| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/arch/arm/lib/io-readsl.S |
| 3 | * |
| 4 | * Copyright (C) 1995-2000 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 | #include <linux/linkage.h> |
| 11 | #include <asm/assembler.h> |
| 12 | |
| 13 | ENTRY(__raw_readsl) |
| 14 | teq r2, #0 @ do we have to check for the zero len? |
| 15 | moveq pc, lr |
| 16 | ands ip, r1, #3 |
| 17 | bne 3f |
| 18 | |
| 19 | subs r2, r2, #4 |
| 20 | bmi 2f |
| 21 | stmfd sp!, {r4, lr} |
| 22 | 1: ldr r3, [r0, #0] |
| 23 | ldr r4, [r0, #0] |
| 24 | ldr ip, [r0, #0] |
| 25 | ldr lr, [r0, #0] |
| 26 | subs r2, r2, #4 |
| 27 | stmia r1!, {r3, r4, ip, lr} |
| 28 | bpl 1b |
| 29 | ldmfd sp!, {r4, lr} |
| 30 | 2: movs r2, r2, lsl #31 |
| 31 | ldrcs r3, [r0, #0] |
| 32 | ldrcs ip, [r0, #0] |
| 33 | stmcsia r1!, {r3, ip} |
| 34 | ldrne r3, [r0, #0] |
| 35 | strne r3, [r1, #0] |
| 36 | mov pc, lr |
| 37 | |
| 38 | 3: ldr r3, [r0] |
| 39 | cmp ip, #2 |
| 40 | mov ip, r3, get_byte_0 |
| 41 | strb ip, [r1], #1 |
| 42 | bgt 6f |
| 43 | mov ip, r3, get_byte_1 |
| 44 | strb ip, [r1], #1 |
| 45 | beq 5f |
| 46 | mov ip, r3, get_byte_2 |
| 47 | strb ip, [r1], #1 |
| 48 | |
| 49 | 4: subs r2, r2, #1 |
| 50 | mov ip, r3, pull #24 |
| 51 | ldrne r3, [r0] |
| 52 | orrne ip, ip, r3, push #8 |
| 53 | strne ip, [r1], #4 |
| 54 | bne 4b |
| 55 | b 8f |
| 56 | |
| 57 | 5: subs r2, r2, #1 |
| 58 | mov ip, r3, pull #16 |
| 59 | ldrne r3, [r0] |
| 60 | orrne ip, ip, r3, push #16 |
| 61 | strne ip, [r1], #4 |
| 62 | bne 5b |
| 63 | b 7f |
| 64 | |
| 65 | 6: subs r2, r2, #1 |
| 66 | mov ip, r3, pull #8 |
| 67 | ldrne r3, [r0] |
| 68 | orrne ip, ip, r3, push #24 |
| 69 | strne ip, [r1], #4 |
| 70 | bne 6b |
| 71 | |
| 72 | mov r3, ip, get_byte_2 |
| 73 | strb r3, [r1, #2] |
| 74 | 7: mov r3, ip, get_byte_1 |
| 75 | strb r3, [r1, #1] |
| 76 | 8: mov r3, ip, get_byte_0 |
| 77 | strb r3, [r1, #0] |
| 78 | mov pc, lr |