arch/sparc/kernel/leon_smp.c

   1 /* leon_smp.c: Sparc-Leon SMP support.
   2  *
   3  * based on sun4m_smp.c
   4  * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
   5  * Copyright (C) 2009 Daniel Hellstrom (daniel@gaisler.com) Aeroflex Gaisler AB
   6  * Copyright (C) 2009 Konrad Eisele (konrad@gaisler.com) Aeroflex Gaisler AB
   7  */
   8
   9 #include <asm/head.h>
  10
  11 #include <linux/kernel.h>
  12 #include <linux/sched.h>
  13 #include <linux/threads.h>
  14 #include <linux/smp.h>
  15 #include <linux/interrupt.h>
  16 #include <linux/kernel_stat.h>
  17 #include <linux/of.h>
  18 #include <linux/init.h>
  19 #include <linux/spinlock.h>
  20 #include <linux/mm.h>
  21 #include <linux/swap.h>
  22 #include <linux/profile.h>
  23 #include <linux/pm.h>
  24 #include <linux/delay.h>
  25 #include <linux/gfp.h>
  26 #include <linux/cpu.h>
  27 #include <linux/clockchips.h>
  28
  29 #include <asm/cacheflush.h>
  30 #include <asm/tlbflush.h>
  31
  32 #include <asm/ptrace.h>
  33 #include <linux/atomic.h>
  34 #include <asm/irq_regs.h>
  35 #include <asm/traps.h>
  36
  37 #include <asm/delay.h>
  38 #include <asm/irq.h>
  39 #include <asm/page.h>
  40 #include <asm/pgalloc.h>
  41 #include <asm/pgtable.h>
  42 #include <asm/oplib.h>
  43 #include <asm/cpudata.h>
  44 #include <asm/asi.h>
  45 #include <asm/leon.h>
  46 #include <asm/leon_amba.h>
  47 #include <asm/timer.h>
  48
  49 #include "kernel.h"
  50
  51 #ifdef CONFIG_SPARC_LEON
  52
  53 #include "irq.h"
  54
  55 extern ctxd_t *srmmu_ctx_table_phys;
  56 static int smp_processors_ready;
  57 extern volatile unsigned long cpu_callin_map[NR_CPUS];
  58 extern cpumask_t smp_commenced_mask;
  59 void __init leon_configure_cache_smp(void);
  60 static void leon_ipi_init(void);
  61
  62 /* IRQ number of LEON IPIs */
  63 int leon_ipi_irq = LEON3_IRQ_IPI_DEFAULT;
  64
  65 static inline unsigned long do_swap(volatile unsigned long *ptr,
  66                                     unsigned long val)
  67 {
  68         __asm__ __volatile__("swapa [%2] %3, %0\n\t" : "=&r"(val)
  69                              : "0"(val), "r"(ptr), "i"(ASI_LEON_DCACHE_MISS)
  70                              : "memory");
  71         return val;
  72 }
  73
  74 void __cpuinit leon_callin(void)
  75 {
  76         int cpuid = hard_smp_processor_id();
  77
  78         local_ops->cache_all();
  79         local_ops->tlb_all();
  80         leon_configure_cache_smp();
  81
  82         notify_cpu_starting(cpuid);
  83
  84         /* Get our local ticker going. */
  85         register_percpu_ce(cpuid);
  86
  87         calibrate_delay();
  88         smp_store_cpu_info(cpuid);
  89
  90         local_ops->cache_all();
  91         local_ops->tlb_all();
  92
  93         /*
  94          * Unblock the master CPU _only_ when the scheduler state
  95          * of all secondary CPUs will be up-to-date, so after
  96          * the SMP initialization the master will be just allowed
  97          * to call the scheduler code.
  98          * Allow master to continue.
