xref: /freebsd/sys/powerpc/aim/trap_subr32.S (revision 62cfcf62f627e5093fb37026a6d8c98e4d2ef04c)
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
320	bl	CNAME(cpudep_ap_early_bootstrap)
321	lis	%r3,1@l
322	bl	CNAME(pmap_cpu_bootstrap)
323	bl	CNAME(cpudep_ap_bootstrap)
324	mr	%r1,%r3
325	bl	CNAME(cpudep_ap_setup)
326	GET_CPUINFO(%r5)
327	lwz	%r3,(PC_RESTORE)(%r5)
328	cmplwi	%cr0,%r3,0
329	beq	%cr0,2f
330	li	%r4, 1
331	b	CNAME(longjmp)
3322:
333#ifdef SMP
334	bl	CNAME(machdep_ap_bootstrap)
335#endif
336
337	/* Should not be reached */
3389:
339	b	9b
340
341/*
342 * This code gets copied to all the trap vectors
343 * (except ISI/DSI, ALI, and the interrupts)
344 */
345
346	.globl	CNAME(trapcode),CNAME(trapcodeend)
347CNAME(trapcode):
348	mtsprg1	%r1			/* save SP */
349	mflr	%r1			/* Save the old LR in r1 */
350	mtsprg2 %r1			/* And then in SPRG2 */
351	lwz	%r1, TRAP_ENTRY(0)	/* Get branch address */
352	mtlr	%r1
353	li	%r1, 0xe0		/* How to get the vector from LR */
354	blrl				/* LR & (0xff00 | r1) is exception # */
355CNAME(trapcodeend):
356
357/*
358 * For ALI: has to save DSISR and DAR
359 */
360	.globl	CNAME(alitrap),CNAME(aliend)
361CNAME(alitrap):
362	mtsprg1	%r1			/* save SP */
363	GET_CPUINFO(%r1)
364	stw	%r28,(PC_TEMPSAVE+CPUSAVE_R28)(%r1)	/* free r28-r31 */
365	stw	%r29,(PC_TEMPSAVE+CPUSAVE_R29)(%r1)
366	stw	%r30,(PC_TEMPSAVE+CPUSAVE_R30)(%r1)
367	stw	%r31,(PC_TEMPSAVE+CPUSAVE_R31)(%r1)
368	mfdar	%r30
369	mfdsisr	%r31
370	stw	%r30,(PC_TEMPSAVE+CPUSAVE_AIM_DAR)(%r1)
371	stw	%r31,(PC_TEMPSAVE+CPUSAVE_AIM_DSISR)(%r1)
372	mfsprg1	%r1			/* restore SP, in case of branch */
373	mflr	%r28			/* save LR */
374	mfcr	%r29			/* save CR */
375
376	/* Put our exception vector in SPRG3 */
377	li	%r31, EXC_ALI
378	mtsprg3	%r31
379
380	/* Test whether we already had PR set */
381	mfsrr1	%r31
382	mtcr	%r31
383
384	/* Jump to s_trap */
385	lwz	%r31, TRAP_GENTRAP(0)
386	addi	%r31, %r31, (s_trap - generictrap)
387	mtlr	%r31
388	blrl
389CNAME(aliend):
390
391/*
392 * G2 specific: instuction TLB miss.
