xref: /freebsd/sys/powerpc/aim/trap_subr32.S (revision 9768746b)
1/* $FreeBSD$ */
2/* $NetBSD: trap_subr.S,v 1.20 2002/04/22 23:20:08 kleink Exp $	*/
3
4/*-
5 * Copyright (C) 1995, 1996 Wolfgang Solfrank.
6 * Copyright (C) 1995, 1996 TooLs GmbH.
7 * All rights reserved.
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 by TooLs GmbH.
20 * 4. The name of TooLs GmbH may not be used to endorse or promote products
21 *    derived from this software without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
24 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
25 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
26 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
27 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
28 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
29 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
30 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
31 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
32 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33 */
34
35/*
36 * NOTICE: This is not a standalone file.  to use it, #include it in
37 * your port's locore.S, like so:
38 *
39 *	#include <powerpc/aim/trap_subr.S>
40 */
41
42/*
43 * Save/restore segment registers
44 */
45#define RESTORE_SRS(pmap,sr)	mtsr    0,sr; \
46	lwz	sr,1*4(pmap);	mtsr	1,sr; \
47	lwz	sr,2*4(pmap);	mtsr	2,sr; \
48	lwz	sr,3*4(pmap);	mtsr	3,sr; \
49	lwz	sr,4*4(pmap);	mtsr	4,sr; \
50	lwz	sr,5*4(pmap);	mtsr	5,sr; \
51	lwz	sr,6*4(pmap);	mtsr	6,sr; \
52	lwz	sr,7*4(pmap);	mtsr	7,sr; \
53	lwz	sr,8*4(pmap);	mtsr	8,sr; \
54	lwz	sr,9*4(pmap);	mtsr	9,sr; \
55	lwz	sr,10*4(pmap);	mtsr	10,sr; \
56	lwz	sr,11*4(pmap);	mtsr	11,sr; \
57	/* Skip segment 12 (USER_SR), which is restored differently */ \
58	lwz	sr,13*4(pmap);	mtsr	13,sr; \
59	lwz	sr,14*4(pmap);	mtsr	14,sr; \
60	lwz	sr,15*4(pmap);	mtsr	15,sr; isync;
61
62/*
63 * User SRs are loaded through a pointer to the current pmap.
64 */
65#define RESTORE_USER_SRS(pmap,sr) \
66	GET_CPUINFO(pmap); \
67	lwz	pmap,PC_CURPMAP(pmap); \
68	lwzu	sr,PM_SR(pmap); \
69	RESTORE_SRS(pmap,sr) \
70	/* Restore SR 12 */ \
71	lwz	sr,12*4(pmap);	mtsr	12,sr; isync
72
73/*
74 * Kernel SRs are loaded directly from kernel_pmap_
75 */
76#define RESTORE_KERN_SRS(pmap,sr) \
77	lwz	pmap,TRAP_TOCBASE(0); \
78	lwz	pmap,CNAME(kernel_pmap_store)@got(pmap); \
79	lwzu	sr,PM_SR(pmap); \
80	RESTORE_SRS(pmap,sr)
81
82/*
83 * FRAME_SETUP assumes:
84 *	SPRG1		SP (1)
85 * 	SPRG3		trap type
86 *	savearea	r28-r31,DAR,DSISR   (DAR & DSISR only for DSI traps)
87 *	r28		LR
88 *	r29		CR
89 *	r30		scratch
90 *	r31		scratch
91 *	r1		kernel stack
92 *	SRR0/1		as at start of trap
93 */
94#define	FRAME_SETUP(savearea)						\
95/* Have to enable translation to allow access of kernel stack: */	\
96	GET_CPUINFO(%r31);						\
97	mfsrr0	%r30;							\
98	stw	%r30,(savearea+CPUSAVE_SRR0)(%r31);	/* save SRR0 */	\
99	mfsrr1	%r30;							\
100	stw	%r30,(savearea+CPUSAVE_SRR1)(%r31);	/* save SRR1 */	\
101	mfmsr	%r30;							\
102	ori	%r30,%r30,(PSL_DR|PSL_IR|PSL_RI)@l; /* relocation on */	\
103	mtmsr	%r30;			/* stack can now be accessed */	\
104	isync;								\
105	mfsprg1	%r31;			/* get saved SP */		\
106	stwu	%r31,-FRAMELEN(%r1);	/* save it in the callframe */	\
107	stw	%r0, FRAME_0+8(%r1);	/* save r0 in the trapframe */	\
108	stw	%r31,FRAME_1+8(%r1);	/* save SP   "      "       */	\
109	stw	%r2, FRAME_2+8(%r1);	/* save r2   "      "       */	\
110	stw	%r28,FRAME_LR+8(%r1);	/* save LR   "      "       */	\
111	stw	%r29,FRAME_CR+8(%r1);	/* save CR   "      "       */	\
112	GET_CPUINFO(%r2);						\
113	lwz	%r28,(savearea+CPUSAVE_R28)(%r2); /* get saved r28 */	\
114	lwz	%r29,(savearea+CPUSAVE_R29)(%r2); /* get saved r29 */	\
