Linux Kernel  3.7.1
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
baboon.c
Go to the documentation of this file.
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 
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 
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 
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 
114 }