freebsd-skq/sys/i386/isa/ipl.s
Matthew Dillon 7da240d003 This should fix the lockups people have been experiencing. I muffed up
giving astpending two flag bits.  A cmpl $0 had to turn into a bit test.

Many thanks to: Alain Thivillon <Alain.Thivillon@hsc.fr>
2000-03-29 09:07:47 +00:00

324 lines
8.6 KiB
ArmAsm

/*-
* Copyright (c) 1989, 1990 William F. Jolitz.
* Copyright (c) 1990 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* William Jolitz.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)ipl.s
*
* $FreeBSD$
*/
/*
* AT/386
* Vector interrupt control section
*
* cpl - Current interrupt disable mask
* *_imask - Interrupt masks for various spl*() functions
* ipending - Pending interrupts (set when a masked interrupt occurs)
*/
.data
ALIGN_DATA
/* current priority (all off) */
.globl _cpl
_cpl: .long HWI_MASK | SWI_MASK
.globl _tty_imask
_tty_imask: .long SWI_TTY_MASK
.globl _bio_imask
_bio_imask: .long SWI_CLOCK_MASK | SWI_CAMBIO_MASK
.globl _net_imask
_net_imask: .long SWI_NET_MASK | SWI_CAMNET_MASK
.globl _cam_imask
_cam_imask: .long SWI_CAMBIO_MASK | SWI_CAMNET_MASK
.globl _soft_imask
_soft_imask: .long SWI_MASK
.globl _softnet_imask
_softnet_imask: .long SWI_NET_MASK
.globl _softtty_imask
_softtty_imask: .long SWI_TTY_MASK
/* pending interrupts blocked by splxxx() */
.globl _ipending
_ipending: .long 0
/* set with bits for which queue to service */
.globl _netisr
_netisr: .long 0
.globl _netisrs
_netisrs:
.long dummynetisr, dummynetisr, dummynetisr, dummynetisr
.long dummynetisr, dummynetisr, dummynetisr, dummynetisr
.long dummynetisr, dummynetisr, dummynetisr, dummynetisr
.long dummynetisr, dummynetisr, dummynetisr, dummynetisr
.long dummynetisr, dummynetisr, dummynetisr, dummynetisr
.long dummynetisr, dummynetisr, dummynetisr, dummynetisr
.long dummynetisr, dummynetisr, dummynetisr, dummynetisr
.long dummynetisr, dummynetisr, dummynetisr, dummynetisr
.text
/*
* Handle return from interrupts, traps and syscalls.
*/
SUPERALIGN_TEXT
.type _doreti,@function
_doreti:
FAKE_MCOUNT(_bintr) /* init "from" _bintr -> _doreti */
addl $4,%esp /* discard unit number */
popl %eax /* cpl or cml to restore */
doreti_next:
/*
* Check for pending HWIs and SWIs atomically with restoring cpl
* and exiting. The check has to be atomic with exiting to stop
* (ipending & ~cpl) changing from zero to nonzero while we're
* looking at it (this wouldn't be fatal but it would increase
* interrupt latency). Restoring cpl has to be atomic with exiting
* so that the stack cannot pile up (the nesting level of interrupt
* handlers is limited by the number of bits in cpl).
*/
#ifdef SMP
cli /* early to prevent INT deadlock */
doreti_next2:
#endif
movl %eax,%ecx
notl %ecx /* set bit = unmasked level */
#ifndef SMP
cli
#endif
andl _ipending,%ecx /* set bit = unmasked pending INT */
jne doreti_unpend
movl %eax,_cpl
decb _intr_nesting_level
/* Check for ASTs that can be handled now. */
testl $AST_PENDING,_astpending
je doreti_exit
testb $SEL_RPL_MASK,TF_CS(%esp)
jne doreti_ast
testl $PSL_VM,TF_EFLAGS(%esp)
je doreti_exit
cmpl $1,_in_vm86call
jne doreti_ast
/*
* doreti_exit - release MP lock, pop registers, iret.
*
* Note that the syscall trap shotcuts to doreti_syscall_ret.
* The segment register pop is a special case, since it may
* fault if (for example) a sigreturn specifies bad segment
* registers. The fault is handled in trap.c
*/
doreti_exit:
MEXITCOUNT
#ifdef SMP
/* release the kernel lock */
movl $_mp_lock, %edx /* GIANT_LOCK */
call _MPrellock_edx
