blob: 78c15c821b4edabb0a74c01b30f0537ce021648c [file] [log] [blame]
// 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 <log.h>
#include <virtio_types.h>
#include <virtio.h>
#include <virtio_ring.h>
#include <linux/bug.h>
#include <linux/compat.h>
#include <linux/err.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_of_to_plat(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 device 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,
.of_to_plat = virtio_mmio_of_to_plat,
.priv_auto = sizeof(struct virtio_mmio_priv),
};