xref: /OK3568_Linux_fs/kernel/arch/nios2/kernel/irq.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-or-later
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun  * Copyright (C) 2013 Altera Corporation
4*4882a593Smuzhiyun  * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>
5*4882a593Smuzhiyun  * Copyright (C) 2008 Thomas Chou <thomas@wytron.com.tw>
6*4882a593Smuzhiyun  *
7*4882a593Smuzhiyun  * based on irq.c from m68k which is:
8*4882a593Smuzhiyun  *
9*4882a593Smuzhiyun  * Copyright (C) 2007 Greg Ungerer <gerg@snapgear.com>
10*4882a593Smuzhiyun  */
11*4882a593Smuzhiyun 
12*4882a593Smuzhiyun #include <linux/init.h>
13*4882a593Smuzhiyun #include <linux/interrupt.h>
14*4882a593Smuzhiyun #include <linux/of.h>
15*4882a593Smuzhiyun 
16*4882a593Smuzhiyun static u32 ienable;
17*4882a593Smuzhiyun 
do_IRQ(int hwirq,struct pt_regs * regs)18*4882a593Smuzhiyun asmlinkage void do_IRQ(int hwirq, struct pt_regs *regs)
19*4882a593Smuzhiyun {
20*4882a593Smuzhiyun 	struct pt_regs *oldregs = set_irq_regs(regs);
21*4882a593Smuzhiyun 	int irq;
22*4882a593Smuzhiyun 
23*4882a593Smuzhiyun 	irq_enter();
24*4882a593Smuzhiyun 	irq = irq_find_mapping(NULL, hwirq);
25*4882a593Smuzhiyun 	generic_handle_irq(irq);
26*4882a593Smuzhiyun 	irq_exit();
27*4882a593Smuzhiyun 
28*4882a593Smuzhiyun 	set_irq_regs(oldregs);
29*4882a593Smuzhiyun }
30*4882a593Smuzhiyun 
chip_unmask(struct irq_data * d)31*4882a593Smuzhiyun static void chip_unmask(struct irq_data *d)
32*4882a593Smuzhiyun {
33*4882a593Smuzhiyun 	ienable |= (1 << d->hwirq);
34*4882a593Smuzhiyun 	WRCTL(CTL_IENABLE, ienable);
35*4882a593Smuzhiyun }
36*4882a593Smuzhiyun 
chip_mask(struct irq_data * d)37*4882a593Smuzhiyun static void chip_mask(struct irq_data *d)
38*4882a593Smuzhiyun {
39*4882a593Smuzhiyun 	ienable &= ~(1 << d->hwirq);
40*4882a593Smuzhiyun 	WRCTL(CTL_IENABLE, ienable);
41*4882a593Smuzhiyun }
42*4882a593Smuzhiyun 
43*4882a593Smuzhiyun static struct irq_chip m_irq_chip = {
44*4882a593Smuzhiyun 	.name		= "NIOS2-INTC",
45*4882a593Smuzhiyun 	.irq_unmask	= chip_unmask,
46*4882a593Smuzhiyun 	.irq_mask	= chip_mask,
47*4882a593Smuzhiyun };
48*4882a593Smuzhiyun 
irq_map(struct irq_domain * h,unsigned int virq,irq_hw_number_t hw_irq_num)49*4882a593Smuzhiyun static int irq_map(struct irq_domain *h, unsigned int virq,
50*4882a593Smuzhiyun 				irq_hw_number_t hw_irq_num)
51*4882a593Smuzhiyun {
52*4882a593Smuzhiyun 	irq_set_chip_and_handler(virq, &m_irq_chip, handle_level_irq);
53*4882a593Smuzhiyun 
54*4882a593Smuzhiyun 	return 0;
55*4882a593Smuzhiyun }
56*4882a593Smuzhiyun 
57*4882a593Smuzhiyun static const struct irq_domain_ops irq_ops = {
58*4882a593Smuzhiyun 	.map	= irq_map,
59*4882a593Smuzhiyun 	.xlate	= irq_domain_xlate_onecell,
60*4882a593Smuzhiyun };
61*4882a593Smuzhiyun 
init_IRQ(void)62*4882a593Smuzhiyun void __init init_IRQ(void)
63*4882a593Smuzhiyun {
64*4882a593Smuzhiyun 	struct irq_domain *domain;
65*4882a593Smuzhiyun 	struct device_node *node;
66*4882a593Smuzhiyun 
67*4882a593Smuzhiyun 	node = of_find_compatible_node(NULL, NULL, "altr,nios2-1.0");
68*4882a593Smuzhiyun 	if (!node)
69*4882a593Smuzhiyun 		node = of_find_compatible_node(NULL, NULL, "altr,nios2-1.1");
70*4882a593Smuzhiyun 
71*4882a593Smuzhiyun 	BUG_ON(!node);
72*4882a593Smuzhiyun 
73*4882a593Smuzhiyun 	domain = irq_domain_add_linear(node, NIOS2_CPU_NR_IRQS, &irq_ops, NULL);
74*4882a593Smuzhiyun 	BUG_ON(!domain);
75*4882a593Smuzhiyun 
76*4882a593Smuzhiyun 	irq_set_default_host(domain);
77*4882a593Smuzhiyun 	of_node_put(node);
78*4882a593Smuzhiyun 	/* Load the initial ienable value */
79*4882a593Smuzhiyun 	ienable = RDCTL(CTL_IENABLE);
80*4882a593Smuzhiyun }
81