You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
105 lines
3.1 KiB
ArmAsm
105 lines
3.1 KiB
ArmAsm
4 years ago
|
/* *****************************************************************************
|
||
|
|
* The MIT License
|
||
|
|
*
|
||
|
|
* Copyright (c) 2010 Perry Hung.
|
||
|
|
*
|
||
|
|
* Permission is hereby granted, free of charge, to any person obtaining a copy
|
||
|
|
* of this software and associated documentation files (the "Software"), to deal
|
||
|
|
* in the Software without restriction, including without limitation the rights
|
||
|
|
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
||
|
|
* copies of the Software, and to permit persons to whom the Software is
|
||
|
|
* furnished to do so, subject to the following conditions:
|
||
|
|
*
|
||
|
|
* The above copyright notice and this permission notice shall be included in
|
||
|
|
* all copies or substantial portions of the Software.
|
||
|
|
*
|
||
|
|
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
||
|
|
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
||
|
|
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
||
|
|
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
||
|
|
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
||
|
|
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
|
||
|
|
* THE SOFTWARE.
|
||
|
|
* ****************************************************************************/
|
||
|
|
|
||
|
|
# On an exception, push a fake stack thread mode stack frame and redirect
|
||
|
|
# thread execution to a thread mode error handler
|
||
|
|
|
||
|
|
# From RM008:
|
||
|
|
# The SP is decremented by eight words by the completion of the stack push.
|
||
|
|
# Figure 5-1 shows the contents of the stack after an exception pre-empts the
|
||
|
|
# current program flow.
|
||
|
|
#
|
||
|
|
# Old SP--> <previous>
|
||
|
|
# xPSR
|
||
|
|
# PC
|
||
|
|
# LR
|
||
|
|
# r12
|
||
|
|
# r3
|
||
|
|
# r2
|
||
|
|
# r1
|
||
|
|
# SP--> r0
|
||
|
|
|
||
|
|
.text
|
||
|
|
.globl __exc_nmi
|
||
|
|
.weak __exc_nmi
|
||
|
|
.globl __exc_hardfault
|
||
|
|
.weak __exc_hardfault
|
||
|
|
.globl __exc_memmanage
|
||
|
|
.weak __exc_memmanage
|
||
|
|
.globl __exc_busfault
|
||
|
|
.weak __exc_busfault
|
||
|
|
.globl __exc_usagefault
|
||
|
|
.weak __exc_usagefault
|
||
|
|
|
||
|
|
.code 16
|
||
|
|
.thumb_func
|
||
|
|
__exc_nmi:
|
||
|
|
mov r0, #1
|
||
|
|
b __default_exc
|
||
|
|
|
||
|
|
.thumb_func
|
||
|
|
__exc_hardfault:
|
||
|
|
mov r0, #2
|
||
|
|
b __default_exc
|
||
|
|
|
||
|
|
.thumb_func
|
||
|
|
__exc_memmanage:
|
||
|
|
mov r0, #3
|
||
|
|
b __default_exc
|
||
|
|
|
||
|
|
.thumb_func
|
||
|
|
__exc_busfault:
|
||
|
|
mov r0, #4
|
||
|
|
b __default_exc
|
||
|
|
|
||
|
|
.thumb_func
|
||
|
|
__exc_usagefault:
|
||
|
|
mov r0, #5
|
||
|
|
b __default_exc
|
||
|
|
|
||
|
|
.thumb_func
|
||
|
|
__default_exc:
|
||
|
|
ldr r2, NVIC_CCR @ Enable returning to thread mode even if there are
|
||
|
|
mov r1 ,#1 @ pending exceptions. See flag NONEBASETHRDENA.
|
||
|
|
str r1, [r2]
|
||
|
|
cpsid i @ Disable global interrupts
|
||
|
|
ldr r2, SYSTICK_CSR @ Disable systick handler
|
||
|
|
mov r1, #0
|
||
|
|
str r1, [r2]
|
||
|
|
ldr r1, CPSR_MASK @ Set default CPSR
|
||
|
|
push {r1}
|
||
|
|
ldr r1, TARGET_PC @ Set target pc
|
||
|
|
push {r1}
|
||
|
|
sub sp, sp, #24 @ Don't care
|
||
|
|
ldr r1, EXC_RETURN @ Return to thread mode
|
||
|
|
mov lr, r1
|
||
|
|
bx lr @ Exception exit
|
||
|
|
|
||
|
|
.align 4
|
||
|
|
CPSR_MASK: .word 0x61000000
|
||
|
|
EXC_RETURN: .word 0xFFFFFFF9
|
||
|
|
TARGET_PC: .word __error
|
||
|
|
NVIC_CCR: .word 0xE000ED14 @ NVIC configuration control register
|
||
|
|
SYSTICK_CSR: .word 0xE000E010 @ Systick control register
|