[POWERPC] Only call ppc_md.setup_arch() if it is provided

This allows platforms which don't have anything to do at setup_arch time
(like a bunch of the 4xx platforms) to eliminate an empty setup_arch hook.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Paul Mackerras <paulus@samba.org>

3 files changed, 5 insertions, 3 deletions

diff --git a/arch/powerpc/kernel/setup_32.c b/arch/powerpc/kernel/setup_32.c
index 7474502dace5..cd870a823d18 100644
--- a/arch/powerpc/kernel/setup_32.c
+++ b/arch/powerpc/kernel/setup_32.c
@@ -290,7 +290,8 @@ void __init setup_arch(char **cmdline_p)
         conswitchp = &dummy_con;
 #endif
 
-        ppc_md.setup_arch();
+        if (ppc_md.setup_arch)
+                ppc_md.setup_arch();
         if ( ppc_md.progress ) ppc_md.progress("arch: exit", 0x3eab);
 
         paging_init();
diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c
index 3089eaed3256..008ab6823b02 100644
--- a/arch/powerpc/kernel/setup_64.c
+++ b/arch/powerpc/kernel/setup_64.c
@@ -530,7 +530,8 @@ void __init setup_arch(char **cmdline_p)
         conswitchp = &dummy_con;
 #endif
 
-        ppc_md.setup_arch();
+        if (ppc_md.setup_arch)
+                ppc_md.setup_arch();
 
         paging_init();
         ppc64_boot_msg(0x15, "Setup Done");
diff --git a/include/asm-powerpc/machdep.h b/include/asm-powerpc/machdep.h
index 71c6e7eb2a26..cc7c17f16a9a 100644
--- a/include/asm-powerpc/machdep.h
+++ b/include/asm-powerpc/machdep.h
@@ -99,7 +99,7 @@ struct machdep_calls {
 #endif /* CONFIG_PPC64 */
 
         int             (*probe)(void);
-        void            (*setup_arch)(void);
+        void            (*setup_arch)(void); /* Optional, may be NULL */
         void            (*init_early)(void);
         /* Optional, may be NULL. */
         void            (*show_cpuinfo)(struct seq_file *m);