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/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
  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  */
  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
  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
  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
  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
  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
 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
 114 static unsigned int flat_get_apic_id(unsigned long x)
 115 {
 116         return (x >> 24) & 0xFF;
 117 }
 118
 119 static u32 set_apic_id(unsigned int id)
 120 {
 121         return (id & 0xFF) << 24;
 122 }
 123
 124 static unsigned int read_xapic_id(void)
 125 {
 126         return flat_get_apic_id(apic_read(APIC_ID));
 127 }
 128
 129 static int flat_apic_id_registered(void)
 130 {
 131         return physid_isset(read_xapic_id(), phys_cpu_present_map);
 132 }
 133
 134 static int flat_phys_pkg_id(int initial_apic_id, int index_msb)
 135 {
 136         return initial_apic_id >> index_msb;
 137 }
 138
 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  */
 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
 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
 227 static void physflat_send_IPI_allbutself(int vector)
 228 {
 229         default_send_IPI_mask_allbutself_phys(cpu_online_mask, vector);
 230 }
 231
 232 static void physflat_send_IPI_all(int vector)
 233 {
 234         default_send_IPI_mask_sequence_phys(cpu_online_mask, vector);
 235 }
 236
 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);