  99          */
 100         do_swap(&cpu_callin_map[cpuid], 1);
 101
 102         local_ops->cache_all();
 103         local_ops->tlb_all();
 104
 105         /* Fix idle thread fields. */
 106         __asm__ __volatile__("ld [%0], %%g6\n\t" : : "r"(&current_set[cpuid])
 107                              : "memory" /* paranoid */);
 108
 109         /* Attach to the address space of init_task. */
 110         atomic_inc(&init_mm.mm_count);
 111         current->active_mm = &init_mm;
 112
 113         while (!cpumask_test_cpu(cpuid, &smp_commenced_mask))
 114                 mb();
 115
 116         local_irq_enable();
 117         set_cpu_online(cpuid, true);
 118 }
 119
 120 /*
 121  *      Cycle through the processors asking the PROM to start each one.
 122  */
 123
 124 extern struct linux_prom_registers smp_penguin_ctable;
 125
 126 void __init leon_configure_cache_smp(void)
 127 {
 128         unsigned long cfg = sparc_leon3_get_dcachecfg();
 129         int me = smp_processor_id();
 130
 131         if (ASI_LEON3_SYSCTRL_CFG_SSIZE(cfg) > 4) {
 132                 printk(KERN_INFO "Note: SMP with snooping only works on 4k cache, found %dk(0x%x) on cpu %d, disabling caches\n",
 133                      (unsigned int)ASI_LEON3_SYSCTRL_CFG_SSIZE(cfg),
 134                      (unsigned int)cfg, (unsigned int)me);
 135                 sparc_leon3_disable_cache();
 136         } else {
 137                 if (cfg & ASI_LEON3_SYSCTRL_CFG_SNOOPING) {
 138                         sparc_leon3_enable_snooping();
 139                 } else {
 140                         printk(KERN_INFO "Note: You have to enable snooping in the vhdl model cpu %d, disabling caches\n",
 141                              me);
 142                         sparc_leon3_disable_cache();
 143                 }
 144         }
 145
 146         local_ops->cache_all();
 147         local_ops->tlb_all();
 148 }
 149
 150 void leon_smp_setbroadcast(unsigned int mask)
 151 {
 152         int broadcast =
 153             ((LEON3_BYPASS_LOAD_PA(&(leon3_irqctrl_regs->mpstatus)) >>
 154               LEON3_IRQMPSTATUS_BROADCAST) & 1);
 155         if (!broadcast) {
 156                 prom_printf("######## !!!! The irqmp-ctrl must have broadcast enabled, smp wont work !!!!! ####### nr cpus: %d\n",
 157                      leon_smp_nrcpus());
 158                 if (leon_smp_nrcpus() > 1) {
 159                         BUG();
 160                 } else {
 161                         prom_printf("continue anyway\n");
 162                         return;
 163                 }
 164         }
 165         LEON_BYPASS_STORE_PA(&(leon3_irqctrl_regs->mpbroadcast), mask);
 166 }
 167
 168 unsigned int leon_smp_getbroadcast(void)
 169 {
 170         unsigned int mask;
 171         mask = LEON_BYPASS_LOAD_PA(&(leon3_irqctrl_regs->mpbroadcast));
 172         return mask;
 173 }
 174
 175 int leon_smp_nrcpus(void)
 176 {
 177         int nrcpu =
 178             ((LEON3_BYPASS_LOAD_PA(&(leon3_irqctrl_regs->mpstatus)) >>
 179               LEON3_IRQMPSTATUS_CPUNR) & 0xf) + 1;
 180         return nrcpu;
 181 }
 182
 183 void __init leon_boot_cpus(void)
 184 {
 185         int nrcpu = leon_smp_nrcpus();
 186         int me = smp_processor_id();
 187
 188         /* Setup IPI */
 189         leon_ipi_init();
 190
 191         printk(KERN_INFO "%d:(%d:%d) cpus mpirq at 0x%x\n", (unsigned int)me,
 192                (unsigned int)nrcpu, (unsigned int)NR_CPUS,
 193                (unsigned int)&(leon3_irqctrl_regs->mpstatus));
 194
 195         leon_enable_irq_cpu(LEON3_IRQ_CROSS_CALL, me);
 196         leon_enable_irq_cpu(LEON3_IRQ_TICKER, me);
 197         leon_enable_irq_cpu(leon_ipi_irq, me);
 198
 199         leon_smp_setbroadcast(1 << LEON3_IRQ_TICKER);
 200
 201         leon_configure_cache_smp();
 202         local_ops->cache_all();
 203
 204 }
 205
 206 int __cpuinit leon_boot_one_cpu(int i, struct task_struct *idle)
 207 {
 208         int timeout;
 209
 210         current_set[i] = task_thread_info(idle);
 211
 212         /* See trampoline.S:leon_smp_cpu_startup for details...