393 */
394	.globl	CNAME(imisstrap),CNAME(imisssize)
395CNAME(imisstrap):
396	mfspr %r2, SPR_HASH1		/* get first pointer */
397	addi %r1, 0, 8			/* load 8 for counter */
398	mfctr %r0			/* save counter */
399	mfspr %r3, SPR_ICMP		/* get first compare value */
400	addi %r2, %r2, -8		/* pre dec the pointer */
401im0:
402	mtctr %r1			/* load counter */
403im1:
404	lwzu %r1, 8(%r2)		/* get next pte */
405	cmp 0, 0, %r1, %r3		/* see if found pte */
406	bdnzf 2, im1			/* dec count br if cmp ne and if
407					 * count not zero */
408	bne instr_sec_hash		/* if not found set up second hash
409					 * or exit */
410	lwz %r1, +4(%r2)		/* load tlb entry lower-word */
411	andi. %r3, %r1, 8		/* check G bit */
412	bne do_isi_prot			/* if guarded, take an ISI */
413	mtctr %r0			/* restore counter */
414	mfspr %r0, SPR_IMISS		/* get the miss address for the tlbli */
415	mfspr %r3, SPR_SRR1		/* get the saved cr0 bits */
416	mtcrf 0x80, %r3			/* restore CR0 */
417	mtspr SPR_RPA, %r1		/* set the pte */
418	ori %r1, %r1, 0x100		/* set reference bit */
419	srwi %r1, %r1, 8		/* get byte 7 of pte */
420	tlbli %r0 			/* load the itlb */
421	stb %r1, +6(%r2)		/* update page table */
422	rfi				/* return to executing program */
423
424instr_sec_hash:
425	andi. %r1, %r3, 0x0040		/* see if we have done second hash */
426	bne do_isi			/* if so, go to ISI interrupt */
427	mfspr %r2, SPR_HASH2		/* get the second pointer */
428	ori %r3, %r3, 0x0040		/* change the compare value */
429	addi %r1, 0, 8			/* load 8 for counter */
430	addi %r2, %r2, -8		/* pre dec for update on load */
431	b im0				/* try second hash */
432
433/* Create a faked ISI interrupt as the address was not found */
434do_isi_prot:
435	mfspr %r3, SPR_SRR1		/* get srr1 */
436	andi. %r2, %r3, 0xffff		/* clean upper srr1 */
437	addis %r2, %r2, 0x0800		/* or in srr<4> = 1 to flag prot
438					 * violation */
439	b isi1
440do_isi:
441	mfspr %r3, SPR_SRR1		/* get srr1 */
442	andi. %r2, %r3, 0xffff		/* clean srr1 */
443	addis %r2, %r2, 0x4000		/* or in srr1<1> = 1 to flag pte
444					 * not found */
445isi1:
446	mtctr %r0			/* restore counter */
447	mtspr SPR_SRR1, %r2		/* set srr1 */
448	mfmsr %r0			/* get msr */
449	xoris %r0, %r0, 0x2		/* flip the msr<tgpr> bit */
450	mtcrf 0x80, %r3			/* restore CR0 */
451	mtmsr %r0			/* flip back to the native gprs */
452	ba EXC_ISI 			/* go to instr. access interrupt */
453
454CNAME(imisssize) = .-CNAME(imisstrap)
455
456/*
457 * G2 specific: data load TLB miss.
458 */
459	.globl	CNAME(dlmisstrap),CNAME(dlmisssize)
460CNAME(dlmisstrap):
461	mfspr %r2, SPR_HASH1		/* get first pointer */
462	addi %r1, 0, 8			/* load 8 for counter */
463	mfctr %r0			/* save counter */
464	mfspr %r3, SPR_DCMP		/* get first compare value */
465	addi %r2, %r2, -8		/* pre dec the pointer */
466dm0:
467	mtctr %r1			/* load counter */
468dm1:
469	lwzu %r1, 8(%r2)		/* get next pte */
470	cmp 0, 0, %r1, %r3		/* see if found pte */
471	bdnzf 2, dm1			/* dec count br if cmp ne and if
472					 * count not zero */
473	bne data_sec_hash		/* if not found set up second hash
474					 * or exit */
475	lwz %r1, +4(%r2)		/* load tlb entry lower-word */
476	mtctr %r0			/* restore counter */
477	mfspr %r0, SPR_DMISS		/* get the miss address for the tlbld */
478	mfspr %r3, SPR_SRR1		/* get the saved cr0 bits */
479	mtcrf 0x80, %r3			/* restore CR0 */
480	mtspr SPR_RPA, %r1		/* set the pte */
481	ori %r1, %r1, 0x100		/* set reference bit */
482	srwi %r1, %r1, 8		/* get byte 7 of pte */
483	tlbld %r0			/* load the dtlb */
484	stb %r1, +6(%r2)		/* update page table */
485	rfi				/* return to executing program */
486
487data_sec_hash:
488	andi. %r1, %r3, 0x0040		/* see if we have done second hash */
489	bne do_dsi			/* if so, go to DSI interrupt */
490	mfspr %r2, SPR_HASH2		/* get the second pointer */
491	ori %r3, %r3, 0x0040		/* change the compare value */
492	addi %r1, 0, 8			/* load 8 for counter */
493	addi %r2, %r2, -8		/* pre dec for update on load */
494	b dm0				/* try second hash */
495
496CNAME(dlmisssize) = .-CNAME(dlmisstrap)
497
498/*
499 *  G2 specific: data store TLB miss.
