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/tlbflush.h>
  14
  15 #include "irq.h"
  16 #include "kernel.h"
  17
  18 #define IRQ_IPI_SINGLE          12
  19 #define IRQ_IPI_MASK            13
  20 #define IRQ_IPI_RESCHED         14
  21 #define IRQ_CROSS_CALL          15
  22
  23 static inline unsigned long
  24 swap_ulong(volatile unsigned long *ptr, unsigned long val)
  25 {
  26         __asm__ __volatile__("swap [%1], %0\n\t" :
  27                              "=&r" (val), "=&r" (ptr) :
  28                              "0" (val), "1" (ptr));
  29         return val;
  30 }
  31
  32 static void smp4m_ipi_init(void);
  33 static void smp_setup_percpu_timer(void);
  34
  35 void __cpuinit smp4m_callin(void)
  36 {
  37         int cpuid = hard_smp_processor_id();
  38
  39         local_flush_cache_all();
  40         local_flush_tlb_all();
  41
  42         notify_cpu_starting(cpuid);
  43
  44         /* Get our local ticker going. */
  45         smp_setup_percpu_timer();
  46
  47         calibrate_delay();
  48         smp_store_cpu_info(cpuid);
  49
  50         local_flush_cache_all();
  51         local_flush_tlb_all();
  52
  53         /*
  54          * Unblock the master CPU _only_ when the scheduler state
  55          * of all secondary CPUs will be up-to-date, so after
  56          * the SMP initialization the master will be just allowed
  57          * to call the scheduler code.
  58          */
  59         /* Allow master to continue. */
  60         swap_ulong(&cpu_callin_map[cpuid], 1);
  61
  62         /* XXX: What's up with all the flushes? */
  63         local_flush_cache_all();
  64         local_flush_tlb_all();
  65
  66         /* Fix idle thread fields. */
  67         __asm__ __volatile__("ld [%0], %%g6\n\t"
  68                              : : "r" (&current_set[cpuid])
  69                              : "memory" /* paranoid */);
  70
  71         /* Attach to the address space of init_task. */
  72         atomic_inc(&init_mm.mm_count);
  73         current->active_mm = &init_mm;
  74
  75         while (!cpumask_test_cpu(cpuid, &smp_commenced_mask))
  76                 mb();
  77
  78         local_irq_enable();
  79
  80         set_cpu_online(cpuid, true);
  81 }
  82
  83 /*
  84  *      Cycle through the processors asking the PROM to start each one.
  85  */
  86 void __init smp4m_boot_cpus(void)
  87 {
  88         smp4m_ipi_init();
  89         smp_setup_percpu_timer();
  90         local_flush_cache_all();
  91 }
  92
  93 int __cpuinit smp4m_boot_one_cpu(int i)
  94 {
  95         unsigned long *entry = &sun4m_cpu_startup;
  96         struct task_struct *p;
  97         int timeout;
  98         int cpu_node;
  99
 100         cpu_find_by_mid(i, &cpu_node);
 101
 102         /* Cook up an idler for this guy. */
 103         p = fork_idle(i);
 104         current_set[i] = task_thread_info(p);
 105         /* See trampoline.S for details... */
 106         entry += ((i - 1) * 3);
 107
 108         /*
 109          * Initialize the contexts table
 110          * Since the call to prom_startcpu() trashes the structure,
 111          * we need to re-initialize it for each cpu
 112          */
 113         smp_penguin_ctable.which_io = 0;
 114         smp_penguin_ctable.phys_addr = (unsigned int) srmmu_ctx_table_phys;
 115         smp_penguin_ctable.reg_size = 0;
 116
 117         /* whirrr, whirrr, whirrrrrrrrr... */
 118         printk(KERN_INFO "Starting CPU %d at %p\n", i, entry);
 119         local_flush_cache_all();
 120         prom_startcpu(cpu_node, &smp_penguin_ctable, 0, (char *)entry);
 121
