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-rw-r--r--arch/arm/lib/io-writesb.S92
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diff --git a/arch/arm/lib/io-writesb.S b/arch/arm/lib/io-writesb.S
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+/*
+ * 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
+
+.outsb_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 .outsb_aligned
+
+ENTRY(__raw_writesb)
+ teq r2, #0 @ do we have to check for the zero len?
+ moveq pc, lr
+ ands ip, r1, #3
+ bne .outsb_align
+
+.outsb_aligned: stmfd sp!, {r4, r5, lr}
+
+ subs r2, r2, #16
+ bmi .outsb_no_16
+
+.outsb_16_lp: ldmia r1!, {r3, r4, r5, ip}
+ outword r3
+ outword r4
+ outword r5
+ outword ip
+ subs r2, r2, #16
+ bpl .outsb_16_lp
+
+ tst r2, #15
+ LOADREGS(eqfd, sp!, {r4, r5, pc})
+
+.outsb_no_16: tst r2, #8
+ beq .outsb_no_8
+
+ ldmia r1!, {r3, r4}
+ outword r3
+ outword r4
+
+.outsb_no_8: tst r2, #4
+ beq .outsb_no_4
+
+ ldr r3, [r1], #4
+ outword r3
+
+.outsb_no_4: ands r2, r2, #3
+ LOADREGS(eqfd, 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]
+
+ LOADREGS(fd, sp!, {r4, r5, pc})