arch/sparc/kernel/leon_kernel.c

   1 /*
   2  * Copyright (C) 2009 Daniel Hellstrom (daniel@gaisler.com) Aeroflex Gaisler AB
   3  * Copyright (C) 2009 Konrad Eisele (konrad@gaisler.com) Aeroflex Gaisler AB
   4  */
   5
   6 #include <linux/kernel.h>
   7 #include <linux/errno.h>
   8 #include <linux/mutex.h>
   9 #include <linux/of.h>
  10 #include <linux/of_platform.h>
  11 #include <linux/interrupt.h>
  12 #include <linux/of_device.h>
  13 #include <linux/clocksource.h>
  14 #include <linux/clockchips.h>
  15
  16 #include <asm/oplib.h>
  17 #include <asm/timer.h>
  18 #include <asm/prom.h>
  19 #include <asm/leon.h>
  20 #include <asm/leon_amba.h>
  21 #include <asm/traps.h>
  22 #include <asm/cacheflush.h>
  23 #include <asm/smp.h>
  24 #include <asm/setup.h>
  25
  26 #include "kernel.h"
  27 #include "prom.h"
  28 #include "irq.h"
  29
  30 struct leon3_irqctrl_regs_map *leon3_irqctrl_regs; /* interrupt controller base address */
  31 struct leon3_gptimer_regs_map *leon3_gptimer_regs; /* timer controller base address */
  32
  33 int leondebug_irq_disable;
  34 int leon_debug_irqout;
  35 static int dummy_master_l10_counter;
  36 unsigned long amba_system_id;
  37 static DEFINE_SPINLOCK(leon_irq_lock);
  38
  39 unsigned long leon3_gptimer_irq; /* interrupt controller irq number */
  40 unsigned long leon3_gptimer_idx; /* Timer Index (0..6) within Timer Core */
  41 int leon3_ticker_irq; /* Timer ticker IRQ */
  42 unsigned int sparc_leon_eirq;
  43 #define LEON_IMASK(cpu) (&leon3_irqctrl_regs->mask[cpu])
  44 #define LEON_IACK (&leon3_irqctrl_regs->iclear)
  45 #define LEON_DO_ACK_HW 1
  46
  47 /* Return the last ACKed IRQ by the Extended IRQ controller. It has already
  48  * been (automatically) ACKed when the CPU takes the trap.
  49  */
  50 static inline unsigned int leon_eirq_get(int cpu)
  51 {
  52         return LEON3_BYPASS_LOAD_PA(&leon3_irqctrl_regs->intid[cpu]) & 0x1f;
  53 }
  54
  55 /* Handle one or multiple IRQs from the extended interrupt controller */
  56 static void leon_handle_ext_irq(unsigned int irq, struct irq_desc *desc)
  57 {
  58         unsigned int eirq;
  59         int cpu = sparc_leon3_cpuid();
  60
  61         eirq = leon_eirq_get(cpu);
  62         if ((eirq & 0x10) && irq_map[eirq]->irq) /* bit4 tells if IRQ happened */
  63                 generic_handle_irq(irq_map[eirq]->irq);
  64 }
  65
  66 /* The extended IRQ controller has been found, this function registers it */
  67 void leon_eirq_setup(unsigned int eirq)
  68 {
  69         unsigned long mask, oldmask;
  70         unsigned int veirq;
  71
  72         if (eirq < 1 || eirq > 0xf) {
  73                 printk(KERN_ERR "LEON EXT IRQ NUMBER BAD: %d\n", eirq);
  74                 return;
  75         }
  76
  77         veirq = leon_build_device_irq(eirq, leon_handle_ext_irq, "extirq", 0);
  78
  79         /*
  80          * Unmask the Extended IRQ, the IRQs routed through the Ext-IRQ
  81          * controller have a mask-bit of their own, so this is safe.
