Loading...
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 .delivery_mode = APIC_DELIVERY_MODE_FIXED,
73 .dest_mode_logical = true,
74
75 .disable_esr = 0,
76
77 .check_apicid_used = default_check_apicid_used,
78 .init_apic_ldr = default_init_apic_ldr,
79 .ioapic_phys_id_map = default_ioapic_phys_id_map,
80 .setup_apic_routing = setup_apic_flat_routing,
81 .cpu_present_to_apicid = default_cpu_present_to_apicid,
82 .apicid_to_cpu_present = physid_set_mask_of_physid,
83 .check_phys_apicid_present = default_check_phys_apicid_present,
84 .phys_pkg_id = default_phys_pkg_id,
85
86 .get_apic_id = default_get_apic_id,
87 .set_apic_id = NULL,
88
89 .calc_dest_apicid = apic_flat_calc_apicid,
90
91 .send_IPI = default_send_IPI_single,
92 .send_IPI_mask = default_send_IPI_mask_logical,
93 .send_IPI_mask_allbutself = default_send_IPI_mask_allbutself_logical,
94 .send_IPI_allbutself = default_send_IPI_allbutself,
95 .send_IPI_all = default_send_IPI_all,
96 .send_IPI_self = default_send_IPI_self,
97
98 .inquire_remote_apic = default_inquire_remote_apic,
99
100 .read = native_apic_mem_read,
101 .write = native_apic_mem_write,
102 .eoi_write = native_apic_mem_write,
103 .icr_read = native_apic_icr_read,
104 .icr_write = native_apic_icr_write,
105 .wait_icr_idle = native_apic_wait_icr_idle,
106 .safe_wait_icr_idle = native_safe_apic_wait_icr_idle,
107
108 .x86_32_early_logical_apicid = default_x86_32_early_logical_apicid,
109};
110
111apic_driver(apic_default);
112
113struct apic *apic __ro_after_init = &apic_default;
114EXPORT_SYMBOL_GPL(apic);
115
116static int cmdline_apic __initdata;
117static int __init parse_apic(char *arg)
118{
119 struct apic **drv;
120
121 if (!arg)
122 return -EINVAL;
123
124 for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) {
125 if (!strcmp((*drv)->name, arg)) {
126 apic = *drv;
127 cmdline_apic = 1;
128 return 0;
129 }
130 }
131
132 /* Parsed again by __setup for debug/verbose */
133 return 0;
134}
135early_param("apic", parse_apic);
136
137void __init default_setup_apic_routing(void)
138{
139 int version = boot_cpu_apic_version;
140
141 if (num_possible_cpus() > 8) {
142 switch (boot_cpu_data.x86_vendor) {
143 case X86_VENDOR_INTEL:
144 if (!APIC_XAPIC(version)) {
145 def_to_bigsmp = 0;
146 break;
147 }
148 /* P4 and above */
149 fallthrough;
150 case X86_VENDOR_HYGON:
151 case X86_VENDOR_AMD:
152 def_to_bigsmp = 1;
153 }
154 }
155
156#ifdef CONFIG_X86_BIGSMP
157 /*
158 * This is used to switch to bigsmp mode when
159 * - There is no apic= option specified by the user
160 * - generic_apic_probe() has chosen apic_default as the sub_arch
161 * - we find more than 8 CPUs in acpi LAPIC listing with xAPIC support
162 */
163
164 if (!cmdline_apic && apic == &apic_default)
165 generic_bigsmp_probe();
166#endif
167
168 if (apic->setup_apic_routing)
169 apic->setup_apic_routing();
170}
171
172void __init generic_apic_probe(void)
173{
174 if (!cmdline_apic) {
175 struct apic **drv;
176
177 for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) {
178 if ((*drv)->probe()) {
179 apic = *drv;
180 break;
181 }
182 }
183 /* Not visible without early console */
184 if (drv == __apicdrivers_end)
185 panic("Didn't find an APIC driver");
186 }
187 printk(KERN_INFO "Using APIC driver %s\n", apic->name);
188}
189
190/* This function can switch the APIC even after the initial ->probe() */
191int __init default_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
192{
193 struct apic **drv;
194
195 for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) {
196 if (!(*drv)->acpi_madt_oem_check)
197 continue;
198 if (!(*drv)->acpi_madt_oem_check(oem_id, oem_table_id))
199 continue;
200
201 if (!cmdline_apic) {
202 apic = *drv;
203 printk(KERN_INFO "Switched to APIC driver `%s'.\n",
204 apic->name);
205 }
206 return 1;
207 }
208 return 0;
209}