1 files changed, 80 insertions, 0 deletions

diff --git a/arch/arm/lib/memset.S b/arch/arm/lib/memset.S
new file mode 100644
index 000000000000..a1795f599937
--- /dev/null
+++ b/arch/arm/lib/memset.S
@@ -0,0 +1,80 @@
+/*
+ *  linux/arch/arm/lib/memset.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.
+ *
+ *  ASM optimised string functions
+ */
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+
+        .text
+        .align  5
+        .word   0
+
+1:      subs    r2, r2, #4              @ 1 do we have enough
+        blt     5f                      @ 1 bytes to align with?
+        cmp     r3, #2                  @ 1
+        strltb  r1, [r0], #1            @ 1
+        strleb  r1, [r0], #1            @ 1
+        strb    r1, [r0], #1            @ 1
+        add     r2, r2, r3              @ 1 (r2 = r2 - (4 - r3))
+/*
+ * The pointer is now aligned and the length is adjusted.  Try doing the
+ * memzero again.
+ */
+
+ENTRY(memset)
+        ands    r3, r0, #3              @ 1 unaligned?
+        bne     1b                      @ 1
+/*
+ * we know that the pointer in r0 is aligned to a word boundary.
+ */
+        orr     r1, r1, r1, lsl #8
+        orr     r1, r1, r1, lsl #16
+        mov     r3, r1
+        cmp     r2, #16
+        blt     4f
+/*
+ * We need an extra register for this loop - save the return address and
+ * use the LR
+ */
+        str     lr, [sp, #-4]!
+        mov     ip, r1
+        mov     lr, r1
+
+2:      subs    r2, r2, #64
+        stmgeia r0!, {r1, r3, ip, lr}   @ 64 bytes at a time.
+        stmgeia r0!, {r1, r3, ip, lr}
+        stmgeia r0!, {r1, r3, ip, lr}
+        stmgeia r0!, {r1, r3, ip, lr}
+        bgt     2b
+        LOADREGS(eqfd, sp!, {pc})       @ Now <64 bytes to go.
+/*
+ * No need to correct the count; we're only testing bits from now on
+ */
+        tst     r2, #32
+        stmneia r0!, {r1, r3, ip, lr}
+        stmneia r0!, {r1, r3, ip, lr}
+        tst     r2, #16
+        stmneia r0!, {r1, r3, ip, lr}
+        ldr     lr, [sp], #4
+
+4:      tst     r2, #8
+        stmneia r0!, {r1, r3}
+        tst     r2, #4
+        strne   r1, [r0], #4
+/*
+ * When we get here, we've got less than 4 bytes to zero.  We
+ * may have an unaligned pointer as well.
+ */
+5:      tst     r2, #2
+        strneb  r1, [r0], #1
+        strneb  r1, [r0], #1
+        tst     r2, #1
+        strneb  r1, [r0], #1
+        RETINSTR(mov,pc,lr)