From 4b52530be987f33f8bffbdec9826298ad53ec180 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Tue, 16 Jul 2013 13:25:09 +0100 Subject: [PATCH] virtio: Implement MMIO based virtio transport Add support for the generic MMIO based virtio transport. This patch includes some fixes for bugs spotted by Ying-Shiuan Pan . Signed-off-by: Peter Maydell Signed-off-by: KONRAD Frederic Message-id: 1373977512-28932-6-git-send-email-peter.maydell@linaro.org [Fred changes: updated to new virtio-bus mechanisms] Signed-off-by: KONRAD Frederic [PMM changes: * fixed trivial makefile conflict * removed unused int_enable * host_features doesn't need migrating * reset guest accessible state in the reset function * minor style fixes like extra blank lines * RAZ/WI if there's no backend * made transport size 0x200, in line with kvmtool * set has_variable_vring_alignment ] --- hw/virtio/Makefile.objs | 1 + hw/virtio/virtio-mmio.c | 421 ++++++++++++++++++++++++++++++++++++++++ 2 files changed, 422 insertions(+) create mode 100644 hw/virtio/virtio-mmio.c diff --git a/hw/virtio/Makefile.objs b/hw/virtio/Makefile.objs index cbe6d51f7a..1ba53d9cc3 100644 --- a/hw/virtio/Makefile.objs +++ b/hw/virtio/Makefile.objs @@ -1,6 +1,7 @@ common-obj-y += virtio-rng.o common-obj-$(CONFIG_VIRTIO_PCI) += virtio-pci.o common-obj-y += virtio-bus.o +common-obj-y += virtio-mmio.o common-obj-$(CONFIG_VIRTIO_BLK_DATA_PLANE) += dataplane/ obj-y += virtio.o virtio-balloon.o diff --git a/hw/virtio/virtio-mmio.c b/hw/virtio/virtio-mmio.c new file mode 100644 index 0000000000..54d6679516 --- /dev/null +++ b/hw/virtio/virtio-mmio.c @@ -0,0 +1,421 @@ +/* + * Virtio MMIO bindings + * + * Copyright (c) 2011 Linaro Limited + * + * Author: + * Peter Maydell + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License; either version 2 + * of the License, or (at your option) any later version. + * + * This program 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 General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, see . + */ + +#include "hw/sysbus.h" +#include "hw/virtio/virtio.h" +#include "qemu/host-utils.h" +#include "hw/virtio/virtio-bus.h" + +/* #define DEBUG_VIRTIO_MMIO */ + +#ifdef DEBUG_VIRTIO_MMIO + +#define DPRINTF(fmt, ...) \ +do { printf("virtio_mmio: " fmt , ## __VA_ARGS__); } while (0) +#else +#define DPRINTF(fmt, ...) do {} while (0) +#endif + +/* QOM macros */ +/* virtio-mmio-bus */ +#define TYPE_VIRTIO_MMIO_BUS "virtio-mmio-bus" +#define VIRTIO_MMIO_BUS(obj) \ + OBJECT_CHECK(VirtioBusState, (obj), TYPE_VIRTIO_MMIO_BUS) +#define VIRTIO_MMIO_BUS_GET_CLASS(obj) \ + OBJECT_GET_CLASS(VirtioBusClass, (obj), TYPE_VIRTIO_MMIO_BUS) +#define VIRTIO_MMIO_BUS_CLASS(klass) \ + OBJECT_CLASS_CHECK(VirtioBusClass, (klass), TYPE_VIRTIO_MMIO_BUS) + +/* virtio-mmio */ +#define TYPE_VIRTIO_MMIO "virtio-mmio" +#define VIRTIO_MMIO(obj) \ + OBJECT_CHECK(VirtIOMMIOProxy, (obj), TYPE_VIRTIO_MMIO) + +/* Memory mapped register offsets */ +#define VIRTIO_MMIO_MAGIC 0x0 +#define VIRTIO_MMIO_VERSION 0x4 +#define VIRTIO_MMIO_DEVICEID 0x8 +#define VIRTIO_MMIO_VENDORID 0xc +#define VIRTIO_MMIO_HOSTFEATURES 0x10 +#define VIRTIO_MMIO_HOSTFEATURESSEL 0x14 +#define VIRTIO_MMIO_GUESTFEATURES 0x20 +#define