| 1 | /* $NetBSD: asm_single.h,v 1.10 2022/05/18 13:56:32 andvar Exp $ */ |
| 2 | |
| 3 | /* |
| 4 | * Copyright (c) 1996 Leo Weppelman. |
| 5 | * All rights reserved. |
| 6 | * |
| 7 | * Redistribution and use in source and binary forms, with or without |
| 8 | * modification, are permitted provided that the following conditions |
| 9 | * are met: |
| 10 | * 1. Redistributions of source code must retain the above copyright |
| 11 | * notice, this list of conditions and the following disclaimer. |
| 12 | * 2. Redistributions in binary form must reproduce the above copyright |
| 13 | * notice, this list of conditions and the following disclaimer in the |
| 14 | * documentation and/or other materials provided with the distribution. |
| 15 | * |
| 16 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| 17 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| 18 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| 19 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
| 20 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| 21 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| 22 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| 23 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 24 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| 25 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 26 | */ |
| 27 | |
| 28 | #ifndef _M68K_ASM_SINGLE_H |
| 29 | #define _M68K_ASM_SINGLE_H |
| 30 | /* |
| 31 | * Provide bit manipulation macro's that resolve to a single instruction. |
| 32 | * These can be considered atomic on single processor architectures when |
| 33 | * no page faults can occur when accessing <var>. |
| 34 | * There primary use is to avoid race conditions when manipulating device |
| 35 | * registers. |
| 36 | */ |
| 37 | |
| 38 | #define single_inst_bset_b(var, bit) \ |
| 39 | __asm volatile ("orb %1,%0" \ |
| 40 | : "+m" (var) \ |
| 41 | : "di" ((u_char)bit)) |
| 42 | |
| 43 | #define single_inst_bclr_b(var, bit) \ |
| 44 | __asm volatile ("andb %1,%0" \ |
| 45 | : "+m" (var) \ |
| 46 | : "di" ((u_char)~(bit))) |
| 47 | |
| 48 | |
| 49 | #define single_inst_bset_w(var, bit) \ |
| 50 | __asm volatile ("orw %1,%0" \ |
| 51 | : "+m" (var) \ |
| 52 | : "di" ((u_short)bit)) |
| 53 | |
| 54 | #define single_inst_bclr_w(var, bit) \ |
| 55 | __asm volatile ("andw %1,%0" \ |
| 56 | : "+m" (var) \ |
| 57 | : "di" ((u_short)~(bit))) |
| 58 | |
| 59 | |
| 60 | #define single_inst_bset_l(var, bit) \ |
| 61 | __asm volatile ("orl %1,%0" \ |
| 62 | : "+m" (var) \ |
| 63 | : "di" ((u_long)bit)) |
| 64 | |
| 65 | #define single_inst_bclr_l(var, bit) \ |
| 66 | __asm volatile ("andl %1,%0" \ |
| 67 | : "+m" (var) \ |
| 68 | : "di" ((u_long)~(bit))) |
| 69 | |
| 70 | #endif /* _M68K_ASM_SINGLE_H */ |