arch/sparc/kernel/sun4d_smp.c

   1 /* Sparc SS1000/SC2000 SMP support.
   2  *
   3  * Copyright (C) 1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
   4  *
   5  * Based on sun4m's smp.c, which is:
   6  * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
   7  */
   8
   9 #include <linux/clockchips.h>
  10 #include <linux/interrupt.h>
  11 #include <linux/profile.h>
  12 #include <linux/delay.h>
  13 #include <linux/sched/mm.h>
  14 #include <linux/cpu.h>
  15
  16 #include <asm/cacheflush.h>
  17 #include <asm/switch_to.h>
  18 #include <asm/tlbflush.h>
  19 #include <asm/timer.h>
  20 #include <asm/oplib.h>
  21 #include <asm/sbi.h>
  22 #include <asm/mmu.h>
  23
  24 #include "kernel.h"
  25 #include "irq.h"
  26
  27 #define IRQ_CROSS_CALL          15
  28
  29 static volatile int smp_processors_ready;
  30 static int smp_highest_cpu;
  31
  32 static inline unsigned long sun4d_swap(volatile unsigned long *ptr, unsigned long val)
  33 {
  34         __asm__ __volatile__("swap [%1], %0\n\t" :
  35                              "=&r" (val), "=&r" (ptr) :
  36                              "0" (val), "1" (ptr));
  37         return val;
  38 }
  39
  40 static void smp4d_ipi_init(void);
  41
  42 static unsigned char cpu_leds[32];
  43
  44 static inline void show_leds(int cpuid)
  45 {
  46         cpuid &= 0x1e;
  47         __asm__ __volatile__ ("stba %0, [%1] %2" : :
  48                               "r" ((cpu_leds[cpuid] << 4) | cpu_leds[cpuid+1]),
  49                               "r" (ECSR_BASE(cpuid) | BB_LEDS),
  50                               "i" (ASI_M_CTL));
  51 }
  52
  53 void sun4d_cpu_pre_starting(void *arg)
  54 {
  55         int cpuid = hard_smp_processor_id();
  56
  57         /* Show we are alive */
  58         cpu_leds[cpuid] = 0x6;
  59         show_leds(cpuid);
  60
  61         /* Enable level15 interrupt, disable level14 interrupt for now */
  62         cc_set_imsk((cc_get_imsk() & ~0x8000) | 0x4000);
  63 }
  64
  65 void sun4d_cpu_pre_online(void *arg)
  66 {
  67         unsigned long flags;
  68         int cpuid;
  69
  70         cpuid = hard_smp_processor_id();
  71
  72         /* Unblock the master CPU _only_ when the scheduler state
  73          * of all secondary CPUs will be up-to-date, so after
  74          * the SMP initialization the master will be just allowed
  75          * to call the scheduler code.
  76          */
  77         sun4d_swap((unsigned long *)&cpu_callin_map[cpuid], 1);
  78         local_ops->cache_all();
  79         local_ops->tlb_all();
  80
  81         while ((unsigned long)current_set[cpuid] < PAGE_OFFSET)
  82                 barrier();
  83
  84         while (current_set[cpuid]->cpu != cpuid)
  85                 barrier();
  86
  87         /* Fix idle thread fields. */
  88         __asm__ __volatile__("ld [%0], %%g6\n\t"
  89                              : : "r" (&current_set[cpuid])
  90                              : "memory" /* paranoid */);
  91
  92         cpu_leds[cpuid] = 0x9;
  93         show_leds(cpuid);
  94
  95         /* Attach to the address space of init_task. */
  96         mmgrab(&init_mm);
  97         current->active_mm = &init_mm;
  98
  99         local_ops->cache_all();
 100         local_ops->tlb_all();
 101
 102         while (!cpumask_test_cpu(cpuid, &smp_commenced_mask))
 103                 barrier();
 104
 105         spin_lock_irqsave(&sun4d_imsk_lock, flags);
 106         cc_set_imsk(cc_get_imsk() & ~0x4000); /* Allow PIL 14 as well */
 107         spin_unlock_irqrestore(&sun4d_imsk_lock, flags);
 108 }
 109
 110 /*
 111  *      Cycle through the processors asking the PROM to start each one.
