xref: /netbsd-src/sys/arch/powerpc/ibm4xx/trap_subr.S (revision 46f5119e40af2e51998f686b2fdcc76b5488f7f3)
1/*	$NetBSD: trap_subr.S,v 1.14 2011/05/02 06:37:47 kiyohara Exp $	*/
2
3/*
4 * Copyright 2001 Wasabi Systems, Inc.
5 * All rights reserved.
6 *
7 * Written by Eduardo Horvath and Simon Burge for Wasabi Systems, Inc.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 3. All advertising materials mentioning features or use of this software
18 *    must display the following acknowledgement:
19 *      This product includes software developed for the NetBSD Project by
20 *      Wasabi Systems, Inc.
21 * 4. The name of Wasabi Systems, Inc. may not be used to endorse
22 *    or promote products derived from this software without specific prior
23 *    written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
27 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
28 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
29 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35 * POSSIBILITY OF SUCH DAMAGE.
36 */
37
38/*
39 * Copyright (C) 1995, 1996 Wolfgang Solfrank.
40 * Copyright (C) 1995, 1996 TooLs GmbH.
41 * All rights reserved.
42 *
43 * Redistribution and use in source and binary forms, with or without
44 * modification, are permitted provided that the following conditions
45 * are met:
46 * 1. Redistributions of source code must retain the above copyright
47 *    notice, this list of conditions and the following disclaimer.
48 * 2. Redistributions in binary form must reproduce the above copyright
49 *    notice, this list of conditions and the following disclaimer in the
50 *    documentation and/or other materials provided with the distribution.
51 * 3. All advertising materials mentioning features or use of this software
52 *    must display the following acknowledgement:
53 *	This product includes software developed by TooLs GmbH.
54 * 4. The name of TooLs GmbH may not be used to endorse or promote products
55 *    derived from this software without specific prior written permission.
56 *
57 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
58 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
59 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
60 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
61 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
62 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
63 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
64 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
65 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
66 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
67 */
68
69/*
70 * NOTICE: This is not a standalone file.  to use it, #include it in
71 * your port's locore.S, like so:
72 *
73 *	#include <powerpc/ibm4xx/trap_subr.S>
74 */
75
76/*
77 * XXX Interrupt and spill stacks need to be per-CPU.
78 */
79
80#define	GET_PCB(rX)	\
81	GET_CPUINFO(rX);	\
82	lwz	rX,CI_CURPCB(rX)
83
84#define	STANDARD_PROLOG(savearea)	\
85	mtsprg1	%r1;			/* save SP */ 		\
86	GET_CPUINFO(%r1);					\
87	stmw	%r28,(savearea+CPUSAVE_R28)(%r1); /* free r28-r31 */	\
88	mflr	%r28;			/* save LR */		\
89	mfcr	%r29;			/* save CR */		\
90	mfsrr0	%r30;						\
91	mfsrr1	%r31; /* Test whether we already had PR set */	\
