Pawel Moll
2011-Oct-27 02:26 UTC
[PATCH v3] virtio: Add platform bus driver for memory mapped virtio device
On Mon, 2011-10-24 at 03:33 +0100, Rusty Russell wrote:> No, that's it I think. Please send a diff for the documentation, since > I'm updating the LyX master and I've already applied your previous > version.Here it goes (below). Also do you think you would be able to merge the driver (corresponding v4 patch follows) in the 3.2 merge window that seems to have just opened? ;-) Cheers! Pawel --- virtio-mmio.orig 2011-10-24 11:17:08.263907000 +0100 +++ virtio-mmio.tex 2011-10-24 13:58:29.752757000 +0100 @@ -59,9 +59,18 @@ \item 0x050 | W | QueueNotify \\ Queue notifier.\\ Writing a queue index to this register notifies the Host that there are new buffers to process in the queue. -\item 0x060 | W | InterruptACK \\ +\item 0x060 | R | InterruptStatus \\ +Interrupt status. \\ +Reading from this register returns a bit mask of interrupts asserted by the device. An interrupt is asserted if the corresponding bit is set, ie. equals one (1). \\ +\begin{itemize} +\item Bit 0 | Used Ring update \\ +This interrupt is asserted when the Host has updated the Used Ring in at least one of the active virtual queues. +\item Bit 1 | Configuration change \\ +This interrupt is asserted when configuration of the device has changed. +\end{itemize} +\item 0x064 | W | InterruptACK \\ Interrupt acknowledge. \\ -Writing to this register notifies the Host that the Guest finished receiving used buffers from the device and therefore serviced an asserted interrupt. Values written to this register are currently not used, but for future extensions it must be set to one (0x1). +Writing to this register notifies the Host that the Guest finished handling interrupts. Every bit of the value clears corresponding bit of the InterruptStatus register. \\ \item 0x070 | RW | Status \\ Device status. \\ Reading from this register returns the current device status flags. \\ @@ -100,8 +109,7 @@ The memory mapped virtio device behaves in the same way as described in p. 2.4 ``Device Operation'', with the following exceptions: \begin{enumerate} \item The device is notified about new buffers available in a queue by writing the queue index to register QueueNum instead of the virtio header in PCI I/O space (p. 2.4.1.4 ``Notifying The Device''). -\item As the memory mapped virtio device is using single, dedicated interrupt signal, its handling is much simpler than in the PCI (MSI-X) case (p. 2.4.2 ``Receiving Used Buffer From The Device''). Therefore all the Guest interrupt handler should do after receiving used buffers is acknowledging the interrupt by writing a value to the InterruptACK register. Currently this value does not carry any meaning, but for future extensions it must be set to one (0x1). -\item The dynamic configuration changes, as described in p. 2.4.3 ``Dealing With Configuration Changes'' are not permitted. +\item The memory mapped virtio device is using single, dedicated interrupt signal. After receiving an interrupt, the driver must read the InterruptStatus register to check what caused the interrupt (see the register description). After the interrupt is handled, the driver must acknowledge it by writing a bit mask corresponding to the serviced interrupt to the InterruptACK register. \end{enumerate} \end{document}
Pawel Moll
2011-Oct-27 02:27 UTC
[PATCH v4] virtio: Add platform bus driver for memory mapped virtio device
This patch, based on virtio PCI driver, adds support for memory
mapped (platform) virtio device. This should allow environments
like qemu to use virtio-based block & network devices even on
platforms without PCI support.
One can define and register a platform device which resources
will describe memory mapped control registers and "mailbox"
interrupt. Such device can be also instantiated using the Device
Tree node with compatible property equal "virtio,mmio".
