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1/*
2 * Allwinner A1X SoCs IRQ chip driver.
3 *
4 * Copyright (C) 2012 Maxime Ripard
5 *
6 * Maxime Ripard <maxime.ripard@free-electrons.com>
7 *
8 * Based on code from
9 * Allwinner Technology Co., Ltd. <www.allwinnertech.com>
10 * Benn Huang <benn@allwinnertech.com>
11 *
12 * This file is licensed under the terms of the GNU General Public
13 * License version 2. This program is licensed "as is" without any
14 * warranty of any kind, whether express or implied.
15 */
16
17#include <linux/io.h>
18#include <linux/irq.h>
19#include <linux/of.h>
20#include <linux/of_address.h>
21#include <linux/of_irq.h>
22
23#include <asm/exception.h>
24#include <asm/mach/irq.h>
25
26#include "irqchip.h"
27
28#define SUN4I_IRQ_VECTOR_REG 0x00
29#define SUN4I_IRQ_PROTECTION_REG 0x08
30#define SUN4I_IRQ_NMI_CTRL_REG 0x0c
31#define SUN4I_IRQ_PENDING_REG(x) (0x10 + 0x4 * x)
32#define SUN4I_IRQ_FIQ_PENDING_REG(x) (0x20 + 0x4 * x)
33#define SUN4I_IRQ_ENABLE_REG(x) (0x40 + 0x4 * x)
34#define SUN4I_IRQ_MASK_REG(x) (0x50 + 0x4 * x)
35
36static void __iomem *sun4i_irq_base;
37static struct irq_domain *sun4i_irq_domain;
38
39static void __exception_irq_entry sun4i_handle_irq(struct pt_regs *regs);
40
41static void sun4i_irq_ack(struct irq_data *irqd)
42{
43 unsigned int irq = irqd_to_hwirq(irqd);
44
45 if (irq != 0)
46 return; /* Only IRQ 0 / the ENMI needs to be acked */
47
48 writel(BIT(0), sun4i_irq_base + SUN4I_IRQ_PENDING_REG(0));
49}
50
51static void sun4i_irq_mask(struct irq_data *irqd)
52{
53 unsigned int irq = irqd_to_hwirq(irqd);
54 unsigned int irq_off = irq % 32;
55 int reg = irq / 32;
56 u32 val;
57
58 val = readl(sun4i_irq_base + SUN4I_IRQ_ENABLE_REG(reg));
59 writel(val & ~(1 << irq_off),
60 sun4i_irq_base + SUN4I_IRQ_ENABLE_REG(reg));
61}
62
63static void sun4i_irq_unmask(struct irq_data *irqd)
64{
65 unsigned int irq = irqd_to_hwirq(irqd);
66 unsigned int irq_off = irq % 32;
67 int reg = irq / 32;
68 u32 val;
69
70 val = readl(sun4i_irq_base + SUN4I_IRQ_ENABLE_REG(reg));
71 writel(val | (1 << irq_off),
72 sun4i_irq_base + SUN4I_IRQ_ENABLE_REG(reg));
73}
74
75static struct irq_chip sun4i_irq_chip = {
76 .name = "sun4i_irq",
77 .irq_eoi = sun4i_irq_ack,
78 .irq_mask = sun4i_irq_mask,
79 .irq_unmask = sun4i_irq_unmask,
80 .flags = IRQCHIP_EOI_THREADED | IRQCHIP_EOI_IF_HANDLED,
81};
82
83static int sun4i_irq_map(struct irq_domain *d, unsigned int virq,
84 irq_hw_number_t hw)
85{
86 irq_set_chip_and_handler(virq, &sun4i_irq_chip, handle_fasteoi_irq);
87 set_irq_flags(virq, IRQF_VALID | IRQF_PROBE);
88
89 return 0;
90}
91
92static struct irq_domain_ops sun4i_irq_ops = {
93 .map = sun4i_irq_map,
94 .xlate = irq_domain_xlate_onecell,
95};
96
97static int __init sun4i_of_init(struct device_node *node,
98 struct device_node *parent)
99{
100 sun4i_irq_base = of_iomap(node, 0);
101 if (!sun4i_irq_base)
102 panic("%s: unable to map IC registers\n",
103 node->full_name);
104
105 /* Disable all interrupts */
106 writel(0, sun4i_irq_base + SUN4I_IRQ_ENABLE_REG(0));
107 writel(0, sun4i_irq_base + SUN4I_IRQ_ENABLE_REG(1));
108 writel(0, sun4i_irq_base + SUN4I_IRQ_ENABLE_REG(2));
109
110 /* Unmask all the interrupts, ENABLE_REG(x) is used for masking */
111 writel(0, sun4i_irq_base + SUN4I_IRQ_MASK_REG(0));
