arch/ppc/amiga/amiints.c

   1 /*
   2  * arch/ppc/amiga/amiints.c -- Amiga Linux 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  * 11/07/96: rewritten interrupt handling, irq lists are exists now only for
   9  *           this sources where it makes sense (VERTB/PORTS/EXTER) and you must
  10  *           be careful that dev_id for this sources is unique since this the
  11  *           only possibility to distinguish between different handlers for
  12  *           free_irq. irq lists also have different irq flags:
  13  *           - IRQ_FLG_FAST: handler is inserted at top of list (after other
  14  *                           fast handlers)
  15  *           - IRQ_FLG_SLOW: handler is inserted at bottom of list and before
  16  *                           they're executed irq level is set to the previous
  17  *                           one, but handlers don't need to be reentrant, if
  18  *                           reentrance occurred, slow handlers will be just
  19  *                           called again.
  20  *           The whole interrupt handling for CIAs is moved to cia.c
  21  *           /Roman Zippel
  22  *
  23  * 07/08/99: rewamp of the interrupt handling - we now have two types of
  24  *           interrupts, normal and fast handlers, fast handlers being
  25  *           marked with SA_INTERRUPT and runs with all other interrupts
  26  *           disabled. Normal interrupts disable their own source but
  27  *           run with all other interrupt sources enabled.
  28  *           PORTS and EXTER interrupts are always shared even if the
  29  *           drivers do not explicitly mark this when calling
  30  *           request_irq which they really should do.
  31  *           This is similar to the way interrupts are handled on all
  32  *           other architectures and makes a ton of sense besides
  33  *           having the advantage of making it easier to share
  34  *           drivers.
  35  *           /Jes
  36  */
  37
  38 #include <linux/config.h>
  39 #include <linux/types.h>
  40 #include <linux/kernel.h>
  41 #include <linux/sched.h>
  42 #include <linux/interrupt.h>
  43 #include <linux/irq.h>
  44 #include <linux/kernel_stat.h>
  45 #include <linux/init.h>
  46
  47 #include <asm/system.h>
  48 #include <asm/irq.h>
  49 #include <asm/traps.h>
  50 #include <asm/amigahw.h>
  51 #include <asm/amigaints.h>
  52 #include <asm/amipcmcia.h>
  53
  54 #ifdef CONFIG_APUS
  55 #include <asm/amigappc.h>
  56 #endif
  57
  58 extern void cia_init_IRQ(struct ciabase *base);
  59
  60 unsigned short ami_intena_vals[AMI_STD_IRQS] = {
  61         IF_VERTB, IF_COPER, IF_AUD0, IF_AUD1, IF_AUD2, IF_AUD3, IF_BLIT,
  62         IF_DSKSYN, IF_DSKBLK, IF_RBF, IF_TBE, IF_SOFT, IF_PORTS, IF_EXTER
  63 };
  64 static const unsigned char ami_servers[AMI_STD_IRQS] = {
  65         1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1
  66 };
  67
  68 static short ami_ablecount[AMI_IRQS];
  69
  70 static void ami_badint(int irq, void *dev_id, struct pt_regs *fp)
  71 {
  72 /*      num_spurious += 1;*/
  73 }
  74
  75 /*
  76  * void amiga_init_IRQ(void)
  77  *
  78  * Parameters:  None
  79  *
  80  * Returns:     Nothing
  81  *
  82  * This function should be called during kernel startup to initialize
  83  * the amiga IRQ handling routines.
  84  */
  85
  86 __init
  87 void amiga_init_IRQ(void)
  88 {
  89         int i;
  90
  91         for (i = 0; i < AMI_IRQS; i++)
  92                 ami_ablecount[i] = 0;
  93
  94         /* turn off PCMCIA interrupts */
  95         if (AMIGAHW_PRESENT(PCMCIA))
  96                 gayle.inten = GAYLE_IRQ_IDE;
  97
  98         /* turn off all interrupts... */
  99         custom.intena = 0x7fff;
 100         custom.intreq = 0x7fff;
 101
 102 #ifdef CONFIG_APUS
 103         /* Clear any inter-CPU interrupt requests. Circumvents bug in
 104            Blizzard IPL emulation HW (or so it appears). */
 105         APUS_WRITE(APUS_INT_LVL, INTLVL_SETRESET | INTLVL_MASK);
 106
 107         /* Init IPL emulation. */
 108         APUS_WRITE(APUS_REG_INT, REGINT_INTMASTER | REGINT_ENABLEIPL);
 109         APUS_WRITE(APUS_IPL_EMU, IPLEMU_DISABLEINT);
 110         APUS_WRITE(APUS_IPL_EMU, IPLEMU_SETRESET | IPLEMU_IPLMASK);
 111 #endif
 112         /* ... and enable the master interrupt bit */
 113         custom.intena = IF_SETCLR | IF_INTEN;
 114
 115         cia_init_IRQ(&ciaa_base);
 116         cia_init_IRQ(&ciab_base);
 117 }
 118
 119 /*
 120  * Enable/disable a particular machine specific interrupt source.
