xref: /titanic_52/usr/src/uts/i86pc/ml/interrupt.s (revision 7c478bd95313f5f23a4c958a745db2134aa03244)
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, Version 1.0 only
6 * (the "License").  You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22/*
23 * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
24 * Use is subject to license terms.
25 */
26
27/*	Copyright (c) 1990, 1991 UNIX System Laboratories, Inc.	*/
28/*	Copyright (c) 1984, 1986, 1987, 1988, 1989, 1990 AT&T	*/
29/*	  All Rights Reserved					*/
30
31/*	Copyright (c) 1987, 1988 Microsoft Corporation		*/
32/*	  All Rights Reserved					*/
33
34#pragma ident	"%Z%%M%	%I%	%E% SMI"
35
36#include <sys/asm_linkage.h>
37#include <sys/asm_misc.h>
38#include <sys/regset.h>
39#include <sys/psw.h>
40#include <sys/x86_archext.h>
41
42#if defined(__lint)
43
44#include <sys/types.h>
45#include <sys/thread.h>
46#include <sys/systm.h>
47
48#else   /* __lint */
49
50#include <sys/segments.h>
51#include <sys/pcb.h>
52#include <sys/trap.h>
53#include <sys/ftrace.h>
54#include <sys/traptrace.h>
55#include <sys/clock.h>
56#include <sys/panic.h>
57#include "assym.h"
58
59_ftrace_intr_thread_fmt:
60	.string	"intr_thread(): regs=0x%lx, int=0x%x, pil=0x%x"
61
62#endif	/* lint */
63
64#if defined(__i386)
65
66#if defined(__lint)
67
68void
69patch_tsc(void)
70{}
71
72#else	/* __lint */
73
74/*
75 * To cope with processors that do not implement the rdtsc instruction,
76 * we patch the kernel to use rdtsc if that feature is detected on the CPU.
77 * On an unpatched kernel, all locations requiring rdtsc are nop's.
78 *
79 * This function patches the nop's to rdtsc.
80 */
81	ENTRY_NP(patch_tsc)
82	movw	_rdtsc_insn, %cx
83	movw	%cx, _tsc_patch1
84	movw	%cx, _tsc_patch2
85	movw	%cx, _tsc_patch3
86	movw	%cx, _tsc_patch4
87	movw	%cx, _tsc_patch5
88	movw	%cx, _tsc_patch6
89	movw	%cx, _tsc_patch7
90	movw	%cx, _tsc_patch8
91	movw	%cx, _tsc_patch9
92	movw	%cx, _tsc_patch10
93	movw	%cx, _tsc_patch11
94	movw	%cx, _tsc_patch12
95	movw	%cx, _tsc_patch13
96	movw	%cx, _tsc_patch14
97	movw	%cx, _tsc_patch15
98	movw	%cx, _tsc_patch16
99	ret
100_rdtsc_insn:
101	rdtsc
102	SET_SIZE(patch_tsc)
103
104#endif	/* __lint */
105
106#endif	/* __i386 */
107
108
109#if defined(__lint)
110
111void
112_interrupt(void)
113{}
114
115#else	/* __lint */
116
117#if defined(__amd64)
118
119	/*
120	 * Common register usage:
121	 *
122	 * %rbx		cpu pointer
123	 * %r12		trap trace pointer -and- stash of
124	 *		vec across intr_thread dispatch.
125	 * %r13d	ipl of isr
126	 * %r14d	old ipl (ipl level we entered on)
127	 * %r15		interrupted thread stack pointer
128	 */
129	ENTRY_NP2(cmnint, _interrupt)
130
131	INTR_PUSH
132
133	/*
134	 * At the end of TRACE_PTR %r12 points to the current TRAPTRACE entry
135	 */
136	TRACE_PTR(%r12, %rax, %eax, %rdx, $TT_INTERRUPT)
137						/* Uses labels 8 and 9 */
138	TRACE_REGS(%r12, %rsp, %rax, %rbx)	/* Uses label 9 */
139	TRACE_STAMP(%r12)		/* Clobbers %eax, %edx, uses 9 */
140
141	DISABLE_INTR_FLAGS		/* (and set kernel flag values) */
142
143	movq	%rsp, %rbp
144
145	TRACE_STACK(%r12)
146
147	LOADCPU(%rbx)				/* &cpu */
148	leaq	REGOFF_TRAPNO(%rbp), %rsi	/* &vector */
149	movl	CPU_PRI(%rbx), %r14d		/* old ipl */
150	movl	CPU_SOFTINFO(%rbx), %edx
151
152#ifdef TRAPTRACE
153	movl	$255, TTR_IPL(%r12)
154	movl	%r14d, %edi
155	movb	%dil, TTR_PRI(%r12)
156	movl	CPU_BASE_SPL(%rbx), %edi
157	movb	%dil, TTR_SPL(%r12)
158	movb	$255, TTR_VECTOR(%r12)
159#endif
160
161	/*
162	 * Check to see if the trap number is T_SOFTINT; if it is,
163	 * jump straight to dosoftint now.
164	 */
165	cmpq	$T_SOFTINT, (%rsi)
166	je	dosoftint
167
168	/*
169	 * Raise the interrupt priority level, returns newpil.
170	 * (The vector address is in %rsi so setlvl can update it.)
171	 */
172	movl	%r14d, %edi			/* old ipl */
173						/* &vector */
174	call	*setlvl(%rip)
175
176#ifdef TRAPTRACE
177	movb	%al, TTR_IPL(%r12)
178#endif
179	/*
180	 * check for spurious interrupt
181	 */
182	cmpl	$-1, %eax
183	je	_sys_rtt
184
185#ifdef TRAPTRACE
186	movl	%r14d, %edx
187	movb	%dl, TTR_PRI(%r12)
188	movl	CPU_BASE_SPL(%rbx), %edx
189	movb	%dl, TTR_SPL(%r12)
190#endif
191	movl	%eax, CPU_PRI(%rbx)		/* update ipl */
192
193#ifdef TRAPTRACE
194	movl	REGOFF_TRAPNO(%rbp), %edx
195	movb	%dl, TTR_VECTOR(%r12)
196#endif
197	movl	%eax, %r13d			/* ipl of isr */
198
199	/*
200	 * At this point we can take one of two paths.
201	 * If the new level is at or below lock level, we will
202	 * run this interrupt in a separate thread.
203	 */
204	cmpl	$LOCK_LEVEL, %eax
205	jbe	intr_thread
206
207	movq	%rbx, %rdi		/* &cpu */
208	movl	%r13d, %esi		/* ipl */
209	movl	%r14d, %edx		/* old ipl */
210	movq	%rbp, %rcx		/* &regs */
211	call	hilevel_intr_prolog
212	orl	%eax, %eax		/* zero if need to switch stack */
213	jnz	1f
214
215	/*
216	 * Save the thread stack and get on the cpu's interrupt stack
217	 */
218	movq	%rsp, %r15
219	movq	CPU_INTR_STACK(%rbx), %rsp
2201:
221
222	sti
223
224	/*
225	 * Walk the list of handlers for this vector, calling
226	 * them as we go until no more interrupts are claimed.
