_cli
403	CLI
404	TRACE_IRQS_OFF
405	.endm
406
407	.macro	__build_clear_fpe
 
 
408	.set	push
409	/* gas fails to assemble cfc1 for some archs (octeon).*/ \
410	.set	mips1
 
411	cfc1	a1, fcr31
412	li	a2, ~(0x3f << 12)
413	and	a2, a1
414	ctc1	a2, fcr31
415	.set	pop
416	TRACE_IRQS_ON
417	STI
 
 
 
 
418	.endm
419
420	.macro	__build_clear_ade
421	MFC0	t0, CP0_BADVADDR
422	PTR_S	t0, PT_BVADDR(sp)
423	KMODE
424	.endm
425
 
 
 
 
 
 
 
 
 
 
 
 
 
426	.macro	__BUILD_silent exception
427	.endm
428
429	/* Gas tries to parse the PRINT argument as a string containing
430	   string escapes and emits bogus warnings if it believes to
431	   recognize an unknown escape code.  So make the arguments
432	   start with an n and gas will believe \n is ok ...  */
433	.macro	__BUILD_verbose nexception
434	LONG_L	a1, PT_EPC(sp)
435#ifdef CONFIG_32BIT
436	PRINT("Got \nexception at %08lx\012")
437#endif
438#ifdef CONFIG_64BIT
439	PRINT("Got \nexception at %016lx\012")
440#endif
441	.endm
442
443	.macro	__BUILD_count exception
444	LONG_L	t0,exception_count_\exception
445	LONG_ADDIU t0, 1
446	LONG_S	t0,exception_count_\exception
447	.comm	exception_count\exception, 8, 8
448	.endm
449
450	.macro	__BUILD_HANDLER exception handler clear verbose ext
451	.align	5
452	NESTED(handle_\exception, PT_SIZE, sp)
 
453	.set	noat
454	SAVE_ALL
455	FEXPORT(handle_\exception\ext)
456	__BUILD_clear_\clear
457	.set	at
458	__BUILD_\verbose \exception
459	move	a0, sp
460	PTR_LA	ra, ret_from_exception
461	j	do_\handler
462	END(handle_\exception)
463	.endm
464
465	.macro	BUILD_HANDLER exception handler clear verbose
466	__BUILD_HANDLER \exception \handler \clear \verbose _int
467	.endm
468
469	BUILD_HANDLER adel ade ade silent		/* #4  */
470	BUILD_HANDLER ades ade ade silent		/* #5  */
471	BUILD_HANDLER ibe be cli silent			/* #6  */
472	BUILD_HANDLER dbe be cli silent			/* #7  */
473	BUILD_HANDLER bp bp sti silent			/* #9  */
474	BUILD_HANDLER ri ri sti silent			/* #10 */
475	BUILD_HANDLER cpu cpu sti silent		/* #11 */
476	BUILD_HANDLER ov ov sti silent			/* #12 */
477	BUILD_HANDLER tr tr sti silent			/* #13 */
478	BUILD_HANDLER msa_fpe msa_fpe sti silent	/* #14 */
 
479	BUILD_HANDLER fpe fpe fpe silent		/* #15 */
 
480	BUILD_HANDLER ftlb ftlb none silent		/* #16 */
 
481	BUILD_HANDLER msa msa sti silent		/* #21 */
482	BUILD_HANDLER mdmx mdmx sti silent		/* #22 */
483#ifdef	CONFIG_HARDWARE_WATCHPOINTS
484	/*
485	 * For watch, interrupts will be enabled after the watch
486	 * registers are read.
487	 */
488	BUILD_HANDLER watch watch cli silent		/* #23 */
489#else
490	BUILD_HANDLER watch watch sti verbose		/* #23 */
491#endif
492	BUILD_HANDLER mcheck mcheck cli verbose		/* #24 */
493	BUILD_HANDLER mt mt sti silent			/* #25 */
494	BUILD_HANDLER dsp dsp sti silent		/* #26 */
495	BUILD_HANDLER reserved reserved sti verbose	/* others */
496
497	.align	5
498	LEAF(handle_ri_rdhwr_vivt)
499#ifdef CONFIG_MIPS_MT_SMTC
500	PANIC_PIC("handle_ri_rdhwr_vivt called")
501#else
502	.set	push
503	.set	noat
504	.set	noreorder
505	/* check if TLB contains a entry for EPC */
506	MFC0	k1, CP0_ENTRYHI
507	andi	k1, 0xff	/* ASID_MASK */
508	MFC0	k0, CP0_EPC
509	PTR_SRL k0, _PAGE_SHIFT + 1
510	PTR_SLL k0, _PAGE_SHIFT + 1
511	or	k1, k0
512	MTC0	k1, CP0_ENTRYHI
513	mtc0_tlbw_hazard
514	tlbp
515	tlb_probe_hazard
516	mfc0	k1, CP0_INDEX
517	.set	pop
518	bltz	k1, handle_ri	/* slow path */
519	/* fall thru */
520#endif
521	END(handle_ri_rdhwr_vivt)
522
523	LEAF(handle_ri_rdhwr)
524	.set	push
525	.set	noat
526	.set	noreorder
527	/* MIPS32:    0x7c03e83b: rdhwr v1,$29 */
528	/* microMIPS: 0x007d6b3c: rdhwr v1,$29 */
529	MFC0	k1, CP0_EPC
530#if defined(CONFIG_CPU_MICROMIPS) || defined(CONFIG_CPU_MIPS32_R2) || defined(CONFIG_CPU_MIPS64_R2)
531	and     k0, k1, 1
532	beqz    k0, 1f
533	xor     k1, k0
534	lhu     k0, (k1)
535	lhu     k1, 2(k1)
536	ins     k1, k0, 16, 16
537	lui     k0, 0x007d
538	b       docheck
539	ori     k0, 0x6b3c
5401:
541	lui     k0, 0x7c03
542	lw      k1, (k1)
543	ori     k0, 0xe83b
544#else
545	andi    k0, k1, 1
546	bnez    k0, handle_ri
547	lui     k0, 0x7c03
548	lw      k1, (k1)
549	ori     k0, 0xe83b
550#endif
551	.set    reorder
552docheck:
553	bne	k0, k1, handle_ri	/* if not ours */
554
555isrdhwr:
556	/* The insn is rdhwr.  No need to check CAUSE.BD here. */
557	get_saved_sp	/* k1 := current_thread_info */
558	.set	noreorder
559	MFC0	k0, CP0_EPC
560#if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX)
561	ori	k1, _THREAD_MASK
562	xori	k1, _THREAD_MASK
563	LONG_L	v1, TI_TP_VALUE(k1)
564	LONG_ADDIU	k0, 4
565	jr	k0
566	 rfe
567#else
568#ifndef CONFIG_CPU_DADDI_WORKAROUNDS
569	LONG_ADDIU	k0, 4		/* stall on $k0 */
570#else
571	.set	at=v1
572	LONG_ADDIU	k0, 4
573	.set	noat
574#endif
575	MTC0	k0, CP0_EPC
576	/* I hope three instructions between MTC0 and ERET are enough... */
577	ori	k1, _THREAD_MASK
578	xori	k1, _THREAD_MASK
579	LONG_L	v1, TI_TP_VALUE(k1)
 
580	.set	arch=r4000
581	eret
582	.set	mips0
583#endif
584	.set	pop
585	END(handle_ri_rdhwr)
586
587#ifdef CONFIG_64BIT
588/* A temporary overflow handler used by check_daddi(). */
589
590	__INIT
591
592	BUILD_HANDLER  daddi_ov daddi_ov none silent	/* #12 */
593#endif