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/hw.h" 14 #include "hw/acpi/cpu_hotplug.h" 15 #include "qapi/error.h" 16 #include "qom/cpu.h" 17 #include "hw/i386/pc.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, false, "cpu-hotplug-legacy", 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 = 1, 56 }, 57 }; 58 59 static void acpi_set_cpu_present_bit(AcpiCpuHotplug *g, CPUState *cpu, 60 Error **errp) 61 { 62 CPUClass *k = CPU_GET_CLASS(cpu); 63 int64_t cpu_id; 64 65 cpu_id = k->get_arch_id(cpu); 66 if ((cpu_id / 8) >= ACPI_GPE_PROC_LEN) { 67 object_property_set_bool(g->device, false, "cpu-hotplug-legacy", 68 &error_abort); 69 return; 70 } 71 72 g->sts[cpu_id / 8] |= (1 << (cpu_id % 8)); 73 } 74 75 void legacy_acpi_cpu_plug_cb(HotplugHandler *hotplug_dev, 76 AcpiCpuHotplug *g, DeviceState *dev, Error **errp) 77 { 78 acpi_set_cpu_present_bit(g, CPU(dev), errp); 79 if (*errp != NULL) { 80 return; 81 } 82 acpi_send_event(DEVICE(hotplug_dev), ACPI_CPU_HOTPLUG_STATUS); 83 } 84 85 void legacy_acpi_cpu_hotplug_init(MemoryRegion *parent, Object *owner, 86 AcpiCpuHotplug *gpe_cpu, uint16_t base) 87 { 88 CPUState *cpu; 89 90 memory_region_init_io(&gpe_cpu->io, owner, &AcpiCpuHotplug_ops, 91 gpe_cpu, "acpi-cpu-hotplug", ACPI_GPE_PROC_LEN); 92 memory_region_add_subregion(parent, base, &gpe_cpu->io); 93 gpe_cpu->device = owner; 94 95 CPU_FOREACH(cpu) { 96 acpi_set_cpu_present_bit(gpe_cpu, cpu, &error_abort); 97 } 98 } 99 100 void acpi_switch_to_modern_cphp(AcpiCpuHotplug *gpe_cpu, 101 CPUHotplugState *cpuhp_state, 102 uint16_t io_port) 103 { 104 MemoryRegion *parent = pci_address_space_io(PCI_DEVICE(gpe_cpu->device)); 105 106 memory_region_del_subregion(parent, &gpe_cpu->io); 107 cpu_hotplug_hw_init(parent, gpe_cpu->device, cpuhp_state, io_port); 108 } 109 110 void build_legacy_cpu_hotplug_aml(Aml *ctx, MachineState *machine, 111 uint16_t io_base) 112 { 113 Aml *dev; 114 Aml *crs; 115 Aml *pkg; 116 Aml *field; 117 Aml *method; 118 Aml *if_ctx; 119 Aml *else_ctx; 120 int i, apic_idx; 121 Aml *sb_scope = aml_scope("_SB"); 122 uint8_t madt_tmpl[8] = {0x00, 0x08, 0x00, 0x00, 0x00, 0, 0, 0}; 123 Aml *cpu_id = aml_arg(1); 124 Aml *apic_id = aml_arg(0); 125 Aml *cpu_on = aml_local(0); 126 Aml *madt = aml_local(1); 127 Aml *cpus_map = aml_name(CPU_ON_BITMAP); 128 Aml *zero = aml_int(0); 129 Aml *one = aml_int(1); 130 MachineClass *mc = MACHINE_GET_CLASS(machine); 131 const CPUArchIdList *apic_ids = mc->possible_cpu_arch_ids(machine); 132 PCMachineState *pcms = PC_MACHINE(machine); 133 134 /* 135 * _MAT method - creates an madt apic buffer 136 * apic_id = Arg0 = Local APIC ID 137 * cpu_id = Arg1 = Processor ID 138 * cpu_on = Local0 = CPON flag for this cpu 139 * madt = Local1 = Buffer (in madt apic form) to return 140 */ 141 method = aml_method(CPU_MAT_METHOD, 2, AML_NOTSERIALIZED); 142 aml_append(method, 143 aml_store(aml_derefof(aml_index(cpus_map, apic_id)), cpu_on)); 144 aml_append(method, 145 aml_store(aml_buffer(sizeof(madt_tmpl), madt_tmpl), madt)); 146 /* Update the processor id, lapic id, and enable/disable status */ 147 aml_append(method, aml_store(cpu_id, aml_index(madt, aml_int(2)))); 148 aml_append(method, aml_store(apic_id, aml_index(madt, aml_int(3)))); 149 aml_append(method, aml_store(cpu_on, aml_index(madt, aml_int(4)))); 150 