Add S390x virtio machine bus

On S390x we don't want to go through the hassle of emulating real existing
hardware, because we don't need to for running Linux.

So let's instead implement a machine that is 100% based on VirtIO which we
fortunately implement already.

This patch implements the bus that is the groundwork for such an S390x
virtio machine.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>

3 files changed, 461 insertions, 0 deletions

diff --git a/Makefile.target b/Makefile.target
index 891ea08221..725cbebc73 100644
--- a/Makefile.target
+++ b/Makefile.target
@@ -293,6 +293,8 @@ obj-sh4-y += ide/core.o ide/mmio.o
 obj-m68k-y = an5206.o mcf5206.o mcf_uart.o mcf_intc.o mcf5208.o mcf_fec.o
 obj-m68k-y += m68k-semi.o dummy_m68k.o
 
+obj-s390x-y = s390-virtio-bus.o
+
 main.o vl.o: QEMU_CFLAGS+=$(GPROF_CFLAGS)
 
 vl.o: QEMU_CFLAGS+=$(SDL_CFLAGS)
diff --git a/hw/s390-virtio-bus.c b/hw/s390-virtio-bus.c
new file mode 100644
index 0000000000..493e4dae44
--- /dev/null
+++ b/hw/s390-virtio-bus.c
@@ -0,0 +1,395 @@
+/*
+ * QEMU S390 virtio target
+ *
+ * Copyright (c) 2009 Alexander Graf <agraf@suse.de>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "hw.h"
+#include "block.h"
+#include "sysemu.h"
+#include "net.h"
+#include "boards.h"
+#include "monitor.h"
+#include "loader.h"
+#include "elf.h"
+#include "hw/virtio.h"
+#include "hw/virtio-console.h"
+#include "hw/sysbus.h"
+#include "kvm.h"
+
+#include "hw/s390-virtio-bus.h"
+
+/* #define DEBUG_S390 */
+
+#ifdef DEBUG_S390
+#define dprintf(fmt, ...) \
+    do { fprintf(stderr, fmt, ## __VA_ARGS__); } while (0)
+#else
+#define dprintf(fmt, ...) \
+    do { } while (0)
+#endif
+
+struct BusInfo s390_virtio_bus_info = {
+    .name       = "s390-virtio",
+    .size       = sizeof(VirtIOS390Bus),
+};
+
+typedef struct {
+    DeviceInfo qdev;
+    int (*init)(VirtIOS390Device *dev);
+} VirtIOS390DeviceInfo;
+
+
+static const VirtIOBindings virtio_s390_bindings;
+
+static ram_addr_t s390_virtio_device_num_vq(VirtIOS390Device *dev);
+static void s390_virtio_device_sync(VirtIOS390Device *dev);
+
+VirtIOS390Bus *s390_virtio_bus_init(ram_addr_t *ram_size)
+{
+    VirtIOS390Bus *bus;
+    BusState *_bus;
+    DeviceState *dev;
+
+    /* Create bridge device */
+    dev = qdev_create(NULL, "s390-virtio-bridge");
+    qdev_init_nofail(dev);
+
+    /* Create bus on bridge device */
+
+    _bus = qbus_create(&s390_virtio_bus_info, dev, "s390-virtio");
+    bus = DO_UPCAST(VirtIOS390Bus, bus, _bus);
+
+    bus->dev_page = *ram_size;
+    bus->dev_offs = bus->dev_page;
+    bus->next_ring = bus->dev_page + TARGET_PAGE_SIZE;
+
+    /* Allocate RAM for VirtIO device pages (descriptors, queues, rings) */
+    *ram_size += S390_DEVICE_PAGES * TARGET_PAGE_SIZE;
+
+    return bus;
+}
+
+static int s390_virtio_device_init(VirtIOS390Device *dev, VirtIODevice *vdev)
+{
+    VirtIOS390Bus *bus;
+    int dev_len;
+
+    bus = DO_UPCAST(VirtIOS390Bus, bus, dev->qdev.parent_bus);
+    dev->vdev = vdev;
+    dev->dev_offs = bus->dev_offs;
+    dev->feat_len = sizeof(uint32_t); /* always keep 32 bits features */
+
+    dev_len = VIRTIO_DEV_OFFS_CONFIG;
+    dev_len += s390_virtio_device_num_vq(dev) * VIRTIO_VQCONFIG_LEN;
+    dev_len += dev->feat_len * 2;
+    dev_len += vdev->config_len;
+