92	stmw	%r30,(savearea+CPUSAVE_SRR0)(%r1); /* save srr0/srr1 */	\
93	mfsprg1	%r1;			/* restore SP */ 	\
94	mtcr	%r31;						\
95	bc	%cr4,MSR_PR,1f;	/* branch if MSR[PR] is clear */	\
96	GET_PCB(%r1);						\
97	addi	%r1,%r1,USPACE-CALLFRAMELEN; /* stack is top of user struct */ \
981:
99
100#define	ACCESS_PROLOG(savearea)					\
101	mtsprg1	%r1;			/* save SP temporalily */	\
102	GET_CPUINFO(%r1);					\
103	stmw	%r28,(savearea+CPUSAVE_R28)(%r1); /* free r28-r31 */	\
104	mflr	%r28;			/* save LR */		\
105	mfcr	%r29;			/* save CR */		\
106	mfdear	%r30;						\
107	mfesr	%r31;						\
108	stmw	%r30,(savearea+CPUSAVE_DEAR)(%r1);		\
109	mfsrr0	%r30;						\
110	mfsrr1	%r31; /* Test whether we already had PR set */	\
111	stmw	%r30,(savearea+CPUSAVE_SRR0)(%r1); /* save srr0/srr1 */	\
112	mfsprg1	%r1;			/* restore SP */ 	\
113	mtcr	%r31;						\
114	bc	%cr4,MSR_PR,1f;	/* branch if MSR[PR] is clear */	\
115	GET_PCB(%r1);						\
116	addi	%r1,%r1,USPACE-CALLFRAMELEN; /* stack is top of user struct */ \
1171:
118
119#define	CRITICAL_PROLOG(savearea)				\
120	mtsprg1	%r1;			/* save SP */ 		\
121	GET_CPUINFO(%r1);					\
122	stmw	%r28,(savearea+CPUSAVE_R28)(%r1); /* free r28-r31 */	\
123	mflr	%r28;			/* save LR */		\
124	mfcr	%r29;			/* save CR */		\
125	mfsrr2	%r30; /* Fake a standard trap */		\
126	mfsrr3	%r31; /* Test whether we already had PR set */	\
127	stmw	%r30,(savearea+CPUSAVE_SRR0)(%r1); /* save srr0/srr1 */	\
128	mfsprg1	%r1;			/* restore SP */ 	\
129	mtcr	%r31;						\
130	bc	%cr4,MSR_PR,1f;	/* branch if MSR[PR] is clear */	\
131	GET_PCB(%r1);						\
132	addi	%r1,%r1,USPACE-CALLFRAMELEN; /* stack is top of user struct */ \
1331:
134
135
136/* Standard handler saves r1,r28-31,LR,CR, sets up the stack and calls s_trap */
137#define STANDARD_EXC_HANDLER(name)\
138	.globl	_C_LABEL(name ## trap),_C_LABEL(name ## size) ;	\
139_C_LABEL(name ## trap):						\
140	STANDARD_PROLOG(CI_TEMPSAVE);				\
141	bla	s_trap  ;					\
142_C_LABEL(name ## size) = .-_C_LABEL(name ## trap)
143
144/* Access exceptions also need DEAR and ESR saved */
145#define ACCESS_EXC_HANDLER(name)\
146	.globl	_C_LABEL(name ## trap),_C_LABEL(name ## size) ;	\
147_C_LABEL(name ## trap):						\
148	ACCESS_PROLOG(CI_TEMPSAVE);				\
149	bla	s_trap  ;					\
150_C_LABEL(name ## size) = .-_C_LABEL(name ## trap)
151
152/* Maybe this should call ddb.... */
153#define CRITICAL_EXC_HANDLER(name)\
154	.globl	_C_LABEL(name ## trap),_C_LABEL(name ## size) ;	\
155_C_LABEL(name ## trap):						\
156	CRITICAL_PROLOG(CI_TEMPSAVE);				\
157	bla	s_trap  ;					\
158_C_LABEL(name ## size) = .-_C_LABEL(name ## trap)
159
160#define	INTR_PROLOG(tempsave)					\
161	mtsprg1	%r1;			/* save SP */		\
162	GET_CPUINFO(%r1);					\
163	stmw	%r28,(tempsave+CPUSAVE_R28)(%r1); /* free r28-r31 */ \
164	mflr	%r28;			/* save LR */		\
165	mfcr	%r29;			/* save CR */		\
166	mfxer	%r30;			/* save XER */		\
167	lwz	%r31,CI_IDEPTH(%r1);	/* already running on intstk? */ \
168	addic.	%r31,%r31,1;					\
169	stw	%r31,CI_IDEPTH(%r1);				\
170	lwz	%r1,CI_INTSTK(%r1);	/* get intstk */	\
171	beq	1f;						\
172	mfsprg1	%r1;			/* yes, get old SP */	\
1731:
174
175/*
176 * This code gets copied to all the trap vectors
177 * (except ISI/DSI, ALI, the interrupts, and possibly the debugging
178 * traps when using IPKDB).
