arch/sparc/kernel/leon_kernel.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) 2009 Daniel Hellstrom (daniel@gaisler.com) Aeroflex Gaisler AB
   4  * Copyright (C) 2009 Konrad Eisele (konrad@gaisler.com) Aeroflex Gaisler AB
   5  */
   6
   7 #include <linux/kernel.h>
   8 #include <linux/errno.h>
   9 #include <linux/mutex.h>
  10 #include <linux/of.h>
  11 #include <linux/interrupt.h>
  12 #include <linux/clocksource.h>
  13 #include <linux/clockchips.h>
  14
  15 #include <asm/oplib.h>
  16 #include <asm/timer.h>
  17 #include <asm/prom.h>
  18 #include <asm/leon.h>
  19 #include <asm/leon_amba.h>
  20 #include <asm/traps.h>
  21 #include <asm/cacheflush.h>
  22 #include <asm/smp.h>
  23 #include <asm/setup.h>
  24
  25 #include "kernel.h"
  26 #include "prom.h"
  27 #include "irq.h"
  28
  29 struct leon3_irqctrl_regs_map *leon3_irqctrl_regs; /* interrupt controller base address */
  30 struct leon3_gptimer_regs_map *leon3_gptimer_regs; /* timer controller base address */
  31
  32 int leondebug_irq_disable;
  33 int leon_debug_irqout;
  34 static volatile u32 dummy_master_l10_counter;
  35 unsigned long amba_system_id;
  36 static DEFINE_SPINLOCK(leon_irq_lock);
  37
  38 static unsigned long leon3_gptimer_idx; /* Timer Index (0..6) within Timer Core */
  39 static unsigned long leon3_gptimer_ackmask; /* For clearing pending bit */
  40 unsigned long leon3_gptimer_irq; /* interrupt controller irq number */
  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(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 static 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         unsigned int cpu = cpumask_first_and(affinity, cpu_online_mask);
 110
 111         if (cpumask_subset(cpu_online_mask, affinity) || cpu >= nr_cpu_ids)
 112                 return boot_cpu_id;
 113         else
 114                 return cpu;
 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(irq_data_get_affinity_mask(data));
 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(irq_data_get_affinity_mask(data));
 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(irq_data_get_affinity_mask(data));
 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=DON'T-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         struct irq_desc *desc;
 215
 216         irq = 0;
 217         mask = leon_get_irqmask(real_irq);
 218         if (mask == 0)
 219                 goto out;
 220
 221         irq = irq_alloc(real_irq, real_irq);
 222         if (irq == 0)
 223                 goto out;
 224
 225         if (do_ack)
 226                 mask |= LEON_DO_ACK_HW;
 227
 228         desc = irq_to_desc(irq);
 229         if (!desc || !desc->handle_irq || desc->handle_irq == handle_bad_irq) {
 230                 irq_set_chip_and_handler_name(irq, &leon_irq,
 231                                               flow_handler, name);
 232                 irq_set_chip_data(irq, (void *)mask);
 233         }
 234
 235 out:
 236         return irq;
 237 }
 238
 239 static unsigned int _leon_build_device_irq(struct platform_device *op,
 240                                            unsigned int real_irq)
 241 {
 242         return leon_build_device_irq(real_irq, handle_simple_irq, "edge", 0);
 243 }
 244
 245 void leon_update_virq_handling(unsigned int virq,
 246                               irq_flow_handler_t flow_handler,
 247                               const char *name, int do_ack)
 248 {
 249         unsigned long mask = (unsigned long)irq_get_chip_data(virq);
 250
 251         mask &= ~LEON_DO_ACK_HW;
 252         if (do_ack)
 253                 mask |= LEON_DO_ACK_HW;
 254
 255         irq_set_chip_and_handler_name(virq, &leon_irq,
 256                                       flow_handler, name);
 257         irq_set_chip_data(virq, (void *)mask);
 258 }
 259
 260 static u32 leon_cycles_offset(void)
 261 {
 262         u32 rld, val, ctrl, off;
 263
 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         ctrl = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl);
 267         if (LEON3_GPTIMER_CTRL_ISPENDING(ctrl)) {
 268                 val = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].val);
 269                 off = 2 * rld - val;
 270         } else {
 271                 off = rld - val;
 272         }
 273
 274         return off;
 275 }
 276
 277 #ifdef CONFIG_SMP
 278
 279 /* smp clockevent irq */
 280 static irqreturn_t leon_percpu_timer_ce_interrupt(int irq, void *unused)
 281 {
 282         struct clock_event_device *ce;
 283         int cpu = smp_processor_id();
 284
 285         leon_clear_profile_irq(cpu);
 286
 287         if (cpu == boot_cpu_id)
