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       1                 :            : /*
       2                 :            :  * This program is free software; you can redistribute it and/or modify
       3                 :            :  * it under the terms of the GNU General Public License version 2 as
       4                 :            :  * published by the Free Software Foundation.
       5                 :            :  *
       6                 :            :  * This program is distributed in the hope that it will be useful,
       7                 :            :  * but WITHOUT ANY WARRANTY; without even the implied warranty of
       8                 :            :  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
       9                 :            :  * GNU General Public License for more details.
      10                 :            :  *
      11                 :            :  * Copyright (C) 2012 ARM Limited
      12                 :            :  *
      13                 :            :  * Author: Will Deacon <will.deacon@arm.com>
      14                 :            :  */
      15                 :            : 
      16                 :            : #include <linux/init.h>
      17                 :            : #include <linux/smp.h>
      18                 :            : #include <linux/of.h>
      19                 :            : 
      20                 :            : #include <asm/psci.h>
      21                 :            : #include <asm/smp_plat.h>
      22                 :            : 
      23                 :            : /*
      24                 :            :  * psci_smp assumes that the following is true about PSCI:
      25                 :            :  *
      26                 :            :  * cpu_suspend   Suspend the execution on a CPU
      27                 :            :  * @state        we don't currently describe affinity levels, so just pass 0.
      28                 :            :  * @entry_point  the first instruction to be executed on return
      29                 :            :  * returns 0  success, < 0 on failure
      30                 :            :  *
      31                 :            :  * cpu_off       Power down a CPU
      32                 :            :  * @state        we don't currently describe affinity levels, so just pass 0.
      33                 :            :  * no return on successful call
      34                 :            :  *
      35                 :            :  * cpu_on        Power up a CPU
      36                 :            :  * @cpuid        cpuid of target CPU, as from MPIDR
      37                 :            :  * @entry_point  the first instruction to be executed on return
      38                 :            :  * returns 0  success, < 0 on failure
      39                 :            :  *
      40                 :            :  * migrate       Migrate the context to a different CPU
      41                 :            :  * @cpuid        cpuid of target CPU, as from MPIDR
      42                 :            :  * returns 0  success, < 0 on failure
      43                 :            :  *
      44                 :            :  */
      45                 :            : 
      46                 :            : extern void secondary_startup(void);
      47                 :            : 
      48                 :          0 : static int psci_boot_secondary(unsigned int cpu, struct task_struct *idle)
      49                 :            : {
      50         [ #  # ]:          0 :         if (psci_ops.cpu_on)
      51                 :          0 :                 return psci_ops.cpu_on(cpu_logical_map(cpu),
      52                 :          0 :                                        __pa(secondary_startup));
      53                 :            :         return -ENODEV;
      54                 :            : }
      55                 :            : 
      56                 :            : #ifdef CONFIG_HOTPLUG_CPU
      57                 :          0 : void __ref psci_cpu_die(unsigned int cpu)
      58                 :            : {
      59                 :          0 :        const struct psci_power_state ps = {
      60                 :            :                .type = PSCI_POWER_STATE_TYPE_POWER_DOWN,
      61                 :            :        };
      62                 :            : 
      63         [ #  # ]:          0 :        if (psci_ops.cpu_off)
      64                 :          0 :                psci_ops.cpu_off(ps);
      65                 :            : 
      66                 :            :        /* We should never return */
      67                 :          0 :        panic("psci: cpu %d failed to shutdown\n", cpu);
      68                 :            : }
      69                 :            : #endif
      70                 :            : 
      71                 :          0 : bool __init psci_smp_available(void)
      72                 :            : {
      73                 :            :         /* is cpu_on available at least? */
      74                 :          0 :         return (psci_ops.cpu_on != NULL);
      75                 :            : }
      76                 :            : 
      77                 :            : struct smp_operations __initdata psci_smp_ops = {
      78                 :            :         .smp_boot_secondary     = psci_boot_secondary,
      79                 :            : #ifdef CONFIG_HOTPLUG_CPU
      80                 :            :         .cpu_die                = psci_cpu_die,
      81                 :            : #endif
      82                 :            : };