115	lwz	%r30,(savearea+CPUSAVE_R30)(%r2); /* get saved r30 */	\
116	lwz	%r31,(savearea+CPUSAVE_R31)(%r2); /* get saved r31 */	\
117	stw	%r3,  FRAME_3+8(%r1);	/* save r3-r31 */		\
118	stw	%r4,  FRAME_4+8(%r1);					\
119	stw	%r5,  FRAME_5+8(%r1);					\
120	stw	%r6,  FRAME_6+8(%r1);					\
121	stw	%r7,  FRAME_7+8(%r1);					\
122	stw	%r8,  FRAME_8+8(%r1);					\
123	stw	%r9,  FRAME_9+8(%r1);					\
124	stw	%r10, FRAME_10+8(%r1);					\
125	stw	%r11, FRAME_11+8(%r1);					\
126	stw	%r12, FRAME_12+8(%r1);					\
127	stw	%r13, FRAME_13+8(%r1);					\
128	stw	%r14, FRAME_14+8(%r1);					\
129	stw	%r15, FRAME_15+8(%r1);					\
130	stw	%r16, FRAME_16+8(%r1);					\
131	stw	%r17, FRAME_17+8(%r1);					\
132	stw	%r18, FRAME_18+8(%r1);					\
133	stw	%r19, FRAME_19+8(%r1);					\
134	stw	%r20, FRAME_20+8(%r1);					\
135	stw	%r21, FRAME_21+8(%r1);					\
136	stw	%r22, FRAME_22+8(%r1);					\
137	stw	%r23, FRAME_23+8(%r1);					\
138	stw	%r24, FRAME_24+8(%r1);					\
139	stw	%r25, FRAME_25+8(%r1);					\
140	stw	%r26, FRAME_26+8(%r1);					\
141	stw	%r27, FRAME_27+8(%r1);					\
142	stw	%r28, FRAME_28+8(%r1);					\
143	stw	%r29, FRAME_29+8(%r1);					\
144	stw	%r30, FRAME_30+8(%r1);					\
145	stw	%r31, FRAME_31+8(%r1);					\
146	lwz	%r28,(savearea+CPUSAVE_AIM_DAR)(%r2);  /* saved DAR */	\
147	lwz	%r29,(savearea+CPUSAVE_AIM_DSISR)(%r2);/* saved DSISR */\
148	lwz	%r30,(savearea+CPUSAVE_SRR0)(%r2); /* saved SRR0 */	\
149	lwz	%r31,(savearea+CPUSAVE_SRR1)(%r2); /* saved SRR1 */	\
150	mfxer	%r3;							\
151	mfctr	%r4;							\
152	mfsprg3	%r5;							\
153	stw	%r3, FRAME_XER+8(1);	/* save xer/ctr/exc */		\
154	stw	%r4, FRAME_CTR+8(1);					\
155	stw	%r5, FRAME_EXC+8(1);					\
156	stw	%r28,FRAME_AIM_DAR+8(1);				\
157	stw	%r29,FRAME_AIM_DSISR+8(1); /* save dsisr/srr0/srr1 */	\
158	stw	%r30,FRAME_SRR0+8(1);					\
159	stw	%r31,FRAME_SRR1+8(1);					\
160	lwz	%r2,PC_CURTHREAD(%r2)	/* set curthread pointer */
161
162#define	FRAME_LEAVE(savearea)						\
163/* Disable exceptions: */						\
164	mfmsr	%r2;							\
165	andi.	%r2,%r2,~PSL_EE@l;					\
166	mtmsr	%r2;							\
167	isync;								\
168/* Now restore regs: */							\
169	lwz	%r2,FRAME_SRR0+8(%r1);					\
170	lwz	%r3,FRAME_SRR1+8(%r1);					\
171	lwz	%r4,FRAME_CTR+8(%r1);					\
172	lwz	%r5,FRAME_XER+8(%r1);					\
173	lwz	%r6,FRAME_LR+8(%r1);					\
174	GET_CPUINFO(%r7);						\
175	stw	%r2,(savearea+CPUSAVE_SRR0)(%r7); /* save SRR0 */	\
176	stw	%r3,(savearea+CPUSAVE_SRR1)(%r7); /* save SRR1 */	\
177	lwz	%r7,FRAME_CR+8(%r1);					\
178	mtctr	%r4;							\
179	mtxer	%r5;							\
180	mtlr	%r6;							\
181	mtsprg1	%r7;			/* save cr */			\
182	lwz	%r31,FRAME_31+8(%r1);   /* restore r0-31 */		\
183	lwz	%r30,FRAME_30+8(%r1);					\
184	lwz	%r29,FRAME_29+8(%r1);					\
185	lwz	%r28,FRAME_28+8(%r1);					\
186	lwz	%r27,FRAME_27+8(%r1);					\
187	lwz	%r26,FRAME_26+8(%r1);					\
188	lwz	%r25,FRAME_25+8(%r1);					\
189	lwz	%r24,FRAME_24+8(%r1);					\
190	lwz	%r23,FRAME_23+8(%r1);					\
191	lwz	%r22,FRAME_22+8(%r1);					\
192	lwz	%r21,FRAME_21+8(%r1);					\
193	lwz	%r20,FRAME_20+8(%r1);					\
194	lwz	%r19,FRAME_19+8(%r1);					\
195	lwz	%r18,FRAME_18+8(%r1);					\
196	lwz	%r17,FRAME_17+8(%r1);					\
197	lwz	%r16,FRAME_16+8(%r1);					\
198	lwz	%r15,FRAME_15+8(%r1);					\
199	lwz	%r14,FRAME_14+8(%r1);					\
200	lwz	%r13,FRAME_13+8(%r1);					\
201	lwz	%r12,FRAME_12+8(%r1);					\
202	lwz	%r11,FRAME_11+8(%r1);					\
203	lwz	%r10,FRAME_10+8(%r1);					\
204	lwz	%r9, FRAME_9+8(%r1);					\
205	lwz	%r8, FRAME_8+8(%r1);					\
206	lwz	%r7, FRAME_7+8(%r1);					\
207	lwz	%r6, FRAME_6+8(%r1);					\
208	lwz	%r5, FRAME_5+8(%r1);					\
209	lwz	%r4, FRAME_4+8(%r1);					\
210	lwz	%r3, FRAME_3+8(%r1);					\
211	lwz	%r2, FRAME_2+8(%r1);					\
212	lwz	%r0, FRAME_0+8(%r1);					\
