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-rw-r--r--arch/arm/lib/copy_page.S46
1 files changed, 46 insertions, 0 deletions
diff --git a/arch/arm/lib/copy_page.S b/arch/arm/lib/copy_page.S
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+++ b/arch/arm/lib/copy_page.S
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+/*
+ * linux/arch/arm/lib/copypage.S
+ *
+ * Copyright (C) 1995-1999 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.
+ *
+ * ASM optimised string functions
+ */
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+#include <asm/constants.h>
+
+#define COPY_COUNT (PAGE_SZ/64 PLD( -1 ))
+
+ .text
+ .align 5
+/*
+ * StrongARM optimised copy_page routine
+ * now 1.78bytes/cycle, was 1.60 bytes/cycle (50MHz bus -> 89MB/s)
+ * Note that we probably achieve closer to the 100MB/s target with
+ * the core clock switching.
+ */
+ENTRY(copy_page)
+ stmfd sp!, {r4, lr} @ 2
+ PLD( pld [r1, #0] )
+ PLD( pld [r1, #32] )
+ mov r2, #COPY_COUNT @ 1
+ ldmia r1!, {r3, r4, ip, lr} @ 4+1
+1: PLD( pld [r1, #64] )
+ PLD( pld [r1, #96] )
+2: stmia r0!, {r3, r4, ip, lr} @ 4
+ ldmia r1!, {r3, r4, ip, lr} @ 4+1
+ stmia r0!, {r3, r4, ip, lr} @ 4
+ ldmia r1!, {r3, r4, ip, lr} @ 4+1
+ stmia r0!, {r3, r4, ip, lr} @ 4
+ ldmia r1!, {r3, r4, ip, lr} @ 4
+ subs r2, r2, #1 @ 1
+ stmia r0!, {r3, r4, ip, lr} @ 4
+ ldmgtia r1!, {r3, r4, ip, lr} @ 4
+ bgt 1b @ 1
+ PLD( ldmeqia r1!, {r3, r4, ip, lr} )
+ PLD( beq 2b )
+ LOADREGS(fd, sp!, {r4, pc}) @ 3