arch/sparc/kernel/sun4m_smp.c

   1 /* sun4m_smp.c: Sparc SUN4M SMP support.
   2  *
   3  * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
   4  */
   5
   6 #include <asm/head.h>
   7
   8 #include <linux/kernel.h>
   9 #include <linux/sched.h>
  10 #include <linux/threads.h>
  11 #include <linux/smp.h>
  12 #include <linux/smp_lock.h>
  13 #include <linux/interrupt.h>
  14 #include <linux/kernel_stat.h>
  15 #include <linux/init.h>
  16 #include <linux/spinlock.h>
  17 #include <linux/mm.h>
  18 #include <linux/swap.h>
  19 #include <linux/profile.h>
  20 #include <asm/cacheflush.h>
  21 #include <asm/tlbflush.h>
  22
  23 #include <asm/ptrace.h>
  24 #include <asm/atomic.h>
  25
  26 #include <asm/delay.h>
  27 #include <asm/irq.h>
  28 #include <asm/page.h>
  29 #include <asm/pgalloc.h>
  30 #include <asm/pgtable.h>
  31 #include <asm/oplib.h>
  32 #include <asm/cpudata.h>
  33
  34 #define IRQ_RESCHEDULE          13
  35 #define IRQ_STOP_CPU            14
  36 #define IRQ_CROSS_CALL          15
  37
  38 extern ctxd_t *srmmu_ctx_table_phys;
  39
  40 extern void calibrate_delay(void);
  41
  42 extern volatile int smp_processors_ready;
  43 extern volatile unsigned long cpu_callin_map[NR_CPUS];
  44 extern unsigned char boot_cpu_id;
  45
  46 extern cpumask_t smp_commenced_mask;
  47
  48 extern int __smp4m_processor_id(void);
  49
  50 /*#define SMP_DEBUG*/
  51
  52 #ifdef SMP_DEBUG
  53 #define SMP_PRINTK(x)   printk x
  54 #else
  55 #define SMP_PRINTK(x)
  56 #endif
  57
  58 static inline unsigned long swap(volatile unsigned long *ptr, unsigned long val)
  59 {
  60         __asm__ __volatile__("swap [%1], %0\n\t" :
  61                              "=&r" (val), "=&r" (ptr) :
  62                              "0" (val), "1" (ptr));
  63         return val;
  64 }
  65
  66 static void smp_setup_percpu_timer(void);
  67 extern void cpu_probe(void);
  68
  69 void __init smp4m_callin(void)
  70 {
  71         int cpuid = hard_smp_processor_id();
  72
  73         local_flush_cache_all();
  74         local_flush_tlb_all();
  75
  76         /* Get our local ticker going. */
  77         smp_setup_percpu_timer();
  78
  79         calibrate_delay();
  80         smp_store_cpu_info(cpuid);
  81
  82         local_flush_cache_all();
  83         local_flush_tlb_all();
  84
  85         /*
  86          * Unblock the master CPU _only_ when the scheduler state
  87          * of all secondary CPUs will be up-to-date, so after
  88          * the SMP initialization the master will be just allowed
  89          * to call the scheduler code.
  90          */
  91         /* Allow master to continue. */
  92         swap(&cpu_callin_map[cpuid], 1);
  93
  94         /* XXX: What's up with all the flushes? */
  95         local_flush_cache_all();
  96         local_flush_tlb_all();
  97
  98         cpu_probe();
  99
 100         /* Fix idle thread fields. */
 101         __asm__ __volatile__("ld [%0], %%g6\n\t"
 102                              : : "r" (&current_set[cpuid])
 103                              : "memory" /* paranoid */);
 104
 105         /* Attach to the address space of init_task. */
 106         atomic_inc(&init_mm.mm_count);
 107         current->active_mm = &init_mm;
 108
 109         while (!cpu_isset(cpuid, smp_commenced_mask))
 110                 mb();
 111
 112         local_irq_enable();
 113
 114         cpu_set(cpuid, cpu_online_map);
 115         /* last one in gets all the interrupts (for testing) */
 116         set_irq_udt(boot_cpu_id);
 117 }
 118
 119 extern void init_IRQ(void);
 120 extern void cpu_panic(void);
 121
 122 /*
 123  *      Cycle through the processors asking the PROM to start each one.
