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         struct irq_bucket *p;
  60         int cpu = sparc_leon3_cpuid();
  61
  62         eirq = leon_eirq_get(cpu);
  63         p = irq_map[eirq];
  64         if ((eirq & 0x10) && p && p->irq) /* bit4 tells if IRQ happened */
  65                 generic_handle_irq(p->irq);
  66 }
  67
  68 /* The extended IRQ controller has been found, this function registers it */
  69 void leon_eirq_setup(unsigned int eirq)
  70 {
  71         unsigned long mask, oldmask;
  72         unsigned int veirq;
  73
  74         if (eirq < 1 || eirq > 0xf) {
  75                 printk(KERN_ERR "LEON EXT IRQ NUMBER BAD: %d\n", eirq);
  76                 return;
  77         }
  78
  79         veirq = leon_build_device_irq(eirq, leon_handle_ext_irq, "extirq", 0);
  80
  81         /*
  82          * Unmask the Extended IRQ, the IRQs routed through the Ext-IRQ
  83          * controller have a mask-bit of their own, so this is safe.
  84          */
  85         irq_link(veirq);
  86         mask = 1 << eirq;
  87         oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(boot_cpu_id));
  88         LEON3_BYPASS_STORE_PA(LEON_IMASK(boot_cpu_id), (oldmask | mask));
  89         sparc_leon_eirq = eirq;
  90 }
  91
  92 unsigned long leon_get_irqmask(unsigned int irq)
  93 {
  94         unsigned long mask;
  95
  96         if (!irq || ((irq > 0xf) && !sparc_leon_eirq)
  97             || ((irq > 0x1f) && sparc_leon_eirq)) {
  98                 printk(KERN_ERR
  99                        "leon_get_irqmask: false irq number: %d\n", irq);
 100                 mask = 0;
 101         } else {
 102                 mask = LEON_HARD_INT(irq);
 103         }
 104         return mask;
 105 }
 106
 107 #ifdef CONFIG_SMP
 108 static int irq_choose_cpu(const struct cpumask *affinity)
 109 {
 110         cpumask_t mask;
 111
 112         cpumask_and(&mask, cpu_online_mask, affinity);
 113         if (cpumask_equal(&mask, cpu_online_mask) || cpumask_empty(&mask))
 114                 return boot_cpu_id;
 115         else
 116                 return cpumask_first(&mask);
 117 }
 118 #else
 119 #define irq_choose_cpu(affinity) boot_cpu_id
 120 #endif
 121
 122 static int leon_set_affinity(struct irq_data *data, const struct cpumask *dest,
 123                              bool force)
 124 {
 125         unsigned long mask, oldmask, flags;
 126         int oldcpu, newcpu;
 127
 128         mask = (unsigned long)data->chip_data;
 129         oldcpu = irq_choose_cpu(data->affinity);
 130         newcpu = irq_choose_cpu(dest);
 131
 132         if (oldcpu == newcpu)
 133                 goto out;
 134
 135         /* unmask on old CPU first before enabling on the selected CPU */
 136         spin_lock_irqsave(&leon_irq_lock, flags);
 137         oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(oldcpu));
 138         LEON3_BYPASS_STORE_PA(LEON_IMASK(oldcpu), (oldmask & ~mask));
 139         oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(newcpu));
 140         LEON3_BYPASS_STORE_PA(LEON_IMASK(newcpu), (oldmask | mask));
 141         spin_unlock_irqrestore(&leon_irq_lock, flags);
 142 out:
 143         return IRQ_SET_MASK_OK;
 144 }
 145
 146 static void leon_unmask_irq(struct irq_data *data)
 147 {
 148         unsigned long mask, oldmask, flags;
 149         int cpu;
 150
 151         mask = (unsigned long)data->chip_data;
 152         cpu = irq_choose_cpu(data->affinity);
 153         spin_lock_irqsave(&leon_irq_lock, flags);
 154         oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(cpu));
 155         LEON3_BYPASS_STORE_PA(LEON_IMASK(cpu), (oldmask | mask));
 156         spin_unlock_irqrestore(&leon_irq_lock, flags);
 157 }
 158
 159 static void leon_mask_irq(struct irq_data *data)
 160 {
 161         unsigned long mask, oldmask, flags;
 162         int cpu;
 163
 164         mask = (unsigned long)data->chip_data;
 165         cpu = irq_choose_cpu(data->affinity);
 166         spin_lock_irqsave(&leon_irq_lock, flags);
 167         oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(cpu));
 168         LEON3_BYPASS_STORE_PA(LEON_IMASK(cpu), (oldmask & ~mask));
 169         spin_unlock_irqrestore(&leon_irq_lock, flags);
 170 }
 171
 172 static unsigned int leon_startup_irq(struct irq_data *data)
 173 {
