hw/fsi: Introduce IBM's Local bus

This is a part of patchset where IBM's Flexible Service Interface is
introduced.

The LBUS is modelled to maintain mapped memory for the devices. The
memory is mapped after CFAM config, peek table and FSI slave registers.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Ninad Palsule <ninad@linux.ibm.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
[ clg: - removed lbus_add_device() bc unused
       - removed lbus_create_device() bc used only once
       - removed "address" property
       - updated meson.build to build fsi dir
       - included an empty hw/fsi/trace-events ]
Signed-off-by: Cédric Le Goater <clg@kaod.org>

9 files changed, 82 insertions, 0 deletions

diff --git a/hw/Kconfig b/hw/Kconfig
index 9ca7b38c31..2c00936c28 100644
--- a/hw/Kconfig
+++ b/hw/Kconfig
@@ -9,6 +9,7 @@ source core/Kconfig
 source cxl/Kconfig
 source display/Kconfig
 source dma/Kconfig
+source fsi/Kconfig
 source gpio/Kconfig
 source hyperv/Kconfig
 source i2c/Kconfig
diff --git a/hw/fsi/Kconfig b/hw/fsi/Kconfig
new file mode 100644
index 0000000000..9c34a418d7
--- /dev/null
+++ b/hw/fsi/Kconfig
@@ -0,0 +1,2 @@
+config FSI
+    bool
diff --git a/hw/fsi/lbus.c b/hw/fsi/lbus.c
new file mode 100644
index 0000000000..44d2319087
--- /dev/null
+++ b/hw/fsi/lbus.c
@@ -0,0 +1,43 @@
+/*
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ * Copyright (C) 2024 IBM Corp.
+ *
+ * IBM Local bus where FSI slaves are connected
+ */
+
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+#include "hw/fsi/lbus.h"
+
+#include "hw/qdev-properties.h"
+
+#include "trace.h"
+
+static void fsi_lbus_init(Object *o)
+{
+    FSILBus *lbus = FSI_LBUS(o);
+
+    memory_region_init(&lbus->mr, OBJECT(lbus), TYPE_FSI_LBUS, 1 * MiB);
+}
+
+static const TypeInfo fsi_lbus_info = {
+    .name = TYPE_FSI_LBUS,
+    .parent = TYPE_BUS,
+    .instance_init = fsi_lbus_init,
+    .instance_size = sizeof(FSILBus),
+};
+
+static const TypeInfo fsi_lbus_device_type_info = {
+    .name = TYPE_FSI_LBUS_DEVICE,
+    .parent = TYPE_DEVICE,
+    .instance_size = sizeof(FSILBusDevice),
+    .abstract = true,
+};
+
+static void fsi_lbus_register_types(void)
+{
+    type_register_static(&fsi_lbus_info);
+    type_register_static(&fsi_lbus_device_type_info);
+}
+
+type_init(fsi_lbus_register_types);
diff --git a/hw/fsi/meson.build b/hw/fsi/meson.build
new file mode 100644
index 0000000000..93ba19dd04
--- /dev/null
+++ b/hw/fsi/meson.build
@@ -0,0 +1 @@
+system_ss.add(when: 'CONFIG_FSI', if_true: files('lbus.c'))
diff --git a/hw/fsi/trace-events b/hw/fsi/trace-events
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/hw/fsi/trace-events
diff --git a/hw/fsi/trace.h b/hw/fsi/trace.h
new file mode 100644
index 0000000000..ee67c7fb04
--- /dev/null
+++ b/hw/fsi/trace.h
@@ -0,0 +1 @@
+#include "trace/trace-hw_fsi.h"
diff --git a/hw/meson.build b/hw/meson.build
index f01fac4617..463d702683 100644
--- a/hw/meson.build
+++ b/hw/meson.build
@@ -44,6 +44,7 @@ subdir('virtio')
 subdir('watchdog')
 subdir('xen')
 subdir('xenpv')
+subdir('fsi')
 
 subdir('alpha')
 subdir('arm')
diff --git a/include/hw/fsi/lbus.h b/include/hw/fsi/lbus.h
new file mode 100644
index 0000000000..e8a22e22a8
--- /dev/null
+++ b/include/hw/fsi/lbus.h
@@ -0,0 +1,32 @@
+/*
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ * Copyright (C) 2024 IBM Corp.
+ *
+ * IBM Local bus and connected device structures.
+ */
+#ifndef FSI_LBUS_H
+#define FSI_LBUS_H
+
+#include "hw/qdev-core.h"
+#include "qemu/units.h"
+#include "exec/memory.h"
+
+#define TYPE_FSI_LBUS_DEVICE "fsi.lbus.device"
+OBJECT_DECLARE_SIMPLE_TYPE(FSILBusDevice, FSI_LBUS_DEVICE)
+
+typedef struct FSILBusDevice {
+    DeviceState parent;
+
+    MemoryRegion iomem;
+} FSILBusDevice;
+
+#define TYPE_FSI_LBUS "fsi.lbus"
+OBJECT_DECLARE_SIMPLE_TYPE(FSILBus, FSI_LBUS)
+
+typedef struct FSILBus {
+    BusState bus;
+
+    MemoryRegion mr;
+} FSILBus;
+
+#endif /* FSI_LBUS_H */
diff --git a/meson.build b/meson.build
index 5ffa8c9716..b5d6dc94a8 100644
--- a/meson.build
+++ b/meson.build
@@ -3289,6 +3289,7 @@ if have_system
     'hw/char',
     'hw/display',
     'hw/dma',
+    'hw/fsi',
     'hw/hyperv',
     'hw/i2c',
     'hw/i386',