 121  * Note that this may affect other interrupts in case of a shared interrupt.
 122  * This function should only be called for a _very_ short time to change some
 123  * internal data, that may not be changed by the interrupt at the same time.
 124  * ami_(enable|disable)_irq calls may also be nested.
 125  */
 126
 127 void amiga_enable_irq(unsigned int irq)
 128 {
 129         if (irq >= AMI_IRQS) {
 130                 printk("%s: Unknown IRQ %d\n", __FUNCTION__, irq);
 131                 return;
 132         }
 133
 134         ami_ablecount[irq]--;
 135         if (ami_ablecount[irq]<0)
 136                 ami_ablecount[irq]=0;
 137         else if (ami_ablecount[irq])
 138                 return;
 139
 140         /* No action for auto-vector interrupts */
 141         if (irq >= IRQ_AMIGA_AUTO){
 142                 printk("%s: Trying to enable auto-vector IRQ %i\n",
 143                        __FUNCTION__, irq - IRQ_AMIGA_AUTO);
 144                 return;
 145         }
 146
 147         if (irq >= IRQ_AMIGA_CIAA) {
 148                 cia_set_irq(irq, 0);
 149                 cia_able_irq(irq, 1);
 150                 return;
 151         }
 152
 153         /* enable the interrupt */
 154         custom.intena = IF_SETCLR | ami_intena_vals[irq];
 155 }
 156
 157 void amiga_disable_irq(unsigned int irq)
 158 {
 159         if (irq >= AMI_IRQS) {
 160                 printk("%s: Unknown IRQ %d\n", __FUNCTION__, irq);
 161                 return;
 162         }
 163
 164         if (ami_ablecount[irq]++)
 165                 return;
 166
 167         /* No action for auto-vector interrupts */
 168         if (irq >= IRQ_AMIGA_AUTO) {
 169                 printk("%s: Trying to disable auto-vector IRQ %i\n",
 170                        __FUNCTION__, irq - IRQ_AMIGA_AUTO);
 171                 return;
 172         }
 173
 174         if (irq >= IRQ_AMIGA_CIAA) {
 175                 cia_able_irq(irq, 0);
 176                 return;
 177         }
 178
 179         /* disable the interrupt */
 180         custom.intena = ami_intena_vals[irq];
 181 }
 182
 183 inline void amiga_do_irq(int irq, struct pt_regs *fp)
 184 {
 185         irq_desc_t *desc = irq_desc + irq;
 186         struct irqaction *action = desc->action;
 187
 188         kstat_cpu(0).irqs[irq]++;
 189         action->handler(irq, action->dev_id, fp);
 190 }
 191
 192 void amiga_do_irq_list(int irq, struct pt_regs *fp)
 193 {
 194         irq_desc_t *desc = irq_desc + irq;
 195         struct irqaction *action;
 196
 197         kstat_cpu(0).irqs[irq]++;
 198
 199         custom.intreq = ami_intena_vals[irq];
 200
 201         for (action = desc->action; action; action = action->next)
 202                 action->handler(irq, action->dev_id, fp);
 203 }
 204
 205 /*
 206  * The builtin Amiga hardware interrupt handlers.
