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 static u32 x2apic_max_apicid __ro_after_init;
12 
x2apic_set_max_apicid(u32 apicid)13 void __init x2apic_set_max_apicid(u32 apicid)
14 {
15 	x2apic_max_apicid = apicid;
16 }
17 
set_x2apic_phys_mode(char * arg)18 static int __init set_x2apic_phys_mode(char *arg)
19 {
20 	x2apic_phys = 1;
21 	return 0;
22 }
23 early_param("x2apic_phys", set_x2apic_phys_mode);
24 
x2apic_fadt_phys(void)25 static bool x2apic_fadt_phys(void)
26 {
27 #ifdef CONFIG_ACPI
28 	if ((acpi_gbl_FADT.header.revision >= FADT2_REVISION_ID) &&
29 		(acpi_gbl_FADT.flags & ACPI_FADT_APIC_PHYSICAL)) {
30 		printk(KERN_DEBUG "System requires x2apic physical mode\n");
31 		return true;
32 	}
33 #endif
34 	return false;
35 }
36 
x2apic_acpi_madt_oem_check(char * oem_id,char * oem_table_id)37 static int x2apic_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
38 {
39 	return x2apic_enabled() && (x2apic_phys || x2apic_fadt_phys());
40 }
41 
x2apic_send_IPI(int cpu,int vector)42 static void x2apic_send_IPI(int cpu, int vector)
43 {
44 	u32 dest = per_cpu(x86_cpu_to_apicid, cpu);
45 
46 	/* x2apic MSRs are special and need a special fence: */
47 	weak_wrmsr_fence();
48 	__x2apic_send_IPI_dest(dest, vector, APIC_DEST_PHYSICAL);
49 }
50 
51 static void
__x2apic_send_IPI_mask(const struct cpumask * mask,int vector,int apic_dest)52 __x2apic_send_IPI_mask(const struct cpumask *mask, int vector, int apic_dest)
53 {
54 	unsigned long query_cpu;
55 	unsigned long this_cpu;
56 	unsigned long flags;
57 
58 	/* x2apic MSRs are special and need a special fence: */
59 	weak_wrmsr_fence();
60 
61 	local_irq_save(flags);
62 
63 	this_cpu = smp_processor_id();
64 	for_each_cpu(query_cpu, mask) {
65 		if (apic_dest == APIC_DEST_ALLBUT && this_cpu == query_cpu)
66 			continue;
67 		__x2apic_send_IPI_dest(per_cpu(x86_cpu_to_apicid, query_cpu),
68 				       vector, APIC_DEST_PHYSICAL);
69 	}
70 	local_irq_restore(flags);
71 }
72 
x2apic_send_IPI_mask(const struct cpumask * mask,int vector)73 static void x2apic_send_IPI_mask(const struct cpumask *mask, int vector)
74 {
75 	__x2apic_send_IPI_mask(mask, vector, APIC_DEST_ALLINC);
76 }
77 
78 static void
x2apic_send_IPI_mask_allbutself(const struct cpumask * mask,int vector)79  x2apic_send_IPI_mask_allbutself(const struct cpumask *mask, int vector)
80 {
81 	__x2apic_send_IPI_mask(mask, vector, APIC_DEST_ALLBUT);
82 }
83 
x2apic_send_IPI_allbutself(int vector)84 static void x2apic_send_IPI_allbutself(int vector)
85 {
86 	__x2apic_send_IPI_shorthand(vector, APIC_DEST_ALLBUT);
87 }
88 
x2apic_send_IPI_all(int vector)89 static void x2apic_send_IPI_all(int vector)
90 {
91 	__x2apic_send_IPI_shorthand(vector, APIC_DEST_ALLINC);
92 }
93 
init_x2apic_ldr(void)94 static void init_x2apic_ldr(void)
95 {
96 }
97 
x2apic_phys_probe(void)98 static int x2apic_phys_probe(void)
99 {
100 	if (x2apic_mode && (x2apic_phys || x2apic_fadt_phys()))
101 		return 1;
102 
103 	return apic == &apic_x2apic_phys;
104 }
105 
106 /* Common x2apic functions, also used by x2apic_cluster */
