xref: /openbmc/qemu/hw/acpi/cpu.c (revision efdb43b8)
1 #include "qemu/osdep.h"
2 #include "migration/vmstate.h"
3 #include "hw/acpi/cpu.h"
4 #include "hw/core/cpu.h"
5 #include "qapi/error.h"
6 #include "qapi/qapi-events-acpi.h"
7 #include "trace.h"
8 #include "sysemu/numa.h"
9 
10 #define ACPI_CPU_SELECTOR_OFFSET_WR 0
11 #define ACPI_CPU_FLAGS_OFFSET_RW 4
12 #define ACPI_CPU_CMD_OFFSET_WR 5
13 #define ACPI_CPU_CMD_DATA_OFFSET_RW 8
14 #define ACPI_CPU_CMD_DATA2_OFFSET_R 0
15 
16 #define OVMF_CPUHP_SMI_CMD 4
17 
18 enum {
19     CPHP_GET_NEXT_CPU_WITH_EVENT_CMD = 0,
20     CPHP_OST_EVENT_CMD = 1,
21     CPHP_OST_STATUS_CMD = 2,
22     CPHP_GET_CPU_ID_CMD = 3,
23     CPHP_CMD_MAX
24 };
25 
acpi_cpu_device_status(int idx,AcpiCpuStatus * cdev)26 static ACPIOSTInfo *acpi_cpu_device_status(int idx, AcpiCpuStatus *cdev)
27 {
28     ACPIOSTInfo *info = g_new0(ACPIOSTInfo, 1);
29 
30     info->slot_type = ACPI_SLOT_TYPE_CPU;
31     info->slot = g_strdup_printf("%d", idx);
32     info->source = cdev->ost_event;
33     info->status = cdev->ost_status;
34     if (cdev->cpu) {
35         DeviceState *dev = DEVICE(cdev->cpu);
36         if (dev->id) {
37             info->device = g_strdup(dev->id);
38         }
39     }
40     return info;
41 }
42 
acpi_cpu_ospm_status(CPUHotplugState * cpu_st,ACPIOSTInfoList *** list)43 void acpi_cpu_ospm_status(CPUHotplugState *cpu_st, ACPIOSTInfoList ***list)
44 {
45     ACPIOSTInfoList ***tail = list;
46     int i;
47 
48     for (i = 0; i < cpu_st->dev_count; i++) {
49         QAPI_LIST_APPEND(*tail, acpi_cpu_device_status(i, &cpu_st->devs[i]));
50     }
51 }
52 
cpu_hotplug_rd(void * opaque,hwaddr addr,unsigned size)53 static uint64_t cpu_hotplug_rd(void *opaque, hwaddr addr, unsigned size)
54 {
55     uint64_t val = 0;
56     CPUHotplugState *cpu_st = opaque;
57     AcpiCpuStatus *cdev;
58 
59     if (cpu_st->selector >= cpu_st->dev_count) {
60         return val;
61     }
62 
63     cdev = &cpu_st->devs[cpu_st->selector];
64     switch (addr) {
65     case ACPI_CPU_FLAGS_OFFSET_RW: /* pack and return is_* fields */
66         val |= cdev->cpu ? 1 : 0;
67         val |= cdev->is_inserting ? 2 : 0;
68         val |= cdev->is_removing  ? 4 : 0;
69         val |= cdev->fw_remove  ? 16 : 0;
70         trace_cpuhp_acpi_read_flags(cpu_st->selector, val);
71         break;
72     case ACPI_CPU_CMD_DATA_OFFSET_RW:
73         switch (cpu_st->command) {
74         case CPHP_GET_NEXT_CPU_WITH_EVENT_CMD:
75            val = cpu_st->selector;
76            break;
77         case CPHP_GET_CPU_ID_CMD:
78            val = cdev->arch_id & 0xFFFFFFFF;
79            break;
80         default:
81            break;
82         }
83         trace_cpuhp_acpi_read_cmd_data(cpu_st->selector, val);
84         break;
85     case ACPI_CPU_CMD_DATA2_OFFSET_R:
86         switch (cpu_st->command) {
87         case CPHP_GET_NEXT_CPU_WITH_EVENT_CMD:
88            val = 0;
89            break;
90         case CPHP_GET_CPU_ID_CMD:
91            val = cdev->arch_id >> 32;
92            break;
93         default:
94            break;
95         }
96         trace_cpuhp_acpi_read_cmd_data2(cpu_st->selector, val);
97         break;
98     default:
99         break;
100     }
101     return val;
102 }
103 
cpu_hotplug_wr(void * opaque,hwaddr addr,uint64_t data,unsigned int size)104 static void cpu_hotplug_wr(void *opaque, hwaddr addr, uint64_t data,
105                            unsigned int size)
106 {
107     CPUHotplugState *cpu_st = opaque;
108     AcpiCpuStatus *cdev;
