1 // SPDX-License-Identifier: GPL-2.0
2
3 #include <linux/cpumask.h>
4 #include <linux/acpi.h>
5
6 #include "local.h"
7
8 int x2apic_phys;
9
10 static struct apic apic_x2apic_phys;
11 u32 x2apic_max_apicid __ro_after_init = UINT_MAX;
12
13 void __init x2apic_set_max_apicid(u32 apicid)
14 {
15 x2apic_max_apicid = apicid;
16 if (apic->x2apic_set_max_apicid)
17 apic->max_apic_id = apicid;
18 }
19
20 static int __init set_x2apic_phys_mode(char *arg)
21 {
22 x2apic_phys = 1;
23 return 0;
24 }
25 early_param("x2apic_phys", set_x2apic_phys_mode);
26
27 static bool x2apic_fadt_phys(void)
28 {
29 #ifdef CONFIG_ACPI
30 if ((acpi_gbl_FADT.header.revision >= FADT2_REVISION_ID) &&
31 (acpi_gbl_FADT.flags & ACPI_FADT_APIC_PHYSICAL)) {
32 printk(KERN_DEBUG "System requires x2apic physical mode\n");
33 return true;
34 }
35 #endif
36 return false;
37 }
38
39 static int x2apic_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
40 {
41 return x2apic_enabled() && (x2apic_phys || x2apic_fadt_phys());
42 }
43
44 static void x2apic_send_IPI(int cpu, int vector)
45 {
46 u32 dest = per_cpu(x86_cpu_to_apicid, cpu);
47
48 /* x2apic MSRs are special and need a special fence: */
49 weak_wrmsr_fence();
50 __x2apic_send_IPI_dest(dest, vector, APIC_DEST_PHYSICAL);
51 }
52
53 static void
54 __x2apic_send_IPI_mask(const struct cpumask *mask, int vector, int apic_dest)
55 {
56 unsigned long query_cpu;
57 unsigned long this_cpu;
58 unsigned long flags;
59
60 /* x2apic MSRs are special and need a special fence: */
61 weak_wrmsr_fence();
62
63 local_irq_save(flags);
64
65 this_cpu = smp_processor_id();
66 for_each_cpu(query_cpu, mask) {
67 if (apic_dest == APIC_DEST_ALLBUT && this_cpu == query_cpu)
68 continue;
69 __x2apic_send_IPI_dest(per_cpu(x86_cpu_to_apicid, query_cpu),
70 vector, APIC_DEST_PHYSICAL);
71 }
72 local_irq_restore(flags);
73 }
74
75 static void x2apic_send_IPI_mask(const struct cpumask *mask, int vector)
76 {
77 __x2apic_send_IPI_mask(mask, vector, APIC_DEST_ALLINC);
78 }
79
80 static void
81 x2apic_send_IPI_mask_allbutself(const struct cpumask *mask, int vector)
82 {
83 __x2apic_send_IPI_mask(mask, vector, APIC_DEST_ALLBUT);
84 }
85
86 static void __x2apic_send_IPI_shorthand(int vector, u32 which)
87 {
88 unsigned long cfg = __prepare_ICR(which, vector, 0);
89
90 /* x2apic MSRs are special and need a special fence: */
91 weak_wrmsr_fence();
92 native_x2apic_icr_write(cfg, 0);
93 }
94
95 void x2apic_send_IPI_allbutself(int vector)
96 {
97 __x2apic_send_IPI_shorthand(vector, APIC_DEST_ALLBUT);
98 }
99
100 void x2apic_send_IPI_all(int vector)
101 {
102 __x2apic_send_IPI_shorthand(vector, APIC_DEST_ALLINC);
103 }
104
105 void x2apic_send_IPI_self(int vector)
106 {
107 apic_write(APIC_SELF_IPI, vector);
108 }
109
110 void __x2apic_send_IPI_dest(unsigned int apicid, int vector, unsigned int dest)
111 {
112 unsigned long cfg = __prepare_ICR(0, vector, dest);
113 native_x2apic_icr_write(cfg, apicid);
114 }
115
116 static int x2apic_phys_probe(void)
117 {
118 if (!x2apic_mode)
119 return 0;
120
121 if (x2apic_phys || x2apic_fadt_phys())
122 return 1;
123
124 return apic == &apic_x2apic_phys;
125 }
126
127 u32 x2apic_get_apic_id(u32 id)
128 {
129 return id;
130 }
131
132 static struct apic apic_x2apic_phys __ro_after_init = {
133
134 .name = "physical x2apic",
135 .probe = x2apic_phys_probe,
136 .acpi_madt_oem_check = x2apic_acpi_madt_oem_check,
137
138 .dest_mode_logical = false,
139
140 .disable_esr = 0,
141
142 .cpu_present_to_apicid = default_cpu_present_to_apicid,
143
144 .max_apic_id = UINT_MAX,
145 .x2apic_set_max_apicid = true,
146 .get_apic_id = x2apic_get_apic_id,
147
148 .calc_dest_apicid = apic_default_calc_apicid,
149
150 .send_IPI = x2apic_send_IPI,
151 .send_IPI_mask = x2apic_send_IPI_mask,
152 .send_IPI_mask_allbutself = x2apic_send_IPI_mask_allbutself,
153 .send_IPI_allbutself = x2apic_send_IPI_allbutself,
154 .send_IPI_all = x2apic_send_IPI_all,
155 .send_IPI_self = x2apic_send_IPI_self,
156 .nmi_to_offline_cpu = true,
157
158 .read = native_apic_msr_read,
159 .write = native_apic_msr_write,
160 .eoi = native_apic_msr_eoi,
161 .icr_read = native_x2apic_icr_read,
162 .icr_write = native_x2apic_icr_write,
163 };
164
165 apic_driver(apic_x2apic_phys);
166
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