x2apic_apic_id_valid(u32 apicid)107 int x2apic_apic_id_valid(u32 apicid)
108 {
109 	if (x2apic_max_apicid && apicid > x2apic_max_apicid)
110 		return 0;
111 
112 	return 1;
113 }
114 
x2apic_apic_id_registered(void)115 int x2apic_apic_id_registered(void)
116 {
117 	return 1;
118 }
119 
__x2apic_send_IPI_dest(unsigned int apicid,int vector,unsigned int dest)120 void __x2apic_send_IPI_dest(unsigned int apicid, int vector, unsigned int dest)
121 {
122 	unsigned long cfg = __prepare_ICR(0, vector, dest);
123 	native_x2apic_icr_write(cfg, apicid);
124 }
125 
__x2apic_send_IPI_shorthand(int vector,u32 which)126 void __x2apic_send_IPI_shorthand(int vector, u32 which)
127 {
128 	unsigned long cfg = __prepare_ICR(which, vector, 0);
129 
130 	/* x2apic MSRs are special and need a special fence: */
131 	weak_wrmsr_fence();
132 	native_x2apic_icr_write(cfg, 0);
133 }
134 
x2apic_get_apic_id(unsigned long id)135 unsigned int x2apic_get_apic_id(unsigned long id)
136 {
137 	return id;
138 }
139 
x2apic_set_apic_id(unsigned int id)140 u32 x2apic_set_apic_id(unsigned int id)
141 {
142 	return id;
143 }
144 
x2apic_phys_pkg_id(int initial_apicid,int index_msb)145 int x2apic_phys_pkg_id(int initial_apicid, int index_msb)
146 {
147 	return initial_apicid >> index_msb;
148 }
149 
x2apic_send_IPI_self(int vector)150 void x2apic_send_IPI_self(int vector)
151 {
152 	apic_write(APIC_SELF_IPI, vector);
153 }
154 
155 static struct apic apic_x2apic_phys __ro_after_init = {
156 
157 	.name				= "physical x2apic",
158 	.probe				= x2apic_phys_probe,
159 	.acpi_madt_oem_check		= x2apic_acpi_madt_oem_check,
160 	.apic_id_valid			= x2apic_apic_id_valid,
161 	.apic_id_registered		= x2apic_apic_id_registered,
162 
163 	.delivery_mode			= APIC_DELIVERY_MODE_FIXED,
164 	.dest_mode_logical		= false,
165 
166 	.disable_esr			= 0,
167 
168 	.check_apicid_used		= NULL,
169 	.init_apic_ldr			= init_x2apic_ldr,
170 	.ioapic_phys_id_map		= NULL,
171 	.setup_apic_routing		= NULL,
172 	.cpu_present_to_apicid		= default_cpu_present_to_apicid,
173 	.apicid_to_cpu_present		= NULL,
174 	.check_phys_apicid_present	= default_check_phys_apicid_present,
175 	.phys_pkg_id			= x2apic_phys_pkg_id,
176 
177 	.get_apic_id			= x2apic_get_apic_id,
178 	.set_apic_id			= x2apic_set_apic_id,
179 
180 	.calc_dest_apicid		= apic_default_calc_apicid,
181 
182 	.send_IPI			= x2apic_send_IPI,
183 	.send_IPI_mask			= x2apic_send_IPI_mask,
184 	.send_IPI_mask_allbutself	= x2apic_send_IPI_mask_allbutself,
185 	.send_IPI_allbutself		= x2apic_send_IPI_allbutself,
186 	.send_IPI_all			= x2apic_send_IPI_all,
187 	.send_IPI_self			= x2apic_send_IPI_self,
188 
189 	.inquire_remote_apic		= NULL,
190 
191 	.read				= native_apic_msr_read,
192 	.write				= native_apic_msr_write,
193 	.eoi_write			= native_apic_msr_eoi_write,
194 	.icr_read			= native_x2apic_icr_read,
195 	.icr_write			= native_x2apic_icr_write,
196 	.wait_icr_idle			= native_x2apic_wait_icr_idle,
197 	.safe_wait_icr_idle		= native_safe_x2apic_wait_icr_idle,
198 };
199 
200 apic_driver(apic_x2apic_phys);
201