arch/mips/loongson2ef/common/reset.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *
   4  * Copyright (C) 2007 Lemote, Inc. & Institute of Computing Technology
   5  * Author: Fuxin Zhang, zhangfx@lemote.com
   6  * Copyright (C) 2009 Lemote, Inc.
   7  * Author: Zhangjin Wu, wuzhangjin@gmail.com
   8  */
   9 #include <linux/init.h>
  10 #include <linux/pm.h>
  11
  12 #include <asm/idle.h>
  13 #include <asm/reboot.h>
  14
  15 #include <loongson.h>
  16
  17 static inline void loongson_reboot(void)
  18 {
  19 #ifndef CONFIG_CPU_JUMP_WORKAROUNDS
  20         ((void (*)(void))ioremap(LOONGSON_BOOT_BASE, 4)) ();
  21 #else
  22         void (*func)(void);
  23
  24         func = (void *)ioremap(LOONGSON_BOOT_BASE, 4);
  25
  26         __asm__ __volatile__(
  27         "       .set    noat                                            \n"
  28         "       jr      %[func]                                         \n"
  29         "       .set    at                                              \n"
  30         : /* No outputs */
  31         : [func] "r" (func));
  32 #endif
  33 }
  34
  35 static void loongson_restart(char *command)
  36 {
  37         /* do preparation for reboot */
  38         mach_prepare_reboot();
  39
  40         /* reboot via jumping to boot base address */
  41         loongson_reboot();
  42 }
  43
  44 static void loongson_poweroff(void)
  45 {
  46         mach_prepare_shutdown();
  47
  48         /*
  49          * It needs a wait loop here, but mips/kernel/reset.c already calls
  50          * a generic delay loop, machine_hang(), so simply return.
  51          */
  52         return;
  53 }
  54
  55 static void loongson_halt(void)
  56 {
  57         pr_notice("\n\n** You can safely turn off the power now **\n\n");
  58         while (1) {
  59                 if (cpu_wait)
  60                         cpu_wait();
  61         }
  62 }
  63
  64 static int __init mips_reboot_setup(void)
  65 {
  66         _machine_restart = loongson_restart;
  67         _machine_halt = loongson_halt;
  68         pm_power_off = loongson_poweroff;
  69
  70         return 0;
  71 }
  72
  73 arch_initcall(mips_reboot_setup);