Cc: Rusty Russell <rusty at rustcorp.com.au>
Cc: Anthony Liguori <aliguori at us.ibm.com>
Cc: Michael S.Tsirkin <mst at redhat.com>
Signed-off-by: Pawel Moll <pawel.moll at arm.com>
---
Changes since v3:
* Dynamic config changes are handled now
* Interrupt acknowledge register moved to 0x064
* Added interrupt status register at 0x060
* Added interrupt flags (VIRTIO_MMIO_INT_VRING & VIRTIO_MMIO_INT_CONFIG)
Changes since v2:
* Fixed bug a bug in vm_find_vqs() error handling code (interrupt was
freed twice)
Changes since v1:
* Added new QueueNumMax register at 0x034, shifting QueueNum,
QueueAlign and QueuePFN by 4 bytes
* Queue page allocation strategy changed
Documentation/devicetree/bindings/virtio/mmio.txt | 17 +
drivers/virtio/Kconfig | 11 +
drivers/virtio/Makefile | 1 +
drivers/virtio/virtio_mmio.c | 479 +++++++++++++++++++++
include/linux/virtio_mmio.h | 111 +++++
5 files changed, 619 insertions(+), 0 deletions(-)
create mode 100644 Documentation/devicetree/bindings/virtio/mmio.txt
create mode 100644 drivers/virtio/virtio_mmio.c
create mode 100644 include/linux/virtio_mmio.h
diff --git a/Documentation/devicetree/bindings/virtio/mmio.txt
b/Documentation/devicetree/bindings/virtio/mmio.txt
new file mode 100644
index 0000000..5069c1b
--- /dev/null
+++ b/Documentation/devicetree/bindings/virtio/mmio.txt
@@ -0,0 +1,17 @@
+* virtio memory mapped device
+
+See http://ozlabs.org/~rusty/virtio-spec/ for more details.
+
+Required properties:
+
+- compatible: "virtio,mmio" compatibility string
+- reg: control registers base address and size including configuration space
+- interrupts: interrupt generated by the device
+
+Example:
+
+ virtio_block at 3000 {
+ compatible = "virtio,mmio";
+ reg = <0x3000 0x100>;
+ interrupts = <41>;
+ }
diff --git a/drivers/virtio/Kconfig b/drivers/virtio/Kconfig
index 57e493b..816ed08 100644
--- a/drivers/virtio/Kconfig
+++ b/drivers/virtio/Kconfig
@@ -35,4 +35,15 @@ config VIRTIO_BALLOON
If unsure, say M.
+ config VIRTIO_MMIO
+ tristate "Platform bus driver for memory mapped virtio devices
(EXPERIMENTAL)"
+ depends on EXPERIMENTAL
+ select VIRTIO
+ select VIRTIO_RING
+ ---help---
+ This drivers provides support for memory mapped virtio
+ platform device driver.
+
+ If unsure, say N.
+
endmenu
diff --git a/drivers/virtio/Makefile b/drivers/virtio/Makefile
index 6738c44..5a4c63c 100644
--- a/drivers/virtio/Makefile
+++ b/drivers/virtio/Makefile
@@ -1,4 +1,5 @@
obj-$(CONFIG_VIRTIO) += virtio.o
obj-$(CONFIG_VIRTIO_RING) += virtio_ring.o
+obj-$(CONFIG_VIRTIO_MMIO) += virtio_mmio.o
obj-$(CONFIG_VIRTIO_PCI) += virtio_pci.o
obj-$(CONFIG_VIRTIO_BALLOON) += virtio_balloon.o
diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c
new file mode 100644
index 0000000..acc5e43
--- /dev/null
+++ b/drivers/virtio/virtio_mmio.c
@@ -0,0 +1,479 @@
+/*
+ * Virtio memory mapped device driver
+ *
+ * Copyright 2011, ARM Ltd.
+ *
+ * This module allows virtio devices to be used over a virtual, memory mapped
+ * platform device.
