1 /*
2 * Copyright 2004 James Cleverdon, IBM.
3 * Subject to the GNU Public License, v.2
4 *
5 * Flat APIC subarch code.
6 *
7 * Hacked for x86-64 by James Cleverdon from i386 architecture code by
8 * Martin Bligh, Andi Kleen, James Bottomley, John Stultz, and
9 * James Cleverdon.
10 */
11 #include <linux/errno.h>
12 #include <linux/threads.h>
13 #include <linux/cpumask.h>
14 #include <linux/string.h>
15 #include <linux/kernel.h>
16 #include <linux/ctype.h>
17 #include <linux/hardirq.h>
18 #include <linux/export.h>
19 #include <asm/smp.h>
20 #include <asm/apic.h>
21 #include <asm/ipi.h>
22 #include <asm/jailhouse_para.h>
23
24 #include <linux/acpi.h>
25
26 static struct apic apic_physflat;
27 static struct apic apic_flat;
28
29 struct apic *apic __ro_after_init = &apic_flat;
30 EXPORT_SYMBOL_GPL(apic);
31
flat_acpi_madt_oem_check(char * oem_id,char * oem_table_id)32 static int flat_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
33 {
34 return 1;
35 }
36
37 /*
38 * Set up the logical destination ID.
39 *
40 * Intel recommends to set DFR, LDR and TPR before enabling
41 * an APIC. See e.g. "AP-388 82489DX User's Manual" (Intel
42 * document number 292116). So here it goes...
43 */
flat_init_apic_ldr(void)44 void flat_init_apic_ldr(void)
45 {
46 unsigned long val;
47 unsigned long num, id;
48
49 num = smp_processor_id();
50 id = 1UL << num;
51 apic_write(APIC_DFR, APIC_DFR_FLAT);
52 val = apic_read(APIC_LDR) & ~APIC_LDR_MASK;
53 val |= SET_APIC_LOGICAL_ID(id);
54 apic_write(APIC_LDR, val);
55 }
56
_flat_send_IPI_mask(unsigned long mask,int vector)57 static void _flat_send_IPI_mask(unsigned long mask, int vector)
58 {
59 unsigned long flags;
60
61 local_irq_save(flags);
62 __default_send_IPI_dest_field(mask, vector, apic->dest_logical);
63 local_irq_restore(flags);
64 }
65
flat_send_IPI_mask(const struct cpumask * cpumask,int vector)66 static void flat_send_IPI_mask(const struct cpumask *cpumask, int vector)
67 {
68 unsigned long mask = cpumask_bits(cpumask)[0];
69
70 _flat_send_IPI_mask(mask, vector);
71 }
72
73 static void
flat_send_IPI_mask_allbutself(const struct cpumask * cpumask,int vector)74 flat_send_IPI_mask_allbutself(const struct cpumask *cpumask, int vector)
75 {
76 unsigned long mask = cpumask_bits(cpumask)[0];
77 int cpu = smp_processor_id();
78
79 if (cpu < BITS_PER_LONG)
80 clear_bit(cpu, &mask);
81
82 _flat_send_IPI_mask(mask, vector);
83 }
84
flat_send_IPI_allbutself(int vector)85 static void flat_send_IPI_allbutself(int vector)
86 {
87 int cpu = smp_processor_id();
88
89 if (IS_ENABLED(CONFIG_HOTPLUG_CPU) || vector == NMI_VECTOR) {
90 if (!cpumask_equal(cpu_online_mask, cpumask_of(cpu))) {
91 unsigned long mask = cpumask_bits(cpu_online_mask)[0];
92
93 if (cpu < BITS_PER_LONG)
94 clear_bit(cpu, &mask);
95
96 _flat_send_IPI_mask(mask, vector);
97 }
98 } else if (num_online_cpus() > 1) {
99 __default_send_IPI_shortcut(APIC_DEST_ALLBUT,
100 vector, apic->dest_logical);
101 }
102 }
103
flat_send_IPI_all(int vector)104 static void flat_send_IPI_all(int vector)
105 {
106 if (vector == NMI_VECTOR) {
107 flat_send_IPI_mask(cpu_online_mask, vector);
108 } else {
109 __default_send_IPI_shortcut(APIC_DEST_ALLINC,
110 vector, apic->dest_logical);
111 }
112 }
113
flat_get_apic_id(unsigned long x)114 static unsigned int flat_get_apic_id(unsigned long x)
115 {
116 return (x >> 24) & 0xFF;
117 }
118
set_apic_id(unsigned int id)119 static u32 set_apic_id(unsigned int id)
120 {
121 return (id & 0xFF) << 24;
122 }
123
read_xapic_id(void)124 static unsigned int read_xapic_id(void)
125 {
126 return flat_get_apic_id(apic_read(APIC_ID));
127 }
128
flat_apic_id_registered(void)129 static int flat_apic_id_registered(void)
130 {
131 return physid_isset(read_xapic_id(), phys_cpu_present_map);
132 }
133
flat_phys_pkg_id(int initial_apic_id,int index_msb)134 static int flat_phys_pkg_id(int initial_apic_id, int index_msb)
135 {
136 return initial_apic_id >> index_msb;
137 }
138
flat_probe(void)139 static int flat_probe(void)
140 {
141 return 1;
142 }
143
144 static struct apic apic_flat __ro_after_init = {
145 .name = "flat",
146 .probe = flat_probe,
147 .acpi_madt_oem_check = flat_acpi_madt_oem_check,
148 .apic_id_valid = default_apic_id_valid,
149 .apic_id_registered = flat_apic_id_registered,
150
151 .irq_delivery_mode = dest_Fixed,
152 .irq_dest_mode = 1, /* logical */
153
154 .disable_esr = 0,
155 .dest_logical = APIC_DEST_LOGICAL,
156 .check_apicid_used = NULL,
157
158 .init_apic_ldr = flat_init_apic_ldr,
159
160 .ioapic_phys_id_map = NULL,
161 .setup_apic_routing = NULL,
162 .cpu_present_to_apicid = default_cpu_present_to_apicid,
163 .apicid_to_cpu_present = NULL,
164 .check_phys_apicid_present = default_check_phys_apicid_present,
165 .phys_pkg_id = flat_phys_pkg_id,
166
167 .get_apic_id = flat_get_apic_id,
168 .set_apic_id = set_apic_id,
169
170 .calc_dest_apicid = apic_flat_calc_apicid,
171
172 .send_IPI = default_send_IPI_single,
173 .send_IPI_mask = flat_send_IPI_mask,
174 .send_IPI_mask_allbutself = flat_send_IPI_mask_allbutself,
175 .send_IPI_allbutself = flat_send_IPI_allbutself,
176 .send_IPI_all = flat_send_IPI_all,
177 .send_IPI_self = apic_send_IPI_self,
178
179 .inquire_remote_apic = default_inquire_remote_apic,
180
181 .read = native_apic_mem_read,
182 .write = native_apic_mem_write,
183 .eoi_write = native_apic_mem_write,
184 .icr_read = native_apic_icr_read,
185 .icr_write = native_apic_icr_write,
186 .wait_icr_idle = native_apic_wait_icr_idle,
187 .safe_wait_icr_idle = native_safe_apic_wait_icr_idle,
188 };
189
190 /*
191 * Physflat mode is used when there are more than 8 CPUs on a system.
