openrisc: Use generic idle loop

Idle poller with an extra check_pgt_cache() invocation. Use the core
code.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Cc: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Magnus Damm <magnus.damm@gmail.com>
Link: http://lkml.kernel.org/r/20130321215234.886530981@linutronix.deSigned-off-by: Thomas Gleixner <tglx@linutronix.de>

arch/openrisc/Kconfig

@@ -21,6 +21,7 @@ config OPENRISC
 	select GENERIC_CLOCKEVENTS
 	select GENERIC_STRNCPY_FROM_USER
 	select GENERIC_STRNLEN_USER
+	select GENERIC_IDLE_LOOP
 	select MODULES_USE_ELF_RELA
 
 config MMU

arch/openrisc/kernel/Makefile

@@ -4,7 +4,7 @@
 
 extra-y	:= head.o vmlinux.lds
 
-obj-y	:= setup.o idle.o or32_ksyms.o process.o dma.o \
+obj-y	:= setup.o or32_ksyms.o process.o dma.o \
 	   traps.o time.o irq.o entry.o ptrace.o signal.o \
 	   sys_call_table.o
 

arch/openrisc/kernel/idle.c

-/*
- * OpenRISC idle.c
- *
- * Linux architectural port borrowing liberally from similar works of
- * others.  All original copyrights apply as per the original source
- * declaration.
- *
- * Modifications for the OpenRISC architecture:
- * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
- * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
- *
- *      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.
- *
- * Idle daemon for or32.  Idle daemon will handle any action
- * that needs to be taken when the system becomes idle.
- */
-
-#include <linux/errno.h>
-#include <linux/sched.h>
-#include <linux/kernel.h>
-#include <linux/mm.h>
-#include <linux/smp.h>
-#include <linux/stddef.h>
-#include <linux/unistd.h>
-#include <linux/ptrace.h>
-#include <linux/slab.h>
-#include <linux/tick.h>
-
-#include <asm/pgtable.h>
-#include <asm/uaccess.h>
-#include <asm/io.h>
-#include <asm/processor.h>
-#include <asm/mmu.h>
-#include <asm/cache.h>
-#include <asm/pgalloc.h>
-
-void (*powersave) (void) = NULL;
-
-void cpu_idle(void)
-{
-	set_thread_flag(TIF_POLLING_NRFLAG);
-
-	/* endless idle loop with no priority at all */
-	while (1) {
-		tick_nohz_idle_enter();
-		rcu_idle_enter();
-
-		while (!need_resched()) {
-			check_pgt_cache();
-			rmb();
-
-			clear_thread_flag(TIF_POLLING_NRFLAG);
-
-			local_irq_disable();
-			/* Don't trace irqs off for idle */
-			stop_critical_timings();
-			if (!need_resched() && powersave != NULL)
-				powersave();
-			start_critical_timings();
-			local_irq_enable();
-			set_thread_flag(TIF_POLLING_NRFLAG);
-		}
-
-		rcu_idle_exit();
-		tick_nohz_idle_exit();
-		preempt_enable_no_resched();
-		schedule();
-		preempt_disable();
-	}
-}