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); 297