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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Default generic APIC driver. This handles up to 8 CPUs.
4 *
5 * Copyright 2003 Andi Kleen, SuSE Labs.
6 *
7 * Generic x86 APIC driver probe layer.
8 */
9#include <linux/export.h>
10#include <linux/errno.h>
11#include <linux/smp.h>
12
13#include <xen/xen.h>
14
15#include <asm/io_apic.h>
16#include <asm/apic.h>
17#include <asm/acpi.h>
18
19#include "local.h"
20
21static u32 default_get_apic_id(u32 x)
22{
23 unsigned int ver = GET_APIC_VERSION(apic_read(APIC_LVR));
24
25 if (APIC_XAPIC(ver) || boot_cpu_has(X86_FEATURE_EXTD_APICID))
26 return (x >> 24) & 0xFF;
27 else
28 return (x >> 24) & 0x0F;
29}
30
31/* should be called last. */
32static int probe_default(void)
33{
34 return 1;
35}
36
37static struct apic apic_default __ro_after_init = {
38
39 .name = "default",
40 .probe = probe_default,
41
42 .dest_mode_logical = true,
43
44 .disable_esr = 0,
45
46 .init_apic_ldr = default_init_apic_ldr,
47 .cpu_present_to_apicid = default_cpu_present_to_apicid,
48
49 .max_apic_id = 0xFE,
50 .get_apic_id = default_get_apic_id,
51
52 .calc_dest_apicid = apic_flat_calc_apicid,
53
54 .send_IPI = default_send_IPI_single,
55 .send_IPI_mask = default_send_IPI_mask_logical,
56 .send_IPI_mask_allbutself = default_send_IPI_mask_allbutself_logical,
57 .send_IPI_allbutself = default_send_IPI_allbutself,
58 .send_IPI_all = default_send_IPI_all,
59 .send_IPI_self = default_send_IPI_self,
60
61 .read = native_apic_mem_read,
62 .write = native_apic_mem_write,
63 .eoi = native_apic_mem_eoi,
64 .icr_read = native_apic_icr_read,
65 .icr_write = native_apic_icr_write,
66 .wait_icr_idle = apic_mem_wait_icr_idle,
67 .safe_wait_icr_idle = apic_mem_wait_icr_idle_timeout,
68};
69
70apic_driver(apic_default);
71
72struct apic *apic __ro_after_init = &apic_default;
73EXPORT_SYMBOL_GPL(apic);
74
75static int cmdline_apic __initdata;
76static int __init parse_apic(char *arg)
77{
78 struct apic **drv;
79
80 if (!arg)
81 return -EINVAL;
82
83 for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) {
84 if (!strcmp((*drv)->name, arg)) {
85 apic_install_driver(*drv);
86 cmdline_apic = 1;
87 return 0;
88 }
89 }
90
91 /* Parsed again by __setup for debug/verbose */
92 return 0;
93}
94early_param("apic", parse_apic);
95
96void __init x86_32_probe_bigsmp_early(void)
97{
98 if (nr_cpu_ids <= 8 || xen_pv_domain())
99 return;
100
101 if (IS_ENABLED(CONFIG_X86_BIGSMP)) {
102 switch (boot_cpu_data.x86_vendor) {
103 case X86_VENDOR_INTEL:
104 if (!APIC_XAPIC(boot_cpu_apic_version))
105 break;
106 /* P4 and above */
107 fallthrough;
108 case X86_VENDOR_HYGON:
109 case X86_VENDOR_AMD:
110 if (apic_bigsmp_possible(cmdline_apic))
111 return;
112 break;
113 }
114 }
115 pr_info("Limiting to 8 possible CPUs\n");
116 set_nr_cpu_ids(8);
117}
118
119void __init x86_32_install_bigsmp(void)
120{
121 if (nr_cpu_ids > 8 && !xen_pv_domain())
122 apic_bigsmp_force();
123}
124
125void __init x86_32_probe_apic(void)
126{
127 if (!cmdline_apic) {
128 struct apic **drv;
129
130 for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) {
131 if ((*drv)->probe()) {
132 apic_install_driver(*drv);
133 break;
134 }
135 }
136 /* Not visible without early console */
137 if (drv == __apicdrivers_end)
138 panic("Didn't find an APIC driver");
139 }
140}
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Default generic APIC driver. This handles up to 8 CPUs.
4 *
5 * Copyright 2003 Andi Kleen, SuSE Labs.
6 *
7 * Generic x86 APIC driver probe layer.
8 */
9#include <linux/export.h>
10#include <linux/errno.h>
11#include <linux/smp.h>
12
13#include <asm/io_apic.h>
14#include <asm/apic.h>
15#include <asm/acpi.h>
16
17#include "local.h"
18
19static int default_x86_32_early_logical_apicid(int cpu)
20{
21 return 1 << cpu;
22}
23
24static void setup_apic_flat_routing(void)
25{
26#ifdef CONFIG_X86_IO_APIC
27 printk(KERN_INFO
28 "Enabling APIC mode: Flat. Using %d I/O APICs\n",
29 nr_ioapics);
30#endif
31}
32
33static int default_apic_id_registered(void)
34{
35 return physid_isset(read_apic_id(), phys_cpu_present_map);
36}
37
38/*
39 * Set up the logical destination ID. Intel recommends to set DFR, LDR and
40 * TPR before enabling an APIC. See e.g. "AP-388 82489DX User's Manual"
41 * (Intel document number 292116).
