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 #include <linux/cpu.h>
  21
  22 #include <asm/cacheflush.h>
  23 #include <asm/tlbflush.h>
  24 #include <asm/irq_regs.h>
  25
  26 #include <asm/ptrace.h>
  27 #include <asm/atomic.h>
  28
  29 #include <asm/irq.h>
  30 #include <asm/page.h>
  31 #include <asm/pgalloc.h>
  32 #include <asm/pgtable.h>
  33 #include <asm/oplib.h>
  34 #include <asm/cpudata.h>
  35
  36 #include "irq.h"
  37
  38 #define IRQ_CROSS_CALL          15
  39
  40 extern ctxd_t *srmmu_ctx_table_phys;
  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
  58 swap_ulong(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         notify_cpu_starting(cpuid);
  77
  78         /* Get our local ticker going. */
  79         smp_setup_percpu_timer();
  80
  81         calibrate_delay();
  82         smp_store_cpu_info(cpuid);
  83
  84         local_flush_cache_all();
  85         local_flush_tlb_all();
  86
  87         /*
  88          * Unblock the master CPU _only_ when the scheduler state
  89          * of all secondary CPUs will be up-to-date, so after
  90          * the SMP initialization the master will be just allowed
  91          * to call the scheduler code.
  92          */
  93         /* Allow master to continue. */
  94         swap_ulong(&cpu_callin_map[cpuid], 1);
  95
  96         /* XXX: What's up with all the flushes? */
  97         local_flush_cache_all();
  98         local_flush_tlb_all();
  99
 100         cpu_probe();
 101
 102         /* Fix idle thread fields. */
 103         __asm__ __volatile__("ld [%0], %%g6\n\t"
 104                              : : "r" (&current_set[cpuid])
 105                              : "memory" /* paranoid */);
 106
 107         /* Attach to the address space of init_task. */
 108         atomic_inc(&init_mm.mm_count);
 109         current->active_mm = &init_mm;
 110
 111         while (!cpu_isset(cpuid, smp_commenced_mask))
 112                 mb();
 113
 114         local_irq_enable();
 115
 116         cpu_set(cpuid, cpu_online_map);
 117 }
 118
 119 /*
 120  *      Cycle through the processors asking the PROM to start each one.
 121  */
 122
 123 extern struct linux_prom_registers smp_penguin_ctable;
 124 extern unsigned long trapbase_cpu1[];
 125 extern unsigned long trapbase_cpu2[];
 126 extern unsigned long trapbase_cpu3[];
 127
 128 void __init smp4m_boot_cpus(void)
 129 {
 130         smp_setup_percpu_timer();
 131         local_flush_cache_all();
 132 }
 133
 134 int __cpuinit smp4m_boot_one_cpu(int i)
 135 {
 136         extern unsigned long sun4m_cpu_startup;
 137         unsigned long *entry = &sun4m_cpu_startup;
 138         struct task_struct *p;
 139         int timeout;
 140         int cpu_node;
 141
 142         cpu_find_by_mid(i, &cpu_node);
 143
 144         /* Cook up an idler for this guy. */
 145         p = fork_idle(i);
 146         current_set[i] = task_thread_info(p);
 147         /* See trampoline.S for details... */
 148         entry += ((i-1) * 3);
 149
 150         /*
 151          * Initialize the contexts table
 152          * Since the call to prom_startcpu() trashes the structure,
 153          * we need to re-initialize it for each cpu
 154          */
 155         smp_penguin_ctable.which_io = 0;
 156         smp_penguin_ctable.phys_addr = (unsigned int) srmmu_ctx_table_phys;
 157         smp_penguin_ctable.reg_size = 0;
 158
 159         /* whirrr, whirrr, whirrrrrrrrr... */
 160         printk("Starting CPU %d at %p\n", i, entry);
 161         local_flush_cache_all();
 162         prom_startcpu(cpu_node,
 163                       &smp_penguin_ctable, 0, (char *)entry);
 164
 165         /* wheee... it's going... */
 166         for(timeout = 0; timeout < 10000; timeout++) {
 167                 if(cpu_callin_map[i])
 168                         break;
 169                 udelay(200);
 170         }
 171
 172         if (!(cpu_callin_map[i])) {