213	lwz	%r1, FRAME_1+8(%r1);					\
214/* Can't touch %r1 from here on */					\
215	mtsprg2	%r2;			/* save r2 & r3 */		\
216	mtsprg3	%r3;							\
217/* Disable translation, machine check and recoverability: */		\
218	mfmsr	%r2;							\
219	andi.	%r2,%r2,~(PSL_DR|PSL_IR|PSL_ME|PSL_RI)@l;	\
220	mtmsr	%r2;							\
221	isync;								\
222/* Decide whether we return to user mode: */				\
223	GET_CPUINFO(%r2);						\
224	lwz	%r3,(savearea+CPUSAVE_SRR1)(%r2);			\
225	mtcr	%r3;							\
226	bf	17,1f;			/* branch if PSL_PR is false */	\
227/* Restore user SRs */							\
228	RESTORE_USER_SRS(%r2,%r3);					\
2291:	mfsprg1	%r2;			/* restore cr */		\
230	mtcr	%r2;							\
231	GET_CPUINFO(%r2);						\
232	lwz	%r3,(savearea+CPUSAVE_SRR0)(%r2); /* restore srr0 */	\
233	mtsrr0	%r3;							\
234	lwz	%r3,(savearea+CPUSAVE_SRR1)(%r2); /* restore srr1 */	\
235									\
236	/* Make sure HV bit of MSR propagated to SRR1 */		\
237	mfmsr	%r2;							\
238	or	%r3,%r2,%r3;						\
239									\
240	mtsrr1	%r3;							\
241	mfsprg2	%r2;			/* restore r2 & r3 */		\
242	mfsprg3	%r3
243
244#ifdef KDTRACE_HOOKS
245	.data
246	.globl	dtrace_invop_calltrap_addr
247	.align	4
248	.type	dtrace_invop_calltrap_addr, @object
249        .size	dtrace_invop_calltrap_addr, 4
250dtrace_invop_calltrap_addr:
251	.word	0
252	.word	0
253
254	.text
255#endif
256
257/*
258 * The next two routines are 64-bit glue code. The first is used to test if
259 * we are on a 64-bit system. By copying it to the illegal instruction
260 * handler, we can test for 64-bit mode by trying to execute a 64-bit
261 * instruction and seeing what happens. The second gets copied in front
262 * of all the other handlers to restore 32-bit bridge mode when traps
263 * are taken.
264 */
265
266/* 64-bit test code. Sets SPRG2 to 0 if an illegal instruction is executed */
267
268	.globl	CNAME(testppc64),CNAME(testppc64size)
269CNAME(testppc64):
270	mtsprg1 %r31
271	mfsrr0  %r31
272	addi	%r31, %r31, 4
273	mtsrr0  %r31
274
275	li	%r31, 0
276	mtsprg2 %r31
277	mfsprg1 %r31
278
279	rfi
280CNAME(testppc64size) = .-CNAME(testppc64)
281
282
283/* 64-bit bridge mode restore snippet. Gets copied in front of everything else
284 * on 64-bit systems. */
285
286	.globl	CNAME(restorebridge),CNAME(restorebridgesize)
287CNAME(restorebridge):
288	mtsprg1	%r31
289	mfmsr	%r31
290	clrldi	%r31,%r31,1
291	mtmsrd	%r31
292	mfsprg1	%r31
293	isync
294CNAME(restorebridgesize) = .-CNAME(restorebridge)
295
296/*
297 * Processor reset exception handler. These are typically
298 * the first instructions the processor executes after a
299 * software reset. We do this in two bits so that we are
300 * not still hanging around in the trap handling region
301 * once the MMU is turned on.
302 */
303	.globl	CNAME(rstcode), CNAME(rstcodeend)
304CNAME(rstcode):
305	lwz	%r31, TRAP_GENTRAP(0)
306	addi	%r31, %r31, (cpu_reset - generictrap)
307	mtlr	%r31
308	blrl
309CNAME(rstcodeend):
310
311cpu_reset:
312	bl	1f
313
314	.space	124
315
3161:
317	mflr	%r1
318	addi	%r1,%r1,(124-16)@l
319	lwz	%r30,TRAP_TOCBASE(0)
320
321	bl	CNAME(cpudep_ap_early_bootstrap)
322	lis	%r3,1@l
323	bl	CNAME(pmap_cpu_bootstrap)
324	bl	CNAME(cpudep_ap_bootstrap)
325	mr	%r1,%r3
326	bl	CNAME(cpudep_ap_setup)
327	GET_CPUINFO(%r5)
328	lwz	%r3,(PC_RESTORE)(%r5)
329	cmplwi	%cr0,%r3,0
330	beq	%cr0,2f
331	li	%r4, 1
332	b	CNAME(longjmp)
3332:
334#ifdef SMP
335	bl	CNAME(machdep_ap_bootstrap)
336#endif
337
338	/* Should not be reached */
3399:
340	b	9b
341
342/*
343 * This code gets copied to all the trap vectors
344 * (except ISI/DSI, ALI, and the interrupts)
345 */
346
347	.globl	CNAME(trapcode),CNAME(trapcodeend)
348CNAME(trapcode):
349	mtsprg1	%r1			/* save SP */
350	mflr	%r1			/* Save the old LR in r1 */
