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 unsigned int flat_get_apic_id(unsigned long x)
  80 {
  81         return (x >> 24) & 0xFF;
  82 }
  83
  84 static u32 set_apic_id(unsigned int id)
  85 {
  86         return (id & 0xFF) << 24;
  87 }
  88
  89 static unsigned int read_xapic_id(void)
  90 {
  91         return flat_get_apic_id(apic_read(APIC_ID));
  92 }
  93
  94 static int flat_apic_id_registered(void)
  95 {
  96         return physid_isset(read_xapic_id(), phys_cpu_present_map);
  97 }
  98
  99 static int flat_phys_pkg_id(int initial_apic_id, int index_msb)
 100 {
 101         return initial_apic_id >> index_msb;
 102 }
 103
 104 static int flat_probe(void)
 105 {
 106         return 1;
 107 }
 108
 109 static struct apic apic_flat __ro_after_init = {
 110         .name                           = "flat",
 111         .probe                          = flat_probe,
 112         .acpi_madt_oem_check            = flat_acpi_madt_oem_check,
 113         .apic_id_valid                  = default_apic_id_valid,
 114         .apic_id_registered             = flat_apic_id_registered,
 115
 116         .irq_delivery_mode              = dest_Fixed,
 117         .irq_dest_mode                  = 1, /* logical */
 118
 119         .disable_esr                    = 0,
 120         .dest_logical                   = APIC_DEST_LOGICAL,
 121         .check_apicid_used              = NULL,
 122
 123         .init_apic_ldr                  = flat_init_apic_ldr,
 124
 125         .ioapic_phys_id_map             = NULL,
 126         .setup_apic_routing             = NULL,
 127         .cpu_present_to_apicid          = default_cpu_present_to_apicid,
 128         .apicid_to_cpu_present          = NULL,
 129         .check_phys_apicid_present      = default_check_phys_apicid_present,
 130         .phys_pkg_id                    = flat_phys_pkg_id,
 131
 132         .get_apic_id                    = flat_get_apic_id,
 133         .set_apic_id                    = set_apic_id,
 134
 135         .calc_dest_apicid               = apic_flat_calc_apicid,
 136
 137         .send_IPI                       = default_send_IPI_single,
 138         .send_IPI_mask                  = flat_send_IPI_mask,
 139         .send_IPI_mask_allbutself       = flat_send_IPI_mask_allbutself,
 140         .send_IPI_allbutself            = default_send_IPI_allbutself,
 141         .send_IPI_all                   = default_send_IPI_all,
 142         .send_IPI_self                  = default_send_IPI_self,
 143
 144         .inquire_remote_apic            = default_inquire_remote_apic,
 145
 146         .read                           = native_apic_mem_read,
 147         .write                          = native_apic_mem_write,
 148         .eoi_write                      = native_apic_mem_write,
 149         .icr_read                       = native_apic_icr_read,
 150         .icr_write                      = native_apic_icr_write,
 151         .wait_icr_idle                  = native_apic_wait_icr_idle,
 152         .safe_wait_icr_idle             = native_safe_apic_wait_icr_idle,
 153 };
 154
 155 /*
 156  * Physflat mode is used when there are more than 8 CPUs on a system.
 157  * We cannot use logical delivery in this case because the mask
 158  * overflows, so use physical mode.
 159  */
 160 static int physflat_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
 161 {
 162 #ifdef CONFIG_ACPI
 163         /*
 164          * Quirk: some x86_64 machines can only use physical APIC mode
 165          * regardless of how many processors are present (x86_64 ES7000
 166          * is an example).
 167          */
 168         if (acpi_gbl_FADT.header.revision >= FADT2_REVISION_ID &&
 169                 (acpi_gbl_FADT.flags & ACPI_FADT_APIC_PHYSICAL)) {
 170                 printk(KERN_DEBUG "system APIC only can use physical flat");
 171                 return 1;
 172         }
 173
 174         if (!strncmp(oem_id, "IBM", 3) && !strncmp(oem_table_id, "EXA", 3)) {
 175                 printk(KERN_DEBUG "IBM Summit detected, will use apic physical");
 176                 return 1;
 177         }
 178 #endif
 179
 180         return 0;
 181 }
 182
 183 static void physflat_init_apic_ldr(void)
 184 {
 185         /*
 186          * LDR and DFR are not involved in physflat mode, rather:
 187          * "In physical destination mode, the destination processor is
 188          * specified by its local APIC ID [...]." (Intel SDM, 10.6.2.1)
 189          */
 190 }
 191
 192 static int physflat_probe(void)
 193 {
 194         if (apic == &apic_physflat || num_possible_cpus() > 8 ||
 195             jailhouse_paravirt())
 196                 return 1;
 197
 198         return 0;
 199 }
 200
 201 static struct apic apic_physflat __ro_after_init = {
 202
 203         .name                           = "physical flat",
 204         .probe                          = physflat_probe,
 205         .acpi_madt_oem_check            = physflat_acpi_madt_oem_check,
 206         .apic_id_valid                  = default_apic_id_valid,
 207         .apic_id_registered             = flat_apic_id_registered,
 208
 209         .irq_delivery_mode              = dest_Fixed,
 210         .irq_dest_mode                  = 0, /* physical */
 211
 212         .disable_esr                    = 0,
 213         .dest_logical                   = 0,
 214         .check_apicid_used              = NULL,
 215
 216         .init_apic_ldr                  = physflat_init_apic_ldr,
 217
 218         .ioapic_phys_id_map             = NULL,
 219         .setup_apic_routing             = NULL,
 220         .cpu_present_to_apicid          = default_cpu_present_to_apicid,
 221         .apicid_to_cpu_present          = NULL,
 222         .check_phys_apicid_present      = default_check_phys_apicid_present,
 223         .phys_pkg_id                    = flat_phys_pkg_id,
 224
 225         .get_apic_id                    = flat_get_apic_id,
 226         .set_apic_id                    = set_apic_id,
 227
 228         .calc_dest_apicid               = apic_default_calc_apicid,
 229
 230         .send_IPI                       = default_send_IPI_single_phys,
 231         .send_IPI_mask                  = default_send_IPI_mask_sequence_phys,
 232         .send_IPI_mask_allbutself       = default_send_IPI_mask_allbutself_phys,
 233         .send_IPI_allbutself            = default_send_IPI_allbutself,
 234         .send_IPI_all                   = default_send_IPI_all,
 235         .send_IPI_self                  = default_send_IPI_self,
 236
 237         .inquire_remote_apic            = default_inquire_remote_apic,
 238
 239         .read                           = native_apic_mem_read,
 240         .write                          = native_apic_mem_write,
 241         .eoi_write                      = native_apic_mem_write,
 242         .icr_read                       = native_apic_icr_read,
 243         .icr_write                      = native_apic_icr_write,
 244         .wait_icr_idle                  = native_apic_wait_icr_idle,
 245         .safe_wait_icr_idle             = native_safe_apic_wait_icr_idle,
 246 };
 247
 248 /*
 249  * We need to check for physflat first, so this order is important.
 250  */
 251 apic_drivers(apic_physflat, apic_flat);