+ *
+ * Registers layout (all 32-bit wide):
+ *
+ * offset d. name description
+ * ------ -- ---------------- -----------------
+ *
+ * 0x000 R MagicValue Magic value "virt"
+ * 0x004 R Version Device version (current max. 1)
+ * 0x008 R DeviceID Virtio device ID
+ * 0x00c R VendorID Virtio vendor ID
+ *
+ * 0x010 R HostFeatures Features supported by the host
+ * 0x014 W HostFeaturesSel Set of host features to access via HostFeatures
+ *
+ * 0x020 W GuestFeatures Features activated by the guest
+ * 0x024 W GuestFeaturesSel Set of activated features to set via
GuestFeatures
+ * 0x028 W GuestPageSize Size of guest's memory page in bytes
+ *
+ * 0x030 W QueueSel Queue selector
+ * 0x034 R QueueNumMax Maximum size of the currently selected queue
+ * 0x038 W QueueNum Queue size for the currently selected queue
+ * 0x03c W QueueAlign Used Ring alignment for the current queue
+ * 0x040 RW QueuePFN PFN for the currently selected queue
+ *
+ * 0x050 W QueueNotify Queue notifier
+ * 0x060 R InterruptStatus Interrupt status register
+ * 0x060 W InterruptACK Interrupt acknowledge register
+ * 0x070 RW Status Device status register
+ *
+ * 0x100+ RW Device-specific configuration space
+ *
+ * Based on Virtio PCI driver by Anthony Liguori, copyright IBM Corp. 2007
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include <linux/highmem.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/virtio.h>
+#include <linux/virtio_config.h>
+#include <linux/virtio_mmio.h>
+#include <linux/virtio_ring.h>
+
+
+
+/* The alignment to use between consumer and producer parts of vring.
+ * Currently hardcoded to the page size. */
+#define VIRTIO_MMIO_VRING_ALIGN PAGE_SIZE
+
+
+
+#define to_virtio_mmio_device(_plat_dev) \
+ container_of(_plat_dev, struct virtio_mmio_device, vdev)
+
+struct virtio_mmio_device {
+ struct virtio_device vdev;
+ struct platform_device *pdev;
+
+ void __iomem *base;
+ unsigned long version;
+
+ /* a list of queues so we can dispatch IRQs */
+ spinlock_t lock;
+ struct list_head virtqueues;
+};
+
+struct virtio_mmio_vq_info {
+ /* the actual virtqueue */
+ struct virtqueue *vq;
+
+ /* the number of entries in the queue */
+ unsigned int num;
+
+ /* the index of the queue */
+ int queue_index;
+
+ /* the virtual address of the ring queue */
+ void *queue;
+
+ /* the list node for the virtqueues list */
+ struct list_head node;
+};
+
+
+
+/* Configuration interface */
+
+static u32 vm_get_features(struct virtio_device *vdev)
+{
+ struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
+
+ /* TODO: Features > 32 bits */
+ writel(0, vm_dev->base + VIRTIO_MMIO_HOST_FEATURES_SEL);
+
+ return readl(vm_dev->base + VIRTIO_MMIO_HOST_FEATURES);
+}
+
+static void vm_finalize_features(struct virtio_device *vdev)
+{
+ struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
+ int i;
+
+ /* Give virtio_ring a chance to accept features. */
+ vring_transport_features(vdev);
+
+ for (i = 0; i < ARRAY_SIZE(vdev->features); i++) {
+ writel(i, vm_dev->base + VIRTIO_MMIO_GUEST_FEATURES_SET);
+ writel(vdev->features[i],
+ vm_dev->base + VIRTIO_MMIO_GUEST_FEATURES);
+ }
+}
+
+static void vm_get(struct virtio_device *vdev, unsigned offset,
