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1// SPDX-License-Identifier: GPL-2.0
2
3#include <linux/cpuhotplug.h>
4#include <linux/cpumask.h>
5#include <linux/slab.h>
6#include <linux/mm.h>
7
8#include <asm/apic.h>
9
10#include "local.h"
11
12struct cluster_mask {
13 unsigned int clusterid;
14 int node;
15 struct cpumask mask;
16};
17
18static DEFINE_PER_CPU(u32, x86_cpu_to_logical_apicid);
19static DEFINE_PER_CPU(cpumask_var_t, ipi_mask);
20static DEFINE_PER_CPU(struct cluster_mask *, cluster_masks);
21static struct cluster_mask *cluster_hotplug_mask;
22
23static int x2apic_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
24{
25 return x2apic_enabled();
26}
27
28static void x2apic_send_IPI(int cpu, int vector)
29{
30 u32 dest = per_cpu(x86_cpu_to_logical_apicid, cpu);
31
32 x2apic_wrmsr_fence();
33 __x2apic_send_IPI_dest(dest, vector, APIC_DEST_LOGICAL);
34}
35
36static void
37__x2apic_send_IPI_mask(const struct cpumask *mask, int vector, int apic_dest)
38{
39 unsigned int cpu, clustercpu;
40 struct cpumask *tmpmsk;
41 unsigned long flags;
42 u32 dest;
43
44 x2apic_wrmsr_fence();
45 local_irq_save(flags);
46
47 tmpmsk = this_cpu_cpumask_var_ptr(ipi_mask);
48 cpumask_copy(tmpmsk, mask);
49 /* If IPI should not be sent to self, clear current CPU */
50 if (apic_dest != APIC_DEST_ALLINC)
51 __cpumask_clear_cpu(smp_processor_id(), tmpmsk);
52
53 /* Collapse cpus in a cluster so a single IPI per cluster is sent */
54 for_each_cpu(cpu, tmpmsk) {
55 struct cluster_mask *cmsk = per_cpu(cluster_masks, cpu);
56
57 dest = 0;
58 for_each_cpu_and(clustercpu, tmpmsk, &cmsk->mask)
59 dest |= per_cpu(x86_cpu_to_logical_apicid, clustercpu);
60
61 if (!dest)
62 continue;
63
64 __x2apic_send_IPI_dest(dest, vector, apic->dest_logical);
65 /* Remove cluster CPUs from tmpmask */
66 cpumask_andnot(tmpmsk, tmpmsk, &cmsk->mask);
67 }
68
69 local_irq_restore(flags);
70}
71
72static void x2apic_send_IPI_mask(const struct cpumask *mask, int vector)
73{
74 __x2apic_send_IPI_mask(mask, vector, APIC_DEST_ALLINC);
75}
76
77static void
78x2apic_send_IPI_mask_allbutself(const struct cpumask *mask, int vector)
79{
80 __x2apic_send_IPI_mask(mask, vector, APIC_DEST_ALLBUT);
81}
82
83static void x2apic_send_IPI_allbutself(int vector)
84{
85 __x2apic_send_IPI_shorthand(vector, APIC_DEST_ALLBUT);
86}
87
88static void x2apic_send_IPI_all(int vector)
89{
90 __x2apic_send_IPI_shorthand(vector, APIC_DEST_ALLINC);
91}
92
93static u32 x2apic_calc_apicid(unsigned int cpu)
94{
95 return per_cpu(x86_cpu_to_logical_apicid, cpu);
96}
97
98static void init_x2apic_ldr(void)
99{
100 struct cluster_mask *cmsk = this_cpu_read(cluster_masks);
101 u32 cluster, apicid = apic_read(APIC_LDR);
102 unsigned int cpu;
103
104 this_cpu_write(x86_cpu_to_logical_apicid, apicid);
105
106 if (cmsk)
107 goto update;
108
109 cluster = apicid >> 16;
110 for_each_online_cpu(cpu) {
111 cmsk = per_cpu(cluster_masks, cpu);
112 /* Matching cluster found. Link and update it. */
113 if (cmsk && cmsk->clusterid == cluster)
114 goto update;
115 }
116 cmsk = cluster_hotplug_mask;
117 cmsk->clusterid = cluster;
118 cluster_hotplug_mask = NULL;
119update:
120 this_cpu_write(cluster_masks, cmsk);
121 cpumask_set_cpu(smp_processor_id(), &cmsk->mask);
122}
123
124static int alloc_clustermask(unsigned int cpu, int node)
125{
126 if (per_cpu(cluster_masks, cpu))
127 return 0;
128 /*
129 * If a hotplug spare mask exists, check whether it's on the right
130 * node. If not, free it and allocate a new one.
