powerpc: Move code patching code into arch/powerpc/lib/code-patching.c

We currently have a few routines for patching code in asm/system.h, because
they didn't fit anywhere else. I'd like to clean them up a little and add
some more, so first move them into a dedicated C file - they don't need to
be inlined.

While we're moving the code, drop create_function_call(), it's intended
caller never got merged and will be replaced in future with something
different.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

arch/powerpc/lib/Makefile

@@ -24,3 +24,5 @@ obj-$(CONFIG_SMP)	+= locks.o
 endif
 
 obj-$(CONFIG_PPC_LIB_RHEAP) += rheap.o
+
+obj-y			+= code-patching.o

arch/powerpc/lib/code-patching.c

@@ -0,0 +1,33 @@
+/*
+ *  Copyright 2008 Michael Ellerman, IBM Corporation.
+ *
+ *  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.
+ */
+
+#include <linux/kernel.h>
+#include <asm/code-patching.h>
+
+
+void create_instruction(unsigned long addr, unsigned int instr)
+{
+	unsigned int *p;
+	p  = (unsigned int *)addr;
+	*p = instr;
+	asm ("dcbst 0, %0; sync; icbi 0,%0; sync; isync" : : "r" (p));
+}
+
+void create_branch(unsigned long addr, unsigned long target, int flags)
+{
+	unsigned int instruction;
+
+	if (! (flags & BRANCH_ABSOLUTE))
+		target = target - addr;
+
+	/* Mask out the flags and target, so they don't step on each other. */
+	instruction = 0x48000000 | (flags & 0x3) | (target & 0x03FFFFFC);
+
+	create_instruction(addr, instruction);
+}