  82          */
  83         irq_link(veirq);
  84         mask = 1 << eirq;
  85         oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(boot_cpu_id));
  86         LEON3_BYPASS_STORE_PA(LEON_IMASK(boot_cpu_id), (oldmask | mask));
  87         sparc_leon_eirq = eirq;
  88 }
  89
  90 unsigned long leon_get_irqmask(unsigned int irq)
  91 {
  92         unsigned long mask;
  93
  94         if (!irq || ((irq > 0xf) && !sparc_leon_eirq)
  95             || ((irq > 0x1f) && sparc_leon_eirq)) {
  96                 printk(KERN_ERR
  97                        "leon_get_irqmask: false irq number: %d\n", irq);
  98                 mask = 0;
  99         } else {
 100                 mask = LEON_HARD_INT(irq);
 101         }
 102         return mask;
 103 }
 104
 105 #ifdef CONFIG_SMP
 106 static int irq_choose_cpu(const struct cpumask *affinity)
 107 {
 108         cpumask_t mask;
 109
 110         cpumask_and(&mask, cpu_online_mask, affinity);
 111         if (cpumask_equal(&mask, cpu_online_mask) || cpumask_empty(&mask))
 112                 return boot_cpu_id;
 113         else
 114                 return cpumask_first(&mask);
 115 }
 116 #else
 117 #define irq_choose_cpu(affinity) boot_cpu_id
 118 #endif
 119
 120 static int leon_set_affinity(struct irq_data *data, const struct cpumask *dest,
 121                              bool force)
 122 {
 123         unsigned long mask, oldmask, flags;
 124         int oldcpu, newcpu;
 125
 126         mask = (unsigned long)data->chip_data;
 127         oldcpu = irq_choose_cpu(data->affinity);
 128         newcpu = irq_choose_cpu(dest);
 129
 130         if (oldcpu == newcpu)
 131                 goto out;
 132
 133         /* unmask on old CPU first before enabling on the selected CPU */
 134         spin_lock_irqsave(&leon_irq_lock, flags);
 135         oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(oldcpu));
 136         LEON3_BYPASS_STORE_PA(LEON_IMASK(oldcpu), (oldmask & ~mask));
 137         oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(newcpu));
 138         LEON3_BYPASS_STORE_PA(LEON_IMASK(newcpu), (oldmask | mask));
 139         spin_unlock_irqrestore(&leon_irq_lock, flags);
 140 out:
 141         return IRQ_SET_MASK_OK;
 142 }
 143
 144 static void leon_unmask_irq(struct irq_data *data)
 145 {
 146         unsigned long mask, oldmask, flags;
 147         int cpu;
 148
 149         mask = (unsigned long)data->chip_data;
 150         cpu = irq_choose_cpu(data->affinity);
 151         spin_lock_irqsave(&leon_irq_lock, flags);
 152         oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(cpu));
 153         LEON3_BYPASS_STORE_PA(LEON_IMASK(cpu), (oldmask | mask));
 154         spin_unlock_irqrestore(&leon_irq_lock, flags);
 155 }
 156
 157 static void leon_mask_irq(struct irq_data *data)
 158 {
 159         unsigned long mask, oldmask, flags;
 160         int cpu;
 161
 162         mask = (unsigned long)data->chip_data;
 163         cpu = irq_choose_cpu(data->affinity);
 164         spin_lock_irqsave(&leon_irq_lock, flags);
 165         oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(cpu));
 166         LEON3_BYPASS_STORE_PA(LEON_IMASK(cpu), (oldmask & ~mask));
 167         spin_unlock_irqrestore(&leon_irq_lock, flags);
 168 }
 169
 170 static unsigned int leon_startup_irq(struct irq_data *data)
 171 {
 172         irq_link(data->irq);
 173         leon_unmask_irq(data);
 174         return 0;
 175 }
 176
 177 static void leon_shutdown_irq(struct irq_data *data)
 178 {
 179         leon_mask_irq(data);
 180         irq_unlink(data->irq);
 181 }
 182
 183 /* Used by external level sensitive IRQ handlers on the LEON: ACK IRQ ctrl */
 184 static void leon_eoi_irq(struct irq_data *data)
 185 {
 186         unsigned long mask = (unsigned long)data->chip_data;
 187
 188         if (mask & LEON_DO_ACK_HW)
 189                 LEON3_BYPASS_STORE_PA(LEON_IACK, mask & ~LEON_DO_ACK_HW);
 190 }
 191
 192 static struct irq_chip leon_irq = {
 193         .name                   = "leon",
