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 unsigned 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 unsigned int sparc_leon_eirq;
  42 #define LEON_IMASK(cpu) (&leon3_irqctrl_regs->mask[cpu])
  43 #define LEON_IACK (&leon3_irqctrl_regs->iclear)
  44 #define LEON_DO_ACK_HW 1
  45
  46 /* Return the last ACKed IRQ by the Extended IRQ controller. It has already
  47  * been (automatically) ACKed when the CPU takes the trap.
  48  */
  49 static inline unsigned int leon_eirq_get(int cpu)
  50 {
  51         return LEON3_BYPASS_LOAD_PA(&leon3_irqctrl_regs->intid[cpu]) & 0x1f;
  52 }
  53
  54 /* Handle one or multiple IRQs from the extended interrupt controller */
  55 static void leon_handle_ext_irq(unsigned int irq, struct irq_desc *desc)
  56 {
  57         unsigned int eirq;
  58         struct irq_bucket *p;
  59         int cpu = sparc_leon3_cpuid();
  60
  61         eirq = leon_eirq_get(cpu);
  62         p = irq_map[eirq];
  63         if ((eirq & 0x10) && p && p->irq) /* bit4 tells if IRQ happened */
  64                 generic_handle_irq(p->irq);
  65 }
  66
  67 /* The extended IRQ controller has been found, this function registers it */
  68 void leon_eirq_setup(unsigned int eirq)
  69 {
  70         unsigned long mask, oldmask;
  71         unsigned int veirq;
  72
  73         if (eirq < 1 || eirq > 0xf) {
  74                 printk(KERN_ERR "LEON EXT IRQ NUMBER BAD: %d\n", eirq);
  75                 return;
  76         }
  77
  78         veirq = leon_build_device_irq(eirq, leon_handle_ext_irq, "extirq", 0);
  79
  80         /*
  81          * Unmask the Extended IRQ, the IRQs routed through the Ext-IRQ
  82          * controller have a mask-bit of their own, so this is safe.
  83          */
  84         irq_link(veirq);
  85         mask = 1 << eirq;
  86         oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(boot_cpu_id));
  87         LEON3_BYPASS_STORE_PA(LEON_IMASK(boot_cpu_id), (oldmask | mask));
  88         sparc_leon_eirq = eirq;
  89 }
  90
  91 unsigned long leon_get_irqmask(unsigned int irq)
  92 {
  93         unsigned long mask;
  94
  95         if (!irq || ((irq > 0xf) && !sparc_leon_eirq)
  96             || ((irq > 0x1f) && sparc_leon_eirq)) {
  97                 printk(KERN_ERR
  98                        "leon_get_irqmask: false irq number: %d\n", irq);
  99                 mask = 0;
 100         } else {
 101                 mask = LEON_HARD_INT(irq);
 102         }
 103         return mask;
 104 }
 105
 106 #ifdef CONFIG_SMP
 107 static int irq_choose_cpu(const struct cpumask *affinity)
 108 {
 109         cpumask_t mask;
 110
 111         cpumask_and(&mask, cpu_online_mask, affinity);
 112         if (cpumask_equal(&mask, cpu_online_mask) || cpumask_empty(&mask))
 113                 return boot_cpu_id;
 114         else
 115                 return cpumask_first(&mask);
 116 }
 117 #else
 118 #define irq_choose_cpu(affinity) boot_cpu_id
 119 #endif
 120
 121 static int leon_set_affinity(struct irq_data *data, const struct cpumask *dest,
 122                              bool force)
 123 {
 124         unsigned long mask, oldmask, flags;
 125         int oldcpu, newcpu;
 126
 127         mask = (unsigned long)data->chip_data;
 128         oldcpu = irq_choose_cpu(data->affinity);
 129         newcpu = irq_choose_cpu(dest);
 130
 131         if (oldcpu == newcpu)
 132                 goto out;
 133
 134         /* unmask on old CPU first before enabling on the selected CPU */
 135         spin_lock_irqsave(&leon_irq_lock, flags);
 136         oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(oldcpu));
 137         LEON3_BYPASS_STORE_PA(LEON_IMASK(oldcpu), (oldmask & ~mask));
 138         oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(newcpu));
 139         LEON3_BYPASS_STORE_PA(LEON_IMASK(newcpu), (oldmask | mask));
 140         spin_unlock_irqrestore(&leon_irq_lock, flags);
 141 out:
 142         return IRQ_SET_MASK_OK;
 143 }
 144
 145 static void leon_unmask_irq(struct irq_data *data)
 146 {
 147         unsigned long mask, oldmask, flags;
 148         int cpu;
 149
 150         mask = (unsigned long)data->chip_data;
 151         cpu = irq_choose_cpu(data->affinity);
 152         spin_lock_irqsave(&leon_irq_lock, flags);
 153         oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(cpu));
