diff options
Diffstat (limited to 'arch/arm/lib/io-readsw-armv4.S')
-rw-r--r-- | arch/arm/lib/io-readsw-armv4.S | 130 |
1 files changed, 130 insertions, 0 deletions
diff --git a/arch/arm/lib/io-readsw-armv4.S b/arch/arm/lib/io-readsw-armv4.S new file mode 100644 index 00000000000..c92b66ecbe8 --- /dev/null +++ b/arch/arm/lib/io-readsw-armv4.S @@ -0,0 +1,130 @@ +/* + * linux/arch/arm/lib/io-readsw-armv4.S + * + * Copyright (C) 1995-2000 Russell King + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#include <linux/linkage.h> +#include <asm/assembler.h> + + .macro pack, rd, hw1, hw2 +#ifndef __ARMEB__ + orr \rd, \hw1, \hw2, lsl #16 +#else + orr \rd, \hw2, \hw1, lsl #16 +#endif + .endm + +.insw_align: movs ip, r1, lsl #31 + bne .insw_noalign + ldrh ip, [r0] + sub r2, r2, #1 + strh ip, [r1], #2 + +ENTRY(__raw_readsw) + teq r2, #0 + moveq pc, lr + tst r1, #3 + bne .insw_align + + stmfd sp!, {r4, r5, lr} + + subs r2, r2, #8 + bmi .no_insw_8 + +.insw_8_lp: ldrh r3, [r0] + ldrh r4, [r0] + pack r3, r3, r4 + + ldrh r4, [r0] + ldrh r5, [r0] + pack r4, r4, r5 + + ldrh r5, [r0] + ldrh ip, [r0] + pack r5, r5, ip + + ldrh ip, [r0] + ldrh lr, [r0] + pack ip, ip, lr + + subs r2, r2, #8 + stmia r1!, {r3 - r5, ip} + bpl .insw_8_lp + +.no_insw_8: tst r2, #4 + beq .no_insw_4 + + ldrh r3, [r0] + ldrh r4, [r0] + pack r3, r3, r4 + + ldrh r4, [r0] + ldrh ip, [r0] + pack r4, r4, ip + + stmia r1!, {r3, r4} + +.no_insw_4: movs r2, r2, lsl #31 + bcc .no_insw_2 + + ldrh r3, [r0] + ldrh ip, [r0] + pack r3, r3, ip + str r3, [r1], #4 + +.no_insw_2: ldrneh r3, [r0] + strneh r3, [r1] + + ldmfd sp!, {r4, r5, pc} + +#ifdef __ARMEB__ +#define _BE_ONLY_(code...) code +#define _LE_ONLY_(code...) +#define push_hbyte0 lsr #8 +#define pull_hbyte1 lsl #24 +#else +#define _BE_ONLY_(code...) +#define _LE_ONLY_(code...) code +#define push_hbyte0 lsl #24 +#define pull_hbyte1 lsr #8 +#endif + +.insw_noalign: stmfd sp!, {r4, lr} + ldrccb ip, [r1, #-1]! + bcc 1f + + ldrh ip, [r0] + sub r2, r2, #1 + _BE_ONLY_( mov ip, ip, ror #8 ) + strb ip, [r1], #1 + _LE_ONLY_( mov ip, ip, lsr #8 ) + _BE_ONLY_( mov ip, ip, lsr #24 ) + +1: subs r2, r2, #2 + bmi 3f + _BE_ONLY_( mov ip, ip, lsl #24 ) + +2: ldrh r3, [r0] + ldrh r4, [r0] + subs r2, r2, #2 + orr ip, ip, r3, lsl #8 + orr ip, ip, r4, push_hbyte0 + str ip, [r1], #4 + mov ip, r4, pull_hbyte1 + bpl 2b + + _BE_ONLY_( mov ip, ip, lsr #24 ) + +3: tst r2, #1 + strb ip, [r1], #1 + ldrneh ip, [r0] + _BE_ONLY_( movne ip, ip, ror #8 ) + strneb ip, [r1], #1 + _LE_ONLY_( movne ip, ip, lsr #8 ) + _BE_ONLY_( movne ip, ip, lsr #24 ) + strneb ip, [r1] + ldmfd sp!, {r4, pc} |