 288                 timer_interrupt(irq, NULL);
 289
 290         ce = &per_cpu(sparc32_clockevent, cpu);
 291
 292         irq_enter();
 293         if (ce->event_handler)
 294                 ce->event_handler(ce);
 295         irq_exit();
 296
 297         return IRQ_HANDLED;
 298 }
 299
 300 #endif /* CONFIG_SMP */
 301
 302 void __init leon_init_timers(void)
 303 {
 304         int irq, eirq;
 305         struct device_node *rootnp, *np, *nnp;
 306         struct property *pp;
 307         int len;
 308         int icsel;
 309         int ampopts;
 310         int err;
 311         u32 config;
 312         u32 ctrl;
 313
 314         sparc_config.get_cycles_offset = leon_cycles_offset;
 315         sparc_config.cs_period = 1000000 / HZ;
 316         sparc_config.features |= FEAT_L10_CLOCKSOURCE;
 317
 318 #ifndef CONFIG_SMP
 319         sparc_config.features |= FEAT_L10_CLOCKEVENT;
 320 #endif
 321
 322         leondebug_irq_disable = 0;
 323         leon_debug_irqout = 0;
 324         master_l10_counter = (u32 __iomem *)&dummy_master_l10_counter;
 325         dummy_master_l10_counter = 0;
 326
 327         rootnp = of_find_node_by_path("/ambapp0");
 328         if (!rootnp)
 329                 goto bad;
 330
 331         /* Find System ID: GRLIB build ID and optional CHIP ID */
 332         pp = of_find_property(rootnp, "systemid", &len);
 333         if (pp)
 334                 amba_system_id = *(unsigned long *)pp->value;
 335
 336         /* Find IRQMP IRQ Controller Registers base adr otherwise bail out */
 337         np = of_find_node_by_name(rootnp, "GAISLER_IRQMP");
 338         if (!np) {
 339                 np = of_find_node_by_name(rootnp, "01_00d");
 340                 if (!np)
 341                         goto bad;
 342         }
 343         pp = of_find_property(np, "reg", &len);
 344         if (!pp)
 345                 goto bad;
 346         leon3_irqctrl_regs = *(struct leon3_irqctrl_regs_map **)pp->value;
 347
 348         /* Find GPTIMER Timer Registers base address otherwise bail out. */
 349         nnp = rootnp;
 350
 351 retry:
 352         np = of_find_node_by_name(nnp, "GAISLER_GPTIMER");
 353         if (!np) {
 354                 np = of_find_node_by_name(nnp, "01_011");
 355                 if (!np)
 356                         goto bad;
 357         }
 358
 359         ampopts = 0;
 360         pp = of_find_property(np, "ampopts", &len);
 361         if (pp) {
 362                 ampopts = *(int *)pp->value;
 363                 if (ampopts == 0) {
 364                         /* Skip this instance, resource already
 365                          * allocated by other OS */
 366                         nnp = np;
 367                         goto retry;
 368                 }
 369         }
 370
 371         /* Select Timer-Instance on Timer Core. Default is zero */
 372         leon3_gptimer_idx = ampopts & 0x7;
 373
 374         pp = of_find_property(np, "reg", &len);
 375         if (pp)
 376                 leon3_gptimer_regs = *(struct leon3_gptimer_regs_map **)
 377                                         pp->value;
 378         pp = of_find_property(np, "interrupts", &len);
 379         if (pp)
 380                 leon3_gptimer_irq = *(unsigned int *)pp->value;
 381
 382         if (!(leon3_gptimer_regs && leon3_irqctrl_regs && leon3_gptimer_irq))
 383                 goto bad;
 384
 385         ctrl = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl);
 386         LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl,
 387                               ctrl | LEON3_GPTIMER_CTRL_PENDING);
 388         ctrl = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl);
 389
 390         if ((ctrl & LEON3_GPTIMER_CTRL_PENDING) != 0)
 391                 leon3_gptimer_ackmask = ~LEON3_GPTIMER_CTRL_PENDING;
 392         else
 393                 leon3_gptimer_ackmask = ~0;
 394
 395         LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].val, 0);
 396         LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].rld,
 397                                 (((1000000 / HZ) - 1)));
 398         LEON3_BYPASS_STORE_PA(
 399                         &leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl, 0);
 400
 401         /*
 402          * The IRQ controller may (if implemented) consist of multiple
 403          * IRQ controllers, each mapped on a 4Kb boundary.
 404          * Each CPU may be routed to different IRQCTRLs, however
 405          * we assume that all CPUs (in SMP system) is routed to the
 406          * same IRQ Controller, and for non-SMP only one IRQCTRL is
 407          * accessed anyway.
