| /* SPDX-License-Identifier: GPL-2.0 */ |
| // Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd. |
| |
| #include <linux/linkage.h> |
| #include <abi/entry.h> |
| |
| .text |
| |
| /* |
| * int csky_cmpxchg(int oldval, int newval, int *ptr) |
| * |
| * If *ptr != oldval && return 1, |
| * else *ptr = newval return 0. |
| */ |
| ENTRY(csky_cmpxchg) |
| USPTOKSP |
| |
| RD_MEH a3 |
| WR_MEH a3 |
| |
| mfcr a3, epc |
| addi a3, TRAP0_SIZE |
| |
| subi sp, 16 |
| stw a3, (sp, 0) |
| mfcr a3, epsr |
| stw a3, (sp, 4) |
| mfcr a3, usp |
| stw a3, (sp, 8) |
| |
| psrset ee |
| #ifdef CONFIG_CPU_HAS_LDSTEX |
| 1: |
| ldex a3, (a2) |
| cmpne a0, a3 |
| bt16 2f |
| mov a3, a1 |
| stex a3, (a2) |
| bez a3, 1b |
| 2: |
| sync.is |
| #else |
| GLOBAL(csky_cmpxchg_ldw) |
| ldw a3, (a2) |
| cmpne a0, a3 |
| bt16 3f |
| GLOBAL(csky_cmpxchg_stw) |
| stw a1, (a2) |
| 3: |
| #endif |
| mvc a0 |
| ldw a3, (sp, 0) |
| mtcr a3, epc |
| ldw a3, (sp, 4) |
| mtcr a3, epsr |
| ldw a3, (sp, 8) |
| mtcr a3, usp |
| addi sp, 16 |
| KSPTOUSP |
| rte |
| END(csky_cmpxchg) |