 112  */
 113 void __init smp4d_boot_cpus(void)
 114 {
 115         smp4d_ipi_init();
 116         if (boot_cpu_id)
 117                 current_set[0] = NULL;
 118         local_ops->cache_all();
 119 }
 120
 121 int smp4d_boot_one_cpu(int i, struct task_struct *idle)
 122 {
 123         unsigned long *entry = &sun4d_cpu_startup;
 124         int timeout;
 125         int cpu_node;
 126
 127         cpu_find_by_instance(i, &cpu_node, NULL);
 128         current_set[i] = task_thread_info(idle);
 129         /*
 130          * Initialize the contexts table
 131          * Since the call to prom_startcpu() trashes the structure,
 132          * we need to re-initialize it for each cpu
 133          */
 134         smp_penguin_ctable.which_io = 0;
 135         smp_penguin_ctable.phys_addr = (unsigned int) srmmu_ctx_table_phys;
 136         smp_penguin_ctable.reg_size = 0;
 137
 138         /* whirrr, whirrr, whirrrrrrrrr... */
 139         printk(KERN_INFO "Starting CPU %d at %p\n", i, entry);
 140         local_ops->cache_all();
 141         prom_startcpu(cpu_node,
 142                       &smp_penguin_ctable, 0, (char *)entry);
 143
 144         printk(KERN_INFO "prom_startcpu returned :)\n");
 145
 146         /* wheee... it's going... */
 147         for (timeout = 0; timeout < 10000; timeout++) {
 148                 if (cpu_callin_map[i])
 149                         break;
 150                 udelay(200);
 151         }
 152
 153         if (!(cpu_callin_map[i])) {
 154                 printk(KERN_ERR "Processor %d is stuck.\n", i);
 155                 return -ENODEV;
 156
 157         }
 158         local_ops->cache_all();
 159         return 0;
 160 }
 161
 162 void __init smp4d_smp_done(void)
 163 {
 164         int i, first;
 165         int *prev;
 166
 167         /* setup cpu list for irq rotation */
 168         first = 0;
 169         prev = &first;
 170         for_each_online_cpu(i) {
 171                 *prev = i;
 172                 prev = &cpu_data(i).next;
 173         }
 174         *prev = first;
 175         local_ops->cache_all();
 176
 177         /* Ok, they are spinning and ready to go. */
 178         smp_processors_ready = 1;
 179         sun4d_distribute_irqs();
 180 }
 181
 182 /* Memory structure giving interrupt handler information about IPI generated */
 183 struct sun4d_ipi_work {
 184         int single;
 185         int msk;
 186         int resched;
 187 };
 188
 189 static DEFINE_PER_CPU_SHARED_ALIGNED(struct sun4d_ipi_work, sun4d_ipi_work);
 190
 191 /* Initialize IPIs on the SUN4D SMP machine */
 192 static void __init smp4d_ipi_init(void)
 193 {
 194         int cpu;
 195         struct sun4d_ipi_work *work;
 196
 197         printk(KERN_INFO "smp4d: setup IPI at IRQ %d\n", SUN4D_IPI_IRQ);
 198
 199         for_each_possible_cpu(cpu) {
 200                 work = &per_cpu(sun4d_ipi_work, cpu);
 201                 work->single = work->msk = work->resched = 0;
 202         }
 203 }
 204
 205 void sun4d_ipi_interrupt(void)
 206 {
 207         struct sun4d_ipi_work *work = this_cpu_ptr(&sun4d_ipi_work);
 208
 209         if (work->single) {
