Blame view

kernel/linux-rt-4.4.41/arch/powerpc/platforms/pasemi/idle.c 2.35 KB
5113f6f70   김현기   kernel add
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
  /*
   * Copyright (C) 2006-2007 PA Semi, Inc
   *
   * Maintained by: Olof Johansson <olof@lixom.net>
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License version 2 as
   * published by the Free Software Foundation.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program; if not, write to the Free Software
   * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
   *
   */
  
  #undef DEBUG
  
  #include <linux/kernel.h>
  #include <linux/string.h>
  #include <linux/irq.h>
  
  #include <asm/machdep.h>
  #include <asm/reg.h>
  #include <asm/smp.h>
  
  #include "pasemi.h"
  
  struct sleep_mode {
  	char *name;
  	void (*entry)(void);
  };
  
  static struct sleep_mode modes[] = {
  	{ .name = "spin", .entry = &idle_spin },
  	{ .name = "doze", .entry = &idle_doze },
  };
  
  static int current_mode = 0;
  
  static int pasemi_system_reset_exception(struct pt_regs *regs)
  {
  	/* If we were woken up from power savings, we need to return
  	 * to the calling function, since nip is not saved across
  	 * all modes.
  	 */
  
  	if (regs->msr & SRR1_WAKEMASK)
  		regs->nip = regs->link;
  
  	switch (regs->msr & SRR1_WAKEMASK) {
  	case SRR1_WAKEEE:
  		do_IRQ(regs);
  		break;
  	case SRR1_WAKEDEC:
  		timer_interrupt(regs);
  		break;
  	default:
  		/* do system reset */
  		return 0;
  	}
  
  	/* Set higher astate since we come out of power savings at 0 */
  	restore_astate(hard_smp_processor_id());
  
  	/* everything handled */
  	regs->msr |= MSR_RI;
  	return 1;
  }
  
  static int __init pasemi_idle_init(void)
  {
  #ifndef CONFIG_PPC_PASEMI_CPUFREQ
  	printk(KERN_WARNING "No cpufreq driver, powersavings modes disabled
  ");
  	current_mode = 0;
  #endif
  
  	ppc_md.system_reset_exception = pasemi_system_reset_exception;
  	ppc_md.power_save = modes[current_mode].entry;
  	printk(KERN_INFO "Using PA6T idle loop (%s)
  ", modes[current_mode].name);
  
  	return 0;
  }
  machine_late_initcall(pasemi, pasemi_idle_init);
  
  static int __init idle_param(char *p)
  {
  	int i;
  	for (i = 0; i < ARRAY_SIZE(modes); i++) {
  		if (!strcmp(modes[i].name, p)) {
  			current_mode = i;
  			break;
  		}
  	}
  	return 0;
  }
  
  early_param("idle", idle_param);