arch/arm/mach-imx/hotplug.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Copyright 2011 Freescale Semiconductor, Inc.
   4  * Copyright 2011 Linaro Ltd.
   5  */
   6
   7 #include <linux/errno.h>
   8 #include <linux/jiffies.h>
   9 #include <asm/cacheflush.h>
  10 #include <asm/cp15.h>
  11 #include <asm/proc-fns.h>
  12
  13 #include "common.h"
  14 #include "hardware.h"
  15
  16 /*
  17  * platform-specific code to shutdown a CPU
  18  *
  19  * Called with IRQs disabled
  20  */
  21 void imx_cpu_die(unsigned int cpu)
  22 {
  23         v7_exit_coherency_flush(louis);
  24         /*
  25          * We use the cpu jumping argument register to sync with
  26          * imx_cpu_kill() which is running on cpu0 and waiting for
  27          * the register being cleared to kill the cpu.
  28          */
  29         imx_set_cpu_arg(cpu, ~0);
  30
  31         while (1)
  32                 cpu_do_idle();
  33 }
  34
  35 int imx_cpu_kill(unsigned int cpu)
  36 {
  37         unsigned long timeout = jiffies + msecs_to_jiffies(50);
  38
  39         while (imx_get_cpu_arg(cpu) == 0)
  40                 if (time_after(jiffies, timeout))
  41                         return 0;
  42         imx_enable_cpu(cpu, false);
  43         imx_set_cpu_arg(cpu, 0);
  44         if (cpu_is_imx7d())
  45                 imx_gpcv2_set_core1_pdn_pup_by_software(true);
  46         return 1;
  47 }