linux/arch/m68k/kernel/ints.c
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   1/*
   2 * linux/arch/m68k/kernel/ints.c -- Linux/m68k general interrupt handling code
   3 *
   4 * This file is subject to the terms and conditions of the GNU General Public
   5 * License.  See the file COPYING in the main directory of this archive
   6 * for more details.
   7 *
   8 * 07/03/96: Timer initialization, and thus mach_sched_init(),
   9 *           removed from request_irq() and moved to init_time().
  10 *           We should therefore consider renaming our add_isr() and
  11 *           remove_isr() to request_irq() and free_irq()
  12 *           respectively, so they are compliant with the other
  13 *           architectures.                                     /Jes
  14 * 11/07/96: Changed all add_/remove_isr() to request_/free_irq() calls.
  15 *           Removed irq list support, if any machine needs an irq server
  16 *           it must implement this itself (as it's already done), instead
  17 *           only default handler are used with mach_default_handler.
  18 *           request_irq got some flags different from other architectures:
  19 *           - IRQ_FLG_REPLACE : Replace an existing handler (the default one
  20 *                               can be replaced without this flag)
  21 *           - IRQ_FLG_LOCK : handler can't be replaced
  22 *           There are other machine depending flags, see there
  23 *           If you want to replace a default handler you should know what
  24 *           you're doing, since it might handle different other irq sources
  25 *           which must be served                               /Roman Zippel
  26 */
  27
  28#include <linux/module.h>
  29#include <linux/types.h>
  30#include <linux/sched.h>
  31#include <linux/interrupt.h>
  32#include <linux/kernel_stat.h>
  33#include <linux/errno.h>
  34#include <linux/init.h>
  35
  36#include <asm/setup.h>
  37#include <asm/system.h>
  38#include <asm/irq.h>
  39#include <asm/traps.h>
  40#include <asm/page.h>
  41#include <asm/machdep.h>
  42#include <asm/cacheflush.h>
  43#include <asm/irq_regs.h>
  44
  45#ifdef CONFIG_Q40
  46#include <asm/q40ints.h>
  47#endif
  48
  49extern u32 auto_irqhandler_fixup[];
  50extern u32 user_irqhandler_fixup[];
  51extern u16 user_irqvec_fixup[];
  52
  53/* table for system interrupt handlers */
  54static struct irq_node *irq_list[NR_IRQS];
  55static struct irq_controller *irq_controller[NR_IRQS];
  56static int irq_depth[NR_IRQS];
  57
  58static int m68k_first_user_vec;
  59
  60static struct irq_controller auto_irq_controller = {
  61        .name           = "auto",
  62        .lock           = __SPIN_LOCK_UNLOCKED(auto_irq_controller.lock),
  63        .startup        = m68k_irq_startup,
  64        .shutdown       = m68k_irq_shutdown,
  65};
  66
  67static struct irq_controller user_irq_controller = {
  68        .name           = "user",
  69        .lock           = __SPIN_LOCK_UNLOCKED(user_irq_controller.lock),
  70        .startup        = m68k_irq_startup,
  71        .shutdown       = m68k_irq_shutdown,
  72};
  73
  74#define NUM_IRQ_NODES 100
  75static irq_node_t nodes[NUM_IRQ_NODES];
  76
  77/*
  78 * void init_IRQ(void)
  79 *
  80 * Parameters:  None
  81 *
  82 * Returns:     Nothing
  83 *
  84 * This function should be called during kernel startup to initialize
  85 * the IRQ handling routines.
  86 */
  87
  88void __init init_IRQ(void)
  89{
  90        int i;
  91
  92        /* assembly irq entry code relies on this... */
  93        if (HARDIRQ_MASK != 0x00ff0000) {
  94                extern void hardirq_mask_is_broken(void);
  95                hardirq_mask_is_broken();
  96        }
  97
  98        for (i = IRQ_AUTO_1; i <= IRQ_AUTO_7; i++)
  99                irq_controller[i] = &auto_irq_controller;
 100
 101        mach_init_IRQ();
 102}
 103
 104/**
 105 * m68k_setup_auto_interrupt
 106 * @handler: called from auto vector interrupts
 107 *
 108 * setup the handler to be called from auto vector interrupts instead of the
 109 * standard __m68k_handle_int(), it will be called with irq numbers in the range
 110 * from IRQ_AUTO_1 - IRQ_AUTO_7.
 111 */
 112void __init m68k_setup_auto_interrupt(void (*handler)(unsigned int, struct pt_regs *))
 113{
 114        if (handler)
 115                *auto_irqhandler_fixup = (u32)handler;
 116        flush_icache();
 117}
 118
 119/**
 120 * m68k_setup_user_interrupt
 121 * @vec: first user vector interrupt to handle
 122 * @cnt: number of active user vector interrupts
 123 * @handler: called from user vector interrupts
 124 *
 125 * setup user vector interrupts, this includes activating the specified range
 126 * of interrupts, only then these interrupts can be requested (note: this is
 127 * different from auto vector interrupts). An optional handler can be installed
 128 * to be called instead of the default __m68k_handle_int(), it will be called
 129 * with irq numbers starting from IRQ_USER.
