xref: /openbmc/qemu/hw/acpi/generic_event_device.c (revision 122752d2)
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/mem/nvdimm.h"
20 #include "hw/qdev-properties.h"
21 #include "migration/vmstate.h"
22 #include "qemu/error-report.h"
23 
24 static const uint32_t ged_supported_events[] = {
25     ACPI_GED_MEM_HOTPLUG_EVT,
26     ACPI_GED_PWR_DOWN_EVT,
27     ACPI_GED_NVDIMM_HOTPLUG_EVT,
28 };
29 
30 /*
31  * The ACPI Generic Event Device (GED) is a hardware-reduced specific
32  * device[ACPI v6.1 Section 5.6.9] that handles all platform events,
33  * including the hotplug ones. Platforms need to specify their own
34  * GED Event bitmap to describe what kind of events they want to support
35  * through GED. This routine uses a single interrupt for the GED device,
36  * relying on IO memory region to communicate the type of device
37  * affected by the interrupt. This way, we can support up to 32 events
38  * with a unique interrupt.
39  */
40 void build_ged_aml(Aml *table, const char *name, HotplugHandler *hotplug_dev,
41                    uint32_t ged_irq, AmlRegionSpace rs, hwaddr ged_base)
42 {
43     AcpiGedState *s = ACPI_GED(hotplug_dev);
44     Aml *crs = aml_resource_template();
45     Aml *evt, *field;
46     Aml *dev = aml_device("%s", name);
47     Aml *evt_sel = aml_local(0);
48     Aml *esel = aml_name(AML_GED_EVT_SEL);
49 
50     /* _CRS interrupt */
51     aml_append(crs, aml_interrupt(AML_CONSUMER, AML_EDGE, AML_ACTIVE_HIGH,
52                                   AML_EXCLUSIVE, &ged_irq, 1));
53 
54     aml_append(dev, aml_name_decl("_HID", aml_string("ACPI0013")));
55     aml_append(dev, aml_name_decl("_UID", aml_string(GED_DEVICE)));
56     aml_append(dev, aml_name_decl("_CRS", crs));
57 
58     /* Append IO region */
59     aml_append(dev, aml_operation_region(AML_GED_EVT_REG, rs,
60                aml_int(ged_base + ACPI_GED_EVT_SEL_OFFSET),
61                ACPI_GED_EVT_SEL_LEN));
62     field = aml_field(AML_GED_EVT_REG, AML_DWORD_ACC, AML_NOLOCK,
63                       AML_WRITE_AS_ZEROS);
64     aml_append(field, aml_named_field(AML_GED_EVT_SEL,
65                                       ACPI_GED_EVT_SEL_LEN * BITS_PER_BYTE));
66     aml_append(dev, field);
67 
68     /*
69      * For each GED event we:
70      * - Add a conditional block for each event, inside a loop.
71      * - Call a method for each supported GED event type.
72      *
73      * The resulting ASL code looks like:
74      *
75      * Local0 = ESEL
76      * If ((Local0 & One) == One)
77      * {
78      *     MethodEvent0()
79      * }
80      *
81      * If ((Local0 & 0x2) == 0x2)
82      * {
83      *     MethodEvent1()
84      * }
85      * ...
86      */
87     evt = aml_method("_EVT", 1, AML_SERIALIZED);
88     {
89         Aml *if_ctx;
90         uint32_t i;
91         uint32_t ged_events = ctpop32(s->ged_event_bitmap);
92 
93         /* Local0 = ESEL */
94         aml_append(evt, aml_store(esel, evt_sel));
95 
96         for (i = 0; i < ARRAY_SIZE(ged_supported_events) && ged_events; i++) {
97             uint32_t event = s->ged_event_bitmap & ged_supported_events[i];
98 
99             if (!event) {
100                 continue;
101             }
102 
103             if_ctx = aml_if(aml_equal(aml_and(evt_sel, aml_int(event), NULL),
104                                       aml_int(event)));
105             switch (event) {
106             case ACPI_GED_MEM_HOTPLUG_EVT:
107                 aml_append(if_ctx, aml_call0(MEMORY_DEVICES_CONTAINER "."
