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         set_cpu_online(cpuid, true);
 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
 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_each_online_cpu(i) {
 187                 *prev = i;
 188                 prev = &cpu_data(i).next;
 189         }
 190         *prev = first;
 191         local_flush_cache_all();
 192
 193         /* Ok, they are spinning and ready to go. */
 194 }
 195
 196 /* At each hardware IRQ, we get this called to forward IRQ reception
 197  * to the next processor.  The caller must disable the IRQ level being
 198  * serviced globally so that there are no double interrupts received.
 199  *
 200  * XXX See sparc64 irq.c.
 201  */
 202 void smp4m_irq_rotate(int cpu)
 203 {
 204         int next = cpu_data(cpu).next;
 205         if (next != cpu)
 206                 set_irq_udt(next);
 207 }
 208
 209 static struct smp_funcall {
 210         smpfunc_t func;
 211         unsigned long arg1;
 212         unsigned long arg2;
 213         unsigned long arg3;
 214         unsigned long arg4;
 215         unsigned long arg5;
 216         unsigned long processors_in[SUN4M_NCPUS];  /* Set when ipi entered. */
 217         unsigned long processors_out[SUN4M_NCPUS]; /* Set when ipi exited. */
 218 } ccall_info;
 219
 220 static DEFINE_SPINLOCK(cross_call_lock);
 221
 222 /* Cross calls must be serialized, at least currently. */
 223 static void smp4m_cross_call(smpfunc_t func, cpumask_t mask, unsigned long arg1,
 224                              unsigned long arg2, unsigned long arg3,
 225                              unsigned long arg4)
 226 {
 227                 register int ncpus = SUN4M_NCPUS;
 228                 unsigned long flags;
 229
 230                 spin_lock_irqsave(&cross_call_lock, flags);
 231
 232                 /* Init function glue. */
 233                 ccall_info.func = func;
 234                 ccall_info.arg1 = arg1;
 235                 ccall_info.arg2 = arg2;
 236                 ccall_info.arg3 = arg3;
 237                 ccall_info.arg4 = arg4;
 238                 ccall_info.arg5 = 0;
 239
 240                 /* Init receive/complete mapping, plus fire the IPI's off. */
 241                 {
 242                         register int i;
 243
 244                         cpu_clear(smp_processor_id(), mask);
 245                         cpus_and(mask, cpu_online_map, mask);
 246                         for(i = 0; i < ncpus; i++) {
 247                                 if (cpu_isset(i, mask)) {
 248                                         ccall_info.processors_in[i] = 0;
 249                                         ccall_info.processors_out[i] = 0;
 250                                         set_cpu_int(i, IRQ_CROSS_CALL);
 251                                 } else {
 252                                         ccall_info.processors_in[i] = 1;
 253                                         ccall_info.processors_out[i] = 1;
 254                                 }
 255                         }
 256                 }
 257
 258                 {
 259                         register int i;
 260
 261                         i = 0;
 262                         do {
 263                                 if (!cpu_isset(i, mask))
 264                                         continue;
 265                                 while(!ccall_info.processors_in[i])
 266                                         barrier();
 267                         } while(++i < ncpus);
 268
 269                         i = 0;
 270                         do {
 271                                 if (!cpu_isset(i, mask))
 272                                         continue;
 273                                 while(!ccall_info.processors_out[i])
 274                                         barrier();
 275                         } while(++i < ncpus);
 276                 }
 277
 278                 spin_unlock_irqrestore(&cross_call_lock, flags);
 279 }
 280
 281 /* Running cross calls. */
 282 void smp4m_cross_call_irq(void)
 283 {
 284         int i = smp_processor_id();
 285
 286         ccall_info.processors_in[i] = 1;
 287         ccall_info.func(ccall_info.arg1, ccall_info.arg2, ccall_info.arg3,
 288                         ccall_info.arg4, ccall_info.arg5);
 289         ccall_info.processors_out[i] = 1;
 290 }
 291
 292 extern void sun4m_clear_profile_irq(int cpu);
 293
 294 void smp4m_percpu_timer_interrupt(struct pt_regs *regs)
 295 {
 296         struct pt_regs *old_regs;
 297         int cpu = smp_processor_id();
 298
 299         old_regs = set_irq_regs(regs);
 300
 301         sun4m_clear_profile_irq(cpu);
 302
 303         profile_tick(CPU_PROFILING);
 304
 305         if(!--prof_counter(cpu)) {
 306                 int user = user_mode(regs);
 307
 308                 irq_enter();
 309                 update_process_times(user);
 310                 irq_exit();
 311
 312                 prof_counter(cpu) = prof_multiplier(cpu);
 313         }
 314         set_irq_regs(old_regs);
 315 }
 316
 317 extern unsigned int lvl14_resolution;
 318
 319 static void __cpuinit smp_setup_percpu_timer(void)
 320 {
 321         int cpu = smp_processor_id();
 322
 323         prof_counter(cpu) = prof_multiplier(cpu) = 1;
 324         load_profile_irq(cpu, lvl14_resolution);
 325
 326         if(cpu == boot_cpu_id)
 327                 enable_pil_irq(14);
 328 }
 329
 330 static void __init smp4m_blackbox_id(unsigned *addr)
 331 {
 332         int rd = *addr & 0x3e000000;
 333         int rs1 = rd >> 11;
 334
 335         addr[0] = 0x81580000 | rd;              /* rd %tbr, reg */
 336         addr[1] = 0x8130200c | rd | rs1;        /* srl reg, 0xc, reg */
 337         addr[2] = 0x80082003 | rd | rs1;        /* and reg, 3, reg */
 338 }
 339
 340 static void __init smp4m_blackbox_current(unsigned *addr)
 341 {
 342         int rd = *addr & 0x3e000000;
 343         int rs1 = rd >> 11;
 344
 345         addr[0] = 0x81580000 | rd;              /* rd %tbr, reg */
 346         addr[2] = 0x8130200a | rd | rs1;        /* srl reg, 0xa, reg */
 347         addr[4] = 0x8008200c | rd | rs1;        /* and reg, 0xc, reg */
 348 }
 349
 350 void __init sun4m_init_smp(void)
 351 {
 352         BTFIXUPSET_BLACKBOX(hard_smp_processor_id, smp4m_blackbox_id);
 353         BTFIXUPSET_BLACKBOX(load_current, smp4m_blackbox_current);
 354         BTFIXUPSET_CALL(smp_cross_call, smp4m_cross_call, BTFIXUPCALL_NORM);
 355         BTFIXUPSET_CALL(__hard_smp_processor_id, __smp4m_processor_id, BTFIXUPCALL_NORM);
 356 }