diff options
Diffstat (limited to 'zap/source/arm64/sys')
| -rw-r--r-- | zap/source/arm64/sys/syscall.s | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/zap/source/arm64/sys/syscall.s b/zap/source/arm64/sys/syscall.s new file mode 100644 index 0000000..df4817d --- /dev/null +++ b/zap/source/arm64/sys/syscall.s @@ -0,0 +1,26 @@ +// Copyright 2022-2023 Gabriel Jensen. +// This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0. +// If a copy of the MPL was not distributed with this file, You can obtain one at <https://mozilla.org/MPL/2.0>. + +.globl zap_syscall + +zap_syscall: + // System calls on ARM64 use the following registers: + // x0 : System call identifier + // x1 : First parameter + // x2 : Second parameter + // x3 : Third parameter + // x4 : Fourth parameter + // x5 : Fifth parameter + // x6 : Sixth parameter + // x0 : Return value + mov x8,x0 // Move the first parameter (the identifier) to x8. + mov x0,x1 // Shift all of the other parameters to the left. + mov x1,x2 + mov x2,x3 + mov x3,x4 + mov x4,x5 + mov x5,x6 + svc 0x0 // Zephyr + // No need to move the return value (already in x0). + ret |