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
cpu_status_read(void * opaque,hwaddr addr,unsigned int size)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
cpu_status_write(void * opaque,hwaddr addr,uint64_t data,unsigned int size)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
acpi_set_cpu_present_bit(AcpiCpuHotplug * g,CPUState * cpu,bool * swtchd_to_modern)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
legacy_acpi_cpu_plug_cb(HotplugHandler * hotplug_dev,AcpiCpuHotplug * g,DeviceState * dev,Error ** errp)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
legacy_acpi_cpu_hotplug_init(MemoryRegion * parent,Object * owner,AcpiCpuHotplug * gpe_cpu,uint16_t base)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
acpi_switch_to_modern_cphp(AcpiCpuHotplug * gpe_cpu,CPUHotplugState * cpuhp_state,uint16_t io_port)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
build_legacy_cpu_hotplug_aml(Aml * ctx,MachineState * machine,uint16_t io_base)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