mirror of
git://projects.qi-hardware.com/nn-usb-fpga.git
synced 2025-01-09 23:30:16 +02:00
291 lines
8.6 KiB
ArmAsm
291 lines
8.6 KiB
ArmAsm
/*
|
|
* LatticeMico32 GDB C startup code.
|
|
*
|
|
* 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.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
|
|
*/
|
|
|
|
/* Exception handlers - Must be 32 bytes long. */
|
|
|
|
.section .boot, "ax", @progbits
|
|
|
|
.global _start
|
|
_start:
|
|
_reset_handler:
|
|
bi _crt0
|
|
nop
|
|
nop
|
|
nop
|
|
nop
|
|
nop
|
|
nop
|
|
nop
|
|
|
|
_breakpoint_handler:
|
|
sw (sp+0), ra
|
|
calli _save_all
|
|
sw (sp+128), ba
|
|
mvi r1, 1
|
|
sw (sp+132), r1
|
|
mv r1, sp
|
|
calli _handle_exception
|
|
bi _b_restore_all_and_return
|
|
|
|
_instruction_bus_error_handler:
|
|
sw (sp+0), ra
|
|
calli _save_all
|
|
sw (sp+128), ea
|
|
mvi r1, 2
|
|
sw (sp+132), r1
|
|
mv r1, sp
|
|
calli _handle_exception
|
|
bi _e_restore_all_and_return
|
|
|
|
_watchpoint_handler:
|
|
sw (sp+0), ra
|
|
calli _save_all
|
|
sw (sp+128), ba
|
|
mvi r1, 3
|
|
sw (sp+132), r1
|
|
mv r1, sp
|
|
calli _handle_exception
|
|
bi _b_restore_all_and_return
|
|
|
|
_data_bus_error_handler:
|
|
sw (sp+0), ra
|
|
calli _save_all
|
|
sw (sp+128), ea
|
|
mvi r1, 4
|
|
sw (sp+132), r1
|
|
mv r1, sp
|
|
calli _handle_exception
|
|
bi _e_restore_all_and_return
|
|
|
|
_divide_by_zero_handler:
|
|
sw (sp+0), ra
|
|
calli _save_all
|
|
sw (sp+128), ea
|
|
mvi r1, 5
|
|
sw (sp+132), r1
|
|
mv r1, sp
|
|
calli _handle_exception
|
|
bi _e_restore_all_and_return
|
|
|
|
_interrupt_handler:
|
|
sw (sp+0), ra
|
|
calli _save_all
|
|
sw (sp+128), ea
|
|
mvi r1, 6
|
|
sw (sp+132), r1
|
|
mv r1, sp
|
|
calli _handle_exception
|
|
bi _e_restore_all_and_return
|
|
|
|
_system_call_handler:
|
|
sw (sp+0), ra
|
|
calli _save_all
|
|
sw (sp+128), ea
|
|
mvi r1, 7
|
|
sw (sp+132), r1
|
|
mv r1, sp
|
|
calli _handle_exception
|
|
bi _e_restore_all_and_return
|
|
|
|
/* Program starts here */
|
|
|
|
_crt0:
|
|
/* Clear r0 */
|
|
xor r0, r0, r0
|
|
|
|
/* Clear all other regs (needed so that simulations match) */
|
|
mvi r1, 0
|
|
mvi r2, 0
|
|
mvi r3, 0
|
|
mvi r4, 0
|
|
mvi r5, 0
|
|
mvi r6, 0
|
|
mvi r7, 0
|
|
mvi r8, 0
|
|
mvi r9, 0
|
|
mvi r10, 0
|
|
mvi r11, 0
|
|
mvi r12, 0
|
|
mvi r13, 0
|
|
mvi r14, 0
|
|
mvi r15, 0
|
|
mvi r16, 0
|
|
mvi r17, 0
|
|
mvi r18, 0
|
|
mvi r19, 0
|
|
mvi r20, 0
|
|
mvi r21, 0
|
|
mvi r22, 0
|
|
mvi r23, 0
|
|
mvi r24, 0
|
|
mvi r25, 0
|
|
mvi r26, 0
|
|
mvi r27, 0
|
|
mvi r28, 0
|
|
mvi r29, 0
|
|
mvi r30, 0
|
|
mvi r31, 0
|
|
|
|
/* Setup stack and global pointer */
|
|
mvhi sp, hi(_fstack)
|
|
ori sp, sp, lo(_fstack)
|
|
mvhi gp, hi(_gp)
|
|
ori gp, gp, lo(_gp)
|
|
|
|
/* Clear BSS */
|
|
mvhi r1, hi(_fbss)
|
|
ori r1, r1, lo(_fbss)
|
|
mvhi r3, hi(_ebss)
|
