xref: /openbmc/linux/arch/mips/loongson32/common/irq.c (revision c8ec3743)
1 /*
2  * Copyright (c) 2011 Zhang, Keguang <keguang.zhang@gmail.com>
3  *
4  * This program is free software; you can redistribute	it and/or modify it
5  * under  the terms of	the GNU General	 Public License as published by the
6  * Free Software Foundation;  either version 2 of the  License, or (at your
7  * option) any later version.
8  */
9 
10 #include <linux/interrupt.h>
11 #include <linux/irq.h>
12 #include <asm/irq_cpu.h>
13 
14 #include <loongson1.h>
15 #include <irq.h>
16 
17 #define LS1X_INTC_REG(n, x) \
18 		((void __iomem *)KSEG1ADDR(LS1X_INTC_BASE + (n * 0x18) + (x)))
19 
20 #define LS1X_INTC_INTISR(n)		LS1X_INTC_REG(n, 0x0)
21 #define LS1X_INTC_INTIEN(n)		LS1X_INTC_REG(n, 0x4)
22 #define LS1X_INTC_INTSET(n)		LS1X_INTC_REG(n, 0x8)
23 #define LS1X_INTC_INTCLR(n)		LS1X_INTC_REG(n, 0xc)
24 #define LS1X_INTC_INTPOL(n)		LS1X_INTC_REG(n, 0x10)
25 #define LS1X_INTC_INTEDGE(n)		LS1X_INTC_REG(n, 0x14)
26 
27 static void ls1x_irq_ack(struct irq_data *d)
28 {
29 	unsigned int bit = (d->irq - LS1X_IRQ_BASE) & 0x1f;
30 	unsigned int n = (d->irq - LS1X_IRQ_BASE) >> 5;
31 
32 	__raw_writel(__raw_readl(LS1X_INTC_INTCLR(n))
33 			| (1 << bit), LS1X_INTC_INTCLR(n));
34 }
35 
36 static void ls1x_irq_mask(struct irq_data *d)
37 {
38 	unsigned int bit = (d->irq - LS1X_IRQ_BASE) & 0x1f;
39 	unsigned int n = (d->irq - LS1X_IRQ_BASE) >> 5;
40 
41 	__raw_writel(__raw_readl(LS1X_INTC_INTIEN(n))
42 			& ~(1 << bit), LS1X_INTC_INTIEN(n));
43 }
44 
45 static void ls1x_irq_mask_ack(struct irq_data *d)
46 {
47 	unsigned int bit = (d->irq - LS1X_IRQ_BASE) & 0x1f;
48 	unsigned int n = (d->irq - LS1X_IRQ_BASE) >> 5;
49 
50 	__raw_writel(__raw_readl(LS1X_INTC_INTIEN(n))
51 			& ~(1 << bit), LS1X_INTC_INTIEN(n));
52 	__raw_writel(__raw_readl(LS1X_INTC_INTCLR(n))
53 			| (1 << bit), LS1X_INTC_INTCLR(n));
54 }
55 
56 static void ls1x_irq_unmask(struct irq_data *d)
57 {
58 	unsigned int bit = (d->irq - LS1X_IRQ_BASE) & 0x1f;
59 	unsigned int n = (d->irq - LS1X_IRQ_BASE) >> 5;
60 
61 	__raw_writel(__raw_readl(LS1X_INTC_INTIEN(n))
62 			| (1 << bit), LS1X_INTC_INTIEN(n));
63 }
64 
65 static int ls1x_irq_settype(struct irq_data *d, unsigned int type)
66 {
67 	unsigned int bit = (d->irq - LS1X_IRQ_BASE) & 0x1f;
68 	unsigned int n = (d->irq - LS1X_IRQ_BASE) >> 5;
69 
70 	switch (type) {
71 	case IRQ_TYPE_LEVEL_HIGH:
72 		__raw_writel(__raw_readl(LS1X_INTC_INTPOL(n))
73 			| (1 << bit), LS1X_INTC_INTPOL(n));
74 		__raw_writel(__raw_readl(LS1X_INTC_INTEDGE(n))
75 			& ~(1 << bit), LS1X_INTC_INTEDGE(n));
76 		break;
77 	case IRQ_TYPE_LEVEL_LOW:
78 		__raw_writel(__raw_readl(LS1X_INTC_INTPOL(n))
79 			& ~(1 << bit), LS1X_INTC_INTPOL(n));
80 		__raw_writel(__raw_readl(LS1X_INTC_INTEDGE(n))
81 			& ~(1 << bit), LS1X_INTC_INTEDGE(n));
82 		break;
83 	case IRQ_TYPE_EDGE_RISING:
84 		__raw_writel(__raw_readl(LS1X_INTC_INTPOL(n))
85 			| (1 << bit), LS1X_INTC_INTPOL(n));
86 		__raw_writel(__raw_readl(LS1X_INTC_INTEDGE(n))
