| Jean-Christophe PLAGNIOL-VILLARD | 958f7da | 2009-06-13 20:50:02 +0200 | [diff] [blame] | 1 | /* |
| 2 | * include/asm-arm/macro.h |
| 3 | * |
| 4 | * Copyright (C) 2009 Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> |
| 5 | * |
| 6 | * See file CREDITS for list of people who contributed to this |
| 7 | * project. |
| 8 | * |
| 9 | * This program is free software; you can redistribute it and/or |
| 10 | * modify it under the terms of the GNU General Public License as |
| 11 | * published by the Free Software Foundation; either version 2 of |
| 12 | * the License, or (at your option) any later version. |
| 13 | * |
| 14 | * This program is distributed in the hope that it will be useful, |
| 15 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 16 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 17 | * GNU General Public License for more details. |
| 18 | * |
| 19 | * You should have received a copy of the GNU General Public License |
| 20 | * along with this program; if not, write to the Free Software |
| 21 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, |
| 22 | * MA 02111-1307 USA |
| 23 | */ |
| 24 | |
| 25 | #ifndef __ASM_ARM_MACRO_H__ |
| 26 | #define __ASM_ARM_MACRO_H__ |
| 27 | #ifdef __ASSEMBLY__ |
| 28 | |
| 29 | /* |
| 30 | * These macros provide a convenient way to write 8, 16 and 32 bit data |
| 31 | * to any address. |
| 32 | * Registers r4 and r5 are used, any data in these registers are |
| 33 | * overwritten by the macros. |
| 34 | * The macros are valid for any ARM architecture, they do not implement |
| 35 | * any memory barriers so caution is recommended when using these when the |
| 36 | * caches are enabled or on a multi-core system. |
| 37 | */ |
| 38 | |
| 39 | .macro write32, addr, data |
| 40 | ldr r4, =\addr |
| 41 | ldr r5, =\data |
| 42 | str r5, [r4] |
| 43 | .endm |
| 44 | |
| 45 | .macro write16, addr, data |
| 46 | ldr r4, =\addr |
| 47 | ldrh r5, =\data |
| 48 | strh r5, [r4] |
| 49 | .endm |
| 50 | |
| 51 | .macro write8, addr, data |
| 52 | ldr r4, =\addr |
| 53 | ldrb r5, =\data |
| 54 | strb r5, [r4] |
| 55 | .endm |
| 56 | |
| 57 | /* |
| 58 | * This macro generates a loop that can be used for delays in the code. |
| 59 | * Register r4 is used, any data in this register is overwritten by the |
| 60 | * macro. |
| 61 | * The macro is valid for any ARM architeture. The actual time spent in the |
| 62 | * loop will vary from CPU to CPU though. |
| 63 | */ |
| 64 | |
| 65 | .macro wait_timer, time |
| 66 | ldr r4, =\time |
| 67 | 1: |
| 68 | nop |
| 69 | subs r4, r4, #1 |
| 70 | bcs 1b |
| 71 | .endm |
| 72 | |
| 73 | #endif /* __ASSEMBLY__ */ |
| 74 | #endif /* __ASM_ARM_MACRO_H__ */ |