 154         LEON3_BYPASS_STORE_PA(LEON_IMASK(cpu), (oldmask | mask));
 155         spin_unlock_irqrestore(&leon_irq_lock, flags);
 156 }
 157
 158 static void leon_mask_irq(struct irq_data *data)
 159 {
 160         unsigned long mask, oldmask, flags;
 161         int cpu;
 162
 163         mask = (unsigned long)data->chip_data;
 164         cpu = irq_choose_cpu(data->affinity);
 165         spin_lock_irqsave(&leon_irq_lock, flags);
 166         oldmask = LEON3_BYPASS_LOAD_PA(LEON_IMASK(cpu));
 167         LEON3_BYPASS_STORE_PA(LEON_IMASK(cpu), (oldmask & ~mask));
 168         spin_unlock_irqrestore(&leon_irq_lock, flags);
 169 }
 170
 171 static unsigned int leon_startup_irq(struct irq_data *data)
 172 {
 173         irq_link(data->irq);
 174         leon_unmask_irq(data);
 175         return 0;
 176 }
 177
 178 static void leon_shutdown_irq(struct irq_data *data)
 179 {
 180         leon_mask_irq(data);
 181         irq_unlink(data->irq);
 182 }
 183
 184 /* Used by external level sensitive IRQ handlers on the LEON: ACK IRQ ctrl */
 185 static void leon_eoi_irq(struct irq_data *data)
 186 {
 187         unsigned long mask = (unsigned long)data->chip_data;
 188
 189         if (mask & LEON_DO_ACK_HW)
 190                 LEON3_BYPASS_STORE_PA(LEON_IACK, mask & ~LEON_DO_ACK_HW);
 191 }
 192
 193 static struct irq_chip leon_irq = {
 194         .name                   = "leon",
 195         .irq_startup            = leon_startup_irq,
 196         .irq_shutdown           = leon_shutdown_irq,
 197         .irq_mask               = leon_mask_irq,
 198         .irq_unmask             = leon_unmask_irq,
 199         .irq_eoi                = leon_eoi_irq,
 200         .irq_set_affinity       = leon_set_affinity,
 201 };
 202
 203 /*
 204  * Build a LEON IRQ for the edge triggered LEON IRQ controller:
 205  *  Edge (normal) IRQ           - handle_simple_irq, ack=DONT-CARE, never ack
 206  *  Level IRQ (PCI|Level-GPIO)  - handle_fasteoi_irq, ack=1, ack after ISR
 207  *  Per-CPU Edge                - handle_percpu_irq, ack=0
 208  */
 209 unsigned int leon_build_device_irq(unsigned int real_irq,
 210                                     irq_flow_handler_t flow_handler,
 211                                     const char *name, int do_ack)
 212 {
 213         unsigned int irq;
 214         unsigned long mask;
 215         struct irq_desc *desc;
 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         desc = irq_to_desc(irq);
 230         if (!desc || !desc->handle_irq || desc->handle_irq == handle_bad_irq) {
 231                 irq_set_chip_and_handler_name(irq, &leon_irq,
 232                                               flow_handler, name);
 233                 irq_set_chip_data(irq, (void *)mask);
 234         }
 235
 236 out:
 237         return irq;
 238 }
 239
 240 static unsigned int _leon_build_device_irq(struct platform_device *op,
 241                                            unsigned int real_irq)
 242 {
 243         return leon_build_device_irq(real_irq, handle_simple_irq, "edge", 0);
 244 }
 245
 246 void leon_update_virq_handling(unsigned int virq,
 247                               irq_flow_handler_t flow_handler,
 248                               const char *name, int do_ack)
 249 {
 250         unsigned long mask = (unsigned long)irq_get_chip_data(virq);
 251
 252         mask &= ~LEON_DO_ACK_HW;
 253         if (do_ack)
 254                 mask |= LEON_DO_ACK_HW;
 255
 256         irq_set_chip_and_handler_name(virq, &leon_irq,
 257                                       flow_handler, name);
 258         irq_set_chip_data(virq, (void *)mask);
 259 }
 260
 261 static u32 leon_cycles_offset(void)
 262 {
 263         u32 rld, val, off;
 264         rld = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].rld);
 265         val = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].val);
 266         off = rld - val;
 267         return rld - val;
 268 }
 269
 270 #ifdef CONFIG_SMP
 271
 272 /* smp clockevent irq */
 273 irqreturn_t leon_percpu_timer_ce_interrupt(int irq, void *unused)
 274 {
 275         struct clock_event_device *ce;
 276         int cpu = smp_processor_id();
 277
 278         leon_clear_profile_irq(cpu);
 279
 280         if (cpu == boot_cpu_id)
 281                 timer_interrupt(irq, NULL);
 282
 283         ce = &per_cpu(sparc32_clockevent, cpu);
