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/clockchips.h>
   8 #include <linux/interrupt.h>
   9 #include <linux/profile.h>
  10 #include <linux/delay.h>
  11 #include <linux/cpu.h>
  12
  13 #include <asm/cacheflush.h>
  14 #include <asm/switch_to.h>
  15 #include <asm/tlbflush.h>
  16 #include <asm/timer.h>
  17
  18 #include "irq.h"
  19 #include "kernel.h"
  20
  21 #define IRQ_IPI_SINGLE          12
  22 #define IRQ_IPI_MASK            13
  23 #define IRQ_IPI_RESCHED         14
  24 #define IRQ_CROSS_CALL          15
  25
  26 static inline unsigned long
  27 swap_ulong(volatile unsigned long *ptr, unsigned long val)
  28 {
  29         __asm__ __volatile__("swap [%1], %0\n\t" :
  30                              "=&r" (val), "=&r" (ptr) :
  31                              "0" (val), "1" (ptr));
  32         return val;
  33 }
  34
  35 static void smp4m_ipi_init(void);
  36
  37 void __cpuinit smp4m_callin(void)
  38 {
  39         int cpuid = hard_smp_processor_id();
  40
  41         local_flush_cache_all();
  42         local_flush_tlb_all();
  43
  44         notify_cpu_starting(cpuid);
  45
  46         register_percpu_ce(cpuid);
  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         sun4m_unmask_profile_irq();
  91         local_flush_cache_all();
  92 }
  93
  94 int __cpuinit smp4m_boot_one_cpu(int i)
  95 {
  96         unsigned long *entry = &sun4m_cpu_startup;
  97         struct task_struct *p;
  98         int timeout;
  99         int cpu_node;
 100
 101         cpu_find_by_mid(i, &cpu_node);
 102
 103         /* Cook up an idler for this guy. */
 104         p = fork_idle(i);
 105         current_set[i] = task_thread_info(p);
 106         /* See trampoline.S for details... */
 107         entry += ((i - 1) * 3);
 108
 109         /*
 110          * Initialize the contexts table
 111          * Since the call to prom_startcpu() trashes the structure,
 112          * we need to re-initialize it for each cpu
 113          */
 114         smp_penguin_ctable.which_io = 0;
 115         smp_penguin_ctable.phys_addr = (unsigned int) srmmu_ctx_table_phys;
 116         smp_penguin_ctable.reg_size = 0;
 117
 118         /* whirrr, whirrr, whirrrrrrrrr... */
 119         printk(KERN_INFO "Starting CPU %d at %p\n", i, entry);
 120         local_flush_cache_all();
 121         prom_startcpu(cpu_node, &smp_penguin_ctable, 0, (char *)entry);
 122
 123         /* wheee... it's going... */
 124         for (timeout = 0; timeout < 10000; timeout++) {
 125                 if (cpu_callin_map[i])
 126                         break;
 127                 udelay(200);
 128         }
 129
 130         if (!(cpu_callin_map[i])) {
 131                 printk(KERN_ERR "Processor %d is stuck.\n", i);
 132                 return -ENODEV;
 133         }
 134
 135         local_flush_cache_all();
 136         return 0;
 137 }
 138
 139 void __init smp4m_smp_done(void)
 140 {
 141         int i, first;
 142         int *prev;
 143
 144         /* setup cpu list for irq rotation */
 145         first = 0;
 146         prev = &first;
 147         for_each_online_cpu(i) {
 148                 *prev = i;
 149                 prev = &cpu_data(i).next;
 150         }
 151         *prev = first;
 152         local_flush_cache_all();
 153
 154         /* Ok, they are spinning and ready to go. */
 155 }
 156
 157
 158 /* Initialize IPIs on the SUN4M SMP machine */
 159 static void __init smp4m_ipi_init(void)
 160 {
 161 }
 162
 163 static void smp4m_ipi_resched(int cpu)
 164 {
 165         set_cpu_int(cpu, IRQ_IPI_RESCHED);
 166 }
 167
 168 static void smp4m_ipi_single(int cpu)
 169 {
 170         set_cpu_int(cpu, IRQ_IPI_SINGLE);
 171 }
 172
 173 static void smp4m_ipi_mask_one(int cpu)
 174 {
 175         set_cpu_int(cpu, IRQ_IPI_MASK);
 176 }
 177
 178 static struct smp_funcall {
 179         smpfunc_t func;
 180         unsigned long arg1;
 181         unsigned long arg2;
 182         unsigned long arg3;
 183         unsigned long arg4;
 184         unsigned long arg5;
 185         unsigned long processors_in[SUN4M_NCPUS];  /* Set when ipi entered. */
 186         unsigned long processors_out[SUN4M_NCPUS]; /* Set when ipi exited. */
 187 } ccall_info;
 188
 189 static DEFINE_SPINLOCK(cross_call_lock);
 190
 191 /* Cross calls must be serialized, at least currently. */
 192 static void smp4m_cross_call(smpfunc_t func, cpumask_t mask, unsigned long arg1,
 193                              unsigned long arg2, unsigned long arg3,
 194                              unsigned long arg4)
 195 {
 196                 register int ncpus = SUN4M_NCPUS;
 197                 unsigned long flags;
 198
