xref: /linux/drivers/irqchip/irq-rda-intc.c (revision b77e0ce62d63a761ffb7f7245a215a49f5921c2f)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * RDA8810PL SoC irqchip driver
4  *
5  * Copyright RDA Microelectronics Company Limited
6  * Copyright (c) 2017 Andreas Färber
7  * Copyright (c) 2018 Manivannan Sadhasivam
8  */
9 
10 #include <linux/init.h>
11 #include <linux/interrupt.h>
12 #include <linux/irq.h>
13 #include <linux/irqchip.h>
14 #include <linux/irqdomain.h>
15 #include <linux/of_address.h>
16 
17 #include <asm/exception.h>
18 
19 #define RDA_INTC_FINALSTATUS	0x00
20 #define RDA_INTC_MASK_SET	0x08
21 #define RDA_INTC_MASK_CLR	0x0c
22 
23 #define RDA_IRQ_MASK_ALL	0xFFFFFFFF
24 
25 #define RDA_NR_IRQS 32
26 
27 static void __iomem *rda_intc_base;
28 static struct irq_domain *rda_irq_domain;
29 
30 static void rda_intc_mask_irq(struct irq_data *d)
31 {
32 	writel_relaxed(BIT(d->hwirq), rda_intc_base + RDA_INTC_MASK_CLR);
33 }
34 
35 static void rda_intc_unmask_irq(struct irq_data *d)
36 {
37 	writel_relaxed(BIT(d->hwirq), rda_intc_base + RDA_INTC_MASK_SET);
38 }
39 
40 static int rda_intc_set_type(struct irq_data *data, unsigned int flow_type)
41 {
42 	/* Hardware supports only level triggered interrupts */
43 	if ((flow_type & (IRQF_TRIGGER_HIGH | IRQF_TRIGGER_LOW)) == flow_type)
44 		return 0;
45 
46 	return -EINVAL;
47 }
48 
49 static void __exception_irq_entry rda_handle_irq(struct pt_regs *regs)
50 {
51 	u32 stat = readl_relaxed(rda_intc_base + RDA_INTC_FINALSTATUS);
52 	u32 hwirq;
53 
54 	while (stat) {
55 		hwirq = __fls(stat);
56 		handle_domain_irq(rda_irq_domain, hwirq, regs);
57 		stat &= ~BIT(hwirq);
58 	}
59 }
60 
61 static struct irq_chip rda_irq_chip = {
62 	.name		= "rda-intc",
63 	.irq_mask	= rda_intc_mask_irq,
64 	.irq_unmask	= rda_intc_unmask_irq,
65 	.irq_set_type	= rda_intc_set_type,
66 };
67 
68 static int rda_irq_map(struct irq_domain *d,
69 		       unsigned int virq, irq_hw_number_t hw)
70 {
71 	irq_set_status_flags(virq, IRQ_LEVEL);
72 	irq_set_chip_and_handler(virq, &rda_irq_chip, handle_level_irq);
73 	irq_set_chip_data(virq, d->host_data);
74 	irq_set_probe(virq);
75 
76 	return 0;
77 }
78 
79 static const struct irq_domain_ops rda_irq_domain_ops = {
80 	.map = rda_irq_map,
81 	.xlate = irq_domain_xlate_onecell,
82 };
83 
84 static int __init rda8810_intc_init(struct device_node *node,
85 				    struct device_node *parent)
86 {
87 	rda_intc_base = of_io_request_and_map(node, 0, "rda-intc");
88 	if (IS_ERR(rda_intc_base))
89 		return PTR_ERR(rda_intc_base);
90 
91 	/* Mask all interrupt sources */
92 	writel_relaxed(RDA_IRQ_MASK_ALL, rda_intc_base + RDA_INTC_MASK_CLR);
93 
94 	rda_irq_domain = irq_domain_create_linear(&node->fwnode, RDA_NR_IRQS,
95 						  &rda_irq_domain_ops,
96 						  rda_intc_base);
97 	if (!rda_irq_domain) {
98 		iounmap(rda_intc_base);
99 		return -ENOMEM;
100 	}
101 
102 	set_handle_irq(rda_handle_irq);
103 
104 	return 0;
105 }
106 
107 IRQCHIP_DECLARE(rda_intc, "rda,8810pl-intc", rda8810_intc_init);
108