179 */
180	.text
181	STANDARD_EXC_HANDLER(default)
182	ACCESS_EXC_HANDLER(ali)
183	ACCESS_EXC_HANDLER(dsi)
184	ACCESS_EXC_HANDLER(isi)
185	STANDARD_EXC_HANDLER(debug)
186	CRITICAL_EXC_HANDLER(mchk)
187
188/*
189 * This one for the external interrupt handler.
190 */
191	.globl	_C_LABEL(extint),_C_LABEL(extsize)
192_C_LABEL(extint):
193	INTR_PROLOG(CI_TEMPSAVE)
194	ba	extintr
195_C_LABEL(extsize) = .-_C_LABEL(extint)
196
197
198#if defined(DDB) || defined(KGDB)
199/*
200 * In case of DDB we want a separate trap catcher for it
201 */
202	.lcomm	ddbstk,INTSTK,16	/* ddb stack */
203
204	.globl	_C_LABEL(ddblow),_C_LABEL(ddbsize)
205_C_LABEL(ddblow):
206	mtsprg1	%r1			/* save SP */
207	GET_CPUINFO(%r1)
208	stmw	%r28,CI_DDBSAVE(%r1)	/* free r28-r31 */
209	mflr	%r28			/* save LR */
210	mfcr	%r29			/* save CR */
211	lis	%r1,ddbstk+INTSTK-CALLFRAMELEN@ha	/* get new SP */
212	addi	%r1,%r1,ddbstk+INTSTK-CALLFRAMELEN@l
213	bla	ddbtrap
214_C_LABEL(ddbsize) = .-_C_LABEL(ddblow)
215#endif	/* DDB || KGDB */
216
217#ifdef IPKDB
218/*
219 * In case of IPKDB we want a separate trap catcher for it
220 */
221
222	.lcomm	ipkdbstk,INTSTK,16	/* ipkdb stack */
223
224	.globl	_C_LABEL(ipkdblow),_C_LABEL(ipkdbsize)
225_C_LABEL(ipkdblow):
226	mtsprg1	%r1			/* save SP */
227	GET_CPUINFO(%r1)
228	stmw	%r28,CI_IPKDBSAVE(%r1)	/* free r28-r31 */
229	mflr	%r28			/* save LR */
230	mfcr	%r29			/* save CR */
231	lis	%r1,ipkdbstk+INTSTK-CALLFRAMELEN@ha	/* get new SP */
232	addi	%r1,%r1,ipkdbstk+INTSTK-CALLFRAMELEN@l
233	bla	ipkdbtrap
234_C_LABEL(ipkdbsize) = .-_C_LABEL(ipkdblow)
235#endif	/* IPKDB */
236
237#ifdef DEBUG
238#define TRAP_IF_ZERO(r)	tweqi	r,0
239#else
240#define TRAP_IF_ZERO(r)
241#endif
242
243#define	ENABLE_TRANSLATION(pidreg,tmpreg)				\
244	mfpid	pidreg;							\
245	li	tmpreg, KERNEL_PID;					\
246	mtpid	tmpreg;							\
247	mfmsr	tmpreg;							\
248	ori	tmpreg,tmpreg,(PSL_DR|PSL_IR)@l;			\
249	mtmsr	tmpreg;							\
250	isync
251
252/*
253 * FRAME_SETUP assumes:
254 *	SPRG1		SP (r1)
255 *	savearea	r28-r31,DEAR,ESR,SRR0,SRR1 (DEAR & ESR only for DSI traps)
256 *	%r28		LR
257 *	%r29		CR
258 *	%r1		kernel stack
259 *	LR		trap type
260 */
261#define	FRAME_SETUP(savearea)						\
262/* Have to enable translation to allow access of kernel stack: */	\
263	ENABLE_TRANSLATION(%r30,%r31);					\
264	mfsprg1	%r31;							\
265	stwu	%r31,-FRAMELEN(%r1);					\
266	stw	%r30,FRAME_PID(%r1);					\
267	stw	%r0,FRAME_R0(%r1);					\
268	stw	%r31,FRAME_R1(%r1);					\
269	stw	%r2,FRAME_R2(%r1);					\
270	GET_CPUINFO(%r2);						\
271	stw	%r28,FRAME_LR(%r1);					\
272	stw	%r29,FRAME_CR(%r1);					\
273	lmw	%r28,(savearea+CPUSAVE_R28)(%r2);			\
274	stmw	%r3,FRAME_R3(%r1);					\