87 			| (1 << bit), LS1X_INTC_INTEDGE(n));
88 		break;
89 	case IRQ_TYPE_EDGE_FALLING:
90 		__raw_writel(__raw_readl(LS1X_INTC_INTPOL(n))
91 			& ~(1 << bit), LS1X_INTC_INTPOL(n));
92 		__raw_writel(__raw_readl(LS1X_INTC_INTEDGE(n))
93 			| (1 << bit), LS1X_INTC_INTEDGE(n));
94 		break;
95 	case IRQ_TYPE_EDGE_BOTH:
96 		__raw_writel(__raw_readl(LS1X_INTC_INTPOL(n))
97 			& ~(1 << bit), LS1X_INTC_INTPOL(n));
98 		__raw_writel(__raw_readl(LS1X_INTC_INTEDGE(n))
99 			| (1 << bit), LS1X_INTC_INTEDGE(n));
100 		break;
101 	case IRQ_TYPE_NONE:
102 		break;
103 	default:
104 		return -EINVAL;
105 	}
106 
107 	return 0;
108 }
109 
110 static struct irq_chip ls1x_irq_chip = {
111 	.name		= "LS1X-INTC",
112 	.irq_ack	= ls1x_irq_ack,
113 	.irq_mask	= ls1x_irq_mask,
114 	.irq_mask_ack	= ls1x_irq_mask_ack,
115 	.irq_unmask	= ls1x_irq_unmask,
116 	.irq_set_type   = ls1x_irq_settype,
117 };
118 
119 static void ls1x_irq_dispatch(int n)
120 {
121 	u32 int_status, irq;
122 
123 	/* Get pending sources, masked by current enables */
124 	int_status = __raw_readl(LS1X_INTC_INTISR(n)) &
125 			__raw_readl(LS1X_INTC_INTIEN(n));
126 
127 	if (int_status) {
128 		irq = LS1X_IRQ(n, __ffs(int_status));
129 		do_IRQ(irq);
130 	}
131 }
132 
133 asmlinkage void plat_irq_dispatch(void)
134 {
135 	unsigned int pending;
136 
137 	pending = read_c0_cause() & read_c0_status() & ST0_IM;
138 
139 	if (pending & CAUSEF_IP7)
140 		do_IRQ(TIMER_IRQ);
141 	else if (pending & CAUSEF_IP2)
142 		ls1x_irq_dispatch(0); /* INT0 */
143 	else if (pending & CAUSEF_IP3)
144 		ls1x_irq_dispatch(1); /* INT1 */
145 	else if (pending & CAUSEF_IP4)
146 		ls1x_irq_dispatch(2); /* INT2 */
147 	else if (pending & CAUSEF_IP5)
148 		ls1x_irq_dispatch(3); /* INT3 */
149 	else if (pending & CAUSEF_IP6)
150 		ls1x_irq_dispatch(4); /* INT4 */
151 	else
152 		spurious_interrupt();
153 
154 }
155 
156 static struct irqaction cascade_irqaction = {
157 	.handler = no_action,
158 	.name = "cascade",
159 	.flags = IRQF_NO_THREAD,
160 };
161 
162 static void __init ls1x_irq_init(int base)
163 {
164 	int n;
165 
166 	/* Disable interrupts and clear pending,
167 	 * setup all IRQs as high level triggered
168 	 */
169 	for (n = 0; n < INTN; n++) {
170 		__raw_writel(0x0, LS1X_INTC_INTIEN(n));
171 		__raw_writel(0xffffffff, LS1X_INTC_INTCLR(n));
172 		__raw_writel(0xffffffff, LS1X_INTC_INTPOL(n));
173 		/* set DMA0, DMA1 and DMA2 to edge trigger */
174 		__raw_writel(n ? 0x0 : 0xe000, LS1X_INTC_INTEDGE(n));
175 	}
176 
177 
178 	for (n = base; n < NR_IRQS; n++) {
179 		irq_set_chip_and_handler(n, &ls1x_irq_chip,
180 					 handle_level_irq);
181 	}
182 
183 	setup_irq(INT0_IRQ, &cascade_irqaction);
184 	setup_irq(INT1_IRQ, &cascade_irqaction);
185 	setup_irq(INT2_IRQ, &cascade_irqaction);
186 	setup_irq(INT3_IRQ, &cascade_irqaction);
187 #if defined(CONFIG_LOONGSON1_LS1C)
188 	setup_irq(INT4_IRQ, &cascade_irqaction);
189 #endif
190 }
191 
192 void __init arch_init_irq(void)
193 {
194 	mips_cpu_irq_init();
195 	ls1x_irq_init(LS1X_IRQ_BASE);
196 }
197