109     ACPIOSTInfo *info;
110 
111     assert(cpu_st->dev_count);
112 
113     if (addr) {
114         if (cpu_st->selector >= cpu_st->dev_count) {
115             trace_cpuhp_acpi_invalid_idx_selected(cpu_st->selector);
116             return;
117         }
118     }
119 
120     switch (addr) {
121     case ACPI_CPU_SELECTOR_OFFSET_WR: /* current CPU selector */
122         cpu_st->selector = data;
123         trace_cpuhp_acpi_write_idx(cpu_st->selector);
124         break;
125     case ACPI_CPU_FLAGS_OFFSET_RW: /* set is_* fields  */
126         cdev = &cpu_st->devs[cpu_st->selector];
127         if (data & 2) { /* clear insert event */
128             cdev->is_inserting = false;
129             trace_cpuhp_acpi_clear_inserting_evt(cpu_st->selector);
130         } else if (data & 4) { /* clear remove event */
131             cdev->is_removing = false;
132             trace_cpuhp_acpi_clear_remove_evt(cpu_st->selector);
133         } else if (data & 8) {
134             DeviceState *dev = NULL;
135             HotplugHandler *hotplug_ctrl = NULL;
136 
137             if (!cdev->cpu || cdev->cpu == first_cpu) {
138                 trace_cpuhp_acpi_ejecting_invalid_cpu(cpu_st->selector);
139                 break;
140             }
141 
142             trace_cpuhp_acpi_ejecting_cpu(cpu_st->selector);
143             dev = DEVICE(cdev->cpu);
144             hotplug_ctrl = qdev_get_hotplug_handler(dev);
145             hotplug_handler_unplug(hotplug_ctrl, dev, NULL);
146             object_unparent(OBJECT(dev));
147             cdev->fw_remove = false;
148         } else if (data & 16) {
149             if (!cdev->cpu || cdev->cpu == first_cpu) {
150                 trace_cpuhp_acpi_fw_remove_invalid_cpu(cpu_st->selector);
151                 break;
152             }
153             trace_cpuhp_acpi_fw_remove_cpu(cpu_st->selector);
154             cdev->fw_remove = true;
155         }
156         break;
157     case ACPI_CPU_CMD_OFFSET_WR:
158         trace_cpuhp_acpi_write_cmd(cpu_st->selector, data);
159         if (data < CPHP_CMD_MAX) {
160             cpu_st->command = data;
161             if (cpu_st->command == CPHP_GET_NEXT_CPU_WITH_EVENT_CMD) {
162                 uint32_t iter = cpu_st->selector;
163 
164                 do {
165                     cdev = &cpu_st->devs[iter];
166                     if (cdev->is_inserting || cdev->is_removing ||
167                         cdev->fw_remove) {
168                         cpu_st->selector = iter;
169                         trace_cpuhp_acpi_cpu_has_events(cpu_st->selector,
170                             cdev->is_inserting, cdev->is_removing);
171                         break;
172                     }
173                     iter = iter + 1 < cpu_st->dev_count ? iter + 1 : 0;
174                 } while (iter != cpu_st->selector);
175             }
176         }
177         break;
178     case ACPI_CPU_CMD_DATA_OFFSET_RW:
179         switch (cpu_st->command) {
180         case CPHP_OST_EVENT_CMD: {
181            cdev = &cpu_st->devs[cpu_st->selector];
182            cdev->ost_event = data;
183            trace_cpuhp_acpi_write_ost_ev(cpu_st->selector, cdev->ost_event);
184            break;
185         }
186         case CPHP_OST_STATUS_CMD: {
187            cdev = &cpu_st->devs[cpu_st->selector];
188            cdev->ost_status = data;
189            info = acpi_cpu_device_status(cpu_st->selector, cdev);
190            qapi_event_send_acpi_device_ost(info);
191            qapi_free_ACPIOSTInfo(info);