275	lmw	%r28,(savearea+CPUSAVE_DEAR)(%r2);			\
276	mfxer	%r3;							\
277	mfctr	%r4;							\
278	mflr	%r5;							\
279	andi.	%r5,%r5,0xff00;						\
280	stw	%r3,FRAME_XER(%r1);					\
281	stw	%r4,FRAME_CTR(%r1);					\
282	stw	%r5,FRAME_EXC(%r1);					\
283	stw	%r28,FRAME_DEAR(%r1);					\
284	stw	%r29,FRAME_ESR(%r1);					\
285	stw	%r30,FRAME_SRR0(%r1);					\
286	stw	%r31,FRAME_SRR1(%r1)
287
288#define	FRAME_SAVE_CALLEE						\
289	stmw	%r13, FRAME_R13(%r1)
290
291#define	FRAME_RESTORE							\
292	lwz	%r6,FRAME_LR(%r1);					\
293	lwz	%r7,FRAME_CR(%r1);					\
294	lwz	%r8,FRAME_XER(%r1);					\
295	lwz	%r9,FRAME_CTR(%r1);					\
296	lwz	%r10,FRAME_SRR0(%r1);					\
297	lwz	%r11,FRAME_SRR1(%r1);					\
298	mtlr	%r6;							\
299	mtcr	%r7;							\
300	mtxer	%r8;							\
301	mtctr	%r9;							\
302	mtsrr0	%r10;							\
303	mtsrr1	%r11;							\
304	lwz	%r12,FRAME_R12(%r1);					\
305	lwz	%r11,FRAME_R11(%r1);					\
306	lwz	%r10,FRAME_R10(%r1);					\
307	lwz	%r9,FRAME_R9(%r1);					\
308	lwz	%r8,FRAME_R8(%r1);					\
309	lwz	%r7,FRAME_R7(%r1);					\
310	lwz	%r6,FRAME_R6(%r1);					\
311	lwz	%r5,FRAME_R5(%r1);					\
312	lwz	%r4,FRAME_R4(%r1);					\
313	lwz	%r3,FRAME_R3(%r1);					\
314	lwz	%r2,FRAME_R2(%r1);					\
315	lwz	%r0,FRAME_R1(%r1);					\
316	mtsprg1	%r0;							\
317	lwz	%r0,FRAME_R0(%r1)
318
319/*
320 * Now the common trap catching code.
321 */
322s_trap:
323	FRAME_SETUP(CI_TEMPSAVE)
324	/* R31 = SRR1 */
325/* Now we can recover interrupts again: */
326trapagain:
327	wrtee	%r31			/* reenable interrupts */
328/* Call C trap code: */
329	addi	%r3,%r1,FRAME_TF
330	bl	_C_LABEL(trap)
331	.globl	_C_LABEL(trapexit)
332_C_LABEL(trapexit):
333	/* Disable interrupts: */
334	wrteei	0
335
336	/* Test AST pending: */
337	mtcr	%r31
338	bc	%cr4,MSR_PR,trapleave_to_kernel /* branch if MSR[PR] is false */
339
340	GET_CPUINFO(%r3)
341	lwz	%r4,CI_ASTPENDING(%r3)
342	andi.	%r4,%r4,1
343	beq	trapleave_to_user
344
345	li	%r6,EXC_AST
346	stw	%r6,FRAME_EXC(%r1)
347	b	trapagain
348
349trapleave_to_kernel:
350	lmw	%r13, FRAME_R13(%r1)	/* restore callee registers */
351
352intrleave_to_kernel:
353	FRAME_RESTORE		/* old SP is now in sprg1 */
354	/*
355	 * Now that we are done with the trapframe, we can load the original SP
356	 */
357	mfsprg1	%r1
358	rfi
359	ba	.		/* Protect against prefetch */
360
361trapleave_to_user:
362	lmw	%r13, FRAME_R13(%r1)	/* restore callee registers */
363
364intrleave_to_user:
365/* Now restore regs: */
366	lwz	%r3,FRAME_PID(%r1)
367	lwz	%r4,FRAME_SRR1(%r1)
368	bl	_C_LABEL(ctx_setup)
369	TRAP_IF_ZERO(%r3)
370	stw	%r3,FRAME_PID(%r1)
371
372	FRAME_RESTORE		/* old SP is now in sprg1 */
373
374	/*
375	 * We are returning to userspace so we need to switch PIDs.
