| /* 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 |
| mfcr a3, epc |
| addi a3, TRAP0_SIZE |
| |
| subi sp, 8 |
| stw a3, (sp, 0) |
| mfcr a3, epsr |
| stw a3, (sp, 4) |
| |
| 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 |
| 1: |
| ldw a3, (a2) |
| cmpne a0, a3 |
| bt16 3f |
| 2: |
| stw a1, (a2) |
| 3: |
| #endif |
| mvc a0 |
| ldw a3, (sp, 0) |
| mtcr a3, epc |
| ldw a3, (sp, 4) |
| mtcr a3, epsr |
| addi sp, 8 |
| KSPTOUSP |
| rte |
| END(csky_cmpxchg) |
| |
| #ifndef CONFIG_CPU_HAS_LDSTEX |
| /* |
| * Called from tlbmodified exception |
| */ |
| ENTRY(csky_cmpxchg_fixup) |
| mfcr a0, epc |
| lrw a1, 2b |
| cmpne a1, a0 |
| bt 1f |
| subi a1, (2b - 1b) |
| stw a1, (sp, LSAVE_PC) |
| 1: |
| rts |
| END(csky_cmpxchg_fixup) |
| #endif |