VIRTIO_MMIO_GUESTFEATURESSEL 0x24 +#define VIRTIO_MMIO_GUESTPAGESIZE 0x28 +#define VIRTIO_MMIO_QUEUESEL 0x30 +#define VIRTIO_MMIO_QUEUENUMMAX 0x34 +#define VIRTIO_MMIO_QUEUENUM 0x38 +#define VIRTIO_MMIO_QUEUEALIGN 0x3c +#define VIRTIO_MMIO_QUEUEPFN 0x40 +#define VIRTIO_MMIO_QUEUENOTIFY 0x50 +#define VIRTIO_MMIO_INTERRUPTSTATUS 0x60 +#define VIRTIO_MMIO_INTERRUPTACK 0x64 +#define VIRTIO_MMIO_STATUS 0x70 +/* Device specific config space starts here */ +#define VIRTIO_MMIO_CONFIG 0x100 + +#define VIRT_MAGIC 0x74726976 /* 'virt' */ +#define VIRT_VERSION 1 +#define VIRT_VENDOR 0x554D4551 /* 'QEMU' */ + +typedef struct { + /* Generic */ + SysBusDevice parent_obj; + MemoryRegion iomem; + qemu_irq irq; + uint32_t host_features; + /* Guest accessible state needing migration and reset */ + uint32_t host_features_sel; + uint32_t guest_features_sel; + uint32_t guest_page_shift; + /* virtio-bus */ + VirtioBusState bus; +} VirtIOMMIOProxy; + +static void virtio_mmio_bus_new(VirtioBusState *bus, VirtIOMMIOProxy *dev); + +static uint64_t virtio_mmio_read(void *opaque, hwaddr offset, unsigned size) +{ + VirtIOMMIOProxy *proxy = (VirtIOMMIOProxy *)opaque; + VirtIODevice *vdev = proxy->bus.vdev; + + DPRINTF("virtio_mmio_read offset 0x%x\n", (int)offset); + + if (!vdev) { + /* If no backend is present, we treat most registers as + * read-as-zero, except for the magic number, version and + * vendor ID. This is not strictly sanctioned by the virtio + * spec, but it allows us to provide transports with no backend + * plugged in which don't confuse Linux's virtio code: the + * probe won't complain about the bad magic number, but the + * device ID of zero means no backend will claim it. + */ + switch (offset) { + case VIRTIO_MMIO_MAGIC: + return VIRT_MAGIC; + case VIRTIO_MMIO_VERSION: + return VIRT_VERSION; + case VIRTIO_MMIO_VENDORID: + return VIRT_VENDOR; + default: + return 0; + } + } + + if (offset >= VIRTIO_MMIO_CONFIG) { + offset -= VIRTIO_MMIO_CONFIG; + switch (size) { + case 1: + return virtio_config_readb(vdev, offset); + case 2: + return virtio_config_readw(vdev, offset); + case 4: + return virtio_config_readl(vdev, offset); + default: + abort(); + } + } + if (size != 4) { + DPRINTF("wrong size access to register!\n"); + return 0; + } + switch (offset) { + case VIRTIO_MMIO_MAGIC: + return VIRT_MAGIC; + case VIRTIO_MMIO_VERSION: + return VIRT_VERSION; + case VIRTIO_MMIO_DEVICEID: + return vdev->device_id; + case VIRTIO_MMIO_VENDORID: + return VIRT_VENDOR; + case VIRTIO_MMIO_HOSTFEATURES: + if (proxy->host_features_sel) { + return 0; + } + return proxy->host_features; + case VIRTIO_MMIO_QUEUENUMMAX: + return VIRTQUEUE_MAX_SIZE; + case VIRTIO_MMIO_QUEUEPFN: + return virtio_queue_get_addr(vdev, vdev->queue_sel) + >> proxy->guest_page_shift; + case VIRTIO_MMIO_INTERRUPTSTATUS: + return vdev->isr; + case VIRTIO_MMIO_STATUS: + return vdev->status; + case VIRTIO_MMIO_HOSTFEATURESSEL: + case VIRTIO_MMIO_GUESTFEATURES: + case VIRTIO_MMIO_GUESTFEATURESSEL: + case VIRTIO_MMIO_GUESTPAGESIZE: + case VIRTIO_MMIO_QUEUESEL: + case VIRTIO_MMIO_QUEUENUM: + case VIRTIO_MMIO_QUEUEALIGN: + case VIRTIO_MMIO_QUEUENOTIFY: + case VIRTIO_MMIO_INTERRUPTACK: + DPRINTF("read of write-only