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Add VirtIO PCI v1.0 attachments and fix the drivers affected.

The vioif, ld, scsi, viornd and viomb devices were adjusted when needed and
tested both in legacy 0.9 and v1.0 attachments trough PCI on amd64, sparc64,
aarch64 and aarch64-eb. ACPI/FDT attachments also tested on
aarch64/aarch64-eb.

Known issues

* viomb on aarch64 works only with ACPI/FDT attachment but not with PCI
  attachment. PCI and ACPI/FDT attachment works on aarch64-eb.

* virtio on sparc64 attaches but is it not functioning though not a
  regression.

/*	$NetBSD: virtioreg.h,v 1.7 2021/01/20 19:46:48 reinoud Exp $	*/

/*
 * Copyright (c) 2010 Minoura Makoto.
 * All rights reserved.
 *
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 THE AUTHOR 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.
 */

/*
 * Part of the file derived from `Virtio PCI Card Specification v0.8.6 DRAFT'
 * Appendix A.
 */
/* An interface for efficient virtio implementation.
 *
 * This header is BSD licensed so anyone can use the definitions
 * to implement compatible drivers/servers.
 *
 * Copyright 2007, 2009, IBM Corporation
 * All rights reserved.
 *
 * 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 _DEV_PCI_VIRTIOREG_H_
#define	_DEV_PCI_VIRTIOREG_H_

#include <sys/types.h>

/* Virtio product id (all subsystems) */
#define VIRTIO_DEVICE_ID_NETWORK	 1
#define VIRTIO_DEVICE_ID_BLOCK		 2
#define VIRTIO_DEVICE_ID_CONSOLE	 3
#define VIRTIO_DEVICE_ID_ENTROPY	 4
#define VIRTIO_DEVICE_ID_BALLOON	 5
#define VIRTIO_DEVICE_ID_IOMEM		 6
#define VIRTIO_DEVICE_ID_RPMSG		 7
#define VIRTIO_DEVICE_ID_SCSI		 8
#define VIRTIO_DEVICE_ID_9P		 9

/* common device/guest features */
#define  VIRTIO_F_NOTIFY_ON_EMPTY		(1<<24)
#define  VIRTIO_F_RING_INDIRECT_DESC		(1<<28)
#define  VIRTIO_F_RING_EVENT_IDX		(1<<29)
#define  VIRTIO_F_BAD_FEATURE			(1<<30)
#define  VIRTIO_F_VERSION_1			(1ULL<<32)

/* common device status flags */
#define  VIRTIO_CONFIG_DEVICE_STATUS_RESET		  0
#define  VIRTIO_CONFIG_DEVICE_STATUS_ACK		  1
#define  VIRTIO_CONFIG_DEVICE_STATUS_DRIVER		  2
#define  VIRTIO_CONFIG_DEVICE_STATUS_DRIVER_OK		  4
#define  VIRTIO_CONFIG_DEVICE_STATUS_FEATURES_OK	  8
#define  VIRTIO_CONFIG_DEVICE_STATUS_DEVICE_NEEDS_RESET	 64
#define  VIRTIO_CONFIG_DEVICE_STATUS_FAILED		128

/* common ISR status flags */
#define  VIRTIO_CONFIG_ISR_QUEUE_INTERRUPT	1
#define  VIRTIO_CONFIG_ISR_CONFIG_CHANGE	2

/* common device/guest features */
#define VIRTIO_COMMON_FLAG_BITS \
        "\20" \
	"\x1f""BAD_FEATURE" \
	"\x1e""EVENT_IDX" \
	"\x1d""INDIRECT_DESC" \
	"\x19""NOTIFY_ON_EMPTY"


/*
 * Virtqueue
 */

/* marks a buffer as continuing via the next field. */
#define VRING_DESC_F_NEXT       1

/* marks a buffer as write-only (otherwise read-only). */
#define VRING_DESC_F_WRITE      2

/* the buffer contains a list of buffer descriptors. */
#define VRING_DESC_F_INDIRECT	4


/*
 * The Host uses this in used->flags to advise the Guest: don't kick me when
 * you add a buffer.  It's unreliable, so it's simply an optimization.  Guest
 * will still kick if it's out of buffers.
 */
#define VRING_USED_F_NO_NOTIFY  1

/*
 * The Guest uses this in avail->flags to advise the Host: don't interrupt me
 * when you consume a buffer.  It's unreliable, so it's simply an
 * optimization.
 */
#define VRING_AVAIL_F_NO_INTERRUPT      1


/* Virtio ring descriptors: 16 bytes.
 * These can chain together via "next". */
struct vring_desc {
        /* Address (guest-physical). */
        uint64_t addr;
        /* Length. */
        uint32_t len;
        /* The flags as indicated above. */
        uint16_t flags;
        /* We chain unused descriptors via this, too */
        uint16_t next;
} __packed;

struct vring_avail {
        uint16_t flags;
        uint16_t idx;
        uint16_t ring[0];
	/* trailed by uint16_t used_event when VIRTIO_F_RING_EVENT_IDX */
} __packed;

/* u32 is used here for ids for padding reasons. */
struct vring_used_elem {
        /* Index of start of used descriptor chain. */
        uint32_t id;
        /* Total length of the descriptor chain which was written to. */
        uint32_t len;
} __packed;

struct vring_used {
        uint16_t flags;
        uint16_t idx;
        struct vring_used_elem ring[0];
	/* trailed by uint16_t avail_event when VIRTIO_F_RING_EVENT_IDX */
} __packed;

/* The standard layout for the ring is a continuous chunk of memory which
 * looks like this.  We assume num is a power of 2.
 *
 * struct vring {
 *      // The actual descriptors (16 bytes each)
 *      struct vring_desc desc[num];
 *
 *      // A ring of available descriptor heads with free-running index.
 *      __u16 avail_flags;
 *      __u16 avail_idx;
 *      __u16 available[num];
 *
 *      // Padding to the next align boundary.
 *      char pad[];
 *
 *      // A ring of used descriptor heads with free-running index.
 *      __u16 used_flags;
 *      __u16 used_idx;
 *      struct vring_used_elem used[num];
 * };
 * Note: for virtio PCI, align is 4096.
 */

#define VIRTIO_PAGE_SIZE	(4096)

#endif /* _DEV_PCI_VIRTIOREG_H_ */