i386: Hyper-V VMBus ACPI DSDT entry

Guest OS uses ACPI to discover VMBus presence.  Add a corresponding
entry to DSDT in case VMBus has been enabled.

Experimentally Windows guests were found to require this entry to
include two IRQ resources. They seem to never be used but they still
have to be there.

Make IRQ numbers user-configurable via corresponding properties; use 7
and 13 by default.

Signed-off-by: Evgeny Yakovlev <eyakovlev@virtuozzo.com>
Signed-off-by: Roman Kagan <rkagan@virtuozzo.com>
Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Signed-off-by: Jon Doron <arilou@gmail.com>
Message-Id: <20200424123444.3481728-6-arilou@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 43 insertions, 0 deletions

diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index 2e15f6848e..dcdfbd8906 100644
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -50,6 +50,7 @@
 #include "hw/mem/nvdimm.h"
 #include "sysemu/numa.h"
 #include "sysemu/reset.h"
+#include "hw/hyperv/vmbus-bridge.h"
 
 /* Supported chipsets: */
 #include "hw/southbridge/piix.h"
@@ -1270,9 +1271,47 @@ static Aml *build_com_device_aml(uint8_t uid)
     return dev;
 }
 
+static Aml *build_vmbus_device_aml(VMBusBridge *vmbus_bridge)
+{
+    Aml *dev;
+    Aml *method;
+    Aml *crs;
+
+    dev = aml_device("VMBS");
+    aml_append(dev, aml_name_decl("STA", aml_int(0xF)));
+    aml_append(dev, aml_name_decl("_HID", aml_string("VMBus")));
+    aml_append(dev, aml_name_decl("_UID", aml_int(0x0)));
+    aml_append(dev, aml_name_decl("_DDN", aml_string("VMBUS")));
+
+    method = aml_method("_DIS", 0, AML_NOTSERIALIZED);
+    aml_append(method, aml_store(aml_and(aml_name("STA"), aml_int(0xD), NULL),
+                                     aml_name("STA")));
+    aml_append(dev, method);
+
+    method = aml_method("_PS0", 0, AML_NOTSERIALIZED);
+    aml_append(method, aml_store(aml_or(aml_name("STA"), aml_int(0xF), NULL),
+                                     aml_name("STA")));
+    aml_append(dev, method);
+
+    method = aml_method("_STA", 0, AML_NOTSERIALIZED);
+    aml_append(method, aml_return(aml_name("STA")));
+    aml_append(dev, method);
+
+    aml_append(dev, aml_name_decl("_PS3", aml_int(0x0)));
+
+    crs = aml_resource_template();
+    aml_append(crs, aml_irq_no_flags(vmbus_bridge->irq0));
+    /* FIXME: newer HyperV gets by with only one IRQ */
+    aml_append(crs, aml_irq_no_flags(vmbus_bridge->irq1));
+    aml_append(dev, aml_name_decl("_CRS", crs));
+
+    return dev;
+}
+
 static void build_isa_devices_aml(Aml *table)
 {
     ISADevice *fdc = pc_find_fdc0();
+    VMBusBridge *vmbus_bridge = vmbus_bridge_find();
     bool ambiguous;
 
     Aml *scope = aml_scope("_SB.PCI0.ISA");
@@ -1297,6 +1336,10 @@ static void build_isa_devices_aml(Aml *table)
         isa_build_aml(ISA_BUS(obj), scope);
     }
 
+    if (vmbus_bridge) {
+        aml_append(scope, build_vmbus_device_aml(vmbus_bridge));
+    }
+
     aml_append(table, scope);
 }