xref: /titanic_41/usr/src/uts/sun4v/ml/mach_interrupt.s (revision 4496171313bed39e96f21bc2f9faf2868e267ae3)
1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21/*
22 * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
23 * Use is subject to license terms.
24 */
25
26#pragma ident	"%Z%%M%	%I%	%E% SMI"
27
28#if defined(lint)
29#include <sys/types.h>
30#include <sys/thread.h>
31#else	/* lint */
32#include "assym.h"
33#endif	/* lint */
34
35#include <sys/asm_linkage.h>
36#include <sys/machthread.h>
37#include <sys/machcpuvar.h>
38#include <sys/intreg.h>
39#include <sys/cmn_err.h>
40#include <sys/ftrace.h>
41#include <sys/machasi.h>
42#include <sys/scb.h>
43#include <sys/error.h>
44#define	INTR_REPORT_SIZE	64
45
46#ifdef TRAPTRACE
47#include <sys/traptrace.h>
48#endif /* TRAPTRACE */
49
50#if defined(lint)
51
52void
53cpu_mondo(void)
54{}
55
56#else	/* lint */
57
58
59/*
60 * (TT 0x7c, TL>0) CPU Mondo Queue Handler
61 *	Globals are the Interrupt Globals.
62 */
63	ENTRY_NP(cpu_mondo)
64	!
65	!	Register Usage:-
66	!	%g5	PC for fasttrap TL>0 handler
67	!	%g1	arg 1
68	!	%g2	arg 2
69	!	%g3	queue base VA
70	!	%g4 	queue size mask
71	!	%g6	head ptr
72	!	%g7	tail ptr
73	mov	CPU_MONDO_Q_HD, %g3
74	ldxa	[%g3]ASI_QUEUE, %g6	! %g6 = head ptr
75	mov	CPU_MONDO_Q_TL, %g4
76	ldxa	[%g4]ASI_QUEUE, %g7	! %g7 = tail ptr
77	cmp	%g6, %g7
78	be,pn	%xcc, 0f		! head == tail
79	nop
80
81	CPU_ADDR(%g1,%g2)
82	add	%g1, CPU_MCPU, %g2
83	ldx	[%g2 + MCPU_CPU_Q_BASE], %g3	! %g3 = queue base PA
84	ldx	[%g2 + MCPU_CPU_Q_SIZE], %g4	! queue size
85	sub	%g4, 1, %g4		! %g4 = queue size mask
86
87	! Load interrupt receive data registers 1 and 2 to fetch
88	! the arguments for the fast trap handler.
89	!
90	! XXX - Since the data words in the interrupt report are not defined yet
91	! we assume that the consective words contain valid data and preserve
92	! sun4u's xcall mondo arguments.
93	! Register usage:
94	!	%g5	PC for fasttrap TL>0 handler
95	!	%g1	arg 1
96	!	%g2	arg 2
97
98	ldxa	[%g3 + %g6]ASI_MEM, %g5	! get PC from q base + head
99	add	%g6, 0x8, %g6		! inc head
100	ldxa	[%g3 + %g6]ASI_MEM, %g1 ! read data word 1
101	add	%g6, 0x8, %g6		! inc head
102	ldxa	[%g3 + %g6]ASI_MEM, %g2	! read data word 2
103	add	%g6, (INTR_REPORT_SIZE - 16) , %g6 ! inc head to next record
104	and	%g6, %g4, %g6 		! and size mask for wrap around
105	mov	CPU_MONDO_Q_HD, %g3
106	stxa	%g6, [%g3]ASI_QUEUE	! store head pointer
107	membar	#Sync
108
109#ifdef TRAPTRACE
110	TRACE_PTR(%g4, %g6)
111	GET_TRACE_TICK(%g6)
112	stxa	%g6, [%g4 + TRAP_ENT_TICK]%asi
113	TRACE_SAVE_TL_GL_REGS(%g4, %g6)
114	rdpr	%tt, %g6
115	stha	%g6, [%g4 + TRAP_ENT_TT]%asi
116	rdpr	%tpc, %g6
117	stna	%g6, [%g4 + TRAP_ENT_TPC]%asi
118	rdpr	%tstate, %g6
119	stxa	%g6, [%g4 + TRAP_ENT_TSTATE]%asi
120	stna	%sp, [%g4 + TRAP_ENT_SP]%asi