376	 * Since the kernel executes out of what would be userspace,
377	 * we need to turn off translation before we set the PID.
378	 *
379	 * Alterantively, we could map a kernel page at 0xfffff000
380	 * that had the mtpid code in it and branch to it and avoid
381	 * all this.  (ba foo; foo: mtpid %r31; mfsprg3 %r31; rfi;)
382	 */
383	mfmsr	%r30
384	li	%r31,(PSL_DR|PSL_IR)@l
385	andc	%r30,%r30,%r31
386	lwz	%r31,FRAME_PID(%r1)
387	TRAP_IF_ZERO(%r31)
388	/*
389	 * Now that we are done with the trapframe, we can load the original SP
390	 */
391	mfsprg1	%r1
392	mtmsr	%r30	/* disable translation */
393	isync
394	mtpid	%r31
395	mfsprg3	%r31
396	mfsprg2	%r30
397	rfi
398	ba	.	/* Protect against prefetch */
399
400
401	.globl	_C_LABEL(sctrap),_C_LABEL(scsize),_C_LABEL(sctrapexit)
402_C_LABEL(sctrap):
403	STANDARD_PROLOG(CI_TEMPSAVE)
404	bla	s_sctrap
405_C_LABEL(scsize) = .-_C_LABEL(sctrap)
406
407s_sctrap:
408	FRAME_SETUP(CI_TEMPSAVE)
409/* Now we can recover interrupts again: */
410	wrteei	1			/* Enable interrupts */
411/* Call the appropriate syscall handler: */
412	addi	%r3,%r1,FRAME_TF
413	GET_CPUINFO(%r4)
414	lwz	%r4,CI_CURLWP(%r4)
415	lwz	%r4,L_PROC(%r4)
416	lwz	%r4,P_MD_SYSCALL(%r4)
417	mtctr	%r4
418	bctrl
419_C_LABEL(sctrapexit):
420	b	trapexit
421
422/*
423 * External interrupt second level handler
424 */
425
426#define	INTR_SAVE(tempsave)						\
427/* Save non-volatile registers: */					\
428	stwu	%r1,-FRAMELEN(%r1);	/* temporarily */		\
429	stw	%r0,FRAME_R0(%r1);					\
430	mfsprg1	%r0;			/* get original SP */		\
431	stw	%r0,FRAME_R1(%r1);	/* and store it */		\
432	stw	%r2,FRAME_R2(%r1);					\
433	stw	%r3,FRAME_R3(%r1);					\
434	stw	%r4,FRAME_R4(%r1);					\
435	stw	%r5,FRAME_R5(%r1);					\
436	stw	%r6,FRAME_R6(%r1);					\
437	stw	%r7,FRAME_R7(%r1);					\
438	stw	%r8,FRAME_R8(%r1);					\
439	stw	%r9,FRAME_R9(%r1);					\
440	stw	%r10,FRAME_R10(%r1);					\
441	stw	%r11,FRAME_R11(%r1);					\
442	stw	%r12,FRAME_R12(%r1);					\
443	mfctr	%r31;							\
444	stmw	%r28,FRAME_LR(%r1);	/* save LR, CR, XER, CTR */	\
445	GET_CPUINFO(%r5);						\