227	 */
228	movl	REGOFF_TRAPNO(%rbp), %edi
229	call	av_dispatch_autovect
230
231	cli
232
233	movq	%rbx, %rdi			/* &cpu */
234	movl	%r13d, %esi			/* ipl */
235	movl	%r14d, %edx			/* oldipl */
236	movl	REGOFF_TRAPNO(%rbp), %ecx	/* vec */
237	call	hilevel_intr_epilog
238	orl	%eax, %eax		/* zero if need to switch stack */
239	jnz	2f
240	movq	%r15, %rsp
2412:	/*
242	 * Check for, and execute, softints before we iret.
243	 *
244	 * (dosoftint expects oldipl in %r14d (which is where it is)
245	 * the cpu pointer in %rbx (which is where it is) and the
246	 * softinfo in %edx (which is where we'll put it right now))
247	 */
248	movl	CPU_SOFTINFO(%rbx), %edx
249	orl	%edx, %edx
250	jz	_sys_rtt
251	jmp	dosoftint
252	/*NOTREACHED*/
253
254	SET_SIZE(cmnint)
255	SET_SIZE(_interrupt)
256
257/*
258 * Handle an interrupt in a new thread
259 *
260 * As we branch here, interrupts are still masked,
261 * %rbx still contains the cpu pointer,
262 * %r14d contains the old ipl that we came in on, and
263 * %eax contains the new ipl that we got from the setlvl routine
264 */
265
266	ENTRY_NP(intr_thread)
267
268	movq	%rbx, %rdi	/* &cpu */
269	movq	%rbp, %rsi	/* &regs = stack pointer for _sys_rtt */
270	movl	REGOFF_TRAPNO(%rbp), %r12d	/* stash the vec */
271	movl	%eax, %edx	/* new pil from setlvlx() */
272	call	intr_thread_prolog
273	movq	%rsp, %r15
274	movq	%rax, %rsp	/* t_stk from interrupt thread */
275	movq	%rsp, %rbp
276
277	sti
278
279	testl	$FTRACE_ENABLED, CPU_FTRACE_STATE(%rbx)
280	jz	1f
281	/*
282	 * ftracing support. do we need this on x86?
283	 */
284	leaq	_ftrace_intr_thread_fmt(%rip), %rdi
285	movq	%rbp, %rsi			/* &regs */
286	movl	%r12d, %edx			/* vec */
287	movq	CPU_THREAD(%rbx), %r11		/* (the interrupt thread) */
288	movzbl	T_PIL(%r11), %ecx		/* newipl */
289	call	ftrace_3_notick
2901:
291	movl	%r12d, %edi			/* vec */
292	call	av_dispatch_autovect
293
294	cli
295
296	movq	%rbx, %rdi			/* &cpu */
297	movl	%r12d, %esi			/* vec */
298	movl	%r14d, %edx			/* oldpil */
299	call	intr_thread_epilog
300	/*
301	 * If we return from here (we might not if the interrupted thread
302	 * has exited or blocked, in which case we'll have quietly swtch()ed
303	 * away) then we need to switch back to our old %rsp
304	 */
305	movq	%r15, %rsp
306	movq	%rsp, %rbp
307	/*
308	 * Check for, and execute, softints before we iret.
309	 *
310	 * (dosoftint expects oldpil in %r14d, the cpu pointer in %rbx and
311	 * the mcpu_softinfo.st_pending field in %edx.
312	 */
313	movl	CPU_SOFTINFO(%rbx), %edx
314	orl	%edx, %edx
315	jz	_sys_rtt
316	/*FALLTHROUGH*/
317
318/*
319 * Process soft interrupts.
320 * Interrupts are masked, and we have a minimal frame on the stack.
321 * %edx should contain the mcpu_softinfo.st_pending field
322 */
323
324	ALTENTRY(dosoftint)
325
326	movq	%rbx, %rdi	/* &cpu */
327	movq	%rbp, %rsi	/* &regs = stack pointer for _sys_rtt */
328				/* cpu->cpu_m.mcpu_softinfo.st_pending */
329	movl	%r14d, %ecx	/* oldipl */
330	call	dosoftint_prolog
331	/*
332	 * dosoftint_prolog() usually returns a stack pointer for the
333	 * interrupt thread that we must switch to.  However, if the
334	 * returned stack pointer is NULL, then the software interrupt was
335	 * too low in priority to run now; we'll catch it another time.
336	 */
337	orq	%rax, %rax
338	jz	_sys_rtt
339	movq	%rsp, %r15
340	movq	%rax, %rsp	/* t_stk from interrupt thread */
341	movq	%rsp, %rbp
342
343	sti
344
345	/*
346	 * Enabling interrupts (above) could raise the current ipl
347	 * and base spl.  But, we continue processing the current soft
348	 * interrupt and we will check the base spl next time around
349	 * so that blocked interrupt threads get a chance to run.
350	 */
351	movq	CPU_THREAD(%rbx), %r11	/* now an interrupt thread */
352	movzbl	T_PIL(%r11), %edi
353	call	av_dispatch_softvect
354
355	cli
356
357	movq	%rbx, %rdi		/* &cpu */
358	movl	%r14d, %esi		/* oldpil */
359	call	dosoftint_epilog
360	movq	%r15, %rsp		/* back on old stack pointer */
361	movq	%rsp, %rbp
362	movl	CPU_SOFTINFO(%rbx), %edx
363	orl	%edx, %edx
364	jz	_sys_rtt
365	jmp	dosoftint
366
367	SET_SIZE(dosoftint)
368	SET_SIZE(intr_thread)
369
370#elif defined(__i386)
371
372/*
373 * One day, this should just invoke the C routines that know how to
374 * do all the interrupt bookkeeping.  In the meantime, try
375 * and make the assembler a little more comprehensible.
376 */
377
378#define	INC64(basereg, offset)			\
379	addl	$1, offset(basereg);		\
380	adcl	$0, offset + 4(basereg)
381
382#define	TSC_CLR(basereg, offset)		\
383	movl	$0, offset(basereg);		\
384	movl	$0, offset + 4(basereg)
385
386/*
387 * The following macros assume the time value is in %edx:%eax
388 * e.g. from a rdtsc instruction.
389 */
390#define	TSC_MOV(reg, offset)		\
391	movl	%eax, offset(reg);	\
392	movl	%edx, offset + 4(reg)
393
394#define	TSC_ADD_TO(reg, offset)		\
395	addl	%eax, offset(reg);	\
396	adcl	%edx, offset + 4(reg)
397
398#define	TSC_SUB_FROM(reg, offset)	\
399	subl	offset(reg), %eax;	\
400	sbbl	offset + 4(reg), %edx	/* interval in edx:eax */
401
402/*
403 * basereg   - pointer to cpu struct
404 * pilreg    - pil or converted pil (pil - (LOCK_LEVEL + 1))
405 * pilreg_32 - 32-bit version of pilreg
406 *
407 * Returns (base + pil * 8) in pilreg
408 */
409#define	PILBASE(basereg, pilreg)	\
410	lea	(basereg, pilreg, 8), pilreg
411
412/*
413 * Returns (base + (pil - (LOCK_LEVEL + 1)) * 8) in pilreg
414 */
415#define	HIGHPILBASE(basereg, pilreg, pilreg_32)		\
416	subl	$LOCK_LEVEL + 1, pilreg_32;		\
417	PILBASE(basereg, pilreg)
418
419/*
420 * cpu_stats.sys.intr[PIL]++
421 */
422#define	INC_CPU_STATS_INTR(pilreg, tmpreg, tmpreg_32, basereg)	\
423	movl	pilreg, tmpreg_32;				\
424	PILBASE(basereg, tmpreg);				\
425	INC64(tmpreg, _CONST(CPU_STATS_SYS_INTR - 8))
426
427/*
428 * Unlink thread from CPU's list
429 */
430#define	UNLINK_INTR_THREAD(cpureg, ithread, tmpreg)	\
431	mov	CPU_INTR_THREAD(cpureg), ithread;	\
432	mov	T_LINK(ithread), tmpreg;		\
433	mov	tmpreg, CPU_INTR_THREAD(cpureg)
434
435/*
436 * Link a thread into CPU's list
437 */
438#define	LINK_INTR_THREAD(cpureg, ithread, tmpreg)	\
439	mov	CPU_INTR_THREAD(cpureg), tmpreg;	\
440	mov	tmpreg, T_LINK(ithread);		\
441	mov	ithread, CPU_INTR_THREAD(cpureg)
442
443#if defined(DEBUG)
444
445/*
446 * Do not call panic, if panic is already in progress.
