1 /* 2 * QEMU ACPI hotplug utilities 3 * 4 * Copyright (C) 2013 Red Hat Inc 5 * 6 * Authors: 7 * Igor Mammedov <imammedo@redhat.com> 8 * 9 * This work is licensed under the terms of the GNU GPL, version 2 or later. 10 * See the COPYING file in the top-level directory. 11 */ 12 #include "qemu/osdep.h" 13 #include "hw/acpi/cpu_hotplug.h" 14 #include "qapi/error.h" 15 #include "hw/core/cpu.h" 16 #include "hw/i386/x86.h" 17 #include "hw/pci/pci_device.h" 18 #include "qemu/error-report.h" 19 20 #define CPU_EJECT_METHOD "CPEJ" 21 #define CPU_MAT_METHOD "CPMA" 22 #define CPU_ON_BITMAP "CPON" 23 #define CPU_STATUS_METHOD "CPST" 24 #define CPU_STATUS_MAP "PRS" 25 #define CPU_SCAN_METHOD "PRSC" 26 27 static uint64_t cpu_status_read(void *opaque, hwaddr addr, unsigned int size) 28 { 29 AcpiCpuHotplug *cpus = opaque; 30 uint64_t val = cpus->sts[addr]; 31 32 return val; 33 } 34 35 static void cpu_status_write(void *opaque, hwaddr addr, uint64_t data, 36 unsigned int size) 37 { 38 /* firmware never used to write in CPU present bitmap so use 39 this fact as means to switch QEMU into modern CPU hotplug 40 mode by writing 0 at the beginning of legacy CPU bitmap 41 */ 42 if (addr == 0 && data == 0) { 43 AcpiCpuHotplug *cpus = opaque; 44 object_property_set_bool(cpus->device, "cpu-hotplug-legacy", false, 45 &error_abort); 46 } 47 } 48 49 static const MemoryRegionOps AcpiCpuHotplug_ops = { 50 .read = cpu_status_read, 51 .write = cpu_status_write, 52 .endianness = DEVICE_LITTLE_ENDIAN, 53 .valid = { 54 .min_access_size = 1, 55 .max_access_size = 4, 56 }, 57 .impl = { 58 .max_access_size = 1, 59 }, 60 }; 61 62 static void acpi_set_cpu_present_bit(AcpiCpuHotplug *g, CPUState *cpu, 63 bool *swtchd_to_modern) 64 { 65 CPUClass *k = CPU_GET_CLASS(cpu); 66 int64_t cpu_id; 67 68 cpu_id = k->get_arch_id(cpu); 69 if ((cpu_id / 8) >= ACPI_GPE_PROC_LEN) { 70 object_property_set_bool(g->device, "cpu-hotplug-legacy", false, 71 &error_abort); 72 *swtchd_to_modern = true; 73 return; 74 } 75 76 *swtchd_to_modern = false; 77 g->sts[cpu_id / 8] |= (1 << (cpu_id % 8)); 78 } 79 80 void legacy_acpi_cpu_plug_cb(HotplugHandler *hotplug_dev, 81 AcpiCpuHotplug *g, DeviceState *dev, Error **errp) 82 { 83 bool swtchd_to_modern; 84 Error *local_err = NULL; 85 86 acpi_set_cpu_present_bit(g, CPU(dev), &swtchd_to_modern); 87 if (swtchd_to_modern) { 88 /* propagate the hotplug to the modern interface */ 89 hotplug_handler_plug(hotplug_dev, dev, &local_err); 90 } else { 91 acpi_send_event(DEVICE(hotplug_dev), ACPI_CPU_HOTPLUG_STATUS); 92 } 93 } 94 95 void legacy_acpi_cpu_hotplug_init(MemoryRegion *parent, Object *owner, 96 AcpiCpuHotplug *gpe_cpu, uint16_t base) 97 { 98 CPUState *cpu; 99 bool swtchd_to_modern; 100 101 memory_region_init_io(&gpe_cpu->io, owner, &AcpiCpuHotplug_ops, 102 gpe_cpu, "acpi-cpu-hotplug", ACPI_GPE_PROC_LEN); 103 memory_region_add_subregion(parent, base, &gpe_cpu->io); 