+ void *buf, unsigned len)
+{
+ struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
+ u8 *ptr = buf;
+ int i;
+
+ for (i = 0; i < len; i++)
+ ptr[i] = readb(vm_dev->base + VIRTIO_MMIO_CONFIG + offset + i);
+}
+
+static void vm_set(struct virtio_device *vdev, unsigned offset,
+ const void *buf, unsigned len)
+{
+ struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
+ const u8 *ptr = buf;
+ int i;
+
+ for (i = 0; i < len; i++)
+ writeb(ptr[i], vm_dev->base + VIRTIO_MMIO_CONFIG + offset + i);
+}
+
+static u8 vm_get_status(struct virtio_device *vdev)
+{
+ struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
+
+ return readl(vm_dev->base + VIRTIO_MMIO_STATUS) & 0xff;
+}
+
+static void vm_set_status(struct virtio_device *vdev, u8 status)
+{
+ struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
+
+ /* We should never be setting status to 0. */
+ BUG_ON(status == 0);
+
+ writel(status, vm_dev->base + VIRTIO_MMIO_STATUS);
+}
+
+static void vm_reset(struct virtio_device *vdev)
+{
+ struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
+
+ /* 0 status means a reset. */
+ writel(0, vm_dev->base + VIRTIO_MMIO_STATUS);
+}
+
+
+
+/* Transport interface */
+
+/* the notify function used when creating a virt queue */
+static void vm_notify(struct virtqueue *vq)
+{
+ struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vq->vdev);
+ struct virtio_mmio_vq_info *info = vq->priv;
+
+ /* We write the queue's selector into the notification register to
+ * signal the other end */
+ writel(info->queue_index, vm_dev->base + VIRTIO_MMIO_QUEUE_NOTIFY);
+}
+
+/* Notify all virtqueues on an interrupt. */
+static irqreturn_t vm_interrupt(int irq, void *opaque)
+{
+ struct virtio_mmio_device *vm_dev = opaque;
+ struct virtio_mmio_vq_info *info;
+ struct virtio_driver *vdrv = container_of(vm_dev->vdev.dev.driver,
+ struct virtio_driver, driver);
+ unsigned long status;
+ unsigned long flags;
+ irqreturn_t ret = IRQ_NONE;
+
+ /* Read and acknowledge interrupts */
+ status = readl(vm_dev->base + VIRTIO_MMIO_INTERRUPT_STATUS);
+ writel(status, vm_dev->base + VIRTIO_MMIO_INTERRUPT_ACK);
+
+ if (unlikely(status & VIRTIO_MMIO_INT_CONFIG)
+ && vdrv && vdrv->config_changed) {
+ vdrv->config_changed(&vm_dev->vdev);
+ ret = IRQ_HANDLED;
+ }
+
+ if (likely(status & VIRTIO_MMIO_INT_VRING)) {
+ spin_lock_irqsave(&vm_dev->lock, flags);
+ list_for_each_entry(info, &vm_dev->virtqueues, node)
+ ret |= vring_interrupt(irq, info->vq);
+ spin_unlock_irqrestore(&vm_dev->lock, flags);
+ }
+
+ return ret;
+}
+
+
+
+static void vm_del_vq(struct virtqueue *vq)
+{
+ struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vq->vdev);
+ struct virtio_mmio_vq_info *info = vq->priv;
+ unsigned long flags, size;
+
+ spin_lock_irqsave(&vm_dev->lock, flags);
+ list_del(&info->node);
+ spin_unlock_irqrestore(&vm_dev->lock, flags);
+
+ vring_del_virtqueue(vq);
+
+ /* Select and deactivate the queue */
+ writel(info->queue_index, vm_dev->base + VIRTIO_MMIO_QUEUE_SEL);
+ writel(0, vm_dev->base + VIRTIO_MMIO_QUEUE_PFN);
+
+ size = PAGE_ALIGN(vring_size(info->num, VIRTIO_MMIO_VRING_ALIGN));
+ free_pages_exact(info->queue, size);