 122         /* wheee... it's going... */
 123         for (timeout = 0; timeout < 10000; timeout++) {
 124                 if (cpu_callin_map[i])
 125                         break;
 126                 udelay(200);
 127         }
 128
 129         if (!(cpu_callin_map[i])) {
 130                 printk(KERN_ERR "Processor %d is stuck.\n", i);
 131                 return -ENODEV;
 132         }
 133
 134         local_flush_cache_all();
 135         return 0;
 136 }
 137
 138 void __init smp4m_smp_done(void)
 139 {
 140         int i, first;
 141         int *prev;
 142
 143         /* setup cpu list for irq rotation */
 144         first = 0;
 145         prev = &first;
 146         for_each_online_cpu(i) {
 147                 *prev = i;
 148                 prev = &cpu_data(i).next;
 149         }
 150         *prev = first;
 151         local_flush_cache_all();
 152
 153         /* Ok, they are spinning and ready to go. */
 154 }
 155
 156
 157 /* Initialize IPIs on the SUN4M SMP machine */
 158 static void __init smp4m_ipi_init(void)
 159 {
 160 }
 161
 162 static void smp4m_ipi_resched(int cpu)
 163 {
 164         set_cpu_int(cpu, IRQ_IPI_RESCHED);
 165 }
 166
 167 static void smp4m_ipi_single(int cpu)
 168 {
 169         set_cpu_int(cpu, IRQ_IPI_SINGLE);
 170 }
 171
 172 static void smp4m_ipi_mask_one(int cpu)
 173 {
 174         set_cpu_int(cpu, IRQ_IPI_MASK);
 175 }
 176
 177 static struct smp_funcall {
 178         smpfunc_t func;
 179         unsigned long arg1;
 180         unsigned long arg2;
 181         unsigned long arg3;
 182         unsigned long arg4;
 183         unsigned long arg5;
 184         unsigned long processors_in[SUN4M_NCPUS];  /* Set when ipi entered. */
 185         unsigned long processors_out[SUN4M_NCPUS]; /* Set when ipi exited. */
 186 } ccall_info;
 187
 188 static DEFINE_SPINLOCK(cross_call_lock);
 189
 190 /* Cross calls must be serialized, at least currently. */
 191 static void smp4m_cross_call(smpfunc_t func, cpumask_t mask, unsigned long arg1,
 192                              unsigned long arg2, unsigned long arg3,
 193                              unsigned long arg4)
 194 {
 195                 register int ncpus = SUN4M_NCPUS;
 196                 unsigned long flags;
 197
 198                 spin_lock_irqsave(&cross_call_lock, flags);
 199
 200                 /* Init function glue. */
 201                 ccall_info.func = func;
 202                 ccall_info.arg1 = arg1;
 203                 ccall_info.arg2 = arg2;
 204                 ccall_info.arg3 = arg3;
 205                 ccall_info.arg4 = arg4;
 206                 ccall_info.arg5 = 0;
 207
 208                 /* Init receive/complete mapping, plus fire the IPI's off. */
 209                 {
 210                         register int i;
 211
 212                         cpumask_clear_cpu(smp_processor_id(), &mask);
 213                         cpumask_and(&mask, cpu_online_mask, &mask);
 214                         for (i = 0; i < ncpus; i++) {
 215                                 if (cpumask_test_cpu(i, &mask)) {
 216                                         ccall_info.processors_in[i] = 0;
 217                                         ccall_info.processors_out[i] = 0;
 218                                         set_cpu_int(i, IRQ_CROSS_CALL);
 219                                 } else {
 220                                         ccall_info.processors_in[i] = 1;
 221                                         ccall_info.processors_out[i] = 1;
 222                                 }
 223                         }
 224                 }
 225
 226                 {
