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/* $NetBSD: exception.S,v 1.13 2003/10/31 16:30:15 scw Exp $ */
/*-
* Copyright (c) 1994-1997 Mark Brinicombe.
* Copyright (c) 1994 Brini.
* All rights reserved.
*
* This code is derived from software written for Brini by Mark Brinicombe
*
* 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 Brini.
* 4. The name of the company nor the name of the author may be used to
* endorse or promote products derived from this software without specific
* prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY BRINI ``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 BRINI 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.
*
* RiscBSD kernel project
*
* exception.S
*
* Low level handlers for exception vectors
*
* Created : 24/09/94
*
* Based on kate/display/abort.s
*
*/
#include "assym.s"
#include <machine/asm.h>
#include <machine/armreg.h>
#include <machine/asmacros.h>
__FBSDID("$FreeBSD$");
.text
.align 0
AST_LOCALS
/*
* reset_entry:
*
* Handler for Reset exception.
*/
ASENTRY_NP(reset_entry)
adr r0, Lreset_panicmsg
bl _C_LABEL(panic)
/* NOTREACHED */
Lreset_panicmsg:
.asciz "Reset vector called, LR = 0x%08x"
.balign 4
END(reset_entry)
/*
* swi_entry
*
* Handler for the Software Interrupt exception.
*/
ASENTRY_NP(swi_entry)
STOP_UNWINDING /* Don't unwind past here */
PUSHFRAME
mov r0, sp /* Pass the frame to any function */
mov r6, sp /* Backup the stack pointer */
bic sp, sp, #7 /* Align the stack pointer */
bl _C_LABEL(swi_handler) /* It's a SWI ! */
mov sp, r6 /* Restore the stack */
DO_AST
PULLFRAME
movs pc, lr /* Exit */
END(swi_entry)
/*
* prefetch_abort_entry:
*
* Handler for the Prefetch Abort exception.
*/
ASENTRY_NP(prefetch_abort_entry)
#ifdef __XSCALE__
nop /* Make absolutely sure any pending */
nop /* imprecise aborts have occurred. */
#endif
sub lr, lr, #0x00000004 /* Adjust the lr */
PUSHFRAMEINSVC
ldr r1, Lprefetch_abort_handler_address
adr lr, exception_exit
mov r0, sp /* pass the stack pointer as r0 */
ldr pc, [r1]
Lprefetch_abort_handler_address:
.word _C_LABEL(prefetch_abort_handler_address)
.data
.global _C_LABEL(prefetch_abort_handler_address)
_C_LABEL(prefetch_abort_handler_address):
.word abortprefetch
.text
abortprefetch:
adr r0, abortprefetchmsg
b _C_LABEL(panic)
abortprefetchmsg:
.asciz "abortprefetch"
.align 0
END(prefetch_abort_entry)
/*
* data_abort_entry:
*
* Handler for the Data Abort exception.
*/
ASENTRY_NP(data_abort_entry)
#ifdef __XSCALE__
nop /* Make absolutely sure any pending */
nop /* imprecise aborts have occurred. */
#endif
sub lr, lr, #0x00000008 /* Adjust the lr */
PUSHFRAMEINSVC /* Push trap frame and switch */
/* to SVC32 mode */
ldr r1, Ldata_abort_handler_address
adr lr, exception_exit
mov r0, sp /* pass the stack pointer as r0 */
ldr pc, [r1]
Ldata_abort_handler_address:
.word _C_LABEL(data_abort_handler_address)
.data
.global _C_LABEL(data_abort_handler_address)
_C_LABEL(data_abort_handler_address):
.word abortdata
.text
abortdata:
adr r0, abortdatamsg
b _C_LABEL(panic)
abortdatamsg:
.asciz "abortdata"
.align 0
END(data_abort_entry)
/*
* address_exception_entry:
*
* Handler for the Address Exception exception.
*
* NOTE: This exception isn't really used on arm32. We
* print a warning message to the console and then treat
* it like a Data Abort.
*/
ASENTRY_NP(address_exception_entry)
mrs r1, cpsr_all
mrs r2, spsr_all
mov r3, lr
adr r0, Laddress_exception_msg
bl _C_LABEL(printf) /* XXX CLOBBERS LR!! */
b data_abort_entry
Laddress_exception_msg:
.asciz "Address Exception CPSR=0x%08x SPSR=0x%08x LR=0x%08x\n"
.balign 4
END(address_exception_entry)
/*
* General exception exit handler
* (Placed here to be within range of all the references to it)
*
* It exits straight away if not returning to USR mode.
* This loops around delivering any pending ASTs.
* Interrupts are disabled at suitable points to avoid ASTs
* being posted between testing and exit to user mode.
*
* This function uses PULLFRAMEFROMSVCANDEXIT and DO_AST and can
* only be called if the exception handler used PUSHFRAMEINSVC.
*
* For EABI, don't try to unwind any further than this. This is a
* stopgap measure to avoid getting stuck in a loop in the unwinder,
* which happens because we don't yet provide the proper unwind info
* here that describes which registers are being restored.
*/
ASENTRY_NP(exception_exit)
STOP_UNWINDING
DO_AST
PULLFRAMEFROMSVCANDEXIT
END(exception_exit)
/*
* undefined_entry:
*
* Handler for the Undefined Instruction exception.
*
* We indirect the undefined vector via the handler address
* in the data area. Entry to the undefined handler must
* look like direct entry from the vector.
*/
ASENTRY_NP(undefined_entry)
stmfd sp!, {r0, r1}
ldr r0, Lundefined_handler_indirection
ldr r1, [sp], #0x0004
str r1, [r0, #0x0000]
ldr r1, [sp], #0x0004
str r1, [r0, #0x0004]
ldmia r0, {r0, r1, pc}
Lundefined_handler_indirection:
.word Lundefined_handler_indirection_data
END(undefined_entry)
/*
* assembly bounce code for calling the kernel
* undefined instruction handler. This uses
* a standard trap frame and is called in SVC mode.
*/
ENTRY_NP(undefinedinstruction_bounce)
PUSHFRAMEINSVC
mov r0, sp
adr lr, exception_exit
b _C_LABEL(undefinedinstruction)
.data
.align 0
/*
* Indirection data
* 2 words use for preserving r0 and r1
* 3rd word contains the undefined handler address.
*/
Lundefined_handler_indirection_data:
.word 0
.word 0
.global _C_LABEL(undefined_handler_address)
_C_LABEL(undefined_handler_address):
.word _C_LABEL(undefinedinstruction_bounce)
END(undefinedinstruction_bounce)
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