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 volatile u32 dummy_master_l10_counter;
  36 unsigned long amba_system_id;
  37 static DEFINE_SPINLOCK(leon_irq_lock);
  38
  39 static unsigned long leon3_gptimer_idx; /* Timer Index (0..6) within Timer Core */
  40 static unsigned long leon3_gptimer_ackmask; /* For clearing pending bit */
  41 unsigned long leon3_gptimer_irq; /* interrupt controller irq number */
  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(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 static 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(irq_data_get_affinity_mask(data));
 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(irq_data_get_affinity_mask(data));
 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(irq_data_get_affinity_mask(data));
 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=DON'T-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         struct irq_desc *desc;
 217
 218         irq = 0;
 219         mask = leon_get_irqmask(real_irq);
 220         if (mask == 0)
 221                 goto out;
 222
 223         irq = irq_alloc(real_irq, real_irq);
 224         if (irq == 0)
 225                 goto out;
 226
 227         if (do_ack)
 228                 mask |= LEON_DO_ACK_HW;
 229
 230         desc = irq_to_desc(irq);
 231         if (!desc || !desc->handle_irq || desc->handle_irq == handle_bad_irq) {
 232                 irq_set_chip_and_handler_name(irq, &leon_irq,
 233                                               flow_handler, name);
 234                 irq_set_chip_data(irq, (void *)mask);
 235         }
 236
 237 out:
 238         return irq;
 239 }
 240
 241 static unsigned int _leon_build_device_irq(struct platform_device *op,
 242                                            unsigned int real_irq)
 243 {
 244         return leon_build_device_irq(real_irq, handle_simple_irq, "edge", 0);
 245 }
 246
 247 void leon_update_virq_handling(unsigned int virq,
 248                               irq_flow_handler_t flow_handler,
 249                               const char *name, int do_ack)
 250 {
 251         unsigned long mask = (unsigned long)irq_get_chip_data(virq);
 252
 253         mask &= ~LEON_DO_ACK_HW;
 254         if (do_ack)
 255                 mask |= LEON_DO_ACK_HW;
 256
 257         irq_set_chip_and_handler_name(virq, &leon_irq,
 258                                       flow_handler, name);
 259         irq_set_chip_data(virq, (void *)mask);
 260 }
 261
 262 static u32 leon_cycles_offset(void)
 263 {
 264         u32 rld, val, ctrl, off;
 265
 266         rld = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].rld);
 267         val = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].val);
 268         ctrl = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl);
 269         if (LEON3_GPTIMER_CTRL_ISPENDING(ctrl)) {
 270                 val = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].val);
 271                 off = 2 * rld - val;
 272         } else {
 273                 off = rld - val;
 274         }
 275
 276         return off;
 277 }
 278
 279 #ifdef CONFIG_SMP
 280
 281 /* smp clockevent irq */
 282 static irqreturn_t leon_percpu_timer_ce_interrupt(int irq, void *unused)
 283 {
 284         struct clock_event_device *ce;
 285         int cpu = smp_processor_id();
 286
 287         leon_clear_profile_irq(cpu);
 288
 289         if (cpu == boot_cpu_id)
 290                 timer_interrupt(irq, NULL);
 291
 292         ce = &per_cpu(sparc32_clockevent, cpu);
 293
 294         irq_enter();
 295         if (ce->event_handler)
 296                 ce->event_handler(ce);
 297         irq_exit();
 298
 299         return IRQ_HANDLED;
 300 }
 301
 302 #endif /* CONFIG_SMP */
 303
 304 void __init leon_init_timers(void)
 305 {
 306         int irq, eirq;
 307         struct device_node *rootnp, *np, *nnp;
 308         struct property *pp;
 309         int len;
 310         int icsel;
 311         int ampopts;
 312         int err;
 313         u32 config;
 314         u32 ctrl;
 315
 316         sparc_config.get_cycles_offset = leon_cycles_offset;
 317         sparc_config.cs_period = 1000000 / HZ;
 318         sparc_config.features |= FEAT_L10_CLOCKSOURCE;
 319
 320 #ifndef CONFIG_SMP
 321         sparc_config.features |= FEAT_L10_CLOCKEVENT;
 322 #endif
 323
 324         leondebug_irq_disable = 0;
 325         leon_debug_irqout = 0;
 326         master_l10_counter = (u32 __iomem *)&dummy_master_l10_counter;
 327         dummy_master_l10_counter = 0;
 328
 329         rootnp = of_find_node_by_path("/ambapp0");
 330         if (!rootnp)
