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-rw-r--r--arch/ppc/boot/common/string.S150
1 files changed, 150 insertions, 0 deletions
diff --git a/arch/ppc/boot/common/string.S b/arch/ppc/boot/common/string.S
new file mode 100644
index 000000000000..8016e43c4771
--- /dev/null
+++ b/arch/ppc/boot/common/string.S
@@ -0,0 +1,150 @@
+/*
+ * String handling functions for PowerPC.
+ *
+ * Copyright (C) 1996 Paul Mackerras.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+#define r0 0
+#define r3 3
+#define r4 4
+#define r5 5
+#define r6 6
+#define r7 7
+#define r8 8
+
+ .globl strlen
+strlen:
+ addi r4,r3,-1
+1: lbzu r0,1(r4)
+ cmpwi 0,r0,0
+ bne 1b
+ subf r3,r3,r4
+ blr
+
+ .globl memset
+memset:
+ rlwimi r4,r4,8,16,23
+ rlwimi r4,r4,16,0,15
+ addi r6,r3,-4
+ cmplwi 0,r5,4
+ blt 7f
+ stwu r4,4(r6)
+ beqlr
+ andi. r0,r6,3
+ add r5,r0,r5
+ subf r6,r0,r6
+ rlwinm r0,r5,32-2,2,31
+ mtctr r0
+ bdz 6f
+1: stwu r4,4(r6)
+ bdnz 1b
+6: andi. r5,r5,3
+7: cmpwi 0,r5,0
+ beqlr
+ mtctr r5
+ addi r6,r6,3
+8: stbu r4,1(r6)
+ bdnz 8b
+ blr
+
+ .globl memmove
+memmove:
+ cmplw 0,r3,r4
+ bgt backwards_memcpy
+ /* fall through */
+
+ .globl memcpy
+memcpy:
+ rlwinm. r7,r5,32-3,3,31 /* r0 = r5 >> 3 */
+ addi r6,r3,-4
+ addi r4,r4,-4
+ beq 2f /* if less than 8 bytes to do */
+ andi. r0,r6,3 /* get dest word aligned */
+ mtctr r7
+ bne 5f
+1: lwz r7,4(r4)
+ lwzu r8,8(r4)
+ stw r7,4(r6)
+ stwu r8,8(r6)
+ bdnz 1b
+ andi. r5,r5,7
+2: cmplwi 0,r5,4
+ blt 3f
+ lwzu r0,4(r4)
+ addi r5,r5,-4
+ stwu r0,4(r6)
+3: cmpwi 0,r5,0
+ beqlr
+ mtctr r5
+ addi r4,r4,3
+ addi r6,r6,3
+4: lbzu r0,1(r4)
+ stbu r0,1(r6)
+ bdnz 4b
+ blr
+5: subfic r0,r0,4
+ mtctr r0
+6: lbz r7,4(r4)
+ addi r4,r4,1
+ stb r7,4(r6)
+ addi r6,r6,1
+ bdnz 6b
+ subf r5,r0,r5
+ rlwinm. r7,r5,32-3,3,31
+ beq 2b
+ mtctr r7
+ b 1b
+
+ .globl backwards_memcpy
+backwards_memcpy:
+ rlwinm. r7,r5,32-3,3,31 /* r0 = r5 >> 3 */
+ add r6,r3,r5
+ add r4,r4,r5
+ beq 2f
+ andi. r0,r6,3
+ mtctr r7
+ bne 5f
+1: lwz r7,-4(r4)
+ lwzu r8,-8(r4)
+ stw r7,-4(r6)
+ stwu r8,-8(r6)
+ bdnz 1b
+ andi. r5,r5,7
+2: cmplwi 0,r5,4
+ blt 3f
+ lwzu r0,-4(r4)
+ subi r5,r5,4
+ stwu r0,-4(r6)
+3: cmpwi 0,r5,0
+ beqlr
+ mtctr r5
+4: lbzu r0,-1(r4)
+ stbu r0,-1(r6)
+ bdnz 4b
+ blr
+5: mtctr r0
+6: lbzu r7,-1(r4)
+ stbu r7,-1(r6)
+ bdnz 6b
+ subf r5,r0,r5
+ rlwinm. r7,r5,32-3,3,31
+ beq 2b
+ mtctr r7
+ b 1b
+
+ .globl memcmp
+memcmp:
+ cmpwi 0,r5,0
+ blelr
+ mtctr r5
+ addi r6,r3,-1
+ addi r4,r4,-1
+1: lbzu r3,1(r6)
+ lbzu r0,1(r4)
+ subf. r3,r0,r3
+ bdnzt 2,1b
+ blr