121	stna	%g5, [%g4 + TRAP_ENT_TR]%asi	! pc of the TL>0 handler
122	stna	%g1, [%g4 + TRAP_ENT_F1]%asi	! arg1
123	stna	%g2, [%g4 + TRAP_ENT_F3]%asi	! arg2
124	mov	CPU_MONDO_Q_HD, %g6
125	ldxa	[%g6]ASI_QUEUE, %g6		! new head offset
126	stna	%g6, [%g4 + TRAP_ENT_F2]%asi
127	stna	%g7, [%g4 + TRAP_ENT_F4]%asi	! tail offset
128	TRACE_NEXT(%g4, %g6, %g3)
129#endif /* TRAPTRACE */
130
131	/*
132	 * For now catch invalid PC being passed via cpu_mondo queue
133	 */
134	set	KERNELBASE, %g4
135	cmp	%g5, %g4
136	bl,a,pn	%xcc, 1f		! branch if bad %pc
137	nop
138
139	jmp	%g5			! jump to traphandler
140	nop
1411:
142	! invalid trap handler, discard it for now
143	set	cpu_mondo_inval, %g4
144	ldx	[%g4], %g5
145	inc	%g5
146	stx	%g5, [%g4]
1470:
148	retry
149	/* Never Reached */
150	SET_SIZE(cpu_mondo)
151
152#endif /* lint */
153
154#if defined(lint)
155
156void
157dev_mondo(void)
158{}
159
160#else	/* lint */
161
162
163/*
164 * (TT 0x7d, TL>0) Dev Mondo Queue Handler
165 *	Globals are the Interrupt Globals.
166 * We only process one interrupt at a time causing us to keep
167 * taking this trap till the queue is empty.
168 * We really should drain the whole queue for better performance
169 * but this will do for now.
170 */
171	ENTRY_NP(dev_mondo)
172	!
173	!	Register Usage:-
174	!	%g5	PC for fasttrap TL>0 handler
175	!	%g1	arg 1
176	!	%g2	arg 2
177	!	%g3	queue base PA
178	!	%g4 	queue size mask
179	!	%g6	head ptr
180	!	%g7	tail ptr
181	mov	DEV_MONDO_Q_HD, %g3
182	ldxa	[%g3]ASI_QUEUE, %g6	! %g6 = head ptr
183	mov	DEV_MONDO_Q_TL, %g4
184	ldxa	[%g4]ASI_QUEUE, %g7	! %g7 = tail ptr
185	cmp	%g6, %g7
186	be,pn	%xcc, 0f		! head == tail
187	nop
188
189	CPU_ADDR(%g1,%g2)
190	add	%g1, CPU_MCPU, %g2
191	ldx	[%g2 + MCPU_DEV_Q_BASE], %g3	! %g3 = queue base PA
192
193	! Register usage:
194	!	%g5 - inum
195	!	%g1 - cpu struct pointer used below in TRAPTRACE
196	!
197	ldxa	[%g3 + %g6]ASI_MEM, %g5	! get inum from q base + head
198
199	!
200	! We verify that inum is valid ( < MAXVNUM). If it is greater
201	! than MAXVNUM, we let setvecint_tl1 take care of it.
202	!
203	set	MAXIVNUM, %g4
204	cmp	%g5, %g4
205	bgeu,a,pn	%xcc, 1f
206	ldx	[%g2 + MCPU_DEV_Q_SIZE], %g4	! queue size - delay slot
207
208	!
209	!	Copy 64-byte payload to the *iv_payload if it is not NULL
210	!
211	set	intr_vec_table, %g1		! %g1 = intr_vec_table
212	sll	%g5, CPTRSHIFT, %g7		! %g7 = offset to inum entry
213						!       in the intr_vec_table
214	add	%g1, %g7, %g7			! %g7 = &intr_vec_table[inum]
215	ldn	[%g7], %g1			! %g1 = ptr to intr_vec_t (iv)
216	ldx	[%g1 + IV_PAYLOAD_BUF], %g1	! %g1 = iv->iv_payload_buf
217	brz,a,pt	%g1, 1f			! if it is NULL
218	ldx	[%g2 + MCPU_DEV_Q_SIZE], %g4	! queue size - delay slot
219
220	!
221	!	Now move 64 byte payload from mondo queue to buf
222	!
