arch/mips/sgi-ip27/ip27-smp.c

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General
   3  * Public License.  See the file "COPYING" in the main directory of this
   4  * archive for more details.
   5  *
   6  * Copyright (C) 2000 - 2001 by Kanoj Sarcar (kanoj@sgi.com)
   7  * Copyright (C) 2000 - 2001 by Silicon Graphics, Inc.
   8  */
   9 #include <linux/init.h>
  10 #include <linux/sched.h>
  11 #include <linux/sched/task_stack.h>
  12 #include <linux/topology.h>
  13 #include <linux/nodemask.h>
  14
  15 #include <asm/page.h>
  16 #include <asm/processor.h>
  17 #include <asm/ptrace.h>
  18 #include <asm/sn/agent.h>
  19 #include <asm/sn/arch.h>
  20 #include <asm/sn/gda.h>
  21 #include <asm/sn/intr.h>
  22 #include <asm/sn/klconfig.h>
  23 #include <asm/sn/launch.h>
  24 #include <asm/sn/mapped_kernel.h>
  25 #include <asm/sn/types.h>
  26
  27 #include "ip27-common.h"
  28
  29 static int node_scan_cpus(nasid_t nasid, int highest)
  30 {
  31         static int cpus_found;
  32         lboard_t *brd;
  33         klcpu_t *acpu;
  34         cpuid_t cpuid;
  35
  36         brd = find_lboard((lboard_t *)KL_CONFIG_INFO(nasid), KLTYPE_IP27);
  37
  38         do {
  39                 acpu = (klcpu_t *)find_first_component(brd, KLSTRUCT_CPU);
  40                 while (acpu) {
  41                         cpuid = acpu->cpu_info.virtid;
  42                         /* Only let it join in if it's marked enabled */
  43                         if ((acpu->cpu_info.flags & KLINFO_ENABLE) &&
  44                             (cpus_found != NR_CPUS)) {
  45                                 if (cpuid > highest)
  46                                         highest = cpuid;
  47                                 set_cpu_possible(cpuid, true);
  48                                 cputonasid(cpus_found) = nasid;
  49                                 cputoslice(cpus_found) = acpu->cpu_info.physid;
  50                                 sn_cpu_info[cpus_found].p_speed =
  51                                                         acpu->cpu_speed;
  52                                 cpus_found++;
  53                         }
  54                         acpu = (klcpu_t *)find_component(brd, (klinfo_t *)acpu,
  55                                                                 KLSTRUCT_CPU);
  56                 }
  57                 brd = KLCF_NEXT(brd);
  58                 if (!brd)
  59                         break;
  60
  61                 brd = find_lboard(brd, KLTYPE_IP27);
  62         } while (brd);
  63
  64         return highest;
  65 }
  66
  67 void cpu_node_probe(void)
  68 {
  69         int i, highest = 0;
  70         gda_t *gdap = GDA;
  71
  72         nodes_clear(node_online_map);
  73         for (i = 0; i < MAX_NUMNODES; i++) {
  74                 nasid_t nasid = gdap->g_nasidtable[i];
  75                 if (nasid == INVALID_NASID)
  76                         break;
  77                 node_set_online(nasid);
  78                 highest = node_scan_cpus(nasid, highest);
  79         }
  80
  81         printk("Discovered %d cpus on %d nodes\n", highest + 1, num_online_nodes());
  82 }
  83
  84 static __init void intr_clear_all(nasid_t nasid)
  85 {
  86         int i;
  87
  88         REMOTE_HUB_S(nasid, PI_INT_MASK0_A, 0);
  89         REMOTE_HUB_S(nasid, PI_INT_MASK0_B, 0);
  90         REMOTE_HUB_S(nasid, PI_INT_MASK1_A, 0);
  91         REMOTE_HUB_S(nasid, PI_INT_MASK1_B, 0);
  92
  93         for (i = 0; i < 128; i++)
  94                 REMOTE_HUB_CLR_INTR(nasid, i);
  95 }
  96
  97 static void ip27_send_ipi_single(int destid, unsigned int action)
  98 {
  99         int irq;
 100
 101         switch (action) {
 102         case SMP_RESCHEDULE_YOURSELF:
 103                 irq = CPU_RESCHED_A_IRQ;
 104                 break;
 105         case SMP_CALL_FUNCTION:
 106                 irq = CPU_CALL_A_IRQ;
 107                 break;
 108         default:
 109                 panic("sendintr");
 110         }
 111
 112         irq += cputoslice(destid);
 113
 114         /*
 115          * Set the interrupt bit associated with the CPU we want to
 116          * send the interrupt to.
 117          */
 118         REMOTE_HUB_SEND_INTR(cpu_to_node(destid), irq);
 119 }
 120
 121 static void ip27_send_ipi_mask(const struct cpumask *mask, unsigned int action)
 122 {
 123         unsigned int i;
 124
 125         for_each_cpu(i, mask)
 126                 ip27_send_ipi_single(i, action);
 127 }
 128
 129 static void ip27_init_cpu(void)
 130 {
 131         per_cpu_init();
 132 }
 133
 134 static void ip27_smp_finish(void)
 135 {
 136         hub_rt_clock_event_init();
 137         local_irq_enable();
 138 }
 139
 140 /*
 141  * Launch a slave into smp_bootstrap().  It doesn't take an argument, and we
 142  * set sp to the kernel stack of the newly created idle process, gp to the proc
 143  * struct so that current_thread_info() will work.
 144  */
 145 static int ip27_boot_secondary(int cpu, struct task_struct *idle)
 146 {
 147         unsigned long gp = (unsigned long)task_thread_info(idle);
 148         unsigned long sp = __KSTK_TOS(idle);
 149
 150         LAUNCH_SLAVE(cputonasid(cpu), cputoslice(cpu),
 151                 (launch_proc_t)MAPPED_KERN_RW_TO_K0(smp_bootstrap),
 152                 0, (void *) sp, (void *) gp);
 153         return 0;
 154 }
 155
 156 static void __init ip27_smp_setup(void)
 157 {
 158         nasid_t nasid;
 159
 160         for_each_online_node(nasid) {
 161                 if (nasid == 0)
 162                         continue;
 163                 intr_clear_all(nasid);
 164         }
 165
 166         replicate_kernel_text();
 167
 168         /*
 169          * PROM sets up system, that boot cpu is always first CPU on nasid 0
 170          */
 171         cputonasid(0) = 0;
 172         cputoslice(0) = LOCAL_HUB_L(PI_CPU_NUM);
 173 }
 174
 175 static void __init ip27_prepare_cpus(unsigned int max_cpus)
 176 {
 177         /* We already did everything necessary earlier */
 178 }
 179
 180 const struct plat_smp_ops ip27_smp_ops = {
 181         .send_ipi_single        = ip27_send_ipi_single,
 182         .send_ipi_mask          = ip27_send_ipi_mask,
 183         .init_secondary         = ip27_init_cpu,
 184         .smp_finish             = ip27_smp_finish,
 185         .boot_secondary         = ip27_boot_secondary,
 186         .smp_setup              = ip27_smp_setup,
 187         .prepare_cpus           = ip27_prepare_cpus,
 188         .prepare_boot_cpu       = ip27_init_cpu,
 189 };