2 files changed, 57 insertions, 0 deletions

diff --git a/arch/powerpc/lib/Makefile b/arch/powerpc/lib/Makefile
index e7f7042b9f61..fc52771f0cdb 100644
--- a/arch/powerpc/lib/Makefile
+++ b/arch/powerpc/lib/Makefile
@@ -26,3 +26,4 @@ endif
 obj-$(CONFIG_PPC_LIB_RHEAP) += rheap.o
 
 obj-y                   += code-patching.o
+obj-y                   += feature-fixups.o
diff --git a/arch/powerpc/lib/feature-fixups.c b/arch/powerpc/lib/feature-fixups.c
new file mode 100644
index 000000000000..f6fd5d2ff10d
--- /dev/null
+++ b/arch/powerpc/lib/feature-fixups.c
@@ -0,0 +1,56 @@
+/*
+ *  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;
+};
+
+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);
+}