 130 */
 131void __init m68k_setup_user_interrupt(unsigned int vec, unsigned int cnt,
 132                                      void (*handler)(unsigned int, struct pt_regs *))
 133{
 134        int i;
 135
 136        BUG_ON(IRQ_USER + cnt > NR_IRQS);
 137        m68k_first_user_vec = vec;
 138        for (i = 0; i < cnt; i++)
 139                irq_controller[IRQ_USER + i] = &user_irq_controller;
 140        *user_irqvec_fixup = vec - IRQ_USER;
 141        if (handler)
 142                *user_irqhandler_fixup = (u32)handler;
 143        flush_icache();
 144}
 145
 146/**
 147 * m68k_setup_irq_controller
 148 * @contr: irq controller which controls specified irq
 149 * @irq: first irq to be managed by the controller
 150 *
 151 * Change the controller for the specified range of irq, which will be used to
 152 * manage these irq. auto/user irq already have a default controller, which can
 153 * be changed as well, but the controller probably should use m68k_irq_startup/
 154 * m68k_irq_shutdown.
 155 */
 156void m68k_setup_irq_controller(struct irq_controller *contr, unsigned int irq,
 157                               unsigned int cnt)
 158{
 159        int i;
 160
 161        for (i = 0; i < cnt; i++)
 162                irq_controller[irq + i] = contr;
 163}
 164
 165irq_node_t *new_irq_node(void)
 166{
 167        irq_node_t *node;
 168        short i;
 169
 170        for (node = nodes, i = NUM_IRQ_NODES-1; i >= 0; node++, i--) {
 171                if (!node->handler) {
 172                        memset(node, 0, sizeof(*node));
 173                        return node;
 174                }
 175        }
 176
 177        printk ("new_irq_node: out of nodes\n");
 178        return NULL;
 179}
 180
 181int setup_irq(unsigned int irq, struct irq_node *node)
 182{
 183        struct irq_controller *contr;
 184        struct irq_node **prev;
 185        unsigned long flags;
 186
 187        if (irq >= NR_IRQS || !(contr = irq_controller[irq])) {
 188                printk("%s: Incorrect IRQ %d from %s\n",
 189                       __func__, irq, node->devname);
 190                return -ENXIO;
 191        }
 192
 193        spin_lock_irqsave(&contr->lock, flags);
 194
 195        prev = irq_list + irq;
 196        if (*prev) {
 197                /* Can't share interrupts unless both agree to */
 198                if (!((*prev)->flags & node->flags & IRQF_SHARED)) {
 199                        spin_unlock_irqrestore(&contr->lock, flags);
 200                        return -EBUSY;
 201                }
 202                while (*prev)
 203                        prev = &(*prev)->next;
 204        }
 205
 206        if (!irq_list[irq]) {
 207                if (contr->startup)
 208                        contr->startup(irq);
 209                else
 210                        contr->enable(irq);
 211        }
 212        node->next = NULL;
 213        *prev = node;
 214
 215        spin_unlock_irqrestore(&contr->lock, flags);
 216
 217        return 0;
 218}
 219
 220int request_irq(unsigned int irq,
 221                irq_handler_t handler,
 222                unsigned long flags, const char *devname, void *dev_id)
 223{
 224        struct irq_node *node;
 225        int res;
 226
 227        node = new_irq_node();
 228        if (!node)
 229                return -ENOMEM;
 230
 231        node->handler = handler;
 232        node->flags   = flags;
 233        node->dev_id  = dev_id;
 234        node->devname = devname;
 235
 236        res = setup_irq(irq, node);
 237        if (res)
 238                node->handler = NULL;
 239
 240        return res;
 241}
 242
 243EXPORT_SYMBOL(request_irq);
 244
 245void free_irq(unsigned int irq, void *dev_id)
 246{
 247        struct irq_controller *contr;
 248        struct irq_node **p, *node;
 249        unsigned long flags;
 250
 251        if (irq >= NR_IRQS || !(contr = irq_controller[irq])) {
 252                printk("%s: Incorrect IRQ %d\n", __func__, irq);
 253                return;
 254        }
 255
 256        spin_lock_irqsave(&contr->lock, flags);
 257
 258        p = irq_list + irq;
 259        while ((node = *p)) {
 260                if (node->dev_id == dev_id)
 261                        break;
 262                p = &node->next;
 263        }
 264
 265        if (node) {
 266                *p = node->next;
 267                node->handler = NULL;
 268        } else
 269                printk("%s: Removing probably wrong IRQ %d\n",
 270                       __func__, irq);
 271
 272        if (!irq_list[irq]) {
 273                if (contr->shutdown)
