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/interrupt.h>
  13 #include <linux/kernel_stat.h>
  14 #include <linux/init.h>
  15 #include <linux/spinlock.h>
  16 #include <linux/mm.h>
  17 #include <linux/swap.h>
  18 #include <linux/profile.h>
  19 #include <linux/delay.h>
  20
  21 #include <asm/cacheflush.h>
  22 #include <asm/tlbflush.h>
  23 #include <asm/irq_regs.h>
  24
  25 #include <asm/ptrace.h>
  26 #include <asm/atomic.h>
  27
  28 #include <asm/irq.h>
  29 #include <asm/page.h>
  30 #include <asm/pgalloc.h>
  31 #include <asm/pgtable.h>
  32 #include <asm/oplib.h>
  33 #include <asm/cpudata.h>
  34
  35 #include "irq.h"
  36
  37 #define IRQ_RESCHEDULE          13
  38 #define IRQ_STOP_CPU            14
  39 #define IRQ_CROSS_CALL          15
  40
  41 extern ctxd_t *srmmu_ctx_table_phys;
  42
  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 __cpuinit 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 }
 116
 117 /*
 118  *      Cycle through the processors asking the PROM to start each one.
 119  */
 120
 121 extern struct linux_prom_registers smp_penguin_ctable;
 122 extern unsigned long trapbase_cpu1[];
 123 extern unsigned long trapbase_cpu2[];
 124 extern unsigned long trapbase_cpu3[];
 125
 126 void __init smp4m_boot_cpus(void)
 127 {
 128         smp_setup_percpu_timer();
 129         local_flush_cache_all();
 130 }
 131
 132 int __cpuinit smp4m_boot_one_cpu(int i)
 133 {
 134         extern unsigned long sun4m_cpu_startup;
 135         unsigned long *entry = &sun4m_cpu_startup;
 136         struct task_struct *p;
 137         int timeout;
 138         int cpu_node;
 139
 140         cpu_find_by_mid(i, &cpu_node);
 141
 142         /* Cook up an idler for this guy. */
 143         p = fork_idle(i);
 144         current_set[i] = task_thread_info(p);
 145         /* See trampoline.S for details... */
 146         entry += ((i-1) * 3);
 147
 148         /*
 149          * Initialize the contexts table
 150          * Since the call to prom_startcpu() trashes the structure,
 151          * we need to re-initialize it for each cpu
 152          */
 153         smp_penguin_ctable.which_io = 0;
 154         smp_penguin_ctable.phys_addr = (unsigned int) srmmu_ctx_table_phys;
 155         smp_penguin_ctable.reg_size = 0;
 156
 157         /* whirrr, whirrr, whirrrrrrrrr... */
 158         printk("Starting CPU %d at %p\n", i, entry);
 159         local_flush_cache_all();
 160         prom_startcpu(cpu_node,
 161                       &smp_penguin_ctable, 0, (char *)entry);
 162
 163         /* wheee... it's going... */
 164         for(timeout = 0; timeout < 10000; timeout++) {
 165                 if(cpu_callin_map[i])
 166                         break;
 167                 udelay(200);
 168         }
 169
 170         if (!(cpu_callin_map[i])) {
 171                 printk("Processor %d is stuck.\n", i);
 172                 return -ENODEV;
 173         }
 174
 175         local_flush_cache_all();
 176         return 0;
 177 }
 178
 179 void __init smp4m_smp_done(void)
 180 {
 181         int i, first;
 182         int *prev;
 183
 184         /* setup cpu list for irq rotation */
 185         first = 0;
 186         prev = &first;
 187         for (i = 0; i < NR_CPUS; i++) {
 188                 if (cpu_online(i)) {
 189                         *prev = i;
 190                         prev = &cpu_data(i).next;
 191                 }
 192         }
 193         *prev = first;
 194         local_flush_cache_all();
 195
 196         /* Free unneeded trap tables */
 197         if (!cpu_isset(1, cpu_present_map)) {
 198                 ClearPageReserved(virt_to_page(trapbase_cpu1));
 199                 init_page_count(virt_to_page(trapbase_cpu1));
 200                 free_page((unsigned long)trapbase_cpu1);
 201                 totalram_pages++;
 202                 num_physpages++;
 203         }
 204         if (!cpu_isset(2, cpu_present_map)) {
 205                 ClearPageReserved(virt_to_page(trapbase_cpu2));
 206                 init_page_count(virt_to_page(trapbase_cpu2));
 207                 free_page((unsigned long)trapbase_cpu2);
 208                 totalram_pages++;
 209                 num_physpages++;
 210         }
 211         if (!cpu_isset(3, cpu_present_map)) {
 212                 ClearPageReserved(virt_to_page(trapbase_cpu3));
 213                 init_page_count(virt_to_page(trapbase_cpu3));
 214                 free_page((unsigned long)trapbase_cpu3);
 215                 totalram_pages++;
 216                 num_physpages++;
 217         }
 218
 219         /* Ok, they are spinning and ready to go. */
 220 }
 221
 222 /* At each hardware IRQ, we get this called to forward IRQ reception
 223  * to the next processor.  The caller must disable the IRQ level being
 224  * serviced globally so that there are no double interrupts received.