 331                 goto bad;
 332
 333         /* Find System ID: GRLIB build ID and optional CHIP ID */
 334         pp = of_find_property(rootnp, "systemid", &len);
 335         if (pp)
 336                 amba_system_id = *(unsigned long *)pp->value;
 337
 338         /* Find IRQMP IRQ Controller Registers base adr otherwise bail out */
 339         np = of_find_node_by_name(rootnp, "GAISLER_IRQMP");
 340         if (!np) {
 341                 np = of_find_node_by_name(rootnp, "01_00d");
 342                 if (!np)
 343                         goto bad;
 344         }
 345         pp = of_find_property(np, "reg", &len);
 346         if (!pp)
 347                 goto bad;
 348         leon3_irqctrl_regs = *(struct leon3_irqctrl_regs_map **)pp->value;
 349
 350         /* Find GPTIMER Timer Registers base address otherwise bail out. */
 351         nnp = rootnp;
 352         do {
 353                 np = of_find_node_by_name(nnp, "GAISLER_GPTIMER");
 354                 if (!np) {
 355                         np = of_find_node_by_name(nnp, "01_011");
 356                         if (!np)
 357                                 goto bad;
 358                 }
 359
 360                 ampopts = 0;
 361                 pp = of_find_property(np, "ampopts", &len);
 362                 if (pp) {
 363                         ampopts = *(int *)pp->value;
 364                         if (ampopts == 0) {
 365                                 /* Skip this instance, resource already
 366                                  * allocated by other OS */
 367                                 nnp = np;
 368                                 continue;
 369                         }
 370                 }
 371
 372                 /* Select Timer-Instance on Timer Core. Default is zero */
 373                 leon3_gptimer_idx = ampopts & 0x7;
 374
 375                 pp = of_find_property(np, "reg", &len);
 376                 if (pp)
 377                         leon3_gptimer_regs = *(struct leon3_gptimer_regs_map **)
 378                                                 pp->value;
 379                 pp = of_find_property(np, "interrupts", &len);
 380                 if (pp)
 381                         leon3_gptimer_irq = *(unsigned int *)pp->value;
 382         } while (0);
 383
 384         if (!(leon3_gptimer_regs && leon3_irqctrl_regs && leon3_gptimer_irq))
 385                 goto bad;
 386
 387         ctrl = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl);
 388         LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl,
 389                               ctrl | LEON3_GPTIMER_CTRL_PENDING);
 390         ctrl = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl);
 391
 392         if ((ctrl & LEON3_GPTIMER_CTRL_PENDING) != 0)
 393                 leon3_gptimer_ackmask = ~LEON3_GPTIMER_CTRL_PENDING;
 394         else
 395                 leon3_gptimer_ackmask = ~0;
 396
 397         LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].val, 0);
 398         LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].rld,
 399                                 (((1000000 / HZ) - 1)));
 400         LEON3_BYPASS_STORE_PA(
 401                         &leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl, 0);
 402
 403         /*
 404          * The IRQ controller may (if implemented) consist of multiple
 405          * IRQ controllers, each mapped on a 4Kb boundary.
 406          * Each CPU may be routed to different IRQCTRLs, however
 407          * we assume that all CPUs (in SMP system) is routed to the
 408          * same IRQ Controller, and for non-SMP only one IRQCTRL is
 409          * accessed anyway.
 410          * In AMP systems, Linux must run on CPU0 for the time being.
 411          */
 412         icsel = LEON3_BYPASS_LOAD_PA(&leon3_irqctrl_regs->icsel[boot_cpu_id/8]);
 413         icsel = (icsel >> ((7 - (boot_cpu_id&0x7)) * 4)) & 0xf;
 414         leon3_irqctrl_regs += icsel;
 415
 416         /* Mask all IRQs on boot-cpu IRQ controller */
 417         LEON3_BYPASS_STORE_PA(&leon3_irqctrl_regs->mask[boot_cpu_id], 0);
 418
 419         /* Probe extended IRQ controller */
 420         eirq = (LEON3_BYPASS_LOAD_PA(&leon3_irqctrl_regs->mpstatus)
 421                 >> 16) & 0xf;
 422         if (eirq != 0)
 423                 leon_eirq_setup(eirq);
 424
 425 #ifdef CONFIG_SMP
 426         {
 427                 unsigned long flags;
 428
 429                 /*
 430                  * In SMP, sun4m adds a IPI handler to IRQ trap handler that
 431                  * LEON never must take, sun4d and LEON overwrites the branch
 432                  * with a NOP.
