1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright 2004 James Cleverdon, IBM. 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); 298