447 */
448#define	__PANIC(msg, label)		\
449	cmpl	$0, panic_quiesce;		\
450	jne	label;				\
451	pushl	$msg;				\
452	call	panic
453
454#define	__CMP64_JNE(basereg, offset, label)	\
455	cmpl	$0, offset(basereg);		\
456	jne	label;				\
457	cmpl	$0, offset + 4(basereg);	\
458	jne	label
459
460/*
461 * ASSERT(!(CPU->cpu_intr_actv & (1 << PIL)))
462 */
463#define	ASSERT_NOT_CPU_INTR_ACTV(pilreg, basereg, msg)	\
464	btl	pilreg, CPU_INTR_ACTV(basereg);		\
465	jnc	4f;					\
466	__PANIC(msg, 4f);				\
4674:
468
469/*
470 * ASSERT(CPU->cpu_intr_actv & (1 << PIL))
471 */
472#define	ASSERT_CPU_INTR_ACTV(pilreg, basereg, msg)	\
473	btl	pilreg, CPU_INTR_ACTV(basereg);		\
474	jc	5f;					\
475	__PANIC(msg, 5f);				\
4765:
477
478/*
479 * ASSERT(CPU->cpu_pil_high_start != 0)
480 */
481#define	ASSERT_CPU_PIL_HIGH_START_NZ(basereg)			\
482	__CMP64_JNE(basereg, CPU_PIL_HIGH_START, 6f);		\
483	__PANIC(_interrupt_timestamp_zero, 6f);		\
4846:
485
486/*
487 * ASSERT(t->t_intr_start != 0)
488 */
489#define	ASSERT_T_INTR_START_NZ(basereg)				\
490	__CMP64_JNE(basereg, T_INTR_START, 7f);			\
491	__PANIC(_intr_thread_t_intr_start_zero, 7f);	\
4927:
493
494_interrupt_actv_bit_set:
495	.string	"_interrupt(): cpu_intr_actv bit already set for PIL"
496_interrupt_actv_bit_not_set:
497	.string	"_interrupt(): cpu_intr_actv bit not set for PIL"
498_interrupt_timestamp_zero:
499	.string "_interrupt(): timestamp zero upon handler return"
500_intr_thread_actv_bit_not_set:
501	.string	"intr_thread():	cpu_intr_actv bit not set for PIL"
502_intr_thread_t_intr_start_zero:
503	.string	"intr_thread():	t_intr_start zero upon handler return"
504_dosoftint_actv_bit_set:
505	.string	"dosoftint(): cpu_intr_actv bit already set for PIL"
506_dosoftint_actv_bit_not_set:
507	.string	"dosoftint(): cpu_intr_actv bit not set for PIL"
508
509	DGDEF(intr_thread_cnt)
510
511#else
512#define	ASSERT_NOT_CPU_INTR_ACTV(pilreg, basereg, msg)
513#define	ASSERT_CPU_INTR_ACTV(pilreg, basereg, msg)
514#define	ASSERT_CPU_PIL_HIGH_START_NZ(basereg)
515#define	ASSERT_T_INTR_START_NZ(basereg)
516#endif
517
518	ENTRY_NP2(cmnint, _interrupt)
519
520	INTR_PUSH
521
522	/*
523	 * At the end of TRACE_PTR %esi points to the current TRAPTRACE entry
524	 */
525	TRACE_PTR(%esi, %eax, %eax, %edx, $TT_INTERRUPT)
526						/* Uses labels 8 and 9 */
527	TRACE_REGS(%esi, %esp, %eax, %ebx)	/* Uses label 9 */
528	TRACE_STAMP(%esi)		/* Clobbers %eax, %edx, uses 9 */
529
530	movl	%esp, %ebp
531	DISABLE_INTR_FLAGS
532	LOADCPU(%ebx)		/* get pointer to CPU struct. Avoid gs refs */
533	leal    REGOFF_TRAPNO(%ebp), %ecx	/* get address of vector */
534	movl	CPU_PRI(%ebx), %edi		/* get ipl */
535	movl	CPU_SOFTINFO(%ebx), %edx
536
537	/
538	/ Check to see if the trap number is T_SOFTINT; if it is, we'll
539	/ jump straight to dosoftint now.
540	/
541	cmpl	$T_SOFTINT, (%ecx)
542	je	dosoftint
543
544	/ raise interrupt priority level
545	/ oldipl is in %edi, vectorp is in %ecx
546	/ newipl is returned in %eax
547	pushl	%ecx
548	pushl	%edi
549	call    *setlvl
550	popl	%edi			/* save oldpil in %edi */
551	popl	%ecx
552
553#ifdef TRAPTRACE
554	movb	%al, TTR_IPL(%esi)
555#endif
556
557	/ check for spurious interrupt
558	cmp	$-1, %eax
559	je	_sys_rtt
560
561#ifdef TRAPTRACE
562	movl	CPU_PRI(%ebx), %edx
563	movb	%dl, TTR_PRI(%esi)
564	movl	CPU_BASE_SPL(%ebx), %edx
565	movb	%dl, TTR_SPL(%esi)
566#endif
567
568	movl	%eax, CPU_PRI(%ebx) /* update ipl */
569	movl	REGOFF_TRAPNO(%ebp), %ecx /* reload the interrupt vector */
570
571#ifdef TRAPTRACE
572	movb	%cl, TTR_VECTOR(%esi)
573#endif
574
575	/ At this point we can take one of two paths.  If the new priority
576	/ level is less than or equal to LOCK LEVEL then we jump to code that
577	/ will run this interrupt as a separate thread.  Otherwise the
578	/ interrupt is NOT run as a separate thread.