104 gpe_cpu->device = owner; 105 106 CPU_FOREACH(cpu) { 107 acpi_set_cpu_present_bit(gpe_cpu, cpu, &swtchd_to_modern); 108 } 109 } 110 111 void acpi_switch_to_modern_cphp(AcpiCpuHotplug *gpe_cpu, 112 CPUHotplugState *cpuhp_state, 113 uint16_t io_port) 114 { 115 MemoryRegion *parent = pci_address_space_io(PCI_DEVICE(gpe_cpu->device)); 116 117 memory_region_del_subregion(parent, &gpe_cpu->io); 118 cpu_hotplug_hw_init(parent, gpe_cpu->device, cpuhp_state, io_port); 119 } 120 121 void build_legacy_cpu_hotplug_aml(Aml *ctx, MachineState *machine, 122 uint16_t io_base) 123 { 124 Aml *dev; 125 Aml *crs; 126 Aml *pkg; 127 Aml *field; 128 Aml *method; 129 Aml *if_ctx; 130 Aml *else_ctx; 131 int i, apic_idx; 132 Aml *sb_scope = aml_scope("_SB"); 133 uint8_t madt_tmpl[8] = {0x00, 0x08, 0x00, 0x00, 0x00, 0, 0, 0}; 134 Aml *cpu_id = aml_arg(1); 135 Aml *apic_id = aml_arg(0); 136 Aml *cpu_on = aml_local(0); 137 Aml *madt = aml_local(1); 138 Aml *cpus_map = aml_name(CPU_ON_BITMAP); 139 Aml *zero = aml_int(0); 140 Aml *one = aml_int(1); 141 MachineClass *mc = MACHINE_GET_CLASS(machine); 142 const CPUArchIdList *apic_ids = mc->possible_cpu_arch_ids(machine); 143 X86MachineState *x86ms = X86_MACHINE(machine); 144 145 /* 146 * _MAT method - creates an madt apic buffer 147 * apic_id = Arg0 = Local APIC ID 148 * cpu_id = Arg1 = Processor ID 149 * cpu_on = Local0 = CPON flag for this cpu 150 * madt = Local1 = Buffer (in madt apic form) to return 151 */ 152 method = aml_method(CPU_MAT_METHOD, 2, AML_NOTSERIALIZED); 153 aml_append(method, 154 aml_store(aml_derefof(aml_index(cpus_map, apic_id)), cpu_on)); 155 aml_append(method, 156 aml_store(aml_buffer(sizeof(madt_tmpl), madt_tmpl), madt)); 157 /* Update the processor id, lapic id, and enable/disable status */ 158 aml_append(method, aml_store(cpu_id, aml_index(madt, aml_int(2)))); 159 aml_append(method, aml_store(apic_id, aml_index(madt, aml_int(3)))); 160 aml_append(method, aml_store(cpu_on, aml_index(madt, aml_int(4)))); 161 aml_append(method, aml_return(madt)); 162 aml_append(sb_scope, method); 163 164 /* 165 * _STA method - return ON status of cpu 166 * apic_id = Arg0 = Local APIC ID 167 * cpu_on = Local0 = CPON flag for this cpu 168 */ 169 method = aml_method(CPU_STATUS_METHOD, 1, AML_NOTSERIALIZED); 170 aml_append(method, 171 aml_store(aml_derefof(aml_index(cpus_map, apic_id)), cpu_on)); 172 if_ctx = aml_if(cpu_on); 173 { 174 aml_append(if_ctx, aml_return(aml_int(0xF))); 175 } 176 aml_append(method, if_ctx); 177 else_ctx = aml_else(); 178 { 179 aml_append(else_ctx, aml_return(zero)); 180 } 181 aml_append(method, else_ctx); 182 aml_append(sb_scope, method); 183 184 method = aml_method(CPU_EJECT_METHOD, 2, AML_NOTSERIALIZED); 185 aml_append(method, aml_sleep(200)); 186 aml_append(sb_scope, method); 187 188 method = aml_method(CPU_SCAN_METHOD, 0, AML_NOTSERIALIZED); 189 { 190 Aml *while_ctx, *if_ctx2, *else_ctx2; 191 Aml *bus_check_evt = aml_int(1); 192 Aml *remove_evt = aml_int(3); 193 Aml *status_map = aml_local(5); /* Local5 = active cpu bitmap */ 194 Aml *byte = aml_local(2); /* Local2 = last read byte from bitmap */ 195 Aml *idx = aml_local(0); /* Processor ID / APIC ID iterator */ 196 Aml *is_cpu_on = aml_local(1); /* Local1 = CPON flag for cpu */ 197 Aml *status = aml_local(3); /* Local3 = active state for cpu */ 198 199 aml_append(method, aml_store(aml_name(CPU_STATUS_MAP), status_map)); 200 aml_append(method, aml_store(zero, byte)); 201 aml_append(method, aml_store(zero, idx)); 202 203 /* While (idx < SizeOf(CPON)) */ 204 while_ctx = aml_while(aml_lless(idx, aml_sizeof(cpus_map))); 205 aml_append(while_ctx, 206 aml_store(aml_derefof(aml_index(cpus_map, idx)), is_cpu_on)); 207 208 if_ctx = aml_if(aml_and(idx, aml_int(0x07), NULL)); 209 { 210 /* Shift down previously read bitmap byte */ 211 aml_append(if_ctx, aml_shiftright(byte, one, byte)); 212 } 213 aml_append(while_ctx, if_ctx); 214 215 else_ctx = aml_else(); 216 { 217 /* Read next byte from cpu bitmap */ 218 aml_append(else_ctx, aml_store(aml_derefof(aml_index(status_map, 219 aml_shiftright(idx, aml_int(3), NULL))), byte)); 220 } 221 aml_append(while_ctx, else_ctx); 222 223 aml_append(while_ctx, aml_store(aml_and(byte, one, NULL), status)); 224 if_ctx = aml_if(aml_lnot(aml_equal(is_cpu_on, status))); 225 { 226 /* State change - update CPON with new state */ 227 aml_append(if_ctx, aml_store(status, aml_index(cpus_map, idx))); 228 if_ctx2 = aml_if(aml_equal(status, one)); 229 { 230 aml_append(if_ctx2, 231 aml_call2(AML_NOTIFY_METHOD, idx, bus_check_evt)); 232 } 233 aml_append(if_ctx, if_ctx2); 234 else_ctx2 = aml_else(); 235 { 236 aml_append(else_ctx2, 237 aml_call2(AML_NOTIFY_METHOD, idx, remove_evt)); 238 } 239 } 240 aml_append(if_ctx, else_ctx2); 241 aml_append(while_ctx, if_ctx); 242 243 aml_append(while_ctx, aml_increment(idx)); /* go to next cpu */ 244 aml_append(method, while_ctx); 245 } 246 aml_append(sb_scope, method); 247 248 /* The current AML generator can cover the APIC ID range [0..255], 249 * inclusive, for VCPU hotplug. */ 250 QEMU_BUILD_BUG_ON(ACPI_CPU_HOTPLUG_ID_LIMIT > 256); 251 if (x86ms->apic_id_limit > ACPI_CPU_HOTPLUG_ID_LIMIT) { 252 error_report("max_cpus is too large. APIC ID of last CPU is %u", 253 x86ms->apic_id_limit - 1); 254 exit(1); 255 } 256 257 /* create PCI0.PRES device and its _CRS to reserve CPU hotplug MMIO */ 258 dev = aml_device("PCI0." stringify(CPU_HOTPLUG_RESOURCE_DEVICE)); 259 aml_append(dev, aml_name_decl("_HID", aml_eisaid("PNP0A06"))); 260 aml_append(dev, 261 aml_name_decl("_UID", aml_string("CPU Hotplug resources")) 262 ); 263 /* device present, functioning, decoding, not shown in UI */ 264 aml_append(dev, aml_name_decl("_STA", aml_int(0xB))); 265 crs = aml_resource_template(); 266 aml_append(crs, 267 