1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2016 ARM Limited, All Rights Reserved.
4 * Author: Marc Zyngier <marc.zyngier@arm.com>
5 */
6
7#include <linux/bitops.h>
8#include <linux/interrupt.h>
9#include <linux/irqchip.h>
10#include <linux/irqchip/chained_irq.h>
11#include <linux/irqchip/irq-partition-percpu.h>
12#include <linux/irqdomain.h>
13#include <linux/seq_file.h>
14#include <linux/slab.h>
15
16struct partition_desc {
17 int nr_parts;
18 struct partition_affinity *parts;
19 struct irq_domain *domain;
20 struct irq_desc *chained_desc;
21 unsigned long *bitmap;
22 struct irq_domain_ops ops;
23};
24
25static bool partition_check_cpu(struct partition_desc *part,
26 unsigned int cpu, unsigned int hwirq)
27{
28 return cpumask_test_cpu(cpu, cpumask: &part->parts[hwirq].mask);
29}
30
31static void partition_irq_mask(struct irq_data *d)
32{
33 struct partition_desc *part = irq_data_get_irq_chip_data(d);
34 struct irq_chip *chip = irq_desc_get_chip(desc: part->chained_desc);
35 struct irq_data *data = irq_desc_get_irq_data(desc: part->chained_desc);
36
37 if (partition_check_cpu(part, smp_processor_id(), hwirq: d->hwirq) &&
38 chip->irq_mask)
39 chip->irq_mask(data);
40}
41
42static void partition_irq_unmask(struct irq_data *d)
43{
44 struct partition_desc *part = irq_data_get_irq_chip_data(d);
45 struct irq_chip *chip = irq_desc_get_chip(desc: part->chained_desc);
46 struct irq_data *data = irq_desc_get_irq_data(desc: part->chained_desc);
47
48 if (partition_check_cpu(part, smp_processor_id(), hwirq: d->hwirq) &&
49 chip->irq_unmask)
50 chip->irq_unmask(data);
51}
52
53static int partition_irq_set_irqchip_state(struct irq_data *d,
54 enum irqchip_irq_state which,
55 bool val)
56{
57 struct partition_desc *part = irq_data_get_irq_chip_data(d);
58 struct irq_chip *chip = irq_desc_get_chip(desc: part->chained_desc);
59 struct irq_data *data = irq_desc_get_irq_data(desc: part->chained_desc);
60
61 if (partition_check_cpu(part, smp_processor_id(), hwirq: d->hwirq) &&
62 chip->irq_set_irqchip_state)
63 return chip->irq_set_irqchip_state(data, which, val);
64
65 return -EINVAL;
66}
67
68static int partition_irq_get_irqchip_state(struct irq_data *d,
69 enum irqchip_irq_state which,
70 bool *val)
71{
72 struct partition_desc *part = irq_data_get_irq_chip_data(d);
73 struct irq_chip *chip = irq_desc_get_chip(desc: part->chained_desc);
74 struct irq_data *data = irq_desc_get_irq_data(desc: part->chained_desc);
75
76 if (partition_check_cpu(part, smp_processor_id(), hwirq: d->hwirq) &&
77 chip->irq_get_irqchip_state)
78 return chip->irq_get_irqchip_state(data, which, val);
79
80 return -EINVAL;
81}
82
83static int partition_irq_set_type(struct irq_data *d, unsigned int type)
84{
85 struct partition_desc *part = irq_data_get_irq_chip_data(d);
86 struct irq_chip *chip = irq_desc_get_chip(desc: part->chained_desc);
87 struct irq_data *data = irq_desc_get_irq_data(desc: part->chained_desc);
88
89 if (chip->irq_set_type)
90 return chip->irq_set_type(data, type);
91
92 return -EINVAL;
93}
94
95static void partition_irq_print_chip(struct irq_data *d, struct seq_file *p)
96{
97 struct partition_desc *part = irq_data_get_irq_chip_data(d);
98 struct irq_chip *chip = irq_desc_get_chip(desc: part->chained_desc);
99 struct irq_data *data = irq_desc_get_irq_data(desc: part->chained_desc);
100
101 seq_printf(m: p, fmt: " %5s-%lu", chip->name, data->hwirq);
102}
103
104static struct irq_chip partition_irq_chip = {
105 .irq_mask = partition_irq_mask,
106 .irq_unmask = partition_irq_unmask,
107 .irq_set_type = partition_irq_set_type,