+    bus->dev_offs += dev_len;
+
+    virtio_bind_device(vdev, &virtio_s390_bindings, dev);
+    s390_virtio_device_sync(dev);
+
+    return 0;
+}
+
+static int s390_virtio_net_init(VirtIOS390Device *dev)
+{
+    VirtIODevice *vdev;
+
+    vdev = virtio_net_init((DeviceState *)dev, &dev->nic);
+    if (!vdev) {
+        return -1;
+    }
+
+    return s390_virtio_device_init(dev, vdev);
+}
+
+static int s390_virtio_blk_init(VirtIOS390Device *dev)
+{
+    VirtIODevice *vdev;
+
+    vdev = virtio_blk_init((DeviceState *)dev, dev->dinfo);
+    if (!vdev) {
+        return -1;
+    }
+
+    return s390_virtio_device_init(dev, vdev);
+}
+
+static int s390_virtio_console_init(VirtIOS390Device *dev)
+{
+    VirtIOS390Bus *bus;
+    VirtIODevice *vdev;
+    int r;
+
+    bus = DO_UPCAST(VirtIOS390Bus, bus, dev->qdev.parent_bus);
+
+    vdev = virtio_console_init((DeviceState *)dev);
+    if (!vdev) {
+        return -1;
+    }
+
+    r = s390_virtio_device_init(dev, vdev);
+    if (!r) {
+        bus->console = dev;
+    }
+
+    return r;
+}
+
+static uint64_t s390_virtio_device_vq_token(VirtIOS390Device *dev, int vq)
+{
+    ram_addr_t token_off;
+
+    token_off = (dev->dev_offs + VIRTIO_DEV_OFFS_CONFIG) +
+                (vq * VIRTIO_VQCONFIG_LEN) +
+                VIRTIO_VQCONFIG_OFFS_TOKEN;
+
+    return ldq_phys(token_off);
+}
+
+static ram_addr_t s390_virtio_device_num_vq(VirtIOS390Device *dev)
+{
+    VirtIODevice *vdev = dev->vdev;
+    int num_vq;
+
+    for (num_vq = 0; num_vq < VIRTIO_PCI_QUEUE_MAX; num_vq++) {
+        if (!virtio_queue_get_num(vdev, num_vq)) {
+            break;
+        }
+    }
+
+    return num_vq;
+}
+
+static ram_addr_t s390_virtio_next_ring(VirtIOS390Bus *bus)
+{
+    ram_addr_t r = bus->next_ring;
+
+    bus->next_ring += VIRTIO_RING_LEN;
+    return r;
+}
+
+static void s390_virtio_device_sync(VirtIOS390Device *dev)
+{
+    VirtIOS390Bus *bus = DO_UPCAST(VirtIOS390Bus, bus, dev->qdev.parent_bus);
+    ram_addr_t cur_offs;
+    uint8_t num_vq;
+    int i;
+
+    virtio_reset(dev->vdev);
+
+    /* Sync dev space */
+    stb_phys(dev->dev_offs + VIRTIO_DEV_OFFS_TYPE, dev->vdev->device_id);
+
+    stb_phys(dev->dev_offs + VIRTIO_DEV_OFFS_NUM_VQ, s390_virtio_device_num_vq(dev));
+    stb_phys(dev->dev_offs + VIRTIO_DEV_OFFS_FEATURE_LEN, dev->feat_len);
+
+    stb_phys(dev->dev_offs + VIRTIO_DEV_OFFS_CONFIG_LEN, dev->vdev->config_len);
+
+    num_vq = s390_virtio_device_num_vq(dev);
+    stb_phys(dev->dev_offs + VIRTIO_DEV_OFFS_NUM_VQ, num_vq);
+
+    /* Sync virtqueues */
+    for (i = 0; i < num_vq; i++) {
+        ram_addr_t vq = (dev->dev_offs + VIRTIO_DEV_OFFS_CONFIG) +
+                        (i * VIRTIO_VQCONFIG_LEN);
+        ram_addr_t vring;
+
+        vring = s390_virtio_next_ring(bus);
+        virtio_queue_set_addr(dev->vdev, i, vring);
+        virtio_queue_set_vector(dev->vdev, i, i);
+        stq_phys(vq + VIRTIO_VQCONFIG_OFFS_ADDRESS, vring);
+        stw_phys(vq + VIRTIO_VQCONFIG_OFFS_NUM, virtio_queue_get_num(dev->vdev, i));
+    }
+
+    cur_offs = dev->dev_offs;
+    cur_offs += VIRTIO_DEV_OFFS_CONFIG;
+    cur_offs += num_vq * VIRTIO_VQCONFIG_LEN;
+
+    /* Sync feature bitmap */
+    if (dev->vdev->get_features) {
+        stl_phys(cur_offs, dev->vdev->get_features(dev->vdev));
+    }