351	mtsprg2 %r1			/* And then in SPRG2 */
352	lwz	%r1, TRAP_ENTRY(0)	/* Get branch address */
353	mtlr	%r1
354	li	%r1, 0xe0		/* How to get the vector from LR */
355	blrl				/* LR & (0xff00 | r1) is exception # */
356CNAME(trapcodeend):
357
358/*
359 * For ALI: has to save DSISR and DAR
360 */
361	.globl	CNAME(alitrap),CNAME(aliend)
362CNAME(alitrap):
363	mtsprg1	%r1			/* save SP */
364	GET_CPUINFO(%r1)
365	stw	%r28,(PC_TEMPSAVE+CPUSAVE_R28)(%r1)	/* free r28-r31 */
366	stw	%r29,(PC_TEMPSAVE+CPUSAVE_R29)(%r1)
367	stw	%r30,(PC_TEMPSAVE+CPUSAVE_R30)(%r1)
368	stw	%r31,(PC_TEMPSAVE+CPUSAVE_R31)(%r1)
369	mfdar	%r30
370	mfdsisr	%r31
371	stw	%r30,(PC_TEMPSAVE+CPUSAVE_AIM_DAR)(%r1)
372	stw	%r31,(PC_TEMPSAVE+CPUSAVE_AIM_DSISR)(%r1)
373	mfsprg1	%r1			/* restore SP, in case of branch */
374	mflr	%r28			/* save LR */
375	mfcr	%r29			/* save CR */
376
377	/* Put our exception vector in SPRG3 */
378	li	%r31, EXC_ALI
379	mtsprg3	%r31
380
381	/* Test whether we already had PR set */
382	mfsrr1	%r31
383	mtcr	%r31
384
385	/* Jump to s_trap */
386	lwz	%r31, TRAP_GENTRAP(0)
387	addi	%r31, %r31, (s_trap - generictrap)
388	mtlr	%r31
389	blrl
390CNAME(aliend):
391
392/*
393 * G2 specific: instuction TLB miss.
394 */
395	.globl	CNAME(imisstrap),CNAME(imisssize)
396CNAME(imisstrap):
397	mfspr %r2, SPR_HASH1		/* get first pointer */
398	addi %r1, 0, 8			/* load 8 for counter */
399	mfctr %r0			/* save counter */
400	mfspr %r3, SPR_ICMP		/* get first compare value */
401	addi %r2, %r2, -8		/* pre dec the pointer */
402im0:
403	mtctr %r1			/* load counter */
404im1:
405	lwzu %r1, 8(%r2)		/* get next pte */
406	cmp 0, 0, %r1, %r3		/* see if found pte */
407	bdnzf 2, im1			/* dec count br if cmp ne and if
408					 * count not zero */
409	bne instr_sec_hash		/* if not found set up second hash
410					 * or exit */
411	lwz %r1, +4(%r2)		/* load tlb entry lower-word */
412	andi. %r3, %r1, 8		/* check G bit */
413	bne do_isi_prot			/* if guarded, take an ISI */
414	mtctr %r0			/* restore counter */
415	mfspr %r0, SPR_IMISS		/* get the miss address for the tlbli */
416	mfspr %r3, SPR_SRR1		/* get the saved cr0 bits */
417	mtcrf 0x80, %r3			/* restore CR0 */
418	mtspr SPR_RPA, %r1		/* set the pte */
419	ori %r1, %r1, 0x100		/* set reference bit */
420	srwi %r1, %r1, 8		/* get byte 7 of pte */
421	tlbli %r0 			/* load the itlb */
422	stb %r1, +6(%r2)		/* update page table */
423	rfi				/* return to executing program */
424
425instr_sec_hash:
426	andi. %r1, %r3, 0x0040		/* see if we have done second hash */
427	bne do_isi			/* if so, go to ISI interrupt */
428	mfspr %r2, SPR_HASH2		/* get the second pointer */
429	ori %r3, %r3, 0x0040		/* change the compare value */
430	addi %r1, 0, 8			/* load 8 for counter */
431	addi %r2, %r2, -8		/* pre dec for update on load */
432	b im0				/* try second hash */
433
434/* Create a faked ISI interrupt as the address was not found */
435do_isi_prot:
436	mfspr %r3, SPR_SRR1		/* get srr1 */
437	andi. %r2, %r3, 0xffff		/* clean upper srr1 */
438	addis %r2, %r2, 0x0800		/* or in srr<4> = 1 to flag prot
439					 * violation */
440	b isi1
441do_isi:
442	mfspr %r3, SPR_SRR1		/* get srr1 */
443	andi. %r2, %r3, 0xffff		/* clean srr1 */
444	addis %r2, %r2, 0x4000		/* or in srr1<1> = 1 to flag pte
445					 * not found */
446isi1:
447	mtctr %r0			/* restore counter */
448	mtspr SPR_SRR1, %r2		/* set srr1 */
449	mfmsr %r0			/* get msr */
450	xoris %r0, %r0, 0x2		/* flip the msr<tgpr> bit */
451	mtcrf 0x80, %r3			/* restore CR0 */
452	mtmsr %r0			/* flip back to the native gprs */
453	ba EXC_ISI 			/* go to instr. access interrupt */
454
455CNAME(imisssize) = .-CNAME(imisstrap)
456
457/*
458 * G2 specific: data load TLB miss.