 433                  */
 434                 local_irq_save(flags);
 435                 patchme_maybe_smp_msg[0] = 0x01000000; /* NOP out the branch */
 436                 local_ops->cache_all();
 437                 local_irq_restore(flags);
 438         }
 439 #endif
 440
 441         config = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->config);
 442         if (config & (1 << LEON3_GPTIMER_SEPIRQ))
 443                 leon3_gptimer_irq += leon3_gptimer_idx;
 444         else if ((config & LEON3_GPTIMER_TIMERS) > 1)
 445                 pr_warn("GPTIMER uses shared irqs, using other timers of the same core will fail.\n");
 446
 447 #ifdef CONFIG_SMP
 448         /* Install per-cpu IRQ handler for broadcasted ticker */
 449         irq = leon_build_device_irq(leon3_gptimer_irq, handle_percpu_irq,
 450                                     "per-cpu", 0);
 451         err = request_irq(irq, leon_percpu_timer_ce_interrupt,
 452                           IRQF_PERCPU | IRQF_TIMER, "timer", NULL);
 453 #else
 454         irq = _leon_build_device_irq(NULL, leon3_gptimer_irq);
 455         err = request_irq(irq, timer_interrupt, IRQF_TIMER, "timer", NULL);
 456 #endif
 457         if (err) {
 458                 pr_err("Unable to attach timer IRQ%d\n", irq);
 459                 prom_halt();
 460         }
 461         LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl,
 462                               LEON3_GPTIMER_EN |
 463                               LEON3_GPTIMER_RL |
 464                               LEON3_GPTIMER_LD |
 465                               LEON3_GPTIMER_IRQEN);
 466         return;
 467 bad:
 468         printk(KERN_ERR "No Timer/irqctrl found\n");
 469         BUG();
 470         return;
 471 }
 472
 473 static void leon_clear_clock_irq(void)
 474 {
 475         u32 ctrl;
 476
 477         ctrl = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl);
 478         LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl,
 479                               ctrl & leon3_gptimer_ackmask);
 480 }
 481
 482 static void leon_load_profile_irq(int cpu, unsigned int limit)
 483 {
 484 }
 485
 486 void __init leon_trans_init(struct device_node *dp)
 487 {
 488         if (strcmp(dp->type, "cpu") == 0 && strcmp(dp->name, "<NULL>") == 0) {
 489                 struct property *p;
 490                 p = of_find_property(dp, "mid", (void *)0);
 491                 if (p) {
 492                         int mid;
 493                         dp->name = prom_early_alloc(5 + 1);
 494                         memcpy(&mid, p->value, p->length);
 495                         sprintf((char *)dp->name, "cpu%.2d", mid);
 496                 }
 497         }
 498 }
 499
 500 #ifdef CONFIG_SMP
 501 void leon_clear_profile_irq(int cpu)
 502 {
 503 }
 504
 505 void leon_enable_irq_cpu(unsigned int irq_nr, unsigned int cpu)
 506 {
 507         unsigned long mask, flags, *addr;
 508         mask = leon_get_irqmask(irq_nr);
 509         spin_lock_irqsave(&leon_irq_lock, flags);
 510         addr = (unsigned long *)LEON_IMASK(cpu);
 511         LEON3_BYPASS_STORE_PA(addr, (LEON3_BYPASS_LOAD_PA(addr) | mask));
 512         spin_unlock_irqrestore(&leon_irq_lock, flags);
 513 }
 514
 515 #endif
 516
 517 void __init leon_init_IRQ(void)
 518 {
 519         sparc_config.init_timers      = leon_init_timers;
 520         sparc_config.build_device_irq = _leon_build_device_irq;
 521         sparc_config.clock_rate       = 1000000;
 522         sparc_config.clear_clock_irq  = leon_clear_clock_irq;
 523         sparc_config.load_profile_irq = leon_load_profile_irq;
 524 }