hotplug.c

Go to the documentation of this file.

/*
 * Copyright 2011 Freescale Semiconductor, Inc.
 * Copyright 2011 Linaro Ltd.
 *
 * The code contained herein is licensed under the GNU General Public
 * License. You may obtain a copy of the GNU General Public License
 * Version 2 or later at the following locations:
 *
 * http://www.opensource.org/licenses/gpl-license.html
 * http://www.gnu.org/copyleft/gpl.html
 */

#include <linux/errno.h>
#include <asm/cacheflush.h>
#include <asm/cp15.h>
#include <mach/common.h>

static inline void cpu_enter_lowpower(void)
{
    unsigned int v;

    flush_cache_all();
    asm volatile(
        "mcr    p15, 0, %1, c7, c5, 0\n"
    "   mcr p15, 0, %1, c7, c10, 4\n"
    /*
     * Turn off coherency
     */
    "   mrc p15, 0, %0, c1, c0, 1\n"
    "   bic %0, %0, %3\n"
    "   mcr p15, 0, %0, c1, c0, 1\n"
    "   mrc p15, 0, %0, c1, c0, 0\n"
    "   bic %0, %0, %2\n"
    "   mcr p15, 0, %0, c1, c0, 0\n"
      : "=&r" (v)
      : "r" (0), "Ir" (CR_C), "Ir" (0x40)
      : "cc");
}

/*
 * platform-specific code to shutdown a CPU
 *
 * Called with IRQs disabled
 */
void imx_cpu_die(unsigned int cpu)
{
    cpu_enter_lowpower();
    imx_enable_cpu(cpu, false);

    /* spin here until hardware takes it down */
    while (1)
        ;
}