500 */
501	.globl	CNAME(dsmisstrap),CNAME(dsmisssize)
502CNAME(dsmisstrap):
503	mfspr %r2, SPR_HASH1		/* get first pointer */
504	addi %r1, 0, 8			/* load 8 for counter */
505	mfctr %r0			/* save counter */
506	mfspr %r3, SPR_DCMP		/* get first compare value */
507	addi %r2, %r2, -8		/* pre dec the pointer */
508ds0:
509	mtctr %r1			/* load counter */
510ds1:
511	lwzu %r1, 8(%r2)		/* get next pte */
512	cmp 0, 0, %r1, %r3		/* see if found pte */
513	bdnzf 2, ds1			/* dec count br if cmp ne and if
514					 * count not zero */
515	bne data_store_sec_hash		/* if not found set up second hash
516					 * or exit */
517	lwz %r1, +4(%r2)		/* load tlb entry lower-word */
518	andi. %r3, %r1, 0x80		/* check the C-bit */
519	beq data_store_chk_prot		/* if (C==0)
520					 *     go check protection modes */
521ds2:
522	mtctr %r0			/* restore counter */
523	mfspr %r0, SPR_DMISS		/* get the miss address for the tlbld */
524	mfspr %r3, SPR_SRR1		/* get the saved cr0 bits */
525	mtcrf 0x80, %r3			/* restore CR0 */
526	mtspr SPR_RPA, %r1		/* set the pte */
527	tlbld %r0			/* load the dtlb */
528	rfi				/* return to executing program */
529
530data_store_sec_hash:
531	andi. %r1, %r3, 0x0040		/* see if we have done second hash */
532	bne do_dsi			/* if so, go to DSI interrupt */
533	mfspr %r2, SPR_HASH2		/* get the second pointer */
534	ori %r3, %r3, 0x0040		/* change the compare value */
535	addi %r1, 0, 8			/* load 8 for counter */
536	addi %r2, %r2, -8		/* pre dec for update on load */
537	b ds0				/* try second hash */
538
539/* Check the protection before setting PTE(c-bit) */
540data_store_chk_prot:
541	rlwinm. %r3,%r1,30,0,1		/* test PP */
542	bge- chk0			/* if (PP == 00 or PP == 01)
543					 *     goto chk0: */
544	andi. %r3, %r1, 1		/* test PP[0] */
545	beq+ chk2			/* return if PP[0] == 0 */
546	b do_dsi_prot			/* else DSIp */
547chk0:
548	mfspr %r3,SPR_SRR1		/* get old msr */
549	andis. %r3,%r3,0x0008		/* test the KEY bit (SRR1-bit 12) */
550	beq chk2			/* if (KEY==0) goto chk2: */
551	b do_dsi_prot			/* else do_dsi_prot */
552chk2:
553	ori %r1, %r1, 0x180		/* set reference and change bit */
554	sth %r1, 6(%r2)			/* update page table */
555	b ds2				/* and back we go */
556
557/* Create a faked DSI interrupt as the address was not found */
558do_dsi:
559	mfspr %r3, SPR_SRR1		/* get srr1 */
560	rlwinm %r1,%r3,9,6,6		/* get srr1<flag> to bit 6 for
561					 * load/store, zero rest */
562	addis %r1, %r1, 0x4000		/* or in dsisr<1> = 1 to flag pte
563					 * not found */
564	b dsi1
565
566do_dsi_prot:
567	mfspr %r3, SPR_SRR1		/* get srr1 */
