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7#include <linux/bitops.h>
8#include <linux/irq.h>
9#include <linux/of_address.h>
10#include <linux/of_irq.h>
11#include <linux/irqchip.h>
12#include <linux/irqchip/chained_irq.h>
13#include <linux/interrupt.h>
14
15#define ICPU_CFG_INTR_INTR_STICKY 0x10
16#define ICPU_CFG_INTR_INTR_ENA 0x18
17#define ICPU_CFG_INTR_INTR_ENA_CLR 0x1c
18#define ICPU_CFG_INTR_INTR_ENA_SET 0x20
19#define ICPU_CFG_INTR_DST_INTR_IDENT(x) (0x38 + 0x4 * (x))
20#define ICPU_CFG_INTR_INTR_TRIGGER(x) (0x5c + 0x4 * (x))
21
22#define OCELOT_NR_IRQ 24
23
24static void ocelot_irq_unmask(struct irq_data *data)
25{
26 struct irq_chip_generic *gc = irq_data_get_irq_chip_data(data);
27 struct irq_chip_type *ct = irq_data_get_chip_type(data);
28 unsigned int mask = data->mask;
29 u32 val;
30
31 irq_gc_lock(gc);
32 val = irq_reg_readl(gc, ICPU_CFG_INTR_INTR_TRIGGER(0)) |
33 irq_reg_readl(gc, ICPU_CFG_INTR_INTR_TRIGGER(1));
34 if (!(val & mask))
35 irq_reg_writel(gc, mask, ICPU_CFG_INTR_INTR_STICKY);
36
37 *ct->mask_cache &= ~mask;
38 irq_reg_writel(gc, mask, ICPU_CFG_INTR_INTR_ENA_SET);
39 irq_gc_unlock(gc);
40}
41
42static void ocelot_irq_handler(struct irq_desc *desc)
43{
44 struct irq_chip *chip = irq_desc_get_chip(desc);
45 struct irq_domain *d = irq_desc_get_handler_data(desc);
46 struct irq_chip_generic *gc = irq_get_domain_generic_chip(d, 0);
47 u32 reg = irq_reg_readl(gc, ICPU_CFG_INTR_DST_INTR_IDENT(0));
48
49 chained_irq_enter(chip, desc);
50
51 while (reg) {
52 u32 hwirq = __fls(reg);
53
54 generic_handle_irq(irq_find_mapping(d, hwirq));
55 reg &= ~(BIT(hwirq));
56 }
57
58 chained_irq_exit(chip, desc);
59}
60
61static int __init ocelot_irq_init(struct device_node *node,
62 struct device_node *parent)
63{
64 struct irq_domain *domain;
65 struct irq_chip_generic *gc;
66 int parent_irq, ret;
67
68 parent_irq = irq_of_parse_and_map(node, 0);
69 if (!parent_irq)
70 return -EINVAL;
71
72 domain = irq_domain_add_linear(node, OCELOT_NR_IRQ,
73 &irq_generic_chip_ops, NULL);
74 if (!domain) {
75 pr_err("%s: unable to add irq domain\n", node->name);
76 return -ENOMEM;
77 }
78
79 ret = irq_alloc_domain_generic_chips(domain, OCELOT_NR_IRQ, 1,
80 "icpu", handle_level_irq,
81 0, 0, 0);
82 if (ret) {
83 pr_err("%s: unable to alloc irq domain gc\n", node->name);
84 goto err_domain_remove;
85 }
86
87 gc = irq_get_domain_generic_chip(domain, 0);
88 gc->reg_base = of_iomap(node, 0);
89 if (!gc->reg_base) {
90 pr_err("%s: unable to map resource\n", node->name);
91 ret = -ENOMEM;
92 goto err_gc_free;
93 }
94
95 gc->chip_types[0].regs.ack = ICPU_CFG_INTR_INTR_STICKY;
96 gc->chip_types[0].regs.mask = ICPU_CFG_INTR_INTR_ENA_CLR;
97 gc->chip_types[0].chip.irq_ack = irq_gc_ack_set_bit;
98 gc->chip_types[0].chip.irq_mask = irq_gc_mask_set_bit;
99 gc->chip_types[0].chip.irq_unmask = ocelot_irq_unmask;
100
101
102 irq_reg_writel(gc, 0, ICPU_CFG_INTR_INTR_ENA);
103 irq_reg_writel(gc, 0xffffffff, ICPU_CFG_INTR_INTR_STICKY);
104
105 irq_set_chained_handler_and_data(parent_irq, ocelot_irq_handler,
106 domain);
107
108 return 0;
109
110err_gc_free:
111 irq_free_generic_chip(gc);
112
113err_domain_remove:
114 irq_domain_remove(domain);
115
116 return ret;
117}
118IRQCHIP_DECLARE(ocelot_icpu, "mscc,ocelot-icpu-intr", ocelot_irq_init);
119