459 */
460	.globl	CNAME(dlmisstrap),CNAME(dlmisssize)
461CNAME(dlmisstrap):
462	mfspr %r2, SPR_HASH1		/* get first pointer */
463	addi %r1, 0, 8			/* load 8 for counter */
464	mfctr %r0			/* save counter */
465	mfspr %r3, SPR_DCMP		/* get first compare value */
466	addi %r2, %r2, -8		/* pre dec the pointer */
467dm0:
468	mtctr %r1			/* load counter */
469dm1:
470	lwzu %r1, 8(%r2)		/* get next pte */
471	cmp 0, 0, %r1, %r3		/* see if found pte */
472	bdnzf 2, dm1			/* dec count br if cmp ne and if
473					 * count not zero */
474	bne data_sec_hash		/* if not found set up second hash
475					 * or exit */
476	lwz %r1, +4(%r2)		/* load tlb entry lower-word */
477	mtctr %r0			/* restore counter */
478	mfspr %r0, SPR_DMISS		/* get the miss address for the tlbld */
479	mfspr %r3, SPR_SRR1		/* get the saved cr0 bits */
480	mtcrf 0x80, %r3			/* restore CR0 */
481	mtspr SPR_RPA, %r1		/* set the pte */
482	ori %r1, %r1, 0x100		/* set reference bit */
483	srwi %r1, %r1, 8		/* get byte 7 of pte */
484	tlbld %r0			/* load the dtlb */
485	stb %r1, +6(%r2)		/* update page table */
486	rfi				/* return to executing program */
487
488data_sec_hash:
489	andi. %r1, %r3, 0x0040		/* see if we have done second hash */
490	bne do_dsi			/* if so, go to DSI interrupt */
491	mfspr %r2, SPR_HASH2		/* get the second pointer */
492	ori %r3, %r3, 0x0040		/* change the compare value */
493	addi %r1, 0, 8			/* load 8 for counter */
494	addi %r2, %r2, -8		/* pre dec for update on load */
495	b dm0				/* try second hash */
496
497CNAME(dlmisssize) = .-CNAME(dlmisstrap)
498
499/*
500 *  G2 specific: data store TLB miss.
501 */
502	.globl	CNAME(dsmisstrap),CNAME(dsmisssize)
503CNAME(dsmisstrap):
504	mfspr %r2, SPR_HASH1		/* get first pointer */
505	addi %r1, 0, 8			/* load 8 for counter */
506	mfctr %r0			/* save counter */
507	mfspr %r3, SPR_DCMP		/* get first compare value */
508	addi %r2, %r2, -8		/* pre dec the pointer */
509ds0:
510	mtctr %r1			/* load counter */
511ds1:
512	lwzu %r1, 8(%r2)		/* get next pte */
513	cmp 0, 0, %r1, %r3		/* see if found pte */
514	bdnzf 2, ds1			/* dec count br if cmp ne and if
515					 * count not zero */
516	bne data_store_sec_hash		/* if not found set up second hash
517					 * or exit */
518	lwz %r1, +4(%r2)		/* load tlb entry lower-word */
519	andi. %r3, %r1, 0x80		/* check the C-bit */
520	beq data_store_chk_prot		/* if (C==0)
521					 *     go check protection modes */
522ds2:
523	mtctr %r0			/* restore counter */
524	mfspr %r0, SPR_DMISS		/* get the miss address for the tlbld */
525	mfspr %r3, SPR_SRR1		/* get the saved cr0 bits */
526	mtcrf 0x80, %r3			/* restore CR0 */
527	mtspr SPR_RPA, %r1		/* set the pte */
528	tlbld %r0			/* load the dtlb */
529	rfi				/* return to executing program */
530
531data_store_sec_hash:
532	andi. %r1, %r3, 0x0040		/* see if we have done second hash */
533	bne do_dsi			/* if so, go to DSI interrupt */
534	mfspr %r2, SPR_HASH2		/* get the second pointer */
535	ori %r3, %r3, 0x0040		/* change the compare value */
536	addi %r1, 0, 8			/* load 8 for counter */
537	addi %r2, %r2, -8		/* pre dec for update on load */
538	b ds0				/* try second hash */
539
540/* Check the protection before setting PTE(c-bit) */
541data_store_chk_prot:
542	rlwinm. %r3,%r1,30,0,1		/* test PP */
543	bge- chk0			/* if (PP == 00 or PP == 01)
544					 *     goto chk0: */
545	andi. %r3, %r1, 1		/* test PP[0] */
546	beq+ chk2			/* return if PP[0] == 0 */
547	b do_dsi_prot			/* else DSIp */
548chk0:
549	mfspr %r3,SPR_SRR1		/* get old msr */
