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
16 struct 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
partition_check_cpu(struct partition_desc * part,unsigned int cpu,unsigned int hwirq)25 static bool partition_check_cpu(struct partition_desc *part,
26 unsigned int cpu, unsigned int hwirq)
27 {
28 return cpumask_test_cpu(cpu, &part->parts[hwirq].mask);
29 }
30
partition_irq_mask(struct irq_data * d)31 static 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(part->chained_desc);
35 struct irq_data *data = irq_desc_get_irq_data(part->chained_desc);
36
37 if (partition_check_cpu(part, smp_processor_id(), d->hwirq) &&
38 chip->irq_mask)
39 chip->irq_mask(data);
40 }
41
partition_irq_unmask(struct irq_data * d)42 static 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(part->chained_desc);
46 struct irq_data *data = irq_desc_get_irq_data(part->chained_desc);
47
48 if (partition_check_cpu(part, smp_processor_id(), d->hwirq) &&
49 chip->irq_unmask)
50 chip->irq_unmask(data);
51 }
52
partition_irq_set_irqchip_state(struct irq_data * d,enum irqchip_irq_state which,bool val)53 static 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(part->chained_desc);
59 struct irq_data *data = irq_desc_get_irq_data(part->chained_desc);
60
61 if (partition_check_cpu(part, smp_processor_id(), d->hwirq) &&
62 chip->irq_set_irqchip_state)
63 return chip->irq_set_irqchip_state(data, which, val);
64
65 return -EINVAL;
66 }
67
partition_irq_get_irqchip_state(struct irq_data * d,enum irqchip_irq_state which,bool * val)68 static 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(part->chained_desc);
74 struct irq_data *data = irq_desc_get_irq_data(part->chained_desc);
75
76 if (partition_check_cpu(part, smp_processor_id(), d->hwirq) &&
77 chip->irq_get_irqchip_state)
78 return chip->irq_get_irqchip_state(data, which, val);
79
80 return -EINVAL;
81 }
82
partition_irq_set_type(struct irq_data * d,unsigned int type)83 static 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(part->chained_desc);
87 struct irq_data *data = irq_desc_get_irq_data(part->chained_desc);
88
89 if (chip->irq_set_type)
90 return chip->irq_set_type(data, type);
91
92 return -EINVAL;
93 }
94
partition_irq_print_chip(struct irq_data * d,struct seq_file * p)95 static 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(part->chained_desc);
99 struct irq_data *data = irq_desc_get_irq_data(part->chained_desc);
100
101 seq_printf(p, " %5s-%lu", chip->name, data->hwirq);
102 }
103
104 static 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
partition_handle_irq(struct irq_desc * desc)113 static 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 unsigned int irq;
131 irq = irq_find_mapping(part->domain, hwirq);
132 generic_handle_irq(irq);
133 }
134
135 chained_irq_exit(chip, desc);
136 }
137
partition_domain_alloc(struct irq_domain * domain,unsigned int virq,unsigned int nr_irqs,void * arg)138 static int partition_domain_alloc(struct irq_domain *domain, unsigned int virq,
139 unsigned int nr_irqs, void *arg)
140 {
141 int ret;
142 irq_hw_number_t hwirq;
143 unsigned int type;
144 struct irq_fwspec *fwspec = arg;
145 struct partition_desc *part;
146
147 BUG_ON(nr_irqs != 1);
148 ret = domain->ops->translate(domain, fwspec, &hwirq, &type);
149 if (ret)
150 return ret;
151
152 part = domain->host_data;
153
154 set_bit(hwirq, part->bitmap);
155 irq_set_chained_handler_and_data(irq_desc_get_irq(part->chained_desc),
156 partition_handle_irq, part);
157 irq_set_percpu_devid_partition(virq, &part->parts[hwirq].mask);
158 irq_domain_set_info(domain, virq, hwirq, &partition_irq_chip, part,
159 handle_percpu_devid_irq, NULL, NULL);
160 irq_set_status_flags(virq, IRQ_NOAUTOEN);
161
162 return 0;
163 }
164
partition_domain_free(struct irq_domain * domain,unsigned int virq,unsigned int nr_irqs)165 static void partition_domain_free(struct irq_domain *domain, unsigned int virq,
166 unsigned int nr_irqs)
167 {
168 struct irq_data *d;
169
170 BUG_ON(nr_irqs != 1);
171
172 d = irq_domain_get_irq_data(domain, virq);
173 irq_set_handler(virq, NULL);
174 irq_domain_reset_irq_data(d);
175 }
176
partition_translate_id(struct partition_desc * desc,void * partition_id)177 int partition_translate_id(struct partition_desc *desc, void *partition_id)
178 {
179 struct partition_affinity *part = NULL;
180 int i;
181
182 for (i = 0; i < desc->nr_parts; i++) {
183 if (desc->parts[i].partition_id == partition_id) {
184 part = &desc->parts[i];
185 break;
186 }
187 }
188
189 if (WARN_ON(!part)) {
190 pr_err("Failed to find partition\n");
191 return -EINVAL;
192 }
193
194 return i;
195 }
196
partition_create_desc(struct fwnode_handle * fwnode,struct partition_affinity * parts,int nr_parts,int chained_irq,const struct irq_domain_ops * ops)197 struct partition_desc *partition_create_desc(struct fwnode_handle *fwnode,
198 struct partition_affinity *parts,
199 int nr_parts,
200 int chained_irq,
201 const struct irq_domain_ops *ops)
202 {
203 struct partition_desc *desc;
204 struct irq_domain *d;
205
206 BUG_ON(!ops->select || !ops->translate);
207
208 desc = kzalloc(sizeof(*desc), GFP_KERNEL);
209 if (!desc)
210 return NULL;
211
212 desc->ops = *ops;
213 desc->ops.free = partition_domain_free;
214 desc->ops.alloc = partition_domain_alloc;
215
216 d = irq_domain_create_linear(fwnode, nr_parts, &desc->ops, desc);
217 if (!d)
218 goto out;
219 desc->domain = d;
220
221 desc->bitmap = kcalloc(BITS_TO_LONGS(nr_parts), sizeof(long),
222 GFP_KERNEL);
223 if (WARN_ON(!desc->bitmap))
224 goto out;
225
226 desc->chained_desc = irq_to_desc(chained_irq);
227 desc->nr_parts = nr_parts;
228 desc->parts = parts;
229
230 return desc;
231 out:
232 if (d)
233 irq_domain_remove(d);
234 kfree(desc);
235
236 return NULL;
237 }
238
partition_get_domain(struct partition_desc * dsc)239 struct irq_domain *partition_get_domain(struct partition_desc *dsc)
240 {
241 if (dsc)
242 return dsc->domain;
243
244 return NULL;
245 }
246