192            trace_cpuhp_acpi_write_ost_status(cpu_st->selector,
193                                              cdev->ost_status);
194            break;
195         }
196         default:
197            break;
198         }
199         break;
200     default:
201         break;
202     }
203 }
204 
205 static const MemoryRegionOps cpu_hotplug_ops = {
206     .read = cpu_hotplug_rd,
207     .write = cpu_hotplug_wr,
208     .endianness = DEVICE_LITTLE_ENDIAN,
209     .valid = {
210         .min_access_size = 1,
211         .max_access_size = 4,
212     },
213 };
214 
cpu_hotplug_hw_init(MemoryRegion * as,Object * owner,CPUHotplugState * state,hwaddr base_addr)215 void cpu_hotplug_hw_init(MemoryRegion *as, Object *owner,
216                          CPUHotplugState *state, hwaddr base_addr)
217 {
218     MachineState *machine = MACHINE(qdev_get_machine());
219     MachineClass *mc = MACHINE_GET_CLASS(machine);
220     const CPUArchIdList *id_list;
221     int i;
222 
223     assert(mc->possible_cpu_arch_ids);
224     id_list = mc->possible_cpu_arch_ids(machine);
225     state->dev_count = id_list->len;
226     state->devs = g_new0(typeof(*state->devs), state->dev_count);
227     for (i = 0; i < id_list->len; i++) {
228         state->devs[i].cpu =  CPU(id_list->cpus[i].cpu);
229         state->devs[i].arch_id = id_list->cpus[i].arch_id;
230     }
231     memory_region_init_io(&state->ctrl_reg, owner, &cpu_hotplug_ops, state,
232                           "acpi-cpu-hotplug", ACPI_CPU_HOTPLUG_REG_LEN);
233     memory_region_add_subregion(as, base_addr, &state->ctrl_reg);
234 }
235 
get_cpu_status(CPUHotplugState * cpu_st,DeviceState * dev)236 static AcpiCpuStatus *get_cpu_status(CPUHotplugState *cpu_st, DeviceState *dev)
237 {
238     CPUClass *k = CPU_GET_CLASS(dev);
239     uint64_t cpu_arch_id = k->get_arch_id(CPU(dev));
240     int i;
241 
242     for (i = 0; i < cpu_st->dev_count; i++) {
243         if (cpu_arch_id == cpu_st->devs[i].arch_id) {
244             return &cpu_st->devs[i];
245         }
246     }
247     return NULL;
248 }
249 
acpi_cpu_plug_cb(HotplugHandler * hotplug_dev,CPUHotplugState * cpu_st,DeviceState * dev,Error ** errp)250 void acpi_cpu_plug_cb(HotplugHandler *hotplug_dev,
251                       CPUHotplugState *cpu_st, DeviceState *dev, Error **errp)
252 {
253     AcpiCpuStatus *cdev;
254 
255     cdev = get_cpu_status(cpu_st, dev);
256     if (!cdev) {
257         return;
258     }
259 
260     cdev->cpu = CPU(dev);
261     if (dev->hotplugged) {
262         cdev->is_inserting = true;
263         acpi_send_event(DEVICE(hotplug_dev), ACPI_CPU_HOTPLUG_STATUS);
264     }
265 }
266 
acpi_cpu_unplug_request_cb(HotplugHandler * hotplug_dev,CPUHotplugState * cpu_st,DeviceState * dev,Error ** errp)267 void acpi_cpu_unplug_request_cb(HotplugHandler *hotplug_dev,
268                                 CPUHotplugState *cpu_st,
269                                 DeviceState *dev, Error **errp)
270 {
271     AcpiCpuStatus *cdev;
272 
273     cdev = get_cpu_status(cpu_st, dev);
274     if (!cdev) {
275         return;
276     }
277 
278     cdev->is_removing = true;
279     acpi_send_event(DEVICE(hotplug_dev), ACPI_CPU_HOTPLUG_STATUS);
280 }
281 
acpi_cpu_unplug_cb(CPUHotplugState * cpu_st,DeviceState * dev,Error ** errp)282 void acpi_cpu_unplug_cb(CPUHotplugState *cpu_st,
283                         DeviceState *dev, Error **errp)
284 {
285     AcpiCpuStatus *cdev;
286 
287     cdev = get_cpu_status(cpu_st, dev);
