hyperv: Add mmio_size attribute to device nodes

Some devices such as graphics and PCI passthrough bridges require
MMIO space. Add this as a device node attribute if present.

Change-Id: Id374ff61c29c1ccad10e3a7f3f7053c14d02aa5e
Reviewed-on: https://review.haiku-os.org/c/haiku/+/10483
Tested-by: Commit checker robot <[email protected]>
Reviewed-by: Jérôme Duval <[email protected]>

headers/private/hyperv/hyperv.h

@@ -17,6 +17,7 @@
 #define HYPERV_CHANNEL_ID_ITEM				"hyperv/channel"
 #define HYPERV_DEVICE_TYPE_STRING_ITEM		"hyperv/type_string"
 #define HYPERV_INSTANCE_ID_ITEM				"hyperv/instance"
+#define HYPERV_MMIO_SIZE_ITEM				"hyperv/mmio_size"
 
 #define HYPERV_PRETTYNAME_VMBUS				"Hyper-V Virtual Machine Bus"
 #define HYPERV_PRETTYNAME_VMBUS_DEVICE_FMT	"Hyper-V Channel %u"

src/add-ons/kernel/bus_managers/hyperv/VMBus.cpp

@@ -697,6 +697,7 @@ VMBus::_ProcessPendingMessage(int32_t cpu)
 					channel->dedicated_int = offerMessage->dedicated_int != 0;
 					channel->connection_id = offerMessage->connection_id;
 				}
+				channel->mmio_size = static_cast<uint32>(offerMessage->mmio_size_mb) * 1024 * 1024;
 
 				// Add new channel to offer queue and signal the channel handler thread
 				MutexLocker locker(fChannelQueueLock);
@@ -1093,7 +1094,7 @@ VMBus::_RegisterChannel(VMBusChannel* channel)
 	snprintf(prettyName, sizeof(prettyName), HYPERV_PRETTYNAME_VMBUS_DEVICE_FMT,
 		channel->channel_id);
 
-	device_attr attributes[] = {
+	device_attr attributes[10] = {
 		{ B_DEVICE_BUS, B_STRING_TYPE,
 			{ .string = HYPERV_BUS_NAME }},
 		{ B_DEVICE_PRETTY_NAME, B_STRING_TYPE,
@@ -1107,6 +1108,17 @@ VMBus::_RegisterChannel(VMBusChannel* channel)
 		{ NULL }
 	};
 
+	uint32 attributeCount = 5;
+
+	// Add MMIO attribute if present (typically PCI passthrough and graphics)
+	if (channel->mmio_size > 0) {
+		attributes[attributeCount] = {
+			HYPERV_MMIO_SIZE_ITEM, B_UINT32_TYPE,
+				{ .ui32 = channel->mmio_size }
+		};
+		attributeCount++;
+	}
+
 	// Add to active channel list
 	InterruptsSpinLocker spinLocker(fChannelsSpinlock);
 	if (fHighestChannelID < channel->channel_id)

src/add-ons/kernel/bus_managers/hyperv/VMBusPrivate.h

@@ -90,11 +90,12 @@ struct VMBusChannel : DoublyLinkedListLinkImpl<VMBusChannel> {
 		mutex_destroy(&lock);
 	}
 
-	uint32_t			channel_id;
+	uint32				channel_id;
 	vmbus_guid_t		type_id;
 	vmbus_guid_t		instance_id;
 	bool				dedicated_int;
-	uint32_t			connection_id;
+	uint32				connection_id;
+	uint32				mmio_size;
 
 	mutex				lock;
 	device_node*		node;