| // 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 is a virtualization standard for network and disk device drivers |
| * where just the guest's device driver "knows" it is running in a virtual |
| * environment, and cooperates with the hypervisor. This enables guests to |
| * get high performance network and disk operations, and gives most of the |
| * performance benefits of paravirtualization. In the U-Boot case, the guest |
| * is U-Boot itself, while the virtual environment are normally QEMU targets |
| * like ARM, RISC-V and x86. |
| * |
| * See http://docs.oasis-open.org/virtio/virtio/v1.0/virtio-v1.0.pdf for |
| * the VirtIO specification v1.0. |
| */ |
| |
| #define LOG_CATEGORY UCLASS_VIRTIO |
| |
| #include <common.h> |
| #include <dm.h> |
| #include <log.h> |
| #include <malloc.h> |
| #include <virtio_types.h> |
| #include <virtio.h> |
| #include <dm/lists.h> |
| #include <linux/bug.h> |
| |
| static const char *const virtio_drv_name[VIRTIO_ID_MAX_NUM] = { |
| [VIRTIO_ID_NET] = VIRTIO_NET_DRV_NAME, |
| [VIRTIO_ID_BLOCK] = VIRTIO_BLK_DRV_NAME, |
| [VIRTIO_ID_RNG] = VIRTIO_RNG_DRV_NAME, |
| }; |
| |
| int virtio_get_config(struct udevice *vdev, unsigned int offset, |
| void *buf, unsigned int len) |
| { |
| struct dm_virtio_ops *ops; |
| |
| ops = virtio_get_ops(vdev->parent); |
| |
| return ops->get_config(vdev->parent, offset, buf, len); |
| } |
| |
| int virtio_set_config(struct udevice *vdev, unsigned int offset, |
| void *buf, unsigned int len) |
| { |
| struct dm_virtio_ops *ops; |
| |
| ops = virtio_get_ops(vdev->parent); |
| |
| return ops->set_config(vdev->parent, offset, buf, len); |
| } |
| |
| int virtio_generation(struct udevice *vdev, u32 *counter) |
| { |
| struct dm_virtio_ops *ops; |
| |
| ops = virtio_get_ops(vdev->parent); |
| if (!ops->generation) |
| return -ENOSYS; |
| |
| return ops->generation(vdev->parent, counter); |
| } |
| |
| int virtio_get_status(struct udevice *vdev, u8 *status) |
| { |
| struct dm_virtio_ops *ops; |
| |
| ops = virtio_get_ops(vdev->parent); |
| |
| return ops->get_status(vdev->parent, status); |
| } |
| |
| int virtio_set_status(struct udevice *vdev, u8 status) |
| { |
| struct dm_virtio_ops *ops; |
| |
| ops = virtio_get_ops(vdev->parent); |
| |
| return ops->set_status(vdev->parent, status); |
| } |
| |
| int virtio_reset(struct udevice *vdev) |
| { |
| struct dm_virtio_ops *ops; |
| |
| ops = virtio_get_ops(vdev->parent); |
| |
| return ops->reset(vdev->parent); |
| } |
| |
| int virtio_get_features(struct udevice *vdev, u64 *features) |
| { |
| struct dm_virtio_ops *ops; |
| |
| ops = virtio_get_ops(vdev->parent); |
| |
| return ops->get_features(vdev->parent, features); |
| } |
| |
| int virtio_set_features(struct udevice *vdev) |
| { |
| struct dm_virtio_ops *ops; |
| |
| ops = virtio_get_ops(vdev->parent); |
| |
| return ops->set_features(vdev->parent); |
| } |
| |
| int virtio_find_vqs(struct udevice *vdev, unsigned int nvqs, |
| struct virtqueue *vqs[]) |
| { |
| struct dm_virtio_ops *ops; |
| |
| ops = virtio_get_ops(vdev->parent); |
| |
| return ops->find_vqs(vdev->parent, nvqs, vqs); |
| } |
| |
| int virtio_del_vqs(struct udevice *vdev) |
| { |
| struct dm_virtio_ops *ops; |
| |
| ops = virtio_get_ops(vdev->parent); |
| |