aml_append(method, aml_return(madt)); 151 aml_append(sb_scope, method); 152 153 /* 154 * _STA method - return ON status of cpu 155 * apic_id = Arg0 = Local APIC ID 156 * cpu_on = Local0 = CPON flag for this cpu 157 */ 158 method = aml_method(CPU_STATUS_METHOD, 1, AML_NOTSERIALIZED); 159 aml_append(method, 160 aml_store(aml_derefof(aml_index(cpus_map, apic_id)), cpu_on)); 161 if_ctx = aml_if(cpu_on); 162 { 163 aml_append(if_ctx, aml_return(aml_int(0xF))); 164 } 165 aml_append(method, if_ctx); 166 else_ctx = aml_else(); 167 { 168 aml_append(else_ctx, aml_return(zero)); 169 } 170 aml_append(method, else_ctx); 171 aml_append(sb_scope, method); 172 173 method = aml_method(CPU_EJECT_METHOD, 2, AML_NOTSERIALIZED); 174 aml_append(method, aml_sleep(200)); 175 aml_append(sb_scope, method); 176 177 method = aml_method(CPU_SCAN_METHOD, 0, AML_NOTSERIALIZED); 178 { 179 Aml *while_ctx, *if_ctx2, *else_ctx2; 180 Aml *bus_check_evt = aml_int(1); 181 Aml *remove_evt = aml_int(3); 182 Aml *status_map = aml_local(5); /* Local5 = active cpu bitmap */ 183 Aml *byte = aml_local(2); /* Local2 = last read byte from bitmap */ 184 Aml *idx = aml_local(0); /* Processor ID / APIC ID iterator */ 185 Aml *is_cpu_on = aml_local(1); /* Local1 = CPON flag for cpu */ 186 Aml *status = aml_local(3); /* Local3 = active state for cpu */ 187 188 aml_append(method, aml_store(aml_name(CPU_STATUS_MAP), status_map)); 189 aml_append(method, aml_store(zero, byte)); 190 aml_append(method, aml_store(zero, idx)); 191 192 /* While (idx < SizeOf(CPON)) */ 193 while_ctx = aml_while(aml_lless(idx, aml_sizeof(cpus_map))); 194 aml_append(while_ctx, 195 aml_store(aml_derefof(aml_index(cpus_map, idx)), is_cpu_on)); 196 197 if_ctx = aml_if(aml_and(idx, aml_int(0x07), NULL)); 198 { 199 /* Shift down previously read bitmap byte */ 200 aml_append(if_ctx, aml_shiftright(byte, one, byte)); 201 } 202 aml_append(while_ctx, if_ctx); 203 204 else_ctx = aml_else(); 205 { 206 /* Read next byte from cpu bitmap */ 207 aml_append(else_ctx, aml_store(aml_derefof(aml_index(status_map, 208 aml_shiftright(idx, aml_int(3), NULL))), byte)); 209 } 210 aml_append(while_ctx, else_ctx); 211 212 aml_append(while_ctx, aml_store(aml_and(byte, one, NULL), status)); 213 if_ctx = aml_if(aml_lnot(aml_equal(is_cpu_on, status))); 214 { 215 /* State change - update CPON with new state */ 216 aml_append(if_ctx, aml_store(status, aml_index(cpus_map, idx))); 217 if_ctx2 = aml_if(aml_equal(status, one)); 218 { 219 aml_append(if_ctx2, 220 aml_call2(AML_NOTIFY_METHOD, idx, bus_check_evt)); 221 } 222 aml_append(if_ctx, if_ctx2); 223 else_ctx2 = aml_else(); 224 { 225 aml_append(else_ctx2, 226 aml_call2(AML_NOTIFY_METHOD, idx, remove_evt)); 227 } 228 } 229 aml_append(if_ctx, else_ctx2); 230 aml_append(while_ctx, if_ctx); 231 232 aml_append(while_ctx, aml_increment(idx)); /* go to next cpu */ 233 aml_append(method, while_ctx); 234 } 235 aml_append(sb_scope, method); 236 237 /* The current AML generator can cover the APIC ID range [0..255], 238 * inclusive, for VCPU hotplug. */ 239 QEMU_BUILD_BUG_ON(ACPI_CPU_HOTPLUG_ID_LIMIT > 256); 240 if (pcms->apic_id_limit > ACPI_CPU_HOTPLUG_ID_LIMIT) { 241 error_report("max_cpus is too large. APIC ID of last CPU is %u", 242 pcms->apic_id_limit - 1); 243 exit(1); 244 } 245 246 /* create PCI0.PRES