xref: /openbmc/qemu/hw/acpi/generic_event_device.c (revision 86044b24)
1 /*
2  *
3  * Copyright (c) 2018 Intel Corporation
4  * Copyright (c) 2019 Huawei Technologies R & D (UK) Ltd
5  * Written by Samuel Ortiz, Shameer Kolothum
6  *
7  * This program is free software; you can redistribute it and/or modify it
8  * under the terms and conditions of the GNU General Public License,
9  * version 2 or later, as published by the Free Software Foundation.
10  */
11 
12 #include "qemu/osdep.h"
13 #include "qapi/error.h"
14 #include "exec/address-spaces.h"
15 #include "hw/acpi/acpi.h"
16 #include "hw/acpi/generic_event_device.h"
17 #include "hw/irq.h"
18 #include "hw/mem/pc-dimm.h"
19 #include "hw/qdev-properties.h"
20 #include "migration/vmstate.h"
21 #include "qemu/error-report.h"
22 
23 static const uint32_t ged_supported_events[] = {
24     ACPI_GED_MEM_HOTPLUG_EVT,
25     ACPI_GED_PWR_DOWN_EVT,
26 };
27 
28 /*
29  * The ACPI Generic Event Device (GED) is a hardware-reduced specific
30  * device[ACPI v6.1 Section 5.6.9] that handles all platform events,
31  * including the hotplug ones. Platforms need to specify their own
32  * GED Event bitmap to describe what kind of events they want to support
33  * through GED. This routine uses a single interrupt for the GED device,
34  * relying on IO memory region to communicate the type of device
35  * affected by the interrupt. This way, we can support up to 32 events
36  * with a unique interrupt.
37  */
38 void build_ged_aml(Aml *table, const char *name, HotplugHandler *hotplug_dev,
39                    uint32_t ged_irq, AmlRegionSpace rs, hwaddr ged_base)
40 {
41     AcpiGedState *s = ACPI_GED(hotplug_dev);
42     Aml *crs = aml_resource_template();
43     Aml *evt, *field;
44     Aml *dev = aml_device("%s", name);
45     Aml *evt_sel = aml_local(0);
46     Aml *esel = aml_name(AML_GED_EVT_SEL);
47 
48     /* _CRS interrupt */
49     aml_append(crs, aml_interrupt(AML_CONSUMER, AML_EDGE, AML_ACTIVE_HIGH,
50                                   AML_EXCLUSIVE, &ged_irq, 1));
51 
52     aml_append(dev, aml_name_decl("_HID", aml_string("ACPI0013")));
53     aml_append(dev, aml_name_decl("_UID", aml_string(GED_DEVICE)));
54     aml_append(dev, aml_name_decl("_CRS", crs));
55 
56     /* Append IO region */
57     aml_append(dev, aml_operation_region(AML_GED_EVT_REG, rs,
58                aml_int(ged_base + ACPI_GED_EVT_SEL_OFFSET),
59                ACPI_GED_EVT_SEL_LEN));
60     field = aml_field(AML_GED_EVT_REG, AML_DWORD_ACC, AML_NOLOCK,
61                       AML_WRITE_AS_ZEROS);
62     aml_append(field, aml_named_field(AML_GED_EVT_SEL,
63                                       ACPI_GED_EVT_SEL_LEN * BITS_PER_BYTE));
64     aml_append(dev, field);
65 
66     /*
67      * For each GED event we:
68      * - Add a conditional block for each event, inside a loop.
69      * - Call a method for each supported GED event type.
70      *
71      * The resulting ASL code looks like:
72      *
73      * Local0 = ESEL
74      * If ((Local0 & One) == One)
75      * {
76      *     MethodEvent0()
77      * }
78      *
79      * If ((Local0 & 0x2) == 0x2)
80      * {
81      *     MethodEvent1()
82      * }
83      * ...
