34162fc615
Preliminary support for the INTR_SIMPLELOCK algorithm, disabled. Note that this code is NOT ready.
377 lines
9.4 KiB
ArmAsm
377 lines
9.4 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
|
|
*
|
|
* $Id: ipl.s,v 1.16 1997/08/28 09:51:32 smp Exp smp $
|
|
*/
|
|
|
|
|
|
#ifdef REAL_ICPL
|
|
|
|
#define ICPL_LOCK CPL_LOCK
|
|
#define ICPL_UNLOCK CPL_UNLOCK
|
|
#define FAST_ICPL_UNLOCK movl $0, _cpl_lock
|
|
|
|
#else /* REAL_ICPL */
|
|
|
|
#define ICPL_LOCK
|
|
#define ICPL_UNLOCK
|
|
#define FAST_ICPL_UNLOCK
|
|
|
|
#endif /* REAL_ICPL */
|
|
|
|
/*
|
|
* AT/386
|
|
* Vector interrupt control section
|
|
*/
|
|
|
|
.data
|
|
ALIGN_DATA
|
|
|
|
/* current priority (all off) */
|
|
.globl _cpl
|
|
_cpl: .long HWI_MASK | SWI_MASK
|
|
|
|
.globl _tty_imask
|
|
_tty_imask: .long 0
|
|
.globl _bio_imask
|
|
_bio_imask: .long 0
|
|
.globl _net_imask
|
|
_net_imask: .long 0
|
|
.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
|
|
_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 */
|
|
movl %eax, %edx /* preserve cpl while getting lock */
|
|
ICPL_LOCK
|
|
movl %edx, %eax
|
|
#endif
|
|
movl %eax,%ecx
|
|
#ifdef INTR_SIMPLELOCK
|
|
orl _cpl, %ecx /* add cpl to cml */
|
|
#endif
|
|
notl %ecx /* set bit = unmasked level */
|
|
#ifndef SMP
|
|
cli
|
|
#endif
|
|
andl _ipending,%ecx /* set bit = unmasked pending INT */
|
|
jne doreti_unpend
|
|
doreti_exit:
|
|
#ifdef INTR_SIMPLELOCK
|
|
movl %eax, _cml
|
|
#else
|
|
movl %eax,_cpl
|
|
#endif
|
|
FAST_ICPL_UNLOCK /* preserves %eax */
|
|
MPLOCKED decb _intr_nesting_level
|
|
MEXITCOUNT
|
|
#ifdef VM86
|
|
#ifdef INTR_SIMPLELOCK
|
|
/* XXX INTR_SIMPLELOCK needs work */
|
|
#error not ready for vm86
|
|
#endif
|
|
/*
|
|
* XXX
|
|
* Sometimes when attempting to return to vm86 mode, cpl is not
|
|
* being reset to 0, so here we force it to 0 before returning to
|
|
* vm86 mode. doreti_stop is a convenient place to set a breakpoint.
|
|
* When the cpl problem is solved, this code can disappear.
|
|
*/
|
|
ICPL_LOCK
|
|
cmpl $0,_cpl
|
|
je 1f
|
|
testl $PSL_VM,TF_EFLAGS(%esp)
|
|
je 1f
|
|
doreti_stop:
|
|
movl $0,_cpl
|
|
nop
|
|
1:
|
|
FAST_ICPL_UNLOCK /* preserves %eax */
|
|
#endif /* VM86 */
|
|
|
|
#ifdef SMP
|
|
#ifdef INTR_SIMPLELOCK
|
|
/**#error code needed here to decide which lock to release, INTR or giant*/
|
|
#endif
|
|
/* release the kernel lock */
|
|
pushl $_mp_lock /* GIANT_LOCK */
|
|
call _MPrellock
|
|
add $4, %esp
|
|
#endif /* SMP */
|
|
|
|
.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:
|
|
movl $0,4+4+32+4(%esp) /* XXX should be the error code */
|
|
movl $T_PROTFLT,4+4+32+0(%esp)
|
|
jmp alltraps_with_regs_pushed
|
|
|
|
ALIGN_TEXT
|
|
doreti_unpend:
|
|
/*
|
|
* Enabling interrupts is safe because we haven't restored cpl yet.
|
|
* The locking from the "btrl" test is probably no longer necessary.
|
|
* We won't miss any new pending interrupts because we will check
|
|
* for them again.
|
|
*/
|
|
#ifdef SMP
|
|
/* we enter with cpl locked */
|
|
bsfl %ecx, %ecx /* slow, but not worth optimizing */
|
|
btrl %ecx, _ipending
|
|
FAST_ICPL_UNLOCK /* preserves %eax */
|
|
sti /* late to prevent INT deadlock */
|
|
#else
|
|
sti
|
|
bsfl %ecx,%ecx /* slow, but not worth optimizing */
|
|
btrl %ecx,_ipending
|
|
#endif /* SMP */
|
|
jnc doreti_next /* some intr cleared memory copy */
|
|
|
|
/*
|
|
* setup call to _Xresume0 thru _Xresume23 for hwi,
|
|
* or swi_tty, swi_net, _softclock, swi_ast for swi.
