arch/x86/kernel/apic/apic_flat_64.c

   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/acpi.h>
  12 #include <linux/errno.h>
  13 #include <linux/threads.h>
  14 #include <linux/cpumask.h>
  15 #include <linux/string.h>
  16 #include <linux/kernel.h>
  17 #include <linux/ctype.h>
  18 #include <linux/hardirq.h>
  19 #include <linux/export.h>
  20
  21 #include <asm/smp.h>
  22 #include <asm/ipi.h>
  23 #include <asm/apic.h>
  24 #include <asm/apic_flat_64.h>
  25 #include <asm/jailhouse_para.h>
  26
  27 static struct apic apic_physflat;
  28 static struct apic apic_flat;
  29
  30 struct apic *apic __ro_after_init = &apic_flat;
  31 EXPORT_SYMBOL_GPL(apic);
  32
  33 static int flat_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
  34 {
  35         return 1;
  36 }
  37
  38 /*
  39  * Set up the logical destination ID.
  40  *
  41  * Intel recommends to set DFR, LDR and TPR before enabling
  42  * an APIC.  See e.g. "AP-388 82489DX User's Manual" (Intel
  43  * document number 292116).  So here it goes...
  44  */
  45 void flat_init_apic_ldr(void)
  46 {
  47         unsigned long val;
  48         unsigned long num, id;
  49
  50         num = smp_processor_id();
  51         id = 1UL << num;
  52         apic_write(APIC_DFR, APIC_DFR_FLAT);
  53         val = apic_read(APIC_LDR) & ~APIC_LDR_MASK;
  54         val |= SET_APIC_LOGICAL_ID(id);
  55         apic_write(APIC_LDR, val);
  56 }
  57
  58 static void _flat_send_IPI_mask(unsigned long mask, int vector)
  59 {
  60         unsigned long flags;
  61
  62         local_irq_save(flags);
  63         __default_send_IPI_dest_field(mask, vector, apic->dest_logical);
  64         local_irq_restore(flags);
  65 }
  66
  67 static void flat_send_IPI_mask(const struct cpumask *cpumask, int vector)
  68 {
  69         unsigned long mask = cpumask_bits(cpumask)[0];
  70
  71         _flat_send_IPI_mask(mask, vector);
  72 }
  73
  74 static void
  75 flat_send_IPI_mask_allbutself(const struct cpumask *cpumask, int vector)
  76 {
  77         unsigned long mask = cpumask_bits(cpumask)[0];
  78         int cpu = smp_processor_id();
  79
  80         if (cpu < BITS_PER_LONG)
  81                 clear_bit(cpu, &mask);
  82
  83         _flat_send_IPI_mask(mask, vector);
  84 }
  85
  86 static void flat_send_IPI_allbutself(int vector)
  87 {
  88         int cpu = smp_processor_id();
  89
  90         if (IS_ENABLED(CONFIG_HOTPLUG_CPU) || vector == NMI_VECTOR) {
  91                 if (!cpumask_equal(cpu_online_mask, cpumask_of(cpu))) {
  92                         unsigned long mask = cpumask_bits(cpu_online_mask)[0];
  93
  94                         if (cpu < BITS_PER_LONG)
  95                                 clear_bit(cpu, &mask);
  96
  97                         _flat_send_IPI_mask(mask, vector);
  98                 }
  99         } else if (num_online_cpus() > 1) {
 100                 __default_send_IPI_shortcut(APIC_DEST_ALLBUT,
 101                                             vector, apic->dest_logical);
 102         }
 103 }
 104
 105 static void flat_send_IPI_all(int vector)
 106 {
 107         if (vector == NMI_VECTOR) {
 108                 flat_send_IPI_mask(cpu_online_mask, vector);
 109         } else {
 110                 __default_send_IPI_shortcut(APIC_DEST_ALLINC,
 111                                             vector, apic->dest_logical);
 112         }
 113 }
 114
 115 static unsigned int flat_get_apic_id(unsigned long x)
 116 {
 117         return (x >> 24) & 0xFF;
 118 }
 119
 120 static u32 set_apic_id(unsigned int id)
 121 {
 122         return (id & 0xFF) << 24;
 123 }
 124
 125 static unsigned int read_xapic_id(void)
 126 {
 127         return flat_get_apic_id(apic_read(APIC_ID));
 128 }
 129
 130 static int flat_apic_id_registered(void)
 131 {
 132         return physid_isset(read_xapic_id(), phys_cpu_present_map);
 133 }
 134
 135 static int flat_phys_pkg_id(int initial_apic_id, int index_msb)
 136 {
 137         return initial_apic_id >> index_msb;
 138 }
 139
 140 static int flat_probe(void)
 141 {
 142         return 1;
 143 }
 144
 145 static struct apic apic_flat __ro_after_init = {
 146         .name                           = "flat",
 147         .probe                          = flat_probe,
 148         .acpi_madt_oem_check            = flat_acpi_madt_oem_check,
 149         .apic_id_valid                  = default_apic_id_valid,
 150         .apic_id_registered             = flat_apic_id_registered,
 151
 152         .irq_delivery_mode              = dest_Fixed,
 153         .irq_dest_mode                  = 1, /* logical */
 154
 155         .disable_esr                    = 0,
 156         .dest_logical                   = APIC_DEST_LOGICAL,
 157         .check_apicid_used              = NULL,
 158
 159         .init_apic_ldr                  = flat_init_apic_ldr,
 160
 161         .ioapic_phys_id_map             = NULL,
 162         .setup_apic_routing             = NULL,
 163         .cpu_present_to_apicid          = default_cpu_present_to_apicid,
 164         .apicid_to_cpu_present          = NULL,
 165         .check_phys_apicid_present      = default_check_phys_apicid_present,
 166         .phys_pkg_id                    = flat_phys_pkg_id,
 167
 168         .get_apic_id                    = flat_get_apic_id,
 169         .set_apic_id                    = set_apic_id,
 170
 171         .calc_dest_apicid               = apic_flat_calc_apicid,
 172
 173         .send_IPI                       = default_send_IPI_single,
 174         .send_IPI_mask                  = flat_send_IPI_mask,
 175         .send_IPI_mask_allbutself       = flat_send_IPI_mask_allbutself,
 176         .send_IPI_allbutself            = flat_send_IPI_allbutself,
 177         .send_IPI_all                   = flat_send_IPI_all,
 178         .send_IPI_self                  = apic_send_IPI_self,
 179
 180         .inquire_remote_apic            = default_inquire_remote_apic,
 181
 182         .read                           = native_apic_mem_read,
 183         .write                          = native_apic_mem_write,
 184         .eoi_write                      = native_apic_mem_write,
 185         .icr_read                       = native_apic_icr_read,
 186         .icr_write                      = native_apic_icr_write,
 187         .wait_icr_idle                  = native_apic_wait_icr_idle,
 188         .safe_wait_icr_idle             = native_safe_apic_wait_icr_idle,
 189 };
 190
 191 /*
 192  * Physflat mode is used when there are more than 8 CPUs on a system.
