powerpc: Add PPC_NOP_INSTR, a hash define for the preferred nop instruction

A bunch of code has hard-coded the value for a "nop" instruction, it
would be nice to have a #define for it.

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>

4 files changed, 7 insertions, 3 deletions

diff --git a/arch/powerpc/kernel/cputable.c b/arch/powerpc/kernel/cputable.c
index f8deb3761de4..ba5b23f54764 100644
--- a/arch/powerpc/kernel/cputable.c
+++ b/arch/powerpc/kernel/cputable.c
@@ -17,6 +17,7 @@
 #include <linux/module.h>
 
 #include <asm/oprofile_impl.h>
+#include <asm/code-patching.h>
 #include <asm/cputable.h>
 #include <asm/prom.h>           /* for PTRRELOC on ARCH=ppc */
 
@@ -1663,7 +1664,7 @@ void do_feature_fixups(unsigned long value, void *fixup_start, void *fixup_end)
                 pend = ((unsigned int *)fcur) + (fcur->end_off / 4);
 
                 for (p = pstart; p < pend; p++) {
-                        *p = 0x60000000u;
+                        *p = PPC_NOP_INSTR;
                         asm volatile ("dcbst 0, %0" : : "r" (p));
                 }
                 asm volatile ("sync" : : : "memory");
diff --git a/arch/powerpc/kernel/crash_dump.c b/arch/powerpc/kernel/crash_dump.c
index 26648544d5e4..e0debcca0bfa 100644
--- a/arch/powerpc/kernel/crash_dump.c
+++ b/arch/powerpc/kernel/crash_dump.c
@@ -44,7 +44,7 @@ static void __init create_trampoline(unsigned long addr)
          * branch to "addr" we jump to ("addr" + 32 MB). Although it requires
          * two instructions it doesn't require any registers.
          */
-        patch_instruction(p, 0x60000000); /* nop */
+        patch_instruction(p, PPC_NOP_INSTR);
         patch_branch(++p, addr + PHYSICAL_START, 0);
 }
 
diff --git a/arch/powerpc/kernel/module_64.c b/arch/powerpc/kernel/module_64.c
index 4803f2de98dd..ee6a2982d567 100644
--- a/arch/powerpc/kernel/module_64.c
+++ b/arch/powerpc/kernel/module_64.c
@@ -24,6 +24,7 @@
 #include <asm/module.h>
 #include <asm/uaccess.h>
 #include <asm/firmware.h>
+#include <asm/code-patching.h>
 #include <linux/sort.h>
 
 #include "setup.h"
@@ -330,7 +331,7 @@ static unsigned long stub_for_addr(Elf64_Shdr *sechdrs,
    restore r2. */
 static int restore_r2(u32 *instruction, struct module *me)
 {
-        if (*instruction != 0x60000000) {
+        if (*instruction != PPC_NOP_INSTR) {
                 printk("%s: Expect noop after relocate, got %08x\n",
                        me->name, *instruction);
                 return 0;
diff --git a/include/asm-powerpc/code-patching.h b/include/asm-powerpc/code-patching.h
index 40ad46b1dd9d..ef3a5d156dba 100644
--- a/include/asm-powerpc/code-patching.h
+++ b/include/asm-powerpc/code-patching.h
@@ -12,6 +12,8 @@
 
 #include <asm/types.h>
 
+#define PPC_NOP_INSTR   0x60000000
+
 /* Flags for create_branch:
  * "b"   == create_branch(addr, target, 0);
  * "ba"  == create_branch(addr, target, BRANCH_ABSOLUTE);