1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * MPC85xx 8259 functions for DS Board Setup
4 *
5 * Author Xianghua Xiao (x.xiao@freescale.com)
6 * Roy Zang <tie-fei.zang@freescale.com>
7 *      - Add PCI/PCI Express support
8 * Copyright 2007 Freescale Semiconductor Inc.
9 */
10
11#include <linux/stddef.h>
12#include <linux/kernel.h>
13#include <linux/interrupt.h>
14#include <linux/of_irq.h>
15#include <linux/of_platform.h>
16
17#include <asm/mpic.h>
18#include <asm/i8259.h>
19
20#include "mpc85xx.h"
21
22static void mpc85xx_8259_cascade(struct irq_desc *desc)
23{
24	struct irq_chip *chip = irq_desc_get_chip(desc);
25	unsigned int cascade_irq = i8259_irq();
26
27	if (cascade_irq)
28		generic_handle_irq(cascade_irq);
29
30	chip->irq_eoi(&desc->irq_data);
31}
32
33void __init mpc85xx_8259_init(void)
34{
35	struct device_node *np;
36	struct device_node *cascade_node = NULL;
37	int cascade_irq;
38
39	/* Initialize the i8259 controller */
40	for_each_node_by_type(np, "interrupt-controller") {
41		if (of_device_is_compatible(np, "chrp,iic")) {
42			cascade_node = np;
43			break;
44		}
45	}
46
47	if (cascade_node == NULL) {
48		pr_debug("i8259: Could not find i8259 PIC\n");
49		return;
50	}
51
52	cascade_irq = irq_of_parse_and_map(cascade_node, 0);
53	if (!cascade_irq) {
54		pr_err("i8259: Failed to map cascade interrupt\n");
55		return;
56	}
57
58	pr_debug("i8259: cascade mapped to irq %d\n", cascade_irq);
59
60	i8259_init(cascade_node, 0);
61	of_node_put(cascade_node);
62
63	irq_set_chained_handler(cascade_irq, mpc85xx_8259_cascade);
64}
65