+ kfree(info);
+}
+
+static void vm_del_vqs(struct virtio_device *vdev)
+{
+ struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
+ struct virtqueue *vq, *n;
+
+ list_for_each_entry_safe(vq, n, &vdev->vqs, list)
+ vm_del_vq(vq);
+
+ free_irq(platform_get_irq(vm_dev->pdev, 0), vm_dev);
+}
+
+
+
+static struct virtqueue *vm_setup_vq(struct virtio_device *vdev, unsigned
index,
+ void (*callback)(struct virtqueue *vq),
+ const char *name)
+{
+ struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
+ struct virtio_mmio_vq_info *info;
+ struct virtqueue *vq;
+ unsigned long flags, size;
+ int err;
+
+ /* Select the queue we're interested in */
+ writel(index, vm_dev->base + VIRTIO_MMIO_QUEUE_SEL);
+
+ /* Queue shouldn't already be set up. */
+ if (readl(vm_dev->base + VIRTIO_MMIO_QUEUE_PFN)) {
+ err = -ENOENT;
+ goto error_available;
+ }
+
+ /* Allocate and fill out our active queue description */
+ info = kmalloc(sizeof(*info), GFP_KERNEL);
+ if (!info) {
+ err = -ENOMEM;
+ goto error_kmalloc;
+ }
+ info->queue_index = index;
+
+ /* Allocate pages for the queue - start with a queue as big as
+ * possible (limited by maximum size allowed by device), drop down
+ * to a minimal size, just big enough to fit descriptor table
+ * and two rings (which makes it "alignment_size * 2")
+ */
+ info->num = readl(vm_dev->base + VIRTIO_MMIO_QUEUE_NUM_MAX);
+ while (1) {
+ size = PAGE_ALIGN(vring_size(info->num,
+ VIRTIO_MMIO_VRING_ALIGN));
+ /* Already smallest possible allocation? */
+ if (size <= VIRTIO_MMIO_VRING_ALIGN * 2) {
+ err = -ENOMEM;
+ goto error_alloc_pages;
+ }
+
+ info->queue = alloc_pages_exact(size, GFP_KERNEL | __GFP_ZERO);
+ if (info->queue)
+ break;
+
+ info->num /= 2;
+ }
+
+ /* Activate the queue */
+ writel(info->num, vm_dev->base + VIRTIO_MMIO_QUEUE_NUM);
+ writel(VIRTIO_MMIO_VRING_ALIGN,
+ vm_dev->base + VIRTIO_MMIO_QUEUE_ALIGN);
+ writel(virt_to_phys(info->queue) >> PAGE_SHIFT,
+ vm_dev->base + VIRTIO_MMIO_QUEUE_PFN);
+
+ /* Create the vring */
+ vq = vring_new_virtqueue(info->num, VIRTIO_MMIO_VRING_ALIGN,
+ vdev, info->queue, vm_notify, callback, name);
+ if (!vq) {
+ err = -ENOMEM;
+ goto error_new_virtqueue;
+ }
+
+ vq->priv = info;
+ info->vq = vq;
+
+ spin_lock_irqsave(&vm_dev->lock, flags);
+ list_add(&info->node, &vm_dev->virtqueues);
+ spin_unlock_irqrestore(&vm_dev->lock, flags);
+
+ return vq;
+
+error_new_virtqueue:
+ writel(0, vm_dev->base + VIRTIO_MMIO_QUEUE_PFN);
+ free_pages_exact(info->queue, size);
+error_alloc_pages:
+ kfree(info);
+error_kmalloc:
+error_available:
+ return ERR_PTR(err);
+}
+
+static int vm_find_vqs(struct virtio_device *vdev, unsigned nvqs,
+ struct virtqueue *vqs[],
+ vq_callback_t *callbacks[],
+ const char *names[])
+{
+ struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev);
+ unsigned int irq = platform_get_irq(vm_dev->pdev, 0);
+ int i, err;
+
+ err = request_irq(irq, vm_interrupt, IRQF_SHARED,
+ dev_name(&vdev->dev), vm_dev);
+ if (err)
+ return err;
+
+ for (i = 0; i < nvqs; ++i) {
+ vqs[i] = vm_setup_vq(vdev, i, callbacks[i], names[i]);
+ if (IS_ERR(vqs[i])) {
+ vm_del_vqs(vdev);
+ return PTR_ERR(vqs[i]);
+ }
+ }
+
+ return 0;
+}
+
+
+
