arch/m68knommu/platform/68328/ints.c

   1 /*
   2  * linux/arch/m68knommu/platform/68328/ints.c
   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  * Copyright 1996 Roman Zippel
   9  * Copyright 1999 D. Jeff Dionne <jeff@rt-control.com>
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/types.h>
  14 #include <linux/kernel.h>
  15 #include <linux/sched.h>
  16 #include <linux/kernel_stat.h>
  17 #include <linux/errno.h>
  18
  19 #include <asm/system.h>
  20 #include <asm/irq.h>
  21 #include <asm/irqnode.h>
  22 #include <asm/traps.h>
  23 #include <asm/io.h>
  24 #include <asm/machdep.h>
  25 #include <asm/setup.h>
  26
  27 #if defined(CONFIG_M68328)
  28 #include <asm/MC68328.h>
  29 #elif defined(CONFIG_M68EZ328)
  30 #include <asm/MC68EZ328.h>
  31 #elif defined(CONFIG_M68VZ328)
  32 #include <asm/MC68VZ328.h>
  33 #endif
  34
  35 /* assembler routines */
  36 asmlinkage void system_call(void);
  37 asmlinkage void buserr(void);
  38 asmlinkage void trap(void);
  39 asmlinkage void trap3(void);
  40 asmlinkage void trap4(void);
  41 asmlinkage void trap5(void);
  42 asmlinkage void trap6(void);
  43 asmlinkage void trap7(void);
  44 asmlinkage void trap8(void);
  45 asmlinkage void trap9(void);
  46 asmlinkage void trap10(void);
  47 asmlinkage void trap11(void);
  48 asmlinkage void trap12(void);
  49 asmlinkage void trap13(void);
  50 asmlinkage void trap14(void);
  51 asmlinkage void trap15(void);
  52 asmlinkage void trap33(void);
  53 asmlinkage void trap34(void);
  54 asmlinkage void trap35(void);
  55 asmlinkage void trap36(void);
  56 asmlinkage void trap37(void);
  57 asmlinkage void trap38(void);
  58 asmlinkage void trap39(void);
  59 asmlinkage void trap40(void);
  60 asmlinkage void trap41(void);
  61 asmlinkage void trap42(void);
  62 asmlinkage void trap43(void);
  63 asmlinkage void trap44(void);
  64 asmlinkage void trap45(void);
  65 asmlinkage void trap46(void);
  66 asmlinkage void trap47(void);
  67 asmlinkage irqreturn_t bad_interrupt(int, void *, struct pt_regs *);
  68 asmlinkage irqreturn_t inthandler(void);
  69 asmlinkage irqreturn_t inthandler1(void);
  70 asmlinkage irqreturn_t inthandler2(void);
  71 asmlinkage irqreturn_t inthandler3(void);
  72 asmlinkage irqreturn_t inthandler4(void);
  73 asmlinkage irqreturn_t inthandler5(void);
  74 asmlinkage irqreturn_t inthandler6(void);
  75 asmlinkage irqreturn_t inthandler7(void);
  76
  77 extern e_vector *_ramvec;
  78
  79 /* The number of spurious interrupts */
  80 volatile unsigned int num_spurious;
  81 unsigned int local_irq_count[NR_CPUS];
  82
  83 /* irq node variables for the 32 (potential) on chip sources */
  84 static irq_node_t int_irq_list[NR_IRQS];
  85
  86 /*
  87  * This function should be called during kernel startup to initialize
  88  * the IRQ handling routines.
  89  */
  90 void init_IRQ(void)
  91 {
  92         int i;
  93
  94         /* set up the vectors */
  95         for (i = 72; i < 256; ++i)
  96                 _ramvec[i] = (e_vector) bad_interrupt;
  97
  98         _ramvec[32] = system_call;
  99
 100         _ramvec[65] = (e_vector) inthandler1;
 101         _ramvec[66] = (e_vector) inthandler2;
 102         _ramvec[67] = (e_vector) inthandler3;
 103         _ramvec[68] = (e_vector) inthandler4;
 104         _ramvec[69] = (e_vector) inthandler5;
 105         _ramvec[70] = (e_vector) inthandler6;
 106         _ramvec[71] = (e_vector) inthandler7;
 107
 108         IVR = 0x40; /* Set DragonBall IVR (interrupt base) to 64 */
 109
 110         /* initialize handlers */
 111         for (i = 0; i < NR_IRQS; i++) {
 112                 int_irq_list[i].handler = bad_interrupt;
 113                 int_irq_list[i].flags   = IRQ_FLG_STD;
 114                 int_irq_list[i].dev_id  = NULL;
 115                 int_irq_list[i].devname = NULL;
 116         }
 117
 118         /* turn off all interrupts */
 119         IMR = ~0;
 120 }
 121
 122 int request_irq(
 123         unsigned int irq,
 124         irqreturn_t (*handler)(int, void *, struct pt_regs *),
 125         unsigned long flags,
 126         const char *devname,
 127         void *dev_id)
 128 {
 129         if (irq >= NR_IRQS) {
 130                 printk (KERN_ERR "%s: Unknown IRQ %d from %s\n", __FUNCTION__, irq, devname);
 131                 return -ENXIO;
 132         }
 133
 134         if (!(int_irq_list[irq].flags & IRQ_FLG_STD)) {
 135                 if (int_irq_list[irq].flags & IRQ_FLG_LOCK) {
 136                         printk(KERN_ERR "%s: IRQ %d from %s is not replaceable\n",
 137                                __FUNCTION__, irq, int_irq_list[irq].devname);
 138                         return -EBUSY;
 139                 }
 140                 if (flags & IRQ_FLG_REPLACE) {
 141                         printk(KERN_ERR "%s: %s can't replace IRQ %d from %s\n",
 142                                __FUNCTION__, devname, irq, int_irq_list[irq].devname);