|
|
*/
|
|
movl ihandlers(,%ecx,4),%edx
|
|
testl %edx,%edx
|
|
je doreti_next /* "can't happen" */
|
|
cmpl $NHWI,%ecx
|
|
jae doreti_swi
|
|
cli
|
|
#ifdef SMP
|
|
pushl %eax /* preserve %eax */
|
|
ICPL_LOCK
|
|
#ifdef INTR_SIMPLELOCK
|
|
popl _cml
|
|
#else
|
|
popl _cpl
|
|
#endif
|
|
FAST_ICPL_UNLOCK
|
|
#else
|
|
movl %eax,_cpl
|
|
#endif
|
|
MEXITCOUNT
|
|
jmp %edx
|
|
|
|
ALIGN_TEXT
|
|
doreti_swi:
|
|
pushl %eax
|
|
/*
|
|
* The SWI_AST handler has to run at cpl = SWI_AST_MASK and the
|
|
* SWI_CLOCK handler at cpl = SWI_CLOCK_MASK, 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.
|
|
*/
|
|
#ifdef SMP
|
|
orl imasks(,%ecx,4), %eax
|
|
cli /* prevent INT deadlock */
|
|
pushl %eax /* save cpl|cmpl */
|
|
ICPL_LOCK
|
|
#ifdef INTR_SIMPLELOCK
|
|
popl _cml /* restore cml */
|
|
#else
|
|
popl _cpl /* restore cpl */
|
|
#endif
|
|
FAST_ICPL_UNLOCK
|
|
sti
|
|
#else
|
|
orl imasks(,%ecx,4),%eax
|
|
movl %eax,_cpl
|
|
#endif
|
|
call %edx
|
|
popl %eax
|
|
jmp doreti_next
|
|
|
|
ALIGN_TEXT
|
|
swi_ast:
|
|
addl $8,%esp /* discard raddr & cpl to get trap frame */
|
|
testb $SEL_RPL_MASK,TRAPF_CS_OFF(%esp)
|
|
je swi_ast_phantom
|
|
swi_ast_user:
|
|
movl $T_ASTFLT,(2+8+0)*4(%esp)
|
|
movb $0,_intr_nesting_level /* finish becoming a trap handler */
|
|
call _trap
|
|
subl %eax,%eax /* recover cpl|cml */
|
|
#ifdef INTR_SIMPLELOCK
|
|
movl %eax, _cpl
|
|
#endif
|
|
movb $1,_intr_nesting_level /* for doreti_next to decrement */
|
|
jmp doreti_next
|
|
|
|
ALIGN_TEXT
|
|
swi_ast_phantom:
|
|
#ifdef VM86
|
|
/*
|
|
* check for ast from vm86 mode. Placed down here so the jumps do
|
|
* not get taken for mainline code.
|
|
*/
|
|
testl $PSL_VM,TF_EFLAGS(%esp)
|
|
jne swi_ast_user
|
|
#endif /* VM86 */
|
|
/*
|
|
* These happen when there is an interrupt in a trap handler before
|
|
* ASTs can be masked or in an lcall handler before they can be
|
|
* masked or after they are unmasked. They could be avoided for
|
|
* trap entries by using interrupt gates, and for lcall exits by
|
|
* using by using cli, but they are unavoidable for lcall entries.
|
|
*/
|
|
cli
|
|
ICPL_LOCK
|
|
orl $SWI_AST_PENDING, _ipending
|
|
/* cpl is unlocked in doreti_exit */
|
|
subl %eax,%eax
|
|
#ifdef INTR_SIMPLELOCK
|
|
movl %eax, _cpl
|
|
#endif
|
|
jmp doreti_exit /* SWI_AST is highest so we must be done */
|
|
|
|
|
|
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
|
|
|
|
/*
|
|
* XXX there should be a registration function to put the handler for the
|
|
* attached driver directly in ihandlers. Then this function will go away.
|
|
*/
|
|
ALIGN_TEXT
|
|
swi_tty:
|
|
MCOUNT
|
|
#include "cy.h"
|
|
#if NCY > 0
|
|
call _cypoll
|
|
#endif
|
|
#include "rc.h"
|
|
#if NRC > 0
|
|
call _rcpoll
|
|
#endif
|
|
#include "sio.h"
|
|
#if NSIO > 0
|
|
jmp _siopoll
|
|
#else
|
|
ret
|
|
#endif
|
|
|
|
#ifdef APIC_IO
|
|
#include "i386/isa/apic_ipl.s"
|
|
#else
|
|
#include "i386/isa/icu_ipl.s"
|
|
#endif /* APIC_IO */
|