/* * Macintosh interrupts * * General design: * In contrary to the Amiga and Atari platforms, the Mac hardware seems to * exclusively use the autovector interrupts (the 'generic level0-level7' * interrupts with exception vectors 0x19-0x1f). The following interrupt levels * are used: * 1 - VIA1 * - slot 0: one second interrupt (CA2) * - slot 1: VBlank (CA1) * - slot 2: ADB data ready (SR full) * - slot 3: ADB data (CB2) * - slot 4: ADB clock (CB1) * - slot 5: timer 2 * - slot 6: timer 1 * - slot 7: status of IRQ; signals 'any enabled int.' * * 2 - VIA2 or RBV * - slot 0: SCSI DRQ (CA2) * - slot 1: NUBUS IRQ (CA1) need to read port A to find which * - slot 2: /EXP IRQ (only on IIci) * - slot 3: SCSI IRQ (CB2) * - slot 4: ASC IRQ (CB1) * - slot 5: timer 2 (not on IIci) * - slot 6: timer 1 (not on IIci) * - slot 7: status of IRQ; signals 'any enabled int.' * * 2 - OSS (IIfx only?) * - slot 0: SCSI interrupt * - slot 1: Sound interrupt * * Levels 3-6 vary by machine type. For VIA or RBV Macintoshes: * * 3 - unused (?) * * 4 - SCC (slot number determined by reading RR3 on the SSC itself) * - slot 1: SCC channel A * - slot 2: SCC channel B * * 5 - unused (?) * [serial errors or special conditions seem to raise level 6 * interrupts on some models (LC4xx?)] * * 6 - off switch (?) * * For OSS Macintoshes (IIfx only at this point): * * 3 - Nubus interrupt * - slot 0: Slot $9 * - slot 1: Slot $A * - slot 2: Slot $B * - slot 3: Slot $C * - slot 4: Slot $D * - slot 5: Slot $E * * 4 - SCC IOP * - slot 1: SCC channel A * - slot 2: SCC channel B * * 5 - ISM IOP (ADB?) * * 6 - unused * * For PSC Macintoshes (660AV, 840AV): * * 3 - PSC level 3 * - slot 0: MACE * * 4 - PSC level 4 * - slot 1: SCC channel A interrupt * - slot 2: SCC channel B interrupt * - slot 3: MACE DMA * * 5 - PSC level 5 * * 6 - PSC level 6 * * Finally we have good 'ole level 7, the non-maskable interrupt: * * 7 - NMI (programmer's switch on the back of some Macs) * Also RAM parity error on models which support it (IIc, IIfx?) * * The current interrupt logic looks something like this: * * - We install dispatchers for the autovector interrupts (1-7). These * dispatchers are responsible for querying the hardware (the * VIA/RBV/OSS/PSC chips) to determine the actual interrupt source. Using * this information a machspec interrupt number is generated by placing the * index of the interrupt hardware into the low three bits and the original * autovector interrupt number in the upper 5 bits. The handlers for the * resulting machspec interrupt are then called. * * - Nubus is a special case because its interrupts are hidden behind two * layers of hardware. Nubus interrupts come in as index 1 on VIA #2, * which translates to IRQ number 17. In this spot we install _another_ * dispatcher. This dispatcher finds the interrupting slot number (9-F) and * then forms a new machspec interrupt number as above with the slot number * minus 9 in the low three bits and the pseudo-level 7 in the upper five * bits. The handlers for this new machspec interrupt number are then * called. This puts Nubus interrupts into the range 56-62. * * - The Baboon interrupts (used on some PowerBooks) are an even more special * case. They're hidden behind the Nubus slot $C interrupt thus adding a * third layer of indirection. Why oh why did the Apple engineers do that? * * - We support "fast" and "slow" handlers, just like the Amiga port. The * fast handlers are called first and with all interrupts disabled. They * are expected to execute quickly (hence the name). The slow handlers are * called last with interrupts enabled and the interrupt level restored. * They must therefore be reentrant. * * TODO: * */ #include #include #include #include #include /* for intr_count */ #include #include #include #include #include #include #include #include #include #include #include #include #include #define DEBUG_SPURIOUS #define SHUTUP_SONIC /* * The mac_irq_list array is an array of linked lists of irq_node_t nodes. * Each node contains one handler to be called whenever the interrupt * occurs, with fast