arch/sparc/kernel/smp_32.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /* smp.c: Sparc SMP support.
   3  *
   4  * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
   5  * Copyright (C) 1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
   6  * Copyright (C) 2004 Keith M Wesolowski (wesolows@foobazco.org)
   7  */
   8
   9 #include <asm/head.h>
  10
  11 #include <linux/kernel.h>
  12 #include <linux/sched.h>
  13 #include <linux/threads.h>
  14 #include <linux/smp.h>
  15 #include <linux/interrupt.h>
  16 #include <linux/kernel_stat.h>
  17 #include <linux/init.h>
  18 #include <linux/spinlock.h>
  19 #include <linux/mm.h>
  20 #include <linux/fs.h>
  21 #include <linux/seq_file.h>
  22 #include <linux/cache.h>
  23 #include <linux/delay.h>
  24 #include <linux/profile.h>
  25 #include <linux/cpu.h>
  26
  27 #include <asm/ptrace.h>
  28 #include <linux/atomic.h>
  29
  30 #include <asm/irq.h>
  31 #include <asm/page.h>
  32 #include <asm/pgalloc.h>
  33 #include <asm/pgtable.h>
  34 #include <asm/oplib.h>
  35 #include <asm/cacheflush.h>
  36 #include <asm/tlbflush.h>
  37 #include <asm/cpudata.h>
  38 #include <asm/timer.h>
  39 #include <asm/leon.h>
  40
  41 #include "kernel.h"
  42 #include "irq.h"
  43
  44 volatile unsigned long cpu_callin_map[NR_CPUS] = {0,};
  45
  46 cpumask_t smp_commenced_mask = CPU_MASK_NONE;
  47
  48 const struct sparc32_ipi_ops *sparc32_ipi_ops;
  49
  50 /* The only guaranteed locking primitive available on all Sparc
  51  * processors is 'ldstub [%reg + immediate], %dest_reg' which atomically
  52  * places the current byte at the effective address into dest_reg and
  53  * places 0xff there afterwards.  Pretty lame locking primitive
  54  * compared to the Alpha and the Intel no?  Most Sparcs have 'swap'
  55  * instruction which is much better...
  56  */
  57
  58 void smp_store_cpu_info(int id)
  59 {
  60         int cpu_node;
  61         int mid;
  62
  63         cpu_data(id).udelay_val = loops_per_jiffy;
  64
  65         cpu_find_by_mid(id, &cpu_node);
  66         cpu_data(id).clock_tick = prom_getintdefault(cpu_node,
  67                                                      "clock-frequency", 0);
  68         cpu_data(id).prom_node = cpu_node;
  69         mid = cpu_get_hwmid(cpu_node);
  70
  71         if (mid < 0) {
  72                 printk(KERN_NOTICE "No MID found for CPU%d at node 0x%08x", id, cpu_node);
  73                 mid = 0;
  74         }
  75         cpu_data(id).mid = mid;
  76 }
  77
  78 void __init smp_cpus_done(unsigned int max_cpus)
  79 {
  80         unsigned long bogosum = 0;
  81         int cpu, num = 0;
  82
  83         for_each_online_cpu(cpu) {
  84                 num++;
  85                 bogosum += cpu_data(cpu).udelay_val;
  86         }
  87
  88         printk("Total of %d processors activated (%lu.%02lu BogoMIPS).\n",
  89                 num, bogosum/(500000/HZ),
  90                 (bogosum/(5000/HZ))%100);
  91
  92         switch(sparc_cpu_model) {
  93         case sun4m:
  94                 smp4m_smp_done();
  95                 break;
  96         case sun4d:
  97                 smp4d_smp_done();
  98                 break;
  99         case sparc_leon:
 100                 leon_smp_done();
 101                 break;
 102         case sun4e:
 103                 printk("SUN4E\n");
 104                 BUG();
 105                 break;
 106         case sun4u:
 107                 printk("SUN4U\n");
 108                 BUG();
 109                 break;
 110         default:
 111                 printk("UNKNOWN!\n");
 112                 BUG();
 113                 break;
 114         }
 115 }
 116
 117 void cpu_panic(void)
 118 {
 119         printk("CPU[%d]: Returns from cpu_idle!\n", smp_processor_id());
 120         panic("SMP bolixed\n");
 121 }
 122
 123 struct linux_prom_registers smp_penguin_ctable = { 0 };
 124
 125 void smp_send_reschedule(int cpu)
 126 {
 127         /*
 128          * CPU model dependent way of implementing IPI generation targeting
 129          * a single CPU. The trap handler needs only to do trap entry/return
 130          * to call schedule.