288     if (!cdev) {
289         return;
290     }
291 
292     cdev->cpu = NULL;
293 }
294 
295 static const VMStateDescription vmstate_cpuhp_sts = {
296     .name = "CPU hotplug device state",
297     .version_id = 1,
298     .minimum_version_id = 1,
299     .fields = (const VMStateField[]) {
300         VMSTATE_BOOL(is_inserting, AcpiCpuStatus),
301         VMSTATE_BOOL(is_removing, AcpiCpuStatus),
302         VMSTATE_UINT32(ost_event, AcpiCpuStatus),
303         VMSTATE_UINT32(ost_status, AcpiCpuStatus),
304         VMSTATE_END_OF_LIST()
305     }
306 };
307 
308 const VMStateDescription vmstate_cpu_hotplug = {
309     .name = "CPU hotplug state",
310     .version_id = 1,
311     .minimum_version_id = 1,
312     .fields = (const VMStateField[]) {
313         VMSTATE_UINT32(selector, CPUHotplugState),
314         VMSTATE_UINT8(command, CPUHotplugState),
315         VMSTATE_STRUCT_VARRAY_POINTER_UINT32(devs, CPUHotplugState, dev_count,
316                                              vmstate_cpuhp_sts, AcpiCpuStatus),
317         VMSTATE_END_OF_LIST()
318     }
319 };
320 
321 #define CPU_NAME_FMT      "C%.03X"
322 #define CPUHP_RES_DEVICE  "PRES"
323 #define CPU_LOCK          "CPLK"
324 #define CPU_STS_METHOD    "CSTA"
325 #define CPU_SCAN_METHOD   "CSCN"
326 #define CPU_NOTIFY_METHOD "CTFY"
327 #define CPU_EJECT_METHOD  "CEJ0"
328 #define CPU_OST_METHOD    "COST"
329 #define CPU_ADDED_LIST    "CNEW"
330 
331 #define CPU_ENABLED       "CPEN"
332 #define CPU_SELECTOR      "CSEL"
333 #define CPU_COMMAND       "CCMD"
334 #define CPU_DATA          "CDAT"
335 #define CPU_INSERT_EVENT  "CINS"
336 #define CPU_REMOVE_EVENT  "CRMV"
337 #define CPU_EJECT_EVENT   "CEJ0"
338 #define CPU_FW_EJECT_EVENT "CEJF"
339 
build_cpus_aml(Aml * table,MachineState * machine,CPUHotplugFeatures opts,build_madt_cpu_fn build_madt_cpu,hwaddr base_addr,const char * res_root,const char * event_handler_method,AmlRegionSpace rs)340 void build_cpus_aml(Aml *table, MachineState *machine, CPUHotplugFeatures opts,
341                     build_madt_cpu_fn build_madt_cpu, hwaddr base_addr,
342                     const char *res_root,
343                     const char *event_handler_method,
344                     AmlRegionSpace rs)
345 {
346     Aml *ifctx;
347     Aml *field;
348     Aml *method;
349     Aml *cpu_ctrl_dev;
350     Aml *cpus_dev;
351     Aml *zero = aml_int(0);
352     Aml *one = aml_int(1);
353     Aml *sb_scope = aml_scope("_SB");
354     MachineClass *mc = MACHINE_GET_CLASS(machine);
355     const CPUArchIdList *arch_ids = mc->possible_cpu_arch_ids(machine);
356     char *cphp_res_path = g_strdup_printf("%s." CPUHP_RES_DEVICE, res_root);
357 
358     cpu_ctrl_dev = aml_device("%s", cphp_res_path);
359     {
360         Aml *crs;
361 
362         aml_append(cpu_ctrl_dev,
363             aml_name_decl("_HID", aml_eisaid("PNP0A06")));
364         aml_append(cpu_ctrl_dev,
365             aml_name_decl("_UID", aml_string("CPU Hotplug resources")));
366         aml_append(cpu_ctrl_dev, aml_mutex(CPU_LOCK, 0));
367 
368         assert((rs == AML_SYSTEM_IO) || (rs == AML_SYSTEM_MEMORY));
369 
370         crs = aml_resource_template();
371         if (rs == AML_SYSTEM_IO) {
372             aml_append(crs, aml_io(AML_DECODE16, base_addr, base_addr, 1,
373                                ACPI_CPU_HOTPLUG_REG_LEN));
374         } else if (rs == AML_SYSTEM_MEMORY) {
375             aml_append(crs, aml_memory32_fixed(base_addr,
376                                ACPI_CPU_HOTPLUG_REG_LEN, AML_READ_WRITE));
