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 #include <linux/kernel.h>
  17 #include <linux/init.h>
  18 #include <linux/smp.h>
  19 #include <linux/io.h>
  20 #include <linux/delay.h>
  21
  22 #include <asm/smp_plat.h>
  23 #include <asm/smp_twd.h>
  24
  25 #include "common.h"
  26 #include "sh73a0.h"
  27
  28 #define WUPCR           IOMEM(0xe6151010)
  29 #define SRESCR          IOMEM(0xe6151018)
  30 #define PSTR            IOMEM(0xe6151040)
  31 #define SBAR            IOMEM(0xe6180020)
  32 #define APARMBAREA      IOMEM(0xe6f10020)
  33
  34 #define SH73A0_SCU_BASE 0xf0000000
  35
  36 #if defined(CONFIG_HAVE_ARM_TWD) && !defined(CONFIG_ARCH_MULTIPLATFORM)
  37 static DEFINE_TWD_LOCAL_TIMER(twd_local_timer, SH73A0_SCU_BASE + 0x600, 29);
  38 void __init sh73a0_register_twd(void)
  39 {
  40         twd_local_timer_register(&twd_local_timer);
  41 }
  42 #endif
  43
  44 static int sh73a0_boot_secondary(unsigned int cpu, struct task_struct *idle)
  45 {
  46         unsigned int lcpu = cpu_logical_map(cpu);
  47
  48         if (((__raw_readl(PSTR) >> (4 * lcpu)) & 3) == 3)
  49                 __raw_writel(1 << lcpu, WUPCR); /* wake up */
  50         else
  51                 __raw_writel(1 << lcpu, SRESCR);        /* reset */
  52
  53         return 0;
  54 }
  55
  56 static void __init sh73a0_smp_prepare_cpus(unsigned int max_cpus)
  57 {
  58         /* Map the reset vector (in headsmp.S) */
  59         __raw_writel(0, APARMBAREA);      /* 4k */
  60         __raw_writel(__pa(shmobile_boot_vector), SBAR);
  61
  62         /* setup sh73a0 specific SCU bits */
  63         shmobile_scu_base = IOMEM(SH73A0_SCU_BASE);
  64         shmobile_smp_scu_prepare_cpus(max_cpus);
  65 }
  66
  67 struct smp_operations sh73a0_smp_ops __initdata = {
  68         .smp_prepare_cpus       = sh73a0_smp_prepare_cpus,
  69         .smp_boot_secondary     = sh73a0_boot_secondary,
  70 #ifdef CONFIG_HOTPLUG_CPU
  71         .cpu_disable            = shmobile_smp_cpu_disable,
  72         .cpu_die                = shmobile_smp_scu_cpu_die,
  73         .cpu_kill               = shmobile_smp_scu_cpu_kill,
  74 #endif
  75 };