xref: /freebsd/sys/dev/virtio/virtio_config.h (revision 95ee2897e98f5d444f26ed2334cc7c439f9c16c6)

/*-
 * This header is BSD licensed so anyone can use the definitions to implement
 * compatible drivers/servers.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of IBM nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#ifndef _VIRTIO_CONFIG_H_
#define _VIRTIO_CONFIG_H_

/* Status byte for guest to report progress. */
#define VIRTIO_CONFIG_STATUS_RESET	0x00
/* We have seen device and processed generic fields. */
#define VIRTIO_CONFIG_STATUS_ACK	0x01
/* We have found a driver for the device. */
#define VIRTIO_CONFIG_STATUS_DRIVER	0x02
/* Driver has used its parts of the config, and is happy. */
#define VIRTIO_CONFIG_STATUS_DRIVER_OK	0x04
/* Driver has finished configuring features (modern only). */
#define VIRTIO_CONFIG_S_FEATURES_OK	0x08
/* 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_STATUS_FAILED	0x80

/*
 * Generate interrupt when the virtqueue ring is
 * completely used, even if we've suppressed them.
 */
#define VIRTIO_F_NOTIFY_ON_EMPTY	(1UL << 24)

/* Can the device handle any descriptor layout? */
#define VIRTIO_F_ANY_LAYOUT		(1UL << 27)

/* Support for indirect buffer descriptors. */
#define VIRTIO_RING_F_INDIRECT_DESC	(1UL << 28)

/* Support to suppress interrupt until specific index is reached. */
#define VIRTIO_RING_F_EVENT_IDX		(1UL << 29)

/*
 * The guest should never negotiate this feature; it
 * is used to detect faulty drivers.
 */
#define VIRTIO_F_BAD_FEATURE	(1UL << 30)

/* v1.0 compliant. */
#define VIRTIO_F_VERSION_1	(1ULL << 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		(1ULL << 33)

/*
 * Some VirtIO feature bits (currently bits 28 through 34) are
 * reserved for the transport being used (eg. virtio_ring), the
 * rest are per-device feature bits.
 */
#define VIRTIO_TRANSPORT_F_START	28
#define VIRTIO_TRANSPORT_F_END		34

#endif /* _VIRTIO_CONFIG_H_ */