Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * Idle daemon for PowerPC. Idle daemon will handle any action | |
3 | * that needs to be taken when the system becomes idle. | |
4 | * | |
5 | * Originally Written by Cort Dougan (cort@cs.nmt.edu) | |
6 | * | |
7 | * iSeries supported added by Mike Corrigan <mikejc@us.ibm.com> | |
8 | * | |
9 | * Additional shared processor, SMT, and firmware support | |
10 | * Copyright (c) 2003 Dave Engebretsen <engebret@us.ibm.com> | |
11 | * | |
12 | * This program is free software; you can redistribute it and/or | |
13 | * modify it under the terms of the GNU General Public License | |
14 | * as published by the Free Software Foundation; either version | |
15 | * 2 of the License, or (at your option) any later version. | |
16 | */ | |
17 | ||
18 | #include <linux/config.h> | |
19 | #include <linux/sched.h> | |
20 | #include <linux/kernel.h> | |
21 | #include <linux/smp.h> | |
22 | #include <linux/cpu.h> | |
23 | #include <linux/module.h> | |
24 | #include <linux/sysctl.h> | |
25 | #include <linux/smp.h> | |
26 | ||
27 | #include <asm/system.h> | |
28 | #include <asm/processor.h> | |
29 | #include <asm/mmu.h> | |
30 | #include <asm/cputable.h> | |
31 | #include <asm/time.h> | |
32 | #include <asm/iSeries/HvCall.h> | |
33 | #include <asm/iSeries/ItLpQueue.h> | |
34 | #include <asm/plpar_wrappers.h> | |
35 | #include <asm/systemcfg.h> | |
fd899c0c | 36 | #include <asm/machdep.h> |
1da177e4 LT |
37 | |
38 | extern void power4_idle(void); | |
39 | ||
fd899c0c | 40 | int default_idle(void) |
1da177e4 LT |
41 | { |
42 | long oldval; | |
43 | unsigned int cpu = smp_processor_id(); | |
44 | ||
45 | while (1) { | |
46 | oldval = test_and_clear_thread_flag(TIF_NEED_RESCHED); | |
47 | ||
48 | if (!oldval) { | |
49 | set_thread_flag(TIF_POLLING_NRFLAG); | |
50 | ||
51 | while (!need_resched() && !cpu_is_offline(cpu)) { | |
52 | barrier(); | |
53 | /* | |
54 | * Go into low thread priority and possibly | |
55 | * low power mode. | |
56 | */ | |
57 | HMT_low(); | |
58 | HMT_very_low(); | |
59 | } | |
60 | ||
61 | HMT_medium(); | |
62 | clear_thread_flag(TIF_POLLING_NRFLAG); | |
63 | } else { | |
64 | set_need_resched(); | |
65 | } | |
66 | ||
67 | schedule(); | |
68 | if (cpu_is_offline(cpu) && system_state == SYSTEM_RUNNING) | |
69 | cpu_die(); | |
70 | } | |
71 | ||
72 | return 0; | |
73 | } | |
74 | ||
fd899c0c | 75 | int native_idle(void) |
1da177e4 LT |
76 | { |
77 | while(1) { | |
78 | /* check CPU type here */ | |
79 | if (!need_resched()) | |
80 | power4_idle(); | |
81 | if (need_resched()) | |
82 | schedule(); | |
83 | ||
39c715b7 | 84 | if (cpu_is_offline(raw_smp_processor_id()) && |
1da177e4 LT |
85 | system_state == SYSTEM_RUNNING) |
86 | cpu_die(); | |
87 | } | |
88 | return 0; | |
89 | } | |
90 | ||
1da177e4 LT |
91 | void cpu_idle(void) |
92 | { | |
fd899c0c ME |
93 | BUG_ON(NULL == ppc_md.idle_loop); |
94 | ppc_md.idle_loop(); | |
1da177e4 LT |
95 | } |
96 | ||
97 | int powersave_nap; | |
98 | ||
99 | #ifdef CONFIG_SYSCTL | |
100 | /* | |
101 | * Register the sysctl to set/clear powersave_nap. | |
102 | */ | |
103 | static ctl_table powersave_nap_ctl_table[]={ | |
104 | { | |
105 | .ctl_name = KERN_PPC_POWERSAVE_NAP, | |
106 | .procname = "powersave-nap", | |
107 | .data = &powersave_nap, | |
108 | .maxlen = sizeof(int), | |
109 | .mode = 0644, | |
110 | .proc_handler = &proc_dointvec, | |
111 | }, | |
112 | { 0, }, | |
113 | }; | |
114 | static ctl_table powersave_nap_sysctl_root[] = { | |
115 | { 1, "kernel", NULL, 0, 0755, powersave_nap_ctl_table, }, | |
116 | { 0,}, | |
117 | }; | |
118 | ||
119 | static int __init | |
120 | register_powersave_nap_sysctl(void) | |
121 | { | |
122 | register_sysctl_table(powersave_nap_sysctl_root, 0); | |
123 | ||
124 | return 0; | |
125 | } | |
126 | __initcall(register_powersave_nap_sysctl); | |
127 | #endif |