 213          * Initialize the contexts table
 214          * Since the call to prom_startcpu() trashes the structure,
 215          * we need to re-initialize it for each cpu
 216          */
 217         smp_penguin_ctable.which_io = 0;
 218         smp_penguin_ctable.phys_addr = (unsigned int)srmmu_ctx_table_phys;
 219         smp_penguin_ctable.reg_size = 0;
 220
 221         /* whirrr, whirrr, whirrrrrrrrr... */
 222         printk(KERN_INFO "Starting CPU %d : (irqmp: 0x%x)\n", (unsigned int)i,
 223                (unsigned int)&leon3_irqctrl_regs->mpstatus);
 224         local_ops->cache_all();
 225
 226         /* Make sure all IRQs are of from the start for this new CPU */
 227         LEON_BYPASS_STORE_PA(&leon3_irqctrl_regs->mask[i], 0);
 228
 229         /* Wake one CPU */
 230         LEON_BYPASS_STORE_PA(&(leon3_irqctrl_regs->mpstatus), 1 << i);
 231
 232         /* wheee... it's going... */
 233         for (timeout = 0; timeout < 10000; timeout++) {
 234                 if (cpu_callin_map[i])
 235                         break;
 236                 udelay(200);
 237         }
 238         printk(KERN_INFO "Started CPU %d\n", (unsigned int)i);
 239
 240         if (!(cpu_callin_map[i])) {
 241                 printk(KERN_ERR "Processor %d is stuck.\n", i);
 242                 return -ENODEV;
 243         } else {
 244                 leon_enable_irq_cpu(LEON3_IRQ_CROSS_CALL, i);
 245                 leon_enable_irq_cpu(LEON3_IRQ_TICKER, i);
 246                 leon_enable_irq_cpu(leon_ipi_irq, i);
 247         }
 248
 249         local_ops->cache_all();
 250         return 0;
 251 }
 252
 253 void __init leon_smp_done(void)
 254 {
 255
 256         int i, first;
 257         int *prev;
 258
 259         /* setup cpu list for irq rotation */
 260         first = 0;
 261         prev = &first;
 262         for (i = 0; i < NR_CPUS; i++) {
 263                 if (cpu_online(i)) {
 264                         *prev = i;
 265                         prev = &cpu_data(i).next;
 266                 }
 267         }
 268         *prev = first;
 269         local_ops->cache_all();
 270
 271         /* Free unneeded trap tables */
 272         if (!cpu_present(1)) {
 273                 ClearPageReserved(virt_to_page(&trapbase_cpu1));
 274                 init_page_count(virt_to_page(&trapbase_cpu1));
 275                 free_page((unsigned long)&trapbase_cpu1);
 276                 totalram_pages++;
 277                 num_physpages++;
 278         }
 279         if (!cpu_present(2)) {
 280                 ClearPageReserved(virt_to_page(&trapbase_cpu2));
 281                 init_page_count(virt_to_page(&trapbase_cpu2));
 282                 free_page((unsigned long)&trapbase_cpu2);
 283                 totalram_pages++;
 284                 num_physpages++;
 285         }
 286         if (!cpu_present(3)) {
 287                 ClearPageReserved(virt_to_page(&trapbase_cpu3));
 288                 init_page_count(virt_to_page(&trapbase_cpu3));
 289                 free_page((unsigned long)&trapbase_cpu3);
 290                 totalram_pages++;
 291                 num_physpages++;
 292         }
 293         /* Ok, they are spinning and ready to go. */
 294         smp_processors_ready = 1;
 295
 296 }
 297
 298 void leon_irq_rotate(int cpu)
 299 {
 300 }
 301
 302 struct leon_ipi_work {
 303         int single;
 304         int msk;
 305         int resched;
 306 };
 307
 308 static DEFINE_PER_CPU_SHARED_ALIGNED(struct leon_ipi_work, leon_ipi_work);
 309
 310 /* Initialize IPIs on the LEON, in order to save IRQ resources only one IRQ
 311  * is used for all three types of IPIs.