223	mov	%g6, %g7			! %g7 = head ptr
224	ldxa	[%g3 + %g7]ASI_MEM, %g4
225	stx	%g4, [%g1 + 0]			! byte 0 - 7
226	add	%g7, 8, %g7
227	ldxa	[%g3 + %g7]ASI_MEM, %g4
228	stx	%g4, [%g1 + 8]			! byte 8 - 15
229	add	%g7, 8, %g7
230	ldxa	[%g3 + %g7]ASI_MEM, %g4
231	stx	%g4, [%g1 + 16]			! byte 16 - 23
232	add	%g7, 8, %g7
233	ldxa	[%g3 + %g7]ASI_MEM, %g4
234	stx	%g4, [%g1 + 24]			! byte 24 - 31
235	add	%g7, 8, %g7
236	ldxa	[%g3 + %g7]ASI_MEM, %g4
237	stx	%g4, [%g1 + 32]			! byte 32 - 39
238	add	%g7, 8, %g7
239	ldxa	[%g3 + %g7]ASI_MEM, %g4
240	stx	%g4, [%g1 + 40]			! byte 40 - 47
241	add	%g7, 8, %g7
242	ldxa	[%g3 + %g7]ASI_MEM, %g4
243	stx	%g4, [%g1 + 48]			! byte 48 - 55
244	add	%g7, 8, %g7
245	ldxa	[%g3 + %g7]ASI_MEM, %g4
246	stx	%g4, [%g1 + 56]			! byte 56 - 63
247	ldx	[%g2 + MCPU_DEV_Q_SIZE], %g4	! queue size
248
2491:	sub	%g4, 1, %g4		! %g4 = queue size mask
250	add	%g6, INTR_REPORT_SIZE , %g6 ! inc head to next record
251	and	%g6, %g4, %g6 		! and mask for wrap around
252	mov	DEV_MONDO_Q_HD, %g3
253	stxa	%g6, [%g3]ASI_QUEUE	! increment head offset
254	membar	#Sync
255
256#ifdef TRAPTRACE
257	TRACE_PTR(%g4, %g6)
258	GET_TRACE_TICK(%g6)
259	stxa	%g6, [%g4 + TRAP_ENT_TICK]%asi
260	TRACE_SAVE_TL_GL_REGS(%g4, %g6)
261	rdpr	%tt, %g6
262	stha	%g6, [%g4 + TRAP_ENT_TT]%asi
263	rdpr	%tpc, %g6
264	stna	%g6, [%g4 + TRAP_ENT_TPC]%asi
265	rdpr	%tstate, %g6
266	stxa	%g6, [%g4 + TRAP_ENT_TSTATE]%asi
267	! move head to sp
268	ldx	[%g2 + MCPU_DEV_Q_BASE], %g6
269	stna	%g6, [%g4 + TRAP_ENT_SP]%asi	! Device Queue Base PA
270	stna	%g5, [%g4 + TRAP_ENT_TR]%asi	! Inum
271	mov	DEV_MONDO_Q_HD, %g6
272	ldxa	[%g6]ASI_QUEUE, %g6		! New head offset
273	stna	%g6, [%g4 + TRAP_ENT_F1]%asi
274#ifdef __sparcv9
275	ldx	[%g2 + MCPU_DEV_Q_SIZE], %g6
276	stna	%g6, [%g4 + TRAP_ENT_F2]%asi	! Q Size
277	stna	%g7, [%g4 + TRAP_ENT_F3]%asi	! tail offset
278	stna	%g0, [%g4 + TRAP_ENT_F4]%asi
279#endif
280	TRACE_NEXT(%g4, %g6, %g3)
281#endif /* TRAPTRACE */
282
283	!
284	! setvecint_tl1 will do all the work, and finish with a retry
285	!
286	ba,pt	%xcc, setvecint_tl1
287	mov	%g5, %g1		! setvecint_tl1 expects inum in %g1
288
2890:	retry
290
291	/* Never Reached */
292	SET_SIZE(dev_mondo)
293#endif /* lint */
294
295#if defined(lint)
296uint64_t cpu_mondo_inval;
297#else /* lint */
298	.seg	".data"
299	.global	cpu_mondo_inval
300	.align	8
301cpu_mondo_inval:
302	.skip	8
303
304	.seg	".text"
305#endif	/* lint */
306
307
308#if defined(lint)
309
310void
311resumable_error(void)
312{}
313
314#else	/* lint */
315
316/*
317 * (TT 0x7e, TL>0) Resumeable Error Queue Handler
318 *	We keep a shadow copy of the queue in kernel buf.