 194         .irq_startup            = leon_startup_irq,
 195         .irq_shutdown           = leon_shutdown_irq,
 196         .irq_mask               = leon_mask_irq,
 197         .irq_unmask             = leon_unmask_irq,
 198         .irq_eoi                = leon_eoi_irq,
 199         .irq_set_affinity       = leon_set_affinity,
 200 };
 201
 202 /*
 203  * Build a LEON IRQ for the edge triggered LEON IRQ controller:
 204  *  Edge (normal) IRQ           - handle_simple_irq, ack=DONT-CARE, never ack
 205  *  Level IRQ (PCI|Level-GPIO)  - handle_fasteoi_irq, ack=1, ack after ISR
 206  *  Per-CPU Edge                - handle_percpu_irq, ack=0
 207  */
 208 unsigned int leon_build_device_irq(unsigned int real_irq,
 209                                     irq_flow_handler_t flow_handler,
 210                                     const char *name, int do_ack)
 211 {
 212         unsigned int irq;
 213         unsigned long mask;
 214
 215         irq = 0;
 216         mask = leon_get_irqmask(real_irq);
 217         if (mask == 0)
 218                 goto out;
 219
 220         irq = irq_alloc(real_irq, real_irq);
 221         if (irq == 0)
 222                 goto out;
 223
 224         if (do_ack)
 225                 mask |= LEON_DO_ACK_HW;
 226
 227         irq_set_chip_and_handler_name(irq, &leon_irq,
 228                                       flow_handler, name);
 229         irq_set_chip_data(irq, (void *)mask);
 230
 231 out:
 232         return irq;
 233 }
 234
 235 static unsigned int _leon_build_device_irq(struct platform_device *op,
 236                                            unsigned int real_irq)
 237 {
 238         return leon_build_device_irq(real_irq, handle_simple_irq, "edge", 0);
 239 }
 240
 241 void leon_update_virq_handling(unsigned int virq,
 242                               irq_flow_handler_t flow_handler,
 243                               const char *name, int do_ack)
 244 {
 245         unsigned long mask = (unsigned long)irq_get_chip_data(virq);
 246
 247         mask &= ~LEON_DO_ACK_HW;
 248         if (do_ack)
 249                 mask |= LEON_DO_ACK_HW;
 250
 251         irq_set_chip_and_handler_name(virq, &leon_irq,
 252                                       flow_handler, name);
 253         irq_set_chip_data(virq, (void *)mask);
 254 }
 255
 256 static u32 leon_cycles_offset(void)
 257 {
 258         u32 rld, val, off;
 259         rld = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].rld);
 260         val = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].val);
 261         off = rld - val;
 262         return rld - val;
 263 }
 264
 265 #ifdef CONFIG_SMP
 266
 267 /* smp clockevent irq */
 268 irqreturn_t leon_percpu_timer_ce_interrupt(int irq, void *unused)
 269 {
 270         struct clock_event_device *ce;
 271         int cpu = smp_processor_id();
 272
 273         leon_clear_profile_irq(cpu);
 274
 275         ce = &per_cpu(sparc32_clockevent, cpu);
 276
 277         irq_enter();
 278         if (ce->event_handler)
 279                 ce->event_handler(ce);
 280         irq_exit();
 281
 282         return IRQ_HANDLED;
 283 }
 284
 285 #endif /* CONFIG_SMP */
 286
 287 void __init leon_init_timers(void)
 288 {
 289         int irq, eirq;
 290         struct device_node *rootnp, *np, *nnp;
 291         struct property *pp;
 292         int len;
 293         int icsel;
 294         int ampopts;
 295         int err;
 296
 297         sparc_config.get_cycles_offset = leon_cycles_offset;
 298         sparc_config.cs_period = 1000000 / HZ;
 299         sparc_config.features |= FEAT_L10_CLOCKSOURCE;
 300
 301 #ifndef CONFIG_SMP
 302         sparc_config.features |= FEAT_L10_CLOCKEVENT;
 303 #endif
 304
 305         leondebug_irq_disable = 0;
 306         leon_debug_irqout = 0;
 307         master_l10_counter = (unsigned int *)&dummy_master_l10_counter;
 308         dummy_master_l10_counter = 0;
 309
 310         rootnp = of_find_node_by_path("/ambapp0");
 311         if (!rootnp)
