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 int64_t cpu_id; 66 67 cpu_id = cpu->cc->get_arch_id(cpu); 68 if ((cpu_id / 8) >= ACPI_GPE_PROC_LEN) { 69 object_property_set_bool(g->device, "cpu-hotplug-legacy", false, 70 &error_abort); 71 *swtchd_to_modern = true; 72 return; 73 } 74 75 *swtchd_to_modern = false; 76 g->sts[cpu_id / 8] |= (1 << (cpu_id % 8)); 77 } 78 79 void legacy_acpi_cpu_plug_cb(HotplugHandler *hotplug_dev, 80 AcpiCpuHotplug *g, DeviceState *dev, Error **errp) 81 { 82 bool swtchd_to_modern; 83 Error *local_err = NULL; 84 85 acpi_set_cpu_present_bit(g, CPU(dev), &swtchd_to_modern); 86 if (swtchd_to_modern) { 87 /* propagate the hotplug to the modern interface */ 88 hotplug_handler_plug(hotplug_dev, dev, &local_err); 89 } else { 90 acpi_send_event(DEVICE(hotplug_dev), ACPI_CPU_HOTPLUG_STATUS); 91 } 92 } 93 94 void legacy_acpi_cpu_hotplug_init(MemoryRegion *parent, Object *owner, 95 AcpiCpuHotplug *gpe_cpu, uint16_t base) 96 { 97 CPUState *cpu; 98 bool swtchd_to_modern; 99 100 memory_region_init_io(&gpe_cpu->io, owner, &AcpiCpuHotplug_ops, 101 gpe_cpu, "acpi-cpu-hotplug", ACPI_GPE_PROC_LEN); 102 memory_region_add_subregion(parent, base, &gpe_cpu->io); 103 gpe_cpu->device = owner; 104 105 CPU_FOREACH(cpu) { 106 acpi_set_cpu_present_bit(gpe_cpu, cpu, &swtchd_to_modern); 107 } 108 } 109 110 void acpi_switch_to_modern_cphp(AcpiCpuHotplug *gpe_cpu, 111 CPUHotplugState *cpuhp_state, 112 uint16_t io_port) 113 { 114 MemoryRegion *parent = pci_address_space_io(PCI_DEVICE(gpe_cpu->device)); 115 116 memory_region_del_subregion(parent, &gpe_cpu->io); 117 cpu_hotplug_hw_init(parent, gpe_cpu->device, cpuhp_state, io_port); 118 } 119 120 void build_legacy_cpu_hotplug_aml(Aml *ctx, MachineState *machine, 121 uint16_t io_base) 122 { 123 Aml *dev; 124 Aml *crs; 125 Aml *pkg; 126 Aml *field; 127 Aml *method; 128 Aml *if_ctx; 129 Aml *else_ctx; 130 int i, apic_idx; 131 Aml *sb_scope = aml_scope("_SB"); 132 uint8_t madt_tmpl[8] = {0x00, 0x08, 0x00, 0x00, 0x00, 0, 0, 0}; 133 Aml *cpu_id = aml_arg(1); 134 Aml *apic_id = aml_arg(0); 135 Aml *cpu_on = aml_local(0); 136 Aml *madt = aml_local(1); 137 Aml *cpus_map = aml_name(CPU_ON_BITMAP); 138 Aml *zero = aml_int(0); 139 Aml *one = aml_int(1); 140 MachineClass *mc = MACHINE_GET_CLASS(machine); 141 const CPUArchIdList *apic_ids = mc->possible_cpu_arch_ids(machine); 142 X86MachineState *x86ms = X86_MACHINE(machine); 143 144 /* 145 * _MAT method - creates an madt apic buffer 146 * apic_id = Arg0 = Local APIC ID 147 * cpu_id = Arg1 = Processor ID 148 * cpu_on = Local0 = CPON flag for this cpu 149 * madt = Local1 = Buffer (in madt apic form) to return 150 */ 151 method = aml_method(CPU_MAT_METHOD, 2, AML_NOTSERIALIZED); 152 aml_append(method, 153 aml_store(aml_derefof(aml_index(cpus_map, apic_id)), cpu_on)); 154 aml_append(method, 155 aml_store(aml_buffer(sizeof(madt_tmpl), madt_tmpl), madt)); 156 /* Update the processor id, lapic id, and enable/disable status */ 157 aml_append(method, aml_store(cpu_id, aml_index(madt, aml_int(2)))); 158 aml_append(method, aml_store(apic_id, aml_index(madt, aml_int(3)))); 159 aml_append(method, aml_store(cpu_on, aml_index(madt, aml_int(4)))); 160 aml_append(method, aml_return(madt)); 161 aml_append(sb_scope, method); 162 163 /* 164 * _STA method - return ON status of cpu 165 * apic_id = Arg0 = Local APIC ID 166 * cpu_on = Local0 = CPON flag for this cpu 167 */ 168 method = aml_method(CPU_STATUS_METHOD, 1, AML_NOTSERIALIZED); 169 aml_append(method, 170 aml_store(aml_derefof(aml_index(cpus_map, apic_id)), cpu_on)); 171 if_ctx = aml_if(cpu_on); 172 { 173 aml_append(if_ctx, aml_return(aml_int(0xF))); 174 } 175 aml_append(method, if_ctx); 176 else_ctx = aml_else(); 177 { 178 aml_append(else_ctx, aml_return(zero)); 179 } 180 aml_append(method, else_ctx); 181 aml_append(sb_scope, method); 182 183 method = aml_method(CPU_EJECT_METHOD, 2, AML_NOTSERIALIZED); 184 aml_append(method, aml_sleep(200)); 185 aml_append(sb_scope, method); 186 187 method = aml_method(CPU_SCAN_METHOD, 0, AML_NOTSERIALIZED); 188 { 189 Aml *while_ctx, *if_ctx2, *else_ctx2; 190 Aml *bus_check_evt = aml_int(1); 191 Aml *remove_evt = aml_int(3); 192 Aml *status_map = aml_local(5); /* Local5 = active cpu bitmap */ 193 Aml *byte = aml_local(2); /* Local2 = last read byte from bitmap */ 194 Aml *idx = aml_local(0); /* Processor ID / APIC ID iterator */ 195 Aml *is_cpu_on = aml_local(1); /* Local1 = CPON flag for cpu */ 196 Aml *status = aml_local(3); /* Local3 = active state for cpu */ 197 198 aml_append(method, aml_store(aml_name(CPU_STATUS_MAP), status_map)); 199 aml_append(method, aml_store(zero, byte)); 200 aml_append(method, aml_store(zero, idx)); 201 202 /* While (idx < SizeOf(CPON)) */ 203 while_ctx = aml_while(aml_lless(idx, aml_sizeof(cpus_map))); 204 aml_append(while_ctx, 205 aml_store(aml_derefof(aml_index(cpus_map, idx)), is_cpu_on)); 206 207 if_ctx = aml_if(aml_and(idx, aml_int(0x07), NULL)); 208 { 209 /* Shift down previously read bitmap byte */ 210 aml_append(if_ctx, aml_shiftright(byte, one, byte)); 211 } 212 aml_append(while_ctx, if_ctx); 213 214 else_ctx = aml_else(); 215 { 216 /* Read next byte from cpu bitmap */ 217 aml_append(else_ctx, aml_store(aml_derefof(aml_index(status_map, 218 aml_shiftright(idx, aml_int(3), NULL))), byte)); 219 } 220 aml_append(while_ctx, else_ctx); 221 222 aml_append(while_ctx, aml_store(aml_and(byte, one, NULL), status)); 223 if_ctx = aml_if(aml_lnot(aml_equal(is_cpu_on, status))); 224 { 225 /* State change - update CPON with new state */ 226 aml_append(if_ctx, aml_store(status, aml_index(cpus_map, idx))); 227 if_ctx2 = aml_if(aml_equal(status, one)); 228 { 229 aml_append(if_ctx2, 230 aml_call2(AML_NOTIFY_METHOD, idx, bus_check_evt)); 231 } 232 aml_append(if_ctx, if_ctx2); 233 else_ctx2 = aml_else(); 234 { 235 aml_append(else_ctx2, 236 aml_call2(AML_NOTIFY_METHOD, idx, remove_evt)); 237 } 238 } 239 aml_append(if_ctx, else_ctx2); 240 aml_append(while_ctx, if_ctx); 241 242 aml_append(while_ctx, aml_increment(idx)); /* go to next cpu */ 243 aml_append(method, while_ctx); 244 } 245 aml_append(sb_scope, method); 246 247 /* The current AML generator can cover the APIC ID range [0..255], 248 * inclusive, for VCPU hotplug. */ 249 QEMU_BUILD_BUG_ON(ACPI_CPU_HOTPLUG_ID_LIMIT > 256); 250 if (x86ms->apic_id_limit > ACPI_CPU_HOTPLUG_ID_LIMIT) { 251 error_report("max_cpus is too large. APIC ID of last CPU is %u", 252 x86ms->apic_id_limit - 1); 253 exit(1); 254 } 255 256 /* create PCI0.PRES device and its _CRS to reserve CPU hotplug MMIO */ 257 dev = aml_device("PCI0." stringify(CPU_HOTPLUG_RESOURCE_DEVICE)); 258 aml_append(dev, aml_name_decl("_HID", aml_eisaid("PNP0A06"))); 259 aml_append(dev, 260 aml_name_decl("_UID", aml_string("CPU Hotplug resources")) 261 ); 262 /* device present, functioning, decoding, not shown in UI */ 263 aml_append(dev, aml_name_decl("_STA", aml_int(0xB))); 264 crs = aml_resource_template(); 265 aml_append(crs, 266 aml_io(AML_DECODE16, io_base, io_base, 1, ACPI_GPE_PROC_LEN) 267 ); 268 aml_append(dev, aml_name_decl("_CRS", crs)); 269 aml_append(sb_scope, dev); 270 /* declare CPU hotplug MMIO region and PRS field to access it */ 271 aml_append(sb_scope, aml_operation_region( 272 "PRST", AML_SYSTEM_IO, aml_int(io_base), ACPI_GPE_PROC_LEN)); 273 field = aml_field("PRST", AML_BYTE_ACC, AML_NOLOCK, AML_PRESERVE); 274 aml_append(field, aml_named_field("PRS", 256)); 275 aml_append(sb_scope, field); 276 277 /* build Processor object for each processor */ 278 for (i = 0; i < apic_ids->len; i++) { 279 int cpu_apic_id = apic_ids->cpus[i].arch_id; 280 281 assert(cpu_apic_id < ACPI_CPU_HOTPLUG_ID_LIMIT); 282 283 dev = aml_processor(i, 0, 0, "CP%.02X", cpu_apic_id); 284 285 method = aml_method("_MAT", 0, AML_NOTSERIALIZED); 286 aml_append(method, 287 aml_return(aml_call2(CPU_MAT_METHOD, 288 aml_int(cpu_apic_id), aml_int(i)) 289 )); 290 aml_append(dev, method); 291 292 method = aml_method("_STA", 0, AML_NOTSERIALIZED); 293 aml_append(method, 294 aml_return(aml_call1(CPU_STATUS_METHOD, aml_int(cpu_apic_id)))); 295 aml_append(dev, method); 296 297 method = aml_method("_EJ0", 1, AML_NOTSERIALIZED); 298 aml_append(method, 299 aml_return(aml_call2(CPU_EJECT_METHOD, aml_int(cpu_apic_id), 300 aml_arg(0))) 301 ); 302 aml_append(dev, method); 303 304 aml_append(sb_scope, dev); 305 } 306 307 /* build this code: 308 * Method(NTFY, 2) {If (LEqual(Arg0, 0x00)) {Notify(CP00, Arg1)} ...} 309 */ 310 /* Arg0 = APIC ID */ 311 method = aml_method(AML_NOTIFY_METHOD, 2, AML_NOTSERIALIZED); 312 for (i = 0; i < apic_ids->len; i++) { 313 int cpu_apic_id = apic_ids->cpus[i].arch_id; 314 315 if_ctx = aml_if(aml_equal(aml_arg(0), aml_int(cpu_apic_id))); 316 aml_append(if_ctx, 317 aml_notify(aml_name("CP%.02X", cpu_apic_id), aml_arg(1)) 318 ); 319 aml_append(method, if_ctx); 320 } 321 aml_append(sb_scope, method); 322 323 /* build "Name(CPON, Package() { One, One, ..., Zero, Zero, ... })" 324 * 325 * Note: The ability to create variable-sized packages was first 326 * introduced in ACPI 2.0. ACPI 1.0 only allowed fixed-size packages 327 * ith up to 255 elements. Windows guests up to win2k8 fail when 328 * VarPackageOp is used. 329 */ 330 pkg = x86ms->apic_id_limit <= 255 ? aml_package(x86ms->apic_id_limit) : 331 aml_varpackage(x86ms->apic_id_limit); 332 333 for (i = 0, apic_idx = 0; i < apic_ids->len; i++) { 334 int cpu_apic_id = apic_ids->cpus[i].arch_id; 335 336 for (; apic_idx < cpu_apic_id; apic_idx++) { 337 aml_append(pkg, aml_int(0)); 338 } 339 aml_append(pkg, aml_int(apic_ids->cpus[i].cpu ? 1 : 0)); 340 apic_idx = cpu_apic_id + 1; 341 } 342 aml_append(sb_scope, aml_name_decl(CPU_ON_BITMAP, pkg)); 343 aml_append(ctx, sb_scope); 344 345 method = aml_method("\\_GPE._E02", 0, AML_NOTSERIALIZED); 346 aml_append(method, aml_call0("\\_SB." CPU_SCAN_METHOD)); 347 aml_append(ctx, method); 348 } 349