131 */
132 if (cluster_hotplug_mask) {
133 if (cluster_hotplug_mask->node == node)
134 return 0;
135 kfree(cluster_hotplug_mask);
136 }
137
138 cluster_hotplug_mask = kzalloc_node(sizeof(*cluster_hotplug_mask),
139 GFP_KERNEL, node);
140 if (!cluster_hotplug_mask)
141 return -ENOMEM;
142 cluster_hotplug_mask->node = node;
143 return 0;
144}
145
146static int x2apic_prepare_cpu(unsigned int cpu)
147{
148 if (alloc_clustermask(cpu, cpu_to_node(cpu)) < 0)
149 return -ENOMEM;
150 if (!zalloc_cpumask_var(&per_cpu(ipi_mask, cpu), GFP_KERNEL))
151 return -ENOMEM;
152 return 0;
153}
154
155static int x2apic_dead_cpu(unsigned int dead_cpu)
156{
157 struct cluster_mask *cmsk = per_cpu(cluster_masks, dead_cpu);
158
159 if (cmsk)
160 cpumask_clear_cpu(dead_cpu, &cmsk->mask);
161 free_cpumask_var(per_cpu(ipi_mask, dead_cpu));
162 return 0;
163}
164
165static int x2apic_cluster_probe(void)
166{
167 if (!x2apic_mode)
168 return 0;
169
170 if (cpuhp_setup_state(CPUHP_X2APIC_PREPARE, "x86/x2apic:prepare",
171 x2apic_prepare_cpu, x2apic_dead_cpu) < 0) {
172 pr_err("Failed to register X2APIC_PREPARE\n");
173 return 0;
174 }
175 init_x2apic_ldr();
176 return 1;
177}
178
179static struct apic apic_x2apic_cluster __ro_after_init = {
180
181 .name = "cluster x2apic",
182 .probe = x2apic_cluster_probe,
183 .acpi_madt_oem_check = x2apic_acpi_madt_oem_check,
184 .apic_id_valid = x2apic_apic_id_valid,
185 .apic_id_registered = x2apic_apic_id_registered,
186
187 .irq_delivery_mode = dest_Fixed,
188 .irq_dest_mode = 1, /* logical */
189
190 .disable_esr = 0,
191 .dest_logical = APIC_DEST_LOGICAL,
192 .check_apicid_used = NULL,
193
194 .init_apic_ldr = init_x2apic_ldr,
195
196 .ioapic_phys_id_map = NULL,
197 .setup_apic_routing = NULL,
198 .cpu_present_to_apicid = default_cpu_present_to_apicid,
199 .apicid_to_cpu_present = NULL,
200 .check_phys_apicid_present = default_check_phys_apicid_present,
201 .phys_pkg_id = x2apic_phys_pkg_id,
202
203 .get_apic_id = x2apic_get_apic_id,
204 .set_apic_id = x2apic_set_apic_id,
205
206 .calc_dest_apicid = x2apic_calc_apicid,
207
208 .send_IPI = x2apic_send_IPI,
209 .send_IPI_mask = x2apic_send_IPI_mask,
210 .send_IPI_mask_allbutself = x2apic_send_IPI_mask_allbutself,
211 .send_IPI_allbutself = x2apic_send_IPI_allbutself,
212 .send_IPI_all = x2apic_send_IPI_all,
213 .send_IPI_self = x2apic_send_IPI_self,
214
215 .inquire_remote_apic = NULL,
216
217 .read = native_apic_msr_read,
218 .write = native_apic_msr_write,
219 .eoi_write = native_apic_msr_eoi_write,
220 .icr_read = native_x2apic_icr_read,
221 .icr_write = native_x2apic_icr_write,
222 .wait_icr_idle = native_x2apic_wait_icr_idle,
223 .safe_wait_icr_idle = native_safe_x2apic_wait_icr_idle,
224};
225
226apic_driver(apic_x2apic_cluster);
1// SPDX-License-Identifier: GPL-2.0
2
3#include <linux/cpuhotplug.h>
4#include <linux/cpumask.h>
5#include <linux/slab.h>
6#include <linux/mm.h>
7
8#include <asm/apic.h>
9
10#include "local.h"
11
12struct cluster_mask {
13 unsigned int clusterid;
14 int node;
15 struct cpumask mask;
16};
17
18/*
19 * __x2apic_send_IPI_mask() possibly needs to read
20 * x86_cpu_to_logical_apicid for all online cpus in a sequential way.
