/*
   * Copyright (C) 2012-2013 Xilinx
   *
   * based on linux/arch/arm/mach-realview/hotplug.c
   *
   * Copyright (C) 2002 ARM Ltd.
   * All Rights Reserved
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License version 2 as
   * published by the Free Software Foundation.
   */
  #include <linux/kernel.h>
  #include <linux/errno.h>
  #include <linux/smp.h>
  
  #include <asm/cacheflush.h>
  #include <asm/cp15.h>
  #include "common.h"
  
  static inline void zynq_cpu_enter_lowpower(void)
  {
  	unsigned int v;
  
  	flush_cache_all();
  	asm volatile(
  	"	mcr	p15, 0, %1, c7, c5, 0
  "
  	"	dsb
  "
  	/*
  	 * Turn off coherency
  	 */
  	"	mrc	p15, 0, %0, c1, c0, 1
  "
  	"	bic	%0, %0, #0x40
  "
  	"	mcr	p15, 0, %0, c1, c0, 1
  "
  	"	mrc	p15, 0, %0, c1, c0, 0
  "
  	"	bic	%0, %0, %2
  "
  	"	mcr	p15, 0, %0, c1, c0, 0
  "
  	  : "=&r" (v)
  	  : "r" (0), "Ir" (CR_C)
  	  : "cc");
  }
  
  /*
   * platform-specific code to shutdown a CPU
   *
   * Called with IRQs disabled
   */
  void zynq_platform_cpu_die(unsigned int cpu)
  {
  	zynq_cpu_enter_lowpower();
  
  	/*
  	 * there is no power-control hardware on this platform, so all
  	 * we can do is put the core into WFI; this is safe as the calling
  	 * code will have already disabled interrupts
  	 */
  	for (;;)
  		cpu_do_idle();
  }