1/* 2 * Copyright (c) 2013, Google, Inc. All rights reserved 3 * 4 * Permission is hereby granted, free of charge, to any person obtaining 5 * a copy of this software and associated documentation files 6 * (the "Software"), to deal in the Software without restriction, 7 * including without limitation the rights to use, copy, modify, merge, 8 * publish, distribute, sublicense, and/or sell copies of the Software, 9 * and to permit persons to whom the Software is furnished to do so, 10 * subject to the following conditions: 11 * 12 * The above copyright notice and this permission notice shall be 13 * included in all copies or substantial portions of the Software. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 16 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 17 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. 18 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY 19 * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, 20 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE 21 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 22 */ 23 24#include <asm.h> 25 26#define MODE_SVC 0x13 27 28.syntax unified 29 30/* ARM syscall ABI 31 * =============== 32 * Only syscalls with 4 args (max) are currently supported 33 * r0-r3 = args 34 * r0-r1 = return value (r0 only if 32-bit retval) 35 * r12 = syscall number, expected to be trashed. 36 * syscalls run with interrupts enabled 37 */ 38FUNCTION (arm_syscall) 39 srsdb sp!, #MODE_SVC 40 sub sp, sp, #8 41 stmia sp, { r13-r14 }^ 42 43 cpsie iaf 44 45 ldr r14, =nr_syscalls 46 ldr r14, [r14] 47 cmp r12, r14 48 49 ldrlo r14, =syscall_table 50 ldrlo r14, [r14, r12, lsl#2] 51 rsbslo r12, r14, #1 /* This will set the same flags as the cmp above */ 52 ldrhs r14,=sys_undefined 53 blx r14 54 55 cpsid iaf 56 57 ldmia sp, { r13-r14 }^ 58 add sp, sp, #8 59 rfeia sp! 60