| return ops->del_vqs(vdev->parent); |
| } |
| |
| int virtio_notify(struct udevice *vdev, struct virtqueue *vq) |
| { |
| struct dm_virtio_ops *ops; |
| |
| ops = virtio_get_ops(vdev->parent); |
| |
| return ops->notify(vdev->parent, vq); |
| } |
| |
| void virtio_add_status(struct udevice *vdev, u8 status) |
| { |
| u8 old; |
| |
| if (!virtio_get_status(vdev, &old)) |
| virtio_set_status(vdev, old | status); |
| } |
| |
| int virtio_finalize_features(struct udevice *vdev) |
| { |
| struct virtio_dev_priv *uc_priv = dev_get_uclass_priv(vdev->parent); |
| u8 status; |
| int ret; |
| |
| ret = virtio_set_features(vdev); |
| if (ret) |
| return ret; |
| |
| if (uc_priv->legacy) |
| return 0; |
| |
| virtio_add_status(vdev, VIRTIO_CONFIG_S_FEATURES_OK); |
| ret = virtio_get_status(vdev, &status); |
| if (ret) |
| return ret; |
| if (!(status & VIRTIO_CONFIG_S_FEATURES_OK)) { |
| debug("(%s): device refuses features %x\n", vdev->name, status); |
| return -ENODEV; |
| } |
| |
| return 0; |
| } |
| |
| void virtio_driver_features_init(struct virtio_dev_priv *priv, |
| const u32 *feature, |
| u32 feature_size, |
| const u32 *feature_legacy, |
| u32 feature_legacy_size) |
| { |
| priv->feature_table = feature; |
| priv->feature_table_size = feature_size; |
| priv->feature_table_legacy = feature_legacy; |
| priv->feature_table_size_legacy = feature_legacy_size; |
| } |
| |
| int virtio_init(void) |
| { |
| /* Enumerate all known virtio devices */ |
| return uclass_probe_all(UCLASS_VIRTIO); |
| } |
| |
| static int virtio_uclass_pre_probe(struct udevice *udev) |
| { |
| struct dm_virtio_ops *ops; |
| |
| ops = (struct dm_virtio_ops *)(udev->driver->ops); |
| |
| /* |
| * Check virtio transport driver ops here so that we don't need |
| * check these ops each time when the virtio_xxx APIs are called. |
| * |
| * Only generation op is optional. All other ops are must-have. |
| */ |
| if (!ops->get_config || !ops->set_config || |
| !ops->get_status || !ops->set_status || |
| !ops->get_features || !ops->set_features || |
| !ops->find_vqs || !ops->del_vqs || |
| !ops->reset || !ops->notify) |
| return -ENOENT; |
| |
| return 0; |
| } |
| |
| static int virtio_uclass_post_probe(struct udevice *udev) |
| { |
| struct virtio_dev_priv *uc_priv = dev_get_uclass_priv(udev); |
| char dev_name[30], *str; |
| struct udevice *vdev; |
| int ret; |
| |
| if (uc_priv->device >= VIRTIO_ID_MAX_NUM) { |
| debug("(%s): virtio device ID %d exceeds maximum num\n", |
| udev->name, uc_priv->device); |
| return 0; |
| } |
| |
| if (!virtio_drv_name[uc_priv->device]) { |
| debug("(%s): underlying virtio device driver unavailable\n", |
| udev->name); |
| return 0; |
| } |
| |
| snprintf(dev_name, sizeof(dev_name), "%s#%d", |
| virtio_drv_name[uc_priv->device], dev_seq(udev)); |
| str = strdup(dev_name); |
| if (!str) |
| return -ENOMEM; |
| |
| ret = device_bind_driver(udev, virtio_drv_name[uc_priv->device], |
| str, &vdev); |
| if (ret == -ENOENT) { |
| debug("(%s): no driver configured\n", udev->name); |
| return 0; |
| } |
| if (ret) { |
| free(str); |
| return ret; |
| } |
| device_set_name_alloced(vdev); |
| |
| INIT_LIST_HEAD(&uc_priv->vqs); |
| |
| return 0; |
| } |
| |
| static int virtio_uclass_child_post_bind(struct udevice *vdev) |
| { |
| /* Acknowledge that we've seen the device */ |