#endif /* SMP */
.globl doreti_popl_fs
.globl doreti_syscall_ret
doreti_syscall_ret:
doreti_popl_fs:
popl %fs
.globl doreti_popl_es
doreti_popl_es:
popl %es
.globl doreti_popl_ds
doreti_popl_ds:
popl %ds
popal
addl $8,%esp
.globl doreti_iret
doreti_iret:
iret
ALIGN_TEXT
.globl doreti_iret_fault
doreti_iret_fault:
subl $8,%esp
pushal
pushl %ds
.globl doreti_popl_ds_fault
doreti_popl_ds_fault:
pushl %es
.globl doreti_popl_es_fault
doreti_popl_es_fault:
pushl %fs
.globl doreti_popl_fs_fault
doreti_popl_fs_fault:
movl $0,TF_ERR(%esp) /* XXX should be the error code */
movl $T_PROTFLT,TF_TRAPNO(%esp)
jmp alltraps_with_regs_pushed
ALIGN_TEXT
doreti_unpend:
/*
* Enabling interrupts is safe because we haven't restored cpl yet.
* %ecx contains the next probable ready interrupt (~cpl & ipending)
*/
#ifdef SMP
bsfl %ecx, %ecx /* locate the next dispatchable int */
lock
btrl %ecx, _ipending /* is it really still pending? */
jnc doreti_next2 /* some intr cleared memory copy */
sti /* late to prevent INT deadlock */
#else
sti
bsfl %ecx,%ecx /* slow, but not worth optimizing */
btrl %ecx,_ipending
jnc doreti_next /* some intr cleared memory copy */
#endif /* SMP */
/*
* Execute handleable interrupt
*
* Set up JUMP to _ihandlers[%ecx] for HWIs.
* Set up CALL of _ihandlers[%ecx] for SWIs.
* This is a bit early for the SMP case - we have to push %ecx and
* %edx, but could push only %ecx and load %edx later.
*/
movl _ihandlers(,%ecx,4),%edx
cmpl $NHWI,%ecx
jae doreti_swi /* software interrupt handling */
cli /* else hardware int handling */
#ifdef SMP
movl %eax,_cpl /* same as non-smp case right now */
#else
movl %eax,_cpl
#endif
MEXITCOUNT
#ifdef APIC_INTR_DIAGNOSTIC
lock
incl CNAME(apic_itrace_doreti)(,%ecx,4)
#ifdef APIC_INTR_DIAGNOSTIC_IRQ
cmpl $APIC_INTR_DIAGNOSTIC_IRQ,%ecx
jne 9f
pushl %eax
pushl %ecx
pushl %edx
pushl $APIC_ITRACE_DORETI
call log_intr_event
addl $4,%esp
popl %edx
popl %ecx
popl %eax
9:
#endif
#endif
jmp %edx
ALIGN_TEXT
doreti_swi:
pushl %eax
/*
* At least the SWI_CLOCK handler has to run at a possibly strictly
* lower cpl, so we have to restore
* all the h/w bits in cpl now and have to worry about stack growth.
* The worst case is currently (30 Jan 1994) 2 SWI handlers nested
* in dying interrupt frames and about 12 HWIs nested in active
* interrupt frames. There are only 4 different SWIs and the HWI
* and SWI masks limit the nesting further.
*
* The SMP case is currently the same as the non-SMP case.
*/
#ifdef SMP
orl imasks(,%ecx,4), %eax /* or in imasks */
movl %eax,_cpl /* set cpl for call */
#else
orl imasks(,%ecx,4),%eax
movl %eax,_cpl
#endif
call %edx
popl %eax /* cpl to restore */
jmp doreti_next
ALIGN_TEXT
doreti_ast:
andl $~AST_PENDING,_astpending
sti
movl $T_ASTFLT,TF_TRAPNO(%esp)
call _trap
subl %eax,%eax /* recover cpl|cml */
movb $1,_intr_nesting_level /* for doreti_next to decrement */
jmp doreti_next
ALIGN_TEXT
swi_net:
MCOUNT
bsfl _netisr,%eax
je swi_net_done
swi_net_more:
btrl %eax,_netisr
jnc swi_net_next
call *_netisrs(,%eax,4)
swi_net_next:
bsfl _netisr,%eax
jne swi_net_more
swi_net_done:
ret
ALIGN_TEXT
dummynetisr:
MCOUNT
ret
/*
* The arg is in a nonstandard place, so swi_dispatcher() can't be called
* directly and swi_generic() can't use ENTRY() or MCOUNT.
*/
ALIGN_TEXT
.globl _swi_generic
.type _swi_generic,@function
_swi_generic:
pushl %ecx
FAKE_MCOUNT(4(%esp))
call _swi_dispatcher
popl %ecx
ret
ENTRY(swi_null)
ret
#ifdef APIC_IO
#include "i386/isa/apic_ipl.s"
#else
#include "i386/isa/icu_ipl.s"
#endif /* APIC_IO */