arch/m68k/mac/baboon.c

   1 /*
   2  * Baboon Custom IC Management
   3  *
   4  * The Baboon custom IC controls the IDE, PCMCIA and media bay on the
   5  * PowerBook 190. It multiplexes multiple interrupt sources onto the
   6  * Nubus slot $C interrupt.
   7  */
   8
   9 #include <linux/types.h>
  10 #include <linux/kernel.h>
  11 #include <linux/irq.h>
  12
  13 #include <asm/macintosh.h>
  14 #include <asm/macints.h>
  15 #include <asm/mac_baboon.h>
  16
  17 /* #define DEBUG_IRQS */
  18
  19 int baboon_present;
  20 static volatile struct baboon *baboon;
  21
  22 #if 0
  23 extern int macide_ack_intr(struct ata_channel *);
  24 #endif
  25
  26 /*
  27  * Baboon initialization.
  28  */
  29
  30 void __init baboon_init(void)
  31 {
  32         if (macintosh_config->ident != MAC_MODEL_PB190) {
  33                 baboon = NULL;
  34                 baboon_present = 0;
  35                 return;
  36         }
  37
  38         baboon = (struct baboon *) BABOON_BASE;
  39         baboon_present = 1;
  40
  41         printk("Baboon detected at %p\n", baboon);
  42 }
  43
  44 /*
  45  * Baboon interrupt handler. This works a lot like a VIA.
  46  */
  47
  48 static void baboon_irq(unsigned int irq, struct irq_desc *desc)
  49 {
  50         int irq_bit, irq_num;
  51         unsigned char events;
  52
  53 #ifdef DEBUG_IRQS
  54         printk("baboon_irq: mb_control %02X mb_ifr %02X mb_status %02X\n",
  55                 (uint) baboon->mb_control, (uint) baboon->mb_ifr,
  56                 (uint) baboon->mb_status);
  57 #endif
  58
  59         events = baboon->mb_ifr & 0x07;
  60         if (!events)
  61                 return;
  62
  63         irq_num = IRQ_BABOON_0;
  64         irq_bit = 1;
  65         do {
  66                 if (events & irq_bit) {
  67                         baboon->mb_ifr &= ~irq_bit;
  68                         generic_handle_irq(irq_num);
  69                 }
  70                 irq_bit <<= 1;
  71                 irq_num++;
  72         } while(events >= irq_bit);
  73 #if 0
  74         if (baboon->mb_ifr & 0x02) macide_ack_intr(NULL);
  75         /* for now we need to smash all interrupts */
  76         baboon->mb_ifr &= ~events;
  77 #endif
  78 }
  79
  80 /*
  81  * Register the Baboon interrupt dispatcher on nubus slot $C.
  82  */
  83
  84 void __init baboon_register_interrupts(void)
  85 {
  86         irq_set_chained_handler(IRQ_NUBUS_C, baboon_irq);
  87 }
  88
  89 /*
  90  * The means for masking individual Baboon interrupts remains a mystery.
  91  * However, since we only use the IDE IRQ, we can just enable/disable all
  92  * Baboon interrupts. If/when we handle more than one Baboon IRQ, we must
  93  * either figure out how to mask them individually or else implement the
  94  * same workaround that's used for NuBus slots (see nubus_disabled and
  95  * via_nubus_irq_shutdown).
  96  */
  97
  98 void baboon_irq_enable(int irq)
  99 {
 100 #ifdef DEBUG_IRQUSE
 101         printk("baboon_irq_enable(%d)\n", irq);
 102 #endif
 103
 104         mac_irq_enable(irq_get_irq_data(IRQ_NUBUS_C));
 105 }
 106
 107 void baboon_irq_disable(int irq)
 108 {
 109 #ifdef DEBUG_IRQUSE
 110         printk("baboon_irq_disable(%d)\n", irq);
 111 #endif
 112
 113         mac_irq_disable(irq_get_irq_data(IRQ_NUBUS_C));
 114 }