568	rlwinm %r1,%r3,9,6,6		/* get srr1<flag> to bit 6 for
569					   *load/store, zero rest */
570	addis %r1, %r1, 0x0800		/* or in dsisr<4> = 1 to flag prot
571					 * violation */
572
573dsi1:
574	mtctr %r0			/* restore counter */
575	andi. %r2, %r3, 0xffff		/* clear upper bits of srr1 */
576	mtspr SPR_SRR1, %r2		/* set srr1 */
577	mtspr SPR_DSISR, %r1		/* load the dsisr */
578	mfspr %r1, SPR_DMISS		/* get miss address */
579	rlwinm. %r2,%r2,0,31,31		/* test LE bit */
580	beq dsi2			/* if little endian then: */
581	xor %r1, %r1, 0x07		/* de-mung the data address */
582dsi2:
583	mtspr SPR_DAR, %r1		/* put in dar */
584	mfmsr %r0			/* get msr */
585	xoris %r0, %r0, 0x2		/* flip the msr<tgpr> bit */
586	mtcrf 0x80, %r3			/* restore CR0 */
587	mtmsr %r0			/* flip back to the native gprs */
588	ba EXC_DSI			/* branch to DSI interrupt */
589
590CNAME(dsmisssize) = .-CNAME(dsmisstrap)
591
592/*
593 * Similar to the above for DSI
594 * Has to handle BAT spills
595 * and standard pagetable spills
596 */
597	.globl	CNAME(dsitrap),CNAME(dsiend)
598CNAME(dsitrap):
599	mtsprg1	%r1			/* save SP */
600	GET_CPUINFO(%r1)
601	stw	%r28,(PC_DISISAVE+CPUSAVE_R28)(%r1)	/* free r28-r31 */
602	stw	%r29,(PC_DISISAVE+CPUSAVE_R29)(%r1)
603	stw	%r30,(PC_DISISAVE+CPUSAVE_R30)(%r1)
604	stw	%r31,(PC_DISISAVE+CPUSAVE_R31)(%r1)
605	mfsprg1	%r1			/* restore SP */
606	mfcr	%r29			/* save CR */
607	mfxer	%r30			/* save XER */
608	mtsprg2	%r30			/* in SPRG2 */
609	mfsrr1	%r31			/* test kernel mode */
610	mtcr	%r31
611	bt	17,1f			/* branch if PSL_PR is set */
612	mfdar	%r31			/* get fault address */
613	rlwinm	%r31,%r31,7,25,28	/* get segment * 8 */
614
615	/* get batu */
616	lwz	%r30,TRAP_TOCBASE(0)
617	lwz	%r30,CNAME(battable)@got(%r30)
618	add	%r31,%r30,%r31
619	lwz	%r30,0(%r31)
620	mtcr	%r30
621	bf	30,1f			/* branch if supervisor valid is
622					   false */
623	/* get batl */
624	lwz	%r31,4(%r31)
625/* We randomly use the highest two bat registers here */
626	mftb	%r28
627	andi.	%r28,%r28,1
628	bne	2f
629	mtdbatu	2,%r30
630	mtdbatl	2,%r31
631	b	3f
6322:
633	mtdbatu	3,%r30
634	mtdbatl	3,%r31
6353:
636	mfsprg2	%r30			/* restore XER */
637	mtxer	%r30
638	mtcr	%r29			/* restore CR */
639	mtsprg1	%r1
640	GET_CPUINFO(%r1)
641	lwz	%r28,(PC_DISISAVE+CPUSAVE_R28)(%r1)	/* restore r28-r31 */
642	lwz	%r29,(PC_DISISAVE+CPUSAVE_R29)(%r1)
643	lwz	%r30,(PC_DISISAVE+CPUSAVE_R30)(%r1)
644	lwz	%r31,(PC_DISISAVE+CPUSAVE_R31)(%r1)
645	mfsprg1	%r1
646	rfi				/* return to trapped code */
6471:
648	mflr	%r28			/* save LR (SP already saved) */
649
650	/* Jump to disitrap */
651	lwz	%r1, TRAP_GENTRAP(0)
