powernv: Remove get/set_rtc_time when they are not present

Currently we continue to poll get/set_rtc_time even when we know they
are not working.

This changes it so that if it fails at boot time we remove the ppc_md
get/set_rtc_time hooks so that we don't end up polling known broken
calls.

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

1 files changed, 5 insertions, 1 deletions

diff --git a/arch/powerpc/platforms/powernv/opal-rtc.c b/arch/powerpc/platforms/powernv/opal-rtc.c
index 7d07c7e80ec0..b1885db8fdf3 100644
--- a/arch/powerpc/platforms/powernv/opal-rtc.c
+++ b/arch/powerpc/platforms/powernv/opal-rtc.c
@@ -18,6 +18,7 @@
 
 #include <asm/opal.h>
 #include <asm/firmware.h>
+#include <asm/machdep.h>
 
 static void opal_to_tm(u32 y_m_d, u64 h_m_s_ms, struct rtc_time *tm)
 {
@@ -48,8 +49,11 @@ unsigned long __init opal_get_boot_time(void)
                 else
                         mdelay(10);
         }
-        if (rc != OPAL_SUCCESS)
+        if (rc != OPAL_SUCCESS) {
+                ppc_md.get_rtc_time = NULL;
+                ppc_md.set_rtc_time = NULL;
                 return 0;
+        }
         y_m_d = be32_to_cpu(__y_m_d);
         h_m_s_ms = be64_to_cpu(__h_m_s_ms);
         opal_to_tm(y_m_d, h_m_s_ms, &tm);