42 */
43static void default_init_apic_ldr(void)
44{
45 unsigned long val;
46
47 apic_write(APIC_DFR, APIC_DFR_VALUE);
48 val = apic_read(APIC_LDR) & ~APIC_LDR_MASK;
49 val |= SET_APIC_LOGICAL_ID(1UL << smp_processor_id());
50 apic_write(APIC_LDR, val);
51}
52
53static int default_phys_pkg_id(int cpuid_apic, int index_msb)
54{
55 return cpuid_apic >> index_msb;
56}
57
58/* should be called last. */
59static int probe_default(void)
60{
61 return 1;
62}
63
64static struct apic apic_default __ro_after_init = {
65
66 .name = "default",
67 .probe = probe_default,
68 .acpi_madt_oem_check = NULL,
69 .apic_id_valid = default_apic_id_valid,
70 .apic_id_registered = default_apic_id_registered,
71
72 .irq_delivery_mode = dest_Fixed,
73 /* logical delivery broadcast to all CPUs: */
74 .irq_dest_mode = 1,
75
76 .disable_esr = 0,
77 .dest_logical = APIC_DEST_LOGICAL,
78 .check_apicid_used = default_check_apicid_used,
79
80 .init_apic_ldr = default_init_apic_ldr,
81
82 .ioapic_phys_id_map = default_ioapic_phys_id_map,
83 .setup_apic_routing = setup_apic_flat_routing,
84 .cpu_present_to_apicid = default_cpu_present_to_apicid,
85 .apicid_to_cpu_present = physid_set_mask_of_physid,
86 .check_phys_apicid_present = default_check_phys_apicid_present,
87 .phys_pkg_id = default_phys_pkg_id,
88
89 .get_apic_id = default_get_apic_id,
90 .set_apic_id = NULL,
91
92 .calc_dest_apicid = apic_flat_calc_apicid,
93
94 .send_IPI = default_send_IPI_single,
95 .send_IPI_mask = default_send_IPI_mask_logical,
96 .send_IPI_mask_allbutself = default_send_IPI_mask_allbutself_logical,
97 .send_IPI_allbutself = default_send_IPI_allbutself,
98 .send_IPI_all = default_send_IPI_all,
99 .send_IPI_self = default_send_IPI_self,
100
101 .inquire_remote_apic = default_inquire_remote_apic,
102
103 .read = native_apic_mem_read,
104 .write = native_apic_mem_write,
105 .eoi_write = native_apic_mem_write,
106 .icr_read = native_apic_icr_read,
107 .icr_write = native_apic_icr_write,
108 .wait_icr_idle = native_apic_wait_icr_idle,
109 .safe_wait_icr_idle = native_safe_apic_wait_icr_idle,
110
111 .x86_32_early_logical_apicid = default_x86_32_early_logical_apicid,
112};
113
114apic_driver(apic_default);
115
116struct apic *apic __ro_after_init = &apic_default;
117EXPORT_SYMBOL_GPL(apic);
118
119static int cmdline_apic __initdata;
120static int __init parse_apic(char *arg)
121{
122 struct apic **drv;
123
124 if (!arg)
125 return -EINVAL;
126
127 for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) {
128 if (!strcmp((*drv)->name, arg)) {
129 apic = *drv;
130 cmdline_apic = 1;
131 return 0;
132 }
133 }
134
135 /* Parsed again by __setup for debug/verbose */
136 return 0;
137}
138early_param("apic", parse_apic);
139
140void __init default_setup_apic_routing(void)
141{
142 int version = boot_cpu_apic_version;
143
144 if (num_possible_cpus() > 8) {
145 switch (boot_cpu_data.x86_vendor) {
146 case X86_VENDOR_INTEL:
147 if (!APIC_XAPIC(version)) {
148 def_to_bigsmp = 0;
149 break;
150 }
151 /* P4 and above */
152 fallthrough;
153 case X86_VENDOR_HYGON:
154 case X86_VENDOR_AMD:
155 def_to_bigsmp = 1;
156 }
157 }
158
159#ifdef CONFIG_X86_BIGSMP
160 /*
161 * This is used to switch to bigsmp mode when
162 * - There is no apic= option specified by the user
163 * - generic_apic_probe() has chosen apic_default as the sub_arch
164 * - we find more than 8 CPUs in acpi LAPIC listing with xAPIC support
165 */
166
167 if (!cmdline_apic && apic == &apic_default)
168 generic_bigsmp_probe();
169#endif
170
171 if (apic->setup_apic_routing)
172 apic->setup_apic_routing();
173
174 if (x86_platform.apic_post_init)
175 x86_platform.apic_post_init();
176}
177
178void __init generic_apic_probe(void)
179{
180 if (!cmdline_apic) {
181 struct apic **drv;
182
183 for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) {
184 if ((*drv)->probe()) {
185 apic = *drv;
186 break;
187 }
188 }
189 /* Not visible without early console */
190 if (drv == __apicdrivers_end)
191 panic("Didn't find an APIC driver");
192 }
193 printk(KERN_INFO "Using APIC driver %s\n", apic->name);
194}
195
196/* This function can switch the APIC even after the initial ->probe() */
197int __init default_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
198{
199 struct apic **drv;
200
201 for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) {
202 if (!(*drv)->acpi_madt_oem_check)
203 continue;
204 if (!(*drv)->acpi_madt_oem_check(oem_id, oem_table_id))
205 continue;
206
207 if (!cmdline_apic) {
208 apic = *drv;
209 printk(KERN_INFO "Switched to APIC driver `%s'.\n",
210 apic->name);
211 }
212 return 1;
213 }
214 return 0;
215}