 174         irq_link(data->irq);
 175         leon_unmask_irq(data);
 176         return 0;
 177 }
 178
 179 static void leon_shutdown_irq(struct irq_data *data)
 180 {
 181         leon_mask_irq(data);
 182         irq_unlink(data->irq);
 183 }
 184
 185 /* Used by external level sensitive IRQ handlers on the LEON: ACK IRQ ctrl */
 186 static void leon_eoi_irq(struct irq_data *data)
 187 {
 188         unsigned long mask = (unsigned long)data->chip_data;
 189
 190         if (mask & LEON_DO_ACK_HW)
 191                 LEON3_BYPASS_STORE_PA(LEON_IACK, mask & ~LEON_DO_ACK_HW);
 192 }
 193
 194 static struct irq_chip leon_irq = {
 195         .name                   = "leon",
 196         .irq_startup            = leon_startup_irq,
 197         .irq_shutdown           = leon_shutdown_irq,
 198         .irq_mask               = leon_mask_irq,
 199         .irq_unmask             = leon_unmask_irq,
 200         .irq_eoi                = leon_eoi_irq,
 201         .irq_set_affinity       = leon_set_affinity,
 202 };
 203
 204 /*
 205  * Build a LEON IRQ for the edge triggered LEON IRQ controller:
 206  *  Edge (normal) IRQ           - handle_simple_irq, ack=DONT-CARE, never ack
 207  *  Level IRQ (PCI|Level-GPIO)  - handle_fasteoi_irq, ack=1, ack after ISR
 208  *  Per-CPU Edge                - handle_percpu_irq, ack=0
 209  */
 210 unsigned int leon_build_device_irq(unsigned int real_irq,
 211                                     irq_flow_handler_t flow_handler,
 212                                     const char *name, int do_ack)
 213 {
 214         unsigned int irq;
 215         unsigned long mask;
 216
 217         irq = 0;
 218         mask = leon_get_irqmask(real_irq);
 219         if (mask == 0)
 220                 goto out;
 221
 222         irq = irq_alloc(real_irq, real_irq);
 223         if (irq == 0)
 224                 goto out;
 225
 226         if (do_ack)
 227                 mask |= LEON_DO_ACK_HW;
 228
 229         irq_set_chip_and_handler_name(irq, &leon_irq,
 230                                       flow_handler, name);
 231         irq_set_chip_data(irq, (void *)mask);
 232
 233 out:
 234         return irq;
 235 }
 236
 237 static unsigned int _leon_build_device_irq(struct platform_device *op,
 238                                            unsigned int real_irq)
 239 {
 240         return leon_build_device_irq(real_irq, handle_simple_irq, "edge", 0);
 241 }
 242
 243 void leon_update_virq_handling(unsigned int virq,
 244                               irq_flow_handler_t flow_handler,
 245                               const char *name, int do_ack)
 246 {
 247         unsigned long mask = (unsigned long)irq_get_chip_data(virq);
 248
 249         mask &= ~LEON_DO_ACK_HW;
 250         if (do_ack)
 251                 mask |= LEON_DO_ACK_HW;
 252
 253         irq_set_chip_and_handler_name(virq, &leon_irq,
 254                                       flow_handler, name);
 255         irq_set_chip_data(virq, (void *)mask);
 256 }
 257
 258 static u32 leon_cycles_offset(void)
 259 {
 260         u32 rld, val, off;
 261         rld = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].rld);
 262         val = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].val);
 263         off = rld - val;
 264         return rld - val;
 265 }
 266
 267 #ifdef CONFIG_SMP
 268
 269 /* smp clockevent irq */
 270 irqreturn_t leon_percpu_timer_ce_interrupt(int irq, void *unused)
 271 {
 272         struct clock_event_device *ce;
 273         int cpu = smp_processor_id();
 274
 275         leon_clear_profile_irq(cpu);
 276
 277         ce = &per_cpu(sparc32_clockevent, cpu);
 278
 279         irq_enter();
 280         if (ce->event_handler)
 281                 ce->event_handler(ce);
 282         irq_exit();
 283
 284         return IRQ_HANDLED;
 285 }
 286
 287 #endif /* CONFIG_SMP */
 288
 289 void __init leon_init_timers(void)
 290 {
 291         int irq, eirq;
 292         struct device_node *rootnp, *np, *nnp;
 293         struct property *pp;
 294         int len;
 295         int icsel;
 296         int ampopts;
 297         int err;
 298
 299         sparc_config.get_cycles_offset = leon_cycles_offset;
 300         sparc_config.cs_period = 1000000 / HZ;
 301         sparc_config.features |= FEAT_L10_CLOCKSOURCE;
 302
 303 #ifndef CONFIG_SMP