 199                 spin_lock_irqsave(&cross_call_lock, flags);
 200
 201                 /* Init function glue. */
 202                 ccall_info.func = func;
 203                 ccall_info.arg1 = arg1;
 204                 ccall_info.arg2 = arg2;
 205                 ccall_info.arg3 = arg3;
 206                 ccall_info.arg4 = arg4;
 207                 ccall_info.arg5 = 0;
 208
 209                 /* Init receive/complete mapping, plus fire the IPI's off. */
 210                 {
 211                         register int i;
 212
 213                         cpumask_clear_cpu(smp_processor_id(), &mask);
 214                         cpumask_and(&mask, cpu_online_mask, &mask);
 215                         for (i = 0; i < ncpus; i++) {
 216                                 if (cpumask_test_cpu(i, &mask)) {
 217                                         ccall_info.processors_in[i] = 0;
 218                                         ccall_info.processors_out[i] = 0;
 219                                         set_cpu_int(i, IRQ_CROSS_CALL);
 220                                 } else {
 221                                         ccall_info.processors_in[i] = 1;
 222                                         ccall_info.processors_out[i] = 1;
 223                                 }
 224                         }
 225                 }
 226
 227                 {
 228                         register int i;
 229
 230                         i = 0;
 231                         do {
 232                                 if (!cpumask_test_cpu(i, &mask))
 233                                         continue;
 234                                 while (!ccall_info.processors_in[i])
 235                                         barrier();
 236                         } while (++i < ncpus);
 237
 238                         i = 0;
 239                         do {
 240                                 if (!cpumask_test_cpu(i, &mask))
 241                                         continue;
 242                                 while (!ccall_info.processors_out[i])
 243                                         barrier();
 244                         } while (++i < ncpus);
 245                 }
 246                 spin_unlock_irqrestore(&cross_call_lock, flags);
 247 }
 248
 249 /* Running cross calls. */
 250 void smp4m_cross_call_irq(void)
 251 {
 252         int i = smp_processor_id();
 253
 254         ccall_info.processors_in[i] = 1;
 255         ccall_info.func(ccall_info.arg1, ccall_info.arg2, ccall_info.arg3,
 256                         ccall_info.arg4, ccall_info.arg5);
 257         ccall_info.processors_out[i] = 1;
 258 }
 259
 260 void smp4m_percpu_timer_interrupt(struct pt_regs *regs)
 261 {
 262         struct pt_regs *old_regs;
 263         struct clock_event_device *ce;
 264         int cpu = smp_processor_id();
 265
 266         old_regs = set_irq_regs(regs);
 267
 268         ce = &per_cpu(sparc32_clockevent, cpu);
 269
 270         if (ce->mode & CLOCK_EVT_MODE_PERIODIC)
 271                 sun4m_clear_profile_irq(cpu);
 272         else
 273                 load_profile_irq(cpu, 0); /* Is this needless? */
 274
 275         irq_enter();
 276         ce->event_handler(ce);
 277         irq_exit();
 278
 279         set_irq_regs(old_regs);
 280 }
 281
 282 static void __init smp4m_blackbox_id(unsigned *addr)
 283 {
 284         int rd = *addr & 0x3e000000;
 285         int rs1 = rd >> 11;
 286
 287         addr[0] = 0x81580000 | rd;              /* rd %tbr, reg */
 288         addr[1] = 0x8130200c | rd | rs1;        /* srl reg, 0xc, reg */
 289         addr[2] = 0x80082003 | rd | rs1;        /* and reg, 3, reg */
 290 }
 291
 292 static void __init smp4m_blackbox_current(unsigned *addr)
 293 {
 294         int rd = *addr & 0x3e000000;
 295         int rs1 = rd >> 11;
 296
 297         addr[0] = 0x81580000 | rd;              /* rd %tbr, reg */
 298         addr[2] = 0x8130200a | rd | rs1;        /* srl reg, 0xa, reg */
 299         addr[4] = 0x8008200c | rd | rs1;        /* and reg, 0xc, reg */
 300 }
 301
 302 void __init sun4m_init_smp(void)
 303 {
 304         BTFIXUPSET_BLACKBOX(hard_smp_processor_id, smp4m_blackbox_id);
 305         BTFIXUPSET_BLACKBOX(load_current, smp4m_blackbox_current);
 306         BTFIXUPSET_CALL(smp_cross_call, smp4m_cross_call, BTFIXUPCALL_NORM);
 307         BTFIXUPSET_CALL(__hard_smp_processor_id, __smp4m_processor_id, BTFIXUPCALL_NORM);
 308         BTFIXUPSET_CALL(smp_ipi_resched, smp4m_ipi_resched, BTFIXUPCALL_NORM);
 309         BTFIXUPSET_CALL(smp_ipi_single, smp4m_ipi_single, BTFIXUPCALL_NORM);
 310         BTFIXUPSET_CALL(smp_ipi_mask_one, smp4m_ipi_mask_one, BTFIXUPCALL_NORM);
 311 }