108 .irq_get_irqchip_state = partition_irq_get_irqchip_state,
109 .irq_set_irqchip_state = partition_irq_set_irqchip_state,
110 .irq_print_chip = partition_irq_print_chip,
111};
112
113static void partition_handle_irq(struct irq_desc *desc)
114{
115 struct partition_desc *part = irq_desc_get_handler_data(desc);
116 struct irq_chip *chip = irq_desc_get_chip(desc);
117 int cpu = smp_processor_id();
118 int hwirq;
119
120 chained_irq_enter(chip, desc);
121
122 for_each_set_bit(hwirq, part->bitmap, part->nr_parts) {
123 if (partition_check_cpu(part, cpu, hwirq))
124 break;
125 }
126
127 if (unlikely(hwirq == part->nr_parts))
128 handle_bad_irq(desc);
129 else
130 generic_handle_domain_irq(domain: part->domain, hwirq);
131
132 chained_irq_exit(chip, desc);
133}
134
135static int partition_domain_alloc(struct irq_domain *domain, unsigned int virq,
136 unsigned int nr_irqs, void *arg)
137{
138 int ret;
139 irq_hw_number_t hwirq;
140 unsigned int type;
141 struct irq_fwspec *fwspec = arg;
142 struct partition_desc *part;
143
144 BUG_ON(nr_irqs != 1);
145 ret = domain->ops->translate(domain, fwspec, &hwirq, &type);
146 if (ret)
147 return ret;
148
149 part = domain->host_data;
150
151 set_bit(nr: hwirq, addr: part->bitmap);
152 irq_set_chained_handler_and_data(irq: irq_desc_get_irq(desc: part->chained_desc),
153 handle: partition_handle_irq, data: part);
154 irq_set_percpu_devid_partition(irq: virq, affinity: &part->parts[hwirq].mask);
155 irq_domain_set_info(domain, virq, hwirq, chip: &partition_irq_chip, chip_data: part,
156 handler: handle_percpu_devid_irq, NULL, NULL);
157 irq_set_status_flags(irq: virq, set: IRQ_NOAUTOEN);
158
159 return 0;
160}
161
162static void partition_domain_free(struct irq_domain *domain, unsigned int virq,
163 unsigned int nr_irqs)
164{
165 struct irq_data *d;
166
167 BUG_ON(nr_irqs != 1);
168
169 d = irq_domain_get_irq_data(domain, virq);
170 irq_set_handler(irq: virq, NULL);
171 irq_domain_reset_irq_data(irq_data: d);
172}
173
174int partition_translate_id(struct partition_desc *desc, void *partition_id)
175{
176 struct partition_affinity *part = NULL;
177 int i;
178
179 for (i = 0; i < desc->nr_parts; i++) {
180 if (desc->parts[i].partition_id == partition_id) {
181 part = &desc->parts[i];
182 break;
183 }
184 }
185
186 if (WARN_ON(!part)) {
187 pr_err("Failed to find partition\n");
188 return -EINVAL;
189 }
190
191 return i;
192}
193
194struct partition_desc *partition_create_desc(struct fwnode_handle *fwnode,
195 struct partition_affinity *parts,
196 int nr_parts,
197 int chained_irq,
198 const struct irq_domain_ops *ops)
199{
200 struct partition_desc *desc;
201 struct irq_domain *d;
202
203 BUG_ON(!ops->select || !ops->translate);
204
205 desc = kzalloc(size: sizeof(*desc), GFP_KERNEL);
206 if (!desc)
207 return NULL;
208
209 desc->ops = *ops;
210 desc->ops.free = partition_domain_free;
211 desc->ops.alloc = partition_domain_alloc;
212
213 d = irq_domain_create_linear(fwnode, size: nr_parts, ops: &desc->ops, host_data: desc);
214 if (!d)
215 goto out;
216 desc->domain = d;
217
218 desc->bitmap = bitmap_zalloc(nbits: nr_parts, GFP_KERNEL);
219 if (WARN_ON(!desc->bitmap))
220 goto out;
221
222 desc->chained_desc = irq_to_desc(irq: chained_irq);
223 desc->nr_parts = nr_parts;
224 desc->parts = parts;
225
226 return desc;
227out:
228 if (d)
229 irq_domain_remove(host: d);
230 kfree(objp: desc);
231
232 return NULL;
233}
234
235struct irq_domain *partition_get_domain(struct partition_desc *dsc)
236{
237 if (dsc)
238 return dsc->domain;
239
240 return NULL;
241}
242

source code of linux/drivers/irqchip/irq-partition-percpu.c