arch/arm/mach-highbank/platsmp.c

   1 /*
   2  * Copyright 2010-2011 Calxeda, Inc.
   3  * Based on platsmp.c, Copyright (C) 2002 ARM Ltd.
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms and conditions of the GNU General Public License,
   7  * version 2, as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12  * more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along with
  15  * this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17 #include <linux/init.h>
  18 #include <linux/smp.h>
  19 #include <linux/io.h>
  20
  21 #include <asm/smp_scu.h>
  22
  23 #include "core.h"
  24
  25 extern void secondary_startup(void);
  26
  27 static int highbank_boot_secondary(unsigned int cpu, struct task_struct *idle)
  28 {
  29         highbank_set_cpu_jump(cpu, secondary_startup);
  30         arch_send_wakeup_ipi_mask(cpumask_of(cpu));
  31         return 0;
  32 }
  33
  34 /*
  35  * Initialise the CPU possible map early - this describes the CPUs
  36  * which may be present or become present in the system.
  37  */
  38 static void __init highbank_smp_init_cpus(void)
  39 {
  40         unsigned int i, ncores = 4;
  41
  42         /* sanity check */
  43         if (ncores > NR_CPUS) {
  44                 printk(KERN_WARNING
  45                        "highbank: no. of cores (%d) greater than configured "
  46                        "maximum of %d - clipping\n",
  47                        ncores, NR_CPUS);
  48                 ncores = NR_CPUS;
  49         }
  50
  51         for (i = 0; i < ncores; i++)
  52                 set_cpu_possible(i, true);
  53 }
  54
  55 static void __init highbank_smp_prepare_cpus(unsigned int max_cpus)
  56 {
  57         if (scu_base_addr)
  58                 scu_enable(scu_base_addr);
  59 }
  60
  61 struct smp_operations highbank_smp_ops __initdata = {
  62         .smp_init_cpus          = highbank_smp_init_cpus,
  63         .smp_prepare_cpus       = highbank_smp_prepare_cpus,
  64         .smp_boot_secondary     = highbank_boot_secondary,
  65 #ifdef CONFIG_HOTPLUG_CPU
  66         .cpu_die                = highbank_cpu_die,
  67 #endif
  68 };