84      */
85     evt = aml_method("_EVT", 1, AML_SERIALIZED);
86     {
87         Aml *if_ctx;
88         uint32_t i;
89         uint32_t ged_events = ctpop32(s->ged_event_bitmap);
90 
91         /* Local0 = ESEL */
92         aml_append(evt, aml_store(esel, evt_sel));
93 
94         for (i = 0; i < ARRAY_SIZE(ged_supported_events) && ged_events; i++) {
95             uint32_t event = s->ged_event_bitmap & ged_supported_events[i];
96 
97             if (!event) {
98                 continue;
99             }
100 
101             if_ctx = aml_if(aml_equal(aml_and(evt_sel, aml_int(event), NULL),
102                                       aml_int(event)));
103             switch (event) {
104             case ACPI_GED_MEM_HOTPLUG_EVT:
105                 aml_append(if_ctx, aml_call0(MEMORY_DEVICES_CONTAINER "."
106                                              MEMORY_SLOT_SCAN_METHOD));
107                 break;
108             case ACPI_GED_PWR_DOWN_EVT:
109                 aml_append(if_ctx,
110                            aml_notify(aml_name(ACPI_POWER_BUTTON_DEVICE),
111                                       aml_int(0x80)));
112                 break;
113             default:
114                 /*
115                  * Please make sure all the events in ged_supported_events[]
116                  * are handled above.
117                  */
118                 g_assert_not_reached();
119             }
120 
121             aml_append(evt, if_ctx);
122             ged_events--;
123         }
124 
125         if (ged_events) {
126             error_report("Unsupported events specified");
127             abort();
128         }
129     }
130 
131     /* Append _EVT method */
132     aml_append(dev, evt);
133 
134     aml_append(table, dev);
135 }
136 
137 /* Memory read by the GED _EVT AML dynamic method */
138 static uint64_t ged_read(void *opaque, hwaddr addr, unsigned size)
139 {
140     uint64_t val = 0;
141     GEDState *ged_st = opaque;
142 
143     switch (addr) {
144     case ACPI_GED_EVT_SEL_OFFSET:
145         /* Read the selector value and reset it */
146         val = ged_st->sel;
147         ged_st->sel = 0;
148         break;
149     default:
150         break;
151     }
152 
153     return val;
154 }
155 
156 /* Nothing is expected to be written to the GED memory region */
157 static void ged_write(void *opaque, hwaddr addr, uint64_t data,
158                       unsigned int size)
159 {
160 }
161 
162 static const MemoryRegionOps ged_ops = {
163     .read = ged_read,
164     .write = ged_write,
165     .endianness = DEVICE_LITTLE_ENDIAN,
166     .valid = {
167         .min_access_size = 4,
168         .max_access_size = 4,
169     },
170 };
171 
172 static void acpi_ged_device_plug_cb(HotplugHandler *hotplug_dev,
173                                     DeviceState *dev, Error **errp)
174 {
175     AcpiGedState *s = ACPI_GED(hotplug_dev);
176 
177     if (object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM)) {
178             acpi_memory_plug_cb(hotplug_dev, &s->memhp_state, dev, errp);
179     } else {
180         error_setg(errp, "virt: device plug request for unsupported device"
181                    " type: %s", object_get_typename(OBJECT(dev)));
182     }
183 }
184 
185 static void acpi_ged_send_event(AcpiDeviceIf *adev, AcpiEventStatusBits ev)
186 {
187     AcpiGedState *s = ACPI_GED(adev);
188     GEDState *ged_st = &s->ged_state;
189     uint32_t sel;
190 
191     if (ev & ACPI_MEMORY_HOTPLUG_STATUS) {
192         sel = ACPI_GED_MEM_HOTPLUG_EVT;
193     } else if (ev & ACPI_POWER_DOWN_STATUS) {
194         sel = ACPI_GED_PWR_DOWN_EVT;
195     } else {
196         /* Unknown event. Return without generating interrupt. */
197         warn_report("GED: Unsupported event %d. No irq injected", ev);
198         return;
199     }
200 
201     /*
202      * Set the GED selector field to communicate the event type.
203      * This will be read by GED aml code to select the appropriate
204      * event method.