377         }
378 
379         aml_append(cpu_ctrl_dev, aml_name_decl("_CRS", crs));
380 
381         /* declare CPU hotplug MMIO region with related access fields */
382         aml_append(cpu_ctrl_dev,
383             aml_operation_region("PRST", rs, aml_int(base_addr),
384                                  ACPI_CPU_HOTPLUG_REG_LEN));
385 
386         field = aml_field("PRST", AML_BYTE_ACC, AML_NOLOCK,
387                           AML_WRITE_AS_ZEROS);
388         aml_append(field, aml_reserved_field(ACPI_CPU_FLAGS_OFFSET_RW * 8));
389         /* 1 if enabled, read only */
390         aml_append(field, aml_named_field(CPU_ENABLED, 1));
391         /* (read) 1 if has a insert event. (write) 1 to clear event */
392         aml_append(field, aml_named_field(CPU_INSERT_EVENT, 1));
393         /* (read) 1 if has a remove event. (write) 1 to clear event */
394         aml_append(field, aml_named_field(CPU_REMOVE_EVENT, 1));
395         /* initiates device eject, write only */
396         aml_append(field, aml_named_field(CPU_EJECT_EVENT, 1));
397         /* tell firmware to do device eject, write only */
398         aml_append(field, aml_named_field(CPU_FW_EJECT_EVENT, 1));
399         aml_append(field, aml_reserved_field(3));
400         aml_append(field, aml_named_field(CPU_COMMAND, 8));
401         aml_append(cpu_ctrl_dev, field);
402 
403         field = aml_field("PRST", AML_DWORD_ACC, AML_NOLOCK, AML_PRESERVE);
404         /* CPU selector, write only */
405         aml_append(field, aml_named_field(CPU_SELECTOR, 32));
406         /* flags + cmd + 2byte align */
407         aml_append(field, aml_reserved_field(4 * 8));
408         aml_append(field, aml_named_field(CPU_DATA, 32));
409         aml_append(cpu_ctrl_dev, field);
410 
411         if (opts.has_legacy_cphp) {
412             method = aml_method("_INI", 0, AML_SERIALIZED);
413             /* switch off legacy CPU hotplug HW and use new one,
414              * on reboot system is in new mode and writing 0
415              * in CPU_SELECTOR selects BSP, which is NOP at
416              * the time _INI is called */
417             aml_append(method, aml_store(zero, aml_name(CPU_SELECTOR)));
418             aml_append(cpu_ctrl_dev, method);
419         }
420     }
421     aml_append(sb_scope, cpu_ctrl_dev);
422 
423     cpus_dev = aml_device("\\_SB.CPUS");
424     {
425         int i;
426         Aml *ctrl_lock = aml_name("%s.%s", cphp_res_path, CPU_LOCK);
427         Aml *cpu_selector = aml_name("%s.%s", cphp_res_path, CPU_SELECTOR);
428         Aml *is_enabled = aml_name("%s.%s", cphp_res_path, CPU_ENABLED);
429         Aml *cpu_cmd = aml_name("%s.%s", cphp_res_path, CPU_COMMAND);
430         Aml *cpu_data = aml_name("%s.%s", cphp_res_path, CPU_DATA);
431         Aml *ins_evt = aml_name("%s.%s", cphp_res_path, CPU_INSERT_EVENT);
432         Aml *rm_evt = aml_name("%s.%s", cphp_res_path, CPU_REMOVE_EVENT);
433         Aml *ej_evt = aml_name("%s.%s", cphp_res_path, CPU_EJECT_EVENT);
434         Aml *fw_ej_evt = aml_name("%s.%s", cphp_res_path, CPU_FW_EJECT_EVENT);
435 
436         aml_append(cpus_dev, aml_name_decl("_HID", aml_string("ACPI0010")));
437         aml_append(cpus_dev, aml_name_decl("_CID", aml_eisaid("PNP0A05")));
438 
439         method = aml_method(CPU_NOTIFY_METHOD, 2, AML_NOTSERIALIZED);
440         for (i = 0; i < arch_ids->len; i++) {
441             Aml *cpu = aml_name(CPU_NAME_FMT, i);
442             Aml *uid = aml_arg(0);
443             Aml *event = aml_arg(1);
