1 /* 2 * Default generic APIC driver. This handles up to 8 CPUs. 3 * 4 * Copyright 2003 Andi Kleen, SuSE Labs. 5 * Subject to the GNU Public License, v.2 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 /* should be called last. */ 70 static int probe_default(void) 71 { 72 return 1; 73 } 74 75 static struct apic apic_default __ro_after_init = { 76 77 .name = "default", 78 .probe = probe_default, 79 .acpi_madt_oem_check = NULL, 80 .apic_id_valid = default_apic_id_valid, 81 .apic_id_registered = default_apic_id_registered, 82 83 .irq_delivery_mode = dest_LowestPrio, 84 /* logical delivery broadcast to all CPUs: */ 85 .irq_dest_mode = 1, 86 87 .target_cpus = default_target_cpus, 88 .disable_esr = 0, 89 .dest_logical = APIC_DEST_LOGICAL, 90 .check_apicid_used = default_check_apicid_used, 91 92 .vector_allocation_domain = flat_vector_allocation_domain, 93 .init_apic_ldr = default_init_apic_ldr, 94 95 .ioapic_phys_id_map = default_ioapic_phys_id_map, 96 .setup_apic_routing = setup_apic_flat_routing, 97 .cpu_present_to_apicid = default_cpu_present_to_apicid, 98 .apicid_to_cpu_present = physid_set_mask_of_physid, 99 .check_phys_apicid_present = default_check_phys_apicid_present, 100 .phys_pkg_id = default_phys_pkg_id, 101 102 .get_apic_id = default_get_apic_id, 103 .set_apic_id = NULL, 104 105 .cpu_mask_to_apicid = flat_cpu_mask_to_apicid, 106 107 .send_IPI = default_send_IPI_single, 108 .send_IPI_mask = default_send_IPI_mask_logical, 109 .send_IPI_mask_allbutself = default_send_IPI_mask_allbutself_logical, 110 .send_IPI_allbutself = default_send_IPI_allbutself, 111 .send_IPI_all = default_send_IPI_all, 112 .send_IPI_self = default_send_IPI_self, 113 114 .inquire_remote_apic = default_inquire_remote_apic, 115 116 .read = native_apic_mem_read, 117 .write = native_apic_mem_write, 118 .eoi_write = native_apic_mem_write, 119 .icr_read = native_apic_icr_read, 120 .icr_write = native_apic_icr_write, 121 .wait_icr_idle = native_apic_wait_icr_idle, 122 .safe_wait_icr_idle = native_safe_apic_wait_icr_idle, 123 124 .x86_32_early_logical_apicid = default_x86_32_early_logical_apicid, 125 }; 126 127 apic_driver(apic_default); 128 129 struct apic *apic __ro_after_init = &apic_default; 130 EXPORT_SYMBOL_GPL(apic); 131 132 static int cmdline_apic __initdata; 133 static int __init parse_apic(char *arg) 134 { 135 struct apic **drv; 136 137 if (!arg) 138 return -EINVAL; 139 140 for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) { 141 if (!strcmp((*drv)->name, arg)) { 142 apic = *drv; 143 cmdline_apic = 1; 144 return 0; 145 } 146 } 147 148 /* Parsed again by __setup for debug/verbose */ 149 return 0; 150 } 151 early_param("apic", parse_apic); 152 153 void __init default_setup_apic_routing(void) 154 { 155 int version = boot_cpu_apic_version; 156 157 if (num_possible_cpus() > 8) { 158 switch (boot_cpu_data.x86_vendor) { 159 case X86_VENDOR_INTEL: 160 if (!APIC_XAPIC(version)) { 161 def_to_bigsmp = 0; 162 break; 163 } 164 /* If P4 and above fall through */ 165 case X86_VENDOR_AMD: 166 def_to_bigsmp = 1; 167 } 168 } 169 170 #ifdef CONFIG_X86_BIGSMP 171 /* 172 * This is used to switch to bigsmp mode when 173 * - There is no apic= option specified by the user 174 * - generic_apic_probe() has chosen apic_default as the sub_arch 175 * - we find more than 8 CPUs in acpi LAPIC listing with xAPIC support 176 */ 177 178 if (!cmdline_apic && apic == &apic_default) 179 generic_bigsmp_probe(); 180 #endif 181 182 if (apic->setup_apic_routing) 183 apic->setup_apic_routing(); 184 185 if (x86_platform.apic_post_init) 186 x86_platform.apic_post_init(); 187 } 188 189 void __init generic_apic_probe(void) 190 { 191 if (!cmdline_apic) { 192 struct apic **drv; 193 194 for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) { 195 if ((*drv)->probe()) { 196 apic = *drv; 197 break; 198 } 199 } 200 /* Not visible without early console */ 201 if (drv == __apicdrivers_end) 202 panic("Didn't find an APIC driver"); 203 } 204 printk(KERN_INFO "Using APIC driver %s\n", apic->name); 205 } 206 207 /* This function can switch the APIC even after the initial ->probe() */ 208 int __init default_acpi_madt_oem_check(char *oem_id, char *oem_table_id) 209 { 210 struct apic **drv; 211 212 for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) { 213 if (!(*drv)->acpi_madt_oem_check) 214 continue; 215 if (!(*drv)->acpi_madt_oem_check(oem_id, oem_table_id)) 216 continue; 217 218 if (!cmdline_apic) { 219 apic = *drv; 220 printk(KERN_INFO "Switched to APIC driver `%s'.\n", 221 apic->name); 222 } 223 return 1; 224 } 225 return 0; 226 } 227