arch/arm/mach-shmobile/smp-sh73a0.c

   1 /*
   2  * SMP support for R-Mobile / SH-Mobile - sh73a0 portion
   3  *
   4  * Copyright (C) 2010  Magnus Damm
   5  * Copyright (C) 2010  Takashi Yoshii
   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/io.h>
  24 #include <linux/delay.h>
  25 #include <mach/common.h>
  26 #include <mach/sh73a0.h>
  27 #include <asm/smp_plat.h>
  28 #include <asm/smp_twd.h>
  29
  30 #define WUPCR           IOMEM(0xe6151010)
  31 #define SRESCR          IOMEM(0xe6151018)
  32 #define PSTR            IOMEM(0xe6151040)
  33 #define SBAR            IOMEM(0xe6180020)
  34 #define APARMBAREA      IOMEM(0xe6f10020)
  35
  36 #define SH73A0_SCU_BASE 0xf0000000
  37
  38 #ifdef CONFIG_HAVE_ARM_TWD
  39 static DEFINE_TWD_LOCAL_TIMER(twd_local_timer, SH73A0_SCU_BASE + 0x600, 29);
  40 void __init sh73a0_register_twd(void)
  41 {
  42         twd_local_timer_register(&twd_local_timer);
  43 }
  44 #endif
  45
  46 static int sh73a0_boot_secondary(unsigned int cpu, struct task_struct *idle)
  47 {
  48         unsigned int lcpu = cpu_logical_map(cpu);
  49         int ret;
  50
  51         ret = shmobile_smp_scu_boot_secondary(cpu, idle);
  52         if (ret)
  53                 return ret;
  54
  55         if (((__raw_readl(PSTR) >> (4 * lcpu)) & 3) == 3)
  56                 __raw_writel(1 << lcpu, WUPCR); /* wake up */
  57         else
  58                 __raw_writel(1 << lcpu, SRESCR);        /* reset */
  59
  60         return 0;
  61 }
  62
  63 static void __init sh73a0_smp_prepare_cpus(unsigned int max_cpus)
  64 {
  65         /* Map the reset vector (in headsmp.S) */
  66         __raw_writel(0, APARMBAREA);      /* 4k */
  67         __raw_writel(__pa(shmobile_boot_vector), SBAR);
  68
  69         /* setup sh73a0 specific SCU bits */
  70         shmobile_scu_base = IOMEM(SH73A0_SCU_BASE);
  71         shmobile_smp_scu_prepare_cpus(max_cpus);
  72 }
  73
  74 #ifdef CONFIG_HOTPLUG_CPU
  75 static int sh73a0_cpu_disable(unsigned int cpu)
  76 {
  77         return 0; /* CPU0 and CPU1 supported */
  78 }
  79 #endif /* CONFIG_HOTPLUG_CPU */
  80
  81 struct smp_operations sh73a0_smp_ops __initdata = {
  82         .smp_prepare_cpus       = sh73a0_smp_prepare_cpus,
  83         .smp_boot_secondary     = sh73a0_boot_secondary,
  84 #ifdef CONFIG_HOTPLUG_CPU
  85         .cpu_disable            = sh73a0_cpu_disable,
  86         .cpu_die                = shmobile_smp_scu_cpu_die,
  87         .cpu_kill               = shmobile_smp_scu_cpu_kill,
  88 #endif
  89 };