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
  25 static int __init smp_psci_init_cpu(struct device_node *dn, int cpu)
  26 {
  27         return 0;
  28 }
  29
  30 static int __init smp_psci_prepare_cpu(int cpu)
  31 {
  32         int err;
  33
  34         if (!psci_ops.cpu_on) {
  35                 pr_err("psci: no cpu_on method, not booting CPU%d\n", cpu);
  36                 return -ENODEV;
  37         }
  38
  39         err = psci_ops.cpu_on(cpu, __pa(secondary_holding_pen));
  40         if (err) {
  41                 pr_err("psci: failed to boot CPU%d (%d)\n", cpu, err);
  42                 return err;
  43         }
  44
  45         return 0;
  46 }
  47
  48 const struct smp_enable_ops smp_psci_ops __initconst = {
  49         .name           = "psci",
  50         .init_cpu       = smp_psci_init_cpu,
  51         .prepare_cpu    = smp_psci_prepare_cpu,
  52 };