2 * Copyright (c) 1989, 1990 William F. Jolitz.
3 * Copyright (c) 1990 The Regents of the University of California.
6 * This code is derived from software contributed to Berkeley by
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
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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 the University of
20 * California, Berkeley and its contributors.
21 * 4. Neither the name of the University nor the names of its contributors
22 * may be used to endorse or promote products derived from this software
23 * without specific prior written permission.
25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
39 * $FreeBSD: src/sys/i386/isa/ipl.s,v 1.32.2.3 2002/05/16 16:03:56 bde Exp $
45 * Vector interrupt control section
47 * cpl - Current interrupt disable mask
48 * *_imask - Interrupt masks for various spl*() functions
49 * ipending - Pending interrupts (set when a masked interrupt occurs)
55 /* current priority (all off) */
57 _cpl: .long HWI_MASK | SWI_MASK
60 _tty_imask: .long SWI_TTY_MASK
62 _bio_imask: .long SWI_CLOCK_MASK | SWI_CAMBIO_MASK
64 _net_imask: .long SWI_NET_MASK | SWI_CAMNET_MASK
66 _cam_imask: .long SWI_CAMBIO_MASK | SWI_CAMNET_MASK
68 _soft_imask: .long SWI_MASK
70 _softnet_imask: .long SWI_NET_MASK
72 _softtty_imask: .long SWI_TTY_MASK
74 /* pending interrupts blocked by splxxx() */
78 /* set with bits for which queue to service */
84 .long dummynetisr, dummynetisr, dummynetisr, dummynetisr
85 .long dummynetisr, dummynetisr, dummynetisr, dummynetisr
86 .long dummynetisr, dummynetisr, dummynetisr, dummynetisr
87 .long dummynetisr, dummynetisr, dummynetisr, dummynetisr
88 .long dummynetisr, dummynetisr, dummynetisr, dummynetisr
89 .long dummynetisr, dummynetisr, dummynetisr, dummynetisr
90 .long dummynetisr, dummynetisr, dummynetisr, dummynetisr
91 .long dummynetisr, dummynetisr, dummynetisr, dummynetisr
96 * Handle return from interrupts, traps and syscalls.
99 .type _doreti,@function
101 FAKE_MCOUNT(_bintr) /* init "from" _bintr -> _doreti */
102 addl $4,%esp /* discard unit number */
103 popl %eax /* cpl or cml to restore */
106 * Check for pending HWIs and SWIs atomically with restoring cpl
107 * and exiting. The check has to be atomic with exiting to stop
108 * (ipending & ~cpl) changing from zero to nonzero while we're
109 * looking at it (this wouldn't be fatal but it would increase
110 * interrupt latency). Restoring cpl has to be atomic with exiting
111 * so that the stack cannot pile up (the nesting level of interrupt
112 * handlers is limited by the number of bits in cpl).
115 cli /* early to prevent INT deadlock */
119 notl %ecx /* set bit = unmasked level */
123 andl _ipending,%ecx /* set bit = unmasked pending INT */
126 decb _intr_nesting_level
128 /* Check for ASTs that can be handled now. */
129 testl $AST_PENDING,_astpending
131 testl $PSL_VM,TF_EFLAGS(%esp)
138 testb $SEL_RPL_MASK,TF_CS(%esp)
142 * doreti_exit - release MP lock, pop registers, iret.
144 * Note that the syscall trap shotcuts to doreti_syscall_ret.
145 * The segment register pop is a special case, since it may
146 * fault if (for example) a sigreturn specifies bad segment
147 * registers. The fault is handled in trap.c
154 /* release the kernel lock */
155 movl $_mp_lock, %edx /* GIANT_LOCK */
159 .globl doreti_popl_fs
160 .globl doreti_syscall_ret
164 .globl doreti_popl_es
167 .globl doreti_popl_ds
177 .globl doreti_iret_fault
182 .globl doreti_popl_ds_fault
183 doreti_popl_ds_fault:
185 .globl doreti_popl_es_fault
186 doreti_popl_es_fault:
188 .globl doreti_popl_fs_fault
189 doreti_popl_fs_fault:
190 movl $0,TF_ERR(%esp) /* XXX should be the error code */
191 movl $T_PROTFLT,TF_TRAPNO(%esp)
192 jmp alltraps_with_regs_pushed
197 * Enabling interrupts is safe because we haven't restored cpl yet.
198 * %ecx contains the next probable ready interrupt (~cpl & ipending)
201 bsfl %ecx, %ecx /* locate the next dispatchable int */
203 btrl %ecx, _ipending /* is it really still pending? */
204 jnc doreti_next2 /* some intr cleared memory copy */
205 sti /* late to prevent INT deadlock */
208 bsfl %ecx,%ecx /* slow, but not worth optimizing */
210 jnc doreti_next /* some intr cleared memory copy */
213 * Execute handleable interrupt
215 * Set up JUMP to _ihandlers[%ecx] for HWIs.
216 * Set up CALL of _ihandlers[%ecx] for SWIs.
217 * This is a bit early for the SMP case - we have to push %ecx and
218 * %edx, but could push only %ecx and load %edx later.
220 movl _ihandlers(,%ecx,4),%edx
222 jae doreti_swi /* software interrupt handling */
223 cli /* else hardware int handling */
225 movl %eax,_cpl /* same as non-smp case right now */
230 #ifdef APIC_INTR_DIAGNOSTIC
232 incl CNAME(apic_itrace_doreti)(,%ecx,4)
233 #ifdef APIC_INTR_DIAGNOSTIC_IRQ
234 cmpl $APIC_INTR_DIAGNOSTIC_IRQ,%ecx
239 pushl $APIC_ITRACE_DORETI
254 * At least the SWI_CLOCK handler has to run at a possibly strictly
255 * lower cpl, so we have to restore
256 * all the h/w bits in cpl now and have to worry about stack growth.
257 * The worst case is currently (30 Jan 1994) 2 SWI handlers nested
258 * in dying interrupt frames and about 12 HWIs nested in active
259 * interrupt frames. There are only 4 different SWIs and the HWI
260 * and SWI masks limit the nesting further.
262 * The SMP case is currently the same as the non-SMP case.
265 orl imasks(,%ecx,4), %eax /* or in imasks */
266 movl %eax,_cpl /* set cpl for call */
268 orl imasks(,%ecx,4),%eax
272 popl %eax /* cpl to restore */
277 andl $~AST_PENDING,_astpending
279 movl $T_ASTFLT,TF_TRAPNO(%esp)
281 subl %eax,%eax /* recover cpl|cml */
282 movb $1,_intr_nesting_level /* for doreti_next to decrement */
293 call *_netisrs(,%eax,4)
306 * The arg is in a nonstandard place, so swi_dispatcher() can't be called
307 * directly and swi_generic() can't use ENTRY() or MCOUNT.
311 .type _swi_generic,@function
323 #include "i386/isa/apic_ipl.s"
325 #include "i386/isa/icu_ipl.s"