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: 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: IRQ_NUBUS_C, handle: 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: IRQ_NUBUS_C)); |
85 | } |
86 | |
87 | void baboon_irq_disable(int irq) |
88 | { |
89 | mac_irq_disable(irq_get_irq_data(irq: IRQ_NUBUS_C)); |
90 | } |
91 | |