652	addi	%r1, %r1, (disitrap - generictrap)
653	mtlr	%r1
654	blrl
655CNAME(dsiend):
656
657/*
658 * Preamble code for DSI/ISI traps
659 */
660disitrap:
661	/* Write the trap vector to SPRG3 by computing LR & 0xff00 */
662	mflr	%r1
663	andi.	%r1,%r1,0xff00
664	mtsprg3	%r1
665
666	GET_CPUINFO(%r1)
667	lwz	%r30,(PC_DISISAVE+CPUSAVE_R28)(%r1)
668	stw	%r30,(PC_TEMPSAVE+CPUSAVE_R28)(%r1)
669	lwz	%r31,(PC_DISISAVE+CPUSAVE_R29)(%r1)
670	stw	%r31,(PC_TEMPSAVE+CPUSAVE_R29)(%r1)
671	lwz	%r30,(PC_DISISAVE+CPUSAVE_R30)(%r1)
672	stw	%r30,(PC_TEMPSAVE+CPUSAVE_R30)(%r1)
673	lwz	%r31,(PC_DISISAVE+CPUSAVE_R31)(%r1)
674	stw	%r31,(PC_TEMPSAVE+CPUSAVE_R31)(%r1)
675	mfdar	%r30
676	mfdsisr	%r31
677	stw	%r30,(PC_TEMPSAVE+CPUSAVE_AIM_DAR)(%r1)
678	stw	%r31,(PC_TEMPSAVE+CPUSAVE_AIM_DSISR)(%r1)
679
680#ifdef KDB
681	/* Try to detect a kernel stack overflow */
682	mfsrr1	%r31
683	mtcr	%r31
684	bt	17,realtrap		/* branch is user mode */
685	mfsprg1	%r31			/* get old SP */
686	clrrwi	%r31,%r31,12		/* Round SP down to nearest page */
687	sub.	%r30,%r31,%r30		/* SP - DAR */
688	bge	1f
689	neg	%r30,%r30		/* modulo value */
6901:	cmplwi	%cr0,%r30,4096		/* is DAR within a page of SP? */
691	bge	%cr0,realtrap		/* no, too far away. */
692
693	/* Now convert this DSI into a DDB trap.  */
694	GET_CPUINFO(%r1)
695	lwz	%r30,(PC_TEMPSAVE+CPUSAVE_AIM_DAR)(%r1) /* get DAR */
696	stw	%r30,(PC_DBSAVE  +CPUSAVE_AIM_DAR)(%r1) /* save DAR */
697	lwz	%r31,(PC_TEMPSAVE+CPUSAVE_AIM_DSISR)(%r1) /* get DSISR */
698	stw	%r31,(PC_DBSAVE  +CPUSAVE_AIM_DSISR)(%r1) /* save DSISR */
699	lwz	%r30,(PC_DISISAVE+CPUSAVE_R28)(%r1) /* get  r28 */
700	stw	%r30,(PC_DBSAVE  +CPUSAVE_R28)(%r1) /* save r28 */
701	lwz	%r31,(PC_DISISAVE+CPUSAVE_R29)(%r1) /* get  r29 */
702	stw	%r31,(PC_DBSAVE  +CPUSAVE_R29)(%r1) /* save r29 */
703	lwz	%r30,(PC_DISISAVE+CPUSAVE_R30)(%r1) /* get  r30 */
704	stw	%r30,(PC_DBSAVE  +CPUSAVE_R30)(%r1) /* save r30 */
705	lwz	%r31,(PC_DISISAVE+CPUSAVE_R31)(%r1) /* get  r31 */
706	stw	%r31,(PC_DBSAVE  +CPUSAVE_R31)(%r1) /* save r31 */
707	b	dbtrap
708#endif
709
710	/* XXX need stack probe here */
711realtrap:
712/* Test whether we already had PR set */
713	mfsrr1	%r1
714	mtcr	%r1
715	mfsprg1	%r1			/* restore SP (might have been
716					   overwritten) */
717	bf	17,k_trap		/* branch if PSL_PR is false */
718	GET_CPUINFO(%r1)
719	lwz	%r1,PC_CURPCB(%r1)
720	RESTORE_KERN_SRS(%r30,%r31)	/* enable kernel mapping */
721	b	s_trap
722
723/*
724 * generictrap does some standard setup for trap handling to minimize
725 * the code that need be installed in the actual vectors. It expects
726 * the following conditions.
