arch/arm/mach-vexpress/platsmp.c

   1 /*
   2  *  linux/arch/arm/mach-vexpress/platsmp.c
   3  *
   4  *  Copyright (C) 2002 ARM Ltd.
   5  *  All Rights Reserved
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11 #include <linux/init.h>
  12 #include <linux/errno.h>
  13 #include <linux/smp.h>
  14 #include <linux/io.h>
  15 #include <linux/of_address.h>
  16 #include <linux/vexpress.h>
  17
  18 #include <asm/mcpm.h>
  19 #include <asm/smp_scu.h>
  20 #include <asm/mach/map.h>
  21
  22 #include <mach/motherboard.h>
  23
  24 #include <plat/platsmp.h>
  25
  26 #include "core.h"
  27
  28 /*
  29  * Initialise the CPU possible map early - this describes the CPUs
  30  * which may be present or become present in the system.
  31  */
  32 static void __init vexpress_smp_init_cpus(void)
  33 {
  34         ct_desc->init_cpu_map();
  35 }
  36
  37 static void __init vexpress_smp_prepare_cpus(unsigned int max_cpus)
  38 {
  39         /*
  40          * Initialise the present map, which describes the set of CPUs
  41          * actually populated at the present time.
  42          */
  43         ct_desc->smp_enable(max_cpus);
  44
  45         /*
  46          * Write the address of secondary startup into the
  47          * system-wide flags register. The boot monitor waits
  48          * until it receives a soft interrupt, and then the
  49          * secondary CPU branches to this address.
  50          */
  51         vexpress_flags_set(virt_to_phys(versatile_secondary_startup));
  52 }
  53
  54 struct smp_operations __initdata vexpress_smp_ops = {
  55         .smp_init_cpus          = vexpress_smp_init_cpus,
  56         .smp_prepare_cpus       = vexpress_smp_prepare_cpus,
  57         .smp_secondary_init     = versatile_secondary_init,
  58         .smp_boot_secondary     = versatile_boot_secondary,
  59 #ifdef CONFIG_HOTPLUG_CPU
  60         .cpu_die                = vexpress_cpu_die,
  61 #endif
  62 };
  63
  64 bool __init vexpress_smp_init_ops(void)
  65 {
  66 #ifdef CONFIG_MCPM
  67         /*
  68          * The best way to detect a multi-cluster configuration at the moment
  69          * is to look for the presence of a CCI in the system.
  70          * Override the default vexpress_smp_ops if so.
  71          */
  72         struct device_node *node;
  73         node = of_find_compatible_node(NULL, NULL, "arm,cci-400");
  74         if (node && of_device_is_available(node)) {
  75                 mcpm_smp_set_ops();
  76                 return true;
  77         }
  78 #endif
  79         return false;
  80 }
  81
  82 #if defined(CONFIG_OF)
  83
  84 static const struct of_device_id vexpress_smp_dt_scu_match[] __initconst = {
  85         { .compatible = "arm,cortex-a5-scu", },
  86         { .compatible = "arm,cortex-a9-scu", },
  87         {}
  88 };
  89
  90 static void __init vexpress_smp_dt_prepare_cpus(unsigned int max_cpus)
  91 {
  92         struct device_node *scu = of_find_matching_node(NULL,
  93                         vexpress_smp_dt_scu_match);
  94
  95         if (scu)
  96                 scu_enable(of_iomap(scu, 0));
  97
  98         /*
  99          * Write the address of secondary startup into the
 100          * system-wide flags register. The boot monitor waits
 101          * until it receives a soft interrupt, and then the
 102          * secondary CPU branches to this address.
 103          */
 104         vexpress_flags_set(virt_to_phys(versatile_secondary_startup));
 105 }
 106
 107 struct smp_operations __initdata vexpress_smp_dt_ops = {
 108         .smp_prepare_cpus       = vexpress_smp_dt_prepare_cpus,
 109         .smp_secondary_init     = versatile_secondary_init,
 110         .smp_boot_secondary     = versatile_boot_secondary,
 111 #ifdef CONFIG_HOTPLUG_CPU
 112         .cpu_die                = vexpress_cpu_die,
 113 #endif
 114 };
 115
 116 #endif