444 
445             ifctx = aml_if(aml_equal(uid, aml_int(i)));
446             {
447                 aml_append(ifctx, aml_notify(cpu, event));
448             }
449             aml_append(method, ifctx);
450         }
451         aml_append(cpus_dev, method);
452 
453         method = aml_method(CPU_STS_METHOD, 1, AML_SERIALIZED);
454         {
455             Aml *idx = aml_arg(0);
456             Aml *sta = aml_local(0);
457 
458             aml_append(method, aml_acquire(ctrl_lock, 0xFFFF));
459             aml_append(method, aml_store(idx, cpu_selector));
460             aml_append(method, aml_store(zero, sta));
461             ifctx = aml_if(aml_equal(is_enabled, one));
462             {
463                 aml_append(ifctx, aml_store(aml_int(0xF), sta));
464             }
465             aml_append(method, ifctx);
466             aml_append(method, aml_release(ctrl_lock));
467             aml_append(method, aml_return(sta));
468         }
469         aml_append(cpus_dev, method);
470 
471         method = aml_method(CPU_EJECT_METHOD, 1, AML_SERIALIZED);
472         {
473             Aml *idx = aml_arg(0);
474 
475             aml_append(method, aml_acquire(ctrl_lock, 0xFFFF));
476             aml_append(method, aml_store(idx, cpu_selector));
477             if (opts.fw_unplugs_cpu) {
478                 aml_append(method, aml_store(one, fw_ej_evt));
479                 aml_append(method, aml_store(aml_int(OVMF_CPUHP_SMI_CMD),
480                            aml_name("%s", opts.smi_path)));
481             } else {
482                 aml_append(method, aml_store(one, ej_evt));
483             }
484             aml_append(method, aml_release(ctrl_lock));
485         }
486         aml_append(cpus_dev, method);
487 
488         method = aml_method(CPU_SCAN_METHOD, 0, AML_SERIALIZED);
489         {
490             const uint8_t max_cpus_per_pass = 255;
491             Aml *else_ctx;
492             Aml *while_ctx, *while_ctx2;
493             Aml *has_event = aml_local(0);
494             Aml *dev_chk = aml_int(1);
495             Aml *eject_req = aml_int(3);
496             Aml *next_cpu_cmd = aml_int(CPHP_GET_NEXT_CPU_WITH_EVENT_CMD);
497             Aml *num_added_cpus = aml_local(1);
498             Aml *cpu_idx = aml_local(2);
499             Aml *uid = aml_local(3);
500             Aml *has_job = aml_local(4);
501             Aml *new_cpus = aml_name(CPU_ADDED_LIST);
502 
503             aml_append(method, aml_acquire(ctrl_lock, 0xFFFF));
504 
505             /*
506              * Windows versions newer than XP (including Windows 10/Windows
507              * Server 2019), do support* VarPackageOp but, it is cripled to hold
508              * the same elements number as old PackageOp.
509              * For compatibility with Windows XP (so it won't crash) use ACPI1.0
510              * PackageOp which can hold max 255 elements.
511              *
512              * use named package as old Windows don't support it in local var
513              */
514             aml_append(method, aml_name_decl(CPU_ADDED_LIST,
515                                              aml_package(max_cpus_per_pass)));
516 
517             aml_append(method, aml_store(zero, uid));
518             aml_append(method, aml_store(one, has_job));
519             /*
520              * CPU_ADDED_LIST can hold limited number of elements, outer loop
521              * allows to process CPUs in batches which let us to handle more
522              * CPUs than CPU_ADDED_LIST can hold.