 210                 work->single = 0;
 211                 smp_call_function_single_interrupt();
 212         }
 213         if (work->msk) {
 214                 work->msk = 0;
 215                 smp_call_function_interrupt();
 216         }
 217         if (work->resched) {
 218                 work->resched = 0;
 219                 smp_resched_interrupt();
 220         }
 221 }
 222
 223 /* +-------+-------------+-----------+------------------------------------+
 224  * | bcast |  devid      |   sid     |              levels mask           |
 225  * +-------+-------------+-----------+------------------------------------+
 226  *  31      30         23 22       15 14                                 0
 227  */
 228 #define IGEN_MESSAGE(bcast, devid, sid, levels) \
 229         (((bcast) << 31) | ((devid) << 23) | ((sid) << 15) | (levels))
 230
 231 static void sun4d_send_ipi(int cpu, int level)
 232 {
 233         cc_set_igen(IGEN_MESSAGE(0, cpu << 3, 6 + ((level >> 1) & 7), 1 << (level - 1)));
 234 }
 235
 236 static void sun4d_ipi_single(int cpu)
 237 {
 238         struct sun4d_ipi_work *work = &per_cpu(sun4d_ipi_work, cpu);
 239
 240         /* Mark work */
 241         work->single = 1;
 242
 243         /* Generate IRQ on the CPU */
 244         sun4d_send_ipi(cpu, SUN4D_IPI_IRQ);
 245 }
 246
 247 static void sun4d_ipi_mask_one(int cpu)
 248 {
 249         struct sun4d_ipi_work *work = &per_cpu(sun4d_ipi_work, cpu);
 250
 251         /* Mark work */
 252         work->msk = 1;
 253
 254         /* Generate IRQ on the CPU */
 255         sun4d_send_ipi(cpu, SUN4D_IPI_IRQ);
 256 }
 257
 258 static void sun4d_ipi_resched(int cpu)
 259 {
 260         struct sun4d_ipi_work *work = &per_cpu(sun4d_ipi_work, cpu);
 261
 262         /* Mark work */
 263         work->resched = 1;
 264
 265         /* Generate IRQ on the CPU (any IRQ will cause resched) */
 266         sun4d_send_ipi(cpu, SUN4D_IPI_IRQ);
 267 }
 268
 269 static struct smp_funcall {
 270         smpfunc_t func;
 271         unsigned long arg1;
 272         unsigned long arg2;
 273         unsigned long arg3;
 274         unsigned long arg4;
 275         unsigned long arg5;
 276         unsigned char processors_in[NR_CPUS];  /* Set when ipi entered. */
 277         unsigned char processors_out[NR_CPUS]; /* Set when ipi exited. */
 278 } ccall_info __attribute__((aligned(8)));
 279
 280 static DEFINE_SPINLOCK(cross_call_lock);
 281
 282 /* Cross calls must be serialized, at least currently. */
 283 static void sun4d_cross_call(smpfunc_t func, cpumask_t mask, unsigned long arg1,
 284                              unsigned long arg2, unsigned long arg3,
 285                              unsigned long arg4)
 286 {
 287         if (smp_processors_ready) {
 288                 register int high = smp_highest_cpu;
 289                 unsigned long flags;
 290
 291                 spin_lock_irqsave(&cross_call_lock, flags);
 292
 293                 {
 294                         /*
 295                          * If you make changes here, make sure
 296                          * gcc generates proper code...