+
+    dev->feat_offs = cur_offs + dev->feat_len;
+    cur_offs += dev->feat_len * 2;
+
+    /* Sync config space */
+    if (dev->vdev->get_config) {
+        dev->vdev->get_config(dev->vdev, dev->vdev->config);
+    }
+
+    cpu_physical_memory_rw(cur_offs, dev->vdev->config, dev->vdev->config_len, 1);
+    cur_offs += dev->vdev->config_len;
+}
+
+void s390_virtio_device_update_status(VirtIOS390Device *dev)
+{
+    VirtIODevice *vdev = dev->vdev;
+    uint32_t features;
+
+    vdev->status = ldub_phys(dev->dev_offs + VIRTIO_DEV_OFFS_STATUS);
+
+    /* Update guest supported feature bitmap */
+
+    features = ldl_phys(dev->feat_offs);
+    if (vdev->set_features) {
+        vdev->set_features(vdev, features);
+    }
+    vdev->features = features;
+}
+
+VirtIOS390Device *s390_virtio_bus_console(VirtIOS390Bus *bus)
+{
+    return bus->console;
+}
+
+/* Find a device by vring address */
+VirtIOS390Device *s390_virtio_bus_find_vring(VirtIOS390Bus *bus,
+                                             ram_addr_t mem,
+                                             int *vq_num)
+{
+    VirtIOS390Device *_dev;
+    DeviceState *dev;
+    int i;
+
+    QLIST_FOREACH(dev, &bus->bus.children, sibling) {
+        _dev = (VirtIOS390Device *)dev;
+        for(i = 0; i < VIRTIO_PCI_QUEUE_MAX; i++) {
+            if (!virtio_queue_get_addr(_dev->vdev, i))
+                break;
+            if (virtio_queue_get_addr(_dev->vdev, i) == mem) {
+                if (vq_num) {
+                    *vq_num = i;
+                }
+                return _dev;
+            }
+        }
+    }
+
+    return NULL;
+}
+
+/* Find a device by device descriptor location */
+VirtIOS390Device *s390_virtio_bus_find_mem(VirtIOS390Bus *bus, ram_addr_t mem)
+{
+    VirtIOS390Device *_dev;
+    DeviceState *dev;
+
+    QLIST_FOREACH(dev, &bus->bus.children, sibling) {
+        _dev = (VirtIOS390Device *)dev;
+        if (_dev->dev_offs == mem) {
+            return _dev;
+        }
+    }
+
+    return NULL;
+}
+
+static void virtio_s390_notify(void *opaque, uint16_t vector)
+{
+    VirtIOS390Device *dev = (VirtIOS390Device*)opaque;
+    uint64_t token = s390_virtio_device_vq_token(dev, vector);
+
+    /* XXX kvm dependency! */
+    kvm_s390_virtio_irq(s390_cpu_addr2state(0), 1, token);
+}
+
+/**************** S390 Virtio Bus Device Descriptions *******************/
+
+static const VirtIOBindings virtio_s390_bindings = {
+    .notify = virtio_s390_notify,
+};
+
+static VirtIOS390DeviceInfo s390_virtio_net = {
+    .init = s390_virtio_net_init,
+    .qdev.name = "virtio-net-s390",
+    .qdev.size = sizeof(VirtIOS390Device),
+    .qdev.props = (Property[]) {
+        DEFINE_NIC_PROPERTIES(VirtIOS390Device, nic),
+        DEFINE_PROP_END_OF_LIST(),
+    },
+};
+
+static VirtIOS390DeviceInfo s390_virtio_blk = {
+    .init = s390_virtio_blk_init,
+    .qdev.name = "virtio-blk-s390",
+    .qdev.size = sizeof(VirtIOS390Device),
+    .qdev.props = (Property[]) {
+        DEFINE_PROP_DRIVE("drive", VirtIOS390Device, dinfo),
+        DEFINE_PROP_END_OF_LIST(),
+    },
+};
+
+static VirtIOS390DeviceInfo s390_virtio_console = {
+    .init = s390_virtio_console_init,
+    .qdev.name = "virtio-console-s390",
+    .qdev.size = sizeof(VirtIOS390Device),
+    .qdev.props = (Property[]) {