112 writel(0, sun4i_irq_base + SUN4I_IRQ_MASK_REG(1));
113 writel(0, sun4i_irq_base + SUN4I_IRQ_MASK_REG(2));
114
115 /* Clear all the pending interrupts */
116 writel(0xffffffff, sun4i_irq_base + SUN4I_IRQ_PENDING_REG(0));
117 writel(0xffffffff, sun4i_irq_base + SUN4I_IRQ_PENDING_REG(1));
118 writel(0xffffffff, sun4i_irq_base + SUN4I_IRQ_PENDING_REG(2));
119
120 /* Enable protection mode */
121 writel(0x01, sun4i_irq_base + SUN4I_IRQ_PROTECTION_REG);
122
123 /* Configure the external interrupt source type */
124 writel(0x00, sun4i_irq_base + SUN4I_IRQ_NMI_CTRL_REG);
125
126 sun4i_irq_domain = irq_domain_add_linear(node, 3 * 32,
127 &sun4i_irq_ops, NULL);
128 if (!sun4i_irq_domain)
129 panic("%s: unable to create IRQ domain\n", node->full_name);
130
131 set_handle_irq(sun4i_handle_irq);
132
133 return 0;
134}
135IRQCHIP_DECLARE(allwinner_sun4i_ic, "allwinner,sun4i-a10-ic", sun4i_of_init);
136
137static void __exception_irq_entry sun4i_handle_irq(struct pt_regs *regs)
138{
139 u32 irq, hwirq;
140
141 /*
142 * hwirq == 0 can mean one of 3 things:
143 * 1) no more irqs pending
144 * 2) irq 0 pending
145 * 3) spurious irq
146 * So if we immediately get a reading of 0, check the irq-pending reg
147 * to differentiate between 2 and 3. We only do this once to avoid
148 * the extra check in the common case of 1 hapening after having
149 * read the vector-reg once.
150 */
151 hwirq = readl(sun4i_irq_base + SUN4I_IRQ_VECTOR_REG) >> 2;
152 if (hwirq == 0 &&
153 !(readl(sun4i_irq_base + SUN4I_IRQ_PENDING_REG(0)) & BIT(0)))
154 return;
155
156 do {
157 irq = irq_find_mapping(sun4i_irq_domain, hwirq);
158 handle_IRQ(irq, regs);
159 hwirq = readl(sun4i_irq_base + SUN4I_IRQ_VECTOR_REG) >> 2;
160 } while (hwirq != 0);
161}
1/*
2 * Allwinner A1X SoCs IRQ chip driver.
3 *
4 * Copyright (C) 2012 Maxime Ripard
5 *
6 * Maxime Ripard <maxime.ripard@free-electrons.com>
7 *
8 * Based on code from
9 * Allwinner Technology Co., Ltd. <www.allwinnertech.com>
10 * Benn Huang <benn@allwinnertech.com>
11 *
12 * This file is licensed under the terms of the GNU General Public
13 * License version 2. This program is licensed "as is" without any
14 * warranty of any kind, whether express or implied.
15 */
16
17#include <linux/io.h>
18#include <linux/irq.h>
19#include <linux/irqchip.h>
20#include <linux/of.h>
21#include <linux/of_address.h>
22#include <linux/of_irq.h>
23
24#include <asm/exception.h>
25
26#define SUN4I_IRQ_VECTOR_REG 0x00
27#define SUN4I_IRQ_PROTECTION_REG 0x08
28#define SUN4I_IRQ_NMI_CTRL_REG 0x0c
29#define SUN4I_IRQ_PENDING_REG(x) (0x10 + 0x4 * x)
30#define SUN4I_IRQ_FIQ_PENDING_REG(x) (0x20 + 0x4 * x)
31#define SUN4I_IRQ_ENABLE_REG(x) (0x40 + 0x4 * x)
32#define SUN4I_IRQ_MASK_REG(x) (0x50 + 0x4 * x)
33
34static void __iomem *sun4i_irq_base;
35static struct irq_domain *sun4i_irq_domain;
36
37static void __exception_irq_entry sun4i_handle_irq(struct pt_regs *regs);
38
39static void sun4i_irq_ack(struct irq_data *irqd)
40{
41 unsigned int irq = irqd_to_hwirq(irqd);
42
43 if (irq != 0)
44 return; /* Only IRQ 0 / the ENMI needs to be acked */
45
46 writel(BIT(0), sun4i_irq_base + SUN4I_IRQ_PENDING_REG(0));
47}
48
49static void sun4i_irq_mask(struct irq_data *irqd)
50{
51 unsigned int irq = irqd_to_hwirq(irqd);
52 unsigned int irq_off = irq % 32;
53 int reg = irq / 32;
54 u32 val;
55