579
580	/ %edi - old priority level
581	/ %ebp - pointer to REGS
582	/ %ecx - translated vector
583	/ %eax - ipl of isr
584	/ %ebx - cpu pointer
585
586	cmpl 	$LOCK_LEVEL, %eax	/* compare to highest thread level */
587	jbe	intr_thread		/* process as a separate thread */
588
589	cmpl	$CBE_HIGH_PIL, %eax	/* Is this a CY_HIGH_LEVEL interrupt? */
590	jne	2f
591
592	movl	REGOFF_PC(%ebp), %esi
593	movl	%edi, CPU_PROFILE_PIL(%ebx)	/* record interrupted PIL */
594	testw	$CPL_MASK, REGOFF_CS(%ebp)	/* trap from supervisor mode? */
595	jz	1f
596	movl	%esi, CPU_PROFILE_UPC(%ebx)	/* record user PC */
597	movl	$0, CPU_PROFILE_PC(%ebx)	/* zero kernel PC */
598	jmp	2f
599
6001:
601	movl	%esi, CPU_PROFILE_PC(%ebx)	/* record kernel PC */
602	movl	$0, CPU_PROFILE_UPC(%ebx)	/* zero user PC */
603
6042:
605	pushl	%ecx				/* vec */
606	pushl	%eax				/* newpil */
607
608	/
609	/ See if we are interrupting another high-level interrupt.
610	/
611	movl	CPU_INTR_ACTV(%ebx), %eax
612	andl	$CPU_INTR_ACTV_HIGH_LEVEL_MASK, %eax
613	jz	0f
614	/
615	/ We have interrupted another high-level interrupt.
616	/ Load starting timestamp, compute interval, update cumulative counter.
617	/
618	bsrl	%eax, %ecx		/* find PIL of interrupted handler */
619	HIGHPILBASE(%ebx, %ecx, %ecx)
620_tsc_patch1:
621	nop; nop			/* patched to rdtsc if available */
622	TSC_SUB_FROM(%ecx, CPU_PIL_HIGH_START)
623	addl	$CPU_INTRSTAT_LOW_PIL_OFFSET, %ecx	/* offset PILs 0-10 */
624	TSC_ADD_TO(%ecx, CPU_INTRSTAT)
625	/
626	/ Another high-level interrupt is active below this one, so
627	/ there is no need to check for an interrupt thread. That will be
628	/ done by the lowest priority high-level interrupt active.
629	/
630	jmp	1f
6310:
632	/
633	/ See if we are interrupting a low-level interrupt thread.
634	/
635	movl	CPU_THREAD(%ebx), %esi
636	testw	$T_INTR_THREAD, T_FLAGS(%esi)
637	jz	1f
638	/
639	/ We have interrupted an interrupt thread. Account for its time slice
640	/ only if its time stamp is non-zero.
641	/
642	cmpl	$0, T_INTR_START+4(%esi)
643	jne	0f
644	cmpl	$0, T_INTR_START(%esi)
645	je	1f
6460:
647	movzbl	T_PIL(%esi), %ecx /* %ecx has PIL of interrupted handler */
648	PILBASE(%ebx, %ecx)
649_tsc_patch2:
650	nop; nop			/* patched to rdtsc if available */
651	TSC_SUB_FROM(%esi, T_INTR_START)
652	TSC_CLR(%esi, T_INTR_START)
653	TSC_ADD_TO(%ecx, CPU_INTRSTAT)
6541:
655	/ Store starting timestamp in CPU structure for this PIL.
656	popl	%ecx			/* restore new PIL */
657	pushl	%ecx
658	HIGHPILBASE(%ebx, %ecx, %ecx)
659_tsc_patch3:
660	nop; nop			/* patched to rdtsc if available */
661	TSC_MOV(%ecx, CPU_PIL_HIGH_START)
662
663	popl	%eax			/* restore new pil */
664	popl	%ecx			/* vec */
665	/
666	/ Set bit for this PIL in CPU's interrupt active bitmask.
667	/
668
669	ASSERT_NOT_CPU_INTR_ACTV(%eax, %ebx, _interrupt_actv_bit_set)
670
671	/ Save old CPU_INTR_ACTV
672	movl	CPU_INTR_ACTV(%ebx), %esi
673
674	cmpl	$15, %eax
675	jne	0f
676	/ PIL-15 interrupt. Increment nest-count in upper 16 bits of intr_actv
677	incw	CPU_INTR_ACTV_REF(%ebx)	/* increment ref count */
6780:
679	btsl	%eax, CPU_INTR_ACTV(%ebx)
680	/
681	/ Handle high-level nested interrupt on separate interrupt stack
682	/
683	testl	$CPU_INTR_ACTV_HIGH_LEVEL_MASK, %esi
684	jnz	onstack			/* already on interrupt stack */
685	movl	%esp, %eax
686	movl	CPU_INTR_STACK(%ebx), %esp	/* get on interrupt stack */
687	pushl	%eax			/* save the thread stack pointer */
688onstack:
689	movl	$autovect, %esi		/* get autovect structure before */
690					/* sti to save on AGI later */
691	sti				/* enable interrupts */
692	pushl	%ecx			/* save interrupt vector */
693	/
694	/ Get handler address
695	/
696pre_loop1:
697	movl	AVH_LINK(%esi, %ecx, 8), %esi
698	xorl	%ebx, %ebx	/* bh is no. of intpts in chain */
699				/* bl is DDI_INTR_CLAIMED status of chain */
700	testl	%esi, %esi		/* if pointer is null */
701	jz	.intr_ret		/* then skip */
702loop1:
703	incb	%bh
704	movl	AV_VECTOR(%esi), %edx	/* get the interrupt routine */
705	testl	%edx, %edx		/* if func is null */
706	jz	.intr_ret		/* then skip */
707	pushl	$0
708	pushl	AV_INTARG2(%esi)
709	pushl	AV_INTARG1(%esi)
710	pushl	AV_VECTOR(%esi)
711	pushl	AV_DIP(%esi)
712	call	__dtrace_probe_interrupt__start
713	pushl	AV_INTARG2(%esi)	/* get 2nd arg to interrupt routine */
714	pushl	AV_INTARG1(%esi)	/* get first arg to interrupt routine */
715	call	*%edx			/* call interrupt routine with arg */
716	addl	$8, %esp
717	movl	%eax, 16(%esp)
718	call	__dtrace_probe_interrupt__complete
719	addl	$20, %esp
720	orb	%al, %bl		/* see if anyone claims intpt. */
721	movl	AV_LINK(%esi), %esi	/* get next routine on list */
722	testl	%esi, %esi		/* if pointer is non-null */
723	jnz	loop1			/* then continue */
724
725.intr_ret:
726	cmpb	$1, %bh		/* if only 1 intpt in chain, it is OK */
727	je	.intr_ret1
728	orb	%bl, %bl	/* If no one claims intpt, then it is OK */
729	jz	.intr_ret1
730	movl	(%esp), %ecx		/* else restore intr vector */
731	movl	$autovect, %esi		/* get autovect structure */
732	jmp	pre_loop1		/* and try again. */
733
734.intr_ret1:
735	LOADCPU(%ebx)			/* get pointer to cpu struct */
736
737	cli
738	movl	CPU_PRI(%ebx), %esi
739
740	/ cpu_stats.sys.intr[PIL]++
741	INC_CPU_STATS_INTR(%esi, %eax, %eax, %ebx)
742
743	/
744	/ Clear bit for this PIL in CPU's interrupt active bitmask.
745	/
746
747	ASSERT_CPU_INTR_ACTV(%esi, %ebx, _interrupt_actv_bit_not_set)
748
749	cmpl	$15, %esi
750	jne	0f
751	/ Only clear bit if reference count is now zero.