+        DEFINE_PROP_END_OF_LIST(),
+    },
+};
+
+static int s390_virtio_busdev_init(DeviceState *dev, DeviceInfo *info)
+{
+    VirtIOS390DeviceInfo *_info = (VirtIOS390DeviceInfo *)info;
+    VirtIOS390Device *_dev = (VirtIOS390Device *)dev;
+
+    return _info->init(_dev);
+}
+
+static void s390_virtio_bus_register_withprop(VirtIOS390DeviceInfo *info)
+{
+    info->qdev.init = s390_virtio_busdev_init;
+    info->qdev.bus_info = &s390_virtio_bus_info;
+
+    assert(info->qdev.size >= sizeof(VirtIOS390Device));
+    qdev_register(&info->qdev);
+}
+
+static void s390_virtio_register(void)
+{
+    s390_virtio_bus_register_withprop(&s390_virtio_console);
+    s390_virtio_bus_register_withprop(&s390_virtio_blk);
+    s390_virtio_bus_register_withprop(&s390_virtio_net);
+}
+device_init(s390_virtio_register);
+
+
+/***************** S390 Virtio Bus Bridge Device *******************/
+/* Only required to have the virtio bus as child in the system bus */
+
+static int s390_virtio_bridge_init(SysBusDevice *dev)
+{
+    /* nothing */
+    return 0;
+}
+
+static SysBusDeviceInfo s390_virtio_bridge_info = {
+    .init = s390_virtio_bridge_init,
+    .qdev.name  = "s390-virtio-bridge",
+    .qdev.size  = sizeof(SysBusDevice),
+    .qdev.no_user = 1,
+};
+
+static void s390_virtio_register_devices(void)
+{
+    sysbus_register_withprop(&s390_virtio_bridge_info);
+}
+
+device_init(s390_virtio_register_devices)
diff --git a/hw/s390-virtio-bus.h b/hw/s390-virtio-bus.h
new file mode 100644
index 0000000000..ef3671421a
--- /dev/null
+++ b/hw/s390-virtio-bus.h
@@ -0,0 +1,64 @@
+/*
+ * QEMU S390x VirtIO BUS definitions
+ *
+ * Copyright (c) 2009 Alexander Graf <agraf@suse.de>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#define VIRTIO_DEV_OFFS_TYPE		0	/* 8 bits */
+#define VIRTIO_DEV_OFFS_NUM_VQ		1	/* 8 bits */
+#define VIRTIO_DEV_OFFS_FEATURE_LEN	2	/* 8 bits */
+#define VIRTIO_DEV_OFFS_CONFIG_LEN	3	/* 8 bits */
+#define VIRTIO_DEV_OFFS_STATUS		4	/* 8 bits */
+#define VIRTIO_DEV_OFFS_CONFIG		5	/* dynamic */
+
+#define VIRTIO_VQCONFIG_OFFS_TOKEN	0	/* 64 bits */
+#define VIRTIO_VQCONFIG_OFFS_ADDRESS	8	/* 64 bits */
+#define VIRTIO_VQCONFIG_OFFS_NUM	16	/* 16 bits */
+#define VIRTIO_VQCONFIG_LEN		24
+
+#define VIRTIO_RING_LEN			(TARGET_PAGE_SIZE * 3)
+#define S390_DEVICE_PAGES		256
+
+typedef struct VirtIOS390Device {
+    DeviceState qdev;
+    ram_addr_t dev_offs;
+    ram_addr_t feat_offs;
+    uint8_t feat_len;
+    VirtIODevice *vdev;
+    DriveInfo *dinfo;
+    NICConf nic;
+} VirtIOS390Device;
+
+typedef struct VirtIOS390Bus {
+    BusState bus;
+
+    VirtIOS390Device *console;
+    ram_addr_t dev_page;
+    ram_addr_t dev_offs;
+    ram_addr_t next_ring;
+} VirtIOS390Bus;
+
+
+extern void s390_virtio_device_update_status(VirtIOS390Device *dev);
+
+extern VirtIOS390Device *s390_virtio_bus_console(VirtIOS390Bus *bus);
+extern VirtIOS390Bus *s390_virtio_bus_init(ram_addr_t *ram_size);
+
+extern VirtIOS390Device *s390_virtio_bus_find_vring(VirtIOS390Bus *bus,
+                                                    ram_addr_t mem,
+                                                    int *vq_num);
+extern VirtIOS390Device *s390_virtio_bus_find_mem(VirtIOS390Bus *bus,
+                                                  ram_addr_t mem);