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
13 struct cpm_pic_data {
14 cpic8xx_t __iomem *reg;
15 struct irq_domain *host;
16 };
17
cpm_mask_irq(struct irq_data * d)18 static 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
cpm_unmask_irq(struct irq_data * d)26 static 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
cpm_end_irq(struct irq_data * d)34 static 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
42 static 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
cpm_get_irq(struct irq_desc * desc)49 static 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_find_mapping(data->host, cpm_vec);
63 }
64
cpm_cascade(struct irq_desc * desc)65 static void cpm_cascade(struct irq_desc *desc)
66 {
67 generic_handle_irq(cpm_get_irq(desc));
68 }
69
cpm_pic_host_map(struct irq_domain * h,unsigned int virq,irq_hw_number_t hw)70 static 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
79 static const struct irq_domain_ops cpm_pic_host_ops = {
80 .map = cpm_pic_host_map,
81 };
82
cpm_pic_probe(struct platform_device * pdev)83 static 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_create_linear(of_fwnode_handle(dev->of_node),
114 64, &cpm_pic_host_ops, data);
115 if (!data->host)
116 return -ENODEV;
117
118 irq_set_handler_data(irq, data);
119 irq_set_chained_handler(irq, cpm_cascade);
120
121 setbits32(&data->reg->cpic_cicr, CICR_IEN);
122
123 return 0;
124 }
125
126 static const struct of_device_id cpm_pic_match[] = {
127 {
128 .compatible = "fsl,cpm1-pic",
129 }, {
130 .type = "cpm-pic",
131 .compatible = "CPM",
132 }, {},
133 };
134
135 static struct platform_driver cpm_pic_driver = {
136 .driver = {
137 .name = "cpm-pic",
138 .of_match_table = cpm_pic_match,
139 },
140 .probe = cpm_pic_probe,
141 };
142
cpm_pic_init(void)143 static int __init cpm_pic_init(void)
144 {
145 return platform_driver_register(&cpm_pic_driver);
146 }
147 arch_initcall(cpm_pic_init);
148
149 /*
150 * The CPM can generate the error interrupt when there is a race condition
151 * between generating and masking interrupts. All we have to do is ACK it
152 * and return. This is a no-op function so we don't need any special
153 * tests in the interrupt handler.
154 */
cpm_error_interrupt(int irq,void * dev)155 static irqreturn_t cpm_error_interrupt(int irq, void *dev)
156 {
157 return IRQ_HANDLED;
158 }
159
cpm_error_probe(struct platform_device * pdev)160 static int cpm_error_probe(struct platform_device *pdev)
161 {
162 int irq;
163
164 irq = platform_get_irq(pdev, 0);
165 if (irq < 0)
166 return irq;
167
168 return request_irq(irq, cpm_error_interrupt, IRQF_NO_THREAD, "error", NULL);
169 }
170
171 static const struct of_device_id cpm_error_ids[] = {
172 { .compatible = "fsl,cpm1" },
173 { .type = "cpm" },
174 {},
175 };
176
177 static struct platform_driver cpm_error_driver = {
178 .driver = {
179 .name = "cpm-error",
180 .of_match_table = cpm_error_ids,
181 },
182 .probe = cpm_error_probe,
183 };
184
cpm_error_init(void)185 static int __init cpm_error_init(void)
186 {
187 return platform_driver_register(&cpm_error_driver);
188 }
189 subsys_initcall(cpm_error_init);
190