 297                          */
 298                         register smpfunc_t f asm("i0") = func;
 299                         register unsigned long a1 asm("i1") = arg1;
 300                         register unsigned long a2 asm("i2") = arg2;
 301                         register unsigned long a3 asm("i3") = arg3;
 302                         register unsigned long a4 asm("i4") = arg4;
 303                         register unsigned long a5 asm("i5") = 0;
 304
 305                         __asm__ __volatile__(
 306                                 "std %0, [%6]\n\t"
 307                                 "std %2, [%6 + 8]\n\t"
 308                                 "std %4, [%6 + 16]\n\t" : :
 309                                 "r"(f), "r"(a1), "r"(a2), "r"(a3), "r"(a4), "r"(a5),
 310                                 "r" (&ccall_info.func));
 311                 }
 312
 313                 /* Init receive/complete mapping, plus fire the IPI's off. */
 314                 {
 315                         register int i;
 316
 317                         cpumask_clear_cpu(smp_processor_id(), &mask);
 318                         cpumask_and(&mask, cpu_online_mask, &mask);
 319                         for (i = 0; i <= high; i++) {
 320                                 if (cpumask_test_cpu(i, &mask)) {
 321                                         ccall_info.processors_in[i] = 0;
 322                                         ccall_info.processors_out[i] = 0;
 323                                         sun4d_send_ipi(i, IRQ_CROSS_CALL);
 324                                 }
 325                         }
 326                 }
 327
 328                 {
 329                         register int i;
 330
 331                         i = 0;
 332                         do {
 333                                 if (!cpumask_test_cpu(i, &mask))
 334                                         continue;
 335                                 while (!ccall_info.processors_in[i])
 336                                         barrier();
 337                         } while (++i <= high);
 338
 339                         i = 0;
 340                         do {
 341                                 if (!cpumask_test_cpu(i, &mask))
 342                                         continue;
 343                                 while (!ccall_info.processors_out[i])
 344                                         barrier();
 345                         } while (++i <= high);
 346                 }
 347
 348                 spin_unlock_irqrestore(&cross_call_lock, flags);
 349         }
 350 }
 351
 352 /* Running cross calls. */
 353 void smp4d_cross_call_irq(void)
 354 {
 355         int i = hard_smp_processor_id();
 356
 357         ccall_info.processors_in[i] = 1;
 358         ccall_info.func(ccall_info.arg1, ccall_info.arg2, ccall_info.arg3,
 359                         ccall_info.arg4, ccall_info.arg5);
 360         ccall_info.processors_out[i] = 1;
 361 }
 362
 363 void smp4d_percpu_timer_interrupt(struct pt_regs *regs)
 364 {
 365         struct pt_regs *old_regs;
 366         int cpu = hard_smp_processor_id();
 367         struct clock_event_device *ce;
 368         static int cpu_tick[NR_CPUS];
 369         static char led_mask[] = { 0xe, 0xd, 0xb, 0x7, 0xb, 0xd };
 370
 371         old_regs = set_irq_regs(regs);
 372         bw_get_prof_limit(cpu);
 373         bw_clear_intr_mask(0, 1);       /* INTR_TABLE[0] & 1 is Profile IRQ */
 374
 375         cpu_tick[cpu]++;
 376         if (!(cpu_tick[cpu] & 15)) {
 377                 if (cpu_tick[cpu] == 0x60)
 378                         cpu_tick[cpu] = 0;
 379                 cpu_leds[cpu] = led_mask[cpu_tick[cpu] >> 4];
 380                 show_leds(cpu);
 381         }
 382
 383         ce = &per_cpu(sparc32_clockevent, cpu);
 384
 385         irq_enter();
 386         ce->event_handler(ce);
 387         irq_exit();
 388
 389         set_irq_regs(old_regs);
 390 }
 391
 392 static const struct sparc32_ipi_ops sun4d_ipi_ops = {
 393         .cross_call = sun4d_cross_call,
 394         .resched    = sun4d_ipi_resched,
 395         .single     = sun4d_ipi_single,
 396         .mask_one   = sun4d_ipi_mask_one,
 397 };
 398
 399 void __init sun4d_init_smp(void)
 400 {
 401         int i;
 402
 403         /* Patch ipi15 trap table */
 404         t_nmi[1] = t_nmi[1] + (linux_trap_ipi15_sun4d - linux_trap_ipi15_sun4m);
 405
 406         sparc32_ipi_ops = &sun4d_ipi_ops;
 407
 408         for (i = 0; i < NR_CPUS; i++) {
 409                 ccall_info.processors_in[i] = 1;
 410                 ccall_info.processors_out[i] = 1;
 411         }
 412 }