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-rw-r--r--arch/powerpc/boot/string.S265
1 files changed, 265 insertions, 0 deletions
diff --git a/arch/powerpc/boot/string.S b/arch/powerpc/boot/string.S
new file mode 100644
index 0000000000..d2a2dbf1ee
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+++ b/arch/powerpc/boot/string.S
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+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) Paul Mackerras 1997.
+ *
+ * NOTE: this code runs in 32 bit mode and is packaged as ELF32.
+ */
+
+#include "ppc_asm.h"
+
+ .text
+ .globl strcpy
+strcpy:
+ addi r5,r3,-1
+ addi r4,r4,-1
+1: lbzu r0,1(r4)
+ cmpwi 0,r0,0
+ stbu r0,1(r5)
+ bne 1b
+ blr
+
+ .globl strncpy
+strncpy:
+ cmpwi 0,r5,0
+ beqlr
+ mtctr r5
+ addi r6,r3,-1
+ addi r4,r4,-1
+1: lbzu r0,1(r4)
+ cmpwi 0,r0,0
+ stbu r0,1(r6)
+ bdnzf 2,1b /* dec ctr, branch if ctr != 0 && !cr0.eq */
+ blr
+
+ .globl strcat
+strcat:
+ addi r5,r3,-1
+ addi r4,r4,-1
+1: lbzu r0,1(r5)
+ cmpwi 0,r0,0
+ bne 1b
+ addi r5,r5,-1
+1: lbzu r0,1(r4)
+ cmpwi 0,r0,0
+ stbu r0,1(r5)
+ bne 1b
+ blr
+
+ .globl strchr
+strchr:
+ addi r3,r3,-1
+1: lbzu r0,1(r3)
+ cmpw 0,r0,r4
+ beqlr
+ cmpwi 0,r0,0
+ bne 1b
+ li r3,0
+ blr
+
+ .globl strcmp
+strcmp:
+ addi r5,r3,-1
+ addi r4,r4,-1
+1: lbzu r3,1(r5)
+ cmpwi 1,r3,0
+ lbzu r0,1(r4)
+ subf. r3,r0,r3
+ beqlr 1
+ beq 1b
+ blr
+
+ .globl strncmp
+strncmp:
+ mtctr r5
+ addi r5,r3,-1
+ addi r4,r4,-1
+1: lbzu r3,1(r5)
+ cmpwi 1,r3,0
+ lbzu r0,1(r4)
+ subf. r3,r0,r3
+ beqlr 1
+ bdnzt eq,1b
+ blr
+
+ .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 /* r7 = r5 >> 3 */
+ addi r6,r3,-4
+ addi r4,r4,-4
+ beq 3f /* if less than 8 bytes to do */
+ andi. r0,r6,3 /* get dest word aligned */
+ mtctr r7
+ bne 5f
+ andi. r0,r4,3 /* check src word aligned too */
+ bne 3f
+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
+ cmpw cr1,r0,r5
+ add r7,r0,r4
+ andi. r7,r7,3 /* will source be word-aligned too? */
+ ble cr1,3b
+ bne 3b /* do byte-by-byte if not */
+ 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 /* r7 = r5 >> 3 */
+ add r6,r3,r5
+ add r4,r4,r5
+ beq 3f
+ andi. r0,r6,3
+ mtctr r7
+ bne 5f
+ andi. r0,r4,3
+ bne 3f
+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: cmpw cr1,r0,r5
+ subf r7,r0,r4
+ andi. r7,r7,3
+ ble cr1,3b
+ bne 3b
+ 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 memchr
+memchr:
+ cmpwi 0,r5,0
+ blelr
+ mtctr r5
+ addi r3,r3,-1
+1: lbzu r0,1(r3)
+ cmpw r0,r4
+ beqlr
+ bdnz 1b
+ li r3,0
+ blr
+
+ .globl memcmp
+memcmp:
+ cmpwi 0,r5,0
+ ble 2f
+ 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
+2: li r3,0
+ blr
+
+
+/*
+ * Flush the dcache and invalidate the icache for a range of addresses.
+ *
+ * flush_cache(addr, len)
+ */
+ .global flush_cache
+flush_cache:
+ addi 4,4,0x1f /* len = (len + 0x1f) / 0x20 */
+ rlwinm. 4,4,27,5,31
+ mtctr 4
+ beqlr
+1: dcbf 0,3
+ icbi 0,3
+ addi 3,3,0x20
+ bdnz 1b
+ sync
+ isync
+ blr
+