xref: /linux/arch/m68k/mac/baboon.c (revision 74ce1896c6c65b2f8cccbf59162d542988835835)
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 }
99