446	lmw	%r28,(tempsave+CPUSAVE_R28)(%r5); /* restore r28-r31 */	\
447	lwz	%r5,CI_IDEPTH(%r5);					\
448	mfsrr0	%r4;							\
449	mfsrr1	%r3;							\
450	stw	%r5,FRAME_IDEPTH(%r1);					\
451	stw	%r4,FRAME_SRR0(%r1);					\
452	stw	%r3,FRAME_SRR1(%r1);					\
453/* interrupts are recoverable here, and enable translation */		\
454	ENABLE_TRANSLATION(%r0,%r5);					\
455	stw	%r0,FRAME_PID(%r1);					\
456
457	.globl	_C_LABEL(extint_call)
458extintr:
459	INTR_SAVE(CI_TEMPSAVE)
460_C_LABEL(extint_call):
461	bl	_C_LABEL(extint_call)	/* to be filled in later */
462
463intr_exit:
464/* Disable interrupts */
465	wrteei	0
466	isync
467	GET_CPUINFO(%r5)
468	lwz	%r4,CI_IDEPTH(%r5)
469	addi	%r4,%r4,-1		/* adjust reentrancy count */
470	stw	%r4,CI_IDEPTH(%r5)
471
472	lwz	%r5,FRAME_SRR1(%r1)
473/* Returning to user mode? */
474	mtcr	%r5			/* saved SRR1 */
475	bc	%cr4,MSR_PR,intrleave_to_kernel /* branch if MSR[PR] is false */
476
477	lwz	%r4,CI_ASTPENDING(%r5)	/* Test AST pending */
478	andi.	%r4,%r4,1
479	beq	intrleave_to_user
480
481	FRAME_SAVE_CALLEE		/* save rest of callee registers */
482	li	%r6,EXC_AST
483	stw	%r6,FRAME_EXC(%r1)
484	mr	%r31,%r5		/* move SRR1 to R31 */
485	b	trapagain
486
487/*
488 * PIT interrupt handler.
489 */
490	.align	5
491_C_LABEL(pitint):
492	INTR_PROLOG(CI_TEMPSAVE)
493	INTR_SAVE(CI_TEMPSAVE)
494	addi	%r3,%r1,FRAME_CF	/* intr frame */
495	bl	_C_LABEL(decr_intr)
496	b	intr_exit
497
498/*
499 * FIT interrupt handler.
500 */
501	.align	5
502_C_LABEL(fitint):
503	INTR_PROLOG(CI_TEMPSAVE)
504	INTR_SAVE(CI_TEMPSAVE)
505	addi	%r3,%r1,FRAME_TF	/* intr frame */
506	bl	_C_LABEL(stat_intr)
507	b	intr_exit
508
509#if defined(DDB) || defined(KGDB)
510/*
511 * Deliberate entry to ddbtrap
512 */
513	.globl	_C_LABEL(ddb_trap)
514_C_LABEL(ddb_trap):
515	mtsprg1	%r1
516	GET_CPUINFO(%r4)
517	mfmsr	%r3
518	stw	%r3,CI_DDBSAVE+CPUSAVE_SRR1(%r4)
519	wrteei	0			/* disable interrupts */
520	isync
521	stmw	%r28,CI_DDBSAVE(%r1)
522	mflr	%r28
523	stw	%r28,CI_DDBSAVE+CPUSAVE_SRR0(%r4)
524	li	%r29,EXC_BPT
525	mtlr	%r29
526	mfcr	%r29
527
528/*
529 * Now the ddb/kgdb trap catching code.
