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 static void _flat_send_IPI_mask(unsigned long mask, int vector)
  32 {
  33         unsigned long flags;
  34
  35         local_irq_save(flags);
  36         __default_send_IPI_dest_field(mask, vector, APIC_DEST_LOGICAL);
  37         local_irq_restore(flags);
  38 }
  39
  40 static void flat_send_IPI_mask(const struct cpumask *cpumask, int vector)
  41 {
  42         unsigned long mask = cpumask_bits(cpumask)[0];
  43
  44         _flat_send_IPI_mask(mask, vector);
  45 }
  46
  47 static void
  48 flat_send_IPI_mask_allbutself(const struct cpumask *cpumask, int vector)
  49 {
  50         unsigned long mask = cpumask_bits(cpumask)[0];
  51         int cpu = smp_processor_id();
  52
  53         if (cpu < BITS_PER_LONG)
  54                 __clear_bit(cpu, &mask);
  55
  56         _flat_send_IPI_mask(mask, vector);
  57 }
  58
  59 static u32 flat_get_apic_id(u32 x)
  60 {
  61         return (x >> 24) & 0xFF;
  62 }
  63
  64 static int flat_probe(void)
  65 {
  66         return 1;
  67 }
  68
  69 static struct apic apic_flat __ro_after_init = {
  70         .name                           = "flat",
  71         .probe                          = flat_probe,
  72         .acpi_madt_oem_check            = flat_acpi_madt_oem_check,
  73
  74         .dest_mode_logical              = true,
  75
  76         .disable_esr                    = 0,
  77
  78         .init_apic_ldr                  = default_init_apic_ldr,
  79         .cpu_present_to_apicid          = default_cpu_present_to_apicid,
  80
  81         .max_apic_id                    = 0xFE,
  82         .get_apic_id                    = flat_get_apic_id,
  83
  84         .calc_dest_apicid               = apic_flat_calc_apicid,
  85
  86         .send_IPI                       = default_send_IPI_single,
  87         .send_IPI_mask                  = flat_send_IPI_mask,
  88         .send_IPI_mask_allbutself       = flat_send_IPI_mask_allbutself,
  89         .send_IPI_allbutself            = default_send_IPI_allbutself,
  90         .send_IPI_all                   = default_send_IPI_all,
  91         .send_IPI_self                  = default_send_IPI_self,
  92         .nmi_to_offline_cpu             = true,
  93
  94         .read                           = native_apic_mem_read,
  95         .write                          = native_apic_mem_write,
  96         .eoi                            = native_apic_mem_eoi,
  97         .icr_read                       = native_apic_icr_read,
  98         .icr_write                      = native_apic_icr_write,
  99         .wait_icr_idle                  = apic_mem_wait_icr_idle,
 100         .safe_wait_icr_idle             = apic_mem_wait_icr_idle_timeout,
 101 };
 102
 103 /*
 104  * Physflat mode is used when there are more than 8 CPUs on a system.
 105  * We cannot use logical delivery in this case because the mask
 106  * overflows, so use physical mode.
 107  */
 108 static int physflat_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
 109 {
 110 #ifdef CONFIG_ACPI
 111         /*
 112          * Quirk: some x86_64 machines can only use physical APIC mode
 113          * regardless of how many processors are present (x86_64 ES7000
 114          * is an example).
 115          */
 116         if (acpi_gbl_FADT.header.revision >= FADT2_REVISION_ID &&
 117                 (acpi_gbl_FADT.flags & ACPI_FADT_APIC_PHYSICAL)) {
 118                 printk(KERN_DEBUG "system APIC only can use physical flat");
 119                 return 1;
 120         }
 121
 122         if (!strncmp(oem_id, "IBM", 3) && !strncmp(oem_table_id, "EXA", 3)) {
 123                 printk(KERN_DEBUG "IBM Summit detected, will use apic physical");
 124                 return 1;
 125         }
 126 #endif
 127
 128         return 0;
 129 }
 130
 131 static int physflat_probe(void)
 132 {
 133         return apic == &apic_physflat || num_possible_cpus() > 8 || jailhouse_paravirt();
 134 }
 135
 136 static struct apic apic_physflat __ro_after_init = {
 137
 138         .name                           = "physical flat",
 139         .probe                          = physflat_probe,
 140         .acpi_madt_oem_check            = physflat_acpi_madt_oem_check,
 141
 142         .dest_mode_logical              = false,
 143
 144         .disable_esr                    = 0,
 145
 146         .cpu_present_to_apicid          = default_cpu_present_to_apicid,
 147
 148         .max_apic_id                    = 0xFE,
 149         .get_apic_id                    = flat_get_apic_id,
 150
 151         .calc_dest_apicid               = apic_default_calc_apicid,
 152
 153         .send_IPI                       = default_send_IPI_single_phys,
 154         .send_IPI_mask                  = default_send_IPI_mask_sequence_phys,
 155         .send_IPI_mask_allbutself       = default_send_IPI_mask_allbutself_phys,
 156         .send_IPI_allbutself            = default_send_IPI_allbutself,
 157         .send_IPI_all                   = default_send_IPI_all,
 158         .send_IPI_self                  = default_send_IPI_self,
 159         .nmi_to_offline_cpu             = true,
 160
 161         .read                           = native_apic_mem_read,
 162         .write                          = native_apic_mem_write,
 163         .eoi                            = native_apic_mem_eoi,
 164         .icr_read                       = native_apic_icr_read,
 165         .icr_write                      = native_apic_icr_write,
 166         .wait_icr_idle                  = apic_mem_wait_icr_idle,
 167         .safe_wait_icr_idle             = apic_mem_wait_icr_idle_timeout,
 168 };
 169
 170 /*
 171  * We need to check for physflat first, so this order is important.
 172  */
 173 apic_drivers(apic_physflat, apic_flat);