+static struct virtio_config_ops virtio_mmio_config_ops = {
+ .get = vm_get,
+ .set = vm_set,
+ .get_status = vm_get_status,
+ .set_status = vm_set_status,
+ .reset = vm_reset,
+ .find_vqs = vm_find_vqs,
+ .del_vqs = vm_del_vqs,
+ .get_features = vm_get_features,
+ .finalize_features = vm_finalize_features,
+};
+
+
+
+/* Platform device */
+
+static int __devinit virtio_mmio_probe(struct platform_device *pdev)
+{
+ struct virtio_mmio_device *vm_dev;
+ struct resource *mem;
+ unsigned long magic;
+
+ mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!mem)
+ return -EINVAL;
+
+ if (!devm_request_mem_region(&pdev->dev, mem->start,
+ resource_size(mem), pdev->name))
+ return -EBUSY;
+
+ vm_dev = devm_kzalloc(&pdev->dev, sizeof(*vm_dev), GFP_KERNEL);
+ if (!vm_dev)
+ return -ENOMEM;
+
+ vm_dev->vdev.dev.parent = &pdev->dev;
+ vm_dev->vdev.config = &virtio_mmio_config_ops;
+ vm_dev->pdev = pdev;
+ INIT_LIST_HEAD(&vm_dev->virtqueues);
+ spin_lock_init(&vm_dev->lock);
+
+ vm_dev->base = devm_ioremap(&pdev->dev, mem->start,
resource_size(mem));
+ if (vm_dev->base == NULL)
+ return -EFAULT;
+
+ /* Check magic value */
+ magic = readl(vm_dev->base + VIRTIO_MMIO_MAGIC_VALUE);
+ if (memcmp(&magic, "virt", 4) != 0) {
+ dev_warn(&pdev->dev, "Wrong magic value 0x%08lx!\n", magic);
+ return -ENODEV;
+ }
+
+ /* Check device version */
+ vm_dev->version = readl(vm_dev->base + VIRTIO_MMIO_VERSION);
+ if (vm_dev->version != 1) {
+ dev_err(&pdev->dev, "Version %ld not supported!\n",
+ vm_dev->version);
+ return -ENXIO;
+ }
+
+ vm_dev->vdev.id.device = readl(vm_dev->base + VIRTIO_MMIO_DEVICE_ID);
+ vm_dev->vdev.id.vendor = readl(vm_dev->base + VIRTIO_MMIO_VENDOR_ID);
+
+ writel(PAGE_SIZE, vm_dev->base + VIRTIO_MMIO_GUEST_PAGE_SIZE);
+
+ platform_set_drvdata(pdev, vm_dev);
+
+ return register_virtio_device(&vm_dev->vdev);
+}
+
+static int __devexit virtio_mmio_remove(struct platform_device *pdev)
+{
+ struct virtio_mmio_device *vm_dev = platform_get_drvdata(pdev);
+
+ unregister_virtio_device(&vm_dev->vdev);
+
+ return 0;
+}
+
+
+
+/* Platform driver */
+
+static struct of_device_id virtio_mmio_match[] = {
+ { .compatible = "virtio,mmio", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, virtio_mmio_match);
+
+static struct platform_driver virtio_mmio_driver = {
+ .probe = virtio_mmio_probe,
+ .remove = __devexit_p(virtio_mmio_remove),
+ .driver = {
+ .name = "virtio-mmio",
+ .owner = THIS_MODULE,
+ .of_match_table = virtio_mmio_match,
+ },
+};
+
+static int __init virtio_mmio_init(void)
+{
+ return platform_driver_register(&virtio_mmio_driver);
+}
+
+static void __exit virtio_mmio_exit(void)
+{
+ platform_driver_unregister(&virtio_mmio_driver);
+}
+
+module_init(virtio_mmio_init);
+module_exit(virtio_mmio_exit);
+
+MODULE_AUTHOR("Pawel Moll <pawel.moll at arm.com>");
+MODULE_DESCRIPTION("Platform bus driver for memory mapped virtio
devices");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/virtio_mmio.h b/include/linux/virtio_mmio.h
new file mode 100644
index 0000000..27c7ede
--- /dev/null
+++ b/include/linux/virtio_mmio.h
@@ -0,0 +1,111 @@
+/*
+ * Virtio platform device driver
+ *
+ * Copyright 2011, ARM Ltd.