 284
 285         irq_enter();
 286         if (ce->event_handler)
 287                 ce->event_handler(ce);
 288         irq_exit();
 289
 290         return IRQ_HANDLED;
 291 }
 292
 293 #endif /* CONFIG_SMP */
 294
 295 void __init leon_init_timers(void)
 296 {
 297         int irq, eirq;
 298         struct device_node *rootnp, *np, *nnp;
 299         struct property *pp;
 300         int len;
 301         int icsel;
 302         int ampopts;
 303         int err;
 304         u32 config;
 305
 306         sparc_config.get_cycles_offset = leon_cycles_offset;
 307         sparc_config.cs_period = 1000000 / HZ;
 308         sparc_config.features |= FEAT_L10_CLOCKSOURCE;
 309
 310 #ifndef CONFIG_SMP
 311         sparc_config.features |= FEAT_L10_CLOCKEVENT;
 312 #endif
 313
 314         leondebug_irq_disable = 0;
 315         leon_debug_irqout = 0;
 316         master_l10_counter =
 317                 (unsigned int __iomem *)&dummy_master_l10_counter;
 318         dummy_master_l10_counter = 0;
 319
 320         rootnp = of_find_node_by_path("/ambapp0");
 321         if (!rootnp)
 322                 goto bad;
 323
 324         /* Find System ID: GRLIB build ID and optional CHIP ID */
 325         pp = of_find_property(rootnp, "systemid", &len);
 326         if (pp)
 327                 amba_system_id = *(unsigned long *)pp->value;
 328
 329         /* Find IRQMP IRQ Controller Registers base adr otherwise bail out */
 330         np = of_find_node_by_name(rootnp, "GAISLER_IRQMP");
 331         if (!np) {
 332                 np = of_find_node_by_name(rootnp, "01_00d");
 333                 if (!np)
 334                         goto bad;
 335         }
 336         pp = of_find_property(np, "reg", &len);
 337         if (!pp)
 338                 goto bad;
 339         leon3_irqctrl_regs = *(struct leon3_irqctrl_regs_map **)pp->value;
 340
 341         /* Find GPTIMER Timer Registers base address otherwise bail out. */
 342         nnp = rootnp;
 343         do {
 344                 np = of_find_node_by_name(nnp, "GAISLER_GPTIMER");
 345                 if (!np) {
 346                         np = of_find_node_by_name(nnp, "01_011");
 347                         if (!np)
 348                                 goto bad;
 349                 }
 350
 351                 ampopts = 0;
 352                 pp = of_find_property(np, "ampopts", &len);
 353                 if (pp) {
 354                         ampopts = *(int *)pp->value;
 355                         if (ampopts == 0) {
 356                                 /* Skip this instance, resource already
 357                                  * allocated by other OS */
 358                                 nnp = np;
 359                                 continue;
 360                         }
 361                 }
 362
 363                 /* Select Timer-Instance on Timer Core. Default is zero */
 364                 leon3_gptimer_idx = ampopts & 0x7;
 365
 366                 pp = of_find_property(np, "reg", &len);
 367                 if (pp)
 368                         leon3_gptimer_regs = *(struct leon3_gptimer_regs_map **)
 369                                                 pp->value;
 370                 pp = of_find_property(np, "interrupts", &len);
 371                 if (pp)
 372                         leon3_gptimer_irq = *(unsigned int *)pp->value;
 373         } while (0);
 374
 375         if (!(leon3_gptimer_regs && leon3_irqctrl_regs && leon3_gptimer_irq))
 376                 goto bad;
 377
 378         LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].val, 0);
 379         LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].rld,
 380                                 (((1000000 / HZ) - 1)));
 381         LEON3_BYPASS_STORE_PA(
 382                         &leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl, 0);
 383
 384         /*
 385          * The IRQ controller may (if implemented) consist of multiple
 386          * IRQ controllers, each mapped on a 4Kb boundary.
 387          * Each CPU may be routed to different IRQCTRLs, however
 388          * we assume that all CPUs (in SMP system) is routed to the
 389          * same IRQ Controller, and for non-SMP only one IRQCTRL is
 390          * accessed anyway.
 391          * In AMP systems, Linux must run on CPU0 for the time being.
