jcs.org
qemu with hax to log dma reads & writes
jcs.org/2018/11/12/vfio
1/*
2 * CAN common CAN bus emulation support
3 *
4 * Copyright (c) 2013-2014 Jin Yang
5 * Copyright (c) 2014-2018 Pavel Pisa
6 *
7 * Initial development supported by Google GSoC 2013 from RTEMS project slot
8 *
9 * Permission is hereby granted, free of charge, to any person obtaining a copy
10 * of this software and associated documentation files (the "Software"), to deal
11 * in the Software without restriction, including without limitation the rights
12 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
13 * copies of the Software, and to permit persons to whom the Software is
14 * furnished to do so, subject to the following conditions:
15 *
16 * The above copyright notice and this permission notice shall be included in
17 * all copies or substantial portions of the Software.
18 *
19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
22 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
23 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
24 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
25 * THE SOFTWARE.
26 */
27
28#ifndef NET_CAN_EMU_H
29#define NET_CAN_EMU_H
30
31#include "qemu/queue.h"
32#include "qom/object.h"
33
34/* NOTE: the following two structures is copied from <linux/can.h>. */
35
36/*
37 * Controller Area Network Identifier structure
38 *
39 * bit 0-28 : CAN identifier (11/29 bit)
40 * bit 29 : error frame flag (0 = data frame, 1 = error frame)
41 * bit 30 : remote transmission request flag (1 = rtr frame)
42 * bit 31 : frame format flag (0 = standard 11 bit, 1 = extended 29 bit)
43 */
44typedef uint32_t qemu_canid_t;
45
46typedef struct qemu_can_frame {
47 qemu_canid_t can_id; /* 32 bit CAN_ID + EFF/RTR/ERR flags */
48 uint8_t can_dlc; /* data length code: 0 .. 8 */
49 uint8_t data[8] QEMU_ALIGNED(8);
50} qemu_can_frame;
51
52/* Keep defines for QEMU separate from Linux ones for now */
53
54#define QEMU_CAN_EFF_FLAG 0x80000000U /* EFF/SFF is set in the MSB */
55#define QEMU_CAN_RTR_FLAG 0x40000000U /* remote transmission request */
56#define QEMU_CAN_ERR_FLAG 0x20000000U /* error message frame */
57
58#define QEMU_CAN_SFF_MASK 0x000007FFU /* standard frame format (SFF) */
59#define QEMU_CAN_EFF_MASK 0x1FFFFFFFU /* extended frame format (EFF) */
60
61/**
62 * struct qemu_can_filter - CAN ID based filter in can_register().
63 * @can_id: relevant bits of CAN ID which are not masked out.
64 * @can_mask: CAN mask (see description)
65 *
66 * Description:
67 * A filter matches, when
68 *
69 * <received_can_id> & mask == can_id & mask
70 *
71 * The filter can be inverted (QEMU_CAN_INV_FILTER bit set in can_id) or it can
72 * filter for error message frames (QEMU_CAN_ERR_FLAG bit set in mask).
73 */
74typedef struct qemu_can_filter {
75 qemu_canid_t can_id;
76 qemu_canid_t can_mask;
77} qemu_can_filter;
78
79/* QEMU_CAN_INV_FILTER can be set in qemu_can_filter.can_id */
80#define QEMU_CAN_INV_FILTER 0x20000000U
81
82typedef struct CanBusClientState CanBusClientState;
83typedef struct CanBusState CanBusState;
84
85typedef struct CanBusClientInfo {
86 bool (*can_receive)(CanBusClientState *);
87 ssize_t (*receive)(CanBusClientState *,
88 const struct qemu_can_frame *frames, size_t frames_cnt);
89} CanBusClientInfo;
90
91struct CanBusClientState {
92 CanBusClientInfo *info;
93 CanBusState *bus;
94 int link_down;
95 QTAILQ_ENTRY(CanBusClientState) next;
96 CanBusClientState *peer;
97 char *model;
98 char *name;
99 void (*destructor)(CanBusClientState *);
100};
101
102#define TYPE_CAN_BUS "can-bus"
103#define CAN_BUS_CLASS(klass) \
104 OBJECT_CLASS_CHECK(CanBusClass, (klass), TYPE_CAN_BUS)
105#define CAN_BUS_GET_CLASS(obj) \
106 OBJECT_GET_CLASS(CanBusClass, (obj), TYPE_CAN_BUS)
107#define CAN_BUS(obj) \
108 OBJECT_CHECK(CanBusState, (obj), TYPE_CAN_BUS)
109
110int can_bus_filter_match(struct qemu_can_filter *filter, qemu_canid_t can_id);
111
112int can_bus_insert_client(CanBusState *bus, CanBusClientState *client);
113
114int can_bus_remove_client(CanBusClientState *client);
115
116ssize_t can_bus_client_send(CanBusClientState *,
117 const struct qemu_can_frame *frames,
118 size_t frames_cnt);
119
120int can_bus_client_set_filters(CanBusClientState *,
121 const struct qemu_can_filter *filters,
122 size_t filters_cnt);
123
124#endif