blob: 5552fc2bf28a0147550d4cb22914af9dff12d3e0 [file] [log] [blame]
Jonas Jensen4de563a2013-07-04 14:38:51 +02001/*
2 * MOXA ART SoCs IRQ chip driver.
3 *
4 * Copyright (C) 2013 Jonas Jensen
5 *
6 * Jonas Jensen <jonas.jensen@gmail.com>
7 *
8 * This file is licensed under the terms of the GNU General Public
9 * License version 2. This program is licensed "as is" without any
10 * warranty of any kind, whether express or implied.
11 */
12
13#include <linux/io.h>
14#include <linux/irq.h>
15#include <linux/of.h>
16#include <linux/of_address.h>
17#include <linux/of_irq.h>
18#include <linux/irqdomain.h>
19
20#include <asm/exception.h>
21
22#include "irqchip.h"
23
24#define IRQ_SOURCE_REG 0
25#define IRQ_MASK_REG 0x04
26#define IRQ_CLEAR_REG 0x08
27#define IRQ_MODE_REG 0x0c
28#define IRQ_LEVEL_REG 0x10
29#define IRQ_STATUS_REG 0x14
30
31#define FIQ_SOURCE_REG 0x20
32#define FIQ_MASK_REG 0x24
33#define FIQ_CLEAR_REG 0x28
34#define FIQ_MODE_REG 0x2c
35#define FIQ_LEVEL_REG 0x30
36#define FIQ_STATUS_REG 0x34
37
38
39struct moxart_irq_data {
40 void __iomem *base;
41 struct irq_domain *domain;
42 unsigned int interrupt_mask;
43};
44
45static struct moxart_irq_data intc;
46
47static asmlinkage void __exception_irq_entry handle_irq(struct pt_regs *regs)
48{
49 u32 irqstat;
50 int hwirq;
51
52 irqstat = readl(intc.base + IRQ_STATUS_REG);
53
54 while (irqstat) {
55 hwirq = ffs(irqstat) - 1;
56 handle_IRQ(irq_linear_revmap(intc.domain, hwirq), regs);
57 irqstat &= ~(1 << hwirq);
58 }
59}
60
61static int __init moxart_of_intc_init(struct device_node *node,
62 struct device_node *parent)
63{
64 unsigned int clr = IRQ_NOREQUEST | IRQ_NOPROBE | IRQ_NOAUTOEN;
65 int ret;
66 struct irq_chip_generic *gc;
67
68 intc.base = of_iomap(node, 0);
69 if (!intc.base) {
70 pr_err("%s: unable to map IC registers\n",
71 node->full_name);
72 return -EINVAL;
73 }
74
75 intc.domain = irq_domain_add_linear(node, 32, &irq_generic_chip_ops,
76 intc.base);
77 if (!intc.domain) {
78 pr_err("%s: unable to create IRQ domain\n", node->full_name);
79 return -EINVAL;
80 }
81
82 ret = irq_alloc_domain_generic_chips(intc.domain, 32, 1,
83 "MOXARTINTC", handle_edge_irq,
84 clr, 0, IRQ_GC_INIT_MASK_CACHE);
85 if (ret) {
86 pr_err("%s: could not allocate generic chip\n",
87 node->full_name);
88 irq_domain_remove(intc.domain);
89 return -EINVAL;
90 }
91
92 ret = of_property_read_u32(node, "interrupt-mask",
93 &intc.interrupt_mask);
94 if (ret)
95 pr_err("%s: could not read interrupt-mask DT property\n",
96 node->full_name);
97
98 gc = irq_get_domain_generic_chip(intc.domain, 0);
99
100 gc->reg_base = intc.base;
101 gc->chip_types[0].regs.mask = IRQ_MASK_REG;
102 gc->chip_types[0].regs.ack = IRQ_CLEAR_REG;
103 gc->chip_types[0].chip.irq_ack = irq_gc_ack_set_bit;
104 gc->chip_types[0].chip.irq_mask = irq_gc_mask_clr_bit;
105 gc->chip_types[0].chip.irq_unmask = irq_gc_mask_set_bit;
106
107 writel(0, intc.base + IRQ_MASK_REG);
108 writel(0xffffffff, intc.base + IRQ_CLEAR_REG);
109
110 writel(intc.interrupt_mask, intc.base + IRQ_MODE_REG);
111 writel(intc.interrupt_mask, intc.base + IRQ_LEVEL_REG);
112
113 set_handle_irq(handle_irq);
114
115 return 0;
116}
117IRQCHIP_DECLARE(moxa_moxart_ic, "moxa,moxart-ic", moxart_of_intc_init);