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
  27 #include "platform.h"
  28
  29 #if defined(DEBUG)
  30 #define DBG udbg_printf
  31 #else
  32 #define DBG pr_debug
  33 #endif
  34
  35 static irqreturn_t ipi_function_handler(int irq, void *msg)
  36 {
  37         smp_message_recv((int)(long)msg);
  38         return IRQ_HANDLED;
  39 }
  40
  41 /**
  42   * ps3_ipi_virqs - a per cpu array of virqs for ipi use
  43   */
  44
  45 #define MSG_COUNT 4
  46 static DEFINE_PER_CPU(unsigned int, ps3_ipi_virqs[MSG_COUNT]);
  47
  48 static const char *names[MSG_COUNT] = {
  49         "ipi call",
  50         "ipi reschedule",
  51         "ipi migrate",
  52         "ipi debug brk"
  53 };
  54
  55 static void do_message_pass(int target, int msg)
  56 {
  57         int result;
  58         unsigned int virq;
  59
  60         if (msg >= MSG_COUNT) {
  61                 DBG("%s:%d: bad msg: %d\n", __func__, __LINE__, msg);
  62                 return;
  63         }
  64
  65         virq = per_cpu(ps3_ipi_virqs, target)[msg];
  66         result = ps3_send_event_locally(virq);
  67
  68         if (result)
  69                 DBG("%s:%d: ps3_send_event_locally(%d, %d) failed"
  70                         " (%d)\n", __func__, __LINE__, target, msg, result);
  71 }
  72
  73 static void ps3_smp_message_pass(int target, int msg)
  74 {
  75         int cpu;
  76
  77         if (target < NR_CPUS)
  78                 do_message_pass(target, msg);
  79         else if (target == MSG_ALL_BUT_SELF) {
  80                 for_each_online_cpu(cpu)
  81                         if (cpu != smp_processor_id())
  82                                 do_message_pass(cpu, msg);
  83         } else {
  84                 for_each_online_cpu(cpu)
  85                         do_message_pass(cpu, msg);
  86         }
  87 }
  88
  89 static int ps3_smp_probe(void)
  90 {
  91         return 2;
  92 }
  93
  94 static void __init ps3_smp_setup_cpu(int cpu)
  95 {
  96         int result;
  97         unsigned int *virqs = per_cpu(ps3_ipi_virqs, cpu);
  98         int i;
  99
 100         DBG(" -> %s:%d: (%d)\n", __func__, __LINE__, cpu);
 101
 102         /*
 103          * Check assumptions on ps3_ipi_virqs[] indexing. If this
 104          * check fails, then a different mapping of PPC_MSG_
 105          * to index needs to be setup.
 106          */
 107
 108         BUILD_BUG_ON(PPC_MSG_CALL_FUNCTION  != 0);
 109         BUILD_BUG_ON(PPC_MSG_RESCHEDULE     != 1);
 110         BUILD_BUG_ON(PPC_MSG_DEBUGGER_BREAK != 3);
 111
 112         for (i = 0; i < MSG_COUNT; i++) {
 113                 result = ps3_event_receive_port_setup(cpu, &virqs[i]);
 114
 115                 if (result)
 116                         continue;
 117
 118                 DBG("%s:%d: (%d, %d) => virq %u\n",
 119                         __func__, __LINE__, cpu, i, virqs[i]);
 120
 121                 result = request_irq(virqs[i], ipi_function_handler,
 122                         IRQF_DISABLED, names[i], (void*)(long)i);
 123
 124                 if (result)
 125                         virqs[i] = NO_IRQ;
 126         }
 127
 128         ps3_register_ipi_debug_brk(cpu, virqs[PPC_MSG_DEBUGGER_BREAK]);
 129
 130         DBG(" <- %s:%d: (%d)\n", __func__, __LINE__, cpu);
 131 }
 132
 133 void ps3_smp_cleanup_cpu(int cpu)
 134 {
 135         unsigned int *virqs = per_cpu(ps3_ipi_virqs, cpu);
 136         int i;
 137
 138         DBG(" -> %s:%d: (%d)\n", __func__, __LINE__, cpu);
 139
 140         for (i = 0; i < MSG_COUNT; i++) {
 141                 /* Can't call free_irq from interrupt context. */
 142                 ps3_event_receive_port_destroy(virqs[i]);
 143                 virqs[i] = NO_IRQ;
 144         }
 145
 146         DBG(" <- %s:%d: (%d)\n", __func__, __LINE__, cpu);
 147 }
 148
 149 static struct smp_ops_t ps3_smp_ops = {
 150         .probe          = ps3_smp_probe,
 151         .message_pass   = ps3_smp_message_pass,
 152         .kick_cpu       = smp_generic_kick_cpu,
 153         .setup_cpu      = ps3_smp_setup_cpu,
 154 };
 155
 156 void smp_init_ps3(void)
 157 {
 158         DBG(" -> %s\n", __func__);
 159         smp_ops = &ps3_smp_ops;
 160         DBG(" <- %s\n", __func__);
 161 }