 225  *
 226  * XXX See sparc64 irq.c.
 227  */
 228 void smp4m_irq_rotate(int cpu)
 229 {
 230         int next = cpu_data(cpu).next;
 231         if (next != cpu)
 232                 set_irq_udt(next);
 233 }
 234
 235 /* Cross calls, in order to work efficiently and atomically do all
 236  * the message passing work themselves, only stopcpu and reschedule
 237  * messages come through here.
 238  */
 239 void smp4m_message_pass(int target, int msg, unsigned long data, int wait)
 240 {
 241         static unsigned long smp_cpu_in_msg[NR_CPUS];
 242         cpumask_t mask;
 243         int me = smp_processor_id();
 244         int irq, i;
 245
 246         if(msg == MSG_RESCHEDULE) {
 247                 irq = IRQ_RESCHEDULE;
 248
 249                 if(smp_cpu_in_msg[me])
 250                         return;
 251         } else if(msg == MSG_STOP_CPU) {
 252                 irq = IRQ_STOP_CPU;
 253         } else {
 254                 goto barf;
 255         }
 256
 257         smp_cpu_in_msg[me]++;
 258         if(target == MSG_ALL_BUT_SELF || target == MSG_ALL) {
 259                 mask = cpu_online_map;
 260                 if(target == MSG_ALL_BUT_SELF)
 261                         cpu_clear(me, mask);
 262                 for(i = 0; i < 4; i++) {
 263                         if (cpu_isset(i, mask))
 264                                 set_cpu_int(i, irq);
 265                 }
 266         } else {
 267                 set_cpu_int(target, irq);
 268         }
 269         smp_cpu_in_msg[me]--;
 270
 271         return;
 272 barf:
 273         printk("Yeeee, trying to send SMP msg(%d) on cpu %d\n", msg, me);
 274         panic("Bogon SMP message pass.");
 275 }
 276
 277 static struct smp_funcall {
 278         smpfunc_t func;
 279         unsigned long arg1;
 280         unsigned long arg2;
 281         unsigned long arg3;
 282         unsigned long arg4;
 283         unsigned long arg5;
 284         unsigned long processors_in[SUN4M_NCPUS];  /* Set when ipi entered. */
 285         unsigned long processors_out[SUN4M_NCPUS]; /* Set when ipi exited. */
 286 } ccall_info;
 287
 288 static DEFINE_SPINLOCK(cross_call_lock);
 289
 290 /* Cross calls must be serialized, at least currently. */
 291 void smp4m_cross_call(smpfunc_t func, unsigned long arg1, unsigned long arg2,
 292                     unsigned long arg3, unsigned long arg4, unsigned long arg5)
 293 {
 294                 register int ncpus = SUN4M_NCPUS;
 295                 unsigned long flags;
 296
 297                 spin_lock_irqsave(&cross_call_lock, flags);
 298
 299                 /* Init function glue. */
 300                 ccall_info.func = func;
 301                 ccall_info.arg1 = arg1;
 302                 ccall_info.arg2 = arg2;
 303                 ccall_info.arg3 = arg3;
 304                 ccall_info.arg4 = arg4;
 305                 ccall_info.arg5 = arg5;
 306
 307                 /* Init receive/complete mapping, plus fire the IPI's off. */
 308                 {
 309                         cpumask_t mask = cpu_online_map;
 310                         register int i;
 311
 312                         cpu_clear(smp_processor_id(), mask);
 313                         for(i = 0; i < ncpus; i++) {
 314                                 if (cpu_isset(i, mask)) {
 315                                         ccall_info.processors_in[i] = 0;
 316                                         ccall_info.processors_out[i] = 0;
 317                                         set_cpu_int(i, IRQ_CROSS_CALL);
