1 /*
2  *	DEC I/O ASIC interrupts.
3  *
4  *	Copyright (c) 2002, 2003  Maciej W. Rozycki
5  *
6  *	This program is free software; you can redistribute it and/or
7  *	modify it under the terms of the GNU General Public License
8  *	as published by the Free Software Foundation; either version
9  *	2 of the License, or (at your option) any later version.
10  */
11 
12 #include <linux/init.h>
13 #include <linux/irq.h>
14 #include <linux/types.h>
15 
16 #include <asm/dec/ioasic.h>
17 #include <asm/dec/ioasic_addrs.h>
18 #include <asm/dec/ioasic_ints.h>
19 
20 static int ioasic_irq_base;
21 
unmask_ioasic_irq(struct irq_data * d)22 static void unmask_ioasic_irq(struct irq_data *d)
23 {
24 	u32 simr;
25 
26 	simr = ioasic_read(IO_REG_SIMR);
27 	simr |= (1 << (d->irq - ioasic_irq_base));
28 	ioasic_write(IO_REG_SIMR, simr);
29 }
30 
mask_ioasic_irq(struct irq_data * d)31 static void mask_ioasic_irq(struct irq_data *d)
32 {
33 	u32 simr;
34 
35 	simr = ioasic_read(IO_REG_SIMR);
36 	simr &= ~(1 << (d->irq - ioasic_irq_base));
37 	ioasic_write(IO_REG_SIMR, simr);
38 }
39 
ack_ioasic_irq(struct irq_data * d)40 static void ack_ioasic_irq(struct irq_data *d)
41 {
42 	mask_ioasic_irq(d);
43 	fast_iob();
44 }
45 
46 static struct irq_chip ioasic_irq_type = {
47 	.name = "IO-ASIC",
48 	.irq_ack = ack_ioasic_irq,
49 	.irq_mask = mask_ioasic_irq,
50 	.irq_mask_ack = ack_ioasic_irq,
51 	.irq_unmask = unmask_ioasic_irq,
52 };
53 
54 static struct irq_chip ioasic_dma_irq_type = {
55 	.name = "IO-ASIC-DMA",
56 	.irq_ack = ack_ioasic_irq,
57 	.irq_mask = mask_ioasic_irq,
58 	.irq_mask_ack = ack_ioasic_irq,
59 	.irq_unmask = unmask_ioasic_irq,
60 };
61 
init_ioasic_irqs(int base)62 void __init init_ioasic_irqs(int base)
63 {
64 	int i;
65 
66 	/* Mask interrupts. */
67 	ioasic_write(IO_REG_SIMR, 0);
68 	fast_iob();
69 
70 	for (i = base; i < base + IO_INR_DMA; i++)
71 		irq_set_chip_and_handler(i, &ioasic_irq_type,
72 					 handle_level_irq);
73 	for (; i < base + IO_IRQ_LINES; i++)
74 		irq_set_chip(i, &ioasic_dma_irq_type);
75 
76 	ioasic_irq_base = base;
77 }
78