arch/sparc/kernel/sun4m_smp.c

   1 /*
   2  *  sun4m SMP support.
   3  *
   4  * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
   5  */
   6
   7 #include <linux/interrupt.h>
   8 #include <linux/profile.h>
   9 #include <linux/delay.h>
  10 #include <linux/cpu.h>
  11
  12 #include <asm/cacheflush.h>
  13 #include <asm/switch_to.h>
  14 #include <asm/tlbflush.h>
  15
  16 #include "irq.h"
  17 #include "kernel.h"
  18
  19 #define IRQ_IPI_SINGLE          12
  20 #define IRQ_IPI_MASK            13
  21 #define IRQ_IPI_RESCHED         14
  22 #define IRQ_CROSS_CALL          15
  23
  24 static inline unsigned long
  25 swap_ulong(volatile unsigned long *ptr, unsigned long val)
  26 {
  27         __asm__ __volatile__("swap [%1], %0\n\t" :
  28                              "=&r" (val), "=&r" (ptr) :
  29                              "0" (val), "1" (ptr));
  30         return val;
  31 }
  32
  33 static void smp4m_ipi_init(void);
  34 static void smp_setup_percpu_timer(void);
  35
  36 void __cpuinit smp4m_callin(void)
  37 {
  38         int cpuid = hard_smp_processor_id();
  39
  40         local_flush_cache_all();
  41         local_flush_tlb_all();
  42
  43         notify_cpu_starting(cpuid);
  44
  45         /* Get our local ticker going. */
  46         smp_setup_percpu_timer();
  47
  48         calibrate_delay();
  49         smp_store_cpu_info(cpuid);
  50
  51         local_flush_cache_all();
  52         local_flush_tlb_all();
  53
  54         /*
  55          * Unblock the master CPU _only_ when the scheduler state
  56          * of all secondary CPUs will be up-to-date, so after
  57          * the SMP initialization the master will be just allowed
  58          * to call the scheduler code.
  59          */
  60         /* Allow master to continue. */
  61         swap_ulong(&cpu_callin_map[cpuid], 1);
  62
  63         /* XXX: What's up with all the flushes? */
  64         local_flush_cache_all();
  65         local_flush_tlb_all();
  66
  67         /* Fix idle thread fields. */
  68         __asm__ __volatile__("ld [%0], %%g6\n\t"
  69                              : : "r" (&current_set[cpuid])
  70                              : "memory" /* paranoid */);
  71
  72         /* Attach to the address space of init_task. */
  73         atomic_inc(&init_mm.mm_count);
  74         current->active_mm = &init_mm;
  75
  76         while (!cpumask_test_cpu(cpuid, &smp_commenced_mask))
  77                 mb();
  78
  79         local_irq_enable();
  80
  81         set_cpu_online(cpuid, true);
  82 }
  83
  84 /*
  85  *      Cycle through the processors asking the PROM to start each one.
