/* 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. * * This file is largely based on Linux kernel virtio_*.h files */ #ifndef __VIRTIO_H__ #define __VIRTIO_H__ #define VIRTIO_ID_NET 1 /* virtio net */ #define VIRTIO_ID_BLOCK 2 /* virtio block */ #define VIRTIO_ID_MAX_NUM 3 #define VIRTIO_NET_DRV_NAME "virtio-net" #define VIRTIO_BLK_DRV_NAME "virtio-blk" /* Status byte for guest to report progress, and synchronize features */ /* We have seen device and processed generic fields (VIRTIO_CONFIG_F_VIRTIO) */ #define VIRTIO_CONFIG_S_ACKNOWLEDGE 1 /* We have found a driver for the device */ #define VIRTIO_CONFIG_S_DRIVER 2 /* Driver has used its parts of the config, and is happy */ #define VIRTIO_CONFIG_S_DRIVER_OK 4 /* Driver has finished configuring features */ #define VIRTIO_CONFIG_S_FEATURES_OK 8 /* Device entered invalid state, driver must reset it */ #define VIRTIO_CONFIG_S_NEEDS_RESET 0x40 /* We've given up on this device */ #define VIRTIO_CONFIG_S_FAILED 0x80 /* * Virtio feature bits VIRTIO_TRANSPORT_F_START through VIRTIO_TRANSPORT_F_END * are reserved for the transport being used (eg: virtio_ring, virtio_pci etc.), * the rest are per-device feature bits. */ #define VIRTIO_TRANSPORT_F_START 28 #define VIRTIO_TRANSPORT_F_END 38 #ifndef VIRTIO_CONFIG_NO_LEGACY /* * Do we get callbacks when the ring is completely used, * even if we've suppressed them? */ #define VIRTIO_F_NOTIFY_ON_EMPTY 24 /* Can the device handle any descriptor layout? */ #define VIRTIO_F_ANY_LAYOUT 27 #endif /* VIRTIO_CONFIG_NO_LEGACY */ /* v1.0 compliant */ #define VIRTIO_F_VERSION_1 32 /* * If clear - device has the IOMMU bypass quirk feature. * If set - use platform tools to detect the IOMMU. * * Note the reverse polarity (compared to most other features), * this is for compatibility with legacy systems. */ #define VIRTIO_F_IOMMU_PLATFORM 33 /* Does the device support Single Root I/O Virtualization? */ #define VIRTIO_F_SR_IOV 37 /** * virtio scatter-gather struct * * @addr: sg buffer address * @lengh: sg buffer length */ struct virtio_sg { void *addr; size_t length; }; struct virtqueue; /* virtio bus operations */ struct dm_virtio_ops { /** * get_config() - read the value of a configuration field * * @vdev: the real virtio device * @offset: the offset of the configuration field * @buf: the buffer to write the field value into * @len: the length of the buffer * @return 0 if OK, -ve on error */ int (*get_config)(struct udevice *vdev, unsigned int offset, void *buf, unsigned int len); /** * set_config() - write the value of a configuration field * * @vdev: the real virtio device * @offset: the offset of the configuration field * @buf: the buffer to read the field value from * @len: the length of the buffer * @return 0 if OK, -ve on error */ int (*set_config)(struct udevice *vdev, unsigned int offset, const void *buf, unsigned int len); /** * generation() - config generation counter * * @vdev: the real virtio device * @counter: the returned config generation counter * @return 0 if OK, -ve on error */ int (*generation)(struct udevice *vdev, u32 *counter); /** * get_status() - read the status byte * * @vdev: the real virtio device * @status: the returned status byte * @return 0 if OK, -ve on error */ int (*get_status)(struct udevice *vdev, u8 *status); /** * set_status() - write the status byte * * @vdev: the real virtio device * @status: the new status byte * @return 0 if OK, -ve on error */ int (*set_status)(struct udevice *vdev, u8 status); /** * reset() - reset the device * * @vdev: the real virtio device * @return 0 if OK, -ve on error */ int (*reset)(struct udevice *vdev); /** * get_features() - get the array of feature bits for this device * * @vdev: the real virtio device * @features: the first 32 feature bits (all we currently need) * @return 0 if OK, -ve on error */ int (*get_features)(struct udevice *vdev, u64 *features); /** * set_features() - confirm what device features we'll be using * * @vdev: the real virtio device * @return 0 if OK, -ve on error */ int (*set_features)(struct udevice *vdev); /** * find_vqs() - find virtqueues and instantiate them * * @vdev: the real virtio device * @nvqs: the number of virtqueues to find * @vqs: on success, includes new virtqueues * @return 0 if OK, -ve on error */ int (*find_vqs)(struct udevice *vdev, unsigned int nvqs, struct virtqueue *vqs[]); /** * del_vqs() - free virtqueues found by