1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Baboon Custom IC Management
4 *
5 * The Baboon custom IC controls the IDE, PCMCIA and media bay on the
6 * PowerBook 190. It multiplexes multiple interrupt sources onto the
7 * Nubus slot $C interrupt.
8 */
9
10 #include <linux/types.h>
11 #include <linux/kernel.h>
12 #include <linux/irq.h>
13
14 #include <asm/macintosh.h>
15 #include <asm/macints.h>
16 #include <asm/mac_baboon.h>
17
18 #include "mac.h"
19
20 int baboon_present;
21 static volatile struct baboon *baboon;
22
23 /*
24 * Baboon initialization.
25 */
26
27 void __init baboon_init(void)
28 {
29 if (macintosh_config->ident != MAC_MODEL_PB190) {
30 baboon = NULL;
31 baboon_present = 0;
32 return;
33 }
34
35 baboon = (struct baboon *) BABOON_BASE;
36 baboon_present = 1;
37
38 pr_debug("Baboon detected at %p\n", baboon);
39 }
40
41 /*
42 * Baboon interrupt handler.
43 * XXX how do you clear a pending IRQ? is it even necessary?
44 */
45
46 static void baboon_irq(struct irq_desc *desc)
47 {
48 short events, irq_bit;
49 int irq_num;
50
51 events = baboon->mb_ifr & 0x07;
52 irq_num = IRQ_BABOON_0;
53 irq_bit = 1;
54 do {
55 if (events & irq_bit) {
56 events &= ~irq_bit;
57 generic_handle_irq(irq_num);
58 }
59 ++irq_num;
60 irq_bit <<= 1;
61 } while (events);
62 }
63
64 /*
65 * Register the Baboon interrupt dispatcher on nubus slot $C.
66 */
67
68 void __init baboon_register_interrupts(void)
69 {
70 irq_set_chained_handler(IRQ_NUBUS_C, baboon_irq);
71 }
72
73 /*
74 * The means for masking individual Baboon interrupts remains a mystery.
75 * However, since we only use the IDE IRQ, we can just enable/disable all
76 * Baboon interrupts. If/when we handle more than one Baboon IRQ, we must
77 * either figure out how to mask them individually or else implement the
78 * same workaround that's used for NuBus slots (see nubus_disabled and
79 * via_nubus_irq_shutdown).
80 */
81
82 void baboon_irq_enable(int irq)
83 {
84 mac_irq_enable(irq_get_irq_data(IRQ_NUBUS_C));
85 }
86
87 void baboon_irq_disable(int irq)
88 {
89 mac_irq_disable(irq_get_irq_data(IRQ_NUBUS_C));
90 }
91
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