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/mm.h>
  12 #include <linux/delay.h>
  13 #include <linux/init.h>
  14
  15 #include <asm/traps.h>
  16 #include <asm/bootinfo.h>
  17 #include <asm/macintosh.h>
  18 #include <asm/macints.h>
  19 #include <asm/mac_baboon.h>
  20
  21 /* #define DEBUG_IRQS */
  22
  23 extern void mac_enable_irq(unsigned int);
  24 extern void mac_disable_irq(unsigned int);
  25
  26 int baboon_present;
  27 static volatile struct baboon *baboon;
  28 static unsigned char baboon_disabled;
  29
  30 #if 0
  31 extern int macide_ack_intr(struct ata_channel *);
  32 #endif
  33
  34 /*
  35  * Baboon initialization.
  36  */
  37
  38 void __init baboon_init(void)
  39 {
  40         if (macintosh_config->ident != MAC_MODEL_PB190) {
  41                 baboon = NULL;
  42                 baboon_present = 0;
  43                 return;
  44         }
  45
  46         baboon = (struct baboon *) BABOON_BASE;
  47         baboon_present = 1;
  48
  49         printk("Baboon detected at %p\n", baboon);
  50 }
  51
  52 /*
  53  * Baboon interrupt handler. This works a lot like a VIA.
  54  */
  55
  56 static irqreturn_t baboon_irq(int irq, void *dev_id)
  57 {
  58         int irq_bit, irq_num;
  59         unsigned char events;
  60
  61 #ifdef DEBUG_IRQS
  62         printk("baboon_irq: mb_control %02X mb_ifr %02X mb_status %02X\n",
  63                 (uint) baboon->mb_control, (uint) baboon->mb_ifr,
  64                 (uint) baboon->mb_status);
  65 #endif
  66
  67         if (!(events = baboon->mb_ifr & 0x07))
  68                 return IRQ_NONE;
  69
  70         irq_num = IRQ_BABOON_0;
  71         irq_bit = 1;
  72         do {
  73                 if (events & irq_bit) {
  74                         baboon->mb_ifr &= ~irq_bit;
  75                         m68k_handle_int(irq_num);
  76                 }
  77                 irq_bit <<= 1;
  78                 irq_num++;
  79         } while(events >= irq_bit);
  80 #if 0
  81         if (baboon->mb_ifr & 0x02) macide_ack_intr(NULL);
  82         /* for now we need to smash all interrupts */
  83         baboon->mb_ifr &= ~events;
  84 #endif
  85         return IRQ_HANDLED;
  86 }
  87
  88 /*
  89  * Register the Baboon interrupt dispatcher on nubus slot $C.
  90  */
  91
  92 void __init baboon_register_interrupts(void)
  93 {
  94         baboon_disabled = 0;
  95         if (request_irq(IRQ_NUBUS_C, baboon_irq, 0, "baboon", (void *)baboon))
  96                 pr_err("Couldn't register baboon interrupt\n");
  97 }
  98
  99 /*
 100  * The means for masking individual baboon interrupts remains a mystery, so
 101  * enable the umbrella interrupt only when no baboon interrupt is disabled.
 102  */
 103
 104 void baboon_irq_enable(int irq)
 105 {
 106         int irq_idx = IRQ_IDX(irq);
 107
 108 #ifdef DEBUG_IRQUSE
 109         printk("baboon_irq_enable(%d)\n", irq);
 110 #endif
 111
 112         baboon_disabled &= ~(1 << irq_idx);
 113         if (!baboon_disabled)
 114                 mac_enable_irq(IRQ_NUBUS_C);
 115 }
 116
 117 void baboon_irq_disable(int irq)
 118 {
 119         int irq_idx = IRQ_IDX(irq);
 120
 121 #ifdef DEBUG_IRQUSE
 122         printk("baboon_irq_disable(%d)\n", irq);
 123 #endif
 124
 125         baboon_disabled |= 1 << irq_idx;
 126         if (baboon_disabled)
 127                 mac_disable_irq(IRQ_NUBUS_C);
 128 }
 129
 130 void baboon_irq_clear(int irq)
 131 {
 132         int irq_idx = IRQ_IDX(irq);
 133
 134         baboon->mb_ifr &= ~(1 << irq_idx);
 135 }
 136
 137 int baboon_irq_pending(int irq)
 138 {
 139         int irq_idx = IRQ_IDX(irq);
 140
 141         return baboon->mb_ifr & (1 << irq_idx);
 142 }