752	decw	CPU_INTR_ACTV_REF(%ebx)
753	jnz	1f
7540:
755	btrl	%esi, CPU_INTR_ACTV(%ebx)
7561:
757	/
758	/ Take timestamp, compute interval, update cumulative counter.
759	/ esi = PIL
760_tsc_patch4:
761	nop; nop			/* patched to rdtsc if available */
762	HIGHPILBASE(%ebx, %esi, %esi)
763
764	ASSERT_CPU_PIL_HIGH_START_NZ(%esi)
765
766	TSC_SUB_FROM(%esi, CPU_PIL_HIGH_START)
767	addl	$CPU_INTRSTAT_LOW_PIL_OFFSET, %esi	/* offset PILs 0-10 */
768	TSC_ADD_TO(%esi, CPU_INTRSTAT)
769	/
770	/ Check for lower-PIL nested high-level interrupt beneath current one
771	/ If so, place a starting timestamp in its pil_high_start entry.
772	/
773	movl	CPU_INTR_ACTV(%ebx), %eax
774	movl	%eax, %esi
775	andl	$CPU_INTR_ACTV_HIGH_LEVEL_MASK, %eax
776	jz	0f
777	bsrl	%eax, %ecx		/* find PIL of nested interrupt */
778	HIGHPILBASE(%ebx, %ecx, %ecx)
779_tsc_patch5:
780	nop; nop			/* patched to rdtsc if available */
781	TSC_MOV(%ecx, CPU_PIL_HIGH_START)
782	/
783	/ Another high-level interrupt is active below this one, so
784	/ there is no need to check for an interrupt thread. That will be
785	/ done by the lowest priority high-level interrupt active.
786	/
787	jmp	1f
7880:
789	/ Check to see if there is a low-level interrupt active. If so,
790	/ place a starting timestamp in the thread structure.
791	movl	CPU_THREAD(%ebx), %esi
792	testw	$T_INTR_THREAD, T_FLAGS(%esi)
793	jz	1f
794_tsc_patch6:
795	nop; nop			/* patched to rdtsc if available */
796	TSC_MOV(%esi, T_INTR_START)
7971:
798	movl	%edi, CPU_PRI(%ebx)
799				/* interrupt vector already on stack */
800	pushl	%edi			/* old ipl */
801	call	*setlvlx
802	addl	$8, %esp		/* eax contains the current ipl */
803
804	movl	CPU_INTR_ACTV(%ebx), %esi /* reset stack pointer if no more */
805	shrl	$LOCK_LEVEL + 1, %esi	/* HI PRI intrs. */
806	jnz	.intr_ret2
807	popl	%esp			/* restore the thread stack pointer */
808.intr_ret2:
809	movl	CPU_SOFTINFO(%ebx), %edx /* any pending software interrupts */
810	orl	%edx, %edx
811	jz	_sys_rtt
812	jmp	dosoftint	/* check for softints before we return. */
813	SET_SIZE(cmnint)
814	SET_SIZE(_interrupt)
815
816#endif	/* __i386 */
817
818/*
819 * Declare a uintptr_t which has the size of _interrupt to enable stack
820 * traceback code to know when a regs structure is on the stack.
821 */
822	.globl	_interrupt_size
823	.align	CLONGSIZE
824_interrupt_size:
825	.NWORD	. - _interrupt
826	.type	_interrupt_size, @object
827
828#endif	/* __lint */
829
830#if defined(__i386)
831
832/*
833 * Handle an interrupt in a new thread.
834 *	Entry:  traps disabled.
835 *		%edi - old priority level
836 *		%ebp - pointer to REGS
837 *		%ecx - translated vector
838 *		%eax - ipl of isr.
839 *		%ebx - pointer to CPU struct
840 *	Uses:
841 */
842
843#if !defined(__lint)
844
845	ENTRY_NP(intr_thread)
846	/
847	/ Set bit for this PIL in CPU's interrupt active bitmask.
848	/
849
850	ASSERT_NOT_CPU_INTR_ACTV(%eax, %ebx, _interrupt_actv_bit_set)
851
852	btsl	%eax, CPU_INTR_ACTV(%ebx)
853
854	/ Get set to run interrupt thread.
855	/ There should always be an interrupt thread since we allocate one
856	/ for each level on the CPU.
857	/
858	/ Note that the code in kcpc_overflow_intr -relies- on the ordering
859	/ of events here - in particular that t->t_lwp of the interrupt
860	/ thread is set to the pinned thread *before* curthread is changed
861	/
862	movl	CPU_THREAD(%ebx), %edx		/* cur thread in edx */
863
864	/
865	/ Are we interrupting an interrupt thread? If so, account for it.
866	/
867	testw	$T_INTR_THREAD, T_FLAGS(%edx)
868	jz	0f
869	pushl	%ecx
870	pushl	%eax
871	movl	%edx, %esi
872_tsc_patch7:
873	nop; nop			/* patched to rdtsc if available */
874	TSC_SUB_FROM(%esi, T_INTR_START)
875	TSC_CLR(%esi, T_INTR_START)
876	movzbl	T_PIL(%esi), %ecx
877	PILBASE(%ebx, %ecx)
878	TSC_ADD_TO(%ecx, CPU_INTRSTAT)
879	movl	%esi, %edx
880	popl	%eax
881	popl	%ecx
8820:
883	movl	%esp, T_SP(%edx)	/* mark stack in curthread for resume */
884	pushl	%edi			/* get a temporary register */
885	UNLINK_INTR_THREAD(%ebx, %esi, %edi)
886
887	movl	T_LWP(%edx), %edi
888	movl	%edx, T_INTR(%esi)		/* push old thread */
889	movl	%edi, T_LWP(%esi)
890	/
891	/ Threads on the interrupt thread free list could have state already
892	/ set to TS_ONPROC, but it helps in debugging if they're TS_FREE
893	/
894	movl	$ONPROC_THREAD, T_STATE(%esi)
895	/
896	/ chain the interrupted thread onto list from the interrupt thread.
897	/ Set the new interrupt thread as the current one.
898	/
899	popl	%edi			/* Don't need a temp reg anymore */
900	movl	T_STACK(%esi), %esp		/* interrupt stack pointer */
901	movl	%esp, %ebp
902	movl	%esi, CPU_THREAD(%ebx)		/* set new thread */
903	pushl	%eax				/* save the ipl */
904	/
905	/ Initialize thread priority level from intr_pri
906	/
907	movb	%al, T_PIL(%esi)	/* store pil */
908	movzwl	intr_pri, %ebx		/* XXX Can cause probs if new class */
909					/* is loaded on some other cpu. */
910	addl	%ebx, %eax		/* convert level to dispatch priority */
911	movw	%ax, T_PRI(%esi)
912
913	/
914	/ Take timestamp and store it in the thread structure.
915	/
916	movl	%eax, %ebx		/* save priority over rdtsc */
917_tsc_patch8:
918	nop; nop			/* patched to rdtsc if available */
919	TSC_MOV(%esi, T_INTR_START)
920	movl	%ebx, %eax		/* restore priority */
921
922	/ The following 3 instructions need not be in cli.
923	/ Putting them here only to avoid the AGI penalty on Pentiums.