device and its _CRS to reserve CPU hotplug MMIO */ 247 dev = aml_device("PCI0." stringify(CPU_HOTPLUG_RESOURCE_DEVICE)); 248 aml_append(dev, aml_name_decl("_HID", aml_eisaid("PNP0A06"))); 249 aml_append(dev, 250 aml_name_decl("_UID", aml_string("CPU Hotplug resources")) 251 ); 252 /* device present, functioning, decoding, not shown in UI */ 253 aml_append(dev, aml_name_decl("_STA", aml_int(0xB))); 254 crs = aml_resource_template(); 255 aml_append(crs, 256 aml_io(AML_DECODE16, io_base, io_base, 1, ACPI_GPE_PROC_LEN) 257 ); 258 aml_append(dev, aml_name_decl("_CRS", crs)); 259 aml_append(sb_scope, dev); 260 /* declare CPU hotplug MMIO region and PRS field to access it */ 261 aml_append(sb_scope, aml_operation_region( 262 "PRST", AML_SYSTEM_IO, aml_int(io_base), ACPI_GPE_PROC_LEN)); 263 field = aml_field("PRST", AML_BYTE_ACC, AML_NOLOCK, AML_PRESERVE); 264 aml_append(field, aml_named_field("PRS", 256)); 265 aml_append(sb_scope, field); 266 267 /* build Processor object for each processor */ 268 for (i = 0; i < apic_ids->len; i++) { 269 int apic_id = apic_ids->cpus[i].arch_id; 270 271 assert(apic_id < ACPI_CPU_HOTPLUG_ID_LIMIT); 272 273 dev = aml_processor(i, 0, 0, "CP%.02X", apic_id); 274 275 method = aml_method("_MAT", 0, AML_NOTSERIALIZED); 276 aml_append(method, 277 aml_return(aml_call2(CPU_MAT_METHOD, aml_int(apic_id), aml_int(i)) 278 )); 279 aml_append(dev, method); 280 281 method = aml_method("_STA", 0, AML_NOTSERIALIZED); 282 aml_append(method, 283 aml_return(aml_call1(CPU_STATUS_METHOD, aml_int(apic_id)))); 284 aml_append(dev, method); 285 286 method = aml_method("_EJ0", 1, AML_NOTSERIALIZED); 287 aml_append(method, 288 aml_return(aml_call2(CPU_EJECT_METHOD, aml_int(apic_id), 289 aml_arg(0))) 290 ); 291 aml_append(dev, method); 292 293 aml_append(sb_scope, dev); 294 } 295 296 /* build this code: 297 * Method(NTFY, 2) {If (LEqual(Arg0, 0x00)) {Notify(CP00, Arg1)} ...} 298 */ 299 /* Arg0 = APIC ID */ 300 method = aml_method(AML_NOTIFY_METHOD, 2, AML_NOTSERIALIZED); 301 for (i = 0; i < apic_ids->len; i++) { 302 int apic_id = apic_ids->cpus[i].arch_id; 303 304 if_ctx = aml_if(aml_equal(aml_arg(0), aml_int(apic_id))); 305 aml_append(if_ctx, 306 aml_notify(aml_name("CP%.02X", apic_id), aml_arg(1)) 307 ); 308 aml_append(method, if_ctx); 309 } 310 aml_append(sb_scope, method); 311 312 /* build "Name(CPON, Package() { One, One, ..., Zero, Zero, ... })" 313 * 314 * Note: The ability to create variable-sized packages was first 315 * introduced in ACPI 2.0. ACPI 1.0 only allowed fixed-size packages 316 * ith up to 255 elements. Windows guests up to win2k8 fail when 317 * VarPackageOp is used. 318 */ 319 pkg = pcms->apic_id_limit <= 255 ? aml_package(pcms->apic_id_limit) : 320 aml_varpackage(pcms->apic_id_limit); 321 322 for (i = 0, apic_idx = 0; i < apic_ids->len; i++) { 323 int apic_id = apic_ids->cpus[i].arch_id; 324 325 for (; apic_idx < apic_id; apic_idx++) { 326 aml_append(pkg, aml_int(0)); 327 } 328 aml_append(pkg, aml_int(apic_ids->cpus[i].cpu ? 1 : 0)); 329 apic_idx = apic_id + 1; 330 } 331 aml_append(sb_scope, aml_name_decl(CPU_ON_BITMAP, pkg)); 332 aml_append(ctx, sb_scope); 333 334 method = aml_method("\\_GPE._E02", 0, AML_NOTSERIALIZED); 335 aml_append(method, aml_call0("\\_SB." CPU_SCAN_METHOD)); 336 aml_append(ctx, method); 337 } 338