1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * linux/arch/arm/lib/io-readsw-armv4.S 4 * 5 * Copyright (C) 1995-2000 Russell King 6 */ 7 #include <linux/linkage.h> 8 #include <asm/assembler.h> 9 10 .macro pack, rd, hw1, hw2 11 #ifndef __ARMEB__ 12 orr \rd, \hw1, \hw2, lsl #16 13 #else 14 orr \rd, \hw2, \hw1, lsl #16 15 #endif 16 .endm 17 18 .Linsw_align: movs ip, r1, lsl #31 19 bne .Linsw_noalign 20 ldrh ip, [r0] 21 sub r2, r2, #1 22 strh ip, [r1], #2 23 24 ENTRY(__raw_readsw) 25 teq r2, #0 26 reteq lr 27 tst r1, #3 28 bne .Linsw_align 29 30 stmfd sp!, {r4, r5, lr} 31 32 subs r2, r2, #8 33 bmi .Lno_insw_8 34 35 .Linsw_8_lp: ldrh r3, [r0] 36 ldrh r4, [r0] 37 pack r3, r3, r4 38 39 ldrh r4, [r0] 40 ldrh r5, [r0] 41 pack r4, r4, r5 42 43 ldrh r5, [r0] 44 ldrh ip, [r0] 45 pack r5, r5, ip 46 47 ldrh ip, [r0] 48 ldrh lr, [r0] 49 pack ip, ip, lr 50 51 subs r2, r2, #8 52 stmia r1!, {r3 - r5, ip} 53 bpl .Linsw_8_lp 54 55 .Lno_insw_8: tst r2, #4 56 beq .Lno_insw_4 57 58 ldrh r3, [r0] 59 ldrh r4, [r0] 60 pack r3, r3, r4 61 62 ldrh r4, [r0] 63 ldrh ip, [r0] 64 pack r4, r4, ip 65 66 stmia r1!, {r3, r4} 67 68 .Lno_insw_4: movs r2, r2, lsl #31 69 bcc .Lno_insw_2 70 71 ldrh r3, [r0] 72 ldrh ip, [r0] 73 pack r3, r3, ip 74 str r3, [r1], #4 75 76 .Lno_insw_2: ldrhne r3, [r0] 77 strhne r3, [r1] 78 79 ldmfd sp!, {r4, r5, pc} 80 81 #ifdef __ARMEB__ 82 #define _BE_ONLY_(code...) code 83 #define _LE_ONLY_(code...) 84 #define push_hbyte0 lsr #8 85 #define pull_hbyte1 lsl #24 86 #else 87 #define _BE_ONLY_(code...) 88 #define _LE_ONLY_(code...) code 89 #define push_hbyte0 lsl #24 90 #define pull_hbyte1 lsr #8 91 #endif 92 93 .Linsw_noalign: stmfd sp!, {r4, lr} 94 ldrbcc ip, [r1, #-1]! 95 bcc 1f 96 97 ldrh ip, [r0] 98 sub r2, r2, #1 99 _BE_ONLY_( mov ip, ip, ror #8 ) 100 strb ip, [r1], #1 101 _LE_ONLY_( mov ip, ip, lsr #8 ) 102 _BE_ONLY_( mov ip, ip, lsr #24 ) 103 104 1: subs r2, r2, #2 105 bmi 3f 106 _BE_ONLY_( mov ip, ip, lsl #24 ) 107 108 2: ldrh r3, [r0] 109 ldrh r4, [r0] 110 subs r2, r2, #2 111 orr ip, ip, r3, lsl #8 112 orr ip, ip, r4, push_hbyte0 113 str ip, [r1], #4 114 mov ip, r4, pull_hbyte1 115 bpl 2b 116 117 _BE_ONLY_( mov ip, ip, lsr #24 ) 118 119 3: tst r2, #1 120 strb ip, [r1], #1 121 ldrhne ip, [r0] 122 _BE_ONLY_( movne ip, ip, ror #8 ) 123 strbne ip, [r1], #1 124 _LE_ONLY_( movne ip, ip, lsr #8 ) 125 _BE_ONLY_( movne ip, ip, lsr #24 ) 126 strbne ip, [r1] 127 ldmfd sp!, {r4, pc} 128 ENDPROC(__raw_readsw) 129