319 *	Read the resumable queue head and tail offset
320 *	If there are entries on the queue, move them to
321 *	the kernel buf, which is next to the resumable
322 *	queue in the memory. Call C routine to process.
323 */
324	ENTRY_NP(resumable_error)
325	mov	CPU_RQ_HD, %g4
326	ldxa	[%g4]ASI_QUEUE, %g2		! %g2 = Q head offset
327	mov	CPU_RQ_TL, %g4
328	ldxa	[%g4]ASI_QUEUE, %g3		! %g3 = Q tail offset
329	mov	%g2, %g6			! save head in %g2
330
331	cmp	%g6, %g3
332	be,pn	%xcc, 0f			! head == tail
333	nop
334
335	CPU_ADDR(%g1, %g4)			! %g1 = cpu struct addr
336
3372:	set	CPU_RQ_BASE_OFF, %g4
338	ldx	[%g1 + %g4], %g4		! %g4 = queue base PA
339	add	%g6, %g4, %g4			! %g4 = PA of ER in Q
340	set	CPU_RQ_SIZE, %g7
341	add	%g4, %g7, %g7			! %g7=PA of ER in kernel buf
342
343	ldxa	[%g7]ASI_MEM, %g5		! %g5=first 8 byte of ER buf
344	cmp	0, %g5
345	bne,pn	%xcc, 1f			! first 8 byte is not 0
346	nop
347
348	/* Now we can move 64 bytes from queue to buf */
349	set	0, %g5
350	ldxa	[%g4 + %g5]ASI_MEM, %g1
351	stxa	%g1, [%g7 + %g5]ASI_MEM		! byte 0 - 7
352	add	%g5, 8, %g5
353	ldxa	[%g4 + %g5]ASI_MEM, %g1
354	stxa	%g1, [%g7 + %g5]ASI_MEM		! byte 8 - 15
355	add	%g5, 8, %g5
356	ldxa	[%g4 + %g5]ASI_MEM, %g1
357	stxa	%g1, [%g7 + %g5]ASI_MEM		! byte 16 - 23
358	add	%g5, 8, %g5
359	ldxa	[%g4 + %g5]ASI_MEM, %g1
360	stxa	%g1, [%g7 + %g5]ASI_MEM		! byte 24 - 31
361	add	%g5, 8, %g5
362	ldxa	[%g4 + %g5]ASI_MEM, %g1
363	stxa	%g1, [%g7 + %g5]ASI_MEM		! byte 32 - 39
364	add	%g5, 8, %g5
365	ldxa	[%g4 + %g5]ASI_MEM, %g1
366	stxa	%g1, [%g7 + %g5]ASI_MEM		! byte 40 - 47
367	add	%g5, 8, %g5
368	ldxa	[%g4 + %g5]ASI_MEM, %g1
369	stxa	%g1, [%g7 + %g5]ASI_MEM		! byte 48 - 55
370	add	%g5, 8, %g5
371	ldxa	[%g4 + %g5]ASI_MEM, %g1
372	stxa	%g1, [%g7 + %g5]ASI_MEM		! byte 56 - 63
373
374	set	CPU_RQ_SIZE, %g5		! %g5 = queue size
375	sub	%g5, 1, %g5			! %g5 = queu size mask
376
377	add	%g6, Q_ENTRY_SIZE, %g6		! increment q head to next
378	and	%g6, %g5, %g6			! size mask for warp around
379	cmp	%g6, %g3			! head == tail ??
380
381	bne,pn	%xcc, 2b			! still have more to process
382	nop
383
384	/*
385	 * head equals to tail now, we can update the queue head
386	 * and call sys_trap
387	 */
388	mov	CPU_RQ_HD, %g4
389	stxa	%g6, [%g4]ASI_QUEUE		! update head offset
390
391	/*
392	 * Call sys_trap at PIL 14 unless we're already at PIL 15. %g2.l is
393	 * head offset(arg2) and %g3 is tail
394	 * offset(arg3).
395	 */
396	set	process_resumable_error, %g1
397	rdpr	%pil, %g4
398	cmp	%g4, PIL_14
399	ba	sys_trap
400	  movl	%icc, PIL_14, %g4
401
402	/*
403	 * We are here because the C routine is not able to process
404	 * errors in time. So the first 8 bytes of ER in buf has not
405	 * been cleared. We update head to tail and call sys_trap to
406	 * print out an error message
407	 */
408
4091:	mov	CPU_RQ_HD, %g4
410	stxa	%g3, [%g4]ASI_QUEUE		! set head equal to tail
411
412	/*
413	 * Set %g2 to %g6, which is current head offset. %g2
414	 * is arg2 of the C routine. %g3 is the tail offset,
415	 * which is arg3 of the C routine.
