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