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
26static 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
34static 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
48static 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
58static void acpi_set_cpu_present_bit(AcpiCpuHotplug *g, CPUState *cpu,
59 Error **errp)
60{
61 CPUClass *k = CPU_GET_CLASS(cpu);
62 int64_t cpu_id;
63
64 cpu_id = k->get_arch_id(cpu);
65 if ((cpu_id / 8) >= ACPI_GPE_PROC_LEN) {
66 object_property_set_bool(g->device, false, "cpu-hotplug-legacy",
67 &error_abort);
68 return;
69 }
70
71 g->sts[cpu_id / 8] |= (1 << (cpu_id % 8));
72}
73
74void legacy_acpi_cpu_plug_cb(HotplugHandler *hotplug_dev,
75 AcpiCpuHotplug *g, DeviceState *dev, Error **errp)
76{
77 acpi_set_cpu_present_bit(g, CPU(dev), errp);
78 if (*errp != NULL) {
79 return;
80 }
81 acpi_send_event(DEVICE(hotplug_dev), ACPI_CPU_HOTPLUG_STATUS);
82}
83
84void 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, &error_abort);
96 }
97}
98
99void 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
109void 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 PCMachineState *pcms = PC_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 (pcms->apic_id_limit > ACPI_CPU_HOTPLUG_ID_LIMIT) {
240 error_report("max_cpus is too large. APIC ID of last CPU is %u",
241 pcms->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 apic_id = apic_ids->cpus[i].arch_id;
269
270 assert(apic_id < ACPI_CPU_HOTPLUG_ID_LIMIT);
271
272 dev = aml_processor(i, 0, 0, "CP%.02X", apic_id);
273
274 method = aml_method("_MAT", 0, AML_NOTSERIALIZED);
275 aml_append(method,
276 aml_return(aml_call2(CPU_MAT_METHOD, aml_int(apic_id), aml_int(i))
277 ));
278 aml_append(dev, method);
279
280 method = aml_method("_STA", 0, AML_NOTSERIALIZED);
281 aml_append(method,
282 aml_return(aml_call1(CPU_STATUS_METHOD, aml_int(apic_id))));
283 aml_append(dev, method);
284
285 method = aml_method("_EJ0", 1, AML_NOTSERIALIZED);
286 aml_append(method,
287 aml_return(aml_call2(CPU_EJECT_METHOD, aml_int(apic_id),
288 aml_arg(0)))
289 );
290 aml_append(dev, method);
291
292 aml_append(sb_scope, dev);
293 }
294
295 /* build this code:
296 * Method(NTFY, 2) {If (LEqual(Arg0, 0x00)) {Notify(CP00, Arg1)} ...}
297 */
298 /* Arg0 = APIC ID */
299 method = aml_method(AML_NOTIFY_METHOD, 2, AML_NOTSERIALIZED);
300 for (i = 0; i < apic_ids->len; i++) {
301 int apic_id = apic_ids->cpus[i].arch_id;
302
303 if_ctx = aml_if(aml_equal(aml_arg(0), aml_int(apic_id)));
304 aml_append(if_ctx,
305 aml_notify(aml_name("CP%.02X", apic_id), aml_arg(1))
306 );
307 aml_append(method, if_ctx);
308 }
309 aml_append(sb_scope, method);
310
311 /* build "Name(CPON, Package() { One, One, ..., Zero, Zero, ... })"
312 *
313 * Note: The ability to create variable-sized packages was first
314 * introduced in ACPI 2.0. ACPI 1.0 only allowed fixed-size packages
315 * ith up to 255 elements. Windows guests up to win2k8 fail when
316 * VarPackageOp is used.
317 */
318 pkg = pcms->apic_id_limit <= 255 ? aml_package(pcms->apic_id_limit) :
319 aml_varpackage(pcms->apic_id_limit);
320
321 for (i = 0, apic_idx = 0; i < apic_ids->len; i++) {
322 int apic_id = apic_ids->cpus[i].arch_id;
323
324 for (; apic_idx < apic_id; apic_idx++) {
325 aml_append(pkg, aml_int(0));
326 }
327 aml_append(pkg, aml_int(apic_ids->cpus[i].cpu ? 1 : 0));
328 apic_idx = apic_id + 1;
329 }
330 aml_append(sb_scope, aml_name_decl(CPU_ON_BITMAP, pkg));
331 aml_append(ctx, sb_scope);
332
333 method = aml_method("\\_GPE._E02", 0, AML_NOTSERIALIZED);
334 aml_append(method, aml_call0("\\_SB." CPU_SCAN_METHOD));
335 aml_append(ctx, method);
336}
337