 304         sparc_config.features |= FEAT_L10_CLOCKEVENT;
 305 #endif
 306
 307         leondebug_irq_disable = 0;
 308         leon_debug_irqout = 0;
 309         master_l10_counter = (unsigned int *)&dummy_master_l10_counter;
 310         dummy_master_l10_counter = 0;
 311
 312         rootnp = of_find_node_by_path("/ambapp0");
 313         if (!rootnp)
 314                 goto bad;
 315
 316         /* Find System ID: GRLIB build ID and optional CHIP ID */
 317         pp = of_find_property(rootnp, "systemid", &len);
 318         if (pp)
 319                 amba_system_id = *(unsigned long *)pp->value;
 320
 321         /* Find IRQMP IRQ Controller Registers base adr otherwise bail out */
 322         np = of_find_node_by_name(rootnp, "GAISLER_IRQMP");
 323         if (!np) {
 324                 np = of_find_node_by_name(rootnp, "01_00d");
 325                 if (!np)
 326                         goto bad;
 327         }
 328         pp = of_find_property(np, "reg", &len);
 329         if (!pp)
 330                 goto bad;
 331         leon3_irqctrl_regs = *(struct leon3_irqctrl_regs_map **)pp->value;
 332
 333         /* Find GPTIMER Timer Registers base address otherwise bail out. */
 334         nnp = rootnp;
 335         do {
 336                 np = of_find_node_by_name(nnp, "GAISLER_GPTIMER");
 337                 if (!np) {
 338                         np = of_find_node_by_name(nnp, "01_011");
 339                         if (!np)
 340                                 goto bad;
 341                 }
 342
 343                 ampopts = 0;
 344                 pp = of_find_property(np, "ampopts", &len);
 345                 if (pp) {
 346                         ampopts = *(int *)pp->value;
 347                         if (ampopts == 0) {
 348                                 /* Skip this instance, resource already
 349                                  * allocated by other OS */
 350                                 nnp = np;
 351                                 continue;
 352                         }
 353                 }
 354
 355                 /* Select Timer-Instance on Timer Core. Default is zero */
 356                 leon3_gptimer_idx = ampopts & 0x7;
 357
 358                 pp = of_find_property(np, "reg", &len);
 359                 if (pp)
 360                         leon3_gptimer_regs = *(struct leon3_gptimer_regs_map **)
 361                                                 pp->value;
 362                 pp = of_find_property(np, "interrupts", &len);
 363                 if (pp)
 364                         leon3_gptimer_irq = *(unsigned int *)pp->value;
 365         } while (0);
 366
 367         if (!(leon3_gptimer_regs && leon3_irqctrl_regs && leon3_gptimer_irq))
 368                 goto bad;
 369
 370         LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].val, 0);
 371         LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].rld,
 372                                 (((1000000 / HZ) - 1)));
 373         LEON3_BYPASS_STORE_PA(
 374                         &leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl, 0);
 375
 376 #ifdef CONFIG_SMP
 377         leon3_ticker_irq = leon3_gptimer_irq + 1 + leon3_gptimer_idx;
 378
 379         if (!(LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->config) &
 380               (1<<LEON3_GPTIMER_SEPIRQ))) {
 381                 printk(KERN_ERR "timer not configured with separate irqs\n");
 382                 BUG();
 383         }
 384
 385         LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx+1].val,
 386                                 0);
 387         LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx+1].rld,
 388                                 (((1000000/HZ) - 1)));
 389         LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx+1].ctrl,
 390                                 0);
 391 #endif
 392
 393         /*
 394          * The IRQ controller may (if implemented) consist of multiple
 395          * IRQ controllers, each mapped on a 4Kb boundary.
 396          * Each CPU may be routed to different IRQCTRLs, however
 397          * we assume that all CPUs (in SMP system) is routed to the
 398          * same IRQ Controller, and for non-SMP only one IRQCTRL is
 399          * accessed anyway.
 400          * In AMP systems, Linux must run on CPU0 for the time being.