108                                              MEMORY_SLOT_SCAN_METHOD));
109                 break;
110             case ACPI_GED_PWR_DOWN_EVT:
111                 aml_append(if_ctx,
112                            aml_notify(aml_name(ACPI_POWER_BUTTON_DEVICE),
113                                       aml_int(0x80)));
114                 break;
115             case ACPI_GED_NVDIMM_HOTPLUG_EVT:
116                 aml_append(if_ctx,
117                            aml_notify(aml_name("\\_SB.NVDR"),
118                                       aml_int(0x80)));
119                 break;
120             default:
121                 /*
122                  * Please make sure all the events in ged_supported_events[]
123                  * are handled above.
124                  */
125                 g_assert_not_reached();
126             }
127 
128             aml_append(evt, if_ctx);
129             ged_events--;
130         }
131 
132         if (ged_events) {
133             error_report("Unsupported events specified");
134             abort();
135         }
136     }
137 
138     /* Append _EVT method */
139     aml_append(dev, evt);
140 
141     aml_append(table, dev);
142 }
143 
144 /* Memory read by the GED _EVT AML dynamic method */
145 static uint64_t ged_read(void *opaque, hwaddr addr, unsigned size)
146 {
147     uint64_t val = 0;
148     GEDState *ged_st = opaque;
149 
150     switch (addr) {
151     case ACPI_GED_EVT_SEL_OFFSET:
152         /* Read the selector value and reset it */
153         val = ged_st->sel;
154         ged_st->sel = 0;
155         break;
156     default:
157         break;
158     }
159 
160     return val;
161 }
162 
163 /* Nothing is expected to be written to the GED memory region */
164 static void ged_write(void *opaque, hwaddr addr, uint64_t data,
165                       unsigned int size)
166 {
167 }
168 
169 static const MemoryRegionOps ged_ops = {
170     .read = ged_read,
171     .write = ged_write,
172     .endianness = DEVICE_LITTLE_ENDIAN,
173     .valid = {
174         .min_access_size = 4,
175         .max_access_size = 4,
176     },
177 };
178 
179 static void acpi_ged_device_plug_cb(HotplugHandler *hotplug_dev,
180                                     DeviceState *dev, Error **errp)
181 {
182     AcpiGedState *s = ACPI_GED(hotplug_dev);
183 
184     if (object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM)) {
185         if (object_dynamic_cast(OBJECT(dev), TYPE_NVDIMM)) {
186             nvdimm_acpi_plug_cb(hotplug_dev, dev);
187         } else {
188             acpi_memory_plug_cb(hotplug_dev, &s->memhp_state, dev, errp);
189         }
190     } else {
191         error_setg(errp, "virt: device plug request for unsupported device"
192                    " type: %s", object_get_typename(OBJECT(dev)));
193     }
194 }
195 
196 static void acpi_ged_send_event(AcpiDeviceIf *adev, AcpiEventStatusBits ev)
197 {
198     AcpiGedState *s = ACPI_GED(adev);
199     GEDState *ged_st = &s->ged_state;
200     uint32_t sel;
201 
202     if (ev & ACPI_MEMORY_HOTPLUG_STATUS) {
203         sel = ACPI_GED_MEM_HOTPLUG_EVT;
204     } else if (ev & ACPI_POWER_DOWN_STATUS) {
205         sel = ACPI_GED_PWR_DOWN_EVT;
206     } else if (ev & ACPI_NVDIMM_HOTPLUG_STATUS) {
207         sel = ACPI_GED_NVDIMM_HOTPLUG_EVT;
208     } else {
209         /* Unknown event. Return without generating interrupt. */
210         warn_report("GED: Unsupported event %d. No irq injected", ev);
211         return;
212     }
213 
214     /*
215      * Set the GED selector field to communicate the event type.
216      * This will be read by GED aml code to select the appropriate
217      * event method.