 408          * In AMP systems, Linux must run on CPU0 for the time being.
 409          */
 410         icsel = LEON3_BYPASS_LOAD_PA(&leon3_irqctrl_regs->icsel[boot_cpu_id/8]);
 411         icsel = (icsel >> ((7 - (boot_cpu_id&0x7)) * 4)) & 0xf;
 412         leon3_irqctrl_regs += icsel;
 413
 414         /* Mask all IRQs on boot-cpu IRQ controller */
 415         LEON3_BYPASS_STORE_PA(&leon3_irqctrl_regs->mask[boot_cpu_id], 0);
 416
 417         /* Probe extended IRQ controller */
 418         eirq = (LEON3_BYPASS_LOAD_PA(&leon3_irqctrl_regs->mpstatus)
 419                 >> 16) & 0xf;
 420         if (eirq != 0)
 421                 leon_eirq_setup(eirq);
 422
 423 #ifdef CONFIG_SMP
 424         {
 425                 unsigned long flags;
 426
 427                 /*
 428                  * In SMP, sun4m adds a IPI handler to IRQ trap handler that
 429                  * LEON never must take, sun4d and LEON overwrites the branch
 430                  * with a NOP.
 431                  */
 432                 local_irq_save(flags);
 433                 patchme_maybe_smp_msg[0] = 0x01000000; /* NOP out the branch */
 434                 local_ops->cache_all();
 435                 local_irq_restore(flags);
 436         }
 437 #endif
 438
 439         config = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->config);
 440         if (config & (1 << LEON3_GPTIMER_SEPIRQ))
 441                 leon3_gptimer_irq += leon3_gptimer_idx;
 442         else if ((config & LEON3_GPTIMER_TIMERS) > 1)
 443                 pr_warn("GPTIMER uses shared irqs, using other timers of the same core will fail.\n");
 444
 445 #ifdef CONFIG_SMP
 446         /* Install per-cpu IRQ handler for broadcasted ticker */
 447         irq = leon_build_device_irq(leon3_gptimer_irq, handle_percpu_irq,
 448                                     "per-cpu", 0);
 449         err = request_irq(irq, leon_percpu_timer_ce_interrupt,
 450                           IRQF_PERCPU | IRQF_TIMER, "timer", NULL);
 451 #else
 452         irq = _leon_build_device_irq(NULL, leon3_gptimer_irq);
 453         err = request_irq(irq, timer_interrupt, IRQF_TIMER, "timer", NULL);
 454 #endif
 455         if (err) {
 456                 pr_err("Unable to attach timer IRQ%d\n", irq);
 457                 prom_halt();
 458         }
 459         LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl,
 460                               LEON3_GPTIMER_EN |
 461                               LEON3_GPTIMER_RL |
 462                               LEON3_GPTIMER_LD |
 463                               LEON3_GPTIMER_IRQEN);
 464         return;
 465 bad:
 466         printk(KERN_ERR "No Timer/irqctrl found\n");
 467         BUG();
 468         return;
 469 }
 470
 471 static void leon_clear_clock_irq(void)
 472 {
 473         u32 ctrl;
 474
 475         ctrl = LEON3_BYPASS_LOAD_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl);
 476         LEON3_BYPASS_STORE_PA(&leon3_gptimer_regs->e[leon3_gptimer_idx].ctrl,
 477                               ctrl & leon3_gptimer_ackmask);
 478 }
 479
 480 static void leon_load_profile_irq(int cpu, unsigned int limit)
 481 {
 482 }
 483
 484 #ifdef CONFIG_SMP
 485 void leon_clear_profile_irq(int cpu)
 486 {
 487 }
 488
 489 void leon_enable_irq_cpu(unsigned int irq_nr, unsigned int cpu)
 490 {
 491         unsigned long mask, flags, *addr;
 492         mask = leon_get_irqmask(irq_nr);
 493         spin_lock_irqsave(&leon_irq_lock, flags);
 494         addr = (unsigned long *)LEON_IMASK(cpu);
 495         LEON3_BYPASS_STORE_PA(addr, (LEON3_BYPASS_LOAD_PA(addr) | mask));
 496         spin_unlock_irqrestore(&leon_irq_lock, flags);
 497 }
 498
 499 #endif
 500
 501 void __init leon_init_IRQ(void)
 502 {
 503         sparc_config.init_timers      = leon_init_timers;
 504         sparc_config.build_device_irq = _leon_build_device_irq;
 505         sparc_config.clock_rate       = 1000000;
 506         sparc_config.clear_clock_irq  = leon_clear_clock_irq;
 507         sparc_config.load_profile_irq = leon_load_profile_irq;
 508 }