arch/powerpc/platforms/ps3/smp.c

   1 /*
   2  *  PS3 SMP routines.
   3  *
   4  *  Copyright (C) 2006 Sony Computer Entertainment Inc.
   5  *  Copyright 2006 Sony Corp.
   6  *
   7  *  This program is free software; you can redistribute it and/or modify
   8  *  it under the terms of the GNU General Public License as published by
   9  *  the Free Software Foundation; version 2 of the License.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this program; if not, write to the Free Software
  18  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20
  21 #include <linux/kernel.h>
  22 #include <linux/smp.h>
  23
  24 #include <asm/machdep.h>
  25 #include <asm/udbg.h>
  26 #include <asm/ps3.h>
  27
  28 #include "platform.h"
  29
  30 #if defined(DEBUG)
  31 #define DBG(fmt...) udbg_printf(fmt)
  32 #else
  33 #define DBG(fmt...) do{if(0)printk(fmt);}while(0)
  34 #endif
  35
  36 static irqreturn_t ipi_function_handler(int irq, void *msg)
  37 {
  38         smp_message_recv((int)(long)msg);
  39         return IRQ_HANDLED;
  40 }
  41
  42 /**
  43   * virqs - a per cpu array of virqs for ipi use
  44   */
  45
  46 #define MSG_COUNT 4
  47 static DEFINE_PER_CPU(unsigned int, virqs[MSG_COUNT]);
  48
  49 static const char *names[MSG_COUNT] = {
  50         "ipi call",
  51         "ipi reschedule",
  52         "ipi migrate",
  53         "ipi debug brk"
  54 };
  55
  56 static void do_message_pass(int target, int msg)
  57 {
  58         int result;
  59         unsigned int virq;
  60
  61         if (msg >= MSG_COUNT) {
  62                 DBG("%s:%d: bad msg: %d\n", __func__, __LINE__, msg);
  63                 return;
  64         }
  65
  66         virq = per_cpu(virqs, target)[msg];
  67         result = ps3_send_event_locally(virq);
  68
  69         if (result)
  70                 DBG("%s:%d: ps3_send_event_locally(%d, %d) failed"
  71                         " (%d)\n", __func__, __LINE__, target, msg, result);
  72 }
  73
  74 static void ps3_smp_message_pass(int target, int msg)
  75 {
  76         int cpu;
  77
  78         if (target < NR_CPUS)
  79                 do_message_pass(target, msg);
  80         else if (target == MSG_ALL_BUT_SELF) {
  81                 for_each_online_cpu(cpu)
  82                         if (cpu != smp_processor_id())
  83                                 do_message_pass(cpu, msg);
  84         } else {
  85                 for_each_online_cpu(cpu)
  86                         do_message_pass(cpu, msg);
  87         }
  88 }
  89
  90 static int ps3_smp_probe(void)
  91 {
  92         return 2;
  93 }
  94
  95 static void __init ps3_smp_setup_cpu(int cpu)
  96 {
  97         int result;
  98         unsigned int *virqs = per_cpu(virqs, cpu);
  99         int i;
 100
 101         DBG(" -> %s:%d: (%d)\n", __func__, __LINE__, cpu);
 102
 103         /*
 104          * Check assumptions on virqs[] indexing. If this
 105          * check fails, then a different mapping of PPC_MSG_
 106          * to index needs to be setup.
 107          */
 108
 109         BUILD_BUG_ON(PPC_MSG_CALL_FUNCTION  != 0);
 110         BUILD_BUG_ON(PPC_MSG_RESCHEDULE     != 1);
 111         BUILD_BUG_ON(PPC_MSG_DEBUGGER_BREAK != 3);
 112
 113         for (i = 0; i < MSG_COUNT; i++) {
 114                 result = ps3_alloc_event_irq(cpu, &virqs[i]);
 115
 116                 if (result)
 117                         continue;
 118
 119                 DBG("%s:%d: (%d, %d) => virq %u\n",
 120                         __func__, __LINE__, cpu, i, virqs[i]);
 121
 122
 123                 request_irq(virqs[i], ipi_function_handler, IRQF_DISABLED,
 124                         names[i], (void*)(long)i);
 125         }
 126
 127         ps3_register_ipi_debug_brk(cpu, virqs[PPC_MSG_DEBUGGER_BREAK]);
 128
 129         DBG(" <- %s:%d: (%d)\n", __func__, __LINE__, cpu);
 130 }
 131
 132 void ps3_smp_cleanup_cpu(int cpu)
 133 {
 134         unsigned int *virqs = per_cpu(virqs, cpu);
 135         int i;
 136
 137         DBG(" -> %s:%d: (%d)\n", __func__, __LINE__, cpu);
 138         for (i = 0; i < MSG_COUNT; i++) {
 139                 ps3_free_event_irq(virqs[i]);
 140                 free_irq(virqs[i], (void*)(long)i);
 141                 virqs[i] = NO_IRQ;
 142         }
 143         DBG(" <- %s:%d: (%d)\n", __func__, __LINE__, cpu);
 144 }
 145
 146 static struct smp_ops_t ps3_smp_ops = {
 147         .probe          = ps3_smp_probe,
 148         .message_pass   = ps3_smp_message_pass,
 149         .kick_cpu       = smp_generic_kick_cpu,
 150         .setup_cpu      = ps3_smp_setup_cpu,
 151 };
 152
 153 void smp_init_ps3(void)
 154 {
 155         DBG(" -> %s\n", __func__);
 156         smp_ops = &ps3_smp_ops;
 157         DBG(" <- %s\n", __func__);
 158 }