From mboxrd@z Thu Jan 1 00:00:00 1970 From: Simon Glass Date: Thu, 27 Sep 2018 06:42:04 -0700 Subject: [U-Boot] [PATCH 02/27] dm: Add a new uclass driver for VirtIO transport devices In-Reply-To: <1537710145-1888-3-git-send-email-bmeng.cn@gmail.com> References: <1537710145-1888-1-git-send-email-bmeng.cn@gmail.com> <1537710145-1888-3-git-send-email-bmeng.cn@gmail.com> Message-ID: List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit To: u-boot@lists.denx.de Hi Bin, On 23 September 2018 at 06:42, Bin Meng wrote: > 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 Can you add this link to the header file too? This seems to be lacking docs.in the source code. Also in a header file, a short statement of what virtio is for would be good. > > Signed-off-by: Tuomas Tynkkynen > Signed-off-by: Bin Meng > --- > > drivers/Kconfig | 2 + > drivers/Makefile | 1 + > drivers/virtio/Kconfig | 14 + > drivers/virtio/Makefile | 6 + > drivers/virtio/virtio-uclass.c | 333 ++++++++++++++++++++ > include/dm/uclass-id.h | 1 + > include/virtio.h | 694 +++++++++++++++++++++++++++++++++++++++++ > include/virtio_types.h | 24 ++ > 8 files changed, 1075 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 56536c4..d40db0d 100644 > --- a/drivers/Kconfig > +++ b/drivers/Kconfig > @@ -106,6 +106,8 @@ source "drivers/usb/Kconfig" > > source "drivers/video/Kconfig" > > +source "drivers/virtio/Kconfig" > + > source "drivers/watchdog/Kconfig" > > config PHYS_TO_BUS > diff --git a/drivers/Makefile b/drivers/Makefile > index 23ea609..f09daae 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..bdfa96a > --- /dev/null > +++ b/drivers/virtio/Kconfig > @@ -0,0 +1,14 @@ > +# SPDX-License-Identifier: GPL-2.0+ > +# > +# Copyright (C) 2018, Tuomas Tynkkynen > +# Copyright (C) 2018, Bin Meng > + > +menu "VirtIO Drivers" > + > +config VIRTIO > + bool > + help > + This option is selected by any driver which implements the virtio > + bus, such as CONFIG_VIRTIO_MMIO or CONFIG_VIRTIO_PCI. What is a virtio bus? > + > +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 > +# Copyright (C) 2018, Bin Meng > + > +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..1c85856 > --- /dev/null > +++ b/drivers/virtio/virtio-uclass.c > @@ -0,0 +1,333 @@ > +// SPDX-License-Identifier: GPL-2.0+ > +/* > + * Copyright (C) 2018, Tuomas Tynkkynen > + * Copyright (C) 2018, Bin Meng > + */ > + > +#include > +#include > +#include > +#include > +#include > + > +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); > + if (!ops->get_config) > + return -ENOSYS; blank line before return (fix globally) > + 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); > + if (!ops->set_config) > + return -ENOSYS; > + 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); > + if (!ops->get_status) > + return -ENOSYS; > + 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); > + if (!ops->set_status) > + return -ENOSYS; > + return ops->set_status(vdev->parent, status); > +} > + > +int virtio_reset(struct udevice *vdev) > +{ > + struct dm_virtio_ops *ops; > + > + ops = virtio_get_ops(vdev->parent); > + if (!ops->reset) > + return -ENOSYS; > + 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); > + if (!ops->get_features) > + return -ENOSYS; > + 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); > + if (!ops->set_features) > + return -ENOSYS; > + 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); > + if (!ops->find_vqs) > + return -ENOSYS; > + 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); > + if (!ops->del_vqs) > + return -ENOSYS; > + 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); > + if (!ops->notify) > + return -ENOSYS; > + 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, > + u32 *feature, u32 feature_size, > + 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; > +} > + > +void virtio_init(void) Shouldn't this return int if there is an error? > +{ > + struct udevice *bus; > + > + /* Enumerate all known virtio devices */ > + for (uclass_first_device(UCLASS_VIRTIO, &bus); > + bus; > + uclass_next_device(&bus)) { > + ; > + } > +} > + > +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; You might consider using log_ret() or log_msg_ret() for your error returns > + > + 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); > + > + 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); Not sure this is worth having a new hook? > + > + 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, > + .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 7027ea0..08b2a8f 100644 > --- a/include/dm/uclass-id.h > +++ b/include/dm/uclass-id.h > @@ -93,6 +93,7 @@ enum uclass_id { > UCLASS_VIDEO_BRIDGE, /* Video bridge, e.g. DisplayPort to LVDS */ > UCLASS_VIDEO_CONSOLE, /* Text console driver for video device */ > UCLASS_WDT, /* Watchdot Timer driver */ > + UCLASS_VIRTIO, /* VirtIO transport device */ V before W :-) > > UCLASS_COUNT, > UCLASS_INVALID = -1, > diff --git a/include/virtio.h b/include/virtio.h > new file mode 100644 > index 0000000..efbedb2 > --- /dev/null > +++ b/include/virtio.h > @@ -0,0 +1,694 @@ > +/* SPDX-License-Identifier: GPL-2.0+ */ > +/* > + * Copyright (C) 2018, Tuomas Tynkkynen > + * Copyright (C) 2018, Bin Meng > + * > + * This file is largely based on Linux kernel virtio_*.h files > + */ > + > +#ifndef __VIRTIO_H__ > +#define __VIRTIO_H__ > + > +#include > +#include Should be able to avoid this, just put in C file > + > +#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; > + u32 *feature_table; > + u32 feature_table_size; > + 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, > + u32 *feature, u32 feature_size, > + u32 *feature_legacy, u32 feature_legacy_size); > + > +/** > + * virtio_init() - helper to enumerate all known virtio devices > + */ > +void 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); Why is this (and the ones below) inline? I worry this might bloat the code for no purpose? > +} > + > +/** > + * __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; > + > + virtio_generation(vdev, &gen); Error check? Should be in the uclass C file I think > + 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 > + * Copyright (C) 2018, Bin Meng > + * > + * From Linux kernel include/uapi/linux/virtio_types.h > + */ > + > +#ifndef _LINUX_VIRTIO_TYPES_H > +#define _LINUX_VIRTIO_TYPES_H > + > +#include > + > +/* > + * __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 */ > -- > 2.7.4 > Regards, Simon