find_vqs() * * @vdev: the real virtio device * @return 0 if OK, -ve on error */ int (*del_vqs)(struct udevice *vdev); /** * notify() - notify the device to process the queue * * @vdev: the real virtio device * @vq: virtqueue to process * @return 0 if OK, -ve on error */ int (*notify)(struct udevice *vdev, struct virtqueue *vq); }; /* Get access to a virtio bus' operations */ #define virtio_get_ops(dev) ((struct dm_virtio_ops *)(dev)->driver->ops) /** * virtio uclass per device private data * * @vqs: virtualqueue for the virtio device * @vdev: the real virtio device underneath * @legacy: is it a legacy device? * @device: virtio device ID * @vendor: virtio vendor ID * @features: negotiated supported features * @feature_table: an array of feature supported by the driver * @feature_table_size: number of entries in the feature table array * @feature_table_legacy: same as feature_table but working in legacy mode * @feature_table_size_legacy: number of entries in feature table legacy array */ struct virtio_dev_priv { struct list_head vqs; struct udevice *vdev; bool legacy; u32 device; u32 vendor; u64 features; const u32 *feature_table; u32 feature_table_size; const u32 *feature_table_legacy; u32 feature_table_size_legacy; }; /** * virtio_get_config() - read the value of a configuration field * * @vdev: the real virtio device * @offset: the offset of the configuration field * @buf: the buffer to write the field value into * @len: the length of the buffer * @return 0 if OK, -ve on error */ int virtio_get_config(struct udevice *vdev, unsigned int offset, void *buf, unsigned int len); /** * virtio_set_config() - write the value of a configuration field * * @vdev: the real virtio device * @offset: the offset of the configuration field * @buf: the buffer to read the field value from * @len: the length of the buffer * @return 0 if OK, -ve on error */ int virtio_set_config(struct udevice *vdev, unsigned int offset, void *buf, unsigned int len); /** * virtio_generation() - config generation counter * * @vdev: the real virtio device * @counter: the returned config generation counter * @return 0 if OK, -ve on error */ int virtio_generation(struct udevice *vdev, u32 *counter); /** * virtio_get_status() - read the status byte * * @vdev: the real virtio device * @status: the returned status byte * @return 0 if OK, -ve on error */ int virtio_get_status(struct udevice *vdev, u8 *status); /** * virtio_set_status() - write the status byte * * @vdev: the real virtio device * @status: the new status byte * @return 0 if OK, -ve on error */ int virtio_set_status(struct udevice *vdev, u8 status); /** * virtio_reset() - reset the device * * @vdev: the real virtio device * @return 0 if OK, -ve on error */ int virtio_reset(struct udevice *vdev); /** * virtio_get_features() - get the array of feature bits for this device * * @vdev: the real virtio device * @features: the first 32 feature bits (all we currently need) * @return 0 if OK, -ve on error */ int virtio_get_features(struct udevice *vdev, u64 *features); /** * virtio_set_features() - confirm what device features we'll be using * * @vdev: the real virtio device * @return 0 if OK, -ve on error */ int virtio_set_features(struct udevice *vdev); /** * virtio_find_vqs() - find virtqueues and instantiate them * * @vdev: the real virtio device * @nvqs: the number of virtqueues to find * @vqs: on success, includes new virtqueues * @return 0 if OK, -ve on error */ int virtio_find_vqs(struct udevice *vdev, unsigned int nvqs, struct virtqueue *vqs[]); /** * virtio_del_vqs() - free virtqueues found by find_vqs() * * @vdev: the real virtio device * @return 0 if OK, -ve on error */ int virtio_del_vqs(struct udevice *vdev); /** * virtio_notify() - notify the device to process the queue * * @vdev: the real virtio device * @vq: virtqueue to process * @return 0 if OK, -ve on error */ int virtio_notify(struct udevice *vdev, struct virtqueue *vq); /** * virtio_add_status() - helper to set a new status code to the device * * @vdev: the real virtio device * @status: new status code to be added */ void virtio_add_status(struct udevice *vdev, u8 status); /** * virtio_finalize_features() - helper to finalize features * * @vdev: the real virtio device * @return 0 if OK, -ve on error */ int virtio_finalize_features(struct udevice *vdev); /** * virtio_driver_features_init() - initialize driver supported features * * This fills