register\n"); + return 0; + default: + DPRINTF("bad register offset\n"); + return 0; + } + return 0; +} + +static void virtio_mmio_write(void *opaque, hwaddr offset, uint64_t value, + unsigned size) +{ + VirtIOMMIOProxy *proxy = (VirtIOMMIOProxy *)opaque; + VirtIODevice *vdev = proxy->bus.vdev; + + DPRINTF("virtio_mmio_write offset 0x%x value 0x%" PRIx64 "\n", + (int)offset, value); + + if (!vdev) { + /* If no backend is present, we just make all registers + * write-ignored. This allows us to provide transports with + * no backend plugged in. + */ + return; + } + + if (offset >= VIRTIO_MMIO_CONFIG) { + offset -= VIRTIO_MMIO_CONFIG; + switch (size) { + case 1: + virtio_config_writeb(vdev, offset, value); + break; + case 2: + virtio_config_writew(vdev, offset, value); + break; + case 4: + virtio_config_writel(vdev, offset, value); + break; + default: + abort(); + } + return; + } + if (size != 4) { + DPRINTF("wrong size access to register!\n"); + return; + } + switch (offset) { + case VIRTIO_MMIO_HOSTFEATURESSEL: + proxy->host_features_sel = value; + break; + case VIRTIO_MMIO_GUESTFEATURES: + if (!proxy->guest_features_sel) { + virtio_set_features(vdev, value); + } + break; + case VIRTIO_MMIO_GUESTFEATURESSEL: + proxy->guest_features_sel = value; + break; + case VIRTIO_MMIO_GUESTPAGESIZE: + proxy->guest_page_shift = ctz32(value); + if (proxy->guest_page_shift > 31) { + proxy->guest_page_shift = 0; + } + DPRINTF("guest page size %" PRIx64 " shift %d\n", value, + proxy->guest_page_shift); + break; + case VIRTIO_MMIO_QUEUESEL: + if (value < VIRTIO_PCI_QUEUE_MAX) { + vdev->queue_sel = value; + } + break; + case VIRTIO_MMIO_QUEUENUM: + DPRINTF("mmio_queue write %d max %d\n", (int)value, VIRTQUEUE_MAX_SIZE); + virtio_queue_set_num(vdev, vdev->queue_sel, value); + break; + case VIRTIO_MMIO_QUEUEALIGN: + virtio_queue_set_align(vdev, vdev->queue_sel, value); + break; + case VIRTIO_MMIO_QUEUEPFN: + if (value == 0) { + virtio_reset(vdev); + } else { + virtio_queue_set_addr(vdev, vdev->queue_sel, + value << proxy->guest_page_shift); + } + break; + case VIRTIO_MMIO_QUEUENOTIFY: + if (value < VIRTIO_PCI_QUEUE_MAX) { + virtio_queue_notify(vdev, value); + } + break; + case VIRTIO_MMIO_INTERRUPTACK: + vdev->isr &= ~value; + virtio_update_irq(vdev); + break; + case VIRTIO_MMIO_STATUS: + virtio_set_status(vdev, value & 0xff); + if (vdev->status == 0) { + virtio_reset(vdev); + } + break; + case VIRTIO_MMIO_MAGIC: + case VIRTIO_MMIO_VERSION: + case VIRTIO_MMIO_DEVICEID: + case VIRTIO_MMIO_VENDORID: + case VIRTIO_MMIO_HOSTFEATURES: + case VIRTIO_MMIO_QUEUENUMMAX: + case VIRTIO_MMIO_INTERRUPTSTATUS: + DPRINTF("write to readonly register\n"); + break; + + default: + DPRINTF("bad register offset\n"); + } +} + +static const MemoryRegionOps virtio_mem_ops = { + .read = virtio_mmio_read, + .write = virtio_mmio_write, + .endianness = DEVICE_NATIVE_ENDIAN, +}; + +static void virtio_mmio_update_irq(DeviceState *opaque, uint16_t vector) +{ + VirtIOMMIOProxy *proxy = VIRTIO_MMIO(opaque); + int level; + + if (!proxy->bus.vdev) { + return; + } + level = (proxy->bus.vdev->isr != 0); + DPRINTF("virtio_mmio setting IRQ %d\n", level); + qemu_set_irq(proxy->irq, level); +} + +static