21 * Using per cpu variable would cost one cache line per cpu.
22 */
23static u32 *x86_cpu_to_logical_apicid __read_mostly;
24
25static DEFINE_PER_CPU(cpumask_var_t, ipi_mask);
26static DEFINE_PER_CPU_READ_MOSTLY(struct cluster_mask *, cluster_masks);
27static struct cluster_mask *cluster_hotplug_mask;
28
29static int x2apic_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
30{
31 return x2apic_enabled();
32}
33
34static void x2apic_send_IPI(int cpu, int vector)
35{
36 u32 dest = x86_cpu_to_logical_apicid[cpu];
37
38 /* x2apic MSRs are special and need a special fence: */
39 weak_wrmsr_fence();
40 __x2apic_send_IPI_dest(dest, vector, APIC_DEST_LOGICAL);
41}
42
43static void
44__x2apic_send_IPI_mask(const struct cpumask *mask, int vector, int apic_dest)
45{
46 unsigned int cpu, clustercpu;
47 struct cpumask *tmpmsk;
48 unsigned long flags;
49 u32 dest;
50
51 /* x2apic MSRs are special and need a special fence: */
52 weak_wrmsr_fence();
53 local_irq_save(flags);
54
55 tmpmsk = this_cpu_cpumask_var_ptr(ipi_mask);
56 cpumask_copy(tmpmsk, mask);
57 /* If IPI should not be sent to self, clear current CPU */
58 if (apic_dest != APIC_DEST_ALLINC)
59 __cpumask_clear_cpu(smp_processor_id(), tmpmsk);
60
61 /* Collapse cpus in a cluster so a single IPI per cluster is sent */
62 for_each_cpu(cpu, tmpmsk) {
63 struct cluster_mask *cmsk = per_cpu(cluster_masks, cpu);
64
65 dest = 0;
66 for_each_cpu_and(clustercpu, tmpmsk, &cmsk->mask)
67 dest |= x86_cpu_to_logical_apicid[clustercpu];
68
69 if (!dest)
70 continue;
71
72 __x2apic_send_IPI_dest(dest, vector, APIC_DEST_LOGICAL);
73 /* Remove cluster CPUs from tmpmask */
74 cpumask_andnot(tmpmsk, tmpmsk, &cmsk->mask);
75 }
76
77 local_irq_restore(flags);
78}
79
80static void x2apic_send_IPI_mask(const struct cpumask *mask, int vector)
81{
82 __x2apic_send_IPI_mask(mask, vector, APIC_DEST_ALLINC);
83}
84
85static void
86x2apic_send_IPI_mask_allbutself(const struct cpumask *mask, int vector)
87{
88 __x2apic_send_IPI_mask(mask, vector, APIC_DEST_ALLBUT);
89}
90
91static void x2apic_send_IPI_allbutself(int vector)
92{
93 __x2apic_send_IPI_shorthand(vector, APIC_DEST_ALLBUT);
94}
95
96static void x2apic_send_IPI_all(int vector)
97{
98 __x2apic_send_IPI_shorthand(vector, APIC_DEST_ALLINC);
99}
100
101static u32 x2apic_calc_apicid(unsigned int cpu)
102{
103 return x86_cpu_to_logical_apicid[cpu];
104}
105
106static void init_x2apic_ldr(void)
107{
108 struct cluster_mask *cmsk = this_cpu_read(cluster_masks);
109 u32 cluster, apicid = apic_read(APIC_LDR);
110 unsigned int cpu;
111
112 x86_cpu_to_logical_apicid[smp_processor_id()] = apicid;
113
114 if (cmsk)
115 goto update;
116
117 cluster = apicid >> 16;
118 for_each_online_cpu(cpu) {
119 cmsk = per_cpu(cluster_masks, cpu);
120 /* Matching cluster found. Link and update it. */
121 if (cmsk && cmsk->clusterid == cluster)
122 goto update;
123 }
124 cmsk = cluster_hotplug_mask;
125 cmsk->clusterid = cluster;
126 cluster_hotplug_mask = NULL;
127update:
128 this_cpu_write(cluster_masks, cmsk);
129 cpumask_set_cpu(smp_processor_id(), &cmsk->mask);
130}
131
132static int alloc_clustermask(unsigned int cpu, int node)
133{
134 if (per_cpu(cluster_masks, cpu))
135 return 0;
136 /*
137 * If a hotplug spare mask exists, check whether it's on the right
138 * node. If not, free it and allocate a new one.