aml_io(AML_DECODE16, io_base, io_base, 1, ACPI_GPE_PROC_LEN) 268 ); 269 aml_append(dev, aml_name_decl("_CRS", crs)); 270 aml_append(sb_scope, dev); 271 /* declare CPU hotplug MMIO region and PRS field to access it */ 272 aml_append(sb_scope, aml_operation_region( 273 "PRST", AML_SYSTEM_IO, aml_int(io_base), ACPI_GPE_PROC_LEN)); 274 field = aml_field("PRST", AML_BYTE_ACC, AML_NOLOCK, AML_PRESERVE); 275 aml_append(field, aml_named_field("PRS", 256)); 276 aml_append(sb_scope, field); 277 278 /* build Processor object for each processor */ 279 for (i = 0; i < apic_ids->len; i++) { 280 int cpu_apic_id = apic_ids->cpus[i].arch_id; 281 282 assert(cpu_apic_id < ACPI_CPU_HOTPLUG_ID_LIMIT); 283 284 dev = aml_processor(i, 0, 0, "CP%.02X", cpu_apic_id); 285 286 method = aml_method("_MAT", 0, AML_NOTSERIALIZED); 287 aml_append(method, 288 aml_return(aml_call2(CPU_MAT_METHOD, 289 aml_int(cpu_apic_id), aml_int(i)) 290 )); 291 aml_append(dev, method); 292 293 method = aml_method("_STA", 0, AML_NOTSERIALIZED); 294 aml_append(method, 295 aml_return(aml_call1(CPU_STATUS_METHOD, aml_int(cpu_apic_id)))); 296 aml_append(dev, method); 297 298 method = aml_method("_EJ0", 1, AML_NOTSERIALIZED); 299 aml_append(method, 300 aml_return(aml_call2(CPU_EJECT_METHOD, aml_int(cpu_apic_id), 301 aml_arg(0))) 302 ); 303 aml_append(dev, method); 304 305 aml_append(sb_scope, dev); 306 } 307 308 /* build this code: 309 * Method(NTFY, 2) {If (LEqual(Arg0, 0x00)) {Notify(CP00, Arg1)} ...} 310 */ 311 /* Arg0 = APIC ID */ 312 method = aml_method(AML_NOTIFY_METHOD, 2, AML_NOTSERIALIZED); 313 for (i = 0; i < apic_ids->len; i++) { 314 int cpu_apic_id = apic_ids->cpus[i].arch_id; 315 316 if_ctx = aml_if(aml_equal(aml_arg(0), aml_int(cpu_apic_id))); 317 aml_append(if_ctx, 318 aml_notify(aml_name("CP%.02X", cpu_apic_id), aml_arg(1)) 319 ); 320 aml_append(method, if_ctx); 321 } 322 aml_append(sb_scope, method); 323 324 /* build "Name(CPON, Package() { One, One, ..., Zero, Zero, ... })" 325 * 326 * Note: The ability to create variable-sized packages was first 327 * introduced in ACPI 2.0. ACPI 1.0 only allowed fixed-size packages 328 * ith up to 255 elements. Windows guests up to win2k8 fail when 329 * VarPackageOp is used. 330 */ 331 pkg = x86ms->apic_id_limit <= 255 ? aml_package(x86ms->apic_id_limit) : 332 aml_varpackage(x86ms->apic_id_limit); 333 334 for (i = 0, apic_idx = 0; i < apic_ids->len; i++) { 335 int cpu_apic_id = apic_ids->cpus[i].arch_id; 336 337 for (; apic_idx < cpu_apic_id; apic_idx++) { 338 aml_append(pkg, aml_int(0)); 339 } 340 aml_append(pkg, aml_int(apic_ids->cpus[i].cpu ? 1 : 0)); 341 apic_idx = cpu_apic_id + 1; 342 } 343 aml_append(sb_scope, aml_name_decl(CPU_ON_BITMAP, pkg)); 344 aml_append(ctx, sb_scope); 345 346 method = aml_method("\\_GPE._E02", 0, AML_NOTSERIALIZED); 347 aml_append(method, aml_call0("\\_SB." CPU_SCAN_METHOD)); 348 aml_append(ctx, method); 349 } 350