727 *
728 * R1 - Trap vector = LR & (0xff00 | R1)
729 * SPRG1 - Original R1 contents
730 * SPRG2 - Original LR
731 */
732
733	.globl	CNAME(generictrap64)
734generictrap64:
735	mtsprg3	%r31
736	mfmsr	%r31
737	clrldi	%r31,%r31,1
738	mtmsrd	%r31
739	mfsprg3	%r31
740	isync
741
742	.globl	CNAME(generictrap)
743generictrap:
744	/* Save R1 for computing the exception vector */
745	mtsprg3 %r1
746
747	/* Save interesting registers */
748	GET_CPUINFO(%r1)
749	stw	%r28,(PC_TEMPSAVE+CPUSAVE_R28)(%r1)	/* free r28-r31 */
750	stw	%r29,(PC_TEMPSAVE+CPUSAVE_R29)(%r1)
751	stw	%r30,(PC_TEMPSAVE+CPUSAVE_R30)(%r1)
752	stw	%r31,(PC_TEMPSAVE+CPUSAVE_R31)(%r1)
753	mfsprg1	%r1			/* restore SP, in case of branch */
754	mfsprg2	%r28			/* save LR */
755	mfcr	%r29			/* save CR */
756
757	/* Compute the exception vector from the link register */
758	mfsprg3 %r31
759	ori	%r31,%r31,0xff00
760	mflr	%r30
761	and	%r30,%r30,%r31
762	mtsprg3	%r30
763
764	/* Test whether we already had PR set */
765	mfsrr1	%r31
766	mtcr	%r31
767
768s_trap:
769	bf	17,k_trap		/* branch if PSL_PR is false */
770	GET_CPUINFO(%r1)
771u_trap:
772	lwz	%r1,PC_CURPCB(%r1)
773	RESTORE_KERN_SRS(%r30,%r31)	/* enable kernel mapping */
774
775/*
776 * Now the common trap catching code.
777 */
778k_trap:
779	FRAME_SETUP(PC_TEMPSAVE)
780	/* Restore USER_SR */
781	GET_CPUINFO(%r30)
782	lwz	%r30,PC_CURPCB(%r30)
783	lwz	%r30,PCB_AIM_USR_VSID(%r30)
784	mtsr	USER_SR,%r30; sync; isync
785/* Call C interrupt dispatcher: */
786trapagain:
787	addi	%r3,%r1,8
788	bl	CNAME(powerpc_interrupt)
789	.globl	CNAME(trapexit)		/* backtrace code sentinel */
790CNAME(trapexit):
791
792/* Disable interrupts: */
793	mfmsr	%r3
794	andi.	%r3,%r3,~PSL_EE@l
795	mtmsr	%r3
796	isync
797/* Test AST pending: */
798	lwz	%r5,FRAME_SRR1+8(%r1)
799	mtcr	%r5
800	bf	17,1f			/* branch if PSL_PR is false */
801
802	GET_CPUINFO(%r3)		/* get per-CPU pointer */
803	lwz	%r4, TD_FLAGS(%r2)	/* get thread flags value
804					 * (r2 is curthread) */
805	lis	%r5, (TDF_ASTPENDING|TDF_NEEDRESCHED)@h
806	ori	%r5,%r5, (TDF_ASTPENDING|TDF_NEEDRESCHED)@l
807	and.	%r4,%r4,%r5
808	beq	1f
809	mfmsr	%r3			/* re-enable interrupts */
810	ori	%r3,%r3,PSL_EE@l
811	mtmsr	%r3
812	isync
813	addi	%r3,%r1,8
814	bl	CNAME(ast)
815	.globl	CNAME(asttrapexit)	/* backtrace code sentinel #2 */
816CNAME(asttrapexit):
817	b	trapexit		/* test ast ret value ? */
8181:
819	FRAME_LEAVE(PC_TEMPSAVE)
820
821	.globl	CNAME(rfi_patch1)	/* replace rfi with rfid on ppc64 */
822CNAME(rfi_patch1):
823	rfi
824
825	.globl	CNAME(rfid_patch)
826CNAME(rfid_patch):
827	rfid
828
829#if defined(KDB)
830/*
831 * Deliberate entry to dbtrap
832 */
833	.globl	CNAME(breakpoint)
834CNAME(breakpoint):
835	mtsprg1	%r1
836	mfmsr	%r3
837	mtsrr1	%r3
838	andi.	%r3,%r3,~(PSL_EE|PSL_ME)@l
839	mtmsr	%r3			/* disable interrupts */
840	isync
841	GET_CPUINFO(%r3)
842	stw	%r28,(PC_DBSAVE+CPUSAVE_R28)(%r3)
843	stw	%r29,(PC_DBSAVE+CPUSAVE_R29)(%r3)
844	stw	%r30,(PC_DBSAVE+CPUSAVE_R30)(%r3)
845	stw	%r31,(PC_DBSAVE+CPUSAVE_R31)(%r3)
846	mflr	%r28
847	li	%r29,EXC_BPT
848	mtlr	%r29
849	mfcr	%r29
850	mtsrr0	%r28
851
852/*
853 * Now the kdb trap catching code.
