blob: 973d547ef01d5b1986f8bd6b14de97c8f9e17a6d [file] [log] [blame]
/*
* Copyright (C) 2001 Ben. Herrenschmidt (benh@kernel.crashing.org)
*
* Modifications for ppc64:
* Copyright (C) 2003 Dave Engebretsen <engebret@us.ibm.com>
*
* 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/cputable.h>
#include <asm/code-patching.h>
struct fixup_entry {
unsigned long mask;
unsigned long value;
long start_off;
long end_off;
long alt_start_off;
long alt_end_off;
};
static void patch_feature_section(unsigned long value, struct fixup_entry *fcur)
{
unsigned int *pstart, *pend, *p;
if ((value & fcur->mask) == fcur->value)
return;
pstart = ((unsigned int *)fcur) + (fcur->start_off / 4);
pend = ((unsigned int *)fcur) + (fcur->end_off / 4);
for (p = pstart; p < pend; p++) {
*p = PPC_NOP_INSTR;
asm volatile ("dcbst 0, %0" : : "r" (p));
}
asm volatile ("sync" : : : "memory");
for (p = pstart; p < pend; p++)
asm volatile ("icbi 0,%0" : : "r" (p));
asm volatile ("sync; isync" : : : "memory");
}
void do_feature_fixups(unsigned long value, void *fixup_start, void *fixup_end)
{
struct fixup_entry *fcur, *fend;
fcur = fixup_start;
fend = fixup_end;
for (; fcur < fend; fcur++)
patch_feature_section(value, fcur);
}