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