 401          */
 402         icsel = LEON3_BYPASS_LOAD_PA(&leon3_irqctrl_regs->icsel[boot_cpu_id/8]);
 403         icsel = (icsel >> ((7 - (boot_cpu_id&0x7)) * 4)) & 0xf;
 404         leon3_irqctrl_regs += icsel;
 405
 406         /* Mask all IRQs on boot-cpu IRQ controller */
 407         LEON3_BYPASS_STORE_PA(&leon3_irqctrl_regs->mask[boot_cpu_id], 0);
 408
 409         /* Probe extended IRQ controller */
 410         eirq = (LEON3_BYPASS_LOAD_PA(&leon3_irqctrl_regs->mpstatus)
 411                 >> 16) & 0xf;
 412         if (eirq != 0)
 413                 leon_eirq_setup(eirq);
 414
 415         irq = _leon_build_device_irq(NULL, leon3_gptimer_irq+leon3_gptimer_idx);
 416         err = request_irq(irq, timer_interrupt, IRQF_TIMER, "timer", NULL);
 417         if (err) {
 418                 printk(KERN_ERR "unable to attach timer IRQ%d\n", irq);
 419                 prom_halt();
 420         }
 421
 422 #ifdef CONFIG_SMP
 423         {
 424                 unsigned long flags;
 425
 426                 /*
 427                  * In SMP, sun4m adds a IPI handler to IRQ trap handler that
 428                  * LEON never must take, sun4d and LEON overwrites the branch
 429                  * with a NOP.
 430                  */
 431                 local_irq_save(flags);
 432                 patchme_maybe_smp_msg[0] = 0x01000000; /* NOP out the branch */
 433                 local_ops->cache_all();
 434                 local_irq_restore(flags);
 435         }
 436 #endif
 437
 438         LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl,
 439                               LEON3_GPTIMER_EN |
 440                               LEON3_GPTIMER_RL |
 441                               LEON3_GPTIMER_LD |
 442                               LEON3_GPTIMER_IRQEN);
 443
 444 #ifdef CONFIG_SMP
 445         /* Install per-cpu IRQ handler for broadcasted ticker */
 446         irq = leon_build_device_irq(leon3_ticker_irq, handle_percpu_irq,
 447                                     "per-cpu", 0);
 448         err = request_irq(irq, leon_percpu_timer_ce_interrupt,
 449                           IRQF_PERCPU | IRQF_TIMER, "ticker",
 450                           NULL);
 451         if (err) {
 452                 printk(KERN_ERR "unable to attach ticker IRQ%d\n", irq);
 453                 prom_halt();
 454         }
 455
 456         LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx+1].ctrl,
 457                               LEON3_GPTIMER_EN |
 458                               LEON3_GPTIMER_RL |
 459                               LEON3_GPTIMER_LD |
 460                               LEON3_GPTIMER_IRQEN);
 461 #endif
 462         return;
 463 bad:
 464         printk(KERN_ERR "No Timer/irqctrl found\n");
 465         BUG();
 466         return;
 467 }
 468
 469 static void leon_clear_clock_irq(void)
 470 {
 471 }
 472
 473 static void leon_load_profile_irq(int cpu, unsigned int limit)
 474 {
 475 }
 476
 477 void __init leon_trans_init(struct device_node *dp)
 478 {
 479         if (strcmp(dp->type, "cpu") == 0 && strcmp(dp->name, "<NULL>") == 0) {
 480                 struct property *p;
 481                 p = of_find_property(dp, "mid", (void *)0);
 482                 if (p) {
 483                         int mid;
 484                         dp->name = prom_early_alloc(5 + 1);
 485                         memcpy(&mid, p->value, p->length);
 486                         sprintf((char *)dp->name, "cpu%.2d", mid);
 487                 }
 488         }
 489 }
 490
 491 #ifdef CONFIG_SMP
 492 void leon_clear_profile_irq(int cpu)
 493 {
 494 }
 495
 496 void leon_enable_irq_cpu(unsigned int irq_nr, unsigned int cpu)
 497 {
 498         unsigned long mask, flags, *addr;
 499         mask = leon_get_irqmask(irq_nr);
 500         spin_lock_irqsave(&leon_irq_lock, flags);
 501         addr = (unsigned long *)LEON_IMASK(cpu);
 502         LEON3_BYPASS_STORE_PA(addr, (LEON3_BYPASS_LOAD_PA(addr) | mask));
 503         spin_unlock_irqrestore(&leon_irq_lock, flags);
 504 }
 505
 506 #endif
 507
 508 void __init leon_init_IRQ(void)
 509 {
 510         sparc_config.init_timers      = leon_init_timers;
 511         sparc_config.build_device_irq = _leon_build_device_irq;
 512         sparc_config.clock_rate       = 1000000;
 513         sparc_config.clear_clock_irq  = leon_clear_clock_irq;
 514         sparc_config.load_profile_irq = leon_load_profile_irq;
 515 }