arch/powerpc/platforms/86xx/mpc86xx_smp.c

   1 /*
   2  * Author: Xianghua Xiao <x.xiao@freescale.com>
   3  *         Zhang Wei <wei.zhang@freescale.com>
   4  *
   5  * Copyright 2006 Freescale Semiconductor Inc.
   6  *
   7  * This program is free software; you can redistribute  it and/or modify it
   8  * under  the terms of  the GNU General  Public License as published by the
   9  * Free Software Foundation;  either version 2 of the  License, or (at your
  10  * option) any later version.
  11  */
  12
  13 #include <linux/stddef.h>
  14 #include <linux/kernel.h>
  15 #include <linux/init.h>
  16 #include <linux/delay.h>
  17
  18 #include <asm/code-patching.h>
  19 #include <asm/page.h>
  20 #include <asm/pgtable.h>
  21 #include <asm/pci-bridge.h>
  22 #include <asm/mpic.h>
  23 #include <asm/cacheflush.h>
  24
  25 #include <sysdev/fsl_soc.h>
  26
  27 #include "mpc86xx.h"
  28
  29 extern void __secondary_start_mpc86xx(void);
  30
  31 #define MCM_PORT_CONFIG_OFFSET  0x10
  32
  33 /* Offset from CCSRBAR */
  34 #define MPC86xx_MCM_OFFSET      (0x1000)
  35 #define MPC86xx_MCM_SIZE        (0x1000)
  36
  37 static void __init
  38 smp_86xx_release_core(int nr)
  39 {
  40         __be32 __iomem *mcm_vaddr;
  41         unsigned long pcr;
  42
  43         if (nr < 0 || nr >= NR_CPUS)
  44                 return;
  45
  46         /*
  47          * Startup Core #nr.
  48          */
  49         mcm_vaddr = ioremap(get_immrbase() + MPC86xx_MCM_OFFSET,
  50                             MPC86xx_MCM_SIZE);
  51         pcr = in_be32(mcm_vaddr + (MCM_PORT_CONFIG_OFFSET >> 2));
  52         pcr |= 1 << (nr + 24);
  53         out_be32(mcm_vaddr + (MCM_PORT_CONFIG_OFFSET >> 2), pcr);
  54
  55         iounmap(mcm_vaddr);
  56 }
  57
  58
  59 static int __init
  60 smp_86xx_kick_cpu(int nr)
  61 {
  62         unsigned int save_vector;
  63         unsigned long target, flags;
  64         int n = 0;
  65         unsigned int *vector = (unsigned int *)(KERNELBASE + 0x100);
  66
  67         if (nr < 0 || nr >= NR_CPUS)
  68                 return -ENOENT;
  69
  70         pr_debug("smp_86xx_kick_cpu: kick CPU #%d\n", nr);
  71
  72         local_irq_save(flags);
  73
  74         /* Save reset vector */
  75         save_vector = *vector;
  76
  77         /* Setup fake reset vector to call __secondary_start_mpc86xx. */
  78         target = (unsigned long) __secondary_start_mpc86xx;
  79         patch_branch(vector, target, BRANCH_SET_LINK);
  80
  81         /* Kick that CPU */
  82         smp_86xx_release_core(nr);
  83
  84         /* Wait a bit for the CPU to take the exception. */
  85         while ((__secondary_hold_acknowledge != nr) && (n++, n < 1000))
  86                 mdelay(1);
  87
  88         /* Restore the exception vector */
  89         *vector = save_vector;
  90         flush_icache_range((unsigned long) vector, (unsigned long) vector + 4);
  91
  92         local_irq_restore(flags);
  93
  94         pr_debug("wait CPU #%d for %d msecs.\n", nr, n);
  95
  96         return 0;
  97 }
  98
  99
 100 static void __init
 101 smp_86xx_setup_cpu(int cpu_nr)
 102 {
 103         mpic_setup_this_cpu();
 104 }
 105
 106
 107 struct smp_ops_t smp_86xx_ops = {
 108         .cause_nmi_ipi = NULL,
 109         .message_pass = smp_mpic_message_pass,
 110         .probe = smp_mpic_probe,
 111         .kick_cpu = smp_86xx_kick_cpu,
 112         .setup_cpu = smp_86xx_setup_cpu,
 113         .take_timebase = smp_generic_take_timebase,
 114         .give_timebase = smp_generic_give_timebase,
 115 };
 116
 117
 118 void __init
 119 mpc86xx_smp_init(void)
 120 {
 121         smp_ops = &smp_86xx_ops;
 122 }