1 /*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * SGI UV IRQ functions
7 *
8 * Copyright (C) 2008 Silicon Graphics, Inc. All rights reserved.
9 */
10
11 #include <linux/export.h>
12 #include <linux/rbtree.h>
13 #include <linux/slab.h>
14 #include <linux/irq.h>
15
16 #include <asm/irqdomain.h>
17 #include <asm/apic.h>
18 #include <asm/uv/uv_irq.h>
19 #include <asm/uv/uv_hub.h>
20
21 /* MMR offset and pnode of hub sourcing interrupts for a given irq */
22 struct uv_irq_2_mmr_pnode {
23 unsigned long offset;
24 int pnode;
25 };
26
27 static void uv_program_mmr(struct irq_cfg *cfg, struct uv_irq_2_mmr_pnode *info)
28 {
29 unsigned long mmr_value;
30 struct uv_IO_APIC_route_entry *entry;
31
32 BUILD_BUG_ON(sizeof(struct uv_IO_APIC_route_entry) !=
33 sizeof(unsigned long));
34
35 mmr_value = 0;
36 entry = (struct uv_IO_APIC_route_entry *)&mmr_value;
37 entry->vector = cfg->vector;
38 entry->delivery_mode = APIC_DELIVERY_MODE_FIXED;
39 entry->dest_mode = apic->dest_mode_logical;
40 entry->polarity = 0;
41 entry->trigger = 0;
42 entry->mask = 0;
43 entry->dest = cfg->dest_apicid;
44
45 uv_write_global_mmr64(info->pnode, info->offset, mmr_value);
46 }
47
48 static void uv_noop(struct irq_data *data) { }
49
50 static int
51 uv_set_irq_affinity(struct irq_data *data, const struct cpumask *mask,
52 bool force)
53 {
54 struct irq_data *parent = data->parent_data;
55 struct irq_cfg *cfg = irqd_cfg(data);
56 int ret;
57
58 ret = parent->chip->irq_set_affinity(parent, mask, force);
59 if (ret >= 0) {
60 uv_program_mmr(cfg, data->chip_data);
61 vector_schedule_cleanup(cfg);
62 }
63
64 return ret;
65 }
66
67 static struct irq_chip uv_irq_chip = {
68 .name = "UV-CORE",
69 .irq_mask = uv_noop,
70 .irq_unmask = uv_noop,
71 .irq_eoi = apic_ack_irq,
72 .irq_set_affinity = uv_set_irq_affinity,
73 };
74
75 static int uv_domain_alloc(struct irq_domain *domain, unsigned int virq,
76 unsigned int nr_irqs, void *arg)
77 {
78 struct uv_irq_2_mmr_pnode *chip_data;
79 struct irq_alloc_info *info = arg;
80 struct irq_data *irq_data = irq_domain_get_irq_data(domain, virq);
81 int ret;
82
83 if (nr_irqs > 1 || !info || info->type != X86_IRQ_ALLOC_TYPE_UV)
84 return -EINVAL;
85
86 chip_data = kmalloc_node(sizeof(*chip_data), GFP_KERNEL,
87 irq_data_get_node(irq_data));
88 if (!chip_data)
89 return -ENOMEM;
90
91 ret = irq_domain_alloc_irqs_parent(domain, virq, nr_irqs, arg);
92 if (ret >= 0) {
93 if (info->uv.limit == UV_AFFINITY_CPU)
94 irq_set_status_flags(virq, IRQ_NO_BALANCING);
95 else
96 irq_set_status_flags(virq, IRQ_MOVE_PCNTXT);
97
98 chip_data->pnode = uv_blade_to_pnode(info->uv.blade);
99 chip_data->offset = info->uv.offset;
100 irq_domain_set_info(domain, virq, virq, &uv_irq_chip, chip_data,
101 handle_percpu_irq, NULL, info->uv.name);
102 } else {
103 kfree(chip_data);
104 }
105
106 return ret;
107 }
108
109 static void uv_domain_free(struct irq_domain *domain, unsigned int virq,
110 unsigned int nr_irqs)
111 {
112 struct irq_data *irq_data = irq_domain_get_irq_data(domain, virq);
113
114 BUG_ON(nr_irqs != 1);
115 kfree(irq_data->chip_data);
116 irq_clear_status_flags(virq, IRQ_MOVE_PCNTXT);
117 irq_clear_status_flags(virq, IRQ_NO_BALANCING);
118 irq_domain_free_irqs_top(domain, virq, nr_irqs);
119 }
120
121 /*
122 * Re-target the irq to the specified CPU and enable the specified MMR located
123 * on the specified blade to allow the sending of MSIs to the specified CPU.