530 */
531ddbtrap:
532	FRAME_SETUP(CI_DDBSAVE)
533/* Call C trap code: */
534	addi	%r3,%r1,FRAME_TF
535	bl	_C_LABEL(ddb_trap_glue)
536	or.	%r3,%r3,%r3
537	addi	%r3,%r1,FRAME_TF
538	beq	trapagain
539	b	trapexit
540#endif /* DDB || KGDB */
541
542#ifdef IPKDB
543/*
544 * Deliberate entry to ipkdbtrap
545 */
546	.globl	_C_LABEL(ipkdb_trap)
547_C_LABEL(ipkdb_trap):
548	mtsprg1	%r1
549	GET_CPUINFO(%r4)
550	mfmsr	%r3
551	stw	%r3,(CI_IPKDBSAVE+CPUSAVE_SRR1)(%r4)
552	wrteei	0			/* disable interrupts */
553	isync
554	stmw	%r28,CI_IPKDBSAVE(%r4)
555	mflr	%r28
556	stw	%r28,(CI_IPKDBSAVE+CPUSAVE_SRR0)(%r4)
557	li	%r29,EXC_BPT
558	mtlr	%r29
559	mfcr	%r29
560
561/*
562 * Now the ipkdb trap catching code.
563 */
564ipkdbtrap:
565	FRAME_SETUP(CI_IPKDBSAVE)
566/* Call C trap code: */
567	addi	%r3,%r1,FRAME_TF
568	bl	_C_LABEL(ipkdb_trap_glue)
569	or.	%r3,%r3,%r3
570	beq	trapagain
571	b	trapexit
572
573ipkdbfault:
574	ba	_ipkdbfault
575_ipkdbfault:
576	mfsrr0	%r3
577	addi	%r3,%r3,4
578	mtsrr0	%r3
579	li	%r3,-1
580	rfi
581	ba	.	/* Protect against prefetch */
582
583/*
584 * int ipkdbfbyte(unsigned char *p)
585 */
586	.globl	_C_LABEL(ipkdbfbyte)
587_C_LABEL(ipkdbfbyte):
588	li	%r9,EXC_DSI		/* establish new fault routine */
589	lwz	%r5,0(%r9)
590	lis	%r6,ipkdbfault@ha
591	lwz	%r6,ipkdbfault@l(%r6)
592	stw	%r6,0(%r9)
593#ifdef	IPKDBUSERHACK
594#ifndef PPC_IBM4XX
595	lis	%r8,_C_LABEL(ipkdbsr)@ha
596	lwz	%r8,_C_LABEL(ipkdbsr)@l(%r8)
597	mtsr	USER_SR,%r8
598	isync
599#endif
600#endif
601	dcbst	%r0,%r9			/* flush data... */
602	sync
603	icbi	%r0,%r9			/* and instruction caches */
604	lbz	%r3,0(%r3)		/* fetch data */
605	stw	%r5,0(%r9)		/* restore previous fault handler */
606	dcbst	%r0,%r9			/* and flush data... */
607	sync
608	icbi	%r0,%r9			/* and instruction caches */
609	blr
610
611/*
612 * int ipkdbsbyte(unsigned char *p, int c)
613 */
614	.globl	_C_LABEL(ipkdbsbyte)
615_C_LABEL(ipkdbsbyte):
616	li	%r9,EXC_DSI		/* establish new fault routine */
617	lwz	%r5,0(%r9)
618	lis	%r6,ipkdbfault@ha
619	lwz	%r6,ipkdbfault@l(%r6)
620	stw	%r6,0(%r9)
621#ifdef	IPKDBUSERHACK
622#ifndef PPC_IBM4XX
623	lis	%r8,_C_LABEL(ipkdbsr)@ha
624	lwz	%r8,_C_LABEL(ipkdbsr)@l(%r8)
625	mtsr	USER_SR,%r8
626	isync
627#endif
628#endif
629	dcbst	%r0,%r9			/* flush data... */
630	sync
631	icbi	%r0,%r9			/* and instruction caches */
632	mr	%r6,%r3
633	xor	%r3,%r3,%r3
634	stb	%r4,0(%r6)
635	dcbst	%r0,%r6			/* Now do appropriate flushes
636					   to data... */
637	sync
638	icbi	%r0,%r6			/* and instruction caches */
639	stw	%r5,0(%r9)		/* restore previous fault handler */
640	dcbst	%r0,%r9			/* and flush data... */
641	sync
642	icbi	%r0,%r9			/* and instruction caches */
643	blr
644#endif	/* IPKDB */
645