550	andis. %r3,%r3,0x0008		/* test the KEY bit (SRR1-bit 12) */
551	beq chk2			/* if (KEY==0) goto chk2: */
552	b do_dsi_prot			/* else do_dsi_prot */
553chk2:
554	ori %r1, %r1, 0x180		/* set reference and change bit */
555	sth %r1, 6(%r2)			/* update page table */
556	b ds2				/* and back we go */
557
558/* Create a faked DSI interrupt as the address was not found */
559do_dsi:
560	mfspr %r3, SPR_SRR1		/* get srr1 */
561	rlwinm %r1,%r3,9,6,6		/* get srr1<flag> to bit 6 for
562					 * load/store, zero rest */
563	addis %r1, %r1, 0x4000		/* or in dsisr<1> = 1 to flag pte
564					 * not found */
565	b dsi1
566
567do_dsi_prot:
568	mfspr %r3, SPR_SRR1		/* get srr1 */
569	rlwinm %r1,%r3,9,6,6		/* get srr1<flag> to bit 6 for
570					   *load/store, zero rest */
571	addis %r1, %r1, 0x0800		/* or in dsisr<4> = 1 to flag prot
572					 * violation */
573
574dsi1:
575	mtctr %r0			/* restore counter */
576	andi. %r2, %r3, 0xffff		/* clear upper bits of srr1 */
577	mtspr SPR_SRR1, %r2		/* set srr1 */
578	mtspr SPR_DSISR, %r1		/* load the dsisr */
579	mfspr %r1, SPR_DMISS		/* get miss address */
580	rlwinm. %r2,%r2,0,31,31		/* test LE bit */
581	beq dsi2			/* if little endian then: */
582	xor %r1, %r1, 0x07		/* de-mung the data address */
583dsi2:
584	mtspr SPR_DAR, %r1		/* put in dar */
585	mfmsr %r0			/* get msr */
586	xoris %r0, %r0, 0x2		/* flip the msr<tgpr> bit */
587	mtcrf 0x80, %r3			/* restore CR0 */
588	mtmsr %r0			/* flip back to the native gprs */
589	ba EXC_DSI			/* branch to DSI interrupt */
590
591CNAME(dsmisssize) = .-CNAME(dsmisstrap)
592
593/*
594 * Similar to the above for DSI
595 * Has to handle BAT spills
596 * and standard pagetable spills
597 */
598	.globl	CNAME(dsitrap),CNAME(dsiend)
599CNAME(dsitrap):
600	mtsprg1	%r1			/* save SP */
601	GET_CPUINFO(%r1)
602	stw	%r28,(PC_DISISAVE+CPUSAVE_R28)(%r1)	/* free r28-r31 */
603	stw	%r29,(PC_DISISAVE+CPUSAVE_R29)(%r1)
604	stw	%r30,(PC_DISISAVE+CPUSAVE_R30)(%r1)
605	stw	%r31,(PC_DISISAVE+CPUSAVE_R31)(%r1)
606	mfsprg1	%r1			/* restore SP */
607	mfcr	%r29			/* save CR */
608	mfxer	%r30			/* save XER */
609	mtsprg2	%r30			/* in SPRG2 */
610	mfsrr1	%r31			/* test kernel mode */
611	mtcr	%r31
612	bt	17,1f			/* branch if PSL_PR is set */
613	mfdar	%r31			/* get fault address */
614	rlwinm	%r31,%r31,7,25,28	/* get segment * 8 */
615
616	/* get batu */
617	lwz	%r30,TRAP_TOCBASE(0)
618	lwz	%r30,CNAME(battable)@got(%r30)
619	add	%r31,%r30,%r31
620	lwz	%r30,0(%r31)
621	mtcr	%r30
622	bf	30,1f			/* branch if supervisor valid is
623					   false */
624	/* get batl */
625	lwz	%r31,4(%r31)
626/* We randomly use the highest two bat registers here */
627	mftb	%r28
628	andi.	%r28,%r28,1
629	bne	2f
630	mtdbatu	2,%r30
631	mtdbatl	2,%r31
632	b	3f
6332:
634	mtdbatu	3,%r30
635	mtdbatl	3,%r31
6363:
637	mfsprg2	%r30			/* restore XER */
638	mtxer	%r30
639	mtcr	%r29			/* restore CR */
640	mtsprg1	%r1
641	GET_CPUINFO(%r1)
642	lwz	%r28,(PC_DISISAVE+CPUSAVE_R28)(%r1)	/* restore r28-r31 */
643	lwz	%r29,(PC_DISISAVE+CPUSAVE_R29)(%r1)
644	lwz	%r30,(PC_DISISAVE+CPUSAVE_R30)(%r1)
645	lwz	%r31,(PC_DISISAVE+CPUSAVE_R31)(%r1)
646	mfsprg1	%r1
647	rfi				/* return to trapped code */
6481:
649	mflr	%r28			/* save LR (SP already saved) */
650
651	/* Jump to disitrap */
652	lwz	%r1, TRAP_GENTRAP(0)
653	addi	%r1, %r1, (disitrap - generictrap)
654	mtlr	%r1
655	blrl
656CNAME(dsiend):
657
658/*
659 * Preamble code for DSI/ISI traps
660 */
661disitrap:
662	/* Write the trap vector to SPRG3 by computing LR & 0xff00 */
663	mflr	%r1
664	andi.	%r1,%r1,0xff00
665	mtsprg3	%r1
666
667	GET_CPUINFO(%r1)