 193  * We cannot use logical delivery in this case because the mask
 194  * overflows, so use physical mode.
 195  */
 196 static int physflat_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
 197 {
 198 #ifdef CONFIG_ACPI
 199         /*
 200          * Quirk: some x86_64 machines can only use physical APIC mode
 201          * regardless of how many processors are present (x86_64 ES7000
 202          * is an example).
 203          */
 204         if (acpi_gbl_FADT.header.revision >= FADT2_REVISION_ID &&
 205                 (acpi_gbl_FADT.flags & ACPI_FADT_APIC_PHYSICAL)) {
 206                 printk(KERN_DEBUG "system APIC only can use physical flat");
 207                 return 1;
 208         }
 209
 210         if (!strncmp(oem_id, "IBM", 3) && !strncmp(oem_table_id, "EXA", 3)) {
 211                 printk(KERN_DEBUG "IBM Summit detected, will use apic physical");
 212                 return 1;
 213         }
 214 #endif
 215
 216         return 0;
 217 }
 218
 219 static void physflat_init_apic_ldr(void)
 220 {
 221         /*
 222          * LDR and DFR are not involved in physflat mode, rather:
 223          * "In physical destination mode, the destination processor is
 224          * specified by its local APIC ID [...]." (Intel SDM, 10.6.2.1)
 225          */
 226 }
 227
 228 static void physflat_send_IPI_allbutself(int vector)
 229 {
 230         default_send_IPI_mask_allbutself_phys(cpu_online_mask, vector);
 231 }
 232
 233 static void physflat_send_IPI_all(int vector)
 234 {
 235         default_send_IPI_mask_sequence_phys(cpu_online_mask, vector);
 236 }
 237
 238 static int physflat_probe(void)
 239 {
 240         if (apic == &apic_physflat || num_possible_cpus() > 8 ||
 241             jailhouse_paravirt())
 242                 return 1;
 243
 244         return 0;
 245 }
 246
 247 static struct apic apic_physflat __ro_after_init = {
 248
 249         .name                           = "physical flat",
 250         .probe                          = physflat_probe,
 251         .acpi_madt_oem_check            = physflat_acpi_madt_oem_check,
 252         .apic_id_valid                  = default_apic_id_valid,
 253         .apic_id_registered             = flat_apic_id_registered,
 254
 255         .irq_delivery_mode              = dest_Fixed,
 256         .irq_dest_mode                  = 0, /* physical */
 257
 258         .disable_esr                    = 0,
 259         .dest_logical                   = 0,
 260         .check_apicid_used              = NULL,
 261
 262         .init_apic_ldr                  = physflat_init_apic_ldr,
 263
 264         .ioapic_phys_id_map             = NULL,
 265         .setup_apic_routing             = NULL,
 266         .cpu_present_to_apicid          = default_cpu_present_to_apicid,
 267         .apicid_to_cpu_present          = NULL,
 268         .check_phys_apicid_present      = default_check_phys_apicid_present,
 269         .phys_pkg_id                    = flat_phys_pkg_id,
 270
 271         .get_apic_id                    = flat_get_apic_id,
 272         .set_apic_id                    = set_apic_id,
 273
 274         .calc_dest_apicid               = apic_default_calc_apicid,
 275
 276         .send_IPI                       = default_send_IPI_single_phys,
 277         .send_IPI_mask                  = default_send_IPI_mask_sequence_phys,
 278         .send_IPI_mask_allbutself       = default_send_IPI_mask_allbutself_phys,
 279         .send_IPI_allbutself            = physflat_send_IPI_allbutself,
 280         .send_IPI_all                   = physflat_send_IPI_all,
 281         .send_IPI_self                  = apic_send_IPI_self,
 282
 283         .inquire_remote_apic            = default_inquire_remote_apic,
 284
 285         .read                           = native_apic_mem_read,
 286         .write                          = native_apic_mem_write,
 287         .eoi_write                      = native_apic_mem_write,
 288         .icr_read                       = native_apic_icr_read,
 289         .icr_write                      = native_apic_icr_write,
 290         .wait_icr_idle                  = native_apic_wait_icr_idle,
 291         .safe_wait_icr_idle             = native_safe_apic_wait_icr_idle,
 292 };
 293
 294 /*
 295  * We need to check for physflat first, so this order is important.
 296  */
 297 apic_drivers(apic_physflat, apic_flat);