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 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         notify_cpu_starting(cpuid);
  76
  77         /* Get our local ticker going. */
  78         smp_setup_percpu_timer();
  79
  80         calibrate_delay();
  81         smp_store_cpu_info(cpuid);
  82
  83         local_flush_cache_all();
  84         local_flush_tlb_all();
  85
  86         /*
  87          * Unblock the master CPU _only_ when the scheduler state
  88          * of all secondary CPUs will be up-to-date, so after
  89          * the SMP initialization the master will be just allowed
  90          * to call the scheduler code.
  91          */
  92         /* Allow master to continue. */
  93         swap(&cpu_callin_map[cpuid], 1);
  94
  95         /* XXX: What's up with all the flushes? */
  96         local_flush_cache_all();
  97         local_flush_tlb_all();
  98
  99         cpu_probe();
 100
 101         /* Fix idle thread fields. */
 102         __asm__ __volatile__("ld [%0], %%g6\n\t"
 103                              : : "r" (&current_set[cpuid])
 104                              : "memory" /* paranoid */);
 105
 106         /* Attach to the address space of init_task. */
 107         atomic_inc(&init_mm.mm_count);
 108         current->active_mm = &init_mm;
 109
 110         while (!cpu_isset(cpuid, smp_commenced_mask))
 111                 mb();
 112
 113         local_irq_enable();
 114
 115         cpu_set(cpuid, cpu_online_map);
 116 }
 117
 118 /*
 119  *      Cycle through the processors asking the PROM to start each one.
 120  */
 121
 122 extern struct linux_prom_registers smp_penguin_ctable;
 123 extern unsigned long trapbase_cpu1[];
 124 extern unsigned long trapbase_cpu2[];
 125 extern unsigned long trapbase_cpu3[];
 126
 127 void __init smp4m_boot_cpus(void)
 128 {
 129         smp_setup_percpu_timer();
 130         local_flush_cache_all();
 131 }
 132
 133 int __cpuinit smp4m_boot_one_cpu(int i)
 134 {
 135         extern unsigned long sun4m_cpu_startup;
 136         unsigned long *entry = &sun4m_cpu_startup;
 137         struct task_struct *p;
 138         int timeout;
 139         int cpu_node;
 140
 141         cpu_find_by_mid(i, &cpu_node);
 142
 143         /* Cook up an idler for this guy. */
 144         p = fork_idle(i);
 145         current_set[i] = task_thread_info(p);
 146         /* See trampoline.S for details... */
 147         entry += ((i-1) * 3);
 148
 149         /*
 150          * Initialize the contexts table
 151          * Since the call to prom_startcpu() trashes the structure,
 152          * we need to re-initialize it for each cpu
 153          */
 154         smp_penguin_ctable.which_io = 0;
 155         smp_penguin_ctable.phys_addr = (unsigned int) srmmu_ctx_table_phys;
 156         smp_penguin_ctable.reg_size = 0;
 157
 158         /* whirrr, whirrr, whirrrrrrrrr... */
 159         printk("Starting CPU %d at %p\n", i, entry);
 160         local_flush_cache_all();
 161         prom_startcpu(cpu_node,
 162                       &smp_penguin_ctable, 0, (char *)entry);
 163
 164         /* wheee... it's going... */
 165         for(timeout = 0; timeout < 10000; timeout++) {
 166                 if(cpu_callin_map[i])
 167                         break;
 168                 udelay(200);
 169         }
 170
 171         if (!(cpu_callin_map[i])) {
 172                 printk("Processor %d is stuck.\n", i);
 173                 return -ENODEV;
 174         }
 175
 176         local_flush_cache_all();
 177         return 0;
 178 }
 179
 180 void __init smp4m_smp_done(void)
 181 {
 182         int i, first;
 183         int *prev;
 184
 185         /* setup cpu list for irq rotation */
 186         first = 0;
 187         prev = &first;