523              */
524             while_ctx2 = aml_while(aml_equal(has_job, one));
525             {
526                 aml_append(while_ctx2, aml_store(zero, has_job));
527 
528                 aml_append(while_ctx2, aml_store(one, has_event));
529                 aml_append(while_ctx2, aml_store(zero, num_added_cpus));
530 
531                 /*
532                  * Scan CPUs, till there are CPUs with events or
533                  * CPU_ADDED_LIST capacity is exhausted
534                  */
535                 while_ctx = aml_while(aml_land(aml_equal(has_event, one),
536                                       aml_lless(uid, aml_int(arch_ids->len))));
537                 {
538                      /*
539                       * clear loop exit condition, ins_evt/rm_evt checks will
540                       * set it to 1 while next_cpu_cmd returns a CPU with events
541                       */
542                      aml_append(while_ctx, aml_store(zero, has_event));
543 
544                      aml_append(while_ctx, aml_store(uid, cpu_selector));
545                      aml_append(while_ctx, aml_store(next_cpu_cmd, cpu_cmd));
546 
547                      /*
548                       * wrap around case, scan is complete, exit loop.
549                       * It happens since events are not cleared in scan loop,
550                       * so next_cpu_cmd continues to find already processed CPUs
551                       */
552                      ifctx = aml_if(aml_lless(cpu_data, uid));
553                      {
554                          aml_append(ifctx, aml_break());
555                      }
556                      aml_append(while_ctx, ifctx);
557 
558                      /*
559                       * if CPU_ADDED_LIST is full, exit inner loop and process
560                       * collected CPUs
561                       */
562                      ifctx = aml_if(
563                          aml_equal(num_added_cpus, aml_int(max_cpus_per_pass)));
564                      {
565                          aml_append(ifctx, aml_store(one, has_job));
566                          aml_append(ifctx, aml_break());
567                      }
568                      aml_append(while_ctx, ifctx);
569 
570                      aml_append(while_ctx, aml_store(cpu_data, uid));
571                      ifctx = aml_if(aml_equal(ins_evt, one));
572                      {
573                          /* cache added CPUs to Notify/Wakeup later */
574                          aml_append(ifctx, aml_store(uid,
575                              aml_index(new_cpus, num_added_cpus)));
576                          aml_append(ifctx, aml_increment(num_added_cpus));
577                          aml_append(ifctx, aml_store(one, has_event));
578                      }
579                      aml_append(while_ctx, ifctx);
580                      else_ctx = aml_else();
581                      ifctx = aml_if(aml_equal(rm_evt, one));
582                      {
583                          aml_append(ifctx,
584                              aml_call2(CPU_NOTIFY_METHOD, uid, eject_req));
585                          aml_append(ifctx, aml_store(one, rm_evt));
586                          aml_append(ifctx, aml_store(one, has_event));
587                      }
588                      aml_append(else_ctx, ifctx);
589                      aml_append(while_ctx, else_ctx);
590                      aml_append(while_ctx, aml_increment(uid));
591                 }
592                 aml_append(while_ctx2, while_ctx);
593 
594                 /*
595                  * in case FW negotiated ICH9_LPC_SMI_F_CPU_HOTPLUG_BIT,
596                  * make upcall to FW, so it can pull in new CPUs before
597                  * OS is notified and wakes them up
598                  */
599                 if (opts.smi_path) {
600                     ifctx = aml_if(aml_lgreater(num_added_cpus, zero));
601                     {
602                         aml_append(ifctx, aml_store(aml_int(OVMF_CPUHP_SMI_CMD),
603                             aml_name("%s", opts.smi_path)));
604                     }
605                     aml_append(while_ctx2, ifctx);
606                 }
607 
608                 /* Notify OSPM about new CPUs and clear insert events */
609                 aml_append(while_ctx2, aml_store(zero, cpu_idx));
610                 while_ctx = aml_while(aml_lless(cpu_idx, num_added_cpus));
611                 {
612                     aml_append(while_ctx,
613                         aml_store(aml_derefof(aml_index(new_cpus, cpu_idx)),
614                                   uid));
615                     aml_append(while_ctx,
616                         aml_call2(CPU_NOTIFY_METHOD, uid, dev_chk));
617                     aml_append(while_ctx, aml_store(uid, aml_debug()));
618                     aml_append(while_ctx, aml_store(uid, cpu_selector));
619                     aml_append(while_ctx, aml_store(one, ins_evt));
620                     aml_append(while_ctx, aml_increment(cpu_idx));
621                 }
622                 aml_append(while_ctx2, while_ctx);
623                 /*
624                  * If another batch is needed, then it will resume scanning
625                  * exactly at -- and not after -- the last CPU that's currently
626                  * in CPU_ADDED_LIST. In other words, the last CPU in
627                  * CPU_ADDED_LIST is going to be re-checked. That's OK: we've
628                  * just cleared the insert event for *all* CPUs in
629                  * CPU_ADDED_LIST, including the last one. So the scan will
630                  * simply seek past it.
