arch/arm/mach-ux500/hotplug.c

   1 /*
   2  * Copyright (C) STMicroelectronics 2009
   3  * Copyright (C) ST-Ericsson SA 2010
   4  *
   5  * License Terms: GNU General Public License v2
   6  *      Based on ARM realview platform
   7  *
   8  * Author: Sundar Iyer <sundar.iyer@stericsson.com>
   9  *
  10  */
  11 #include <linux/kernel.h>
  12 #include <linux/errno.h>
  13 #include <linux/smp.h>
  14
  15 #include <asm/cacheflush.h>
  16 #include <asm/smp_plat.h>
  17
  18 #include <mach/setup.h>
  19
  20 /*
  21  * platform-specific code to shutdown a CPU
  22  *
  23  * Called with IRQs disabled
  24  */
  25 void __ref ux500_cpu_die(unsigned int cpu)
  26 {
  27         flush_cache_all();
  28
  29         /* directly enter low power state, skipping secure registers */
  30         for (;;) {
  31                 __asm__ __volatile__("dsb\n\t" "wfi\n\t"
  32                                 : : : "memory");
  33                 if (pen_release == cpu_logical_map(cpu)) {
  34                         /*
  35                          * OK, proper wakeup, we're done
  36                          */
  37                         break;
  38                 }
  39         }
  40 }