arch/mips/vr41xx/common/pmu.c

   1 /*
   2  *  pmu.c, Power Management Unit routines for NEC VR4100 series.
   3  *
   4  *  Copyright (C) 2003-2005  Yoichi Yuasa <yuasa@hh.iij4u.or.jp>
   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/errno.h>
  21 #include <linux/init.h>
  22 #include <linux/ioport.h>
  23 #include <linux/kernel.h>
  24 #include <linux/smp.h>
  25 #include <linux/types.h>
  26
  27 #include <asm/cpu.h>
  28 #include <asm/io.h>
  29 #include <asm/reboot.h>
  30 #include <asm/system.h>
  31
  32 #define PMU_TYPE1_BASE  0x0b0000a0UL
  33 #define PMU_TYPE1_SIZE  0x0eUL
  34
  35 #define PMU_TYPE2_BASE  0x0f0000c0UL
  36 #define PMU_TYPE2_SIZE  0x10UL
  37
  38 #define PMUCNT2REG      0x06
  39  #define SOFTRST        0x0010
  40
  41 static void __iomem *pmu_base;
  42
  43 #define pmu_read(offset)                readw(pmu_base + (offset))
  44 #define pmu_write(offset, value)        writew((value), pmu_base + (offset))
  45
  46 static inline void software_reset(void)
  47 {
  48         uint16_t pmucnt2;
  49
  50         switch (current_cpu_data.cputype) {
  51         case CPU_VR4122:
  52         case CPU_VR4131:
  53         case CPU_VR4133:
  54                 pmucnt2 = pmu_read(PMUCNT2REG);
  55                 pmucnt2 |= SOFTRST;
  56                 pmu_write(PMUCNT2REG, pmucnt2);
  57                 break;
  58         default:
  59                 break;
  60         }
  61 }
  62
  63 static void vr41xx_restart(char *command)
  64 {
  65         local_irq_disable();
  66         software_reset();
  67         printk(KERN_NOTICE "\nYou can reset your system\n");
  68         while (1) ;
  69 }
  70
  71 static void vr41xx_halt(void)
  72 {
  73         local_irq_disable();
  74         printk(KERN_NOTICE "\nYou can turn off the power supply\n");
  75         while (1) ;
  76 }
  77
  78 static void vr41xx_power_off(void)
  79 {
  80         local_irq_disable();
  81         printk(KERN_NOTICE "\nYou can turn off the power supply\n");
  82         while (1) ;
  83 }
  84
  85 static int __init vr41xx_pmu_init(void)
  86 {
  87         unsigned long start, size;
  88
  89         switch (current_cpu_data.cputype) {
  90         case CPU_VR4111:
  91         case CPU_VR4121:
  92                 start = PMU_TYPE1_BASE;
  93                 size = PMU_TYPE1_SIZE;
  94                 break;
  95         case CPU_VR4122:
  96         case CPU_VR4131:
  97         case CPU_VR4133:
  98                 start = PMU_TYPE2_BASE;
  99                 size = PMU_TYPE2_SIZE;
 100                 break;
 101         default:
 102                 printk("Unexpected CPU of NEC VR4100 series\n");
 103                 return -ENODEV;
 104         }
 105
 106         if (request_mem_region(start, size, "PMU") == NULL)
 107                 return -EBUSY;
 108
 109         pmu_base = ioremap(start, size);
 110         if (pmu_base == NULL) {
 111                 release_mem_region(start, size);
 112                 return -EBUSY;
 113         }
 114
 115         _machine_restart = vr41xx_restart;
 116         _machine_halt = vr41xx_halt;
 117         _machine_power_off = vr41xx_power_off;
 118
 119         return 0;
 120 }
 121
 122 core_initcall(vr41xx_pmu_init);