1 /*
2 * pmu.c, Power Management Unit routines for NEC VR4100 series.
3 *
4 * Copyright (C) 2003-2007 Yoichi Yuasa <yuasa@linux-mips.org>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 */
20 #include <linux/cpu.h>
21 #include <linux/errno.h>
22 #include <linux/init.h>
23 #include <linux/ioport.h>
24 #include <linux/kernel.h>
25 #include <linux/pm.h>
26 #include <linux/sched.h>
27 #include <linux/types.h>
28
29 #include <asm/cacheflush.h>
30 #include <asm/cpu.h>
31 #include <asm/idle.h>
32 #include <asm/io.h>
33 #include <asm/processor.h>
34 #include <asm/reboot.h>
35
36 #define PMU_TYPE1_BASE 0x0b0000a0UL
37 #define PMU_TYPE1_SIZE 0x0eUL
38
39 #define PMU_TYPE2_BASE 0x0f0000c0UL
40 #define PMU_TYPE2_SIZE 0x10UL
41
42 #define PMUCNT2REG 0x06
43 #define SOFTRST 0x0010
44
45 static void __iomem *pmu_base;
46
47 #define pmu_read(offset) readw(pmu_base + (offset))
48 #define pmu_write(offset, value) writew((value), pmu_base + (offset))
49
vr41xx_cpu_wait(void)50 static void __cpuidle vr41xx_cpu_wait(void)
51 {
52 local_irq_disable();
53 if (!need_resched())
54 /*
55 * "standby" sets IE bit of the CP0_STATUS to 1.
56 */
57 __asm__("standby;\n");
58 else
59 local_irq_enable();
60 }
61
software_reset(void)62 static inline void software_reset(void)
63 {
64 uint16_t pmucnt2;
65
66 switch (current_cpu_type()) {
67 case CPU_VR4122:
68 case CPU_VR4131:
69 case CPU_VR4133:
70 pmucnt2 = pmu_read(PMUCNT2REG);
71 pmucnt2 |= SOFTRST;
72 pmu_write(PMUCNT2REG, pmucnt2);
73 break;
74 default:
75 set_c0_status(ST0_BEV | ST0_ERL);
76 change_c0_config(CONF_CM_CMASK, CONF_CM_UNCACHED);
77 __flush_cache_all();
78 write_c0_wired(0);
79 __asm__("jr %0"::"r"(0xbfc00000));
80 break;
81 }
82 }
83
vr41xx_restart(char * command)84 static void vr41xx_restart(char *command)
85 {
86 local_irq_disable();
87 software_reset();
88 while (1) ;
89 }
90
vr41xx_halt(void)91 static void vr41xx_halt(void)
92 {
93 local_irq_disable();
94 printk(KERN_NOTICE "\nYou can turn off the power supply\n");
95 __asm__("hibernate;\n");
96 }
97
vr41xx_pmu_init(void)98 static int __init vr41xx_pmu_init(void)
99 {
100 unsigned long start, size;
101
102 switch (current_cpu_type()) {
103 case CPU_VR4111:
104 case CPU_VR4121:
105 start = PMU_TYPE1_BASE;
106 size = PMU_TYPE1_SIZE;
107 break;
108 case CPU_VR4122:
109 case CPU_VR4131:
110 case CPU_VR4133:
111 start = PMU_TYPE2_BASE;
112 size = PMU_TYPE2_SIZE;
113 break;
114 default:
115 printk("Unexpected CPU of NEC VR4100 series\n");
116 return -ENODEV;
117 }
118
119 if (request_mem_region(start, size, "PMU") == NULL)
120 return -EBUSY;
121
122 pmu_base = ioremap(start, size);
123 if (pmu_base == NULL) {
124 release_mem_region(start, size);
125 return -EBUSY;
126 }
127
128 cpu_wait = vr41xx_cpu_wait;
129 _machine_restart = vr41xx_restart;
130 _machine_halt = vr41xx_halt;
131 pm_power_off = vr41xx_halt;
132
133 return 0;
134 }
135
136 core_initcall(vr41xx_pmu_init);
137
