diff options
Diffstat (limited to 'drivers/virtio/virtio_mmio.c')
-rw-r--r-- | drivers/virtio/virtio_mmio.c | 413 |
1 files changed, 413 insertions, 0 deletions
diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c new file mode 100644 index 00000000000..7b738703b82 --- /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), +}; |