924
925	pushl	%ecx			/* save interrupt vector. */
926	pushl	%esi			/* save interrupt thread */
927	movl	$autovect, %esi		/* get autovect structure */
928	sti				/* enable interrupts */
929
930	/ Fast event tracing.
931	LOADCPU(%ebx)
932	movl	CPU_FTRACE_STATE(%ebx), %ebx
933	testl	$FTRACE_ENABLED, %ebx
934	jz	1f
935
936	movl	8(%esp), %ebx
937	pushl	%ebx			/* ipl */
938	pushl	%ecx			/* int vector */
939	movl	T_SP(%edx), %ebx
940	pushl	%ebx			/* &regs */
941	pushl	$_ftrace_intr_thread_fmt
942	call	ftrace_3_notick
943	addl	$8, %esp
944	popl	%ecx			/* restore int vector */
945	addl	$4, %esp
9461:
947pre_loop2:
948	movl	AVH_LINK(%esi, %ecx, 8), %esi
949	xorl	%ebx, %ebx	/* bh is cno. of intpts in chain */
950				/* bl is DDI_INTR_CLAIMED status of * chain */
951	testl	%esi, %esi	/* if pointer is null */
952	jz	loop_done2	/* we're done */
953loop2:
954	movl	AV_VECTOR(%esi), %edx	/* get the interrupt routine */
955	testl	%edx, %edx		/* if pointer is null */
956	jz	loop_done2		/* we're done */
957	incb	%bh
958	pushl	$0
959	pushl	AV_INTARG2(%esi)
960	pushl	AV_INTARG1(%esi)
961	pushl	AV_VECTOR(%esi)
962	pushl	AV_DIP(%esi)
963	call	__dtrace_probe_interrupt__start
964	pushl	AV_INTARG2(%esi)	/* get 2nd arg to interrupt routine */
965	pushl	AV_INTARG1(%esi)	/* get first arg to interrupt routine */
966	call	*%edx			/* call interrupt routine with arg */
967	addl	$8, %esp
968	movl	%eax, 16(%esp)
969	call	__dtrace_probe_interrupt__complete
970	addl	$20, %esp
971	orb	%al, %bl		/* see if anyone claims intpt. */
972	movl	AV_LINK(%esi), %esi	/* get next routine on list */
973	testl	%esi, %esi		/* if pointer is non-null */
974	jnz	loop2			/* continue */
975loop_done2:
976	cmpb	$1, %bh		/* if only 1 intpt in chain, it is OK */
977	je	.loop_done2_1
978	orb	%bl, %bl	/* If no one claims intpt, then it is OK */
979	jz	.loop_done2_1
980	movl	$autovect, %esi		/* else get autovect structure */
981	movl	4(%esp), %ecx		/* restore intr vector */
982	jmp	pre_loop2		/* and try again. */
983.loop_done2_1:
984	popl	%esi			/* restore intr thread pointer */
985
986	LOADCPU(%ebx)
987
988	cli		/* protect interrupt thread pool and intr_actv */
989	movzbl	T_PIL(%esi), %eax
990
991	/ Save value in regs
992	pushl	%eax			/* current pil */
993	pushl	%edx			/* (huh?) */
994	pushl	%edi			/* old pil */
995
996	/ cpu_stats.sys.intr[PIL]++
997	INC_CPU_STATS_INTR(%eax, %edx, %edx, %ebx)
998
999	/
1000	/ Take timestamp, compute interval, and update cumulative counter.
1001	/ esi = thread pointer, ebx = cpu pointer, eax = PIL
1002	/
1003	movl	%eax, %edi
1004
1005	ASSERT_T_INTR_START_NZ(%esi)
1006
1007_tsc_patch9:
1008	nop; nop			/* patched to rdtsc if available */
1009	TSC_SUB_FROM(%esi, T_INTR_START)
1010	PILBASE(%ebx, %edi)
1011	TSC_ADD_TO(%edi, CPU_INTRSTAT)
1012	popl	%edi
1013	popl	%edx
1014	popl	%eax
1015
1016	/
1017	/ Clear bit for this PIL in CPU's interrupt active bitmask.
1018	/
1019
1020	ASSERT_CPU_INTR_ACTV(%eax, %ebx, _intr_thread_actv_bit_not_set)
1021
1022	btrl	%eax, CPU_INTR_ACTV(%ebx)
1023
1024	/ if there is still an interrupted thread underneath this one
1025	/ then the interrupt was never blocked and the return is fairly
1026	/ simple.  Otherwise jump to intr_thread_exit
1027	cmpl	$0, T_INTR(%esi)
1028	je	intr_thread_exit
1029
1030	/
1031	/ link the thread back onto the interrupt thread pool
1032	LINK_INTR_THREAD(%ebx, %esi, %edx)
1033
1034	movl	CPU_BASE_SPL(%ebx), %eax	/* used below. */
1035	/ set the thread state to free so kmdb doesn't see it
1036	movl	$FREE_THREAD, T_STATE(%esi)
1037
1038	cmpl	%eax, %edi		/* if (oldipl >= basespl) */
1039	jae	intr_restore_ipl	/* then use oldipl */
1040	movl	%eax, %edi		/* else use basespl */
1041intr_restore_ipl:
1042	movl	%edi, CPU_PRI(%ebx)
1043					/* intr vector already on stack */
1044	pushl	%edi			/* old ipl */
1045	call	*setlvlx		/* eax contains the current ipl */
1046	/
1047	/ Switch back to the interrupted thread
1048	movl	T_INTR(%esi), %ecx
1049
1050	/ Place starting timestamp in interrupted thread's thread structure.
1051_tsc_patch10:
1052	nop; nop			/* patched to rdtsc if available */
1053	TSC_MOV(%ecx, T_INTR_START)
1054
1055	movl	T_SP(%ecx), %esp	/* restore stack pointer */
1056	movl	%esp, %ebp
1057	movl	%ecx, CPU_THREAD(%ebx)
1058
1059	movl	CPU_SOFTINFO(%ebx), %edx /* any pending software interrupts */
1060	orl	%edx, %edx
1061	jz	_sys_rtt
1062	jmp	dosoftint	/* check for softints before we return. */
1063
1064	/
1065	/ An interrupt returned on what was once (and still might be)
1066	/ an interrupt thread stack, but the interrupted process is no longer
1067	/ there.  This means the interrupt must have blocked.
1068	/
1069	/ There is no longer a thread under this one, so put this thread back
1070	/ on the CPU's free list and resume the idle thread which will dispatch
1071	/ the next thread to run.
1072	/
1073	/ All interrupts are disabled here
1074	/
1075
1076intr_thread_exit:
1077#ifdef DEBUG
1078	incl	intr_thread_cnt
1079#endif
1080	INC64(%ebx, CPU_STATS_SYS_INTRBLK)	/* cpu_stats.sys.intrblk++ */
1081	/
1082	/ Put thread back on the interrupt thread list.
1083	/ As a reminder, the regs at this point are
1084	/	esi	interrupt thread
1085	/	edi	old ipl
1086	/	ebx	ptr to CPU struct
1087
1088	/ Set CPU's base SPL level based on active interrupts bitmask
1089	call	set_base_spl
1090
1091	movl	CPU_BASE_SPL(%ebx), %edi
1092	movl	%edi, CPU_PRI(%ebx)
1093					/* interrupt vector already on stack */
1094	pushl	%edi
1095	call	*setlvlx
1096	addl	$8, %esp		/* XXX - don't need to pop since */
1097					/* we are ready to switch */
1098	call	splhigh			/* block all intrs below lock level */
1099	/
1100	/ Set the thread state to free so kmdb doesn't see it
1101	/
1102	movl	$FREE_THREAD, T_STATE(%esi)
1103	/
1104	/ Put thread on either the interrupt pool or the free pool and
1105	/ call swtch() to resume another thread.