|
ori r3, r3, lo(_ebss)
|
|
.clearBSS:
|
|
be r1, r3, .callMain
|
|
sw (r1+0), r0
|
|
addi r1, r1, 4
|
|
bi .clearBSS
|
|
|
|
.callMain:
|
|
mvi r1, 0
|
|
mvi r2, 0
|
|
mvi r3, 0
|
|
/* Enter debug exception handler */
|
|
mvhi ba, hi(main)
|
|
ori ba, ba, lo(main)
|
|
bi _breakpoint_handler
|
|
|
|
/* Save all registers onto the stack */
|
|
_save_all:
|
|
addi sp, sp, -136
|
|
sw (sp+0), r0
|
|
sw (sp+4), r1
|
|
sw (sp+8), r2
|
|
sw (sp+12), r3
|
|
sw (sp+16), r4
|
|
sw (sp+20), r5
|
|
sw (sp+24), r6
|
|
sw (sp+28), r7
|
|
sw (sp+32), r8
|
|
sw (sp+36), r9
|
|
sw (sp+40), r10
|
|
sw (sp+44), r11
|
|
sw (sp+48), r12
|
|
sw (sp+52), r13
|
|
sw (sp+56), r14
|
|
sw (sp+60), r15
|
|
sw (sp+64), r16
|
|
sw (sp+68), r17
|
|
sw (sp+72), r18
|
|
sw (sp+76), r19
|
|
sw (sp+80), r20
|
|
sw (sp+84), r21
|
|
sw (sp+88), r22
|
|
sw (sp+92), r23
|
|
sw (sp+96), r24
|
|
sw (sp+100), r25
|
|
sw (sp+104), r26
|
|
sw (sp+108), r27
|
|
sw (sp+120), ea
|
|
sw (sp+124), ba
|
|
/* ra and sp need special handling, as they have been modified */
|
|
lw r1, (sp+136)
|
|
sw (sp+116), r1
|
|
mv r1, sp
|
|
addi r1, r1, 136
|
|
sw (sp+112), r1
|
|
ret
|
|
|
|
/* Restore all registers and return from exception */
|
|
_e_restore_all_and_return:
|
|
lw r1, (sp+4)
|
|
lw r2, (sp+8)
|
|
lw r3, (sp+12)
|
|
lw r4, (sp+16)
|
|
lw r5, (sp+20)
|
|
lw r6, (sp+24)
|
|
lw r7, (sp+28)
|
|
lw r8, (sp+32)
|
|
lw r9, (sp+36)
|
|
lw r10, (sp+40)
|
|
lw r11, (sp+44)
|
|
lw r12, (sp+48)
|
|
lw r13, (sp+52)
|
|
lw r14, (sp+56)
|
|
lw r15, (sp+60)
|
|
lw r16, (sp+64)
|
|
lw r17, (sp+68)
|
|
lw r18, (sp+72)
|
|
lw r19, (sp+76)
|
|
lw r20, (sp+80)
|
|
lw r21, (sp+84)
|
|
lw r22, (sp+88)
|
|
lw r23, (sp+92)
|
|
lw r24, (sp+96)
|
|
lw r25, (sp+100)
|
|
lw r26, (sp+104)
|
|
lw r27, (sp+108)
|
|
lw ra, (sp+116)
|
|
lw ba, (sp+124)
|
|
/* Restore EA from PC */
|
|
lw ea, (sp+128)
|
|
/* Stack pointer must be restored last, in case it has been updated */
|
|
lw sp, (sp+112)
|
|
eret
|
|
|
|
/* Restore all registers and return from breakpoint */
|
|
_b_restore_all_and_return:
|
|
lw r1, (sp+4)
|
|
lw r2, (sp+8)
|
|
lw r3, (sp+12)
|
|
lw r4, (sp+16)
|
|
lw r5, (sp+20)
|
|
lw r6, (sp+24)
|
|
lw r7, (sp+28)
|
|
lw r8, (sp+32)
|
|
lw r9, (sp+36)
|
|
lw r10, (sp+40)
|
|
lw r11, (sp+44)
|
|
lw r12, (sp+48)
|
|
lw r13, (sp+52)
|
|
lw r14, (sp+56)
|
|
lw r15, (sp+60)
|
|
lw r16, (sp+64)
|
|
lw r17, (sp+68)
|
|
lw r18, (sp+72)
|
|
lw r19, (sp+76)
|
|
lw r20, (sp+80)
|
|
lw r21, (sp+84)
|
|
lw r22, (sp+88)
|
|
lw r23, (sp+92)
|
|
lw r24, (sp+96)
|
|
lw r25, (sp+100)
|
|
lw r26, (sp+104)
|
|
lw r27, (sp+108)
|
|
lw ra, (sp+116)
|
|
lw ea, (sp+120)
|
|
/* Restore BA from PC */
|
|
lw ba, (sp+128)
|
|
/* Stack pointer must be restored last, in case it has been updated */
|
|
lw sp, (sp+112)
|
|
bret
|