124 */
125 static int uv_domain_activate(struct irq_domain *domain,
126 struct irq_data *irq_data, bool reserve)
127 {
128 uv_program_mmr(irqd_cfg(irq_data), irq_data->chip_data);
129 return 0;
130 }
131
132 /*
133 * Disable the specified MMR located on the specified blade so that MSIs are
134 * longer allowed to be sent.
135 */
136 static void uv_domain_deactivate(struct irq_domain *domain,
137 struct irq_data *irq_data)
138 {
139 unsigned long mmr_value;
140 struct uv_IO_APIC_route_entry *entry;
141
142 mmr_value = 0;
143 entry = (struct uv_IO_APIC_route_entry *)&mmr_value;
144 entry->mask = 1;
145 uv_program_mmr(irqd_cfg(irq_data), irq_data->chip_data);
146 }
147
148 static const struct irq_domain_ops uv_domain_ops = {
149 .alloc = uv_domain_alloc,
150 .free = uv_domain_free,
151 .activate = uv_domain_activate,
152 .deactivate = uv_domain_deactivate,
153 };
154
155 static struct irq_domain *uv_get_irq_domain(void)
156 {
157 static struct irq_domain *uv_domain;
158 static DEFINE_MUTEX(uv_lock);
159 struct fwnode_handle *fn;
160
161 mutex_lock(&uv_lock);
162 if (uv_domain)
163 goto out;
164
165 fn = irq_domain_alloc_named_fwnode("UV-CORE");
166 if (!fn)
167 goto out;
168
169 uv_domain = irq_domain_create_hierarchy(x86_vector_domain, 0, 0, fn,
170 &uv_domain_ops, NULL);
171 if (!uv_domain)
172 irq_domain_free_fwnode(fn);
173 out:
174 mutex_unlock(&uv_lock);
175
176 return uv_domain;
177 }
178
179 /*
180 * Set up a mapping of an available irq and vector, and enable the specified
181 * MMR that defines the MSI that is to be sent to the specified CPU when an
182 * interrupt is raised.
183 */
184 int uv_setup_irq(char *irq_name, int cpu, int mmr_blade,
185 unsigned long mmr_offset, int limit)
186 {
187 struct irq_alloc_info info;
188 struct irq_domain *domain = uv_get_irq_domain();
189
190 if (!domain)
191 return -ENOMEM;
192
193 init_irq_alloc_info(&info, cpumask_of(cpu));
194 info.type = X86_IRQ_ALLOC_TYPE_UV;
195 info.uv.limit = limit;
196 info.uv.blade = mmr_blade;
197 info.uv.offset = mmr_offset;
198 info.uv.name = irq_name;
199
200 return irq_domain_alloc_irqs(domain, 1,
201 uv_blade_to_memory_nid(mmr_blade), &info);
202 }
203 EXPORT_SYMBOL_GPL(uv_setup_irq);
204
205 /*
206 * Tear down a mapping of an irq and vector, and disable the specified MMR that
207 * defined the MSI that was to be sent to the specified CPU when an interrupt
208 * was raised.
209 *
210 * Set mmr_blade and mmr_offset to what was passed in on uv_setup_irq().
211 */
212 void uv_teardown_irq(unsigned int irq)
213 {
214 irq_domain_free_irqs(irq, 1);
215 }
216 EXPORT_SYMBOL_GPL(uv_teardown_irq);
217
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