diff --git a/drivers/virtio/Kconfig b/drivers/virtio/Kconfig
index 82fc5368317b6eca70fe7b31a78818872d37bb34..4f9a11b6ef2f080382e4432a5a055852a6f43b8d 100644
--- a/drivers/virtio/Kconfig
+++ b/drivers/virtio/Kconfig
@@ -22,4 +22,11 @@ config VIRTIO
This option is selected by any driver which implements the virtio
transport, such as CONFIG_VIRTIO_MMIO or CONFIG_VIRTIO_PCI.
+config VIRTIO_MMIO
+ bool "Platform bus driver for memory mapped virtio devices"
+ select VIRTIO
+ help
+ This driver provides support for memory mapped virtio
+ platform device driver.
+
endmenu
diff --git a/drivers/virtio/Makefile b/drivers/virtio/Makefile
index 17d264a7718ddb9d06c771d865b0f69bc3b290f0..2e487854a24125d09ffd3dc93a1e1bae5a151093 100644
--- a/drivers/virtio/Makefile
+++ b/drivers/virtio/Makefile
@@ -4,3 +4,4 @@
# Copyright (C) 2018, Bin Meng <bmeng.cn@gmail.com>
obj-y += virtio-uclass.o virtio_ring.o
+obj-$(CONFIG_VIRTIO_MMIO) += virtio_mmio.o
diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c
new file mode 100644
index 0000000000000000000000000000000000000000..7b738703b827b10a09bdd72afa23b9605837b369
--- /dev/null
+++ b/drivers/virtio/virtio_mmio.c
@@ -0,0 +1,413 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2018, Tuomas Tynkkynen <tuomas.tynkkynen@iki.fi>
+ * Copyright (C) 2018, Bin Meng <bmeng.cn@gmail.com>
+ *
+ * VirtIO memory-maped I/O transport driver
+ * Ported from Linux drivers/virtio/virtio_mmio.c
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <virtio_types.h>
+#include <virtio.h>
+#include <virtio_ring.h>
+#include <linux/compat.h>
+#include <linux/io.h>
+#include "virtio_mmio.h"
+
+static int virtio_mmio_get_config(struct udevice *udev, unsigned int offset,
+ void *buf, unsigned int len)
+{
+ struct virtio_mmio_priv *priv = dev_get_priv(udev);
+ void __iomem *base = priv->base + VIRTIO_MMIO_CONFIG;
+ u8 b;
+ __le16 w;
+ __le32 l;
+
+ if (priv->version == 1) {
+ u8 *ptr = buf;
+ int i;
+
+ for (i = 0; i < len; i++)
+ ptr[i] = readb(base + offset + i);
+
+ return 0;
+ }
+
+ switch (len) {
+ case 1:
+ b = readb(base + offset);
+ memcpy(buf, &b, sizeof(b));
+ break;
+ case 2:
+ w = cpu_to_le16(readw(base + offset));
+ memcpy(buf, &w, sizeof(w));
+ break;
+ case 4:
+ l = cpu_to_le32(readl(base + offset));
+ memcpy(buf, &l, sizeof(l));
+ break;
+ case 8:
+ l = cpu_to_le32(readl(base + offset));
+ memcpy(buf, &l, sizeof(l));
+ l = cpu_to_le32(readl(base + offset + sizeof(l)));
+ memcpy(buf + sizeof(l), &l, sizeof(l));
+ break;
+ default:
+ WARN_ON(true);
+ }
+
+ return 0;
+}
+
+static int virtio_mmio_set_config(struct udevice *udev, unsigned int offset,
+ const void *buf, unsigned int len)
+{
+ struct virtio_mmio_priv *priv = dev_get_priv(udev);
+ void __iomem *base = priv->base + VIRTIO_MMIO_CONFIG;
+ u8 b;
+ __le16 w;
+ __le32 l;
+
+ if (priv->version == 1) {
+ const u8 *ptr = buf;
+ int i;
+
+ for (i = 0; i < len; i++)
+ writeb(ptr[i], base + offset + i);
+
+ return 0;
+ }
+
+ switch (len) {