139 */
140 if (cluster_hotplug_mask) {
141 if (cluster_hotplug_mask->node == node)
142 return 0;
143 kfree(cluster_hotplug_mask);
144 }
145
146 cluster_hotplug_mask = kzalloc_node(sizeof(*cluster_hotplug_mask),
147 GFP_KERNEL, node);
148 if (!cluster_hotplug_mask)
149 return -ENOMEM;
150 cluster_hotplug_mask->node = node;
151 return 0;
152}
153
154static int x2apic_prepare_cpu(unsigned int cpu)
155{
156 if (alloc_clustermask(cpu, cpu_to_node(cpu)) < 0)
157 return -ENOMEM;
158 if (!zalloc_cpumask_var(&per_cpu(ipi_mask, cpu), GFP_KERNEL))
159 return -ENOMEM;
160 return 0;
161}
162
163static int x2apic_dead_cpu(unsigned int dead_cpu)
164{
165 struct cluster_mask *cmsk = per_cpu(cluster_masks, dead_cpu);
166
167 if (cmsk)
168 cpumask_clear_cpu(dead_cpu, &cmsk->mask);
169 free_cpumask_var(per_cpu(ipi_mask, dead_cpu));
170 return 0;
171}
172
173static int x2apic_cluster_probe(void)
174{
175 u32 slots;
176
177 if (!x2apic_mode)
178 return 0;
179
180 slots = max_t(u32, L1_CACHE_BYTES/sizeof(u32), nr_cpu_ids);
181 x86_cpu_to_logical_apicid = kcalloc(slots, sizeof(u32), GFP_KERNEL);
182 if (!x86_cpu_to_logical_apicid)
183 return 0;
184
185 if (cpuhp_setup_state(CPUHP_X2APIC_PREPARE, "x86/x2apic:prepare",
186 x2apic_prepare_cpu, x2apic_dead_cpu) < 0) {
187 pr_err("Failed to register X2APIC_PREPARE\n");
188 kfree(x86_cpu_to_logical_apicid);
189 x86_cpu_to_logical_apicid = NULL;
190 return 0;
191 }
192 init_x2apic_ldr();
193 return 1;
194}
195
196static struct apic apic_x2apic_cluster __ro_after_init = {
197
198 .name = "cluster x2apic",
199 .probe = x2apic_cluster_probe,
200 .acpi_madt_oem_check = x2apic_acpi_madt_oem_check,
201 .apic_id_valid = x2apic_apic_id_valid,
202 .apic_id_registered = x2apic_apic_id_registered,
203
204 .delivery_mode = APIC_DELIVERY_MODE_FIXED,
205 .dest_mode_logical = true,
206
207 .disable_esr = 0,
208
209 .check_apicid_used = NULL,
210 .init_apic_ldr = init_x2apic_ldr,
211 .ioapic_phys_id_map = NULL,
212 .setup_apic_routing = NULL,
213 .cpu_present_to_apicid = default_cpu_present_to_apicid,
214 .apicid_to_cpu_present = NULL,
215 .check_phys_apicid_present = default_check_phys_apicid_present,
216 .phys_pkg_id = x2apic_phys_pkg_id,
217
218 .get_apic_id = x2apic_get_apic_id,
219 .set_apic_id = x2apic_set_apic_id,
220
221 .calc_dest_apicid = x2apic_calc_apicid,
222
223 .send_IPI = x2apic_send_IPI,
224 .send_IPI_mask = x2apic_send_IPI_mask,
225 .send_IPI_mask_allbutself = x2apic_send_IPI_mask_allbutself,
226 .send_IPI_allbutself = x2apic_send_IPI_allbutself,
227 .send_IPI_all = x2apic_send_IPI_all,
228 .send_IPI_self = x2apic_send_IPI_self,
229
230 .inquire_remote_apic = NULL,
231
232 .read = native_apic_msr_read,
233 .write = native_apic_msr_write,
234 .eoi_write = native_apic_msr_eoi_write,
235 .icr_read = native_x2apic_icr_read,
236 .icr_write = native_x2apic_icr_write,
237 .wait_icr_idle = native_x2apic_wait_icr_idle,
238 .safe_wait_icr_idle = native_safe_x2apic_wait_icr_idle,
239};
240
241apic_driver(apic_x2apic_cluster);