--- /dev/null
+/*
+ * 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@arm.com>");
+MODULE_DESCRIPTION("Platform bus driver for memory mapped virtio devices");
+MODULE_LICENSE("GPL");
--- /dev/null
+/*
+ * 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
git.openpandora.org / pandora-kernel.git / commitdiff