 318                                 } else {
 319                                         ccall_info.processors_in[i] = 1;
 320                                         ccall_info.processors_out[i] = 1;
 321                                 }
 322                         }
 323                 }
 324
 325                 {
 326                         register int i;
 327
 328                         i = 0;
 329                         do {
 330                                 while(!ccall_info.processors_in[i])
 331                                         barrier();
 332                         } while(++i < ncpus);
 333
 334                         i = 0;
 335                         do {
 336                                 while(!ccall_info.processors_out[i])
 337                                         barrier();
 338                         } while(++i < ncpus);
 339                 }
 340
 341                 spin_unlock_irqrestore(&cross_call_lock, flags);
 342 }
 343
 344 /* Running cross calls. */
 345 void smp4m_cross_call_irq(void)
 346 {
 347         int i = smp_processor_id();
 348
 349         ccall_info.processors_in[i] = 1;
 350         ccall_info.func(ccall_info.arg1, ccall_info.arg2, ccall_info.arg3,
 351                         ccall_info.arg4, ccall_info.arg5);
 352         ccall_info.processors_out[i] = 1;
 353 }
 354
 355 void smp4m_percpu_timer_interrupt(struct pt_regs *regs)
 356 {
 357         struct pt_regs *old_regs;
 358         int cpu = smp_processor_id();
 359
 360         old_regs = set_irq_regs(regs);
 361
 362         clear_profile_irq(cpu);
 363
 364         profile_tick(CPU_PROFILING);
 365
 366         if(!--prof_counter(cpu)) {
 367                 int user = user_mode(regs);
 368
 369                 irq_enter();
 370                 update_process_times(user);
 371                 irq_exit();
 372
 373                 prof_counter(cpu) = prof_multiplier(cpu);
 374         }
 375         set_irq_regs(old_regs);
 376 }
 377
 378 extern unsigned int lvl14_resolution;
 379
 380 static void __init smp_setup_percpu_timer(void)
 381 {
 382         int cpu = smp_processor_id();
 383
 384         prof_counter(cpu) = prof_multiplier(cpu) = 1;
 385         load_profile_irq(cpu, lvl14_resolution);
 386
 387         if(cpu == boot_cpu_id)
 388                 enable_pil_irq(14);
 389 }
 390
 391 void __init smp4m_blackbox_id(unsigned *addr)
 392 {
 393         int rd = *addr & 0x3e000000;
 394         int rs1 = rd >> 11;
 395
 396         addr[0] = 0x81580000 | rd;              /* rd %tbr, reg */
 397         addr[1] = 0x8130200c | rd | rs1;        /* srl reg, 0xc, reg */
 398         addr[2] = 0x80082003 | rd | rs1;        /* and reg, 3, reg */
 399 }
 400
 401 void __init smp4m_blackbox_current(unsigned *addr)
 402 {
 403         int rd = *addr & 0x3e000000;
 404         int rs1 = rd >> 11;
 405
 406         addr[0] = 0x81580000 | rd;              /* rd %tbr, reg */
 407         addr[2] = 0x8130200a | rd | rs1;        /* srl reg, 0xa, reg */
 408         addr[4] = 0x8008200c | rd | rs1;        /* and reg, 0xc, reg */
 409 }
 410
 411 void __init sun4m_init_smp(void)
 412 {
 413         BTFIXUPSET_BLACKBOX(hard_smp_processor_id, smp4m_blackbox_id);
 414         BTFIXUPSET_BLACKBOX(load_current, smp4m_blackbox_current);
 415         BTFIXUPSET_CALL(smp_cross_call, smp4m_cross_call, BTFIXUPCALL_NORM);
 416         BTFIXUPSET_CALL(smp_message_pass, smp4m_message_pass, BTFIXUPCALL_NORM);
 417         BTFIXUPSET_CALL(__hard_smp_processor_id, __smp4m_processor_id, BTFIXUPCALL_NORM);
 418 }