arch/mips/pic32/common/reset.c

   1 /*
   2  * Joshua Henderson <joshua.henderson@microchip.com>
   3  * Copyright (C) 2015 Microchip Technology Inc.  All rights reserved.
   4  *
   5  *  This program is free software; you can distribute it and/or modify it
   6  *  under the terms of the GNU General Public License (Version 2) as
   7  *  published by the Free Software Foundation.
   8  *
   9  *  This program is distributed in the hope it will be useful, but WITHOUT
  10  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  *  for more details.
  13  */
  14 #include <linux/init.h>
  15 #include <linux/pm.h>
  16 #include <asm/reboot.h>
  17 #include <asm/mach-pic32/pic32.h>
  18
  19 #define PIC32_RSWRST            0x10
  20
  21 static void pic32_halt(void)
  22 {
  23         while (1) {
  24                 __asm__(".set push;\n"
  25                         ".set arch=r4000;\n"
  26                         "wait;\n"
  27                         ".set pop;\n"
  28                 );
  29         }
  30 }
  31
  32 static void pic32_machine_restart(char *command)
  33 {
  34         void __iomem *reg =
  35                 ioremap(PIC32_BASE_RESET + PIC32_RSWRST, sizeof(u32));
  36
  37         pic32_syskey_unlock();
  38
  39         /* magic write/read */
  40         __raw_writel(1, reg);
  41         (void)__raw_readl(reg);
  42
  43         pic32_halt();
  44 }
  45
  46 static void pic32_machine_halt(void)
  47 {
  48         local_irq_disable();
  49
  50         pic32_halt();
  51 }
  52
  53 static int __init mips_reboot_setup(void)
  54 {
  55         _machine_restart = pic32_machine_restart;
  56         _machine_halt = pic32_machine_halt;
  57         pm_power_off = pic32_machine_halt;
  58
  59         return 0;
  60 }
  61
  62 arch_initcall(mips_reboot_setup);