+ case 1:
+ memcpy(&b, buf, sizeof(b));
+ writeb(b, base + offset);
+ break;
+ case 2:
+ memcpy(&w, buf, sizeof(w));
+ writew(le16_to_cpu(w), base + offset);
+ break;
+ case 4:
+ memcpy(&l, buf, sizeof(l));
+ writel(le32_to_cpu(l), base + offset);
+ break;
+ case 8:
+ memcpy(&l, buf, sizeof(l));
+ writel(le32_to_cpu(l), base + offset);
+ memcpy(&l, buf + sizeof(l), sizeof(l));
+ writel(le32_to_cpu(l), base + offset + sizeof(l));
+ break;
+ default:
+ WARN_ON(true);
+ }
+
+ return 0;
+}
+
+static int virtio_mmio_generation(struct udevice *udev, u32 *counter)
+{
+ struct virtio_mmio_priv *priv = dev_get_priv(udev);
+
+ if (priv->version == 1)
+ *counter = 0;
+ else
+ *counter = readl(priv->base + VIRTIO_MMIO_CONFIG_GENERATION);
+
+ return 0;
+}
+
+static int virtio_mmio_get_status(struct udevice *udev, u8 *status)
+{
+ struct virtio_mmio_priv *priv = dev_get_priv(udev);
+
+ *status = readl(priv->base + VIRTIO_MMIO_STATUS) & 0xff;
+
+ return 0;
+}
+
+static int virtio_mmio_set_status(struct udevice *udev, u8 status)
+{
+ struct virtio_mmio_priv *priv = dev_get_priv(udev);
+
+ /* We should never be setting status to 0 */
+ WARN_ON(status == 0);
+
+ writel(status, priv->base + VIRTIO_MMIO_STATUS);
+
+ return 0;
+}
+
+static int virtio_mmio_reset(struct udevice *udev)
+{
+ struct virtio_mmio_priv *priv = dev_get_priv(udev);
+
+ /* 0 status means a reset */
+ writel(0, priv->base + VIRTIO_MMIO_STATUS);
+
+ return 0;
+}
+
+static int virtio_mmio_get_features(struct udevice *udev, u64 *features)
+{
+ struct virtio_mmio_priv *priv = dev_get_priv(udev);
+
+ writel(1, priv->base + VIRTIO_MMIO_DEVICE_FEATURES_SEL);
+ *features = readl(priv->base + VIRTIO_MMIO_DEVICE_FEATURES);
+ *features <<= 32;
+
+ writel(0, priv->base + VIRTIO_MMIO_DEVICE_FEATURES_SEL);
+ *features |= readl(priv->base + VIRTIO_MMIO_DEVICE_FEATURES);
+
+ return 0;
+}
+
+static int virtio_mmio_set_features(struct udevice *udev)
+{
+ struct virtio_mmio_priv *priv = dev_get_priv(udev);
+ struct virtio_dev_priv *uc_priv = dev_get_uclass_priv(udev);
+
+ /* Make sure there is are no mixed devices */
+ if (priv->version == 2 && uc_priv->legacy) {
+ debug("New virtio-mmio devices (version 2) must provide VIRTIO_F_VERSION_1 feature!\n");
+ return -EINVAL;
+ }
+
+ writel(1, priv->base + VIRTIO_MMIO_DRIVER_FEATURES_SEL);
+ writel((u32)(uc_priv->features >> 32),
+ priv->base + VIRTIO_MMIO_DRIVER_FEATURES);
+
+ writel(0, priv->base + VIRTIO_MMIO_DRIVER_FEATURES_SEL);
+ writel((u32)uc_priv->features,
+ priv->base + VIRTIO_MMIO_DRIVER_FEATURES);
+
+ return 0;
+}
+
+static struct virtqueue *virtio_mmio_setup_vq(struct udevice *udev,
+ unsigned int index)
+{
+ struct virtio_mmio_priv *priv = dev_get_priv(udev);
+ struct virtqueue *vq;
+ unsigned int num;
+ int err;
+
+ /* Select the queue we're interested in */
+ writel(index, priv->base + VIRTIO_MMIO_QUEUE_SEL);
+
+ /* Queue shouldn't already be set up */
+ if (readl(priv->base + (priv->version == 1 ?