 131          */
 132         sparc32_ipi_ops->resched(cpu);
 133 }
 134
 135 void smp_send_stop(void)
 136 {
 137 }
 138
 139 void arch_send_call_function_single_ipi(int cpu)
 140 {
 141         /* trigger one IPI single call on one CPU */
 142         sparc32_ipi_ops->single(cpu);
 143 }
 144
 145 void arch_send_call_function_ipi_mask(const struct cpumask *mask)
 146 {
 147         int cpu;
 148
 149         /* trigger IPI mask call on each CPU */
 150         for_each_cpu(cpu, mask)
 151                 sparc32_ipi_ops->mask_one(cpu);
 152 }
 153
 154 void smp_resched_interrupt(void)
 155 {
 156         irq_enter();
 157         scheduler_ipi();
 158         local_cpu_data().irq_resched_count++;
 159         irq_exit();
 160         /* re-schedule routine called by interrupt return code. */
 161 }
 162
 163 void smp_call_function_single_interrupt(void)
 164 {
 165         irq_enter();
 166         generic_smp_call_function_single_interrupt();
 167         local_cpu_data().irq_call_count++;
 168         irq_exit();
 169 }
 170
 171 void smp_call_function_interrupt(void)
 172 {
 173         irq_enter();
 174         generic_smp_call_function_interrupt();
 175         local_cpu_data().irq_call_count++;
 176         irq_exit();
 177 }
 178
 179 int setup_profiling_timer(unsigned int multiplier)
 180 {
 181         return -EINVAL;
 182 }
 183
 184 void __init smp_prepare_cpus(unsigned int max_cpus)
 185 {
 186         int i, cpuid, extra;
 187
 188         printk("Entering SMP Mode...\n");
 189
 190         extra = 0;
 191         for (i = 0; !cpu_find_by_instance(i, NULL, &cpuid); i++) {
 192                 if (cpuid >= NR_CPUS)
 193                         extra++;
 194         }
 195         /* i = number of cpus */
 196         if (extra && max_cpus > i - extra)
 197                 printk("Warning: NR_CPUS is too low to start all cpus\n");
 198
 199         smp_store_cpu_info(boot_cpu_id);
 200
 201         switch(sparc_cpu_model) {
 202         case sun4m:
 203                 smp4m_boot_cpus();
 204                 break;
 205         case sun4d:
 206                 smp4d_boot_cpus();
 207                 break;
 208         case sparc_leon:
 209                 leon_boot_cpus();
 210                 break;
 211         case sun4e:
 212                 printk("SUN4E\n");
 213                 BUG();
 214                 break;
 215         case sun4u:
 216                 printk("SUN4U\n");
 217                 BUG();
 218                 break;
 219         default:
 220                 printk("UNKNOWN!\n");
 221                 BUG();
 222                 break;
 223         }
 224 }
 225
 226 /* Set this up early so that things like the scheduler can init
 227  * properly.  We use the same cpu mask for both the present and
 228  * possible cpu map.