 207  */
 208
 209 static void ami_int1(int irq, void *dev_id, struct pt_regs *fp)
 210 {
 211         unsigned short ints = custom.intreqr & custom.intenar;
 212
 213         /* if serial transmit buffer empty, interrupt */
 214         if (ints & IF_TBE) {
 215                 custom.intreq = IF_TBE;
 216                 amiga_do_irq(IRQ_AMIGA_TBE, fp);
 217         }
 218
 219         /* if floppy disk transfer complete, interrupt */
 220         if (ints & IF_DSKBLK) {
 221                 custom.intreq = IF_DSKBLK;
 222                 amiga_do_irq(IRQ_AMIGA_DSKBLK, fp);
 223         }
 224
 225         /* if software interrupt set, interrupt */
 226         if (ints & IF_SOFT) {
 227                 custom.intreq = IF_SOFT;
 228                 amiga_do_irq(IRQ_AMIGA_SOFT, fp);
 229         }
 230 }
 231
 232 static void ami_int3(int irq, void *dev_id, struct pt_regs *fp)
 233 {
 234         unsigned short ints = custom.intreqr & custom.intenar;
 235
 236         /* if a blitter interrupt */
 237         if (ints & IF_BLIT) {
 238                 custom.intreq = IF_BLIT;
 239                 amiga_do_irq(IRQ_AMIGA_BLIT, fp);
 240         }
 241
 242         /* if a copper interrupt */
 243         if (ints & IF_COPER) {
 244                 custom.intreq = IF_COPER;
 245                 amiga_do_irq(IRQ_AMIGA_COPPER, fp);
 246         }
 247
 248         /* if a vertical blank interrupt */
 249         if (ints & IF_VERTB)
 250                 amiga_do_irq_list(IRQ_AMIGA_VERTB, fp);
 251 }
 252
 253 static void ami_int4(int irq, void *dev_id, struct pt_regs *fp)
 254 {
 255         unsigned short ints = custom.intreqr & custom.intenar;
 256
 257         /* if audio 0 interrupt */
 258         if (ints & IF_AUD0) {
 259                 custom.intreq = IF_AUD0;
 260                 amiga_do_irq(IRQ_AMIGA_AUD0, fp);
 261         }
 262
 263         /* if audio 1 interrupt */
 264         if (ints & IF_AUD1) {
 265                 custom.intreq = IF_AUD1;
 266                 amiga_do_irq(IRQ_AMIGA_AUD1, fp);
 267         }
 268
 269         /* if audio 2 interrupt */
 270         if (ints & IF_AUD2) {
 271                 custom.intreq = IF_AUD2;
 272                 amiga_do_irq(IRQ_AMIGA_AUD2, fp);
 273         }
 274
 275         /* if audio 3 interrupt */
 276         if (ints & IF_AUD3) {
 277                 custom.intreq = IF_AUD3;
 278                 amiga_do_irq(IRQ_AMIGA_AUD3, fp);
 279         }
 280 }
 281
 282 static void ami_int5(int irq, void *dev_id, struct pt_regs *fp)
 283 {
 284         unsigned short ints = custom.intreqr & custom.intenar;
 285
 286         /* if serial receive buffer full interrupt */
 287         if (ints & IF_RBF) {
 288                 /* acknowledge of IF_RBF must be done by the serial interrupt */
 289                 amiga_do_irq(IRQ_AMIGA_RBF, fp);
 290         }
 291
 292         /* if a disk sync interrupt */
 293         if (ints & IF_DSKSYN) {
 294                 custom.intreq = IF_DSKSYN;
 295                 amiga_do_irq(IRQ_AMIGA_DSKSYN, fp);
 296         }
 297 }
 298
 299 static void ami_int7(int irq, void *dev_id, struct pt_regs *fp)
 300 {
 301         panic ("level 7 interrupt received\n");
 302 }
 303
 304 #ifdef CONFIG_APUS
 305 /* The PPC irq handling links all handlers requested on the same vector
 306    and executes them in a loop. Having ami_badint at the end of the chain
 307    is a bad idea. */
 308 struct irqaction amiga_sys_irqaction[AUTO_IRQS] = {
 309         { .handler = ami_badint, .name = "spurious int" },
 310         { .handler = ami_int1, .name = "int1 handler" },
 311         { 0, /* CIAA */ },
 312         { .handler = ami_int3, .name = "int3 handler" },
 313         { .handler = ami_int4, .name = "int4 handler" },
 314         { .handler = ami_int5, .name = "int5 handler" },
 315         { 0, /* CIAB */ },
 316         { .handler = ami_int7, .name = "int7 handler" },
 317 };
 318 #else
 319 void (*amiga_default_handler[SYS_IRQS])(int, void *, struct pt_regs *) = {
 320         ami_badint, ami_int1, ami_badint, ami_int3,
 321         ami_int4, ami_int5, ami_badint, ami_int7
 322 };
 323 #endif