 124  */
 125
 126 extern struct linux_prom_registers smp_penguin_ctable;
 127 extern unsigned long trapbase_cpu1[];
 128 extern unsigned long trapbase_cpu2[];
 129 extern unsigned long trapbase_cpu3[];
 130
 131 void __init smp4m_boot_cpus(void)
 132 {
 133         smp_setup_percpu_timer();
 134         local_flush_cache_all();
 135 }
 136
 137 int smp4m_boot_one_cpu(int i)
 138 {
 139         extern unsigned long sun4m_cpu_startup;
 140         unsigned long *entry = &sun4m_cpu_startup;
 141         struct task_struct *p;
 142         int timeout;
 143         int cpu_node;
 144
 145         cpu_find_by_mid(i, &cpu_node);
 146
 147         /* Cook up an idler for this guy. */
 148         p = fork_idle(i);
 149         current_set[i] = task_thread_info(p);
 150         /* See trampoline.S for details... */
 151         entry += ((i-1) * 3);
 152
 153         /*
 154          * Initialize the contexts table
 155          * Since the call to prom_startcpu() trashes the structure,
 156          * we need to re-initialize it for each cpu
 157          */
 158         smp_penguin_ctable.which_io = 0;
 159         smp_penguin_ctable.phys_addr = (unsigned int) srmmu_ctx_table_phys;
 160         smp_penguin_ctable.reg_size = 0;
 161
 162         /* whirrr, whirrr, whirrrrrrrrr... */
 163         printk("Starting CPU %d at %p\n", i, entry);
 164         local_flush_cache_all();
 165         prom_startcpu(cpu_node,
 166                       &smp_penguin_ctable, 0, (char *)entry);
 167
 168         /* wheee... it's going... */
 169         for(timeout = 0; timeout < 10000; timeout++) {
 170                 if(cpu_callin_map[i])
 171                         break;
 172                 udelay(200);
 173         }
 174
 175         if (!(cpu_callin_map[i])) {
 176                 printk("Processor %d is stuck.\n", i);
 177                 return -ENODEV;
 178         }
 179
 180         local_flush_cache_all();
 181         return 0;
 182 }
 183
 184 void __init smp4m_smp_done(void)
 185 {
 186         int i, first;
 187         int *prev;
 188
 189         /* setup cpu list for irq rotation */
 190         first = 0;
 191         prev = &first;
 192         for (i = 0; i < NR_CPUS; i++) {
 193                 if (cpu_online(i)) {
 194                         *prev = i;
 195                         prev = &cpu_data(i).next;
 196                 }
 197         }
 198         *prev = first;
 199         local_flush_cache_all();
 200
 201         /* Free unneeded trap tables */
 202         if (!cpu_isset(1, cpu_present_map)) {
 203                 ClearPageReserved(virt_to_page(trapbase_cpu1));
 204                 init_page_count(virt_to_page(trapbase_cpu1));
 205                 free_page((unsigned long)trapbase_cpu1);
 206                 totalram_pages++;
 207                 num_physpages++;
 208         }
 209         if (!cpu_isset(2, cpu_present_map)) {
 210                 ClearPageReserved(virt_to_page(trapbase_cpu2));
 211                 init_page_count(virt_to_page(trapbase_cpu2));
 212                 free_page((unsigned long)trapbase_cpu2);
 213                 totalram_pages++;
 214                 num_physpages++;
 215         }
 216         if (!cpu_isset(3, cpu_present_map)) {
 217                 ClearPageReserved(virt_to_page(trapbase_cpu3));
 218                 init_page_count(virt_to_page(trapbase_cpu3));
 219                 free_page((unsigned long)trapbase_cpu3);
 220                 totalram_pages++;
 221                 num_physpages++;
 222         }
 223
 224         /* Ok, they are spinning and ready to go. */
 225         smp_processors_ready = 1;
 226 }
 227
 228 /* At each hardware IRQ, we get this called to forward IRQ reception
 229  * to the next processor.  The caller must disable the IRQ level being
 230  * serviced globally so that there are no double interrupts received.