 312                 goto bad;
 313
 314         /* Find System ID: GRLIB build ID and optional CHIP ID */
 315         pp = of_find_property(rootnp, "systemid", &len);
 316         if (pp)
 317                 amba_system_id = *(unsigned long *)pp->value;
 318
 319         /* Find IRQMP IRQ Controller Registers base adr otherwise bail out */
 320         np = of_find_node_by_name(rootnp, "GAISLER_IRQMP");
 321         if (!np) {
 322                 np = of_find_node_by_name(rootnp, "01_00d");
 323                 if (!np)
 324                         goto bad;
 325         }
 326         pp = of_find_property(np, "reg", &len);
 327         if (!pp)
 328                 goto bad;
 329         leon3_irqctrl_regs = *(struct leon3_irqctrl_regs_map **)pp->value;
 330
 331         /* Find GPTIMER Timer Registers base address otherwise bail out. */
 332         nnp = rootnp;
 333         do {
 334                 np = of_find_node_by_name(nnp, "GAISLER_GPTIMER");
 335                 if (!np) {
 336                         np = of_find_node_by_name(nnp, "01_011");
 337                         if (!np)
 338                                 goto bad;
 339                 }
 340
 341                 ampopts = 0;
 342                 pp = of_find_property(np, "ampopts", &len);
 343                 if (pp) {
 344                         ampopts = *(int *)pp->value;
 345                         if (ampopts == 0) {
 346                                 /* Skip this instance, resource already
 347                                  * allocated by other OS */
 348                                 nnp = np;
 349                                 continue;
 350                         }
 351                 }
 352
 353                 /* Select Timer-Instance on Timer Core. Default is zero */
 354                 leon3_gptimer_idx = ampopts & 0x7;
 355
 356                 pp = of_find_property(np, "reg", &len);
 357                 if (pp)
 358                         leon3_gptimer_regs = *(struct leon3_gptimer_regs_map **)
 359                                                 pp->value;
 360                 pp = of_find_property(np, "interrupts", &len);
 361                 if (pp)
 362                         leon3_gptimer_irq = *(unsigned int *)pp->value;
 363         } while (0);
 364
 365         if (!(leon3_gptimer_regs && leon3_irqctrl_regs && leon3_gptimer_irq))
 366                 goto bad;
 367
 368         LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].val, 0);
 369         LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].rld,
 370                                 (((1000000 / HZ) - 1)));
 371         LEON3_BYPASS_STORE_PA(
 372                         &leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl, 0);
 373
 374 #ifdef CONFIG_SMP
 375         leon3_ticker_irq = leon3_gptimer_irq + 1 + leon3_gptimer_idx;
 376
 377         if (!(LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->config) &
 378               (1<<LEON3_GPTIMER_SEPIRQ))) {
 379                 printk(KERN_ERR "timer not configured with separate irqs\n");
 380                 BUG();
 381         }
 382
 383         LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx+1].val,
 384                                 0);
 385         LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx+1].rld,
 386                                 (((1000000/HZ) - 1)));
 387         LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx+1].ctrl,
 388                                 0);
 389 #endif
 390
 391         /*
 392          * The IRQ controller may (if implemented) consist of multiple
 393          * IRQ controllers, each mapped on a 4Kb boundary.
 394          * Each CPU may be routed to different IRQCTRLs, however
 395          * we assume that all CPUs (in SMP system) is routed to the
 396          * same IRQ Controller, and for non-SMP only one IRQCTRL is
 397          * accessed anyway.
 398          * In AMP systems, Linux must run on CPU0 for the time being.
