xref: /openbmc/linux/arch/mips/loongson32/common/irq.c (revision c4e78957)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (c) 2011 Zhang, Keguang <keguang.zhang@gmail.com>
4  */
5 
6 #include <linux/interrupt.h>
7 #include <linux/irq.h>
8 #include <asm/irq_cpu.h>
9 
10 #include <loongson1.h>
11 #include <irq.h>
12 
13 #define LS1X_INTC_REG(n, x) \
14 		((void __iomem *)KSEG1ADDR(LS1X_INTC_BASE + (n * 0x18) + (x)))
15 
16 #define LS1X_INTC_INTISR(n)		LS1X_INTC_REG(n, 0x0)
17 #define LS1X_INTC_INTIEN(n)		LS1X_INTC_REG(n, 0x4)
18 #define LS1X_INTC_INTSET(n)		LS1X_INTC_REG(n, 0x8)
19 #define LS1X_INTC_INTCLR(n)		LS1X_INTC_REG(n, 0xc)
20 #define LS1X_INTC_INTPOL(n)		LS1X_INTC_REG(n, 0x10)
21 #define LS1X_INTC_INTEDGE(n)		LS1X_INTC_REG(n, 0x14)
22 
23 static void ls1x_irq_ack(struct irq_data *d)
24 {
25 	unsigned int bit = (d->irq - LS1X_IRQ_BASE) & 0x1f;
26 	unsigned int n = (d->irq - LS1X_IRQ_BASE) >> 5;
27 
28 	__raw_writel(__raw_readl(LS1X_INTC_INTCLR(n))
29 			| (1 << bit), LS1X_INTC_INTCLR(n));
30 }
31 
32 static void ls1x_irq_mask(struct irq_data *d)
33 {
34 	unsigned int bit = (d->irq - LS1X_IRQ_BASE) & 0x1f;
35 	unsigned int n = (d->irq - LS1X_IRQ_BASE) >> 5;
36 
37 	__raw_writel(__raw_readl(LS1X_INTC_INTIEN(n))
38 			& ~(1 << bit), LS1X_INTC_INTIEN(n));
39 }
40 
41 static void ls1x_irq_mask_ack(struct irq_data *d)
42 {
43 	unsigned int bit = (d->irq - LS1X_IRQ_BASE) & 0x1f;
44 	unsigned int n = (d->irq - LS1X_IRQ_BASE) >> 5;
45 
46 	__raw_writel(__raw_readl(LS1X_INTC_INTIEN(n))
47 			& ~(1 << bit), LS1X_INTC_INTIEN(n));
48 	__raw_writel(__raw_readl(LS1X_INTC_INTCLR(n))
49 			| (1 << bit), LS1X_INTC_INTCLR(n));
50 }
51 
52 static void ls1x_irq_unmask(struct irq_data *d)
53 {
54 	unsigned int bit = (d->irq - LS1X_IRQ_BASE) & 0x1f;
55 	unsigned int n = (d->irq - LS1X_IRQ_BASE) >> 5;
56 
57 	__raw_writel(__raw_readl(LS1X_INTC_INTIEN(n))
58 			| (1 << bit), LS1X_INTC_INTIEN(n));
59 }
60 
61 static int ls1x_irq_settype(struct irq_data *d, unsigned int type)
62 {
63 	unsigned int bit = (d->irq - LS1X_IRQ_BASE) & 0x1f;
64 	unsigned int n = (d->irq - LS1X_IRQ_BASE) >> 5;
65 
66 	switch (type) {
67 	case IRQ_TYPE_LEVEL_HIGH:
68 		__raw_writel(__raw_readl(LS1X_INTC_INTPOL(n))
69 			| (1 << bit), LS1X_INTC_INTPOL(n));
70 		__raw_writel(__raw_readl(LS1X_INTC_INTEDGE(n))
71 			& ~(1 << bit), LS1X_INTC_INTEDGE(n));
72 		break;
73 	case IRQ_TYPE_LEVEL_LOW:
74 		__raw_writel(__raw_readl(LS1X_INTC_INTPOL(n))
75 			& ~(1 << bit), LS1X_INTC_INTPOL(n));
76 		__raw_writel(__raw_readl(LS1X_INTC_INTEDGE(n))
77 			& ~(1 << bit), LS1X_INTC_INTEDGE(n));
78 		break;
79 	case IRQ_TYPE_EDGE_RISING:
80 		__raw_writel(__raw_readl(LS1X_INTC_INTPOL(n))
81 			| (1 << bit), LS1X_INTC_INTPOL(n));
82 		__raw_writel(__raw_readl(LS1X_INTC_INTEDGE(n))
83 			| (1 << bit), LS1X_INTC_INTEDGE(n));
84 		break;
85 	case IRQ_TYPE_EDGE_FALLING:
86 		__raw_writel(__raw_readl(LS1X_INTC_INTPOL(n))
87 			& ~(1 << bit), LS1X_INTC_INTPOL(n));
88 		__raw_writel(__raw_readl(LS1X_INTC_INTEDGE(n))
89 			| (1 << bit), LS1X_INTC_INTEDGE(n));
90 		break;
