# XSTORMY16 startup code
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# XSTORMY16 startup code
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# Interrupt vectors at 0x8000.
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# Interrupt vectors at 0x8000.
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.section .int_vec,"ax"
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.section .int_vec,"ax"
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.global _start
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.global _start
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.align 1
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.align 1
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_start:
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_start:
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;; Reset, watchdog timer interrupt
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;; Reset, watchdog timer interrupt
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jmpf _int_reset
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jmpf _int_reset
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;; base timer interrupt
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;; base timer interrupt
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jmpf _int_basetimer
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jmpf _int_basetimer
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;; timer 0
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;; timer 0
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jmpf _int_timer0
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jmpf _int_timer0
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;; timer 1
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;; timer 1
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jmpf _int_timer1
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jmpf _int_timer1
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;; SIO0 interrupt
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;; SIO0 interrupt
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jmpf _int_sio0
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jmpf _int_sio0
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;; SIO1 interrupt
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;; SIO1 interrupt
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jmpf _int_sio1
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jmpf _int_sio1
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;; port0 interrupt
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;; port0 interrupt
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jmpf _int_port0
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jmpf _int_port0
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;; port1 interrupt
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;; port1 interrupt
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jmpf _int_port1
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jmpf _int_port1
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# Reset code, set up memory and call main.
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# Reset code, set up memory and call main.
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.section .rodata
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.section .rodata
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2: .word __rdata
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2: .word __rdata
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.text
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.text
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_int_reset:
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_int_reset:
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;; Set up the stack pointer.
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;; Set up the stack pointer.
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mov r0,#__stack
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mov r0,#__stack
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bz r0,#0,0f
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bz r0,#0,0f
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mov sp,r0
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mov sp,r0
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0:
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0:
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;; Zero the data space
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;; Zero the data space
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mov r0,#_edata
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mov r0,#_edata
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mov r1,#_end
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mov r1,#_end
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mov r2,#0
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mov r2,#0
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0: mov.w (r0++),r2
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0: mov.w (r0++),r2
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blt r0,r1,0b
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blt r0,r1,0b
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;; Copy data from ROM into RAM. ROM area may be above 64k,
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;; Copy data from ROM into RAM. ROM area may be above 64k,
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;; but RAM may not.
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;; but RAM may not.
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mov r1,#__data
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mov r1,#__data
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mov r3,#_edata
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mov r3,#_edata
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mov r4,#2b
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mov r4,#2b
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mov.w r0,(r4++)
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mov.w r0,(r4++)
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mov.w r2,(r4)
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mov.w r2,(r4)
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mov r8,r2
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mov r8,r2
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;; If _data == _rdata there's no need to copy anything.
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;; If _data == _rdata there's no need to copy anything.
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bnz r0,r1,0f
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bnz r0,r1,0f
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bz r2,#0,1f
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bz r2,#0,1f
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0: movf.w r2,(r0++)
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0: movf.w r2,(r0++)
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bnz r0,#0,2f
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bnz r0,#0,2f
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add r8,#1
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add r8,#1
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2: mov.w (r1++),r2
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2: mov.w (r1++),r2
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blt r1,r3,0b
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blt r1,r3,0b
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1:
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1:
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;; Call hardware init routine
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;; Call hardware init routine
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callf _hwinit
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callf _hwinit
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;; Call initialization routines
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;; Call initialization routines
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callf _init
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callf _init
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;; Set up fini routines to be called from exit
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;; Set up fini routines to be called from exit
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mov r2,#@fptr(_fini)
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mov r2,#@fptr(_fini)
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callf atexit
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callf atexit
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;; Call main() with empty argc/argv/envp
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;; Call main() with empty argc/argv/envp
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mov r2,#0
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mov r2,#0
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mov r3,#0
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mov r3,#0
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mov r4,#0
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mov r4,#0
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callf main
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callf main
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;; Exit.
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;; Exit.
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callf exit
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callf exit
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;; Should never reach this code.
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;; Should never reach this code.
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halt
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halt
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1: .size _int_reset,1b-_int_reset
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1: .size _int_reset,1b-_int_reset
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# Stub interrupt routines.
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# Stub interrupt routines.
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.globl _int_timer0
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.globl _int_timer0
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.weak _int_timer0
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.weak _int_timer0
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.globl _int_timer1
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.globl _int_timer1
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.weak _int_timer1
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.weak _int_timer1
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.globl _int_sio0
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.globl _int_sio0
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.weak _int_sio0
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.weak _int_sio0
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.globl _int_sio1
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.globl _int_sio1
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.weak _int_sio1
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.weak _int_sio1
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.globl _int_port0
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.globl _int_port0
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.weak _int_port0
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.weak _int_port0
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.globl _int_port1
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.globl _int_port1
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.weak _int_port1
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.weak _int_port1
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.globl _int_basetimer
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.globl _int_basetimer
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.weak _int_basetimer
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.weak _int_basetimer
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_int_timer0:
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_int_timer0:
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_int_timer1:
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_int_timer1:
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_int_sio0:
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_int_sio0:
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_int_sio1:
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_int_sio1:
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_int_port0:
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_int_port0:
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_int_port1:
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_int_port1:
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_int_basetimer:
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_int_basetimer:
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iret
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iret
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1: .size _int_timer0,1b-_int_timer0
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1: .size _int_timer0,1b-_int_timer0
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# Stub hardware init
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# Stub hardware init
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.globl _hwinit
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.globl _hwinit
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.weak _hwinit
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.weak _hwinit
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_hwinit:
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_hwinit:
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ret
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ret
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1: .size _int_hwinit,1b-_int_hwinit
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1: .size _int_hwinit,1b-_int_hwinit
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# The first word in .data has address 0, so it's not a good
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# The first word in .data has address 0, so it's not a good
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# idea to use it as its address conflicts with NULL.
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# idea to use it as its address conflicts with NULL.
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# Place a HALT instruction there to try to catch NULL pointer
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# Place a HALT instruction there to try to catch NULL pointer
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# dereferences.
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# dereferences.
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.data
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.data
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halt
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halt
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