arch/arm/mach-shmobile/smp-r8a7779.c

   1 /*
   2  * SMP support for R-Mobile / SH-Mobile - r8a7779 portion
   3  *
   4  * Copyright (C) 2011  Renesas Solutions Corp.
   5  * Copyright (C) 2011  Magnus Damm
   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 as published by
   9  * the Free Software Foundation; version 2 of the License.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  19  */
  20 #include <linux/kernel.h>
  21 #include <linux/init.h>
  22 #include <linux/smp.h>
  23 #include <linux/spinlock.h>
  24 #include <linux/io.h>
  25 #include <linux/delay.h>
  26 #include <mach/common.h>
  27 #include <mach/r8a7779.h>
  28 #include <asm/cacheflush.h>
  29 #include <asm/smp_plat.h>
  30 #include <asm/smp_scu.h>
  31 #include <asm/smp_twd.h>
  32
  33 #define AVECR IOMEM(0xfe700040)
  34 #define R8A7779_SCU_BASE 0xf0000000
  35
  36 static struct r8a7779_pm_ch r8a7779_ch_cpu1 = {
  37         .chan_offs = 0x40, /* PWRSR0 .. PWRER0 */
  38         .chan_bit = 1, /* ARM1 */
  39         .isr_bit = 1, /* ARM1 */
  40 };
  41
  42 static struct r8a7779_pm_ch r8a7779_ch_cpu2 = {
  43         .chan_offs = 0x40, /* PWRSR0 .. PWRER0 */
  44         .chan_bit = 2, /* ARM2 */
  45         .isr_bit = 2, /* ARM2 */
  46 };
  47
  48 static struct r8a7779_pm_ch r8a7779_ch_cpu3 = {
  49         .chan_offs = 0x40, /* PWRSR0 .. PWRER0 */
  50         .chan_bit = 3, /* ARM3 */
  51         .isr_bit = 3, /* ARM3 */
  52 };
  53
  54 static struct r8a7779_pm_ch *r8a7779_ch_cpu[4] = {
  55         [1] = &r8a7779_ch_cpu1,
  56         [2] = &r8a7779_ch_cpu2,
  57         [3] = &r8a7779_ch_cpu3,
  58 };
  59
  60 #ifdef CONFIG_HAVE_ARM_TWD
  61 static DEFINE_TWD_LOCAL_TIMER(twd_local_timer, R8A7779_SCU_BASE + 0x600, 29);
  62 void __init r8a7779_register_twd(void)
  63 {
  64         twd_local_timer_register(&twd_local_timer);
  65 }
  66 #endif
  67
  68 static int r8a7779_platform_cpu_kill(unsigned int cpu)
  69 {
  70         struct r8a7779_pm_ch *ch = NULL;
  71         int ret = -EIO;
  72
  73         cpu = cpu_logical_map(cpu);
  74
  75         if (cpu < ARRAY_SIZE(r8a7779_ch_cpu))
  76                 ch = r8a7779_ch_cpu[cpu];
  77
  78         if (ch)
  79                 ret = r8a7779_sysc_power_down(ch);
  80
  81         return ret ? ret : 1;
  82 }
  83
  84 static int r8a7779_boot_secondary(unsigned int cpu, struct task_struct *idle)
  85 {
  86         struct r8a7779_pm_ch *ch = NULL;
  87         unsigned int lcpu = cpu_logical_map(cpu);
  88         int ret;
  89
  90         if (lcpu < ARRAY_SIZE(r8a7779_ch_cpu))
  91                 ch = r8a7779_ch_cpu[lcpu];
  92
  93         if (ch)
  94                 ret = r8a7779_sysc_power_up(ch);
  95         else
  96                 ret = -EIO;
  97
  98         return ret;
  99 }
 100
 101 static void __init r8a7779_smp_prepare_cpus(unsigned int max_cpus)
 102 {
 103         /* Map the reset vector (in headsmp-scu.S, headsmp.S) */
 104         __raw_writel(__pa(shmobile_boot_vector), AVECR);
 105         shmobile_boot_fn = virt_to_phys(shmobile_boot_scu);
 106         shmobile_boot_arg = (unsigned long)shmobile_scu_base;
 107
 108         /* setup r8a7779 specific SCU bits */
 109         shmobile_scu_base = IOMEM(R8A7779_SCU_BASE);
 110         shmobile_smp_scu_prepare_cpus(max_cpus);
 111
 112         r8a7779_pm_init();
 113
 114         /* power off secondary CPUs */
 115         r8a7779_platform_cpu_kill(1);
 116         r8a7779_platform_cpu_kill(2);
 117         r8a7779_platform_cpu_kill(3);
 118 }
 119
 120 #ifdef CONFIG_HOTPLUG_CPU
 121 static int r8a7779_cpu_kill(unsigned int cpu)
 122 {
 123         if (shmobile_smp_scu_cpu_kill(cpu))
 124                 return r8a7779_platform_cpu_kill(cpu);
 125
 126         return 0;
 127 }
 128
 129 static int r8a7779_cpu_disable(unsigned int cpu)
 130 {
 131         /* only CPU1->3 have power domains, do not allow hotplug of CPU0 */
 132         return cpu == 0 ? -EPERM : 0;
 133 }
 134 #endif /* CONFIG_HOTPLUG_CPU */
 135
 136 struct smp_operations r8a7779_smp_ops  __initdata = {
 137         .smp_prepare_cpus       = r8a7779_smp_prepare_cpus,
 138         .smp_boot_secondary     = r8a7779_boot_secondary,
 139 #ifdef CONFIG_HOTPLUG_CPU
 140         .cpu_disable            = r8a7779_cpu_disable,
 141         .cpu_die                = shmobile_smp_scu_cpu_die,
 142         .cpu_kill               = r8a7779_cpu_kill,
 143 #endif
 144 };