192 * We cannot use logical delivery in this case because the mask
193 * overflows, so use physical mode.
194 */
physflat_acpi_madt_oem_check(char * oem_id,char * oem_table_id)195 static int physflat_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
196 {
197 #ifdef CONFIG_ACPI
198 /*
199 * Quirk: some x86_64 machines can only use physical APIC mode
200 * regardless of how many processors are present (x86_64 ES7000
201 * is an example).
202 */
203 if (acpi_gbl_FADT.header.revision >= FADT2_REVISION_ID &&
204 (acpi_gbl_FADT.flags & ACPI_FADT_APIC_PHYSICAL)) {
205 printk(KERN_DEBUG "system APIC only can use physical flat");
206 return 1;
207 }
208
209 if (!strncmp(oem_id, "IBM", 3) && !strncmp(oem_table_id, "EXA", 3)) {
210 printk(KERN_DEBUG "IBM Summit detected, will use apic physical");
211 return 1;
212 }
213 #endif
214
215 return 0;
216 }
217
physflat_init_apic_ldr(void)218 static void physflat_init_apic_ldr(void)
219 {
220 /*
221 * LDR and DFR are not involved in physflat mode, rather:
222 * "In physical destination mode, the destination processor is
223 * specified by its local APIC ID [...]." (Intel SDM, 10.6.2.1)
224 */
225 }
226
physflat_send_IPI_allbutself(int vector)227 static void physflat_send_IPI_allbutself(int vector)
228 {
229 default_send_IPI_mask_allbutself_phys(cpu_online_mask, vector);
230 }
231
physflat_send_IPI_all(int vector)232 static void physflat_send_IPI_all(int vector)
233 {
234 default_send_IPI_mask_sequence_phys(cpu_online_mask, vector);
235 }
236
physflat_probe(void)237 static int physflat_probe(void)
238 {
239 if (apic == &apic_physflat || num_possible_cpus() > 8 ||
240 jailhouse_paravirt())
241 return 1;
242
243 return 0;
244 }
245
246 static struct apic apic_physflat __ro_after_init = {
247
248 .name = "physical flat",
249 .probe = physflat_probe,
250 .acpi_madt_oem_check = physflat_acpi_madt_oem_check,
251 .apic_id_valid = default_apic_id_valid,
252 .apic_id_registered = flat_apic_id_registered,
253
254 .irq_delivery_mode = dest_Fixed,
255 .irq_dest_mode = 0, /* physical */
256
257 .disable_esr = 0,
258 .dest_logical = 0,
259 .check_apicid_used = NULL,
260
261 .init_apic_ldr = physflat_init_apic_ldr,
262
263 .ioapic_phys_id_map = NULL,
264 .setup_apic_routing = NULL,
265 .cpu_present_to_apicid = default_cpu_present_to_apicid,
266 .apicid_to_cpu_present = NULL,
267 .check_phys_apicid_present = default_check_phys_apicid_present,
268 .phys_pkg_id = flat_phys_pkg_id,
269
270 .get_apic_id = flat_get_apic_id,
271 .set_apic_id = set_apic_id,
272
273 .calc_dest_apicid = apic_default_calc_apicid,
274
275 .send_IPI = default_send_IPI_single_phys,
276 .send_IPI_mask = default_send_IPI_mask_sequence_phys,
277 .send_IPI_mask_allbutself = default_send_IPI_mask_allbutself_phys,
278 .send_IPI_allbutself = physflat_send_IPI_allbutself,
279 .send_IPI_all = physflat_send_IPI_all,
280 .send_IPI_self = apic_send_IPI_self,
281
282 .inquire_remote_apic = default_inquire_remote_apic,
283
284 .read = native_apic_mem_read,
285 .write = native_apic_mem_write,
286 .eoi_write = native_apic_mem_write,
287 .icr_read = native_apic_icr_read,
288 .icr_write = native_apic_icr_write,
289 .wait_icr_idle = native_apic_wait_icr_idle,
290 .safe_wait_icr_idle = native_safe_apic_wait_icr_idle,
291 };
292
293 /*
294 * We need to check for physflat first, so this order is important.
295 */
296 apic_drivers(apic_physflat, apic_flat);
297