in the virtio device parent per child private data with the given * information, which contains driver supported features and legacy features. * * This API should be called in the virtio device driver's bind method, so that * later virtio transport uclass driver can utilize the driver supplied features * to negotiate with the device on the final supported features. * * @priv: virtio uclass per device private data * @feature: an array of feature supported by the driver * @feature_size: number of entries in the feature table array * @feature_legacy: same as feature_table but working in legacy mode * @feature_legacy_size:number of entries in feature table legacy array */ void virtio_driver_features_init(struct virtio_dev_priv *priv, const u32 *feature, u32 feature_size, const u32 *feature_legacy, u32 feature_legacy_size); /** * virtio_init() - helper to enumerate all known virtio devices * * @return 0 if OK, -ve on error */ int virtio_init(void); static inline u16 __virtio16_to_cpu(bool little_endian, __virtio16 val) { if (little_endian) return le16_to_cpu((__force __le16)val); else return be16_to_cpu((__force __be16)val); } static inline __virtio16 __cpu_to_virtio16(bool little_endian, u16 val) { if (little_endian) return (__force __virtio16)cpu_to_le16(val); else return (__force __virtio16)cpu_to_be16(val); } static inline u32 __virtio32_to_cpu(bool little_endian, __virtio32 val) { if (little_endian) return le32_to_cpu((__force __le32)val); else return be32_to_cpu((__force __be32)val); } static inline __virtio32 __cpu_to_virtio32(bool little_endian, u32 val) { if (little_endian) return (__force __virtio32)cpu_to_le32(val); else return (__force __virtio32)cpu_to_be32(val); } static inline u64 __virtio64_to_cpu(bool little_endian, __virtio64 val) { if (little_endian) return le64_to_cpu((__force __le64)val); else return be64_to_cpu((__force __be64)val); } static inline __virtio64 __cpu_to_virtio64(bool little_endian, u64 val) { if (little_endian) return (__force __virtio64)cpu_to_le64(val); else return (__force __virtio64)cpu_to_be64(val); } /** * __virtio_test_bit - helper to test feature bits * * For use by transports. Devices should normally use virtio_has_feature, * which includes more checks. * * @udev: the transport device * @fbit: the feature bit */ static inline bool __virtio_test_bit(struct udevice *udev, unsigned int fbit) { struct virtio_dev_priv *uc_priv = dev_get_uclass_priv(udev); /* Did you forget to fix assumptions on max features? */ if (__builtin_constant_p(fbit)) BUILD_BUG_ON(fbit >= 64); else WARN_ON(fbit >= 64); return uc_priv->features & BIT_ULL(fbit); } /** * __virtio_set_bit - helper to set feature bits * * For use by transports. * * @udev: the transport device * @fbit: the feature bit */ static inline void __virtio_set_bit(struct udevice *udev, unsigned int fbit) { struct virtio_dev_priv *uc_priv = dev_get_uclass_priv(udev); /* Did you forget to fix assumptions on max features? */ if (__builtin_constant_p(fbit)) BUILD_BUG_ON(fbit >= 64); else WARN_ON(fbit >= 64); uc_priv->features |= BIT_ULL(fbit); } /** * __virtio_clear_bit - helper to clear feature bits * * For use by transports. * * @vdev: the transport device * @fbit: the feature bit */ static inline void __virtio_clear_bit(struct udevice *udev, unsigned int fbit) { struct virtio_dev_priv *uc_priv = dev_get_uclass_priv(udev); /* Did you forget to fix assumptions on max features? */ if (__builtin_constant_p(fbit)) BUILD_BUG_ON(fbit >= 64); else WARN_ON(fbit >= 64); uc_priv->features &= ~BIT_ULL(fbit); } /** * virtio_has_feature - helper to determine if this device has this feature * * Note this API is only usable after the virtio device driver's bind phase, * as the feature has been negotiated between the device and the driver. * * @vdev: the virtio device * @fbit: the feature bit */ static inline bool virtio_has_feature(struct udevice *vdev, unsigned int fbit) { if (!