668	lwz	%r30,(PC_DISISAVE+CPUSAVE_R28)(%r1)
669	stw	%r30,(PC_TEMPSAVE+CPUSAVE_R28)(%r1)
670	lwz	%r31,(PC_DISISAVE+CPUSAVE_R29)(%r1)
671	stw	%r31,(PC_TEMPSAVE+CPUSAVE_R29)(%r1)
672	lwz	%r30,(PC_DISISAVE+CPUSAVE_R30)(%r1)
673	stw	%r30,(PC_TEMPSAVE+CPUSAVE_R30)(%r1)
674	lwz	%r31,(PC_DISISAVE+CPUSAVE_R31)(%r1)
675	stw	%r31,(PC_TEMPSAVE+CPUSAVE_R31)(%r1)
676	mfdar	%r30
677	mfdsisr	%r31
678	stw	%r30,(PC_TEMPSAVE+CPUSAVE_AIM_DAR)(%r1)
679	stw	%r31,(PC_TEMPSAVE+CPUSAVE_AIM_DSISR)(%r1)
680
681#ifdef KDB
682	/* Try to detect a kernel stack overflow */
683	mfsrr1	%r31
684	mtcr	%r31
685	bt	17,realtrap		/* branch is user mode */
686	mfsprg1	%r31			/* get old SP */
687	clrrwi	%r31,%r31,12		/* Round SP down to nearest page */
688	sub.	%r30,%r31,%r30		/* SP - DAR */
689	bge	1f
690	neg	%r30,%r30		/* modulo value */
6911:	cmplwi	%cr0,%r30,4096		/* is DAR within a page of SP? */
692	bge	%cr0,realtrap		/* no, too far away. */
693
694	/* Now convert this DSI into a DDB trap.  */
695	GET_CPUINFO(%r1)
696	lwz	%r30,(PC_TEMPSAVE+CPUSAVE_AIM_DAR)(%r1) /* get DAR */
697	stw	%r30,(PC_DBSAVE  +CPUSAVE_AIM_DAR)(%r1) /* save DAR */
698	lwz	%r31,(PC_TEMPSAVE+CPUSAVE_AIM_DSISR)(%r1) /* get DSISR */
699	stw	%r31,(PC_DBSAVE  +CPUSAVE_AIM_DSISR)(%r1) /* save DSISR */
700	lwz	%r30,(PC_DISISAVE+CPUSAVE_R28)(%r1) /* get  r28 */
701	stw	%r30,(PC_DBSAVE  +CPUSAVE_R28)(%r1) /* save r28 */
702	lwz	%r31,(PC_DISISAVE+CPUSAVE_R29)(%r1) /* get  r29 */
703	stw	%r31,(PC_DBSAVE  +CPUSAVE_R29)(%r1) /* save r29 */
704	lwz	%r30,(PC_DISISAVE+CPUSAVE_R30)(%r1) /* get  r30 */
705	stw	%r30,(PC_DBSAVE  +CPUSAVE_R30)(%r1) /* save r30 */
706	lwz	%r31,(PC_DISISAVE+CPUSAVE_R31)(%r1) /* get  r31 */
707	stw	%r31,(PC_DBSAVE  +CPUSAVE_R31)(%r1) /* save r31 */
708	b	dbtrap
709#endif
710
711	/* XXX need stack probe here */
712realtrap:
713/* Test whether we already had PR set */
714	mfsrr1	%r1
715	mtcr	%r1
716	mfsprg1	%r1			/* restore SP (might have been
717					   overwritten) */
718	bf	17,k_trap		/* branch if PSL_PR is false */
719	GET_CPUINFO(%r1)
720	lwz	%r1,PC_CURPCB(%r1)
721	RESTORE_KERN_SRS(%r30,%r31)	/* enable kernel mapping */
722	b	s_trap
723
724/*
725 * generictrap does some standard setup for trap handling to minimize
726 * the code that need be installed in the actual vectors. It expects
727 * the following conditions.
728 *
729 * R1 - Trap vector = LR & (0xff00 | R1)
730 * SPRG1 - Original R1 contents
731 * SPRG2 - Original LR
732 */
733
734	.globl	CNAME(generictrap64)
735generictrap64:
736	mtsprg3	%r31
737	mfmsr	%r31
738	clrldi	%r31,%r31,1
739	mtmsrd	%r31
740	mfsprg3	%r31
741	isync
742
743	.globl	CNAME(generictrap)
744generictrap:
745	/* Save R1 for computing the exception vector */
746	mtsprg3 %r1
747
748	/* Save interesting registers */
749	GET_CPUINFO(%r1)
750	stw	%r28,(PC_TEMPSAVE+CPUSAVE_R28)(%r1)	/* free r28-r31 */
751	stw	%r29,(PC_TEMPSAVE+CPUSAVE_R29)(%r1)
752	stw	%r30,(PC_TEMPSAVE+CPUSAVE_R30)(%r1)
753	stw	%r31,(PC_TEMPSAVE+CPUSAVE_R31)(%r1)
754	mfsprg1	%r1			/* restore SP, in case of branch */
755	mfsprg2	%r28			/* save LR */
756	mfcr	%r29			/* save CR */
757
758	/* Compute the exception vector from the link register */
759	mfsprg3 %r31
760	ori	%r31,%r31,0xff00
761	mflr	%r30
762	and	%r30,%r30,%r31
763	mtsprg3	%r30
764
765	/* Test whether we already had PR set */
766	mfsrr1	%r31
767	mtcr	%r31
768
769s_trap:
770	bf	17,k_trap		/* branch if PSL_PR is false */
771	GET_CPUINFO(%r1)
772u_trap:
773	lwz	%r1,PC_CURPCB(%r1)
774	RESTORE_KERN_SRS(%r30,%r31)	/* enable kernel mapping */
775
776/*
777 * Now the common trap catching code.