 312  */
 313 static void __init leon_ipi_init(void)
 314 {
 315         int cpu, len;
 316         struct leon_ipi_work *work;
 317         struct property *pp;
 318         struct device_node *rootnp;
 319         struct tt_entry *trap_table;
 320         unsigned long flags;
 321
 322         /* Find IPI IRQ or stick with default value */
 323         rootnp = of_find_node_by_path("/ambapp0");
 324         if (rootnp) {
 325                 pp = of_find_property(rootnp, "ipi_num", &len);
 326                 if (pp && (*(int *)pp->value))
 327                         leon_ipi_irq = *(int *)pp->value;
 328         }
 329         printk(KERN_INFO "leon: SMP IPIs at IRQ %d\n", leon_ipi_irq);
 330
 331         /* Adjust so that we jump directly to smpleon_ipi */
 332         local_irq_save(flags);
 333         trap_table = &sparc_ttable[SP_TRAP_IRQ1 + (leon_ipi_irq - 1)];
 334         trap_table->inst_three += smpleon_ipi - real_irq_entry;
 335         local_ops->cache_all();
 336         local_irq_restore(flags);
 337
 338         for_each_possible_cpu(cpu) {
 339                 work = &per_cpu(leon_ipi_work, cpu);
 340                 work->single = work->msk = work->resched = 0;
 341         }
 342 }
 343
 344 static void leon_send_ipi(int cpu, int level)
 345 {
 346         unsigned long mask;
 347         mask = leon_get_irqmask(level);
 348         LEON3_BYPASS_STORE_PA(&leon3_irqctrl_regs->force[cpu], mask);
 349 }
 350
 351 static void leon_ipi_single(int cpu)
 352 {
 353         struct leon_ipi_work *work = &per_cpu(leon_ipi_work, cpu);
 354
 355         /* Mark work */
 356         work->single = 1;
 357
 358         /* Generate IRQ on the CPU */
 359         leon_send_ipi(cpu, leon_ipi_irq);
 360 }
 361
 362 static void leon_ipi_mask_one(int cpu)
 363 {
 364         struct leon_ipi_work *work = &per_cpu(leon_ipi_work, cpu);
 365
 366         /* Mark work */
 367         work->msk = 1;
 368
 369         /* Generate IRQ on the CPU */
 370         leon_send_ipi(cpu, leon_ipi_irq);
 371 }
 372
 373 static void leon_ipi_resched(int cpu)
 374 {
 375         struct leon_ipi_work *work = &per_cpu(leon_ipi_work, cpu);
 376
 377         /* Mark work */
 378         work->resched = 1;
 379
 380         /* Generate IRQ on the CPU (any IRQ will cause resched) */
 381         leon_send_ipi(cpu, leon_ipi_irq);
 382 }
 383
 384 void leonsmp_ipi_interrupt(void)
 385 {
 386         struct leon_ipi_work *work = &__get_cpu_var(leon_ipi_work);
 387
 388         if (work->single) {
 389                 work->single = 0;
 390                 smp_call_function_single_interrupt();
 391         }
 392         if (work->msk) {
 393                 work->msk = 0;
 394                 smp_call_function_interrupt();
 395         }
 396         if (work->resched) {
 397                 work->resched = 0;
 398                 smp_resched_interrupt();
 399         }
 400 }
 401
 402 static struct smp_funcall {
 403         smpfunc_t func;
 404         unsigned long arg1;
 405         unsigned long arg2;
 406         unsigned long arg3;
 407         unsigned long arg4;
 408         unsigned long arg5;
 409         unsigned long processors_in[NR_CPUS];   /* Set when ipi entered. */
 410         unsigned long processors_out[NR_CPUS];  /* Set when ipi exited. */
 411 } ccall_info;
 412
 413 static DEFINE_SPINLOCK(cross_call_lock);
 414
 415 /* Cross calls must be serialized, at least currently. */
 416 static void leon_cross_call(smpfunc_t func, cpumask_t mask, unsigned long arg1,
 417                             unsigned long arg2, unsigned long arg3,
 418                             unsigned long arg4)
 419 {
 420         if (smp_processors_ready) {
 421                 register int high = NR_CPUS - 1;
