1/*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License.  See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * Copyright (C) 1992 Linus Torvalds
7 * Copyright (C) 1994 - 2001, 2003 Ralf Baechle
8 */
9#include <linux/init.h>
10#include <linux/interrupt.h>
11#include <linux/kernel.h>
12#include <linux/spinlock.h>
13
14#include <asm/i8259.h>
15#include <asm/io.h>
16#include <asm/jazz.h>
17
18static DEFINE_SPINLOCK(r4030_lock);
19
20static void enable_r4030_irq(unsigned int irq)
21{
22	unsigned int mask = 1 << (irq - JAZZ_PARALLEL_IRQ);
23	unsigned long flags;
24
25	spin_lock_irqsave(&r4030_lock, flags);
26	mask |= r4030_read_reg16(JAZZ_IO_IRQ_ENABLE);
27	r4030_write_reg16(JAZZ_IO_IRQ_ENABLE, mask);
28	spin_unlock_irqrestore(&r4030_lock, flags);
29}
30
31void disable_r4030_irq(unsigned int irq)
32{
33	unsigned int mask = ~(1 << (irq - JAZZ_PARALLEL_IRQ));
34	unsigned long flags;
35
36	spin_lock_irqsave(&r4030_lock, flags);
37	mask &= r4030_read_reg16(JAZZ_IO_IRQ_ENABLE);
38	r4030_write_reg16(JAZZ_IO_IRQ_ENABLE, mask);
39	spin_unlock_irqrestore(&r4030_lock, flags);
40}
41
42static struct irq_chip r4030_irq_type = {
43	.name = "R4030",
44	.ack = disable_r4030_irq,
45	.mask = disable_r4030_irq,
46	.mask_ack = disable_r4030_irq,
47	.unmask = enable_r4030_irq,
48};
49
50void __init init_r4030_ints(void)
51{
52	int i;
53
54	for (i = JAZZ_PARALLEL_IRQ; i <= JAZZ_TIMER_IRQ; i++)
55		set_irq_chip_and_handler(i, &r4030_irq_type, handle_level_irq);
56
57	r4030_write_reg16(JAZZ_IO_IRQ_ENABLE, 0);
58	r4030_read_reg16(JAZZ_IO_IRQ_SOURCE);		/* clear pending IRQs */
59	r4030_read_reg32(JAZZ_R4030_INVAL_ADDR);	/* clear error bits */
60}
61
62/*
63 * On systems with i8259-style interrupt controllers we assume for
64 * driver compatibility reasons interrupts 0 - 15 to be the i8259
65 * interrupts even if the hardware uses a different interrupt numbering.
66 */
67void __init arch_init_irq(void)
68{
69	init_i8259_irqs();			/* Integrated i8259  */
70	init_r4030_ints();
71
72	change_c0_status(ST0_IM, IE_IRQ4 | IE_IRQ3 | IE_IRQ2 | IE_IRQ1);
73}
74
75static void loc_call(unsigned int irq, unsigned int mask)
76{
77	r4030_write_reg16(JAZZ_IO_IRQ_ENABLE,
78	                  r4030_read_reg16(JAZZ_IO_IRQ_ENABLE) & mask);
79	do_IRQ(irq);
80	r4030_write_reg16(JAZZ_IO_IRQ_ENABLE,
81	                  r4030_read_reg16(JAZZ_IO_IRQ_ENABLE) | mask);
82}
83
84static void ll_local_dev(void)
85{
86	switch (r4030_read_reg32(JAZZ_IO_IRQ_SOURCE)) {
87	case 0:
88		panic("Unimplemented loc_no_irq handler");
89		break;
90	case 4:
91		loc_call(JAZZ_PARALLEL_IRQ, JAZZ_IE_PARALLEL);
92		break;
93	case 8:
94		loc_call(JAZZ_PARALLEL_IRQ, JAZZ_IE_FLOPPY);
95		break;
96	case 12:
97		panic("Unimplemented loc_sound handler");
98		break;
99	case 16:
100		panic("Unimplemented loc_video handler");
101		break;
102	case 20:
103		loc_call(JAZZ_ETHERNET_IRQ, JAZZ_IE_ETHERNET);
104		break;
105	case 24:
106		loc_call(JAZZ_SCSI_IRQ, JAZZ_IE_SCSI);
107		break;
108	case 28:
109		loc_call(JAZZ_KEYBOARD_IRQ, JAZZ_IE_KEYBOARD);
110		break;
111	case 32:
112		loc_call(JAZZ_MOUSE_IRQ, JAZZ_IE_MOUSE);
113		break;
114	case 36:
115		loc_call(JAZZ_SERIAL1_IRQ, JAZZ_IE_SERIAL1);
116		break;
117	case 40:
118		loc_call(JAZZ_SERIAL2_IRQ, JAZZ_IE_SERIAL2);
119		break;
120	}
121}
122
123asmlinkage void plat_irq_dispatch(void)
124{
125	unsigned int pending = read_c0_cause() & read_c0_status();
126
127	if (pending & IE_IRQ5)
128		write_c0_compare(0);
129	else if (pending & IE_IRQ4) {
130		r4030_read_reg32(JAZZ_TIMER_REGISTER);
131		do_IRQ(JAZZ_TIMER_IRQ);
132	} else if (pending & IE_IRQ3)
133		panic("Unimplemented ISA NMI handler");
134	else if (pending & IE_IRQ2)
135		do_IRQ(r4030_read_reg32(JAZZ_EISA_IRQ_ACK));
136	else if (pending & IE_IRQ1) {
137		ll_local_dev();
138	} else if (unlikely(pending & IE_IRQ0))
139		panic("Unimplemented local_dma handler");
140	else if (pending & IE_SW1) {
141		clear_c0_cause(IE_SW1);
142		panic("Unimplemented sw1 handler");
143	} else if (pending & IE_SW0) {
144		clear_c0_cause(IE_SW0);
145		panic("Unimplemented sw0 handler");
146	}
147}
148