416	 * Call rq_overflow at PIL 14 unless we're already at PIL 15.
417	 */
418	mov	%g6, %g2
419	set	rq_overflow, %g1
420	rdpr	%pil, %g4
421	cmp	%g4, PIL_14
422	ba	sys_trap
423	  movl	%icc, PIL_14, %g4
424
4250:	retry
426
427	/*NOTREACHED*/
428	SET_SIZE(resumable_error)
429#endif /* lint */
430
431#if defined(lint)
432
433void
434nonresumable_error(void)
435{}
436
437#else	/* lint */
438
439/*
440 * (TT 0x7f, TL>0) Non-resumeable Error Queue Handler
441 *	We keep a shadow copy of the queue in kernel buf.
442 *	Read non-resumable queue head and tail offset
443 *	If there are entries on the queue, move them to
444 *	the kernel buf, which is next to the non-resumable
445 *	queue in the memory. Call C routine to process.
446 */
447	ENTRY_NP(nonresumable_error)
448	mov	CPU_NRQ_HD, %g4
449	ldxa	[%g4]ASI_QUEUE, %g2		! %g2 = Q head offset
450	mov	CPU_NRQ_TL, %g4
451	ldxa	[%g4]ASI_QUEUE, %g3		! %g3 = Q tail offset
452
453	cmp	%g2, %g3
454	be,pn	%xcc, 0f			! head == tail
455	nop
456
457	/* force %gl to 1 as sys_trap requires */
458	wrpr	%g0, 1, %gl
459	mov	CPU_NRQ_HD, %g4
460	ldxa	[%g4]ASI_QUEUE, %g2		! %g2 = Q head offset
461	mov	CPU_NRQ_TL, %g4
462	ldxa	[%g4]ASI_QUEUE, %g3		! %g3 = Q tail offset
463	mov	%g2, %g6			! save head in %g2
464
465	CPU_PADDR(%g1, %g4)			! %g1 = cpu struct paddr
466
4672:	set	CPU_NRQ_BASE_OFF, %g4
468	ldxa	[%g1 + %g4]ASI_MEM, %g4		! %g4 = queue base PA
469	add	%g6, %g4, %g4			! %g4 = PA of ER in Q
470	set	CPU_NRQ_SIZE, %g7
471	add	%g4, %g7, %g7			! %g7 = PA of ER in kernel buf
472
473	ldxa	[%g7]ASI_MEM, %g5		! %g5 = first 8 byte of ER buf
474	cmp	0, %g5
475	bne,pn	%xcc, 1f			! first 8 byte is not 0
476	nop
477
478	/* Now we can move 64 bytes from queue to buf */
479	set	0, %g5
480	ldxa	[%g4 + %g5]ASI_MEM, %g1
481	stxa	%g1, [%g7 + %g5]ASI_MEM		! byte 0 - 7
482	add	%g5, 8, %g5
483	ldxa	[%g4 + %g5]ASI_MEM, %g1
484	stxa	%g1, [%g7 + %g5]ASI_MEM		! byte 8 - 15
485	add	%g5, 8, %g5
486	ldxa	[%g4 + %g5]ASI_MEM, %g1
487	stxa	%g1, [%g7 + %g5]ASI_MEM		! byte 16 - 23
488	add	%g5, 8, %g5
489	ldxa	[%g4 + %g5]ASI_MEM, %g1
490	stxa	%g1, [%g7 + %g5]ASI_MEM		! byte 24 - 31
491	add	%g5, 8, %g5
492	ldxa	[%g4 + %g5]ASI_MEM, %g1
493	stxa	%g1, [%g7 + %g5]ASI_MEM		! byte 32 - 39
494	add	%g5, 8, %g5
495	ldxa	[%g4 + %g5]ASI_MEM, %g1
496	stxa	%g1, [%g7 + %g5]ASI_MEM		! byte 40 - 47
497	add	%g5, 8, %g5
498	ldxa	[%g4 + %g5]ASI_MEM, %g1
499	stxa	%g1, [%g7 + %g5]ASI_MEM		! byte 48 - 55
500	add	%g5, 8, %g5
501	ldxa	[%g4 + %g5]ASI_MEM, %g1
502	stxa	%g1, [%g7 + %g5]ASI_MEM		! byte 56 - 63
503
504	set	CPU_NRQ_SIZE, %g5		! %g5 = queue size
505	sub	%g5, 1, %g5			! %g5 = queu size mask
506
507	add	%g6, Q_ENTRY_SIZE, %g6		! increment q head to next
508	and	%g6, %g5, %g6			! size mask for warp around
509	cmp	%g6, %g3			! head == tail ??
