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 extern unsigned long __secondary_hold_acknowledge;
  31
  32 #define MCM_PORT_CONFIG_OFFSET  0x10
  33
  34 /* Offset from CCSRBAR */
  35 #define MPC86xx_MCM_OFFSET      (0x1000)
  36 #define MPC86xx_MCM_SIZE        (0x1000)
  37
  38 static void __init
  39 smp_86xx_release_core(int nr)
  40 {
  41         __be32 __iomem *mcm_vaddr;
  42         unsigned long pcr;
  43
  44         if (nr < 0 || nr >= NR_CPUS)
  45                 return;
  46
  47         /*
  48          * Startup Core #nr.
  49          */
  50         mcm_vaddr = ioremap(get_immrbase() + MPC86xx_MCM_OFFSET,
  51                             MPC86xx_MCM_SIZE);
  52         pcr = in_be32(mcm_vaddr + (MCM_PORT_CONFIG_OFFSET >> 2));
  53         pcr |= 1 << (nr + 24);
  54         out_be32(mcm_vaddr + (MCM_PORT_CONFIG_OFFSET >> 2), pcr);
  55
  56         iounmap(mcm_vaddr);
  57 }
  58
  59
  60 static void __init
  61 smp_86xx_kick_cpu(int nr)
  62 {
  63         unsigned int save_vector;
  64         unsigned long target, flags;
  65         int n = 0;
  66         unsigned int *vector = (unsigned int *)(KERNELBASE + 0x100);
  67
  68         if (nr < 0 || nr >= NR_CPUS)
  69                 return;
  70
  71         pr_debug("smp_86xx_kick_cpu: kick CPU #%d\n", nr);
  72
  73         local_irq_save(flags);
  74
  75         /* Save reset vector */
  76         save_vector = *vector;
  77
  78         /* Setup fake reset vector to call __secondary_start_mpc86xx. */
  79         target = (unsigned long) __secondary_start_mpc86xx;
  80         patch_branch(vector, target, BRANCH_SET_LINK);
  81
  82         /* Kick that CPU */
  83         smp_86xx_release_core(nr);
  84
  85         /* Wait a bit for the CPU to take the exception. */
  86         while ((__secondary_hold_acknowledge != nr) && (n++, n < 1000))
  87                 mdelay(1);
  88
  89         /* Restore the exception vector */
  90         *vector = save_vector;
  91         flush_icache_range((unsigned long) vector, (unsigned long) vector + 4);
  92
  93         local_irq_restore(flags);
  94
  95         pr_debug("wait CPU #%d for %d msecs.\n", nr, n);
  96 }
  97
  98
  99 static void __init
 100 smp_86xx_setup_cpu(int cpu_nr)
 101 {
 102         mpic_setup_this_cpu();
 103 }
 104
 105
 106 struct smp_ops_t smp_86xx_ops = {
 107         .message_pass = smp_mpic_message_pass,
 108         .probe = smp_mpic_probe,
 109         .kick_cpu = smp_86xx_kick_cpu,
 110         .setup_cpu = smp_86xx_setup_cpu,
 111         .take_timebase = smp_generic_take_timebase,
 112         .give_timebase = smp_generic_give_timebase,
 113 };
 114
 115
 116 void __init
 117 mpc86xx_smp_init(void)
 118 {
 119         smp_ops = &smp_86xx_ops;
 120 }