205      */
206     ged_st->sel |= sel;
207 
208     /* Trigger the event by sending an interrupt to the guest. */
209     qemu_irq_pulse(s->irq);
210 }
211 
212 static Property acpi_ged_properties[] = {
213     DEFINE_PROP_UINT32("ged-event", AcpiGedState, ged_event_bitmap, 0),
214     DEFINE_PROP_END_OF_LIST(),
215 };
216 
217 static const VMStateDescription vmstate_memhp_state = {
218     .name = "acpi-ged/memhp",
219     .version_id = 1,
220     .minimum_version_id = 1,
221     .fields      = (VMStateField[]) {
222         VMSTATE_MEMORY_HOTPLUG(memhp_state, AcpiGedState),
223         VMSTATE_END_OF_LIST()
224     }
225 };
226 
227 static const VMStateDescription vmstate_ged_state = {
228     .name = "acpi-ged-state",
229     .version_id = 1,
230     .minimum_version_id = 1,
231     .fields      = (VMStateField[]) {
232         VMSTATE_UINT32(sel, GEDState),
233         VMSTATE_END_OF_LIST()
234     }
235 };
236 
237 static const VMStateDescription vmstate_acpi_ged = {
238     .name = "acpi-ged",
239     .version_id = 1,
240     .minimum_version_id = 1,
241     .fields = (VMStateField[]) {
242         VMSTATE_STRUCT(ged_state, AcpiGedState, 1, vmstate_ged_state, GEDState),
243         VMSTATE_END_OF_LIST(),
244     },
245     .subsections = (const VMStateDescription * []) {
246         &vmstate_memhp_state,
247         NULL
248     }
249 };
250 
251 static void acpi_ged_initfn(Object *obj)
252 {
253     DeviceState *dev = DEVICE(obj);
254     AcpiGedState *s = ACPI_GED(dev);
255     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
256     GEDState *ged_st = &s->ged_state;
257 
258     memory_region_init_io(&ged_st->io, obj, &ged_ops, ged_st,
259                           TYPE_ACPI_GED, ACPI_GED_EVT_SEL_LEN);
260     sysbus_init_mmio(sbd, &ged_st->io);
261 
262     sysbus_init_irq(sbd, &s->irq);
263 
264     s->memhp_state.is_enabled = true;
265     /*
266      * GED handles memory hotplug event and acpi-mem-hotplug
267      * memory region gets initialized here. Create an exclusive
268      * container for memory hotplug IO and expose it as GED sysbus
269      * MMIO so that boards can map it separately.
270      */
271      memory_region_init(&s->container_memhp, OBJECT(dev), "memhp container",
272                         MEMORY_HOTPLUG_IO_LEN);
273      sysbus_init_mmio(sbd, &s->container_memhp);
274      acpi_memory_hotplug_init(&s->container_memhp, OBJECT(dev),
275                               &s->memhp_state, 0);
276 }
277 
278 static void acpi_ged_class_init(ObjectClass *class, void *data)
279 {
280     DeviceClass *dc = DEVICE_CLASS(class);
281     HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(class);
282     AcpiDeviceIfClass *adevc = ACPI_DEVICE_IF_CLASS(class);
283 
284     dc->desc = "ACPI Generic Event Device";
285     dc->props = acpi_ged_properties;
286     dc->vmsd = &vmstate_acpi_ged;
287 
288     hc->plug = acpi_ged_device_plug_cb;
289 
290     adevc->send_event = acpi_ged_send_event;
291 }
292 
293 static const TypeInfo acpi_ged_info = {
294     .name          = TYPE_ACPI_GED,
295     .parent        = TYPE_SYS_BUS_DEVICE,
296     .instance_size = sizeof(AcpiGedState),
297     .instance_init  = acpi_ged_initfn,
298     .class_init    = acpi_ged_class_init,
299     .interfaces = (InterfaceInfo[]) {
300         { TYPE_HOTPLUG_HANDLER },
301         { TYPE_ACPI_DEVICE_IF },
302         { }
303     }
304 };
305 
306 static void acpi_ged_register_types(void)
307 {
308     type_register_static(&acpi_ged_info);
309 }
310 
311 type_init(acpi_ged_register_types)
312