arch/x86/kernel/apic/apic_flat_64.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright 2004 James Cleverdon, IBM.
   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/cpumask.h>
  12 #include <linux/export.h>
  13 #include <linux/acpi.h>
  14
  15 #include <asm/jailhouse_para.h>
  16 #include <asm/apic.h>
  17
  18 #include "local.h"
  19
  20 static struct apic apic_physflat;
  21 static struct apic apic_flat;
  22
  23 struct apic *apic __ro_after_init = &apic_flat;
  24 EXPORT_SYMBOL_GPL(apic);
  25
  26 static int flat_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
  27 {
  28         return 1;
  29 }
  30
  31 /*
  32  * Set up the logical destination ID.
  33  *
  34  * Intel recommends to set DFR, LDR and TPR before enabling
  35  * an APIC.  See e.g. "AP-388 82489DX User's Manual" (Intel
  36  * document number 292116).  So here it goes...
  37  */
  38 void flat_init_apic_ldr(void)
  39 {
  40         unsigned long val;
  41         unsigned long num, id;
  42
  43         num = smp_processor_id();
  44         id = 1UL << num;
  45         apic_write(APIC_DFR, APIC_DFR_FLAT);
  46         val = apic_read(APIC_LDR) & ~APIC_LDR_MASK;
  47         val |= SET_APIC_LOGICAL_ID(id);
  48         apic_write(APIC_LDR, val);
  49 }
  50
  51 static void _flat_send_IPI_mask(unsigned long mask, int vector)
  52 {
  53         unsigned long flags;
  54
  55         local_irq_save(flags);
  56         __default_send_IPI_dest_field(mask, vector, apic->dest_logical);
  57         local_irq_restore(flags);
  58 }
  59
  60 static void flat_send_IPI_mask(const struct cpumask *cpumask, int vector)
  61 {
  62         unsigned long mask = cpumask_bits(cpumask)[0];
  63
  64         _flat_send_IPI_mask(mask, vector);
  65 }
  66
  67 static void
  68 flat_send_IPI_mask_allbutself(const struct cpumask *cpumask, int vector)
  69 {
  70         unsigned long mask = cpumask_bits(cpumask)[0];
  71         int cpu = smp_processor_id();
  72
  73         if (cpu < BITS_PER_LONG)
  74                 __clear_bit(cpu, &mask);
  75
  76         _flat_send_IPI_mask(mask, vector);
  77 }
  78
  79 static void flat_send_IPI_allbutself(int vector)
  80 {
  81         int cpu = smp_processor_id();
  82
  83         if (IS_ENABLED(CONFIG_HOTPLUG_CPU) || vector == NMI_VECTOR) {
  84                 if (!cpumask_equal(cpu_online_mask, cpumask_of(cpu))) {
  85                         unsigned long mask = cpumask_bits(cpu_online_mask)[0];
  86
  87                         if (cpu < BITS_PER_LONG)
  88                                 __clear_bit(cpu, &mask);
  89
  90                         _flat_send_IPI_mask(mask, vector);
  91                 }
  92         } else if (num_online_cpus() > 1) {
  93                 __default_send_IPI_shortcut(APIC_DEST_ALLBUT, vector);
  94         }
  95 }
  96
  97 static void flat_send_IPI_all(int vector)
  98 {
  99         if (vector == NMI_VECTOR) {
 100                 flat_send_IPI_mask(cpu_online_mask, vector);
 101         } else {
 102                 __default_send_IPI_shortcut(APIC_DEST_ALLINC, vector);
 103         }
 104 }
 105
 106 static unsigned int flat_get_apic_id(unsigned long x)
 107 {
 108         return (x >> 24) & 0xFF;
 109 }
 110
 111 static u32 set_apic_id(unsigned int id)
 112 {
 113         return (id & 0xFF) << 24;
 114 }
 115
 116 static unsigned int read_xapic_id(void)
 117 {
 118         return flat_get_apic_id(apic_read(APIC_ID));
 119 }
 120
 121 static int flat_apic_id_registered(void)
 122 {
 123         return physid_isset(read_xapic_id(), phys_cpu_present_map);
 124 }
 125
 126 static int flat_phys_pkg_id(int initial_apic_id, int index_msb)
 127 {
 128         return initial_apic_id >> index_msb;
 129 }
 130
 131 static int flat_probe(void)
 132 {
 133         return 1;
 134 }
 135
 136 static struct apic apic_flat __ro_after_init = {
 137         .name                           = "flat",
 138         .probe                          = flat_probe,
 139         .acpi_madt_oem_check            = flat_acpi_madt_oem_check,
 140         .apic_id_valid                  = default_apic_id_valid,
 141         .apic_id_registered             = flat_apic_id_registered,
 142
 143         .irq_delivery_mode              = dest_Fixed,
 144         .irq_dest_mode                  = 1, /* logical */
 145
 146         .disable_esr                    = 0,
 147         .dest_logical                   = APIC_DEST_LOGICAL,
 148         .check_apicid_used              = NULL,
 149
 150         .init_apic_ldr                  = flat_init_apic_ldr,
 151
 152         .ioapic_phys_id_map             = NULL,
 153         .setup_apic_routing             = NULL,
 154         .cpu_present_to_apicid          = default_cpu_present_to_apicid,
 155         .apicid_to_cpu_present          = NULL,
 156         .check_phys_apicid_present      = default_check_phys_apicid_present,
 157         .phys_pkg_id                    = flat_phys_pkg_id,
 158
 159         .get_apic_id                    = flat_get_apic_id,
 160         .set_apic_id                    = set_apic_id,
 161
 162         .calc_dest_apicid               = apic_flat_calc_apicid,
 163
 164         .send_IPI                       = default_send_IPI_single,
 165         .send_IPI_mask                  = flat_send_IPI_mask,
 166         .send_IPI_mask_allbutself       = flat_send_IPI_mask_allbutself,
 167         .send_IPI_allbutself            = flat_send_IPI_allbutself,
 168         .send_IPI_all                   = flat_send_IPI_all,
 169         .send_IPI_self                  = apic_send_IPI_self,
 170
 171         .inquire_remote_apic            = default_inquire_remote_apic,
 172
 173         .read                           = native_apic_mem_read,
 174         .write                          = native_apic_mem_write,
 175         .eoi_write                      = native_apic_mem_write,
 176         .icr_read                       = native_apic_icr_read,
 177         .icr_write                      = native_apic_icr_write,
 178         .wait_icr_idle                  = native_apic_wait_icr_idle,
 179         .safe_wait_icr_idle             = native_safe_apic_wait_icr_idle,
 180 };
 181
 182 /*
 183  * Physflat mode is used when there are more than 8 CPUs on a system.