218      */
219     ged_st->sel |= sel;
220 
221     /* Trigger the event by sending an interrupt to the guest. */
222     qemu_irq_pulse(s->irq);
223 }
224 
225 static Property acpi_ged_properties[] = {
226     DEFINE_PROP_UINT32("ged-event", AcpiGedState, ged_event_bitmap, 0),
227     DEFINE_PROP_END_OF_LIST(),
228 };
229 
230 static const VMStateDescription vmstate_memhp_state = {
231     .name = "acpi-ged/memhp",
232     .version_id = 1,
233     .minimum_version_id = 1,
234     .fields      = (VMStateField[]) {
235         VMSTATE_MEMORY_HOTPLUG(memhp_state, AcpiGedState),
236         VMSTATE_END_OF_LIST()
237     }
238 };
239 
240 static const VMStateDescription vmstate_ged_state = {
241     .name = "acpi-ged-state",
242     .version_id = 1,
243     .minimum_version_id = 1,
244     .fields      = (VMStateField[]) {
245         VMSTATE_UINT32(sel, GEDState),
246         VMSTATE_END_OF_LIST()
247     }
248 };
249 
250 static const VMStateDescription vmstate_acpi_ged = {
251     .name = "acpi-ged",
252     .version_id = 1,
253     .minimum_version_id = 1,
254     .fields = (VMStateField[]) {
255         VMSTATE_STRUCT(ged_state, AcpiGedState, 1, vmstate_ged_state, GEDState),
256         VMSTATE_END_OF_LIST(),
257     },
258     .subsections = (const VMStateDescription * []) {
259         &vmstate_memhp_state,
260         NULL
261     }
262 };
263 
264 static void acpi_ged_initfn(Object *obj)
265 {
266     DeviceState *dev = DEVICE(obj);
267     AcpiGedState *s = ACPI_GED(dev);
268     SysBusDevice *sbd = SYS_BUS_DEVICE(obj);
269     GEDState *ged_st = &s->ged_state;
270 
271     memory_region_init_io(&ged_st->io, obj, &ged_ops, ged_st,
272                           TYPE_ACPI_GED, ACPI_GED_EVT_SEL_LEN);
273     sysbus_init_mmio(sbd, &ged_st->io);
274 
275     sysbus_init_irq(sbd, &s->irq);
276 
277     s->memhp_state.is_enabled = true;
278     /*
279      * GED handles memory hotplug event and acpi-mem-hotplug
280      * memory region gets initialized here. Create an exclusive
281      * container for memory hotplug IO and expose it as GED sysbus
282      * MMIO so that boards can map it separately.
283      */
284      memory_region_init(&s->container_memhp, OBJECT(dev), "memhp container",
285                         MEMORY_HOTPLUG_IO_LEN);
286      sysbus_init_mmio(sbd, &s->container_memhp);
287      acpi_memory_hotplug_init(&s->container_memhp, OBJECT(dev),
288                               &s->memhp_state, 0);
289 }
290 
291 static void acpi_ged_class_init(ObjectClass *class, void *data)
292 {
293     DeviceClass *dc = DEVICE_CLASS(class);
294     HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(class);
295     AcpiDeviceIfClass *adevc = ACPI_DEVICE_IF_CLASS(class);
296 
297     dc->desc = "ACPI Generic Event Device";
298     device_class_set_props(dc, acpi_ged_properties);
299     dc->vmsd = &vmstate_acpi_ged;
300 
301     hc->plug = acpi_ged_device_plug_cb;
302 
303     adevc->send_event = acpi_ged_send_event;
304 }
305 
306 static const TypeInfo acpi_ged_info = {
307     .name          = TYPE_ACPI_GED,
308     .parent        = TYPE_SYS_BUS_DEVICE,
309     .instance_size = sizeof(AcpiGedState),
310     .instance_init  = acpi_ged_initfn,
311     .class_init    = acpi_ged_class_init,
312     .interfaces = (InterfaceInfo[]) {
313         { TYPE_HOTPLUG_HANDLER },
314         { TYPE_ACPI_DEVICE_IF },
315         { }
316     }
317 };
318 
319 static void acpi_ged_register_types(void)
320 {
321     type_register_static(&acpi_ged_info);
322 }
323 
324 type_init(acpi_ged_register_types)
325