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/pc.h" 17 #include "hw/pci/pci.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 { 64 CPUClass *k = CPU_GET_CLASS(cpu); 65 int64_t cpu_id; 66 67 cpu_id = k->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 return; 72 } 73 74 g->sts[cpu_id / 8] |= (1 << (cpu_id % 8)); 75 } 76 77 void legacy_acpi_cpu_plug_cb(HotplugHandler *hotplug_dev, 78 AcpiCpuHotplug *g, DeviceState *dev, Error **errp) 79 { 80 acpi_set_cpu_present_bit(g, CPU(dev)); 81 acpi_send_event(DEVICE(hotplug_dev), ACPI_CPU_HOTPLUG_STATUS); 82 } 83 84 void legacy_acpi_cpu_hotplug_init(MemoryRegion *parent, Object *owner, 85 AcpiCpuHotplug *gpe_cpu, uint16_t base) 86 { 87 CPUState *cpu; 88 89 memory_region_init_io(&gpe_cpu->io, owner, &AcpiCpuHotplug_ops, 90 gpe_cpu, "acpi-cpu-hotplug", ACPI_GPE_PROC_LEN); 91 memory_region_add_subregion(parent, base, &gpe_cpu->io); 92 gpe_cpu->device = owner; 93 94 CPU_FOREACH(cpu) { 95 acpi_set_cpu_present_bit(gpe_cpu, cpu); 96 } 97 } 98 99 void acpi_switch_to_modern_cphp(AcpiCpuHotplug *gpe_cpu, 100 CPUHotplugState *cpuhp_state, 101 uint16_t io_port) 102 { 103 MemoryRegion *parent = pci_address_space_io(PCI_DEVICE(gpe_cpu->device)); 104 105 memory_region_del_subregion(parent, &gpe_cpu->io); 106 cpu_hotplug_hw_init(parent, gpe_cpu->device, cpuhp_state, io_port); 107 } 108 109 void build_legacy_cpu_hotplug_aml(Aml *ctx, MachineState *machine, 110 uint16_t io_base) 111 { 112 Aml *dev; 113 Aml *crs; 114 Aml *pkg; 115 Aml *field; 116 Aml *method; 117 Aml *if_ctx; 118 Aml *else_ctx; 119 int i, apic_idx; 120 Aml *sb_scope = aml_scope("_SB"); 121 uint8_t madt_tmpl[8] = {0x00, 0x08, 0x00, 0x00, 0x00, 0, 0, 0}; 122 Aml *cpu_id = aml_arg(1); 123 Aml *apic_id = aml_arg(0); 124 Aml *cpu_on = aml_local(0); 125 Aml *madt = aml_local(1); 126 Aml *cpus_map = aml_name(CPU_ON_BITMAP); 127 Aml *zero = aml_int(0); 128 Aml *one = aml_int(1); 129 MachineClass *mc = MACHINE_GET_CLASS(machine); 130 const CPUArchIdList *apic_ids = mc->possible_cpu_arch_ids(machine); 131 X86MachineState *x86ms = X86_MACHINE(machine); 132 133 /* 134 * _MAT method - creates an madt apic buffer 135 * apic_id = Arg0 = Local APIC ID 136 * cpu_id = Arg1 = Processor ID 137 * cpu_on = Local0 = CPON flag for this cpu 138 * madt = Local1 = Buffer (in madt apic form) to return 139 */ 140 method = aml_method(CPU_MAT_METHOD, 2, AML_NOTSERIALIZED); 141 aml_append(method, 142 aml_store(aml_derefof(aml_index(cpus_map, apic_id)), cpu_on)); 143 aml_append(method, 144 aml_store(aml_buffer(sizeof(madt_tmpl), madt_tmpl), madt)); 145 /* Update the processor id, lapic id, and enable/disable status */ 146 aml_append(method, aml_store(cpu_id, aml_index(madt, aml_int(2)))); 147 aml_append(method, aml_store(apic_id, aml_index(madt, aml_int(3)))); 148 aml_append(method, aml_store(cpu_on, aml_index(madt, aml_int(4)))); 149 aml_append(method, aml_return(madt)); 150 aml_append(sb_scope, method); 151 152 /* 153 * _STA method - return ON status of cpu 154 * apic_id = Arg0 = Local APIC ID 155 * cpu_on = Local0 = CPON flag for this cpu 156 */ 157 method = aml_method(CPU_STATUS_METHOD, 1, AML_NOTSERIALIZED); 158 aml_append(method, 159 aml_store(aml_derefof(aml_index(cpus_map, apic_id)), cpu_on)); 160 if_ctx = aml_if(cpu_on); 161 { 162 aml_append(if_ctx, aml_return(aml_int(0xF))); 163 } 164 aml_append(method, if_ctx); 165 else_ctx = aml_else(); 166 { 167 aml_append(else_ctx, aml_return(zero)); 168 } 169 aml_append(method, else_ctx); 170 aml_append(sb_scope, method); 171 172 method = aml_method(CPU_EJECT_METHOD, 2, AML_NOTSERIALIZED); 173 aml_append(method, aml_sleep(200)); 174 aml_append(sb_scope, method); 175 176 method = aml_method(CPU_SCAN_METHOD, 0, AML_NOTSERIALIZED); 177 { 178 Aml *while_ctx, *if_ctx2, *else_ctx2; 179 Aml *bus_check_evt = aml_int(1); 180 Aml *remove_evt = aml_int(3); 181 Aml *status_map = aml_local(5); /* Local5 = active cpu bitmap */ 182 Aml *byte = aml_local(2); /* Local2 = last read byte from bitmap */ 183 Aml *idx = aml_local(0); /* Processor ID / APIC ID iterator */ 184 Aml *is_cpu_on = aml_local(1); /* Local1 = CPON flag for cpu */ 185 Aml *status = aml_local(3); /* Local3 = active state for cpu */ 186 187 aml_append(method, aml_store(aml_name(CPU_STATUS_MAP), status_map)); 188 aml_append(method, aml_store(zero, byte)); 189 aml_append(method, aml_store(zero, idx)); 190 191 /* While (idx < SizeOf(CPON)) */ 192 while_ctx = aml_while(aml_lless(idx, aml_sizeof(cpus_map))); 193 aml_append(while_ctx, 194 aml_store(aml_derefof(aml_index(cpus_map, idx)), is_cpu_on)); 195 196 if_ctx = aml_if(aml_and(idx, aml_int(0x07), NULL)); 197 { 198 /* Shift down previously read bitmap byte */ 199 aml_append(if_ctx, aml_shiftright(byte, one, byte)); 200 } 201 aml_append(while_ctx, if_ctx); 202 203 else_ctx = aml_else(); 204 { 205 /* Read next byte from cpu bitmap */ 206 aml_append(else_ctx, aml_store(aml_derefof(aml_index(status_map, 207 aml_shiftright(idx, aml_int(3), NULL))), byte)); 208 } 209 aml_append(while_ctx, else_ctx); 210 211 aml_append(while_ctx, aml_store(aml_and(byte, one, NULL), status)); 212 if_ctx = aml_if(aml_lnot(aml_equal(is_cpu_on, status))); 213 { 214 /* State change - update CPON with new state */ 215 aml_append(if_ctx, aml_store(status, aml_index(cpus_map, idx))); 216 if_ctx2 = aml_if(aml_equal(status, one)); 217 { 218 aml_append(if_ctx2, 219 aml_call2(AML_NOTIFY_METHOD, idx, bus_check_evt)); 220 } 221 aml_append(if_ctx, if_ctx2); 222 else_ctx2 = aml_else(); 223 { 224 aml_append(else_ctx2, 225 aml_call2(AML_NOTIFY_METHOD, idx, remove_evt)); 226 } 227 } 228 aml_append(if_ctx, else_ctx2); 229 aml_append(while_ctx, if_ctx); 230 231 aml_append(while_ctx, aml_increment(idx)); /* go to next cpu */ 232 aml_append(method, while_ctx); 233 } 234 aml_append(sb_scope, method); 235 236 /* The current AML generator can cover the APIC ID range [0..255], 237 * inclusive, for VCPU hotplug. */ 238 QEMU_BUILD_BUG_ON(ACPI_CPU_HOTPLUG_ID_LIMIT > 256); 239 if (x86ms->apic_id_limit > ACPI_CPU_HOTPLUG_ID_LIMIT) { 240 error_report("max_cpus is too large. APIC ID of last CPU is %u", 241 x86ms->apic_id_limit - 1); 242 exit(1); 243 } 244 245 /* create PCI0.PRES device and its _CRS to reserve CPU hotplug MMIO */ 246 dev = aml_device("PCI0." stringify(CPU_HOTPLUG_RESOURCE_DEVICE)); 247 aml_append(dev, aml_name_decl("_HID", aml_eisaid("PNP0A06"))); 248 aml_append(dev, 249 aml_name_decl("_UID", aml_string("CPU Hotplug resources")) 250 ); 251 /* device present, functioning, decoding, not shown in UI */ 252 aml_append(dev, aml_name_decl("_STA", aml_int(0xB))); 253 crs = aml_resource_template(); 254 aml_append(crs, 255 aml_io(AML_DECODE16, io_base, io_base, 1, ACPI_GPE_PROC_LEN) 256 ); 257 aml_append(dev, aml_name_decl("_CRS", crs)); 258 aml_append(sb_scope, dev); 259 /* declare CPU hotplug MMIO region and PRS field to access it */ 260 aml_append(sb_scope, aml_operation_region( 261 "PRST", AML_SYSTEM_IO, aml_int(io_base), ACPI_GPE_PROC_LEN)); 262 field = aml_field("PRST", AML_BYTE_ACC, AML_NOLOCK, AML_PRESERVE); 263 aml_append(field, aml_named_field("PRS", 256)); 264 aml_append(sb_scope, field); 265 266 /* build Processor object for each processor */ 267 for (i = 0; i < apic_ids->len; i++) { 268 int cpu_apic_id = apic_ids->cpus[i].arch_id; 269 270 assert(cpu_apic_id < ACPI_CPU_HOTPLUG_ID_LIMIT); 271 272 dev = aml_processor(i, 0, 0, "CP%.02X", cpu_apic_id); 273 274 method = aml_method("_MAT", 0, AML_NOTSERIALIZED); 275 aml_append(method, 276 aml_return(aml_call2(CPU_MAT_METHOD, 277 aml_int(cpu_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(cpu_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(cpu_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 cpu_apic_id = apic_ids->cpus[i].arch_id; 303 304 if_ctx = aml_if(aml_equal(aml_arg(0), aml_int(cpu_apic_id))); 305 aml_append(if_ctx, 306 aml_notify(aml_name("CP%.02X", cpu_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 = x86ms->apic_id_limit <= 255 ? aml_package(x86ms->apic_id_limit) : 320 aml_varpackage(x86ms->apic_id_limit); 321 322 for (i = 0, apic_idx = 0; i < apic_ids->len; i++) { 323 int cpu_apic_id = apic_ids->cpus[i].arch_id; 324 325 for (; apic_idx < cpu_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 = cpu_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