| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame^] | 1 | /* |
| 2 | * linux/arch/arm/lib/copypage-v4.S |
| 3 | * |
| 4 | * Copyright (C) 1995-1999 Russell King |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License version 2 as |
| 8 | * published by the Free Software Foundation. |
| 9 | * |
| 10 | * ASM optimised string functions |
| 11 | * |
| 12 | * This is for CPUs with a writethrough cache and 'flush ID cache' is |
| 13 | * the only supported cache operation. |
| 14 | */ |
| 15 | #include <linux/linkage.h> |
| 16 | #include <linux/init.h> |
| 17 | #include <asm/constants.h> |
| 18 | |
| 19 | .text |
| 20 | .align 5 |
| 21 | /* |
| 22 | * ARMv4 optimised copy_user_page |
| 23 | * |
| 24 | * Since we have writethrough caches, we don't have to worry about |
| 25 | * dirty data in the cache. However, we do have to ensure that |
| 26 | * subsequent reads are up to date. |
| 27 | */ |
| 28 | ENTRY(v4wt_copy_user_page) |
| 29 | stmfd sp!, {r4, lr} @ 2 |
| 30 | mov r2, #PAGE_SZ/64 @ 1 |
| 31 | ldmia r1!, {r3, r4, ip, lr} @ 4 |
| 32 | 1: stmia r0!, {r3, r4, ip, lr} @ 4 |
| 33 | ldmia r1!, {r3, r4, ip, lr} @ 4+1 |
| 34 | stmia r0!, {r3, r4, ip, lr} @ 4 |
| 35 | ldmia r1!, {r3, r4, ip, lr} @ 4 |
| 36 | stmia r0!, {r3, r4, ip, lr} @ 4 |
| 37 | ldmia r1!, {r3, r4, ip, lr} @ 4 |
| 38 | subs r2, r2, #1 @ 1 |
| 39 | stmia r0!, {r3, r4, ip, lr} @ 4 |
| 40 | ldmneia r1!, {r3, r4, ip, lr} @ 4 |
| 41 | bne 1b @ 1 |
| 42 | mcr p15, 0, r2, c7, c7, 0 @ flush ID cache |
| 43 | ldmfd sp!, {r4, pc} @ 3 |
| 44 | |
| 45 | .align 5 |
| 46 | /* |
| 47 | * ARMv4 optimised clear_user_page |
| 48 | * |
| 49 | * Same story as above. |
| 50 | */ |
| 51 | ENTRY(v4wt_clear_user_page) |
| 52 | str lr, [sp, #-4]! |
| 53 | mov r1, #PAGE_SZ/64 @ 1 |
| 54 | mov r2, #0 @ 1 |
| 55 | mov r3, #0 @ 1 |
| 56 | mov ip, #0 @ 1 |
| 57 | mov lr, #0 @ 1 |
| 58 | 1: stmia r0!, {r2, r3, ip, lr} @ 4 |
| 59 | stmia r0!, {r2, r3, ip, lr} @ 4 |
| 60 | stmia r0!, {r2, r3, ip, lr} @ 4 |
| 61 | stmia r0!, {r2, r3, ip, lr} @ 4 |
| 62 | subs r1, r1, #1 @ 1 |
| 63 | bne 1b @ 1 |
| 64 | mcr p15, 0, r2, c7, c7, 0 @ flush ID cache |
| 65 | ldr pc, [sp], #4 |
| 66 | |
| 67 | __INITDATA |
| 68 | |
| 69 | .type v4wt_user_fns, #object |
| 70 | ENTRY(v4wt_user_fns) |
| 71 | .long v4wt_clear_user_page |
| 72 | .long v4wt_copy_user_page |
| 73 | .size v4wt_user_fns, . - v4wt_user_fns |