 422                 unsigned long flags;
 423
 424                 spin_lock_irqsave(&cross_call_lock, flags);
 425
 426                 {
 427                         /* If you make changes here, make sure gcc generates proper code... */
 428                         register smpfunc_t f asm("i0") = func;
 429                         register unsigned long a1 asm("i1") = arg1;
 430                         register unsigned long a2 asm("i2") = arg2;
 431                         register unsigned long a3 asm("i3") = arg3;
 432                         register unsigned long a4 asm("i4") = arg4;
 433                         register unsigned long a5 asm("i5") = 0;
 434
 435                         __asm__ __volatile__("std %0, [%6]\n\t"
 436                                              "std %2, [%6 + 8]\n\t"
 437                                              "std %4, [%6 + 16]\n\t" : :
 438                                              "r"(f), "r"(a1), "r"(a2), "r"(a3),
 439                                              "r"(a4), "r"(a5),
 440                                              "r"(&ccall_info.func));
 441                 }
 442
 443                 /* Init receive/complete mapping, plus fire the IPI's off. */
 444                 {
 445                         register int i;
 446
 447                         cpumask_clear_cpu(smp_processor_id(), &mask);
 448                         cpumask_and(&mask, cpu_online_mask, &mask);
 449                         for (i = 0; i <= high; i++) {
 450                                 if (cpumask_test_cpu(i, &mask)) {
 451                                         ccall_info.processors_in[i] = 0;
 452                                         ccall_info.processors_out[i] = 0;
 453                                         leon_send_ipi(i, LEON3_IRQ_CROSS_CALL);
 454
 455                                 }
 456                         }
 457                 }
 458
 459                 {
 460                         register int i;
 461
 462                         i = 0;
 463                         do {
 464                                 if (!cpumask_test_cpu(i, &mask))
 465                                         continue;
 466
 467                                 while (!ccall_info.processors_in[i])
 468                                         barrier();
 469                         } while (++i <= high);
 470
 471                         i = 0;
 472                         do {
 473                                 if (!cpumask_test_cpu(i, &mask))
 474                                         continue;
 475
 476                                 while (!ccall_info.processors_out[i])
 477                                         barrier();
 478                         } while (++i <= high);
 479                 }
 480
 481                 spin_unlock_irqrestore(&cross_call_lock, flags);
 482         }
 483 }
 484
 485 /* Running cross calls. */
 486 void leon_cross_call_irq(void)
 487 {
 488         int i = smp_processor_id();
 489
 490         ccall_info.processors_in[i] = 1;
 491         ccall_info.func(ccall_info.arg1, ccall_info.arg2, ccall_info.arg3,
 492                         ccall_info.arg4, ccall_info.arg5);
 493         ccall_info.processors_out[i] = 1;
 494 }
 495
 496 static const struct sparc32_ipi_ops leon_ipi_ops = {
 497         .cross_call = leon_cross_call,
 498         .resched    = leon_ipi_resched,
 499         .single     = leon_ipi_single,
 500         .mask_one   = leon_ipi_mask_one,
 501 };
 502
 503 void __init leon_init_smp(void)
 504 {
 505         /* Patch ipi15 trap table */
 506         t_nmi[1] = t_nmi[1] + (linux_trap_ipi15_leon - linux_trap_ipi15_sun4m);
 507
 508         sparc32_ipi_ops = &leon_ipi_ops;
 509 }
 510
 511 #endif /* CONFIG_SPARC_LEON */