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