 227                         register int i;
 228
 229                         i = 0;
 230                         do {
 231                                 if (!cpumask_test_cpu(i, &mask))
 232                                         continue;
 233                                 while (!ccall_info.processors_in[i])
 234                                         barrier();
 235                         } while (++i < ncpus);
 236
 237                         i = 0;
 238                         do {
 239                                 if (!cpumask_test_cpu(i, &mask))
 240                                         continue;
 241                                 while (!ccall_info.processors_out[i])
 242                                         barrier();
 243                         } while (++i < ncpus);
 244                 }
 245                 spin_unlock_irqrestore(&cross_call_lock, flags);
 246 }
 247
 248 /* Running cross calls. */
 249 void smp4m_cross_call_irq(void)
 250 {
 251         int i = smp_processor_id();
 252
 253         ccall_info.processors_in[i] = 1;
 254         ccall_info.func(ccall_info.arg1, ccall_info.arg2, ccall_info.arg3,
 255                         ccall_info.arg4, ccall_info.arg5);
 256         ccall_info.processors_out[i] = 1;
 257 }
 258
 259 void smp4m_percpu_timer_interrupt(struct pt_regs *regs)
 260 {
 261         struct pt_regs *old_regs;
 262         int cpu = smp_processor_id();
 263
 264         old_regs = set_irq_regs(regs);
 265
 266         sun4m_clear_profile_irq(cpu);
 267
 268         profile_tick(CPU_PROFILING);
 269
 270         if (!--prof_counter(cpu)) {
 271                 int user = user_mode(regs);
 272
 273                 irq_enter();
 274                 update_process_times(user);
 275                 irq_exit();
 276
 277                 prof_counter(cpu) = prof_multiplier(cpu);
 278         }
 279         set_irq_regs(old_regs);
 280 }
 281
 282 static void __cpuinit smp_setup_percpu_timer(void)
 283 {
 284         int cpu = smp_processor_id();
 285
 286         prof_counter(cpu) = prof_multiplier(cpu) = 1;
 287         load_profile_irq(cpu, lvl14_resolution);
 288
 289         if (cpu == boot_cpu_id)
 290                 sun4m_unmask_profile_irq();
 291 }
 292
 293 static void __init smp4m_blackbox_id(unsigned *addr)
 294 {
 295         int rd = *addr & 0x3e000000;
 296         int rs1 = rd >> 11;
 297
 298         addr[0] = 0x81580000 | rd;              /* rd %tbr, reg */
 299         addr[1] = 0x8130200c | rd | rs1;        /* srl reg, 0xc, reg */
 300         addr[2] = 0x80082003 | rd | rs1;        /* and reg, 3, reg */
 301 }
 302
 303 static void __init smp4m_blackbox_current(unsigned *addr)
 304 {
 305         int rd = *addr & 0x3e000000;
 306         int rs1 = rd >> 11;
 307
 308         addr[0] = 0x81580000 | rd;              /* rd %tbr, reg */
 309         addr[2] = 0x8130200a | rd | rs1;        /* srl reg, 0xa, reg */
 310         addr[4] = 0x8008200c | rd | rs1;        /* and reg, 0xc, reg */
 311 }
 312
 313 void __init sun4m_init_smp(void)
 314 {
 315         BTFIXUPSET_BLACKBOX(hard_smp_processor_id, smp4m_blackbox_id);
 316         BTFIXUPSET_BLACKBOX(load_current, smp4m_blackbox_current);
 317         BTFIXUPSET_CALL(smp_cross_call, smp4m_cross_call, BTFIXUPCALL_NORM);
 318         BTFIXUPSET_CALL(__hard_smp_processor_id, __smp4m_processor_id, BTFIXUPCALL_NORM);
 319         BTFIXUPSET_CALL(smp_ipi_resched, smp4m_ipi_resched, BTFIXUPCALL_NORM);
 320         BTFIXUPSET_CALL(smp_ipi_single, smp4m_ipi_single, BTFIXUPCALL_NORM);
 321         BTFIXUPSET_CALL(smp_ipi_mask_one, smp4m_ipi_mask_one, BTFIXUPCALL_NORM);
 322 }