1 /*
2 * GT641xx IRQ routines.
3 *
4 * Copyright (C) 2007 Yoichi Yuasa <yuasa@linux-mips.org>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20 #include <linux/hardirq.h>
21 #include <linux/init.h>
22 #include <linux/irq.h>
23 #include <linux/spinlock.h>
24 #include <linux/types.h>
25
26 #include <asm/gt64120.h>
27
28 #define GT641XX_IRQ_TO_BIT(irq) (1U << (irq - GT641XX_IRQ_BASE))
29
30 static DEFINE_RAW_SPINLOCK(gt641xx_irq_lock);
31
ack_gt641xx_irq(struct irq_data * d)32 static void ack_gt641xx_irq(struct irq_data *d)
33 {
34 unsigned long flags;
35 u32 cause;
36
37 raw_spin_lock_irqsave(>641xx_irq_lock, flags);
38 cause = GT_READ(GT_INTRCAUSE_OFS);
39 cause &= ~GT641XX_IRQ_TO_BIT(d->irq);
40 GT_WRITE(GT_INTRCAUSE_OFS, cause);
41 raw_spin_unlock_irqrestore(>641xx_irq_lock, flags);
42 }
43
mask_gt641xx_irq(struct irq_data * d)44 static void mask_gt641xx_irq(struct irq_data *d)
45 {
46 unsigned long flags;
47 u32 mask;
48
49 raw_spin_lock_irqsave(>641xx_irq_lock, flags);
50 mask = GT_READ(GT_INTRMASK_OFS);
51 mask &= ~GT641XX_IRQ_TO_BIT(d->irq);
52 GT_WRITE(GT_INTRMASK_OFS, mask);
53 raw_spin_unlock_irqrestore(>641xx_irq_lock, flags);
54 }
55
mask_ack_gt641xx_irq(struct irq_data * d)56 static void mask_ack_gt641xx_irq(struct irq_data *d)
57 {
58 unsigned long flags;
59 u32 cause, mask;
60
61 raw_spin_lock_irqsave(>641xx_irq_lock, flags);
62 mask = GT_READ(GT_INTRMASK_OFS);
63 mask &= ~GT641XX_IRQ_TO_BIT(d->irq);
64 GT_WRITE(GT_INTRMASK_OFS, mask);
65
66 cause = GT_READ(GT_INTRCAUSE_OFS);
67 cause &= ~GT641XX_IRQ_TO_BIT(d->irq);
68 GT_WRITE(GT_INTRCAUSE_OFS, cause);
69 raw_spin_unlock_irqrestore(>641xx_irq_lock, flags);
70 }
71
unmask_gt641xx_irq(struct irq_data * d)72 static void unmask_gt641xx_irq(struct irq_data *d)
73 {
74 unsigned long flags;
75 u32 mask;
76
77 raw_spin_lock_irqsave(>641xx_irq_lock, flags);
78 mask = GT_READ(GT_INTRMASK_OFS);
79 mask |= GT641XX_IRQ_TO_BIT(d->irq);
80 GT_WRITE(GT_INTRMASK_OFS, mask);
81 raw_spin_unlock_irqrestore(>641xx_irq_lock, flags);
82 }
83
84 static struct irq_chip gt641xx_irq_chip = {
85 .name = "GT641xx",
86 .irq_ack = ack_gt641xx_irq,
87 .irq_mask = mask_gt641xx_irq,
88 .irq_mask_ack = mask_ack_gt641xx_irq,
89 .irq_unmask = unmask_gt641xx_irq,
90 };
91
gt641xx_irq_dispatch(void)92 void gt641xx_irq_dispatch(void)
93 {
94 u32 cause, mask;
95 int i;
96
97 cause = GT_READ(GT_INTRCAUSE_OFS);
98 mask = GT_READ(GT_INTRMASK_OFS);
99 cause &= mask;
100
101 /*
102 * bit0 : logical or of all the interrupt bits.
103 * bit30: logical or of bits[29:26,20:1].
104 * bit31: logical or of bits[25:1].
105 */
106 for (i = 1; i < 30; i++) {
107 if (cause & (1U << i)) {
108 do_IRQ(GT641XX_IRQ_BASE + i);
109 return;
110 }
111 }
112
113 atomic_inc(&irq_err_count);
114 }
115
gt641xx_irq_init(void)116 void __init gt641xx_irq_init(void)
117 {
118 int i;
119
120 GT_WRITE(GT_INTRMASK_OFS, 0);
121 GT_WRITE(GT_INTRCAUSE_OFS, 0);
122
123 /*
124 * bit0 : logical or of all the interrupt bits.
125 * bit30: logical or of bits[29:26,20:1].
126 * bit31: logical or of bits[25:1].
127 */
128 for (i = 1; i < 30; i++)
129 irq_set_chip_and_handler(GT641XX_IRQ_BASE + i,
130 >641xx_irq_chip, handle_level_irq);
131 }
132