diff options
Diffstat (limited to 'kernel/arch/arm/lib/io-writesb.S')
-rw-r--r-- | kernel/arch/arm/lib/io-writesb.S | 94 |
1 files changed, 94 insertions, 0 deletions
diff --git a/kernel/arch/arm/lib/io-writesb.S b/kernel/arch/arm/lib/io-writesb.S new file mode 100644 index 000000000..a46bbc9b1 --- /dev/null +++ b/kernel/arch/arm/lib/io-writesb.S @@ -0,0 +1,94 @@ +/* + * linux/arch/arm/lib/io-writesb.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 outword, rd +#ifndef __ARMEB__ + strb \rd, [r0] + mov \rd, \rd, lsr #8 + strb \rd, [r0] + mov \rd, \rd, lsr #8 + strb \rd, [r0] + mov \rd, \rd, lsr #8 + strb \rd, [r0] +#else + mov lr, \rd, lsr #24 + strb lr, [r0] + mov lr, \rd, lsr #16 + strb lr, [r0] + mov lr, \rd, lsr #8 + strb lr, [r0] + strb \rd, [r0] +#endif + .endm + +.Loutsb_align: rsb ip, ip, #4 + cmp ip, r2 + movgt ip, r2 + cmp ip, #2 + ldrb r3, [r1], #1 + strb r3, [r0] + ldrgeb r3, [r1], #1 + strgeb r3, [r0] + ldrgtb r3, [r1], #1 + strgtb r3, [r0] + subs r2, r2, ip + bne .Loutsb_aligned + +ENTRY(__raw_writesb) + teq r2, #0 @ do we have to check for the zero len? + reteq lr + ands ip, r1, #3 + bne .Loutsb_align + +.Loutsb_aligned: + stmfd sp!, {r4, r5, lr} + + subs r2, r2, #16 + bmi .Loutsb_no_16 + +.Loutsb_16_lp: ldmia r1!, {r3, r4, r5, ip} + outword r3 + outword r4 + outword r5 + outword ip + subs r2, r2, #16 + bpl .Loutsb_16_lp + + tst r2, #15 + ldmeqfd sp!, {r4, r5, pc} + +.Loutsb_no_16: tst r2, #8 + beq .Loutsb_no_8 + + ldmia r1!, {r3, r4} + outword r3 + outword r4 + +.Loutsb_no_8: tst r2, #4 + beq .Loutsb_no_4 + + ldr r3, [r1], #4 + outword r3 + +.Loutsb_no_4: ands r2, r2, #3 + ldmeqfd sp!, {r4, r5, pc} + + cmp r2, #2 + ldrb r3, [r1], #1 + strb r3, [r0] + ldrgeb r3, [r1], #1 + strgeb r3, [r0] + ldrgtb r3, [r1] + strgtb r3, [r0] + + ldmfd sp!, {r4, r5, pc} +ENDPROC(__raw_writesb) |