1106	/
1107	LINK_INTR_THREAD(%ebx, %esi, %edx)
1108	call 	swtch
1109	/ swtch() shouldn't return
1110
1111	SET_SIZE(intr_thread)
1112
1113#endif	/* __lint */
1114#endif	/* __i386 */
1115
1116/*
1117 * Set Cpu's base SPL level, base on which interrupt levels are active
1118 *	Called at spl7 or above.
1119 */
1120
1121#if defined(__lint)
1122
1123void
1124set_base_spl(void)
1125{}
1126
1127#else	/* __lint */
1128
1129	ENTRY_NP(set_base_spl)
1130	movl	%gs:CPU_INTR_ACTV, %eax	/* load active interrupts mask */
1131	testl	%eax, %eax		/* is it zero? */
1132	jz	setbase
1133	testl	$0xff00, %eax
1134	jnz	ah_set
1135	shl	$24, %eax		/* shift 'em over so we can find */
1136					/* the 1st bit faster */
1137	bsrl	%eax, %eax
1138	subl	$24, %eax
1139setbase:
1140	movl	%eax, %gs:CPU_BASE_SPL	/* store base priority */
1141	ret
1142ah_set:
1143	shl	$16, %eax
1144	bsrl	%eax, %eax
1145	subl	$16, %eax
1146	jmp	setbase
1147	SET_SIZE(set_base_spl)
1148
1149#endif	/* __lint */
1150
1151#if defined(__i386)
1152
1153/*
1154 * int
1155 * intr_passivate(from, to)
1156 *      thread_id_t     from;           interrupt thread
1157 *      thread_id_t     to;             interrupted thread
1158 *
1159 *	intr_passivate(t, itp) makes the interrupted thread "t" runnable.
1160 *
1161 *	Since t->t_sp has already been saved, t->t_pc is all that needs
1162 *	set in this function.
1163 *
1164 *	Returns interrupt level of the thread.
1165 */
1166
1167#if defined(__lint)
1168
1169/* ARGSUSED */
1170int
1171intr_passivate(kthread_id_t from, kthread_id_t to)
1172{ return (0); }
1173
1174#else	/* __lint */
1175
1176	ENTRY(intr_passivate)
1177	movl	8(%esp), %eax		/* interrupted thread  */
1178	movl	$_sys_rtt, T_PC(%eax)	/* set T_PC for interrupted thread */
1179
1180	movl	4(%esp), %eax		/* interrupt thread */
1181	movl	T_STACK(%eax), %eax	/* get the pointer to the start of */
1182					/* of the interrupt thread stack */
1183	movl	-4(%eax), %eax		/* interrupt level was the first */
1184					/* thing pushed onto the stack */
1185	ret
1186	SET_SIZE(intr_passivate)
1187
1188#endif	/* __lint */
1189#endif	/* __i386 */
1190
1191#if defined(__lint)
1192
1193void
1194fakesoftint(void)
1195{}
1196
1197#else	/* __lint */
1198
1199	/
1200	/ If we're here, we're being called from splx() to fake a soft
1201	/ interrupt (note that interrupts are still disabled from splx()).
1202	/ We execute this code when a soft interrupt is posted at
1203	/ level higher than the CPU's current spl; when spl is lowered in
1204	/ splx(), it will see the softint and jump here.  We'll do exactly
1205	/ what a trap would do:  push our flags, %cs, %eip, error code
1206	/ and trap number (T_SOFTINT).  The cmnint() code will see T_SOFTINT
1207	/ and branch to the dosoftint() code.
1208	/
1209#if defined(__amd64)
1210
1211	/*
1212	 * In 64-bit mode, iretq -always- pops all five regs
1213	 * Imitate the 16-byte auto-align of the stack, and the
1214	 * zero-ed out %ss value.
1215	 */
1216	ENTRY_NP(fakesoftint)
1217	movq	%rsp, %r11
1218	andq	$-16, %rsp
1219	pushq	$KDS_SEL	/* %ss */
1220	pushq	%r11		/* %rsp */
1221	pushf			/* rflags */
1222	pushq	$KCS_SEL	/* %cs */
1223	leaq	fakesoftint_return(%rip), %r11
1224	pushq	%r11		/* %rip */
1225	pushq	$0		/* err */
1226	pushq	$T_SOFTINT	/* trap */
1227	jmp	cmnint
1228	SET_SIZE(fakesoftint)
1229
1230#elif defined(__i386)
1231
1232	ENTRY_NP(fakesoftint)
1233	pushf
1234	push	%cs
1235	push	$fakesoftint_return
1236	push	$0
1237	push	$T_SOFTINT
1238	jmp	cmnint
1239	SET_SIZE(fakesoftint)
1240
1241#endif	/* __i386 */
1242
1243	.align	CPTRSIZE
1244	.globl	_fakesoftint_size
1245	.type	_fakesoftint_size, @object
1246_fakesoftint_size:
1247	.NWORD	. - fakesoftint
1248	SET_SIZE(_fakesoftint_size)
1249
1250/*
1251 * dosoftint(old_pil in %edi, softinfo in %edx, CPU pointer in %ebx)
1252 * Process software interrupts
1253 * Interrupts are disabled here.
1254 */
1255#if defined(__i386)
1256
1257	ENTRY_NP(dosoftint)
1258
1259	bsrl	%edx, %edx		/* find highest pending interrupt */
1260	cmpl 	%edx, %edi		/* if curipl >= pri soft pending intr */
1261	jae	_sys_rtt		/* skip */
1262
1263	movl	%gs:CPU_BASE_SPL, %eax	/* check for blocked intr threads */
1264	cmpl	%edx, %eax		/* if basespl >= pri soft pending */
1265	jae	_sys_rtt		/* skip */
1266
1267	lock				/* MP protect */
1268	btrl	%edx, CPU_SOFTINFO(%ebx) /* clear the selected interrupt bit */
1269	jnc	dosoftint_again
1270
1271	movl	%edx, CPU_PRI(%ebx) /* set IPL to sofint level */
1272	pushl	%edx
1273	call	*setspl			/* mask levels upto the softint level */
1274	popl	%eax			/* priority we are at in %eax */
1275
1276	/ Get set to run interrupt thread.
1277	/ There should always be an interrupt thread since we allocate one
1278	/ for each level on the CPU.
1279	UNLINK_INTR_THREAD(%ebx, %esi, %edx)
1280
1281	/
1282	/ Note that the code in kcpc_overflow_intr -relies- on the ordering
1283	/ of events here - in particular that t->t_lwp of the interrupt
1284	/ thread is set to the pinned thread *before* curthread is changed
1285	/
1286	movl	CPU_THREAD(%ebx), %ecx
1287
1288	/ If we are interrupting an interrupt thread, account for it.
