This adds a new virtio uclass driver for “virtio” [1] family of devices that are are found in virtual environments like QEMU, yet by design they look like physical devices to the guest.
The uclass driver provides child_pre_probe() and child_post_probe() methods to do some common operations for virtio device drivers like device and driver supported feature negotiation, etc.
[1] http://docs.oasis-open.org/virtio/virtio/v1.0/virtio-v1.0.pdf
Signed-off-by: Tuomas Tynkkynen tuomas.tynkkynen@iki.fi Signed-off-by: Bin Meng bmeng.cn@gmail.com
---
Changes in v3: None Changes in v2: - Added virtio spec link and a short statement of what virtio is in the header and source files - Changed to use 'transport' over 'bus' in drivers/virtio/Kconfig - Added UCLASS_VIRTIO ID in alphabetical order - Moved the header file inclusion from virtio.h to C file - Fixed code styling issue (blank line before return) in virtio_xxx() APIs - Changed virtio_init() to return int if there is an error - Added virtio_uclass_pre_probe() to check virtio transport driver ops here so that we don't need check these ops each time when the virtio_xxx APIs are called - Implemented child_post_remove() method to reset the virtio device - Changed virtio_driver_features_init() parameter 'feature' and 'feature_legacy' to const, and adjust member of 'struct virtio_dev_priv' accordingly - Initialize uc_priv->vqs in virtio_uclass_post_probe()
drivers/Kconfig | 2 + drivers/Makefile | 1 + drivers/virtio/Kconfig | 25 ++ drivers/virtio/Makefile | 6 + drivers/virtio/virtio-uclass.c | 369 +++++++++++++++++++++ include/dm/uclass-id.h | 1 + include/virtio.h | 707 +++++++++++++++++++++++++++++++++++++++++ include/virtio_types.h | 24 ++ 8 files changed, 1135 insertions(+) create mode 100644 drivers/virtio/Kconfig create mode 100644 drivers/virtio/Makefile create mode 100644 drivers/virtio/virtio-uclass.c create mode 100644 include/virtio.h create mode 100644 include/virtio_types.h
diff --git a/drivers/Kconfig b/drivers/Kconfig index 927a2b8..4ac823d 100644 --- a/drivers/Kconfig +++ b/drivers/Kconfig @@ -112,6 +112,8 @@ source "drivers/usb/Kconfig"
source "drivers/video/Kconfig"
+source "drivers/virtio/Kconfig" + source "drivers/w1/Kconfig"
source "drivers/w1-eeprom/Kconfig" diff --git a/drivers/Makefile b/drivers/Makefile index fb38b67..4453c62 100644 --- a/drivers/Makefile +++ b/drivers/Makefile @@ -14,6 +14,7 @@ obj-$(CONFIG_$(SPL_TPL_)SERIAL_SUPPORT) += serial/ obj-$(CONFIG_$(SPL_TPL_)SPI_FLASH_SUPPORT) += mtd/spi/ obj-$(CONFIG_$(SPL_TPL_)SPI_SUPPORT) += spi/ obj-$(CONFIG_$(SPL_TPL_)TIMER) += timer/ +obj-$(CONFIG_$(SPL_TPL_)VIRTIO) += virtio/ obj-$(CONFIG_$(SPL_)DM_MAILBOX) += mailbox/ obj-$(CONFIG_$(SPL_)REMOTEPROC) += remoteproc/
diff --git a/drivers/virtio/Kconfig b/drivers/virtio/Kconfig new file mode 100644 index 0000000..82fc536 --- /dev/null +++ b/drivers/virtio/Kconfig @@ -0,0 +1,25 @@ +# 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. + +menu "VirtIO Drivers" + +config VIRTIO + bool + help + This option is selected by any driver which implements the virtio + transport, such as CONFIG_VIRTIO_MMIO or CONFIG_VIRTIO_PCI. + +endmenu diff --git a/drivers/virtio/Makefile b/drivers/virtio/Makefile new file mode 100644 index 0000000..23e7be7 --- /dev/null +++ b/drivers/virtio/Makefile @@ -0,0 +1,6 @@ +# SPDX-License-Identifier: GPL-2.0+ +# +# Copyright (C) 2018, Tuomas Tynkkynen tuomas.tynkkynen@iki.fi +# Copyright (C) 2018, Bin Meng bmeng.cn@gmail.com + +obj-y += virtio-uclass.o diff --git a/drivers/virtio/virtio-uclass.c b/drivers/virtio/virtio-uclass.c new file mode 100644 index 0000000..34397d7 --- /dev/null +++ b/drivers/virtio/virtio-uclass.c @@ -0,0 +1,369 @@ +// 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. + */ + +#include <common.h> +#include <dm.h> +#include <virtio_types.h> +#include <virtio.h> +#include <dm/lists.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, +}; + +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) +{ + struct udevice *bus; + int ret; + + /* Enumerate all known virtio devices */ + ret = uclass_first_device(UCLASS_VIRTIO, &bus); + if (ret) + return ret; + + while (bus) { + ret = uclass_next_device(&bus); + if (ret) + break; + } + + return ret; +} + +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], udev->seq); + 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_alloc_size = sizeof(struct virtio_dev_priv), +}; diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h index 269a2c6..c91dca1 100644 --- a/include/dm/uclass-id.h +++ b/include/dm/uclass-id.h @@ -96,6 +96,7 @@ enum uclass_id { UCLASS_VIDEO_BRIDGE, /* Video bridge, e.g. DisplayPort to LVDS */ UCLASS_VIDEO_CONSOLE, /* Text console driver for video device */ UCLASS_VIDEO_OSD, /* On-screen display */ + UCLASS_VIRTIO, /* VirtIO transport device */ UCLASS_W1, /* Dallas 1-Wire bus */ UCLASS_W1_EEPROM, /* one-wire EEPROMs */ UCLASS_WDT, /* Watchdot Timer driver */ diff --git a/include/virtio.h b/include/virtio.h new file mode 100644 index 0000000..654fdf1 --- /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__ */ diff --git a/include/virtio_types.h b/include/virtio_types.h new file mode 100644 index 0000000..d700d19 --- /dev/null +++ b/include/virtio_types.h @@ -0,0 +1,24 @@ +/* SPDX-License-Identifier: BSD-3-Clause */ +/* + * Copyright (C) 2018, Tuomas Tynkkynen tuomas.tynkkynen@iki.fi + * Copyright (C) 2018, Bin Meng bmeng.cn@gmail.com + * + * From Linux kernel include/uapi/linux/virtio_types.h + */ + +#ifndef _LINUX_VIRTIO_TYPES_H +#define _LINUX_VIRTIO_TYPES_H + +#include <linux/types.h> + +/* + * __virtio{16,32,64} have the following meaning: + * - __u{16,32,64} for virtio devices in legacy mode, accessed in native endian + * - __le{16,32,64} for standard-compliant virtio devices + */ + +typedef __u16 __bitwise __virtio16; +typedef __u32 __bitwise __virtio32; +typedef __u64 __bitwise __virtio64; + +#endif /* _LINUX_VIRTIO_TYPES_H */