Loading...
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
20static int ioasic_irq_base;
21
22static 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
31static 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
40static void ack_ioasic_irq(struct irq_data *d)
41{
42 mask_ioasic_irq(d);
43 fast_iob();
44}
45
46static 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
54static 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
62void __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}
1/*
2 * DEC I/O ASIC interrupts.
3 *
4 * Copyright (c) 2002, 2003, 2013 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
20static int ioasic_irq_base;
21
22static 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
31static 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
40static void ack_ioasic_irq(struct irq_data *d)
41{
42 mask_ioasic_irq(d);
43 fast_iob();
44}
45
46static 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
54static void clear_ioasic_dma_irq(struct irq_data *d)
55{
56 u32 sir;
57
58 sir = ~(1 << (d->irq - ioasic_irq_base));
59 ioasic_write(IO_REG_SIR, sir);
60 fast_iob();
61}
62
63static struct irq_chip ioasic_dma_irq_type = {
64 .name = "IO-ASIC-DMA",
65 .irq_ack = clear_ioasic_dma_irq,
66 .irq_mask = mask_ioasic_irq,
67 .irq_unmask = unmask_ioasic_irq,
68 .irq_eoi = clear_ioasic_dma_irq,
69};
70
71/*
72 * I/O ASIC implements two kinds of DMA interrupts, informational and
73 * error interrupts.
74 *
75 * The formers do not stop DMA and should be cleared as soon as possible
76 * so that if they retrigger before the handler has completed, usually as
77 * a side effect of actions taken by the handler, then they are reissued.
78 * These use the `handle_edge_irq' handler that clears the request right
79 * away.
80 *
81 * The latters stop DMA and do not resume it until the interrupt has been
82 * cleared. This cannot be done until after a corrective action has been
83 * taken and this also means they will not retrigger. Therefore they use
84 * the `handle_fasteoi_irq' handler that only clears the request on the
85 * way out. Because MIPS processor interrupt inputs, one of which the I/O
86 * ASIC is cascaded to, are level-triggered it is recommended that error
87 * DMA interrupt action handlers are registered with the IRQF_ONESHOT flag
88 * set so that they are run with the interrupt line masked.
89 *
90 * This mask has `1' bits in the positions of informational interrupts.
91 */
92#define IO_IRQ_DMA_INFO \
93 (IO_IRQ_MASK(IO_INR_SCC0A_RXDMA) | \
94 IO_IRQ_MASK(IO_INR_SCC1A_RXDMA) | \
95 IO_IRQ_MASK(IO_INR_ISDN_TXDMA) | \
96 IO_IRQ_MASK(IO_INR_ISDN_RXDMA) | \
97 IO_IRQ_MASK(IO_INR_ASC_DMA))
98
99void __init init_ioasic_irqs(int base)
100{
101 int i;
102
103 /* Mask interrupts. */
104 ioasic_write(IO_REG_SIMR, 0);
105 fast_iob();
106
107 for (i = base; i < base + IO_INR_DMA; i++)
108 irq_set_chip_and_handler(i, &ioasic_irq_type,
109 handle_level_irq);
110 for (; i < base + IO_IRQ_LINES; i++)
111 irq_set_chip_and_handler(i, &ioasic_dma_irq_type,
112 1 << (i - base) & IO_IRQ_DMA_INFO ?
113 handle_edge_irq : handle_fasteoi_irq);
114
115 ioasic_irq_base = base;
116}