arch/arm64/kernel/smp_psci.c

   1 /*
   2  * PSCI SMP initialisation
   3  *
   4  * Copyright (C) 2013 ARM Ltd.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19 #include <linux/init.h>
  20 #include <linux/of.h>
  21 #include <linux/smp.h>
  22
  23 #include <asm/psci.h>
  24 #include <asm/smp_plat.h>
  25
  26 static int __init smp_psci_init_cpu(struct device_node *dn, int cpu)
  27 {
  28         return 0;
  29 }
  30
  31 static int __init smp_psci_prepare_cpu(int cpu)
  32 {
  33         int err;
  34
  35         if (!psci_ops.cpu_on) {
  36                 pr_err("psci: no cpu_on method, not booting CPU%d\n", cpu);
  37                 return -ENODEV;
  38         }
  39
  40         err = psci_ops.cpu_on(cpu_logical_map(cpu), __pa(secondary_holding_pen));
  41         if (err) {
  42                 pr_err("psci: failed to boot CPU%d (%d)\n", cpu, err);
  43                 return err;
  44         }
  45
  46         return 0;
  47 }
  48
  49 const struct smp_enable_ops smp_psci_ops __initconst = {
  50         .name           = "psci",
  51         .init_cpu       = smp_psci_init_cpu,
  52         .prepare_cpu    = smp_psci_prepare_cpu,
  53 };