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 int baboon_present;
  18 static volatile struct baboon *baboon;
  19
  20 #if 0
  21 extern int macide_ack_intr(struct ata_channel *);
  22 #endif
  23
  24 /*
  25  * Baboon initialization.
  26  */
  27
  28 void __init baboon_init(void)
  29 {
  30         if (macintosh_config->ident != MAC_MODEL_PB190) {
  31                 baboon = NULL;
  32                 baboon_present = 0;
  33                 return;
  34         }
  35
  36         baboon = (struct baboon *) BABOON_BASE;
  37         baboon_present = 1;
  38
  39         printk("Baboon detected at %p\n", baboon);
  40 }
  41
  42 /*
  43  * Baboon interrupt handler. This works a lot like a VIA.
  44  */
  45
  46 static void baboon_irq(struct irq_desc *desc)
  47 {
  48         int irq_bit, irq_num;
  49         unsigned char events;
  50
  51         events = baboon->mb_ifr & 0x07;
  52         if (!events)
  53                 return;
  54
  55         irq_num = IRQ_BABOON_0;
  56         irq_bit = 1;
  57         do {
  58                 if (events & irq_bit) {
  59                         baboon->mb_ifr &= ~irq_bit;
  60                         generic_handle_irq(irq_num);
  61                 }
  62                 irq_bit <<= 1;
  63                 irq_num++;
  64         } while(events >= irq_bit);
  65 #if 0
  66         if (baboon->mb_ifr & 0x02) macide_ack_intr(NULL);
  67         /* for now we need to smash all interrupts */
  68         baboon->mb_ifr &= ~events;
  69 #endif
  70 }
  71
  72 /*
  73  * Register the Baboon interrupt dispatcher on nubus slot $C.
  74  */
  75
  76 void __init baboon_register_interrupts(void)
  77 {
  78         irq_set_chained_handler(IRQ_NUBUS_C, baboon_irq);
  79 }
  80
  81 /*
  82  * The means for masking individual Baboon interrupts remains a mystery.
  83  * However, since we only use the IDE IRQ, we can just enable/disable all
  84  * Baboon interrupts. If/when we handle more than one Baboon IRQ, we must
  85  * either figure out how to mask them individually or else implement the
  86  * same workaround that's used for NuBus slots (see nubus_disabled and
  87  * via_nubus_irq_shutdown).
  88  */
  89
  90 void baboon_irq_enable(int irq)
  91 {
  92         mac_irq_enable(irq_get_irq_data(IRQ_NUBUS_C));
  93 }
  94
  95 void baboon_irq_disable(int irq)
  96 {
  97         mac_irq_disable(irq_get_irq_data(IRQ_NUBUS_C));
  98 }