+ *
+ * Based on Virtio PCI driver by Anthony Liguori, copyright IBM Corp. 2007
+ *
+ * This header is BSD licensed so anyone can use the definitions to implement
+ * compatible drivers/servers.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of IBM nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS
IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef _LINUX_VIRTIO_MMIO_H
+#define _LINUX_VIRTIO_MMIO_H
+
+/*
+ * Control registers
+ */
+
+/* Magic value ("virt" string) - Read Only */
+#define VIRTIO_MMIO_MAGIC_VALUE 0x000
+
+/* Virtio device version - Read Only */
+#define VIRTIO_MMIO_VERSION 0x004
+
+/* Virtio device ID - Read Only */
+#define VIRTIO_MMIO_DEVICE_ID 0x008
+
+/* Virtio vendor ID - Read Only */
+#define VIRTIO_MMIO_VENDOR_ID 0x00c
+
+/* Bitmask of the features supported by the host
+ * (32 bits per set) - Read Only */
+#define VIRTIO_MMIO_HOST_FEATURES 0x010
+
+/* Host features set selector - Write Only */
+#define VIRTIO_MMIO_HOST_FEATURES_SEL 0x014
+
+/* Bitmask of features activated by the guest
+ * (32 bits per set) - Write Only */
+#define VIRTIO_MMIO_GUEST_FEATURES 0x020
+
+/* Activated features set selector - Write Only */
+#define VIRTIO_MMIO_GUEST_FEATURES_SET 0x024
+
+/* Guest's memory page size in bytes - Write Only */
+#define VIRTIO_MMIO_GUEST_PAGE_SIZE 0x028
+
+/* Queue selector - Write Only */
+#define VIRTIO_MMIO_QUEUE_SEL 0x030
+
+/* Maximum size of the currently selected queue - Read Only */
+#define VIRTIO_MMIO_QUEUE_NUM_MAX 0x034
+
+/* Queue size for the currently selected queue - Write Only */
+#define VIRTIO_MMIO_QUEUE_NUM 0x038
+
+/* Used Ring alignment for the currently selected queue - Write Only */
+#define VIRTIO_MMIO_QUEUE_ALIGN 0x03c
+
+/* Guest's PFN for the currently selected queue - Read Write */
+#define VIRTIO_MMIO_QUEUE_PFN 0x040
+
+/* Queue notifier - Write Only */
+#define VIRTIO_MMIO_QUEUE_NOTIFY 0x050
+
+/* Interrupt status - Read Only */
+#define VIRTIO_MMIO_INTERRUPT_STATUS 0x060
+
+/* Interrupt acknowledge - Write Only */
+#define VIRTIO_MMIO_INTERRUPT_ACK 0x064
+
+/* Device status register - Read Write */
+#define VIRTIO_MMIO_STATUS 0x070
+
+/* The config space is defined by each driver as
+ * the per-driver configuration space - Read Write */
+#define VIRTIO_MMIO_CONFIG 0x100
+
+
+
+/*
+ * Interrupt flags (re: interrupt status & acknowledge registers)
+ */
+
+#define VIRTIO_MMIO_INT_VRING (1 << 0)
+#define VIRTIO_MMIO_INT_CONFIG (1 << 1)
+
+#endif
--
1.6.3.3
Apparently Analagous Threads
- [PATCH v3] virtio: Add platform bus driver for memory mapped virtio device
- [RFC] virtio-mmio: Update the device to OASIS spec version
- [RFC] virtio-mmio: Update the device to OASIS spec version
- [PATCH v2] virtio-mmio: Update the device to OASIS spec version
- [PATCH v2] virtio-mmio: Update the device to OASIS spec version