unsigned int virtio_mmio_get_features(DeviceState *opaque) +{ + VirtIOMMIOProxy *proxy = VIRTIO_MMIO(opaque); + + return proxy->host_features; +} + +static int virtio_mmio_load_config(DeviceState *opaque, QEMUFile *f) +{ + VirtIOMMIOProxy *proxy = VIRTIO_MMIO(opaque); + + proxy->host_features_sel = qemu_get_be32(f); + proxy->guest_features_sel = qemu_get_be32(f); + proxy->guest_page_shift = qemu_get_be32(f); + return 0; +} + +static void virtio_mmio_save_config(DeviceState *opaque, QEMUFile *f) +{ + VirtIOMMIOProxy *proxy = VIRTIO_MMIO(opaque); + + qemu_put_be32(f, proxy->host_features_sel); + qemu_put_be32(f, proxy->guest_features_sel); + qemu_put_be32(f, proxy->guest_page_shift); +} + +static void virtio_mmio_reset(DeviceState *d) +{ + VirtIOMMIOProxy *proxy = VIRTIO_MMIO(d); + + virtio_bus_reset(&proxy->bus); + proxy->host_features_sel = 0; + proxy->guest_features_sel = 0; + proxy->guest_page_shift = 0; +} + +/* virtio-mmio device */ + +/* This is called by virtio-bus just after the device is plugged. */ +static void virtio_mmio_device_plugged(DeviceState *opaque) +{ + VirtIOMMIOProxy *proxy = VIRTIO_MMIO(opaque); + + proxy->host_features |= (0x1 << VIRTIO_F_NOTIFY_ON_EMPTY); + proxy->host_features = virtio_bus_get_vdev_features(&proxy->bus, + proxy->host_features); +} + +static void virtio_mmio_realizefn(DeviceState *d, Error **errp) +{ + VirtIOMMIOProxy *proxy = VIRTIO_MMIO(d); + SysBusDevice *sbd = SYS_BUS_DEVICE(d); + + virtio_mmio_bus_new(&proxy->bus, proxy); + sysbus_init_irq(sbd, &proxy->irq); + memory_region_init_io(&proxy->iomem, OBJECT(d), &virtio_mem_ops, proxy, + TYPE_VIRTIO_MMIO, 0x200); + sysbus_init_mmio(sbd, &proxy->iomem); +} + +static void virtio_mmio_class_init(ObjectClass *klass, void *data) +{ + DeviceClass *dc = DEVICE_CLASS(klass); + + dc->realize = virtio_mmio_realizefn; + dc->reset = virtio_mmio_reset; +} + +static const TypeInfo virtio_mmio_info = { + .name = TYPE_VIRTIO_MMIO, + .parent = TYPE_SYS_BUS_DEVICE, + .instance_size = sizeof(VirtIOMMIOProxy), + .class_init = virtio_mmio_class_init, +}; + +/* virtio-mmio-bus. */ + +static void virtio_mmio_bus_new(VirtioBusState *bus, VirtIOMMIOProxy *dev) +{ + DeviceState *qdev = DEVICE(dev); + BusState *qbus; + + qbus_create_inplace((BusState *)bus, TYPE_VIRTIO_MMIO_BUS, qdev, NULL); + qbus = BUS(bus); + qbus->allow_hotplug = 0; +} + +static void virtio_mmio_bus_class_init(ObjectClass *klass, void *data) +{ + BusClass *bus_class = BUS_CLASS(klass); + VirtioBusClass *k = VIRTIO_BUS_CLASS(klass); + + k->notify = virtio_mmio_update_irq; + k->save_config = virtio_mmio_save_config; + k->load_config = virtio_mmio_load_config; + k->get_features = virtio_mmio_get_features; + k->device_plugged = virtio_mmio_device_plugged; + k->has_variable_vring_alignment = true; + bus_class->max_dev = 1; +} + +static const TypeInfo virtio_mmio_bus_info = { + .name = TYPE_VIRTIO_MMIO_BUS, + .parent = TYPE_VIRTIO_BUS, + .instance_size = sizeof(VirtioBusState), + .class_init = virtio_mmio_bus_class_init, +}; + +static void virtio_mmio_register_types(void) +{ + type_register_static(&virtio_mmio_bus_info); + type_register_static(&virtio_mmio_info); +} + +type_init(virtio_mmio_register_types) -- 2.34.1