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/pgtable.h>
  19 #include <asm/page.h>
  20 #include <asm/pci-bridge.h>
  21 #include <asm-powerpc/mpic.h>
  22 #include <asm/mpc86xx.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
  33 static void __init
  34 smp_86xx_release_core(int nr)
  35 {
  36         __be32 __iomem *mcm_vaddr;
  37         unsigned long pcr;
  38
  39         if (nr < 0 || nr >= NR_CPUS)
  40                 return;
  41
  42         /*
  43          * Startup Core #nr.
  44          */
  45         mcm_vaddr = ioremap(get_immrbase() + MPC86xx_MCM_OFFSET,
  46                             MPC86xx_MCM_SIZE);
  47         pcr = in_be32(mcm_vaddr + (MCM_PORT_CONFIG_OFFSET >> 2));
  48         pcr |= 1 << (nr + 24);
  49         out_be32(mcm_vaddr + (MCM_PORT_CONFIG_OFFSET >> 2), pcr);
  50 }
  51
  52
  53 static void __init
  54 smp_86xx_kick_cpu(int nr)
  55 {
  56         unsigned int save_vector;
  57         unsigned long target, flags;
  58         int n = 0;
  59         volatile unsigned int *vector
  60                  = (volatile unsigned int *)(KERNELBASE + 0x100);
  61
  62         if (nr < 0 || nr >= NR_CPUS)
  63                 return;
  64
  65         pr_debug("smp_86xx_kick_cpu: kick CPU #%d\n", nr);
  66
  67         local_irq_save(flags);
  68         local_irq_disable();
  69
  70         /* Save reset vector */
  71         save_vector = *vector;
  72
  73         /* Setup fake reset vector to call __secondary_start_mpc86xx. */
  74         target = (unsigned long) __secondary_start_mpc86xx;
  75         create_branch((unsigned long)vector, target, BRANCH_SET_LINK);
  76
  77         /* Kick that CPU */
  78         smp_86xx_release_core(nr);
  79
  80         /* Wait a bit for the CPU to take the exception. */
  81         while ((__secondary_hold_acknowledge != nr) && (n++, n < 1000))
  82                 mdelay(1);
  83
  84         /* Restore the exception vector */
  85         *vector = save_vector;
  86         flush_icache_range((unsigned long) vector, (unsigned long) vector + 4);
  87
  88         local_irq_restore(flags);
  89
  90         pr_debug("wait CPU #%d for %d msecs.\n", nr, n);
  91 }
  92
  93
  94 static void __init
  95 smp_86xx_setup_cpu(int cpu_nr)
  96 {
  97         mpic_setup_this_cpu();
  98 }
  99
 100
 101 struct smp_ops_t smp_86xx_ops = {
 102         .message_pass = smp_mpic_message_pass,
 103         .probe = smp_mpic_probe,
 104         .kick_cpu = smp_86xx_kick_cpu,
 105         .setup_cpu = smp_86xx_setup_cpu,
 106         .take_timebase = smp_generic_take_timebase,
 107         .give_timebase = smp_generic_give_timebase,
 108 };
 109
 110
 111 void __init
 112 mpc86xx_smp_init(void)
 113 {
 114         smp_ops = &smp_86xx_ops;
 115 }