+ VIRTIO_MMIO_QUEUE_PFN : VIRTIO_MMIO_QUEUE_READY))) {
+ err = -ENOENT;
+ goto error_available;
+ }
+
+ num = readl(priv->base + VIRTIO_MMIO_QUEUE_NUM_MAX);
+ if (num == 0) {
+ err = -ENOENT;
+ goto error_new_virtqueue;
+ }
+
+ /* Create the vring */
+ vq = vring_create_virtqueue(index, num, VIRTIO_MMIO_VRING_ALIGN, udev);
+ if (!vq) {
+ err = -ENOMEM;
+ goto error_new_virtqueue;
+ }
+
+ /* Activate the queue */
+ writel(virtqueue_get_vring_size(vq),
+ priv->base + VIRTIO_MMIO_QUEUE_NUM);
+ if (priv->version == 1) {
+ u64 q_pfn = virtqueue_get_desc_addr(vq) >> PAGE_SHIFT;
+
+ /*
+ * virtio-mmio v1 uses a 32bit QUEUE PFN. If we have something
+ * that doesn't fit in 32bit, fail the setup rather than
+ * pretending to be successful.
+ */
+ if (q_pfn >> 32) {
+ debug("platform bug: legacy virtio-mmio must not be used with RAM above 0x%llxGB\n",
+ 0x1ULL << (32 + PAGE_SHIFT - 30));
+ err = -E2BIG;
+ goto error_bad_pfn;
+ }
+
+ writel(PAGE_SIZE, priv->base + VIRTIO_MMIO_QUEUE_ALIGN);
+ writel(q_pfn, priv->base + VIRTIO_MMIO_QUEUE_PFN);
+ } else {
+ u64 addr;
+
+ addr = virtqueue_get_desc_addr(vq);
+ writel((u32)addr, priv->base + VIRTIO_MMIO_QUEUE_DESC_LOW);
+ writel((u32)(addr >> 32),
+ priv->base + VIRTIO_MMIO_QUEUE_DESC_HIGH);
+
+ addr = virtqueue_get_avail_addr(vq);
+ writel((u32)addr, priv->base + VIRTIO_MMIO_QUEUE_AVAIL_LOW);
+ writel((u32)(addr >> 32),
+ priv->base + VIRTIO_MMIO_QUEUE_AVAIL_HIGH);
+
+ addr = virtqueue_get_used_addr(vq);
+ writel((u32)addr, priv->base + VIRTIO_MMIO_QUEUE_USED_LOW);
+ writel((u32)(addr >> 32),
+ priv->base + VIRTIO_MMIO_QUEUE_USED_HIGH);
+
+ writel(1, priv->base + VIRTIO_MMIO_QUEUE_READY);
+ }
+
+ return vq;
+
+error_bad_pfn:
+ vring_del_virtqueue(vq);
+
+error_new_virtqueue:
+ if (priv->version == 1) {
+ writel(0, priv->base + VIRTIO_MMIO_QUEUE_PFN);
+ } else {
+ writel(0, priv->base + VIRTIO_MMIO_QUEUE_READY);
+ WARN_ON(readl(priv->base + VIRTIO_MMIO_QUEUE_READY));
+ }
+
+error_available:
+ return ERR_PTR(err);
+}
+
+static void virtio_mmio_del_vq(struct virtqueue *vq)
+{
+ struct virtio_mmio_priv *priv = dev_get_priv(vq->vdev);
+ unsigned int index = vq->index;
+
+ /* Select and deactivate the queue */
+ writel(index, priv->base + VIRTIO_MMIO_QUEUE_SEL);
