xref: /openbmc/linux/arch/m68k/mac/baboon.c (revision 7dd65feb)
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 }
143