1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Interrupt controller for the
4 * Communication Processor Module.
5 * Copyright (c) 1997 Dan error_act (dmalek@jlc.net)
6 */
7#include <linux/kernel.h>
8#include <linux/interrupt.h>
9#include <linux/irqdomain.h>
10#include <linux/platform_device.h>
11#include <asm/cpm1.h>
12
13struct cpm_pic_data {
14	cpic8xx_t __iomem *reg;
15	struct irq_domain *host;
16};
17
18static void cpm_mask_irq(struct irq_data *d)
19{
20	struct cpm_pic_data *data = irq_data_get_irq_chip_data(d);
21	unsigned int cpm_vec = (unsigned int)irqd_to_hwirq(d);
22
23	clrbits32(&data->reg->cpic_cimr, (1 << cpm_vec));
24}
25
26static void cpm_unmask_irq(struct irq_data *d)
27{
28	struct cpm_pic_data *data = irq_data_get_irq_chip_data(d);
29	unsigned int cpm_vec = (unsigned int)irqd_to_hwirq(d);
30
31	setbits32(&data->reg->cpic_cimr, (1 << cpm_vec));
32}
33
34static void cpm_end_irq(struct irq_data *d)
35{
36	struct cpm_pic_data *data = irq_data_get_irq_chip_data(d);
37	unsigned int cpm_vec = (unsigned int)irqd_to_hwirq(d);
38
39	out_be32(&data->reg->cpic_cisr, (1 << cpm_vec));
40}
41
42static struct irq_chip cpm_pic = {
43	.name = "CPM PIC",
44	.irq_mask = cpm_mask_irq,
45	.irq_unmask = cpm_unmask_irq,
46	.irq_eoi = cpm_end_irq,
47};
48
49static int cpm_get_irq(struct irq_desc *desc)
50{
51	struct cpm_pic_data *data = irq_desc_get_handler_data(desc);
52	int cpm_vec;
53
54	/*
55	 * Get the vector by setting the ACK bit and then reading
56	 * the register.
57	 */
58	out_be16(&data->reg->cpic_civr, 1);
59	cpm_vec = in_be16(&data->reg->cpic_civr);
60	cpm_vec >>= 11;
61
62	return irq_linear_revmap(data->host, cpm_vec);
63}
64
65static void cpm_cascade(struct irq_desc *desc)
66{
67	generic_handle_irq(cpm_get_irq(desc));
68}
69
70static int cpm_pic_host_map(struct irq_domain *h, unsigned int virq,
71			    irq_hw_number_t hw)
72{
73	irq_set_chip_data(virq, h->host_data);
74	irq_set_status_flags(virq, IRQ_LEVEL);
75	irq_set_chip_and_handler(virq, &cpm_pic, handle_fasteoi_irq);
76	return 0;
77}
78
79static const struct irq_domain_ops cpm_pic_host_ops = {
80	.map = cpm_pic_host_map,
81};
82
83static int cpm_pic_probe(struct platform_device *pdev)
84{
85	struct device *dev = &pdev->dev;
86	struct resource *res;
87	int irq;
88	struct cpm_pic_data *data;
89
90	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
91	if (!res)
92		return -ENODEV;
93
94	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
95	if (!data)
96		return -ENOMEM;
97
98	data->reg = devm_ioremap(dev, res->start, resource_size(res));
99	if (!data->reg)
100		return -ENODEV;
101
102	irq = platform_get_irq(pdev, 0);
103	if (irq < 0)
104		return irq;
105
106	/* Initialize the CPM interrupt controller. */
107	out_be32(&data->reg->cpic_cicr,
108		 (CICR_SCD_SCC4 | CICR_SCC_SCC3 | CICR_SCB_SCC2 | CICR_SCA_SCC1) |
109		 ((virq_to_hw(irq) / 2) << 13) | CICR_HP_MASK);
110
111	out_be32(&data->reg->cpic_cimr, 0);
112
113	data->host = irq_domain_add_linear(dev->of_node, 64, &cpm_pic_host_ops, data);
114	if (!data->host)
115		return -ENODEV;
116
117	irq_set_handler_data(irq, data);
118	irq_set_chained_handler(irq, cpm_cascade);
119
120	setbits32(&data->reg->cpic_cicr, CICR_IEN);
121
122	return 0;
123}
124
125static const struct of_device_id cpm_pic_match[] = {
126	{
127		.compatible = "fsl,cpm1-pic",
128	}, {
129		.type = "cpm-pic",
130		.compatible = "CPM",
131	}, {},
132};
133
134static struct platform_driver cpm_pic_driver = {
135	.driver	= {
136		.name		= "cpm-pic",
137		.of_match_table	= cpm_pic_match,
138	},
139	.probe	= cpm_pic_probe,
140};
141
142static int __init cpm_pic_init(void)
143{
144	return platform_driver_register(&cpm_pic_driver);
145}
146arch_initcall(cpm_pic_init);
147
148/*
149 * The CPM can generate the error interrupt when there is a race condition
150 * between generating and masking interrupts.  All we have to do is ACK it
151 * and return.  This is a no-op function so we don't need any special
152 * tests in the interrupt handler.
153 */
154static irqreturn_t cpm_error_interrupt(int irq, void *dev)
155{
156	return IRQ_HANDLED;
157}
158
159static int cpm_error_probe(struct platform_device *pdev)
160{
161	int irq;
162
163	irq = platform_get_irq(pdev, 0);
164	if (irq < 0)
165		return irq;
166
167	return request_irq(irq, cpm_error_interrupt, IRQF_NO_THREAD, "error", NULL);
168}
169
170static const struct of_device_id cpm_error_ids[] = {
171	{ .compatible = "fsl,cpm1" },
172	{ .type = "cpm" },
173	{},
174};
175
176static struct platform_driver cpm_error_driver = {
177	.driver	= {
178		.name		= "cpm-error",
179		.of_match_table	= cpm_error_ids,
180	},
181	.probe	= cpm_error_probe,
182};
183
184static int __init cpm_error_init(void)
185{
186	return platform_driver_register(&cpm_error_driver);
187}
188subsys_initcall(cpm_error_init);
189