xref: /linux/drivers/irqchip/irq-aspeed-intc.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  Aspeed Interrupt Controller.
4  *
5  *  Copyright (C) 2023 ASPEED Technology Inc.
6  */
7 
8 #include <linux/bitops.h>
9 #include <linux/irq.h>
10 #include <linux/irqchip.h>
11 #include <linux/irqchip/chained_irq.h>
12 #include <linux/irqdomain.h>
13 #include <linux/of_address.h>
14 #include <linux/of_irq.h>
15 #include <linux/io.h>
16 #include <linux/spinlock.h>
17 
18 #define INTC_INT_ENABLE_REG	0x00
19 #define INTC_INT_STATUS_REG	0x04
20 #define INTC_IRQS_PER_WORD	32
21 
22 struct aspeed_intc_ic {
23 	void __iomem		*base;
24 	raw_spinlock_t		gic_lock;
25 	raw_spinlock_t		intc_lock;
26 	struct irq_domain	*irq_domain;
27 };
28 
29 static void aspeed_intc_ic_irq_handler(struct irq_desc *desc)
30 {
31 	struct aspeed_intc_ic *intc_ic = irq_desc_get_handler_data(desc);
32 	struct irq_chip *chip = irq_desc_get_chip(desc);
33 
34 	chained_irq_enter(chip, desc);
35 
36 	scoped_guard(raw_spinlock, &intc_ic->gic_lock) {
37 		unsigned long bit, status;
38 
39 		status = readl(intc_ic->base + INTC_INT_STATUS_REG);
40 		for_each_set_bit(bit, &status, INTC_IRQS_PER_WORD) {
41 			generic_handle_domain_irq(intc_ic->irq_domain, bit);
42 			writel(BIT(bit), intc_ic->base + INTC_INT_STATUS_REG);
43 		}
44 	}
45 
46 	chained_irq_exit(chip, desc);
47 }
48 
49 static void aspeed_intc_irq_mask(struct irq_data *data)
50 {
51 	struct aspeed_intc_ic *intc_ic = irq_data_get_irq_chip_data(data);
52 	unsigned int mask = readl(intc_ic->base + INTC_INT_ENABLE_REG) & ~BIT(data->hwirq);
53 
54 	guard(raw_spinlock)(&intc_ic->intc_lock);
55 	writel(mask, intc_ic->base + INTC_INT_ENABLE_REG);
56 }
57 
58 static void aspeed_intc_irq_unmask(struct irq_data *data)
59 {
60 	struct aspeed_intc_ic *intc_ic = irq_data_get_irq_chip_data(data);
61 	unsigned int unmask = readl(intc_ic->base + INTC_INT_ENABLE_REG) | BIT(data->hwirq);
62 
63 	guard(raw_spinlock)(&intc_ic->intc_lock);
64 	writel(unmask, intc_ic->base + INTC_INT_ENABLE_REG);
65 }
66 
67 static struct irq_chip aspeed_intc_chip = {
68 	.name			= "ASPEED INTC",
69 	.irq_mask		= aspeed_intc_irq_mask,
70 	.irq_unmask		= aspeed_intc_irq_unmask,
71 };
72 
73 static int aspeed_intc_ic_map_irq_domain(struct irq_domain *domain, unsigned int irq,
74 					 irq_hw_number_t hwirq)
75 {
76 	irq_set_chip_and_handler(irq, &aspeed_intc_chip, handle_level_irq);
77 	irq_set_chip_data(irq, domain->host_data);
78 
79 	return 0;
80 }
81 
82 static const struct irq_domain_ops aspeed_intc_ic_irq_domain_ops = {
83 	.map = aspeed_intc_ic_map_irq_domain,
84 };
85 
86 static int __init aspeed_intc_ic_of_init(struct device_node *node,
87 					 struct device_node *parent)
88 {
89 	struct aspeed_intc_ic *intc_ic;
90 	int irq, i, ret = 0;
91 
92 	intc_ic = kzalloc(sizeof(*intc_ic), GFP_KERNEL);
93 	if (!intc_ic)
94 		return -ENOMEM;
95 
96 	intc_ic->base = of_iomap(node, 0);
97 	if (!intc_ic->base) {
98 		pr_err("Failed to iomap intc_ic base\n");
99 		ret = -ENOMEM;
100 		goto err_free_ic;
101 	}
102 	writel(0xffffffff, intc_ic->base + INTC_INT_STATUS_REG);
103 	writel(0x0, intc_ic->base + INTC_INT_ENABLE_REG);
104 
105 	intc_ic->irq_domain = irq_domain_add_linear(node, INTC_IRQS_PER_WORD,
106 						    &aspeed_intc_ic_irq_domain_ops, intc_ic);
107 	if (!intc_ic->irq_domain) {
108 		ret = -ENOMEM;
109 		goto err_iounmap;
110 	}
111 
112 	raw_spin_lock_init(&intc_ic->gic_lock);
113 	raw_spin_lock_init(&intc_ic->intc_lock);
114 
115 	/* Check all the irq numbers valid. If not, unmaps all the base and frees the data. */
116 	for (i = 0; i < of_irq_count(node); i++) {
117 		irq = irq_of_parse_and_map(node, i);
118 		if (!irq) {
119 			pr_err("Failed to get irq number\n");
120 			ret = -EINVAL;
121 			goto err_iounmap;
122 		}
123 	}
124 
125 	for (i = 0; i < of_irq_count(node); i++) {
126 		irq = irq_of_parse_and_map(node, i);
127 		irq_set_chained_handler_and_data(irq, aspeed_intc_ic_irq_handler, intc_ic);
128 	}
129 
130 	return 0;
131 
132 err_iounmap:
133 	iounmap(intc_ic->base);
134 err_free_ic:
135 	kfree(intc_ic);
136 	return ret;
137 }
138 
139 IRQCHIP_DECLARE(ast2700_intc_ic, "aspeed,ast2700-intc-ic", aspeed_intc_ic_of_init);
140