arch/x86/kernel/apic/probe_32.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Default generic APIC driver. This handles up to 8 CPUs.
   4  *
   5  * Copyright 2003 Andi Kleen, SuSE Labs.
   6  *
   7  * Generic x86 APIC driver probe layer.
   8  */
   9 #include <linux/threads.h>
  10 #include <linux/cpumask.h>
  11 #include <linux/export.h>
  12 #include <linux/string.h>
  13 #include <linux/kernel.h>
  14 #include <linux/ctype.h>
  15 #include <linux/init.h>
  16 #include <linux/errno.h>
  17 #include <asm/fixmap.h>
  18 #include <asm/mpspec.h>
  19 #include <asm/apicdef.h>
  20 #include <asm/apic.h>
  21 #include <asm/setup.h>
  22
  23 #include <linux/smp.h>
  24 #include <asm/ipi.h>
  25
  26 #include <linux/interrupt.h>
  27 #include <asm/acpi.h>
  28 #include <asm/e820/api.h>
  29
  30 #ifdef CONFIG_HOTPLUG_CPU
  31 #define DEFAULT_SEND_IPI        (1)
  32 #else
  33 #define DEFAULT_SEND_IPI        (0)
  34 #endif
  35
  36 int no_broadcast = DEFAULT_SEND_IPI;
  37
  38 static __init int no_ipi_broadcast(char *str)
  39 {
  40         get_option(&str, &no_broadcast);
  41         pr_info("Using %s mode\n",
  42                 no_broadcast ? "No IPI Broadcast" : "IPI Broadcast");
  43         return 1;
  44 }
  45 __setup("no_ipi_broadcast=", no_ipi_broadcast);
  46
  47 static int __init print_ipi_mode(void)
  48 {
  49         pr_info("Using IPI %s mode\n",
  50                 no_broadcast ? "No-Shortcut" : "Shortcut");
  51         return 0;
  52 }
  53 late_initcall(print_ipi_mode);
  54
  55 static int default_x86_32_early_logical_apicid(int cpu)
  56 {
  57         return 1 << cpu;
  58 }
  59
  60 static void setup_apic_flat_routing(void)
  61 {
  62 #ifdef CONFIG_X86_IO_APIC
  63         printk(KERN_INFO
  64                 "Enabling APIC mode:  Flat.  Using %d I/O APICs\n",
  65                 nr_ioapics);
  66 #endif
  67 }
  68
  69 static int default_apic_id_registered(void)
  70 {
  71         return physid_isset(read_apic_id(), phys_cpu_present_map);
  72 }
  73
  74 /*
  75  * Set up the logical destination ID.  Intel recommends to set DFR, LDR and
  76  * TPR before enabling an APIC.  See e.g. "AP-388 82489DX User's Manual"
  77  * (Intel document number 292116).
  78  */
  79 static void default_init_apic_ldr(void)
  80 {
  81         unsigned long val;
  82
  83         apic_write(APIC_DFR, APIC_DFR_VALUE);
  84         val = apic_read(APIC_LDR) & ~APIC_LDR_MASK;
  85         val |= SET_APIC_LOGICAL_ID(1UL << smp_processor_id());
  86         apic_write(APIC_LDR, val);
  87 }
  88
  89 static int default_phys_pkg_id(int cpuid_apic, int index_msb)
  90 {
  91         return cpuid_apic >> index_msb;
  92 }
  93
  94 /* should be called last. */
  95 static int probe_default(void)
  96 {
  97         return 1;
  98 }
  99
 100 static struct apic apic_default __ro_after_init = {
 101
 102         .name                           = "default",
 103         .probe                          = probe_default,
 104         .acpi_madt_oem_check            = NULL,
 105         .apic_id_valid                  = default_apic_id_valid,
 106         .apic_id_registered             = default_apic_id_registered,
 107
 108         .irq_delivery_mode              = dest_Fixed,
 109         /* logical delivery broadcast to all CPUs: */
 110         .irq_dest_mode                  = 1,
 111
 112         .disable_esr                    = 0,
 113         .dest_logical                   = APIC_DEST_LOGICAL,
 114         .check_apicid_used              = default_check_apicid_used,
 115
 116         .init_apic_ldr                  = default_init_apic_ldr,
 117
 118         .ioapic_phys_id_map             = default_ioapic_phys_id_map,
 119         .setup_apic_routing             = setup_apic_flat_routing,
 120         .cpu_present_to_apicid          = default_cpu_present_to_apicid,
 121         .apicid_to_cpu_present          = physid_set_mask_of_physid,
 122         .check_phys_apicid_present      = default_check_phys_apicid_present,
 123         .phys_pkg_id                    = default_phys_pkg_id,
 124
 125         .get_apic_id                    = default_get_apic_id,
 126         .set_apic_id                    = NULL,
 127
 128         .calc_dest_apicid               = apic_flat_calc_apicid,
 129
 130         .send_IPI                       = default_send_IPI_single,
 131         .send_IPI_mask                  = default_send_IPI_mask_logical,
 132         .send_IPI_mask_allbutself       = default_send_IPI_mask_allbutself_logical,