+ if (priv->version == 1) {
+ writel(0, priv->base + VIRTIO_MMIO_QUEUE_PFN);
+ } else {
+ writel(0, priv->base + VIRTIO_MMIO_QUEUE_READY);
+ WARN_ON(readl(priv->base + VIRTIO_MMIO_QUEUE_READY));
+ }
+
+ vring_del_virtqueue(vq);
+}
+
+static int virtio_mmio_del_vqs(struct udevice *udev)
+{
+ struct virtio_dev_priv *uc_priv = dev_get_uclass_priv(udev);
+ struct virtqueue *vq, *n;
+
+ list_for_each_entry_safe(vq, n, &uc_priv->vqs, list)
+ virtio_mmio_del_vq(vq);
+
+ return 0;
+}
+
+static int virtio_mmio_find_vqs(struct udevice *udev, unsigned int nvqs,
+ struct virtqueue *vqs[])
+{
+ int i;
+
+ for (i = 0; i < nvqs; ++i) {
+ vqs[i] = virtio_mmio_setup_vq(udev, i);
+ if (IS_ERR(vqs[i])) {
+ virtio_mmio_del_vqs(udev);
+ return PTR_ERR(vqs[i]);
+ }
+ }
+
+ return 0;
+}
+
+static int virtio_mmio_notify(struct udevice *udev, struct virtqueue *vq)
+{
+ struct virtio_mmio_priv *priv = dev_get_priv(udev);
+
+ /*
+ * We write the queue's selector into the notification register
+ * to signal the other end
+ */
+ writel(vq->index, priv->base + VIRTIO_MMIO_QUEUE_NOTIFY);
+
+ return 0;
+}
+
+static int virtio_mmio_ofdata_to_platdata(struct udevice *udev)
+{
+ struct virtio_mmio_priv *priv = dev_get_priv(udev);
+
+ priv->base = (void __iomem *)(ulong)dev_read_addr(udev);
+ if (priv->base == (void __iomem *)FDT_ADDR_T_NONE)
+ return -EINVAL;
+
+ return 0;
+}
+
+static int virtio_mmio_probe(struct udevice *udev)
+{
+ struct virtio_mmio_priv *priv = dev_get_priv(udev);
+ struct virtio_dev_priv *uc_priv = dev_get_uclass_priv(udev);
+ u32 magic;
+
+ /* Check magic value */
+ magic = readl(priv->base + VIRTIO_MMIO_MAGIC_VALUE);
+ if (magic != ('v' | 'i' << 8 | 'r' << 16 | 't' << 24)) {
+ debug("(%s): wrong magic value 0x%08x!\n", udev->name, magic);
+ return 0;
+ }
+
+ /* Check device version */
+ priv->version = readl(priv->base + VIRTIO_MMIO_VERSION);
+ if (priv->version < 1 || priv->version > 2) {
+ debug("(%s): version %d not supported!\n",
+ udev->name, priv->version);
+ return 0;
+ }
+
+ /* Check devicd ID */
+ uc_priv->device = readl(priv->base + VIRTIO_MMIO_DEVICE_ID);
+ if (uc_priv->device == 0) {
+ /*
+ * virtio-mmio device with an ID 0 is a (dummy) placeholder
+ * with no function. End probing now with no error reported.