 231  *
 232  * XXX See sparc64 irq.c.
 233  */
 234 void smp4m_irq_rotate(int cpu)
 235 {
 236         int next = cpu_data(cpu).next;
 237         if (next != cpu)
 238                 set_irq_udt(next);
 239 }
 240
 241 /* Cross calls, in order to work efficiently and atomically do all
 242  * the message passing work themselves, only stopcpu and reschedule
 243  * messages come through here.
 244  */
 245 void smp4m_message_pass(int target, int msg, unsigned long data, int wait)
 246 {
 247         static unsigned long smp_cpu_in_msg[NR_CPUS];
 248         cpumask_t mask;
 249         int me = smp_processor_id();
 250         int irq, i;
 251
 252         if(msg == MSG_RESCHEDULE) {
 253                 irq = IRQ_RESCHEDULE;
 254
 255                 if(smp_cpu_in_msg[me])
 256                         return;
 257         } else if(msg == MSG_STOP_CPU) {
 258                 irq = IRQ_STOP_CPU;
 259         } else {
 260                 goto barf;
 261         }
 262
 263         smp_cpu_in_msg[me]++;
 264         if(target == MSG_ALL_BUT_SELF || target == MSG_ALL) {
 265                 mask = cpu_online_map;
 266                 if(target == MSG_ALL_BUT_SELF)
 267                         cpu_clear(me, mask);
 268                 for(i = 0; i < 4; i++) {
 269                         if (cpu_isset(i, mask))
 270                                 set_cpu_int(i, irq);
 271                 }
 272         } else {
 273                 set_cpu_int(target, irq);
 274         }
 275         smp_cpu_in_msg[me]--;
 276
 277         return;
 278 barf:
 279         printk("Yeeee, trying to send SMP msg(%d) on cpu %d\n", msg, me);
 280         panic("Bogon SMP message pass.");
 281 }
 282
 283 static struct smp_funcall {
 284         smpfunc_t func;
 285         unsigned long arg1;
 286         unsigned long arg2;
 287         unsigned long arg3;
 288         unsigned long arg4;
 289         unsigned long arg5;
 290         unsigned long processors_in[SUN4M_NCPUS];  /* Set when ipi entered. */
 291         unsigned long processors_out[SUN4M_NCPUS]; /* Set when ipi exited. */
 292 } ccall_info;
 293
 294 static DEFINE_SPINLOCK(cross_call_lock);
 295
 296 /* Cross calls must be serialized, at least currently. */
 297 void smp4m_cross_call(smpfunc_t func, unsigned long arg1, unsigned long arg2,
 298                     unsigned long arg3, unsigned long arg4, unsigned long arg5)
 299 {
 300                 register int ncpus = SUN4M_NCPUS;
 301                 unsigned long flags;
 302
 303                 spin_lock_irqsave(&cross_call_lock, flags);
 304
 305                 /* Init function glue. */
 306                 ccall_info.func = func;
 307                 ccall_info.arg1 = arg1;
 308                 ccall_info.arg2 = arg2;
 309                 ccall_info.arg3 = arg3;
 310                 ccall_info.arg4 = arg4;
 311                 ccall_info.arg5 = arg5;
 312
 313                 /* Init receive/complete mapping, plus fire the IPI's off. */
 314                 {
 315                         cpumask_t mask = cpu_online_map;
 316                         register int i;
 317
 318                         cpu_clear(smp_processor_id(), mask);
 319                         for(i = 0; i < ncpus; i++) {
 320                                 if (cpu_isset(i, mask)) {
 321                                         ccall_info.processors_in[i] = 0;
 322                                         ccall_info.processors_out[i] = 0;