 392          */
 393         icsel = LEON3_BYPASS_LOAD_PA(&leon3_irqctrl_regs->icsel[boot_cpu_id/8]);
 394         icsel = (icsel >> ((7 - (boot_cpu_id&0x7)) * 4)) & 0xf;
 395         leon3_irqctrl_regs += icsel;
 396
 397         /* Mask all IRQs on boot-cpu IRQ controller */
 398         LEON3_BYPASS_STORE_PA(&leon3_irqctrl_regs->mask[boot_cpu_id], 0);
 399
 400         /* Probe extended IRQ controller */
 401         eirq = (LEON3_BYPASS_LOAD_PA(&leon3_irqctrl_regs->mpstatus)
 402                 >> 16) & 0xf;
 403         if (eirq != 0)
 404                 leon_eirq_setup(eirq);
 405
 406 #ifdef CONFIG_SMP
 407         {
 408                 unsigned long flags;
 409
 410                 /*
 411                  * In SMP, sun4m adds a IPI handler to IRQ trap handler that
 412                  * LEON never must take, sun4d and LEON overwrites the branch
 413                  * with a NOP.
 414                  */
 415                 local_irq_save(flags);
 416                 patchme_maybe_smp_msg[0] = 0x01000000; /* NOP out the branch */
 417                 local_ops->cache_all();
 418                 local_irq_restore(flags);
 419         }
 420 #endif
 421
 422         config = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->config);
 423         if (config & (1 << LEON3_GPTIMER_SEPIRQ))
 424                 leon3_gptimer_irq += leon3_gptimer_idx;
 425         else if ((config & LEON3_GPTIMER_TIMERS) > 1)
 426                 pr_warn("GPTIMER uses shared irqs, using other timers of the same core will fail.\n");
 427
 428 #ifdef CONFIG_SMP
 429         /* Install per-cpu IRQ handler for broadcasted ticker */
 430         irq = leon_build_device_irq(leon3_gptimer_irq, handle_percpu_irq,
 431                                     "per-cpu", 0);
 432         err = request_irq(irq, leon_percpu_timer_ce_interrupt,
 433                           IRQF_PERCPU | IRQF_TIMER, "timer", NULL);
 434 #else
 435         irq = _leon_build_device_irq(NULL, leon3_gptimer_irq);
 436         err = request_irq(irq, timer_interrupt, IRQF_TIMER, "timer", NULL);
 437 #endif
 438         if (err) {
 439                 pr_err("Unable to attach timer IRQ%d\n", irq);
 440                 prom_halt();
 441         }
 442         LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl,
 443                               LEON3_GPTIMER_EN |
 444                               LEON3_GPTIMER_RL |
 445                               LEON3_GPTIMER_LD |
 446                               LEON3_GPTIMER_IRQEN);
 447         return;
 448 bad:
 449         printk(KERN_ERR "No Timer/irqctrl found\n");
 450         BUG();
 451         return;
 452 }
 453
 454 static void leon_clear_clock_irq(void)
 455 {
 456 }
 457
 458 static void leon_load_profile_irq(int cpu, unsigned int limit)
 459 {
 460 }
 461
 462 void __init leon_trans_init(struct device_node *dp)
 463 {
 464         if (strcmp(dp->type, "cpu") == 0 && strcmp(dp->name, "<NULL>") == 0) {
 465                 struct property *p;
 466                 p = of_find_property(dp, "mid", (void *)0);
 467                 if (p) {
 468                         int mid;
 469                         dp->name = prom_early_alloc(5 + 1);
 470                         memcpy(&mid, p->value, p->length);
 471                         sprintf((char *)dp->name, "cpu%.2d", mid);
 472                 }
 473         }
 474 }
 475
 476 #ifdef CONFIG_SMP
 477 void leon_clear_profile_irq(int cpu)
 478 {
 479 }
 480
 481 void leon_enable_irq_cpu(unsigned int irq_nr, unsigned int cpu)
 482 {
 483         unsigned long mask, flags, *addr;
 484         mask = leon_get_irqmask(irq_nr);
 485         spin_lock_irqsave(&leon_irq_lock, flags);
 486         addr = (unsigned long *)LEON_IMASK(cpu);
 487         LEON3_BYPASS_STORE_PA(addr, (LEON3_BYPASS_LOAD_PA(addr) | mask));
 488         spin_unlock_irqrestore(&leon_irq_lock, flags);
 489 }
 490
 491 #endif
 492
 493 void __init leon_init_IRQ(void)
 494 {
 495         sparc_config.init_timers      = leon_init_timers;
 496         sparc_config.build_device_irq = _leon_build_device_irq;
 497         sparc_config.clock_rate       = 1000000;
 498         sparc_config.clear_clock_irq  = leon_clear_clock_irq;
 499         sparc_config.load_profile_irq = leon_load_profile_irq;
 500 }