 143                         return -EBUSY;
 144                 }
 145         }
 146
 147         int_irq_list[irq].handler = handler;
 148         int_irq_list[irq].flags   = flags;
 149         int_irq_list[irq].dev_id  = dev_id;
 150         int_irq_list[irq].devname = devname;
 151
 152         IMR &= ~(1<<irq);
 153
 154         return 0;
 155 }
 156
 157 EXPORT_SYMBOL(request_irq);
 158
 159 void free_irq(unsigned int irq, void *dev_id)
 160 {
 161         if (irq >= NR_IRQS) {
 162                 printk (KERN_ERR "%s: Unknown IRQ %d\n", __FUNCTION__, irq);
 163                 return;
 164         }
 165
 166         if (int_irq_list[irq].dev_id != dev_id)
 167                 printk(KERN_INFO "%s: removing probably wrong IRQ %d from %s\n",
 168                        __FUNCTION__, irq, int_irq_list[irq].devname);
 169
 170         int_irq_list[irq].handler = bad_interrupt;
 171         int_irq_list[irq].flags   = IRQ_FLG_STD;
 172         int_irq_list[irq].dev_id  = NULL;
 173         int_irq_list[irq].devname = NULL;
 174
 175         IMR |= 1<<irq;
 176 }
 177
 178 EXPORT_SYMBOL(free_irq);
 179
 180 int show_interrupts(struct seq_file *p, void *v)
 181 {
 182         int i = *(loff_t *) v;
 183
 184         if (i < NR_IRQS) {
 185                 if (int_irq_list[i].devname) {
 186                         seq_printf(p, "%3d: %10u ", i, kstat_cpu(0).irqs[i]);
 187                         if (int_irq_list[i].flags & IRQ_FLG_LOCK)
 188                                 seq_printf(p, "L ");
 189                         else
 190                                 seq_printf(p, "  ");
 191                         seq_printf(p, "%s\n", int_irq_list[i].devname);
 192                 }
 193         }
 194         if (i == NR_IRQS)
 195                 seq_printf(p, "   : %10u   spurious\n", num_spurious);
 196
 197         return 0;
 198 }
 199
 200 /* The 68k family did not have a good way to determine the source
 201  * of interrupts until later in the family.  The EC000 core does
 202  * not provide the vector number on the stack, we vector everything
 203  * into one vector and look in the blasted mask register...
 204  * This code is designed to be fast, almost constant time, not clean!
 205  */
 206 void process_int(int vec, struct pt_regs *fp)
 207 {
 208         int irq;
 209         int mask;
 210
 211         unsigned long pend = ISR;
 212
 213         while (pend) {
 214                 if (pend & 0x0000ffff) {
 215                         if (pend & 0x000000ff) {
 216                                 if (pend & 0x0000000f) {
 217                                         mask = 0x00000001;
 218                                         irq = 0;
 219                                 } else {
 220                                         mask = 0x00000010;
 221                                         irq = 4;
 222                                 }
 223                         } else {
 224                                 if (pend & 0x00000f00) {
 225                                         mask = 0x00000100;
 226                                         irq = 8;
 227                                 } else {
 228                                         mask = 0x00001000;
 229                                         irq = 12;
 230                                 }
 231                         }
 232                 } else {
 233                         if (pend & 0x00ff0000) {
 234                                 if (pend & 0x000f0000) {
 235                                         mask = 0x00010000;
 236                                         irq = 16;
 237                                 } else {
 238                                         mask = 0x00100000;
 239                                         irq = 20;
 240                                 }
 241                         } else {
 242                                 if (pend & 0x0f000000) {
 243                                         mask = 0x01000000;
 244                                         irq = 24;
 245                                 } else {
 246                                         mask = 0x10000000;
 247                                         irq = 28;
 248                                 }
 249                         }
 250                 }
 251
 252                 while (! (mask & pend)) {
 253                         mask <<=1;
 254                         irq++;
 255                 }
 256
 257                 kstat_cpu(0).irqs[irq]++;
 258
 259                 if (int_irq_list[irq].handler) {
 260                         int_irq_list[irq].handler(irq, int_irq_list[irq].dev_id, fp);
 261                 } else {
 262                         printk(KERN_ERR "unregistered interrupt %d!\nTurning it off in the IMR...\n", irq);
 263                         IMR |= mask;
 264                 }
 265                 pend &= ~mask;
 266         }
 267 }