| virtio_add_status(vdev, VIRTIO_CONFIG_S_ACKNOWLEDGE); |
| |
| return 0; |
| } |
| |
| static int virtio_uclass_child_pre_probe(struct udevice *vdev) |
| { |
| struct virtio_dev_priv *uc_priv = dev_get_uclass_priv(vdev->parent); |
| u64 device_features; |
| u64 driver_features; |
| u64 driver_features_legacy; |
| int i; |
| int ret; |
| |
| /* |
| * Save the real virtio device (eg: virtio-net, virtio-blk) to |
| * the transport (parent) device's uclass priv for future use. |
| */ |
| uc_priv->vdev = vdev; |
| |
| /* |
| * We always start by resetting the device, in case a previous driver |
| * messed it up. This also tests that code path a little. |
| */ |
| ret = virtio_reset(vdev); |
| if (ret) |
| goto err; |
| |
| /* We have a driver! */ |
| virtio_add_status(vdev, VIRTIO_CONFIG_S_DRIVER); |
| |
| /* Figure out what features the device supports */ |
| virtio_get_features(vdev, &device_features); |
| debug("(%s) plain device features supported %016llx\n", |
| vdev->name, device_features); |
| if (!(device_features & (1ULL << VIRTIO_F_VERSION_1))) |
| uc_priv->legacy = true; |
| |
| /* Figure out what features the driver supports */ |
| driver_features = 0; |
| for (i = 0; i < uc_priv->feature_table_size; i++) { |
| unsigned int f = uc_priv->feature_table[i]; |
| |
| WARN_ON(f >= 64); |
| driver_features |= (1ULL << f); |
| } |
| |
| /* Some drivers have a separate feature table for virtio v1.0 */ |
| if (uc_priv->feature_table_legacy) { |
| driver_features_legacy = 0; |
| for (i = 0; i < uc_priv->feature_table_size_legacy; i++) { |
| unsigned int f = uc_priv->feature_table_legacy[i]; |
| |
| WARN_ON(f >= 64); |
| driver_features_legacy |= (1ULL << f); |
| } |
| } else { |
| driver_features_legacy = driver_features; |
| } |
| |
| if (uc_priv->legacy) { |
| debug("(%s): legacy virtio device\n", vdev->name); |
| uc_priv->features = driver_features_legacy & device_features; |
| } else { |
| debug("(%s): v1.0 complaint virtio device\n", vdev->name); |
| uc_priv->features = driver_features & device_features; |
| } |
| |
| /* Transport features always preserved to pass to finalize_features */ |
| for (i = VIRTIO_TRANSPORT_F_START; i < VIRTIO_TRANSPORT_F_END; i++) |
| if ((device_features & (1ULL << i)) && |
| (i == VIRTIO_F_VERSION_1)) |
| __virtio_set_bit(vdev->parent, i); |
| |
| debug("(%s) final negotiated features supported %016llx\n", |
| vdev->name, uc_priv->features); |
| ret = virtio_finalize_features(vdev); |
| if (ret) |
| goto err; |
| |
| return 0; |
| |
| err: |
| virtio_add_status(vdev, VIRTIO_CONFIG_S_FAILED); |
| return ret; |
| } |
| |
| static int virtio_uclass_child_post_probe(struct udevice *vdev) |
| { |
| /* Indicates that the driver is set up and ready to drive the device */ |
| virtio_add_status(vdev, VIRTIO_CONFIG_S_DRIVER_OK); |
| |
| return 0; |
| } |
| |
| UCLASS_DRIVER(virtio) = { |
| .name = "virtio", |
| .id = UCLASS_VIRTIO, |
| .flags = DM_UC_FLAG_SEQ_ALIAS, |
| .pre_probe = virtio_uclass_pre_probe, |
| .post_probe = virtio_uclass_post_probe, |
| .child_post_bind = virtio_uclass_child_post_bind, |
| .child_pre_probe = virtio_uclass_child_pre_probe, |
| .child_post_probe = virtio_uclass_child_post_probe, |
| .per_device_auto = sizeof(struct virtio_dev_priv), |
| }; |