arch/arm/mach-tegra/hotplug.c

   1 /*
   2  *
   3  *  Copyright (C) 2002 ARM Ltd.
   4  *  All Rights Reserved
   5  *  Copyright (c) 2010, 2012 NVIDIA Corporation. All rights reserved.
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11 #include <linux/kernel.h>
  12 #include <linux/smp.h>
  13
  14 #include <asm/cacheflush.h>
  15 #include <asm/smp_plat.h>
  16
  17 #include "sleep.h"
  18 #include "tegra_cpu_car.h"
  19
  20 static void (*tegra_hotplug_shutdown)(void);
  21
  22 /*
  23  * platform-specific code to shutdown a CPU
  24  *
  25  * Called with IRQs disabled
  26  */
  27 void __ref tegra_cpu_die(unsigned int cpu)
  28 {
  29         cpu = cpu_logical_map(cpu);
  30
  31         /* Flush the L1 data cache. */
  32         flush_cache_all();
  33
  34         /* Shut down the current CPU. */
  35         tegra_hotplug_shutdown();
  36
  37         /* Clock gate the CPU */
  38         tegra_wait_cpu_in_reset(cpu);
  39         tegra_disable_cpu_clock(cpu);
  40
  41         /* Should never return here. */
  42         BUG();
  43 }
  44
  45 int tegra_cpu_disable(unsigned int cpu)
  46 {
  47         /*
  48          * we don't allow CPU 0 to be shutdown (it is still too special
  49          * e.g. clock tick interrupts)
  50          */
  51         return cpu == 0 ? -EPERM : 0;
  52 }
  53
  54 #ifdef CONFIG_ARCH_TEGRA_2x_SOC
  55 extern void tegra20_hotplug_shutdown(void);
  56 void __init tegra20_hotplug_init(void)
  57 {
  58         tegra_hotplug_shutdown = tegra20_hotplug_shutdown;
  59 }
  60 #endif
  61
  62 #ifdef CONFIG_ARCH_TEGRA_3x_SOC
  63 extern void tegra30_hotplug_shutdown(void);
  64 void __init tegra30_hotplug_init(void)
  65 {
  66         tegra_hotplug_shutdown = tegra30_hotplug_shutdown;
  67 }
  68 #endif