 173                 printk("Processor %d is stuck.\n", i);
 174                 return -ENODEV;
 175         }
 176
 177         local_flush_cache_all();
 178         return 0;
 179 }
 180
 181 void __init smp4m_smp_done(void)
 182 {
 183         int i, first;
 184         int *prev;
 185
 186         /* setup cpu list for irq rotation */
 187         first = 0;
 188         prev = &first;
 189         for (i = 0; i < NR_CPUS; i++) {
 190                 if (cpu_online(i)) {
 191                         *prev = i;
 192                         prev = &cpu_data(i).next;
 193                 }
 194         }
 195         *prev = first;
 196         local_flush_cache_all();
 197
 198         /* Free unneeded trap tables */
 199         if (!cpu_isset(1, cpu_present_map)) {
 200                 ClearPageReserved(virt_to_page(trapbase_cpu1));
 201                 init_page_count(virt_to_page(trapbase_cpu1));
 202                 free_page((unsigned long)trapbase_cpu1);
 203                 totalram_pages++;
 204                 num_physpages++;
 205         }
 206         if (!cpu_isset(2, cpu_present_map)) {
 207                 ClearPageReserved(virt_to_page(trapbase_cpu2));
 208                 init_page_count(virt_to_page(trapbase_cpu2));
 209                 free_page((unsigned long)trapbase_cpu2);
 210                 totalram_pages++;
 211                 num_physpages++;
 212         }
 213         if (!cpu_isset(3, cpu_present_map)) {
 214                 ClearPageReserved(virt_to_page(trapbase_cpu3));
 215                 init_page_count(virt_to_page(trapbase_cpu3));
 216                 free_page((unsigned long)trapbase_cpu3);
 217                 totalram_pages++;
 218                 num_physpages++;
 219         }
 220
 221         /* Ok, they are spinning and ready to go. */
 222 }
 223
 224 /* At each hardware IRQ, we get this called to forward IRQ reception
 225  * to the next processor.  The caller must disable the IRQ level being
 226  * serviced globally so that there are no double interrupts received.
 227  *
 228  * XXX See sparc64 irq.c.
 229  */
 230 void smp4m_irq_rotate(int cpu)
 231 {
 232         int next = cpu_data(cpu).next;
 233         if (next != cpu)
 234                 set_irq_udt(next);
 235 }
 236
 237 static struct smp_funcall {
 238         smpfunc_t func;
 239         unsigned long arg1;
 240         unsigned long arg2;
 241         unsigned long arg3;
 242         unsigned long arg4;
 243         unsigned long arg5;
 244         unsigned long processors_in[SUN4M_NCPUS];  /* Set when ipi entered. */
 245         unsigned long processors_out[SUN4M_NCPUS]; /* Set when ipi exited. */
 246 } ccall_info;
 247
 248 static DEFINE_SPINLOCK(cross_call_lock);
 249
 250 /* Cross calls must be serialized, at least currently. */
 251 static void smp4m_cross_call(smpfunc_t func, cpumask_t mask, unsigned long arg1,
 252                              unsigned long arg2, unsigned long arg3,
 253                              unsigned long arg4)
 254 {
 255                 register int ncpus = SUN4M_NCPUS;
 256                 unsigned long flags;
 257
 258                 spin_lock_irqsave(&cross_call_lock, flags);
 259
 260                 /* Init function glue. */
 261                 ccall_info.func = func;
 262                 ccall_info.arg1 = arg1;
 263                 ccall_info.arg2 = arg2;
 264                 ccall_info.arg3 = arg3;
 265                 ccall_info.arg4 = arg4;
 266                 ccall_info.arg5 = 0;
 267
 268                 /* Init receive/complete mapping, plus fire the IPI's off. */
 269                 {
 270                         register int i;
 271
 272                         cpu_clear(smp_processor_id(), mask);
 273                         cpus_and(mask, cpu_online_map, mask);
 274                         for(i = 0; i < ncpus; i++) {
 275                                 if (cpu_isset(i, mask)) {
 276                                         ccall_info.processors_in[i] = 0;