1289	testw	$T_INTR_THREAD, T_FLAGS(%ecx)
1290	jz	0f
1291	pushl	%eax
1292	movl	%eax, %ebp
1293_tsc_patch11:
1294	nop; nop			/* patched to rdtsc if available */
1295	PILBASE(%ebx, %ebp)
1296	TSC_SUB_FROM(%ecx, T_INTR_START)
1297	TSC_ADD_TO(%ebp, CPU_INTRSTAT)
1298	popl	%eax
12990:
1300	movl	T_LWP(%ecx), %ebp
1301	movl	%ebp, T_LWP(%esi)
1302	/
1303	/ Threads on the interrupt thread free list could have state already
1304	/ set to TS_ONPROC, but it helps in debugging if they're TS_FREE
1305	/ Could eliminate the next two instructions with a little work.
1306	/
1307	movl	$ONPROC_THREAD, T_STATE(%esi)
1308	/
1309	/ Push interrupted thread onto list from new thread.
1310	/ Set the new thread as the current one.
1311	/ Set interrupted thread's T_SP because if it is the idle thread,
1312	/ Resume() may use that stack between threads.
1313	/
1314	movl	%esp, T_SP(%ecx)		/* mark stack for resume */
1315	movl	%ecx, T_INTR(%esi)		/* push old thread */
1316	movl	%esi, CPU_THREAD(%ebx)		/* set new thread */
1317	movl	T_STACK(%esi), %esp		/* interrupt stack pointer */
1318	movl	%esp, %ebp
1319
1320	pushl	%eax			/* push ipl as first element in stack */
1321					/* see intr_passivate() */
1322	/
1323	/ Set bit for this PIL in CPU's interrupt active bitmask.
1324	/
1325
1326	ASSERT_NOT_CPU_INTR_ACTV(%eax, %ebx, _dosoftint_actv_bit_set)
1327
1328	btsl	%eax, CPU_INTR_ACTV(%ebx)
1329
1330	/
1331	/ Initialize thread priority level from intr_pri
1332	/
1333	movb	%al, T_PIL(%esi)	/* store pil */
1334	movzwl	intr_pri, %ecx
1335	addl	%eax, %ecx		/* convert level to dispatch priority */
1336	movw	%cx, T_PRI(%esi)
1337
1338	/
1339	/ Store starting timestamp in thread structure.
1340	/ esi = thread, ebx = cpu pointer, eax = PIL
1341	/
1342	movl	%eax, %ecx		/* save PIL from rdtsc clobber */
1343_tsc_patch12:
1344	nop; nop			/* patched to rdtsc if available */
1345	TSC_MOV(%esi, T_INTR_START)
1346
1347	sti				/* enable interrupts */
1348
1349	/
1350	/ Enabling interrupts (above) could raise the current
1351	/ IPL and base SPL. But, we continue processing the current soft
1352	/ interrupt and we will check the base SPL next time in the loop
1353	/ so that blocked interrupt thread would get a chance to run.
1354	/
1355
1356	/
1357	/ dispatch soft interrupts
1358	/
1359	pushl	%ecx
1360	call	av_dispatch_softvect
1361	addl	$4, %esp
1362
1363	cli				/* protect interrupt thread pool */
1364					/* and softinfo & sysinfo */
1365	movl	CPU_THREAD(%ebx), %esi	/* restore thread pointer */
1366	movzbl	T_PIL(%esi), %ecx
1367
1368	/ cpu_stats.sys.intr[PIL]++
1369	INC_CPU_STATS_INTR(%ecx, %edx, %edx, %ebx)
1370
1371	/
1372	/ Clear bit for this PIL in CPU's interrupt active bitmask.
1373	/
1374
1375	ASSERT_CPU_INTR_ACTV(%ecx, %ebx, _dosoftint_actv_bit_not_set)
1376
1377	btrl	%ecx, CPU_INTR_ACTV(%ebx)
1378
1379	/
1380	/ Take timestamp, compute interval, update cumulative counter.
1381	/ esi = thread, ebx = cpu, ecx = PIL
1382	/
1383	PILBASE(%ebx, %ecx)
1384_tsc_patch13:
1385	nop; nop		/* patched to rdtsc if available */
1386	TSC_SUB_FROM(%esi, T_INTR_START)
1387	TSC_ADD_TO(%ecx, CPU_INTRSTAT)
1388
1389	/ if there is still an interrupt thread underneath this one
1390	/ then the interrupt was never blocked and the return is fairly
1391	/ simple.  Otherwise jump to softintr_thread_exit.
1392	/ softintr_thread_exit expect esi to be curthread & ebx to be ipl.
1393	cmpl	$0, T_INTR(%esi)
1394	je	softintr_thread_exit
1395
1396	/
1397	/ link the thread back onto the interrupt thread pool
1398	LINK_INTR_THREAD(%ebx, %esi, %edx)
1399
1400	/ set the thread state to free so kmdb doesn't see it
1401	movl	$FREE_THREAD, T_STATE(%esi)
1402	/
1403	/ Switch back to the interrupted thread
1404	movl	T_INTR(%esi), %ecx
1405	movl	%ecx, CPU_THREAD(%ebx)
1406	movl	T_SP(%ecx), %esp	/* restore stack pointer */
1407	movl	%esp, %ebp
1408
1409	/ If we are returning to an interrupt thread, store a starting
1410	/ timestamp in the thread structure.
1411	testw	$T_INTR_THREAD, T_FLAGS(%ecx)
1412	jz	0f
1413_tsc_patch14:
1414	nop; nop			/* patched to rdtsc if available */
1415	TSC_MOV(%ecx, T_INTR_START)
14160:
1417	movl	CPU_BASE_SPL(%ebx), %eax
1418	cmpl	%eax, %edi		/* if (oldipl >= basespl) */
1419	jae	softintr_restore_ipl	/* then use oldipl */
1420	movl	%eax, %edi		/* else use basespl */
1421softintr_restore_ipl:
1422	movl	%edi, CPU_PRI(%ebx) /* set IPL to old level */
1423	pushl	%edi
1424	call	*setspl
1425	popl	%eax
1426dosoftint_again:
1427	movl	CPU_SOFTINFO(%ebx), %edx /* any pending software interrupts */
1428	orl	%edx, %edx
1429	jz	_sys_rtt
1430	jmp	dosoftint		/* process more software interrupts */
1431
1432softintr_thread_exit:
1433	/
1434	/ Put thread back on the interrupt thread list.
1435	/ As a reminder, the regs at this point are
1436	/	%esi	interrupt thread
1437
1438	/
1439	/ This was an interrupt thread, so set CPU's base SPL level
1440	/ set_base_spl only uses %eax.
1441	/
1442	call	set_base_spl		/* interrupt vector already on stack */
1443	/
1444	/ Set the thread state to free so kmdb doesn't see it
1445	/
1446	movl	$FREE_THREAD, T_STATE(%esi)
1447	/
1448	/ Put thread on either the interrupt pool or the free pool and
1449	/ call swtch() to resume another thread.
1450	/
1451	LOADCPU(%ebx)
1452	LINK_INTR_THREAD(%ebx, %esi, %edx)
1453	call	splhigh			/* block all intrs below lock lvl */
1454	call	swtch
1455	/ swtch() shouldn't return
1456	SET_SIZE(dosoftint)
1457
1458#endif	/* __i386 */
1459#endif	/* __lint */
1460