[PATCH] ppc64: cleanup iseries runlight support

The iseries has a bar graph on the front panel that shows how busy it is.
The operating system sets and clears a bit in the CTRL register to control
it.

Instead of going to the complexity of using a thread info bit, just set and
clear it in the idle loop.

Also create two helper functions, ppc64_runlatch_on and ppc64_runlatch_off.

Finally don't use the short form of the SPR defines.

Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 3 insertions, 5 deletions

diff --git a/arch/ppc64/kernel/idle.c b/arch/ppc64/kernel/idle.c
index 6abc621d3ba..f24ce2b8720 100644
--- a/arch/ppc64/kernel/idle.c
+++ b/arch/ppc64/kernel/idle.c
@@ -75,13 +75,9 @@ static int iSeries_idle(void)
 {
 	struct paca_struct *lpaca;
 	long oldval;
-	unsigned long CTRL;
 
 	/* ensure iSeries run light will be out when idle */
-	clear_thread_flag(TIF_RUN_LIGHT);
-	CTRL = mfspr(CTRLF);
-	CTRL &= ~RUNLATCH;
-	mtspr(CTRLT, CTRL);
+	ppc64_runlatch_off();
 
 	lpaca = get_paca();
 
@@ -111,7 +107,9 @@ static int iSeries_idle(void)
 			}
 		}
 
+		ppc64_runlatch_on();
 		schedule();
+		ppc64_runlatch_off();
 	}
 
 	return 0;