 399          */
 400         icsel = LEON3_BYPASS_LOAD_PA(&leon3_irqctrl_regs->icsel[boot_cpu_id/8]);
 401         icsel = (icsel >> ((7 - (boot_cpu_id&0x7)) * 4)) & 0xf;
 402         leon3_irqctrl_regs += icsel;
 403
 404         /* Mask all IRQs on boot-cpu IRQ controller */
 405         LEON3_BYPASS_STORE_PA(&leon3_irqctrl_regs->mask[boot_cpu_id], 0);
 406
 407         /* Probe extended IRQ controller */
 408         eirq = (LEON3_BYPASS_LOAD_PA(&leon3_irqctrl_regs->mpstatus)
 409                 >> 16) & 0xf;
 410         if (eirq != 0)
 411                 leon_eirq_setup(eirq);
 412
 413         irq = _leon_build_device_irq(NULL, leon3_gptimer_irq+leon3_gptimer_idx);
 414         err = request_irq(irq, timer_interrupt, IRQF_TIMER, "timer", NULL);
 415         if (err) {
 416                 printk(KERN_ERR "unable to attach timer IRQ%d\n", irq);
 417                 prom_halt();
 418         }
 419
 420 #ifdef CONFIG_SMP
 421         {
 422                 unsigned long flags;
 423
 424                 /*
 425                  * In SMP, sun4m adds a IPI handler to IRQ trap handler that
 426                  * LEON never must take, sun4d and LEON overwrites the branch
 427                  * with a NOP.
 428                  */
 429                 local_irq_save(flags);
 430                 patchme_maybe_smp_msg[0] = 0x01000000; /* NOP out the branch */
 431                 local_ops->cache_all();
 432                 local_irq_restore(flags);
 433         }
 434 #endif
 435
 436         LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl,
 437                               LEON3_GPTIMER_EN |
 438                               LEON3_GPTIMER_RL |
 439                               LEON3_GPTIMER_LD |
 440                               LEON3_GPTIMER_IRQEN);
 441
 442 #ifdef CONFIG_SMP
 443         /* Install per-cpu IRQ handler for broadcasted ticker */
 444         irq = leon_build_device_irq(leon3_ticker_irq, handle_percpu_irq,
 445                                     "per-cpu", 0);
 446         err = request_irq(irq, leon_percpu_timer_ce_interrupt,
 447                           IRQF_PERCPU | IRQF_TIMER, "ticker",
 448                           NULL);
 449         if (err) {
 450                 printk(KERN_ERR "unable to attach ticker IRQ%d\n", irq);
 451                 prom_halt();
 452         }
 453
 454         LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx+1].ctrl,
 455                               LEON3_GPTIMER_EN |
 456                               LEON3_GPTIMER_RL |
 457                               LEON3_GPTIMER_LD |
 458                               LEON3_GPTIMER_IRQEN);
 459 #endif
 460         return;
 461 bad:
 462         printk(KERN_ERR "No Timer/irqctrl found\n");
 463         BUG();
 464         return;
 465 }
 466
 467 static void leon_clear_clock_irq(void)
 468 {
 469 }
 470
 471 static void leon_load_profile_irq(int cpu, unsigned int limit)
 472 {
 473 }
 474
 475 void __init leon_trans_init(struct device_node *dp)
 476 {
 477         if (strcmp(dp->type, "cpu") == 0 && strcmp(dp->name, "<NULL>") == 0) {
 478                 struct property *p;
 479                 p = of_find_property(dp, "mid", (void *)0);
 480                 if (p) {
 481                         int mid;
 482                         dp->name = prom_early_alloc(5 + 1);
 483                         memcpy(&mid, p->value, p->length);
 484                         sprintf((char *)dp->name, "cpu%.2d", mid);
 485                 }
 486         }
 487 }
 488
 489 #ifdef CONFIG_SMP
 490 void leon_clear_profile_irq(int cpu)
 491 {
 492 }
 493
 494 void leon_enable_irq_cpu(unsigned int irq_nr, unsigned int cpu)
 495 {
 496         unsigned long mask, flags, *addr;
 497         mask = leon_get_irqmask(irq_nr);
 498         spin_lock_irqsave(&leon_irq_lock, flags);
 499         addr = (unsigned long *)LEON_IMASK(cpu);
 500         LEON3_BYPASS_STORE_PA(addr, (LEON3_BYPASS_LOAD_PA(addr) | mask));
 501         spin_unlock_irqrestore(&leon_irq_lock, flags);
 502 }
 503
 504 #endif
 505
 506 void __init leon_init_IRQ(void)
 507 {
 508         sparc_config.init_timers      = leon_init_timers;
 509         sparc_config.build_device_irq = _leon_build_device_irq;
 510         sparc_config.clock_rate       = 1000000;
 511         sparc_config.clear_clock_irq  = leon_clear_clock_irq;
 512         sparc_config.load_profile_irq = leon_load_profile_irq;
 513 }