778 */
779k_trap:
780	FRAME_SETUP(PC_TEMPSAVE)
781	/* Restore USER_SR */
782	GET_CPUINFO(%r30)
783	lwz	%r30,PC_CURPCB(%r30)
784	lwz	%r30,PCB_AIM_USR_VSID(%r30)
785	mtsr	USER_SR,%r30; sync; isync
786/* Call C interrupt dispatcher: */
787trapagain:
788	addi	%r3,%r1,8
789	bl	CNAME(powerpc_interrupt)
790	.globl	CNAME(trapexit)		/* backtrace code sentinel */
791CNAME(trapexit):
792
793/* Disable interrupts: */
794	mfmsr	%r3
795	andi.	%r3,%r3,~PSL_EE@l
796	mtmsr	%r3
797	isync
798/* Test AST pending: */
799	lwz	%r5,FRAME_SRR1+8(%r1)
800	mtcr	%r5
801	bf	17,1f			/* branch if PSL_PR is false */
802
803	GET_CPUINFO(%r3)		/* get per-CPU pointer */
804	lwz	%r4, TD_AST(%r2)	/* get thread ast value
805					 * (r2 is curthread) */
806	cmpwi	%r4, 0
807	beq	1f
808	mfmsr	%r3			/* re-enable interrupts */
809	ori	%r3,%r3,PSL_EE@l
810	mtmsr	%r3
811	isync
812	addi	%r3,%r1,8
813	bl	CNAME(ast)
814	.globl	CNAME(asttrapexit)	/* backtrace code sentinel #2 */
815CNAME(asttrapexit):
816	b	trapexit		/* test ast ret value ? */
8171:
818	FRAME_LEAVE(PC_TEMPSAVE)
819
820	.globl	CNAME(rfi_patch1)	/* replace rfi with rfid on ppc64 */
821CNAME(rfi_patch1):
822	rfi
823
824	.globl	CNAME(rfid_patch)
825CNAME(rfid_patch):
826	rfid
827
828#if defined(KDB)
829/*
830 * Deliberate entry to dbtrap
831 */
832	.globl	CNAME(breakpoint)
833CNAME(breakpoint):
834	mtsprg1	%r1
835	mfmsr	%r3
836	mtsrr1	%r3
837	andi.	%r3,%r3,~(PSL_EE|PSL_ME)@l
838	mtmsr	%r3			/* disable interrupts */
839	isync
840	GET_CPUINFO(%r3)
841	stw	%r28,(PC_DBSAVE+CPUSAVE_R28)(%r3)
842	stw	%r29,(PC_DBSAVE+CPUSAVE_R29)(%r3)
843	stw	%r30,(PC_DBSAVE+CPUSAVE_R30)(%r3)
844	stw	%r31,(PC_DBSAVE+CPUSAVE_R31)(%r3)
845	mflr	%r28
846	li	%r29,EXC_BPT
847	mtlr	%r29
848	mfcr	%r29
849	mtsrr0	%r28
850
851/*
852 * Now the kdb trap catching code.
853 */
854dbtrap:
855	/* Write the trap vector to SPRG3 by computing LR & 0xff00 */
856	mflr	%r1
857	andi.	%r1,%r1,0xff00
858	mtsprg3	%r1
859
860	lwz	%r1,TRAP_TOCBASE(0)		/* get new SP */
861	lwz	%r1,trapstk@got(%r1)
862	addi	%r1,%r1,TRAPSTKSZ-16
863
864	FRAME_SETUP(PC_DBSAVE)
865/* Call C trap code: */
866	addi	%r3,%r1,8
867	bl	CNAME(db_trap_glue)
868	or.	%r3,%r3,%r3
869	bne	dbleave
870/* This wasn't for KDB, so switch to real trap: */
871	lwz	%r3,FRAME_EXC+8(%r1)	/* save exception */
872	GET_CPUINFO(%r4)
873	stw	%r3,(PC_DBSAVE+CPUSAVE_R31)(%r4)
874	FRAME_LEAVE(PC_DBSAVE)
875	mtsprg1	%r1			/* prepare for entrance to realtrap */
876	GET_CPUINFO(%r1)
877	stw	%r28,(PC_TEMPSAVE+CPUSAVE_R28)(%r1)
878	stw	%r29,(PC_TEMPSAVE+CPUSAVE_R29)(%r1)
879	stw	%r30,(PC_TEMPSAVE+CPUSAVE_R30)(%r1)
880	stw	%r31,(PC_TEMPSAVE+CPUSAVE_R31)(%r1)
881	mflr	%r28
882	mfcr	%r29
883	lwz	%r31,(PC_DBSAVE+CPUSAVE_R31)(%r1)
884	mtsprg3	%r31			/* SPRG3 was clobbered by FRAME_LEAVE */
885	mfsprg1	%r1
886	b	realtrap
887dbleave:
888	FRAME_LEAVE(PC_DBSAVE)
889	.globl	CNAME(rfi_patch2)	/* replace rfi with rfid on ppc64 */
890CNAME(rfi_patch2):
891	rfi
892
893/*
894 * In case of KDB we want a separate trap catcher for it
895 */
896	.globl	CNAME(dblow),CNAME(dbend)
897CNAME(dblow):
898	mtsprg1	%r1			/* save SP */
899	mtsprg2	%r29			/* save r29 */
900	mfcr	%r29			/* save CR in r29 */
901	mfsrr1	%r1
902	mtcr	%r1
903	bf	17,1f			/* branch if privileged */
904	/* Unprivileged case */
905	mtcr	%r29			/* put the condition register back */
906        mfsprg2	%r29			/* ... and r29 */
907        mflr	%r1			/* save LR */
908	mtsprg2 %r1			/* And then in SPRG2 */
909
910	lwz	%r1, TRAP_ENTRY(0)	/* Get branch address */
911	mtlr	%r1
912	li	%r1, 0			/* How to get the vector from LR */
913	blrl				/* LR & (0xff00 | r1) is exception # */
9141:
915	/* Privileged, so drop to KDB */
916	GET_CPUINFO(%r1)
917	stw	%r28,(PC_DBSAVE+CPUSAVE_R28)(%r1)	/* free r28 */
918        mfsprg2	%r28				/* r29 holds cr...  */
919        stw	%r28,(PC_DBSAVE+CPUSAVE_R29)(%r1)	/* free r29 */
920        stw	%r30,(PC_DBSAVE+CPUSAVE_R30)(%r1)	/* free r30 */
921        stw	%r31,(PC_DBSAVE+CPUSAVE_R31)(%r1)	/* free r31 */
922        mflr	%r28					/* save LR */
923
924	/* Jump to dbtrap */
925	lwz	%r1, TRAP_GENTRAP(0)
926	addi	%r1, %r1, (dbtrap - generictrap)
927	mtlr	%r1
928	blrl
929CNAME(dbend):
930#endif /* KDB */
931