854 */
855dbtrap:
856	/* Write the trap vector to SPRG3 by computing LR & 0xff00 */
857	mflr	%r1
858	andi.	%r1,%r1,0xff00
859	mtsprg3	%r1
860
861	lwz	%r1,TRAP_TOCBASE(0)		/* get new SP */
862	lwz	%r1,trapstk@got(%r1)
863	addi	%r1,%r1,TRAPSTKSZ-16
864
865	FRAME_SETUP(PC_DBSAVE)
866/* Call C trap code: */
867	addi	%r3,%r1,8
868	bl	CNAME(db_trap_glue)
869	or.	%r3,%r3,%r3
870	bne	dbleave
871/* This wasn't for KDB, so switch to real trap: */
872	lwz	%r3,FRAME_EXC+8(%r1)	/* save exception */
873	GET_CPUINFO(%r4)
874	stw	%r3,(PC_DBSAVE+CPUSAVE_R31)(%r4)
875	FRAME_LEAVE(PC_DBSAVE)
876	mtsprg1	%r1			/* prepare for entrance to realtrap */
877	GET_CPUINFO(%r1)
878	stw	%r28,(PC_TEMPSAVE+CPUSAVE_R28)(%r1)
879	stw	%r29,(PC_TEMPSAVE+CPUSAVE_R29)(%r1)
880	stw	%r30,(PC_TEMPSAVE+CPUSAVE_R30)(%r1)
881	stw	%r31,(PC_TEMPSAVE+CPUSAVE_R31)(%r1)
882	mflr	%r28
883	mfcr	%r29
884	lwz	%r31,(PC_DBSAVE+CPUSAVE_R31)(%r1)
885	mtsprg3	%r31			/* SPRG3 was clobbered by FRAME_LEAVE */
886	mfsprg1	%r1
887	b	realtrap
888dbleave:
889	FRAME_LEAVE(PC_DBSAVE)
890	.globl	CNAME(rfi_patch2)	/* replace rfi with rfid on ppc64 */
891CNAME(rfi_patch2):
892	rfi
893
894/*
895 * In case of KDB we want a separate trap catcher for it
896 */
897	.globl	CNAME(dblow),CNAME(dbend)
898CNAME(dblow):
899	mtsprg1	%r1			/* save SP */
900	mtsprg2	%r29			/* save r29 */
901	mfcr	%r29			/* save CR in r29 */
902	mfsrr1	%r1
903	mtcr	%r1
904	bf	17,1f			/* branch if privileged */
905	/* Unprivileged case */
906	mtcr	%r29			/* put the condition register back */
907        mfsprg2	%r29			/* ... and r29 */
908        mflr	%r1			/* save LR */
909	mtsprg2 %r1			/* And then in SPRG2 */
910
911	lwz	%r1, TRAP_ENTRY(0)	/* Get branch address */
912	mtlr	%r1
913	li	%r1, 0			/* How to get the vector from LR */
914	blrl				/* LR & (0xff00 | r1) is exception # */
9151:
916	/* Privileged, so drop to KDB */
917	GET_CPUINFO(%r1)
918	stw	%r28,(PC_DBSAVE+CPUSAVE_R28)(%r1)	/* free r28 */
919        mfsprg2	%r28				/* r29 holds cr...  */
920        stw	%r28,(PC_DBSAVE+CPUSAVE_R29)(%r1)	/* free r29 */
921        stw	%r30,(PC_DBSAVE+CPUSAVE_R30)(%r1)	/* free r30 */
922        stw	%r31,(PC_DBSAVE+CPUSAVE_R31)(%r1)	/* free r31 */
923        mflr	%r28					/* save LR */
924
925	/* Jump to dbtrap */
926	lwz	%r1, TRAP_GENTRAP(0)
927	addi	%r1, %r1, (dbtrap - generictrap)
928	mtlr	%r1
929	blrl
930CNAME(dbend):
931#endif /* KDB */
932