 188         for (i = 0; i < NR_CPUS; i++) {
 189                 if (cpu_online(i)) {
 190                         *prev = i;
 191                         prev = &cpu_data(i).next;
 192                 }
 193         }
 194         *prev = first;
 195         local_flush_cache_all();
 196
 197         /* Free unneeded trap tables */
 198         if (!cpu_isset(1, cpu_present_map)) {
 199                 ClearPageReserved(virt_to_page(trapbase_cpu1));
 200                 init_page_count(virt_to_page(trapbase_cpu1));
 201                 free_page((unsigned long)trapbase_cpu1);
 202                 totalram_pages++;
 203                 num_physpages++;
 204         }
 205         if (!cpu_isset(2, cpu_present_map)) {
 206                 ClearPageReserved(virt_to_page(trapbase_cpu2));
 207                 init_page_count(virt_to_page(trapbase_cpu2));
 208                 free_page((unsigned long)trapbase_cpu2);
 209                 totalram_pages++;
 210                 num_physpages++;
 211         }
 212         if (!cpu_isset(3, cpu_present_map)) {
 213                 ClearPageReserved(virt_to_page(trapbase_cpu3));
 214                 init_page_count(virt_to_page(trapbase_cpu3));
 215                 free_page((unsigned long)trapbase_cpu3);
 216                 totalram_pages++;
 217                 num_physpages++;
 218         }
 219
 220         /* Ok, they are spinning and ready to go. */
 221 }
 222
 223 /* At each hardware IRQ, we get this called to forward IRQ reception
 224  * to the next processor.  The caller must disable the IRQ level being
 225  * serviced globally so that there are no double interrupts received.
 226  *
 227  * XXX See sparc64 irq.c.
 228  */
 229 void smp4m_irq_rotate(int cpu)
 230 {
 231         int next = cpu_data(cpu).next;
 232         if (next != cpu)
 233                 set_irq_udt(next);
 234 }
 235
 236 static struct smp_funcall {
 237         smpfunc_t func;
 238         unsigned long arg1;
 239         unsigned long arg2;
 240         unsigned long arg3;
 241         unsigned long arg4;
 242         unsigned long arg5;
 243         unsigned long processors_in[SUN4M_NCPUS];  /* Set when ipi entered. */
 244         unsigned long processors_out[SUN4M_NCPUS]; /* Set when ipi exited. */
 245 } ccall_info;
 246
 247 static DEFINE_SPINLOCK(cross_call_lock);
 248
 249 /* Cross calls must be serialized, at least currently. */
 250 static void smp4m_cross_call(smpfunc_t func, cpumask_t mask, unsigned long arg1,
 251                              unsigned long arg2, unsigned long arg3,
 252                              unsigned long arg4)
 253 {
 254                 register int ncpus = SUN4M_NCPUS;
 255                 unsigned long flags;
 256
 257                 spin_lock_irqsave(&cross_call_lock, flags);
 258
 259                 /* Init function glue. */
 260                 ccall_info.func = func;
 261                 ccall_info.arg1 = arg1;
 262                 ccall_info.arg2 = arg2;
 263                 ccall_info.arg3 = arg3;
 264                 ccall_info.arg4 = arg4;
 265                 ccall_info.arg5 = 0;
 266
 267                 /* Init receive/complete mapping, plus fire the IPI's off. */
 268                 {
 269                         register int i;
 270
 271                         cpu_clear(smp_processor_id(), mask);
 272                         cpus_and(mask, cpu_online_map, mask);
 273                         for(i = 0; i < ncpus; i++) {
 274                                 if (cpu_isset(i, mask)) {
 275                                         ccall_info.processors_in[i] = 0;
 276                                         ccall_info.processors_out[i] = 0;
 277                                         set_cpu_int(i, IRQ_CROSS_CALL);