 184  * We cannot use logical delivery in this case because the mask
 185  * overflows, so use physical mode.
 186  */
 187 static int physflat_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
 188 {
 189 #ifdef CONFIG_ACPI
 190         /*
 191          * Quirk: some x86_64 machines can only use physical APIC mode
 192          * regardless of how many processors are present (x86_64 ES7000
 193          * is an example).
 194          */
 195         if (acpi_gbl_FADT.header.revision >= FADT2_REVISION_ID &&
 196                 (acpi_gbl_FADT.flags & ACPI_FADT_APIC_PHYSICAL)) {
 197                 printk(KERN_DEBUG "system APIC only can use physical flat");
 198                 return 1;
 199         }
 200
 201         if (!strncmp(oem_id, "IBM", 3) && !strncmp(oem_table_id, "EXA", 3)) {
 202                 printk(KERN_DEBUG "IBM Summit detected, will use apic physical");
 203                 return 1;
 204         }
 205 #endif
 206
 207         return 0;
 208 }
 209
 210 static void physflat_init_apic_ldr(void)
 211 {
 212         /*
 213          * LDR and DFR are not involved in physflat mode, rather:
 214          * "In physical destination mode, the destination processor is
 215          * specified by its local APIC ID [...]." (Intel SDM, 10.6.2.1)
 216          */
 217 }
 218
 219 static void physflat_send_IPI_allbutself(int vector)
 220 {
 221         default_send_IPI_mask_allbutself_phys(cpu_online_mask, vector);
 222 }
 223
 224 static void physflat_send_IPI_all(int vector)
 225 {
 226         default_send_IPI_mask_sequence_phys(cpu_online_mask, vector);
 227 }
 228
 229 static int physflat_probe(void)
 230 {
 231         if (apic == &apic_physflat || num_possible_cpus() > 8 ||
 232             jailhouse_paravirt())
 233                 return 1;
 234
 235         return 0;
 236 }
 237
 238 static struct apic apic_physflat __ro_after_init = {
 239
 240         .name                           = "physical flat",
 241         .probe                          = physflat_probe,
 242         .acpi_madt_oem_check            = physflat_acpi_madt_oem_check,
 243         .apic_id_valid                  = default_apic_id_valid,
 244         .apic_id_registered             = flat_apic_id_registered,
 245
 246         .irq_delivery_mode              = dest_Fixed,
 247         .irq_dest_mode                  = 0, /* physical */
 248
 249         .disable_esr                    = 0,
 250         .dest_logical                   = 0,
 251         .check_apicid_used              = NULL,
 252
 253         .init_apic_ldr                  = physflat_init_apic_ldr,
 254
 255         .ioapic_phys_id_map             = NULL,
 256         .setup_apic_routing             = NULL,
 257         .cpu_present_to_apicid          = default_cpu_present_to_apicid,
 258         .apicid_to_cpu_present          = NULL,
 259         .check_phys_apicid_present      = default_check_phys_apicid_present,
 260         .phys_pkg_id                    = flat_phys_pkg_id,
 261
 262         .get_apic_id                    = flat_get_apic_id,
 263         .set_apic_id                    = set_apic_id,
 264
 265         .calc_dest_apicid               = apic_default_calc_apicid,
 266
 267         .send_IPI                       = default_send_IPI_single_phys,
 268         .send_IPI_mask                  = default_send_IPI_mask_sequence_phys,
 269         .send_IPI_mask_allbutself       = default_send_IPI_mask_allbutself_phys,
 270         .send_IPI_allbutself            = physflat_send_IPI_allbutself,
 271         .send_IPI_all                   = physflat_send_IPI_all,
 272         .send_IPI_self                  = apic_send_IPI_self,
 273
 274         .inquire_remote_apic            = default_inquire_remote_apic,
 275
 276         .read                           = native_apic_mem_read,
 277         .write                          = native_apic_mem_write,
 278         .eoi_write                      = native_apic_mem_write,
 279         .icr_read                       = native_apic_icr_read,
 280         .icr_write                      = native_apic_icr_write,
 281         .wait_icr_idle                  = native_apic_wait_icr_idle,
 282         .safe_wait_icr_idle             = native_safe_apic_wait_icr_idle,
 283 };
 284
 285 /*
 286  * We need to check for physflat first, so this order is important.
 287  */
 288 apic_drivers(apic_physflat, apic_flat);