Paul Mundt | 1da1180 | 2008-11-26 15:52:44 +0900 | [diff] [blame] | 1 | /* |
| 2 | * The idle loop for all SuperH platforms. |
| 3 | * |
| 4 | * Copyright (C) 2002 - 2008 Paul Mundt |
| 5 | * |
| 6 | * This file is subject to the terms and conditions of the GNU General Public |
| 7 | * License. See the file "COPYING" in the main directory of this archive |
| 8 | * for more details. |
| 9 | */ |
| 10 | #include <linux/module.h> |
| 11 | #include <linux/init.h> |
| 12 | #include <linux/mm.h> |
| 13 | #include <linux/pm.h> |
| 14 | #include <linux/tick.h> |
| 15 | #include <linux/preempt.h> |
| 16 | #include <linux/thread_info.h> |
| 17 | #include <linux/irqflags.h> |
| 18 | #include <asm/pgalloc.h> |
| 19 | #include <asm/system.h> |
| 20 | #include <asm/atomic.h> |
| 21 | |
| 22 | static int hlt_counter; |
| 23 | void (*pm_idle)(void); |
| 24 | void (*pm_power_off)(void); |
| 25 | EXPORT_SYMBOL(pm_power_off); |
| 26 | |
| 27 | static int __init nohlt_setup(char *__unused) |
| 28 | { |
| 29 | hlt_counter = 1; |
| 30 | return 1; |
| 31 | } |
| 32 | __setup("nohlt", nohlt_setup); |
| 33 | |
| 34 | static int __init hlt_setup(char *__unused) |
| 35 | { |
| 36 | hlt_counter = 0; |
| 37 | return 1; |
| 38 | } |
| 39 | __setup("hlt", hlt_setup); |
| 40 | |
| 41 | static void default_idle(void) |
| 42 | { |
| 43 | if (!hlt_counter) { |
| 44 | clear_thread_flag(TIF_POLLING_NRFLAG); |
| 45 | smp_mb__after_clear_bit(); |
| 46 | set_bl_bit(); |
| 47 | stop_critical_timings(); |
| 48 | |
| 49 | while (!need_resched()) |
| 50 | cpu_sleep(); |
| 51 | |
| 52 | start_critical_timings(); |
| 53 | clear_bl_bit(); |
| 54 | set_thread_flag(TIF_POLLING_NRFLAG); |
| 55 | } else |
| 56 | while (!need_resched()) |
| 57 | cpu_relax(); |
| 58 | } |
| 59 | |
| 60 | void cpu_idle(void) |
| 61 | { |
| 62 | set_thread_flag(TIF_POLLING_NRFLAG); |
| 63 | |
| 64 | /* endless idle loop with no priority at all */ |
| 65 | while (1) { |
| 66 | void (*idle)(void) = pm_idle; |
| 67 | |
| 68 | if (!idle) |
| 69 | idle = default_idle; |
| 70 | |
| 71 | tick_nohz_stop_sched_tick(1); |
| 72 | while (!need_resched()) |
| 73 | idle(); |
| 74 | tick_nohz_restart_sched_tick(); |
| 75 | |
| 76 | preempt_enable_no_resched(); |
| 77 | schedule(); |
| 78 | preempt_disable(); |
| 79 | check_pgt_cache(); |
| 80 | } |
| 81 | } |