631                  */
632             }
633             aml_append(method, while_ctx2);
634             aml_append(method, aml_release(ctrl_lock));
635         }
636         aml_append(cpus_dev, method);
637 
638         method = aml_method(CPU_OST_METHOD, 4, AML_SERIALIZED);
639         {
640             Aml *uid = aml_arg(0);
641             Aml *ev_cmd = aml_int(CPHP_OST_EVENT_CMD);
642             Aml *st_cmd = aml_int(CPHP_OST_STATUS_CMD);
643 
644             aml_append(method, aml_acquire(ctrl_lock, 0xFFFF));
645             aml_append(method, aml_store(uid, cpu_selector));
646             aml_append(method, aml_store(ev_cmd, cpu_cmd));
647             aml_append(method, aml_store(aml_arg(1), cpu_data));
648             aml_append(method, aml_store(st_cmd, cpu_cmd));
649             aml_append(method, aml_store(aml_arg(2), cpu_data));
650             aml_append(method, aml_release(ctrl_lock));
651         }
652         aml_append(cpus_dev, method);
653 
654         /* build Processor object for each processor */
655         for (i = 0; i < arch_ids->len; i++) {
656             Aml *dev;
657             Aml *uid = aml_int(i);
658             GArray *madt_buf = g_array_new(0, 1, 1);
659             int arch_id = arch_ids->cpus[i].arch_id;
660 
661             if (opts.acpi_1_compatible && arch_id < 255) {
662                 dev = aml_processor(i, 0, 0, CPU_NAME_FMT, i);
663             } else {
664                 dev = aml_device(CPU_NAME_FMT, i);
665                 aml_append(dev, aml_name_decl("_HID", aml_string("ACPI0007")));
666                 aml_append(dev, aml_name_decl("_UID", uid));
667             }
668 
669             method = aml_method("_STA", 0, AML_SERIALIZED);
670             aml_append(method, aml_return(aml_call1(CPU_STS_METHOD, uid)));
671             aml_append(dev, method);
672 
673             /* build _MAT object */
674             build_madt_cpu(i, arch_ids, madt_buf, true); /* set enabled flag */
675             aml_append(dev, aml_name_decl("_MAT",
676                 aml_buffer(madt_buf->len, (uint8_t *)madt_buf->data)));
677             g_array_free(madt_buf, true);
678 
679             if (CPU(arch_ids->cpus[i].cpu) != first_cpu) {
680                 method = aml_method("_EJ0", 1, AML_NOTSERIALIZED);
681                 aml_append(method, aml_call1(CPU_EJECT_METHOD, uid));
682                 aml_append(dev, method);
683             }
684 
685             method = aml_method("_OST", 3, AML_SERIALIZED);
686             aml_append(method,
687                 aml_call4(CPU_OST_METHOD, uid, aml_arg(0),
688                           aml_arg(1), aml_arg(2))
689             );
690             aml_append(dev, method);
691 
692             /* Linux guests discard SRAT info for non-present CPUs
693              * as a result _PXM is required for all CPUs which might
694              * be hot-plugged. For simplicity, add it for all CPUs.
695              */
696             if (arch_ids->cpus[i].props.has_node_id) {
697                 aml_append(dev, aml_name_decl("_PXM",
698                            aml_int(arch_ids->cpus[i].props.node_id)));
699             }
700 
701             aml_append(cpus_dev, dev);
702         }
703     }
704     aml_append(sb_scope, cpus_dev);
705     aml_append(table, sb_scope);
706 
707     method = aml_method(event_handler_method, 0, AML_NOTSERIALIZED);
708     aml_append(method, aml_call0("\\_SB.CPUS." CPU_SCAN_METHOD));
709     aml_append(table, method);
710 
711     g_free(cphp_res_path);
712 }
713