handlers listed before slow handlers. */ irq_node_t *mac_irq_list[NUM_MAC_SOURCES]; /* SCC interrupt mask */ static int scc_mask; /* * VIA/RBV hooks */ extern void via_init(void); extern void via_register_interrupts(void); extern void via_irq_enable(int); extern void via_irq_disable(int); extern void via_irq_clear(int); extern int via_irq_pending(int); /* * OSS hooks */ extern int oss_present; extern void oss_init(void); extern void oss_register_interrupts(void); extern void oss_irq_enable(int); extern void oss_irq_disable(int); extern void oss_irq_clear(int); extern int oss_irq_pending(int); /* * PSC hooks */ extern int psc_present; extern void psc_init(void); extern void psc_register_interrupts(void); extern void psc_irq_enable(int); extern void psc_irq_disable(int); extern void psc_irq_clear(int); extern int psc_irq_pending(int); /* * IOP hooks */ extern void iop_register_interrupts(void); /* * Baboon hooks */ extern int baboon_present; extern void baboon_init(void); extern void baboon_register_interrupts(void); extern void baboon_irq_enable(int); extern void baboon_irq_disable(int); extern void baboon_irq_clear(int); extern int baboon_irq_pending(int); /* * SCC interrupt routines */ static void scc_irq_enable(int); static void scc_irq_disable(int); /* * console_loglevel determines NMI handler function */ irqreturn_t mac_nmi_handler(int, void *, struct pt_regs *); irqreturn_t mac_debug_handler(int, void *, struct pt_regs *); /* #define DEBUG_MACINTS */ void mac_init_IRQ(void) { int i; #ifdef DEBUG_MACINTS printk("mac_init_IRQ(): Setting things up...\n"); #endif /* Initialize the IRQ handler lists. Initially each list is empty, */ for (i = 0; i < NUM_MAC_SOURCES; i++) { mac_irq_list[i] = NULL; } scc_mask = 0; /* Make sure the SONIC interrupt is cleared or things get ugly */ #ifdef SHUTUP_SONIC printk("Killing onboard sonic... "); /* This address should hopefully be mapped already */ if (hwreg_present((void*)(0x50f0a000))) { *(long *)(0x50f0a014) = 0x7fffL; *(long *)(0x50f0a010) = 0L; } printk("Done.\n"); #endif /* SHUTUP_SONIC */ /* * Now register the handlers for the master IRQ handlers * at levels 1-7. Most of the work is done elsewhere. */ if (oss_present) { oss_register_interrupts(); } else { via_register_interrupts(); } if (psc_present) psc_register_interrupts(); if (baboon_present) baboon_register_interrupts(); iop_register_interrupts(); cpu_request_irq(7, mac_nmi_handler, IRQ_FLG_LOCK, "NMI", mac_nmi_handler); #ifdef DEBUG_MACINTS printk("mac_init_IRQ(): Done!\n"); #endif } /* * Routines to work with irq_node_t's on linked lists lifted from * the Amiga code written by Roman Zippel. */ static inline void mac_insert_irq(irq_node_t **list, irq_node_t *node) { unsigned long flags; irq_node_t *cur; if (!node->dev_id) printk("%s: Warning: dev_id of %s is zero\n", __FUNCTION__, node->devname); local_irq_save(flags); cur = *list; if (node->flags & IRQ_FLG_FAST) { node->flags &= ~IRQ_FLG_SLOW; while (cur && cur->flags & IRQ_FLG_FAST) { list = &cur->next; cur = cur->next; } } else if (node->flags & IRQ_FLG_SLOW) { while (cur) { list = &cur->next; cur = cur->next; } } else { while (cur && !(cur->flags & IRQ_FLG_SLOW)) { list = &cur->next; cur = cur->next; } } node->next = cur; *list = node; local_irq_restore(flags); } static inline void mac_delete_irq(irq_node_t **list, void *dev_id) { unsigned long flags; irq_node_t *node; local_irq_save(flags); for (node = *list; node; list = &node->next, node = *list) { if (node->dev_id == dev_id) { *list = node->next; /* Mark it as free. */ node->handler = NULL; local_irq_restore(flags); return; } } local_irq_restore(flags); printk ("%s: tried to remove invalid irq\n", __FUNCTION__); } /* * Call all the handlers for a given interrupt. Fast handlers are called * first followed by slow handlers. * * This code taken from the original Amiga code written by Roman Zippel. */ void mac_do_irq_list(int irq, struct pt_regs *fp) { irq_node_t *node, *slow_nodes; unsigned long flags; kstat_cpu(0).irqs[irq]++; #ifdef DEBUG_SPURIOUS if (!mac_irq_list[irq] && (console_loglevel > 7)) { printk("mac_do_irq_list: spurious interrupt %d!