arch/powerpc/platforms/85xx/smp.c

   1 /*
   2  * Author: Andy Fleming <afleming@freescale.com>
   3  *         Kumar Gala <galak@kernel.crashing.org>
   4  *
   5  * Copyright 2006-2008 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 #include <linux/of.h>
  18
  19 #include <asm/machdep.h>
  20 #include <asm/pgtable.h>
  21 #include <asm/page.h>
  22 #include <asm/mpic.h>
  23 #include <asm/cacheflush.h>
  24
  25 #include <sysdev/fsl_soc.h>
  26
  27 extern volatile unsigned long __secondary_hold_acknowledge;
  28 extern void __early_start(void);
  29
  30 #define BOOT_ENTRY_ADDR_UPPER   0
  31 #define BOOT_ENTRY_ADDR_LOWER   1
  32 #define BOOT_ENTRY_R3_UPPER     2
  33 #define BOOT_ENTRY_R3_LOWER     3
  34 #define BOOT_ENTRY_RESV         4
  35 #define BOOT_ENTRY_PIR          5
  36 #define BOOT_ENTRY_R6_UPPER     6
  37 #define BOOT_ENTRY_R6_LOWER     7
  38 #define NUM_BOOT_ENTRY          8
  39 #define SIZE_BOOT_ENTRY         (NUM_BOOT_ENTRY * sizeof(u32))
  40
  41 static void __init
  42 smp_85xx_kick_cpu(int nr)
  43 {
  44         unsigned long flags;
  45         const u64 *cpu_rel_addr;
  46         __iomem u32 *bptr_vaddr;
  47         struct device_node *np;
  48         int n = 0;
  49
  50         WARN_ON (nr < 0 || nr >= NR_CPUS);
  51
  52         pr_debug("smp_85xx_kick_cpu: kick CPU #%d\n", nr);
  53
  54         local_irq_save(flags);
  55
  56         np = of_get_cpu_node(nr, NULL);
  57         cpu_rel_addr = of_get_property(np, "cpu-release-addr", NULL);
  58
  59         if (cpu_rel_addr == NULL) {
  60                 printk(KERN_ERR "No cpu-release-addr for cpu %d\n", nr);
  61                 local_irq_restore(flags);
  62                 return;
  63         }
  64
  65         /* Map the spin table */
  66         bptr_vaddr = ioremap(*cpu_rel_addr, SIZE_BOOT_ENTRY);
  67
  68         out_be32(bptr_vaddr + BOOT_ENTRY_PIR, nr);
  69         out_be32(bptr_vaddr + BOOT_ENTRY_ADDR_LOWER, __pa(__early_start));
  70
  71         /* Wait a bit for the CPU to ack. */
  72         while ((__secondary_hold_acknowledge != nr) && (++n < 1000))
  73                 mdelay(1);
  74
  75         iounmap(bptr_vaddr);
  76
  77         local_irq_restore(flags);
  78
  79         pr_debug("waited %d msecs for CPU #%d.\n", n, nr);
  80 }
  81
  82 static void __init
  83 smp_85xx_setup_cpu(int cpu_nr)
  84 {
  85         mpic_setup_this_cpu();
  86
  87         /* Clear any pending timer interrupts */
  88         mtspr(SPRN_TSR, TSR_ENW | TSR_WIS | TSR_DIS | TSR_FIS);
  89
  90         /* Enable decrementer interrupt */
  91         mtspr(SPRN_TCR, TCR_DIE);
  92 }
  93
  94 struct smp_ops_t smp_85xx_ops = {
  95         .message_pass = smp_mpic_message_pass,
  96         .probe = smp_mpic_probe,
  97         .kick_cpu = smp_85xx_kick_cpu,
  98         .setup_cpu = smp_85xx_setup_cpu,
  99 };
 100
 101 void __init
 102 mpc85xx_smp_init(void)
 103 {
 104         smp_ops = &smp_85xx_ops;
 105 }