+ */
+ return 0;
+ }
+ uc_priv->vendor = readl(priv->base + VIRTIO_MMIO_VENDOR_ID);
+
+ if (priv->version == 1)
+ writel(PAGE_SIZE, priv->base + VIRTIO_MMIO_GUEST_PAGE_SIZE);
+
+ debug("(%s): device (%d) vendor (%08x) version (%d)\n", udev->name,
+ uc_priv->device, uc_priv->vendor, priv->version);
+
+ return 0;
+}
+
+static const struct dm_virtio_ops virtio_mmio_ops = {
+ .get_config = virtio_mmio_get_config,
+ .set_config = virtio_mmio_set_config,
+ .generation = virtio_mmio_generation,
+ .get_status = virtio_mmio_get_status,
+ .set_status = virtio_mmio_set_status,
+ .reset = virtio_mmio_reset,
+ .get_features = virtio_mmio_get_features,
+ .set_features = virtio_mmio_set_features,
+ .find_vqs = virtio_mmio_find_vqs,
+ .del_vqs = virtio_mmio_del_vqs,
+ .notify = virtio_mmio_notify,
+};
+
+static const struct udevice_id virtio_mmio_ids[] = {
+ { .compatible = "virtio,mmio" },
+ { }
+};
+
+U_BOOT_DRIVER(virtio_mmio) = {
+ .name = "virtio-mmio",
+ .id = UCLASS_VIRTIO,
+ .of_match = virtio_mmio_ids,
+ .ops = &virtio_mmio_ops,
+ .probe = virtio_mmio_probe,
+ .ofdata_to_platdata = virtio_mmio_ofdata_to_platdata,
+ .priv_auto_alloc_size = sizeof(struct virtio_mmio_priv),
+};
diff --git a/drivers/virtio/virtio_mmio.h b/drivers/virtio/virtio_mmio.h
new file mode 100644
index 0000000000000000000000000000000000000000..b3408828a5926d07d8063e035764c30fdbc348ae
--- /dev/null
+++ b/drivers/virtio/virtio_mmio.h
@@ -0,0 +1,129 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (C) 2018, Tuomas Tynkkynen <tuomas.tynkkynen@iki.fi>
+ * Copyright (C) 2018, Bin Meng <bmeng.cn@gmail.com>
+ *
+ * From Linux kernel include/uapi/linux/virtio_mmio.h
+ */
+
+#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 device (host)
+ * (32 bits per set) - Read Only
+ */
+#define VIRTIO_MMIO_DEVICE_FEATURES 0x010
+
+/* Device (host) features set selector - Write Only */
+#define VIRTIO_MMIO_DEVICE_FEATURES_SEL 0x014
+
+/*
+ * Bitmask of features activated by the driver (guest)
+ * (32 bits per set) - Write Only
+ */
+#define VIRTIO_MMIO_DRIVER_FEATURES 0x020
+
+/* Activated features set selector - Write Only */
+#define VIRTIO_MMIO_DRIVER_FEATURES_SEL 0x024
+
+#ifndef VIRTIO_MMIO_NO_LEGACY /* LEGACY DEVICES ONLY! */
+
+/* Guest's memory page size in bytes - Write Only */
+#define VIRTIO_MMIO_GUEST_PAGE_SIZE 0x028
+
+#endif
+
+/* 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
+
+#ifndef VIRTIO_MMIO_NO_LEGACY /* LEGACY DEVICES ONLY! */
+
+/* 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
+
+#endif
+
+/* Ready bit for the currently selected queue - Read Write */
+#define VIRTIO_MMIO_QUEUE_READY 0x044
+
+/* 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
+
+/* Selected queue's Descriptor Table address, 64 bits in two halves */
+#define VIRTIO_MMIO_QUEUE_DESC_LOW 0x080
+#define VIRTIO_MMIO_QUEUE_DESC_HIGH 0x084
+
+/* Selected queue's Available Ring address, 64 bits in two halves */
+#define VIRTIO_MMIO_QUEUE_AVAIL_LOW 0x090
+#define VIRTIO_MMIO_QUEUE_AVAIL_HIGH 0x094
+
+/* Selected queue's Used Ring address, 64 bits in two halves */
+#define VIRTIO_MMIO_QUEUE_USED_LOW 0x0a0
+#define VIRTIO_MMIO_QUEUE_USED_HIGH 0x0a4
+
+/* Configuration atomicity value */
+#define VIRTIO_MMIO_CONFIG_GENERATION 0x0fc
+
+/*
+ * 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 BIT(0)
+#define VIRTIO_MMIO_INT_CONFIG BIT(1)
+
+/*
+ * The alignment to use between consumer and producer parts of vring.
+ * Currently hardcoded to the page size.
+ */
+#define PAGE_SHIFT 12
+#define VIRTIO_MMIO_VRING_ALIGN PAGE_SIZE
+
+/**
+ * virtio mmio transport driver private data
+ *
+ * @base: mmio transport device register base
+ * @version: mmio transport device version
+ */
+struct virtio_mmio_priv {
+ void __iomem *base;
+ u32 version;
+};
+
+#endif /* _LINUX_VIRTIO_MMIO_H */