\n", irq); return; } #endif /* serve first fast and normal handlers */ for (node = mac_irq_list[irq]; node && (!(node->flags & IRQ_FLG_SLOW)); node = node->next) node->handler(irq, node->dev_id, fp); if (!node) return; local_save_flags(flags); local_irq_restore((flags & ~0x0700) | (fp->sr & 0x0700)); /* if slow handlers exists, serve them now */ slow_nodes = node; for (; node; node = node->next) { node->handler(irq, node->dev_id, fp); } } /* * mac_enable_irq - enable an interrupt source * mac_disable_irq - disable an interrupt source * mac_clear_irq - clears a pending interrupt * mac_pending_irq - Returns the pending status of an IRQ (nonzero = pending) * * These routines are just dispatchers to the VIA/OSS/PSC routines. */ void mac_enable_irq (unsigned int irq) { int irq_src = IRQ_SRC(irq); switch(irq_src) { case 1: via_irq_enable(irq); break; case 2: case 7: if (oss_present) { oss_irq_enable(irq); } else { via_irq_enable(irq); } break; case 3: case 4: case 5: case 6: if (psc_present) { psc_irq_enable(irq); } else if (oss_present) { oss_irq_enable(irq); } else if (irq_src == 4) { scc_irq_enable(irq); } break; case 8: if (baboon_present) { baboon_irq_enable(irq); } break; } } void mac_disable_irq (unsigned int irq) { int irq_src = IRQ_SRC(irq); switch(irq_src) { case 1: via_irq_disable(irq); break; case 2: case 7: if (oss_present) { oss_irq_disable(irq); } else { via_irq_disable(irq); } break; case 3: case 4: case 5: case 6: if (psc_present) { psc_irq_disable(irq); } else if (oss_present) { oss_irq_disable(irq); } else if (irq_src == 4) { scc_irq_disable(irq); } break; case 8: if (baboon_present) { baboon_irq_disable(irq); } break; } } void mac_clear_irq( unsigned int irq ) { switch(IRQ_SRC(irq)) { case 1: via_irq_clear(irq); break; case 2: case 7: if (oss_present) { oss_irq_clear(irq); } else { via_irq_clear(irq); } break; case 3: case 4: case 5: case 6: if (psc_present) { psc_irq_clear(irq); } else if (oss_present) { oss_irq_clear(irq); } break; case 8: if (baboon_present) { baboon_irq_clear(irq); } break; } } int mac_irq_pending( unsigned int irq ) { switch(IRQ_SRC(irq)) { case 1: return via_irq_pending(irq); case 2: case 7: if (oss_present) { return oss_irq_pending(irq); } else { return via_irq_pending(irq); } case 3: case 4: case 5: case 6: if (psc_present) { return psc_irq_pending(irq); } else if (oss_present) { return oss_irq_pending(irq); } } return 0; } /* * Add an interrupt service routine to an interrupt source. * Returns 0 on success. * * FIXME: You can register interrupts on nonexistent source (ie PSC4 on a * non-PSC machine). We should return -EINVAL in those cases. */ int mac_request_irq(unsigned int irq, irqreturn_t (*handler)(int, void *, struct pt_regs *), unsigned long flags, const char *devname, void *dev_id) { irq_node_t *node; #ifdef DEBUG_MACINTS printk ("%s: irq %d requested for %s\n", __FUNCTION__, irq, devname); #endif if (irq < VIA1_SOURCE_BASE) { return cpu_request_irq(irq, handler, flags, devname, dev_id); } if (irq >= NUM_MAC_SOURCES) { printk ("%s: unknown irq %d requested by %s\n", __FUNCTION__, irq, devname); } /* Get a node and stick it onto the right list */ if (!(node = new_irq_node())) return -ENOMEM; node->handler = handler; node->flags = flags; node->dev_id = dev_id; node->devname = devname; node->next = NULL; mac_insert_irq(&mac_irq_list[irq], node); /* Now enable the IRQ source */ mac_enable_irq(irq); return 0; } /* * Removes an interrupt service routine from an interrupt source. */ void mac_free_irq(unsigned int irq, void *dev_id) { #ifdef DEBUG_MACINTS printk ("%s: irq %d freed by %p\n", __FUNCTION__, irq, dev_id); #endif if (irq < VIA1_SOURCE_BASE) { cpu_free_irq(irq, dev_id); return; } if (irq >= NUM_MAC_SOURCES) { printk ("%s: unknown irq %d freed\n", __FUNCTION__, irq); return; } mac_delete_irq(&mac_irq_list[irq], dev_id); /* If the list for this interrupt is */ /* empty then disable the source. */ if (!mac_irq_list[irq]) { mac_disable_irq(irq); } } /* * Generate a pretty listing for /proc/interrupts * * By the time we're called the autovector interrupt list has already been * generated, so we just need to do the machspec interrupts. * * 990506 (jmt) - rewritten to handle chained machspec interrupt handlers. * Also removed display of num_spurious it is already * displayed for us as autovector irq 0. */ int show_mac_interrupts(struct seq_file *p, void *v) { int i; irq_node_t *node; char *base; /* Don't do Nubus interrupts in this loop; we do them separately */ /* below so that we can print slot numbers instead of IRQ numbers */ for (i = VIA1_SOURCE_BASE ; i < NUM_MAC_SOURCES ; ++i) { /* Nonexistant interrupt or nothing registered; skip it. */ if ((node = mac_irq_list[i]) == NULL) continue; if (node->flags & IRQ_FLG_STD) continue; base = ""; switch(IRQ_SRC(i)) { case 1: base = "via1"; break; case 2: if (oss_present) { base = "oss"; } else { base = "via2"; } break; case 3: case 4: case 5: case 6: if (psc_present) { base = "psc"; } else if (oss_present) { base = "oss"; } else { if (IRQ_SRC(i) == 4) base = "scc"; } break; case 7: base = "nbus"; break; case 8: base = "bbn"; break; } seq_printf(p, "%4s %2d: %10u ", base, i, kstat_cpu(0).irqs[i]); do { if (node->flags & IRQ_FLG_FAST) { seq_puts(p, "F "); } else if (node->flags & IRQ_FLG_SLOW) { seq_puts(p, "S "); } else { seq_puts(p, " "); } seq_printf(p, "%s\n", node->devname); if ((node = node->next)) { seq_puts(p, " "); } } while(node); } return 0; } static int num_debug[8]; irqreturn_t mac_debug_handler(int irq, void *dev_id, struct pt_regs *regs) { if (num_debug[irq] < 10) { printk("DEBUG: Unexpected IRQ %d\n", irq); num_debug[irq]++; } return IRQ_HANDLED; } static int in_nmi; static volatile int nmi_hold; irqreturn_t mac_nmi_handler(int irq, void *dev_id, struct pt_regs *fp) { int i; /* * generate debug output on NMI switch if 'debug' kernel option given * (only works with Penguin!) */ in_nmi++; for (i=0; i<100; i++) udelay(1000); if (in_nmi == 1) { nmi_hold = 1; printk("... pausing, press NMI to resume ..."); } else { printk(" ok!\n"); nmi_hold = 0; } barrier(); while (nmi_hold == 1) udelay(1000); if ( console_loglevel >= 8 ) { #if 0 show_state(); printk("PC: %08lx\nSR: %04x SP: %p\n", fp->pc, fp->sr, fp); printk("d0: %08lx d1: %08lx d2: %08lx d3: %08lx\n", fp->d0, fp->d1, fp->d2, fp->d3); printk("d4: %08lx d5: %08lx a0: %08lx a1: %08lx\n", fp->d4, fp->d5, fp->a0, fp->a1); if (STACK_MAGIC != *(unsigned long *)current->kernel_stack_page) printk("Corrupted stack page\n"); printk("Process %s (pid: %d, stackpage=%08lx)\n", current->comm, current->pid, current->kernel_stack_page); if (intr_count == 1) dump_stack((struct frame *)fp); #else /* printk("NMI "); */ #endif } in_nmi--; return IRQ_HANDLED; } /* * Simple routines for masking and unmasking * SCC interrupts in cases where this can't be * done in hardware (only the PSC can do that.) */ static void scc_irq_enable(int irq) { int irq_idx = IRQ_IDX(irq); scc_mask |= (1 << irq_idx); } static void scc_irq_disable(int irq) { int irq_idx = IRQ_IDX(irq); scc_mask &= ~(1 << irq_idx); } /* * SCC master interrupt handler. We have to do a bit of magic here * to figure out what channel gave us the interrupt; putting this * here is cleaner than hacking it into drivers/char/macserial.c. */ void mac_scc_dispatch(int irq, void *dev_id, struct pt_regs *regs) { volatile unsigned char *scc = (unsigned char *) mac_bi_data.sccbase + 2; unsigned char reg; unsigned long flags; /* Read RR3 from the chip. Always do this on channel A */ /* This must be an atomic operation so disable irqs. */ local_irq_save(flags); *scc = 3; reg = *scc; local_irq_restore(flags); /* Now dispatch. Bits 0-2 are for channel B and */ /* bits 3-5 are for channel A. We can safely */ /* ignore the remaining bits here. */ /* */ /* Note that we're ignoring scc_mask for now. */ /* If we actually mask the ints then we tend to */ /* get hammered by very persistent SCC irqs, */ /* and since they're autovector interrupts they */ /* pretty much kill the system. */ if (reg & 0x38) mac_do_irq_list(IRQ_SCCA, regs); if (reg & 0x07) mac_do_irq_list(IRQ_SCCB, regs); }