 323                                         set_cpu_int(i, IRQ_CROSS_CALL);
 324                                 } else {
 325                                         ccall_info.processors_in[i] = 1;
 326                                         ccall_info.processors_out[i] = 1;
 327                                 }
 328                         }
 329                 }
 330
 331                 {
 332                         register int i;
 333
 334                         i = 0;
 335                         do {
 336                                 while(!ccall_info.processors_in[i])
 337                                         barrier();
 338                         } while(++i < ncpus);
 339
 340                         i = 0;
 341                         do {
 342                                 while(!ccall_info.processors_out[i])
 343                                         barrier();
 344                         } while(++i < ncpus);
 345                 }
 346
 347                 spin_unlock_irqrestore(&cross_call_lock, flags);
 348 }
 349
 350 /* Running cross calls. */
 351 void smp4m_cross_call_irq(void)
 352 {
 353         int i = smp_processor_id();
 354
 355         ccall_info.processors_in[i] = 1;
 356         ccall_info.func(ccall_info.arg1, ccall_info.arg2, ccall_info.arg3,
 357                         ccall_info.arg4, ccall_info.arg5);
 358         ccall_info.processors_out[i] = 1;
 359 }
 360
 361 void smp4m_percpu_timer_interrupt(struct pt_regs *regs)
 362 {
 363         int cpu = smp_processor_id();
 364
 365         clear_profile_irq(cpu);
 366
 367         profile_tick(CPU_PROFILING, regs);
 368
 369         if(!--prof_counter(cpu)) {
 370                 int user = user_mode(regs);
 371
 372                 irq_enter();
 373                 update_process_times(user);
 374                 irq_exit();
 375
 376                 prof_counter(cpu) = prof_multiplier(cpu);
 377         }
 378 }
 379
 380 extern unsigned int lvl14_resolution;
 381
 382 static void __init smp_setup_percpu_timer(void)
 383 {
 384         int cpu = smp_processor_id();
 385
 386         prof_counter(cpu) = prof_multiplier(cpu) = 1;
 387         load_profile_irq(cpu, lvl14_resolution);
 388
 389         if(cpu == boot_cpu_id)
 390                 enable_pil_irq(14);
 391 }
 392
 393 void __init smp4m_blackbox_id(unsigned *addr)
 394 {
 395         int rd = *addr & 0x3e000000;
 396         int rs1 = rd >> 11;
 397
 398         addr[0] = 0x81580000 | rd;              /* rd %tbr, reg */
 399         addr[1] = 0x8130200c | rd | rs1;        /* srl reg, 0xc, reg */
 400         addr[2] = 0x80082003 | rd | rs1;        /* and reg, 3, reg */
 401 }
 402
 403 void __init smp4m_blackbox_current(unsigned *addr)
 404 {
 405         int rd = *addr & 0x3e000000;
 406         int rs1 = rd >> 11;
 407
 408         addr[0] = 0x81580000 | rd;              /* rd %tbr, reg */
 409         addr[2] = 0x8130200a | rd | rs1;        /* srl reg, 0xa, reg */
 410         addr[4] = 0x8008200c | rd | rs1;        /* and reg, 3, reg */
 411 }
 412
 413 void __init sun4m_init_smp(void)
 414 {
 415         BTFIXUPSET_BLACKBOX(hard_smp_processor_id, smp4m_blackbox_id);
 416         BTFIXUPSET_BLACKBOX(load_current, smp4m_blackbox_current);
 417         BTFIXUPSET_CALL(smp_cross_call, smp4m_cross_call, BTFIXUPCALL_NORM);
 418         BTFIXUPSET_CALL(smp_message_pass, smp4m_message_pass, BTFIXUPCALL_NORM);
 419         BTFIXUPSET_CALL(__hard_smp_processor_id, __smp4m_processor_id, BTFIXUPCALL_NORM);
 420 }