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 static int sh73a0_boot_secondary(unsigned int cpu, struct task_struct *idle)
  37 {
  38         unsigned int lcpu = cpu_logical_map(cpu);
  39
  40         if (((__raw_readl(PSTR) >> (4 * lcpu)) & 3) == 3)
  41                 __raw_writel(1 << lcpu, WUPCR); /* wake up */
  42         else
  43                 __raw_writel(1 << lcpu, SRESCR);        /* reset */
  44
  45         return 0;
  46 }
  47
  48 static void __init sh73a0_smp_prepare_cpus(unsigned int max_cpus)
  49 {
  50         /* Map the reset vector (in headsmp.S) */
  51         __raw_writel(0, APARMBAREA);      /* 4k */
  52         __raw_writel(__pa(shmobile_boot_vector), SBAR);
  53
  54         /* setup sh73a0 specific SCU bits */
  55         shmobile_scu_base = IOMEM(SH73A0_SCU_BASE);
  56         shmobile_smp_scu_prepare_cpus(max_cpus);
  57 }
  58
  59 struct smp_operations sh73a0_smp_ops __initdata = {
  60         .smp_prepare_cpus       = sh73a0_smp_prepare_cpus,
  61         .smp_boot_secondary     = sh73a0_boot_secondary,
  62 #ifdef CONFIG_HOTPLUG_CPU
  63         .cpu_can_disable        = shmobile_smp_cpu_can_disable,
  64         .cpu_die                = shmobile_smp_scu_cpu_die,
  65         .cpu_kill               = shmobile_smp_scu_cpu_kill,
  66 #endif
  67 };