91 	case IRQ_TYPE_EDGE_BOTH:
92 		__raw_writel(__raw_readl(LS1X_INTC_INTPOL(n))
93 			& ~(1 << bit), LS1X_INTC_INTPOL(n));
94 		__raw_writel(__raw_readl(LS1X_INTC_INTEDGE(n))
95 			| (1 << bit), LS1X_INTC_INTEDGE(n));
96 		break;
97 	case IRQ_TYPE_NONE:
98 		break;
99 	default:
100 		return -EINVAL;
101 	}
102 
103 	return 0;
104 }
105 
106 static struct irq_chip ls1x_irq_chip = {
107 	.name		= "LS1X-INTC",
108 	.irq_ack	= ls1x_irq_ack,
109 	.irq_mask	= ls1x_irq_mask,
110 	.irq_mask_ack	= ls1x_irq_mask_ack,
111 	.irq_unmask	= ls1x_irq_unmask,
112 	.irq_set_type   = ls1x_irq_settype,
113 };
114 
115 static void ls1x_irq_dispatch(int n)
116 {
117 	u32 int_status, irq;
118 
119 	/* Get pending sources, masked by current enables */
120 	int_status = __raw_readl(LS1X_INTC_INTISR(n)) &
121 			__raw_readl(LS1X_INTC_INTIEN(n));
122 
123 	if (int_status) {
124 		irq = LS1X_IRQ(n, __ffs(int_status));
125 		do_IRQ(irq);
126 	}
127 }
128 
129 asmlinkage void plat_irq_dispatch(void)
130 {
131 	unsigned int pending;
132 
133 	pending = read_c0_cause() & read_c0_status() & ST0_IM;
134 
135 	if (pending & CAUSEF_IP7)
136 		do_IRQ(TIMER_IRQ);
137 	else if (pending & CAUSEF_IP2)
138 		ls1x_irq_dispatch(0); /* INT0 */
139 	else if (pending & CAUSEF_IP3)
140 		ls1x_irq_dispatch(1); /* INT1 */
141 	else if (pending & CAUSEF_IP4)
142 		ls1x_irq_dispatch(2); /* INT2 */
143 	else if (pending & CAUSEF_IP5)
144 		ls1x_irq_dispatch(3); /* INT3 */
145 	else if (pending & CAUSEF_IP6)
146 		ls1x_irq_dispatch(4); /* INT4 */
147 	else
148 		spurious_interrupt();
149 
150 }
151 
152 static void __init ls1x_irq_init(int base)
153 {
154 	int n;
155 
156 	/* Disable interrupts and clear pending,
157 	 * setup all IRQs as high level triggered
158 	 */
159 	for (n = 0; n < INTN; n++) {
160 		__raw_writel(0x0, LS1X_INTC_INTIEN(n));
161 		__raw_writel(0xffffffff, LS1X_INTC_INTCLR(n));
162 		__raw_writel(0xffffffff, LS1X_INTC_INTPOL(n));
163 		/* set DMA0, DMA1 and DMA2 to edge trigger */
164 		__raw_writel(n ? 0x0 : 0xe000, LS1X_INTC_INTEDGE(n));
165 	}
166 
167 
168 	for (n = base; n < NR_IRQS; n++) {
169 		irq_set_chip_and_handler(n, &ls1x_irq_chip,
170 					 handle_level_irq);
171 	}
172 
173 	if (request_irq(INT0_IRQ, no_action, IRQF_NO_THREAD, "cascade", NULL))
174 		pr_err("Failed to request irq %d (cascade)\n", INT0_IRQ);
175 	if (request_irq(INT1_IRQ, no_action, IRQF_NO_THREAD, "cascade", NULL))
176 		pr_err("Failed to request irq %d (cascade)\n", INT1_IRQ);
177 	if (request_irq(INT2_IRQ, no_action, IRQF_NO_THREAD, "cascade", NULL))
178 		pr_err("Failed to request irq %d (cascade)\n", INT2_IRQ);
179 	if (request_irq(INT3_IRQ, no_action, IRQF_NO_THREAD, "cascade", NULL))
180 		pr_err("Failed to request irq %d (cascade)\n", INT3_IRQ);
181 #if defined(CONFIG_LOONGSON1_LS1C)
182 	if (request_irq(INT4_IRQ, no_action, IRQF_NO_THREAD, "cascade", NULL))
183 		pr_err("Failed to request irq %d (cascade)\n", INT4_IRQ);
184 #endif
185 }
186 
187 void __init arch_init_irq(void)
188 {
189 	mips_cpu_irq_init();
190 	ls1x_irq_init(LS1X_IRQ_BASE);
191 }
192