510
511	bne,pn	%xcc, 2b			! still have more to process
512	nop
513
514	/*
515	 * head equals to tail now, we can update the queue head
516	 * and call sys_trap
517	 */
518	mov	CPU_NRQ_HD, %g4
519	stxa	%g6, [%g4]ASI_QUEUE		! update head offset
520
521	/*
522	 * Call sys_trap. %g2 is TL(arg2), %g3 is head and tail
523	 * offset(arg3).
524	 * %g3 looks like following:
525	 *	+--------------------+--------------------+
526	 *	|   tail offset      |    head offset     |
527	 *	+--------------------+--------------------+
528	 *	63                 32 31                 0
529	 *
530	 * Run at PIL 14 unless we're already at PIL 15.
531	 */
532	sllx	%g3, 32, %g3			! %g3.h = tail offset
533	or	%g3, %g2, %g3			! %g3.l = head offset
534	rdpr	%tl, %g2			! %g2 = current tl
535
536	/*
537	 * Now check if the first error that sent us here was caused
538	 * in user's SPILL/FILL trap. If it was, we call sys_trap to
539	 * kill the user process. Several considerations:
540	 * - If multiple nonresumable errors happen, we only check the
541	 *   first one. Nonresumable errors cause system either panic
542	 *   or kill the user process. So the system has already
543	 *   panic'ed or killed user process after processing the first
544	 *   error. Therefore, no need to check if other error packet
545	 *   for this type of error.
546	 * - Errors happen in user's SPILL/FILL trap will bring us at
547	 *   TL = 2.
548	 * - We need to lower TL to 1 to get the trap type and tstate.
549	 *   We don't go back to TL = 2 so no need to save states.
550	 */
551	cmp	%g2, 2
552	bne,pt	%xcc, 3f			! if tl != 2
553	nop
554	/* Check to see if the trap pc is in a window spill/fill handling */
555	rdpr	%tpc, %g4
556	/* tpc should be in the trap table */
557	set	trap_table, %g5
558	cmp	%g4, %g5
559	blu,pt	%xcc, 3f
560	nop
561	set	etrap_table, %g5
562	cmp	%g4, %g5
563	bgeu,pt	%xcc, 3f
564	nop
565	/* Set tl to 1 in order to read tt[1] and tstate[1] */
566	wrpr	%g0, 1, %tl
567	rdpr	%tt, %g4			! %g4 = tt[1]
568	/* Check if tt[1] is a window trap */
569	and	%g4, WTRAP_TTMASK, %g4
570	cmp	%g4, WTRAP_TYPE
571	bne,pt	%xcc, 3f
572	nop
573	rdpr	%tstate, %g5			! %g5 = tstate[1]
574	btst	TSTATE_PRIV, %g5
575	bnz	%xcc, 3f			! Is it from user code?
576	nop
577	/*
578	 * Now we know the error happened in user's SPILL/FILL trap.
579	 * Turn on the user spill/fill flag in %g2
580	 */
581	mov	1, %g4
582	sllx	%g4, ERRH_U_SPILL_FILL_SHIFT, %g4
583	or	%g2, %g4, %g2			! turn on flag in %g2
584
5853:	sub	%g2, 1, %g2			! %g2.l = previous tl
586
587	set	process_nonresumable_error, %g1
588	rdpr	%pil, %g4
589	cmp	%g4, PIL_14
590	ba	sys_trap
591	  movl	%icc, PIL_14, %g4
592
593	/*
594	 * We are here because the C routine is not able to process
595	 * errors in time. So the first 8 bytes of ER in buf has not
596	 * been cleared. We call sys_trap to panic.
597	 * Run at PIL 14 unless we're already at PIL 15.
598	 */
5991:	set	nrq_overflow, %g1
600	rdpr	%pil, %g4
601	cmp	%g4, PIL_14
602	ba	sys_trap
603	  movl	%icc, PIL_14, %g4
604
6050:	retry
606
607	/*NOTREACHED*/
608	SET_SIZE(nonresumable_error)
609#endif /* lint */
610