 229  */
 230 void __init smp_setup_cpu_possible_map(void)
 231 {
 232         int instance, mid;
 233
 234         instance = 0;
 235         while (!cpu_find_by_instance(instance, NULL, &mid)) {
 236                 if (mid < NR_CPUS) {
 237                         set_cpu_possible(mid, true);
 238                         set_cpu_present(mid, true);
 239                 }
 240                 instance++;
 241         }
 242 }
 243
 244 void __init smp_prepare_boot_cpu(void)
 245 {
 246         int cpuid = hard_smp_processor_id();
 247
 248         if (cpuid >= NR_CPUS) {
 249                 prom_printf("Serious problem, boot cpu id >= NR_CPUS\n");
 250                 prom_halt();
 251         }
 252         if (cpuid != 0)
 253                 printk("boot cpu id != 0, this could work but is untested\n");
 254
 255         current_thread_info()->cpu = cpuid;
 256         set_cpu_online(cpuid, true);
 257         set_cpu_possible(cpuid, true);
 258 }
 259
 260 int __cpu_up(unsigned int cpu, struct task_struct *tidle)
 261 {
 262         int ret=0;
 263
 264         switch(sparc_cpu_model) {
 265         case sun4m:
 266                 ret = smp4m_boot_one_cpu(cpu, tidle);
 267                 break;
 268         case sun4d:
 269                 ret = smp4d_boot_one_cpu(cpu, tidle);
 270                 break;
 271         case sparc_leon:
 272                 ret = leon_boot_one_cpu(cpu, tidle);
 273                 break;
 274         case sun4e:
 275                 printk("SUN4E\n");
 276                 BUG();
 277                 break;
 278         case sun4u:
 279                 printk("SUN4U\n");
 280                 BUG();
 281                 break;
 282         default:
 283                 printk("UNKNOWN!\n");
 284                 BUG();
 285                 break;
 286         }
 287
 288         if (!ret) {
 289                 cpumask_set_cpu(cpu, &smp_commenced_mask);
 290                 while (!cpu_online(cpu))
 291                         mb();
 292         }
 293         return ret;
 294 }
 295
 296 static void arch_cpu_pre_starting(void *arg)
 297 {
 298         local_ops->cache_all();
 299         local_ops->tlb_all();
 300
 301         switch(sparc_cpu_model) {
 302         case sun4m:
 303                 sun4m_cpu_pre_starting(arg);
 304                 break;
 305         case sun4d:
 306                 sun4d_cpu_pre_starting(arg);
 307                 break;
 308         case sparc_leon:
 309                 leon_cpu_pre_starting(arg);
 310                 break;
 311         default:
 312                 BUG();
 313         }
 314 }
 315
 316 static void arch_cpu_pre_online(void *arg)
 317 {
 318         unsigned int cpuid = hard_smp_processor_id();
 319
 320         register_percpu_ce(cpuid);
 321
 322         calibrate_delay();
 323         smp_store_cpu_info(cpuid);
 324
 325         local_ops->cache_all();
 326         local_ops->tlb_all();
 327
 328         switch(sparc_cpu_model) {
 329         case sun4m:
 330                 sun4m_cpu_pre_online(arg);
 331                 break;
 332         case sun4d:
 333                 sun4d_cpu_pre_online(arg);
 334                 break;
 335         case sparc_leon:
 336                 leon_cpu_pre_online(arg);
 337                 break;
 338         default:
 339                 BUG();
 340         }
 341 }
 342
 343 static void sparc_start_secondary(void *arg)
 344 {
 345         unsigned int cpu;
 346
 347         /*
 348          * SMP booting is extremely fragile in some architectures. So run
 349          * the cpu initialization code first before anything else.
 350          */
 351         arch_cpu_pre_starting(arg);
 352
 353         preempt_disable();
 354         cpu = smp_processor_id();
 355
 356         notify_cpu_starting(cpu);
 357         arch_cpu_pre_online(arg);
 358
 359         /* Set the CPU in the cpu_online_mask */
 360         set_cpu_online(cpu, true);
 361
 362         /* Enable local interrupts now */
 363         local_irq_enable();
 364
 365         wmb();
 366         cpu_startup_entry(CPUHP_AP_ONLINE_IDLE);
 367
 368         /* We should never reach here! */
 369         BUG();
 370 }
 371
 372 void smp_callin(void)
 373 {
 374         sparc_start_secondary(NULL);
 375 }
 376
 377 void smp_bogo(struct seq_file *m)
 378 {
 379         int i;
 380
 381         for_each_online_cpu(i) {
 382                 seq_printf(m,
 383                            "Cpu%dBogo\t: %lu.%02lu\n",
 384                            i,
 385                            cpu_data(i).udelay_val/(500000/HZ),
 386                            (cpu_data(i).udelay_val/(5000/HZ))%100);
 387         }
 388 }
 389
 390 void smp_info(struct seq_file *m)
 391 {
 392         int i;
 393
 394         seq_printf(m, "State:\n");
 395         for_each_online_cpu(i)
 396                 seq_printf(m, "CPU%d\t\t: online\n", i);
 397 }