56 val = readl(sun4i_irq_base + SUN4I_IRQ_ENABLE_REG(reg));
57 writel(val & ~(1 << irq_off),
58 sun4i_irq_base + SUN4I_IRQ_ENABLE_REG(reg));
59}
60
61static void sun4i_irq_unmask(struct irq_data *irqd)
62{
63 unsigned int irq = irqd_to_hwirq(irqd);
64 unsigned int irq_off = irq % 32;
65 int reg = irq / 32;
66 u32 val;
67
68 val = readl(sun4i_irq_base + SUN4I_IRQ_ENABLE_REG(reg));
69 writel(val | (1 << irq_off),
70 sun4i_irq_base + SUN4I_IRQ_ENABLE_REG(reg));
71}
72
73static struct irq_chip sun4i_irq_chip = {
74 .name = "sun4i_irq",
75 .irq_eoi = sun4i_irq_ack,
76 .irq_mask = sun4i_irq_mask,
77 .irq_unmask = sun4i_irq_unmask,
78 .flags = IRQCHIP_EOI_THREADED | IRQCHIP_EOI_IF_HANDLED,
79};
80
81static int sun4i_irq_map(struct irq_domain *d, unsigned int virq,
82 irq_hw_number_t hw)
83{
84 irq_set_chip_and_handler(virq, &sun4i_irq_chip, handle_fasteoi_irq);
85 irq_set_probe(virq);
86
87 return 0;
88}
89
90static const struct irq_domain_ops sun4i_irq_ops = {
91 .map = sun4i_irq_map,
92 .xlate = irq_domain_xlate_onecell,
93};
94
95static int __init sun4i_of_init(struct device_node *node,
96 struct device_node *parent)
97{
98 sun4i_irq_base = of_iomap(node, 0);
99 if (!sun4i_irq_base)
100 panic("%s: unable to map IC registers\n",
101 node->full_name);
102
103 /* Disable all interrupts */
104 writel(0, sun4i_irq_base + SUN4I_IRQ_ENABLE_REG(0));
105 writel(0, sun4i_irq_base + SUN4I_IRQ_ENABLE_REG(1));
106 writel(0, sun4i_irq_base + SUN4I_IRQ_ENABLE_REG(2));
107
108 /* Unmask all the interrupts, ENABLE_REG(x) is used for masking */
109 writel(0, sun4i_irq_base + SUN4I_IRQ_MASK_REG(0));
110 writel(0, sun4i_irq_base + SUN4I_IRQ_MASK_REG(1));
111 writel(0, sun4i_irq_base + SUN4I_IRQ_MASK_REG(2));
112
113 /* Clear all the pending interrupts */
114 writel(0xffffffff, sun4i_irq_base + SUN4I_IRQ_PENDING_REG(0));
115 writel(0xffffffff, sun4i_irq_base + SUN4I_IRQ_PENDING_REG(1));
116 writel(0xffffffff, sun4i_irq_base + SUN4I_IRQ_PENDING_REG(2));
117
118 /* Enable protection mode */
119 writel(0x01, sun4i_irq_base + SUN4I_IRQ_PROTECTION_REG);
120
121 /* Configure the external interrupt source type */
122 writel(0x00, sun4i_irq_base + SUN4I_IRQ_NMI_CTRL_REG);
123
124 sun4i_irq_domain = irq_domain_add_linear(node, 3 * 32,
125 &sun4i_irq_ops, NULL);
126 if (!sun4i_irq_domain)
127 panic("%s: unable to create IRQ domain\n", node->full_name);
128
129 set_handle_irq(sun4i_handle_irq);
130
131 return 0;
132}
133IRQCHIP_DECLARE(allwinner_sun4i_ic, "allwinner,sun4i-a10-ic", sun4i_of_init);
134
135static void __exception_irq_entry sun4i_handle_irq(struct pt_regs *regs)
136{
137 u32 hwirq;
138
139 /*
140 * hwirq == 0 can mean one of 3 things:
141 * 1) no more irqs pending
142 * 2) irq 0 pending
143 * 3) spurious irq
144 * So if we immediately get a reading of 0, check the irq-pending reg
145 * to differentiate between 2 and 3. We only do this once to avoid
146 * the extra check in the common case of 1 hapening after having
147 * read the vector-reg once.
148 */
149 hwirq = readl(sun4i_irq_base + SUN4I_IRQ_VECTOR_REG) >> 2;
150 if (hwirq == 0 &&
151 !(readl(sun4i_irq_base + SUN4I_IRQ_PENDING_REG(0)) & BIT(0)))
152 return;
153
154 do {
155 handle_domain_irq(sun4i_irq_domain, hwirq, regs);
156 hwirq = readl(sun4i_irq_base + SUN4I_IRQ_VECTOR_REG) >> 2;
157 } while (hwirq != 0);
158}