(vdev->flags & DM_FLAG_BOUND)) WARN_ON(true); return __virtio_test_bit(vdev->parent, fbit); } static inline bool virtio_legacy_is_little_endian(void) { #ifdef __LITTLE_ENDIAN return true; #else return false; #endif } static inline bool virtio_is_little_endian(struct udevice *vdev) { struct virtio_dev_priv *uc_priv = dev_get_uclass_priv(vdev->parent); return !uc_priv->legacy || virtio_legacy_is_little_endian(); } /* Memory accessors */ static inline u16 virtio16_to_cpu(struct udevice *vdev, __virtio16 val) { return __virtio16_to_cpu(virtio_is_little_endian(vdev), val); } static inline __virtio16 cpu_to_virtio16(struct udevice *vdev, u16 val) { return __cpu_to_virtio16(virtio_is_little_endian(vdev), val); } static inline u32 virtio32_to_cpu(struct udevice *vdev, __virtio32 val) { return __virtio32_to_cpu(virtio_is_little_endian(vdev), val); } static inline __virtio32 cpu_to_virtio32(struct udevice *vdev, u32 val) { return __cpu_to_virtio32(virtio_is_little_endian(vdev), val); } static inline u64 virtio64_to_cpu(struct udevice *vdev, __virtio64 val) { return __virtio64_to_cpu(virtio_is_little_endian(vdev), val); } static inline __virtio64 cpu_to_virtio64(struct udevice *vdev, u64 val) { return __cpu_to_virtio64(virtio_is_little_endian(vdev), val); } /* Read @count fields, @bytes each */ static inline void __virtio_cread_many(struct udevice *vdev, unsigned int offset, void *buf, size_t count, size_t bytes) { u32 old, gen; int i; /* no need to check return value as generation can be optional */ virtio_generation(vdev, &gen); do { old = gen; for (i = 0; i < count; i++) virtio_get_config(vdev, offset + bytes * i, buf + i * bytes, bytes); virtio_generation(vdev, &gen); } while (gen != old); } static inline void virtio_cread_bytes(struct udevice *vdev, unsigned int offset, void *buf, size_t len) { __virtio_cread_many(vdev, offset, buf, len, 1); } static inline u8 virtio_cread8(struct udevice *vdev, unsigned int offset) { u8 ret; virtio_get_config(vdev, offset, &ret, sizeof(ret)); return ret; } static inline void virtio_cwrite8(struct udevice *vdev, unsigned int offset, u8 val) { virtio_set_config(vdev, offset, &val, sizeof(val)); } static inline u16 virtio_cread16(struct udevice *vdev, unsigned int offset) { u16 ret; virtio_get_config(vdev, offset, &ret, sizeof(ret)); return virtio16_to_cpu(vdev, (__force __virtio16)ret); } static inline void virtio_cwrite16(struct udevice *vdev, unsigned int offset, u16 val) { val = (__force u16)cpu_to_virtio16(vdev, val); virtio_set_config(vdev, offset, &val, sizeof(val)); } static inline u32 virtio_cread32(struct udevice *vdev, unsigned int offset) { u32 ret; virtio_get_config(vdev, offset, &ret, sizeof(ret)); return virtio32_to_cpu(vdev, (__force __virtio32)ret); } static inline void virtio_cwrite32(struct udevice *vdev, unsigned int offset, u32 val) { val = (__force u32)cpu_to_virtio32(vdev, val); virtio_set_config(vdev, offset, &val, sizeof(val)); } static inline u64 virtio_cread64(struct udevice *vdev, unsigned int offset) { u64 ret; __virtio_cread_many(vdev, offset, &ret, 1, sizeof(ret)); return virtio64_to_cpu(vdev, (__force __virtio64)ret); } static inline void virtio_cwrite64(struct udevice *vdev, unsigned int offset, u64 val) { val = (__force u64)cpu_to_virtio64(vdev, val); virtio_set_config(vdev, offset, &val, sizeof(val)); } /* Config space read accessor */ #define virtio_cread(vdev, structname, member, ptr) \ do { \ /* Must match the member's type, and be integer */ \ if (!typecheck(typeof((((structname *)0)->member)), *(ptr))) \ (*ptr) = 1; \ \ switch (sizeof(*ptr)) { \ case 1: \ *(ptr) = virtio_cread8(vdev, \ offsetof(structname, member)); \ break; \ case 2: \ *(ptr) = virtio_cread16(vdev, \ offsetof(structname, member)); \ break; \ case 4: \ *(ptr) = virtio_cread32(vdev, \ offsetof(structname, member)); \ break; \ case 8: \ *(ptr) = virtio_cread64(vdev, \ offsetof(structname, member)); \ break; \ default: \ WARN_ON(true); \ } \ } while (0) /* Config space write accessor */ #define virtio_cwrite(vdev, structname, member, ptr) \ do { \ /* Must match the member's type, and be integer */ \ if (!typecheck(typeof((((structname *)0)->member)), *(ptr))) \ WARN_ON((*ptr) == 1); \ \ switch (sizeof(*ptr)) { \ case 1: \ virtio_cwrite8(vdev, \ offsetof(structname, member), \ *(ptr)); \ break; \ case 2: \ virtio_cwrite16(vdev, \ offsetof(structname, member), \ *(ptr)); \ break; \ case 4: \ virtio_cwrite32(vdev, \ offsetof(structname, member), \ *(ptr)); \ break; \ case 8: \ virtio_cwrite64(vdev, \ offsetof(structname, member), \ *(ptr)); \ break; \ default: \ WARN_ON(true); \ } \ } while (0) /* Conditional config space accessors */ #define virtio_cread_feature(vdev, fbit, structname, member, ptr) \ ({ \ int _r = 0; \ if (!virtio_has_feature(vdev, fbit)) \ _r = -ENOENT; \ else \ virtio_cread(vdev, structname, member, ptr); \ _r; \ }) #endif /* __VIRTIO_H__ */