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.global _start
_start:
# START Interrupt Vector Table [[
jmp __PMSIZE-4
jmp watchdog_init
jmp interrupt_0
jmp interrupt_1
jmp interrupt_2
jmp interrupt_3
jmp interrupt_4
jmp interrupt_5
jmp interrupt_6
jmp interrupt_7
jmp interrupt_8
jmp interrupt_9
jmp interrupt_10
jmp interrupt_11
jmp interrupt_12
jmp interrupt_13
jmp interrupt_14
jmp interrupt_15
jmp interrupt_16
jmp interrupt_17
jmp interrupt_18
jmp interrupt_19
jmp interrupt_20
jmp interrupt_21
jmp interrupt_22
jmp interrupt_23
jmp interrupt_24
jmp interrupt_25
jmp interrupt_26
jmp interrupt_27
jmp interrupt_28
jmp interrupt_29
jmp interrupt_30
jmp interrupt_31
jmp __PMSIZE-8
# ]] END Interrupt Vector Table
codestart:
jmp init
.global _exithook
_exithook: # Debugger uses '_exithook' at 0x90 to catch program exit
return
watchdog_init:
ldk $r0,1
init:
ldk $sp,__RAMSIZE
# Disable all interrupts
ldk $r4,0x80
sta.b 0x100e3,$r4
# Initialize DATA by copying from program memory
ldk.l $r4,__data_load_start
ldk.l $r1,__data_load_end
ldk.l $r2,0 # Will use __data after binutils patch
jmp .dscopy
.dsloop:
# Copy PM[$r4] to RAM $r2
lpmi.l $r3,$r4,0
sti.l $r2,0,$r3
add.l $r4,$r4,4
add.l $r2,$r2,4
.dscopy:
cmp.l $r4,$r1
jmpc lt,.dsloop
# Zero BSS
ldk.l $r4,_bss_start
ldk.l $r2,_end
sub.l $r2,$r2,$r4
ldk.l $r1,0
ldk $r3,32764
1:
cmp $r2,$r3
jmpc lt,2f
memset $r4,$r1,$r3
add $r4,$r4,$r3
sub $r2,$r2,$r3
jmp 1b
2:
memset $r4,$r1,$r2
sub.l $sp,$sp,24 # Space for the caller argument frame
call main
.equ EXITEXIT,0x1fffc
.global _exit
_exit:
sta.l EXITEXIT,$r0 # simulator end of test
jmp _exithook
# Macro to construct the interrupt stub code.
# it just saves r0, loads r0 with the int vector
# and branches to interrupt_common.
.macro inth i=0
interrupt_\i:
push $r0 # {
lda $r0,(vector_table + 4 * \i)
jmp interrupt_common
.endm
inth 0
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# On entry: r0, already saved, holds the handler function
interrupt_common:
push $r1 # {
push $r2 # {
push $r3 # {
push $r4 # {
push $r5 # {
push $r6 # {
push $r7 # {
push $r8 # {
push $r9 # {
push $r10 # {
push $r11 # {
push $r12 # {
push $cc # {
calli $r0
pop $cc # }
pop $r12 # }
pop $r11 # }
pop $r10 # }
pop $r9 # }
pop $r8 # }
pop $r7 # }
pop $r6 # }
pop $r5 # }
pop $r4 # }
pop $r3 # }
pop $r2 # }
pop $r1 # }
pop $r0 # } matching push in interrupt_0-31 above
reti
# Null function for unassigned interrupt to point at
.global nullvector
nullvector:
return
.section .data
.global vector_table
vector_table:
.rept 33
.long nullvector
.endr
.section .text
.global __gxx_personality_sj0
__gxx_personality_sj0:
|
