freebsd-dev/sys/i386/isa/icu.s

337 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.
*
* @(#)icu.s 7.2 (Berkeley) 5/21/91
*
* $Id: icu.s,v 1.14 1994/09/19 22:24:31 wollman Exp $
*/
/*
* AT/386
* Vector interrupt control section
*/
/*
* XXX this file should be named ipl.s. All spls are now soft and the
* only thing related to the hardware icu is that the h/w interrupt
* numbers are used without translation in the masks.
*/
#include <net/netisr.h>
.data
.globl _cpl
_cpl: .long HWI_MASK | SWI_MASK /* current priority (all off) */
.globl _imen
_imen: .long HWI_MASK /* interrupt mask enable (all h/w off) */
.globl _stat_imask
_stat_imask: .long (1 << 8)
.globl _tty_imask
_tty_imask: .long 0
.globl _bio_imask
_bio_imask: .long 0
.globl _net_imask
_net_imask: .long 0
.globl _ipending
_ipending: .long 0
.globl _astpending
_astpending: .long 0 /* tells us an AST needs to be taken */
.globl _netisr
_netisr: .long 0 /* set with bits for which queue to service */
vec:
.long vec0, vec1, vec2, vec3, vec4, vec5, vec6, vec7
.long vec8, vec9, vec10, vec11, vec12, vec13, vec14, vec15
.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 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).
*/
movl %eax,%ecx
notl %ecx
cli
andl _ipending,%ecx
jne doreti_unpend
doreti_exit:
movl %eax,_cpl
MEXITCOUNT
popl %es
popl %ds
popal
addl $8,%esp
iret
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.
*/
sti
bsfl %ecx,%ecx /* slow, but not worth optimizing */
btrl %ecx,_ipending
jnc doreti_next /* some intr cleared memory copy */
movl ihandlers(,%ecx,4),%edx
testl %edx,%edx
je doreti_next /* "can't happen" */
cmpl $NHWI,%ecx
jae doreti_swi
cli
movl %eax,_cpl
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.
*/
orl imasks(,%ecx,4),%eax
movl %eax,_cpl
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
movl $T_ASTFLT,(2+8+0)*4(%esp)
call _trap
subl %eax,%eax /* recover cpl */
jmp doreti_next
ALIGN_TEXT
swi_ast_phantom:
/*
* 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
orl $SWI_AST_PENDING,_ipending
jmp doreti_exit /* SWI_AST is highest so we must be done */
/*
* Interrupt priority mechanism
* -- soft splXX masks with group mechanism (cpl)
* -- h/w masks for currently active or unused interrupts (imen)
* -- ipending = active interrupts currently masked by cpl
*/
ENTRY(splz)
/*
* The caller has restored cpl and checked that (ipending & ~cpl)
* is nonzero. We have to repeat the check since if there is an
* interrupt while we're looking, _doreti processing for the
* interrupt will handle all the unmasked pending interrupts
* because we restored early. We're repeating the calculation
* of (ipending & ~cpl) anyway so that the caller doesn't have
* to pass it, so this only costs one "jne". "bsfl %ecx,%ecx"
* is undefined when %ecx is 0 so we can't rely on the secondary
* btrl tests.
*/
movl _cpl,%eax
splz_next:
/*
* We don't need any locking here. (ipending & ~cpl) cannot grow
* while we're looking at it - any interrupt will shrink it to 0.
*/
movl %eax,%ecx
notl %ecx
andl _ipending,%ecx
jne splz_unpend
ret
ALIGN_TEXT
splz_unpend:
bsfl %ecx,%ecx
btrl %ecx,_ipending
jnc splz_next
movl ihandlers(,%ecx,4),%edx
testl %edx,%edx
je splz_next /* "can't happen" */
cmpl $NHWI,%ecx
jae splz_swi
/*
* We would prefer to call the intr handler directly here but that
* doesn't work for badly behaved handlers that want the interrupt
* frame. Also, there's a problem determining the unit number.
* We should change the interface so that the unit number is not
* determined at config time.
*/
jmp *vec(,%ecx,4)
ALIGN_TEXT
splz_swi:
cmpl $SWI_AST,%ecx
je splz_next /* "can't happen" */
pushl %eax
orl imasks(,%ecx,4),%eax
movl %eax,_cpl
call %edx
popl %eax
movl %eax,_cpl
jmp splz_next
/*
* Fake clock interrupt(s) so that they appear to come from our caller instead
* of from here, so that system profiling works.
* XXX do this more generally (for all vectors; look up the C entry point).
* XXX frame bogusness stops us from just jumping to the C entry point.
*/
ALIGN_TEXT
vec0:
popl %eax /* return address */
pushfl
#define KCSEL 8
pushl $KCSEL
pushl %eax
cli
MEXITCOUNT
jmp _Xintr0 /* XXX might need _Xfastintr0 */
ALIGN_TEXT
vec8:
popl %eax
pushfl
pushl $KCSEL
pushl %eax
cli
MEXITCOUNT
jmp _Xintr8 /* XXX might need _Xfastintr8 */
#define BUILD_VEC(irq_num) \
ALIGN_TEXT ; \
vec/**/irq_num: ; \
int $ICU_OFFSET + (irq_num) ; \
ret
BUILD_VEC(1)
BUILD_VEC(2)
BUILD_VEC(3)
BUILD_VEC(4)
BUILD_VEC(5)
BUILD_VEC(6)
BUILD_VEC(7)
BUILD_VEC(9)
BUILD_VEC(10)
BUILD_VEC(11)
BUILD_VEC(12)
BUILD_VEC(13)
BUILD_VEC(14)
BUILD_VEC(15)
ALIGN_TEXT
.globl _dummynetisr
_dummynetisr:
MCOUNT
ret
.data
.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
#define DONET(s) ; \
btrl $s,_netisr ; \
jnc 9f ; \
movl $_netisrs+4*s,%eax ; \
call (%eax) ; \
9:
ALIGN_TEXT
swi_net:
MCOUNT
DONET(0) ; DONET(1) ; DONET(2) ; DONET(3) ; DONET(4)
DONET(5) ; DONET(6) ; DONET(7) ; DONET(8) ; DONET(9)
DONET(10) ; DONET(11) ; DONET(12) ; DONET(13) ; DONET(14)
DONET(15) ; DONET(16) ; DONET(17) ; DONET(18) ; DONET(19)
DONET(20) ; DONET(21) ; DONET(22) ; DONET(23) ; DONET(24)
DONET(25) ; DONET(26) ; DONET(27) ; DONET(28) ; DONET(29)
DONET(30) ; DONET(31)
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 "sio.h"
#if NSIO > 0
jmp _siopoll
#else
ret
#endif