 133         .send_IPI_allbutself            = default_send_IPI_allbutself,
 134         .send_IPI_all                   = default_send_IPI_all,
 135         .send_IPI_self                  = default_send_IPI_self,
 136
 137         .inquire_remote_apic            = default_inquire_remote_apic,
 138
 139         .read                           = native_apic_mem_read,
 140         .write                          = native_apic_mem_write,
 141         .eoi_write                      = native_apic_mem_write,
 142         .icr_read                       = native_apic_icr_read,
 143         .icr_write                      = native_apic_icr_write,
 144         .wait_icr_idle                  = native_apic_wait_icr_idle,
 145         .safe_wait_icr_idle             = native_safe_apic_wait_icr_idle,
 146
 147         .x86_32_early_logical_apicid    = default_x86_32_early_logical_apicid,
 148 };
 149
 150 apic_driver(apic_default);
 151
 152 struct apic *apic __ro_after_init = &apic_default;
 153 EXPORT_SYMBOL_GPL(apic);
 154
 155 static int cmdline_apic __initdata;
 156 static int __init parse_apic(char *arg)
 157 {
 158         struct apic **drv;
 159
 160         if (!arg)
 161                 return -EINVAL;
 162
 163         for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) {
 164                 if (!strcmp((*drv)->name, arg)) {
 165                         apic = *drv;
 166                         cmdline_apic = 1;
 167                         return 0;
 168                 }
 169         }
 170
 171         /* Parsed again by __setup for debug/verbose */
 172         return 0;
 173 }
 174 early_param("apic", parse_apic);
 175
 176 void __init default_setup_apic_routing(void)
 177 {
 178         int version = boot_cpu_apic_version;
 179
 180         if (num_possible_cpus() > 8) {
 181                 switch (boot_cpu_data.x86_vendor) {
 182                 case X86_VENDOR_INTEL:
 183                         if (!APIC_XAPIC(version)) {
 184                                 def_to_bigsmp = 0;
 185                                 break;
 186                         }
 187                         /* P4 and above */
 188                         /* fall through */
 189                 case X86_VENDOR_HYGON:
 190                 case X86_VENDOR_AMD:
 191                         def_to_bigsmp = 1;
 192                 }
 193         }
 194
 195 #ifdef CONFIG_X86_BIGSMP
 196         /*
 197          * This is used to switch to bigsmp mode when
 198          * - There is no apic= option specified by the user
 199          * - generic_apic_probe() has chosen apic_default as the sub_arch
 200          * - we find more than 8 CPUs in acpi LAPIC listing with xAPIC support
 201          */
 202
 203         if (!cmdline_apic && apic == &apic_default)
 204                 generic_bigsmp_probe();
 205 #endif
 206
 207         if (apic->setup_apic_routing)
 208                 apic->setup_apic_routing();
 209
 210         if (x86_platform.apic_post_init)
 211                 x86_platform.apic_post_init();
 212 }
 213
 214 void __init generic_apic_probe(void)
 215 {
 216         if (!cmdline_apic) {
 217                 struct apic **drv;
 218
 219                 for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) {
 220                         if ((*drv)->probe()) {
 221                                 apic = *drv;
 222                                 break;
 223                         }
 224                 }
 225                 /* Not visible without early console */
 226                 if (drv == __apicdrivers_end)
 227                         panic("Didn't find an APIC driver");
 228         }
 229         printk(KERN_INFO "Using APIC driver %s\n", apic->name);
 230 }
 231
 232 /* This function can switch the APIC even after the initial ->probe() */
 233 int __init default_acpi_madt_oem_check(char *oem_id, char *oem_table_id)
 234 {
 235         struct apic **drv;
 236
 237         for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) {
 238                 if (!(*drv)->acpi_madt_oem_check)
 239                         continue;
 240                 if (!(*drv)->acpi_madt_oem_check(oem_id, oem_table_id))
 241                         continue;
 242
 243                 if (!cmdline_apic) {
 244                         apic = *drv;
 245                         printk(KERN_INFO "Switched to APIC driver `%s'.\n",
 246                                apic->name);
 247                 }
 248                 return 1;
 249         }
 250         return 0;
 251 }