 274                        contr->shutdown(irq);
 275                else
 276                        contr->disable(irq);
 277        }
 278
 279        spin_unlock_irqrestore(&contr->lock, flags);
 280}
 281
 282EXPORT_SYMBOL(free_irq);
 283
 284void enable_irq(unsigned int irq)
 285{
 286        struct irq_controller *contr;
 287        unsigned long flags;
 288
 289        if (irq >= NR_IRQS || !(contr = irq_controller[irq])) {
 290                printk("%s: Incorrect IRQ %d\n",
 291                       __func__, irq);
 292                return;
 293        }
 294
 295        spin_lock_irqsave(&contr->lock, flags);
 296        if (irq_depth[irq]) {
 297                if (!--irq_depth[irq]) {
 298                        if (contr->enable)
 299                                contr->enable(irq);
 300                }
 301        } else
 302                WARN_ON(1);
 303        spin_unlock_irqrestore(&contr->lock, flags);
 304}
 305
 306EXPORT_SYMBOL(enable_irq);
 307
 308void disable_irq(unsigned int irq)
 309{
 310        struct irq_controller *contr;
 311        unsigned long flags;
 312
 313        if (irq >= NR_IRQS || !(contr = irq_controller[irq])) {
 314                printk("%s: Incorrect IRQ %d\n",
 315                       __func__, irq);
 316                return;
 317        }
 318
 319        spin_lock_irqsave(&contr->lock, flags);
 320        if (!irq_depth[irq]++) {
 321                if (contr->disable)
 322                        contr->disable(irq);
 323        }
 324        spin_unlock_irqrestore(&contr->lock, flags);
 325}
 326
 327EXPORT_SYMBOL(disable_irq);
 328
 329void disable_irq_nosync(unsigned int irq) __attribute__((alias("disable_irq")));
 330
 331EXPORT_SYMBOL(disable_irq_nosync);
 332
 333int m68k_irq_startup(unsigned int irq)
 334{
 335        if (irq <= IRQ_AUTO_7)
 336                vectors[VEC_SPUR + irq] = auto_inthandler;
 337        else
 338                vectors[m68k_first_user_vec + irq - IRQ_USER] = user_inthandler;
 339        return 0;
 340}
 341
 342void m68k_irq_shutdown(unsigned int irq)
 343{
 344        if (irq <= IRQ_AUTO_7)
 345                vectors[VEC_SPUR + irq] = bad_inthandler;
 346        else
 347                vectors[m68k_first_user_vec + irq - IRQ_USER] = bad_inthandler;
 348}
 349
 350
 351/*
 352 * Do we need these probe functions on the m68k?
 353 *
 354 *  ... may be useful with ISA devices
 355 */
 356unsigned long probe_irq_on (void)
 357{
 358#ifdef CONFIG_Q40
 359        if (MACH_IS_Q40)
 360                return q40_probe_irq_on();
 361#endif
 362        return 0;
 363}
 364
 365EXPORT_SYMBOL(probe_irq_on);
 366
 367int probe_irq_off (unsigned long irqs)
 368{
 369#ifdef CONFIG_Q40
 370        if (MACH_IS_Q40)
 371                return q40_probe_irq_off(irqs);
 372#endif
 373        return 0;
 374}
 375
 376EXPORT_SYMBOL(probe_irq_off);
 377
 378unsigned int irq_canonicalize(unsigned int irq)
 379{
 380#ifdef CONFIG_Q40
 381        if (MACH_IS_Q40 && irq == 11)
 382                irq = 10;
 383#endif
 384        return irq;
 385}
 386
 387EXPORT_SYMBOL(irq_canonicalize);
 388
 389asmlinkage void m68k_handle_int(unsigned int irq)
 390{
 391        struct irq_node *node;
 392        kstat_cpu(0).irqs[irq]++;
 393        node = irq_list[irq];
 394        do {
 395                node->handler(irq, node->dev_id);
 396                node = node->next;
 397        } while (node);
 398}
 399
 400asmlinkage void __m68k_handle_int(unsigned int irq, struct pt_regs *regs)
 401{
 402        struct pt_regs *old_regs;
 403        old_regs = set_irq_regs(regs);
 404        m68k_handle_int(irq);
 405        set_irq_regs(old_regs);
 406}
 407
 408asmlinkage void handle_badint(struct pt_regs *regs)
 409{
 410        kstat_cpu(0).irqs[0]++;
 411        printk("unexpected interrupt from %u\n", regs->vector);
 412}
 413
 414int show_interrupts(struct seq_file *p, void *v)
 415{
 416        struct irq_controller *contr;
 417        struct irq_node *node;
 418        int i = *(loff_t *) v;
 419
 420        /* autovector interrupts */
 421        if (irq_list[i]) {
 422                contr = irq_controller[i];
 423                node = irq_list[i];
 424                seq_printf(p, "%-8s %3u: %10u %s", contr->name, i, kstat_cpu(0).irqs[i], node->devname);
 425                while ((node = node->next))
 426                        seq_printf(p, ", %s", node->devname);
 427                seq_puts(p, "\n");
 428        }
 429        return 0;
 430}
 431
 432void init_irq_proc(void)
 433{
 434        /* Insert /proc/irq driver here */
 435}
 436
 437