OpenCloudOS-Kernel/arch/powerpc/lib/code-patching.c

34 lines
917 B
C
Raw Normal View History

/*
* 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);
}