 277                                         ccall_info.processors_out[i] = 0;
 278                                         set_cpu_int(i, IRQ_CROSS_CALL);
 279                                 } else {
 280                                         ccall_info.processors_in[i] = 1;
 281                                         ccall_info.processors_out[i] = 1;
 282                                 }
 283                         }
 284                 }
 285
 286                 {
 287                         register int i;
 288
 289                         i = 0;
 290                         do {
 291                                 if (!cpu_isset(i, mask))
 292                                         continue;
 293                                 while(!ccall_info.processors_in[i])
 294                                         barrier();
 295                         } while(++i < ncpus);
 296
 297                         i = 0;
 298                         do {
 299                                 if (!cpu_isset(i, mask))
 300                                         continue;
 301                                 while(!ccall_info.processors_out[i])
 302                                         barrier();
 303                         } while(++i < ncpus);
 304                 }
 305
 306                 spin_unlock_irqrestore(&cross_call_lock, flags);
 307 }
 308
 309 /* Running cross calls. */
 310 void smp4m_cross_call_irq(void)
 311 {
 312         int i = smp_processor_id();
 313
 314         ccall_info.processors_in[i] = 1;
 315         ccall_info.func(ccall_info.arg1, ccall_info.arg2, ccall_info.arg3,
 316                         ccall_info.arg4, ccall_info.arg5);
 317         ccall_info.processors_out[i] = 1;
 318 }
 319
 320 extern void sun4m_clear_profile_irq(int cpu);
 321
 322 void smp4m_percpu_timer_interrupt(struct pt_regs *regs)
 323 {
 324         struct pt_regs *old_regs;
 325         int cpu = smp_processor_id();
 326
 327         old_regs = set_irq_regs(regs);
 328
 329         sun4m_clear_profile_irq(cpu);
 330
 331         profile_tick(CPU_PROFILING);
 332
 333         if(!--prof_counter(cpu)) {
 334                 int user = user_mode(regs);
 335
 336                 irq_enter();
 337                 update_process_times(user);
 338                 irq_exit();
 339
 340                 prof_counter(cpu) = prof_multiplier(cpu);
 341         }
 342         set_irq_regs(old_regs);
 343 }
 344
 345 extern unsigned int lvl14_resolution;
 346
 347 static void __cpuinit smp_setup_percpu_timer(void)
 348 {
 349         int cpu = smp_processor_id();
 350
 351         prof_counter(cpu) = prof_multiplier(cpu) = 1;
 352         load_profile_irq(cpu, lvl14_resolution);
 353
 354         if(cpu == boot_cpu_id)
 355                 enable_pil_irq(14);
 356 }
 357
 358 static void __init smp4m_blackbox_id(unsigned *addr)
 359 {
 360         int rd = *addr & 0x3e000000;
 361         int rs1 = rd >> 11;
 362
 363         addr[0] = 0x81580000 | rd;              /* rd %tbr, reg */
 364         addr[1] = 0x8130200c | rd | rs1;        /* srl reg, 0xc, reg */
 365         addr[2] = 0x80082003 | rd | rs1;        /* and reg, 3, reg */
 366 }
 367
 368 static void __init smp4m_blackbox_current(unsigned *addr)
 369 {
 370         int rd = *addr & 0x3e000000;
 371         int rs1 = rd >> 11;
 372
 373         addr[0] = 0x81580000 | rd;              /* rd %tbr, reg */
 374         addr[2] = 0x8130200a | rd | rs1;        /* srl reg, 0xa, reg */
 375         addr[4] = 0x8008200c | rd | rs1;        /* and reg, 0xc, reg */
 376 }
 377
 378 void __init sun4m_init_smp(void)
 379 {
 380         BTFIXUPSET_BLACKBOX(hard_smp_processor_id, smp4m_blackbox_id);
 381         BTFIXUPSET_BLACKBOX(load_current, smp4m_blackbox_current);
 382         BTFIXUPSET_CALL(smp_cross_call, smp4m_cross_call, BTFIXUPCALL_NORM);
 383         BTFIXUPSET_CALL(__hard_smp_processor_id, __smp4m_processor_id, BTFIXUPCALL_NORM);
 384 }