 278                                 } else {
 279                                         ccall_info.processors_in[i] = 1;
 280                                         ccall_info.processors_out[i] = 1;
 281                                 }
 282                         }
 283                 }
 284
 285                 {
 286                         register int i;
 287
 288                         i = 0;
 289                         do {
 290                                 if (!cpu_isset(i, mask))
 291                                         continue;
 292                                 while(!ccall_info.processors_in[i])
 293                                         barrier();
 294                         } while(++i < ncpus);
 295
 296                         i = 0;
 297                         do {
 298                                 if (!cpu_isset(i, mask))
 299                                         continue;
 300                                 while(!ccall_info.processors_out[i])
 301                                         barrier();
 302                         } while(++i < ncpus);
 303                 }
 304
 305                 spin_unlock_irqrestore(&cross_call_lock, flags);
 306 }
 307
 308 /* Running cross calls. */
 309 void smp4m_cross_call_irq(void)
 310 {
 311         int i = smp_processor_id();
 312
 313         ccall_info.processors_in[i] = 1;
 314         ccall_info.func(ccall_info.arg1, ccall_info.arg2, ccall_info.arg3,
 315                         ccall_info.arg4, ccall_info.arg5);
 316         ccall_info.processors_out[i] = 1;
 317 }
 318
 319 extern void sun4m_clear_profile_irq(int cpu);
 320
 321 void smp4m_percpu_timer_interrupt(struct pt_regs *regs)
 322 {
 323         struct pt_regs *old_regs;
 324         int cpu = smp_processor_id();
 325
 326         old_regs = set_irq_regs(regs);
 327
 328         sun4m_clear_profile_irq(cpu);
 329
 330         profile_tick(CPU_PROFILING);
 331
 332         if(!--prof_counter(cpu)) {
 333                 int user = user_mode(regs);
 334
 335                 irq_enter();
 336                 update_process_times(user);
 337                 irq_exit();
 338
 339                 prof_counter(cpu) = prof_multiplier(cpu);
 340         }
 341         set_irq_regs(old_regs);
 342 }
 343
 344 extern unsigned int lvl14_resolution;
 345
 346 static void __cpuinit smp_setup_percpu_timer(void)
 347 {
 348         int cpu = smp_processor_id();
 349
 350         prof_counter(cpu) = prof_multiplier(cpu) = 1;
 351         load_profile_irq(cpu, lvl14_resolution);
 352
 353         if(cpu == boot_cpu_id)
 354                 enable_pil_irq(14);
 355 }
 356
 357 static void __init smp4m_blackbox_id(unsigned *addr)
 358 {
 359         int rd = *addr & 0x3e000000;
 360         int rs1 = rd >> 11;
 361
 362         addr[0] = 0x81580000 | rd;              /* rd %tbr, reg */
 363         addr[1] = 0x8130200c | rd | rs1;        /* srl reg, 0xc, reg */
 364         addr[2] = 0x80082003 | rd | rs1;        /* and reg, 3, reg */
 365 }
 366
 367 static void __init smp4m_blackbox_current(unsigned *addr)
 368 {
 369         int rd = *addr & 0x3e000000;
 370         int rs1 = rd >> 11;
 371
 372         addr[0] = 0x81580000 | rd;              /* rd %tbr, reg */
 373         addr[2] = 0x8130200a | rd | rs1;        /* srl reg, 0xa, reg */
 374         addr[4] = 0x8008200c | rd | rs1;        /* and reg, 0xc, reg */
 375 }
 376
 377 void __init sun4m_init_smp(void)
 378 {
 379         BTFIXUPSET_BLACKBOX(hard_smp_processor_id, smp4m_blackbox_id);
 380         BTFIXUPSET_BLACKBOX(load_current, smp4m_blackbox_current);
 381         BTFIXUPSET_CALL(smp_cross_call, smp4m_cross_call, BTFIXUPCALL_NORM);
 382         BTFIXUPSET_CALL(__hard_smp_processor_id, __smp4m_processor_id, BTFIXUPCALL_NORM);
 383 }