1 files changed, 707 insertions, 0 deletions

diff --git a/include/virtio.h b/include/virtio.h
new file mode 100644
index 0000000000..654fdf154b
--- /dev/null
+++ b/include/virtio.h
@@ -0,0 +1,707 @@
+/* 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__ */