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 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 /* If P4 and above fall through */ 188 case X86_VENDOR_AMD: 189 def_to_bigsmp = 1; 190 } 191 } 192 193 #ifdef CONFIG_X86_BIGSMP 194 /* 195 * This is used to switch to bigsmp mode when 196 * - There is no apic= option specified by the user 197 * - generic_apic_probe() has chosen apic_default as the sub_arch 198 * - we find more than 8 CPUs in acpi LAPIC listing with xAPIC support 199 */ 200 201 if (!cmdline_apic && apic == &apic_default) 202 generic_bigsmp_probe(); 203 #endif 204 205 if (apic->setup_apic_routing) 206 apic->setup_apic_routing(); 207 208 if (x86_platform.apic_post_init) 209 x86_platform.apic_post_init(); 210 } 211 212 void __init generic_apic_probe(void) 213 { 214 if (!cmdline_apic) { 215 struct apic **drv; 216 217 for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) { 218 if ((*drv)->probe()) { 219 apic = *drv; 220 break; 221 } 222 } 223 /* Not visible without early console */ 224 if (drv == __apicdrivers_end) 225 panic("Didn't find an APIC driver"); 226 } 227 printk(KERN_INFO "Using APIC driver %s\n", apic->name); 228 } 229 230 /* This function can switch the APIC even after the initial ->probe() */ 231 int __init default_acpi_madt_oem_check(char *oem_id, char *oem_table_id) 232 { 233 struct apic **drv; 234 235 for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) { 236 if (!(*drv)->acpi_madt_oem_check) 237 continue; 238 if (!(*drv)->acpi_madt_oem_check(oem_id, oem_table_id)) 239 continue; 240 241 if (!cmdline_apic) { 242 apic = *drv; 243 printk(KERN_INFO "Switched to APIC driver `%s'.\n", 244 apic->name); 245 } 246 return 1; 247 } 248 return 0; 249 } 250