  86  */
  87 void __init smp4m_boot_cpus(void)
  88 {
  89         smp4m_ipi_init();
  90         smp_setup_percpu_timer();
  91         local_flush_cache_all();
  92 }
  93
  94 int __cpuinit smp4m_boot_one_cpu(int i, struct task_struct *idle)
  95 {
  96         unsigned long *entry = &sun4m_cpu_startup;
  97         int timeout;
  98         int cpu_node;
  99
 100         cpu_find_by_mid(i, &cpu_node);
 101         current_set[i] = task_thread_info(idle);
 102
 103         /* See trampoline.S for details... */
 104         entry += ((i - 1) * 3);
 105
 106         /*
 107          * Initialize the contexts table
 108          * Since the call to prom_startcpu() trashes the structure,
 109          * we need to re-initialize it for each cpu
 110          */
 111         smp_penguin_ctable.which_io = 0;
 112         smp_penguin_ctable.phys_addr = (unsigned int) srmmu_ctx_table_phys;
 113         smp_penguin_ctable.reg_size = 0;
 114
 115         /* whirrr, whirrr, whirrrrrrrrr... */
 116         printk(KERN_INFO "Starting CPU %d at %p\n", i, entry);
 117         local_flush_cache_all();
 118         prom_startcpu(cpu_node, &smp_penguin_ctable, 0, (char *)entry);
 119
 120         /* wheee... it's going... */
 121         for (timeout = 0; timeout < 10000; timeout++) {
 122                 if (cpu_callin_map[i])
 123                         break;
 124                 udelay(200);
 125         }
 126
 127         if (!(cpu_callin_map[i])) {
 128                 printk(KERN_ERR "Processor %d is stuck.\n", i);
 129                 return -ENODEV;
 130         }
 131
 132         local_flush_cache_all();
 133         return 0;
 134 }
 135
 136 void __init smp4m_smp_done(void)
 137 {
 138         int i, first;
 139         int *prev;
 140
 141         /* setup cpu list for irq rotation */
 142         first = 0;
 143         prev = &first;
 144         for_each_online_cpu(i) {
 145                 *prev = i;
 146                 prev = &cpu_data(i).next;
 147         }
 148         *prev = first;
 149         local_flush_cache_all();
 150
 151         /* Ok, they are spinning and ready to go. */
 152 }
 153
 154
 155 /* Initialize IPIs on the SUN4M SMP machine */
 156 static void __init smp4m_ipi_init(void)
 157 {
 158 }
 159
 160 static void smp4m_ipi_resched(int cpu)
 161 {
 162         set_cpu_int(cpu, IRQ_IPI_RESCHED);
 163 }
 164
 165 static void smp4m_ipi_single(int cpu)
 166 {
 167         set_cpu_int(cpu, IRQ_IPI_SINGLE);
 168 }
 169
 170 static void smp4m_ipi_mask_one(int cpu)
 171 {
 172         set_cpu_int(cpu, IRQ_IPI_MASK);
 173 }
 174
 175 static struct smp_funcall {
 176         smpfunc_t func;
 177         unsigned long arg1;
 178         unsigned long arg2;
 179         unsigned long arg3;
 180         unsigned long arg4;
 181         unsigned long arg5;
 182         unsigned long processors_in[SUN4M_NCPUS];  /* Set when ipi entered. */
 183         unsigned long processors_out[SUN4M_NCPUS]; /* Set when ipi exited. */
 184 } ccall_info;
 185
 186 static DEFINE_SPINLOCK(cross_call_lock);
 187
 188 /* Cross calls must be serialized, at least currently. */
 189 static void smp4m_cross_call(smpfunc_t func, cpumask_t mask, unsigned long arg1,
 190                              unsigned long arg2, unsigned long arg3,
 191                              unsigned long arg4)
 192 {
 193                 register int ncpus = SUN4M_NCPUS;
 194                 unsigned long flags;
 195
 196                 spin_lock_irqsave(&cross_call_lock, flags);
 197
 198                 /* Init function glue. */
 199                 ccall_info.func = func;
 200                 ccall_info.arg1 = arg1;
 201                 ccall_info.arg2 = arg2;
 202                 ccall_info.arg3 = arg3;
 203                 ccall_info.arg4 = arg4;
 204                 ccall_info.arg5 = 0;
 205
 206                 /* Init receive/complete mapping, plus fire the IPI's off. */
 207                 {
 208                         register int i;
 209
 210                         cpumask_clear_cpu(smp_processor_id(), &mask);
 211                         cpumask_and(&mask, cpu_online_mask, &mask);
 212                         for (i = 0; i < ncpus; i++) {
 213                                 if (cpumask_test_cpu(i, &mask)) {
