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 #include <asm/dbell.h>
  25
  26 #include <sysdev/fsl_soc.h>
  27
  28 extern volatile unsigned long __secondary_hold_acknowledge;
  29 extern void __early_start(void);
  30
  31 #define BOOT_ENTRY_ADDR_UPPER   0
  32 #define BOOT_ENTRY_ADDR_LOWER   1
  33 #define BOOT_ENTRY_R3_UPPER     2
  34 #define BOOT_ENTRY_R3_LOWER     3
  35 #define BOOT_ENTRY_RESV         4
  36 #define BOOT_ENTRY_PIR          5
  37 #define BOOT_ENTRY_R6_UPPER     6
  38 #define BOOT_ENTRY_R6_LOWER     7
  39 #define NUM_BOOT_ENTRY          8
  40 #define SIZE_BOOT_ENTRY         (NUM_BOOT_ENTRY * sizeof(u32))
  41
  42 static void __init
  43 smp_85xx_kick_cpu(int nr)
  44 {
  45         unsigned long flags;
  46         const u64 *cpu_rel_addr;
  47         __iomem u32 *bptr_vaddr;
  48         struct device_node *np;
  49         int n = 0;
  50
  51         WARN_ON (nr < 0 || nr >= NR_CPUS);
  52
  53         pr_debug("smp_85xx_kick_cpu: kick CPU #%d\n", nr);
  54
  55         np = of_get_cpu_node(nr, NULL);
  56         cpu_rel_addr = of_get_property(np, "cpu-release-addr", NULL);
  57
  58         if (cpu_rel_addr == NULL) {
  59                 printk(KERN_ERR "No cpu-release-addr for cpu %d\n", nr);
  60                 return;
  61         }
  62
  63         /* Map the spin table */
  64         bptr_vaddr = ioremap(*cpu_rel_addr, SIZE_BOOT_ENTRY);
  65
  66         local_irq_save(flags);
  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         local_irq_restore(flags);
  76
  77         iounmap(bptr_vaddr);
  78
  79         pr_debug("waited %d msecs for CPU #%d.\n", n, nr);
  80 }
  81
  82 static void __init
  83 smp_85xx_basic_setup(int cpu_nr)
  84 {
  85         /* Clear any pending timer interrupts */
  86         mtspr(SPRN_TSR, TSR_ENW | TSR_WIS | TSR_DIS | TSR_FIS);
  87
  88         /* Enable decrementer interrupt */
  89         mtspr(SPRN_TCR, TCR_DIE);
  90 }
  91
  92 static void __init
  93 smp_85xx_setup_cpu(int cpu_nr)
  94 {
  95         mpic_setup_this_cpu();
  96
  97         smp_85xx_basic_setup(cpu_nr);
  98 }
  99
 100 struct smp_ops_t smp_85xx_ops = {
 101         .kick_cpu = smp_85xx_kick_cpu,
 102 };
 103
 104 static int __init smp_dummy_probe(void)
 105 {
 106         return NR_CPUS;
 107 }
 108
 109 void __init mpc85xx_smp_init(void)
 110 {
 111         struct device_node *np;
 112
 113         smp_85xx_ops.message_pass = NULL;
 114
 115         np = of_find_node_by_type(NULL, "open-pic");
 116         if (np) {
 117                 smp_85xx_ops.probe = smp_mpic_probe;
 118                 smp_85xx_ops.setup_cpu = smp_85xx_setup_cpu;
 119                 smp_85xx_ops.message_pass = smp_mpic_message_pass;
 120         } else {
 121                 smp_85xx_ops.probe = smp_dummy_probe;
 122                 smp_85xx_ops.setup_cpu = smp_85xx_basic_setup;
 123         }
 124
 125         if (cpu_has_feature(CPU_FTR_DBELL))
 126                 smp_85xx_ops.message_pass = smp_dbell_message_pass;
 127
 128         BUG_ON(!smp_85xx_ops.message_pass);
 129
 130         smp_ops = &smp_85xx_ops;
 131 }