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/*
* swi_handler.s
*
* Copyright © 2018 Thomas White <taw@bitwiz.org.uk>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
.include "swi_numbers.h"
.global swi_handler
swi_handler:
STMDB R13!, { R12, LR}
LDR R12, [LR, #-4]
BIC R12, R12, #0xff000000
CMP R12, #OS_GetGPIO
BEQ get_gpio
CMP R12, #OS_SetGPIO
BEQ set_gpio
CMP R12, #OS_ClearGPIO
BEQ clear_gpio
CMP R12, #OS_GetCPUID
BEQ get_cpu_id
LDMIA R13!, {R12, PC}^
get_gpio:
STMDB R13!, {R8}
LDR R8, =0x3f200000
LDR R0, [R8, #0x34] @ GPLEV0
LDMIA R13!, {R8}
LDMIA R13!, {R12, PC}^
set_gpio:
STMDB R13!, {R8}
LDR R8, =0x3f200000
STR R1, [R8, #0x1c] @ GPSET0
LDMIA R13!, {R8}
LDMIA R13!, {R12, PC}^
clear_gpio:
STMDB R13!, {R8}
LDR R8, =0x3f200000
STR R1, [R8, #0x28] @ GPCLR0
LDMIA R13!, {R8}
LDMIA R13!, {R12, PC}^
get_cpu_id:
MRC P15, 0, R0, C0, C0, 5
AND R0, R0, #0x0f
LDMIA R13!, {R12, PC}^
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