 214                                         ccall_info.processors_in[i] = 0;
 215                                         ccall_info.processors_out[i] = 0;
 216                                         set_cpu_int(i, IRQ_CROSS_CALL);
 217                                 } else {
 218                                         ccall_info.processors_in[i] = 1;
 219                                         ccall_info.processors_out[i] = 1;
 220                                 }
 221                         }
 222                 }
 223
 224                 {
 225                         register int i;
 226
 227                         i = 0;
 228                         do {
 229                                 if (!cpumask_test_cpu(i, &mask))
 230                                         continue;
 231                                 while (!ccall_info.processors_in[i])
 232                                         barrier();
 233                         } while (++i < ncpus);
 234
 235                         i = 0;
 236                         do {
 237                                 if (!cpumask_test_cpu(i, &mask))
 238                                         continue;
 239                                 while (!ccall_info.processors_out[i])
 240                                         barrier();
 241                         } while (++i < ncpus);
 242                 }
 243                 spin_unlock_irqrestore(&cross_call_lock, flags);
 244 }
 245
 246 /* Running cross calls. */
 247 void smp4m_cross_call_irq(void)
 248 {
 249         int i = smp_processor_id();
 250
 251         ccall_info.processors_in[i] = 1;
 252         ccall_info.func(ccall_info.arg1, ccall_info.arg2, ccall_info.arg3,
 253                         ccall_info.arg4, ccall_info.arg5);
 254         ccall_info.processors_out[i] = 1;
 255 }
 256
 257 void smp4m_percpu_timer_interrupt(struct pt_regs *regs)
 258 {
 259         struct pt_regs *old_regs;
 260         int cpu = smp_processor_id();
 261
 262         old_regs = set_irq_regs(regs);
 263
 264         sun4m_clear_profile_irq(cpu);
 265
 266         profile_tick(CPU_PROFILING);
 267
 268         if (!--prof_counter(cpu)) {
 269                 int user = user_mode(regs);
 270
 271                 irq_enter();
 272                 update_process_times(user);
 273                 irq_exit();
 274
 275                 prof_counter(cpu) = prof_multiplier(cpu);
 276         }
 277         set_irq_regs(old_regs);
 278 }
 279
 280 static void __cpuinit smp_setup_percpu_timer(void)
 281 {
 282         int cpu = smp_processor_id();
 283
 284         prof_counter(cpu) = prof_multiplier(cpu) = 1;
 285         load_profile_irq(cpu, lvl14_resolution);
 286
 287         if (cpu == boot_cpu_id)
 288                 sun4m_unmask_profile_irq();
 289 }
 290
 291 static void __init smp4m_blackbox_id(unsigned *addr)
 292 {
 293         int rd = *addr & 0x3e000000;
 294         int rs1 = rd >> 11;
 295
 296         addr[0] = 0x81580000 | rd;              /* rd %tbr, reg */
 297         addr[1] = 0x8130200c | rd | rs1;        /* srl reg, 0xc, reg */
 298         addr[2] = 0x80082003 | rd | rs1;        /* and reg, 3, reg */
 299 }
 300
 301 static void __init smp4m_blackbox_current(unsigned *addr)
 302 {
 303         int rd = *addr & 0x3e000000;
 304         int rs1 = rd >> 11;
 305
 306         addr[0] = 0x81580000 | rd;              /* rd %tbr, reg */
 307         addr[2] = 0x8130200a | rd | rs1;        /* srl reg, 0xa, reg */
 308         addr[4] = 0x8008200c | rd | rs1;        /* and reg, 0xc, reg */
 309 }
 310
 311 void __init sun4m_init_smp(void)
 312 {
 313         BTFIXUPSET_BLACKBOX(hard_smp_processor_id, smp4m_blackbox_id);
 314         BTFIXUPSET_BLACKBOX(load_current, smp4m_blackbox_current);
 315         BTFIXUPSET_CALL(smp_cross_call, smp4m_cross_call, BTFIXUPCALL_NORM);
 316         BTFIXUPSET_CALL(__hard_smp_processor_id, __smp4m_processor_id, BTFIXUPCALL_NORM);
 317         BTFIXUPSET_CALL(smp_ipi_resched, smp4m_ipi_resched, BTFIXUPCALL_NORM);
 318         BTFIXUPSET_CALL(smp_ipi_single, smp4m_ipi_single, BTFIXUPCALL_NORM);
 319         BTFIXUPSET_CALL(smp_ipi_mask_one, smp4m_ipi_mask_one, BTFIXUPCALL_NORM);
 320 }