1 files changed, 48 insertions, 0 deletions

diff --git a/arch/ppc64/boot/crt0.S b/arch/ppc64/boot/crt0.S
new file mode 100644
index 000000000000..04d3e74cd72f
--- /dev/null
+++ b/arch/ppc64/boot/crt0.S
@@ -0,0 +1,48 @@
+/*
+ * Copyright (C) Paul Mackerras 1997.
+ *
+ * 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.
+ *
+ * NOTE: this code runs in 32 bit mode and is packaged as ELF32.
+ */
+
+#include <asm/ppc_asm.h>
+
+        .text
+        .globl  _start
+_start:
+        lis     r9,_start@h
+        lis     r8,_etext@ha
+        addi    r8,r8,_etext@l
+1:      dcbf    r0,r9
+        icbi    r0,r9
+        addi    r9,r9,0x20
+        cmplwi  0,r9,8
+        blt     1b
+        sync
+        isync
+
+        ## Clear out the BSS as per ANSI C requirements
+
+        lis     r7,_end@ha
+        addi    r7,r7,_end@l            # r7 = &_end 
+        lis     r8,__bss_start@ha       # 
+        addi    r8,r8,__bss_start@l     # r8 = &_bss_start
+
+        ## Determine how large an area, in number of words, to clear
+
+        subf    r7,r8,r7                # r7 = &_end - &_bss_start + 1 
+        addi    r7,r7,3                 # r7 += 3 
+        srwi.   r7,r7,2                 # r7 = size in words.
+        beq     3f                      # If the size is zero, don't bother
+        addi    r8,r8,-4                # r8 -= 4 
+        mtctr   r7                      # SPRN_CTR = number of words to clear
+        li      r0,0                    # r0 = 0
+2:      stwu    r0,4(r8)                # Clear out a word
+        bdnz    2b                      # Keep clearing until done
+3:
+        b       start
+