1/*
2 * fbif.h -- Xen virtual frame buffer device
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a copy
5 * of this software and associated documentation files (the "Software"), to
6 * deal in the Software without restriction, including without limitation the
7 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
8 * sell copies of the Software, and to permit persons to whom the Software is
9 * furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice shall be included in
12 * all copies or substantial portions of the Software.
13 *
14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
17 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
18 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
19 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
20 * DEALINGS IN THE SOFTWARE.
21 *
22 * Copyright (C) 2005 Anthony Liguori <aliguori@us.ibm.com>
23 * Copyright (C) 2006 Red Hat, Inc., Markus Armbruster <armbru@redhat.com>
24 */
25
26#ifndef __XEN_PUBLIC_IO_FBIF_H__
27#define __XEN_PUBLIC_IO_FBIF_H__
28
29/* Out events (frontend -> backend) */
30
31/*
32 * Out events may be sent only when requested by backend, and receipt
33 * of an unknown out event is an error.
34 */
35
36/* Event type 1 currently not used */
37/*
38 * Framebuffer update notification event
39 * Capable frontend sets feature-update in xenstore.
40 * Backend requests it by setting request-update in xenstore.
41 */
42#define XENFB_TYPE_UPDATE 2
43
44struct xenfb_update
45{
46    uint8_t type;    /* XENFB_TYPE_UPDATE */
47    int32_t x;      /* source x */
48    int32_t y;      /* source y */
49    int32_t width;  /* rect width */
50    int32_t height; /* rect height */
51};
52
53/*
54 * Framebuffer resize notification event
55 * Capable backend sets feature-resize in xenstore.
56 */
57#define XENFB_TYPE_RESIZE 3
58
59struct xenfb_resize
60{
61    uint8_t type;    /* XENFB_TYPE_RESIZE */
62    int32_t width;   /* width in pixels */
63    int32_t height;  /* height in pixels */
64    int32_t stride;  /* stride in bytes */
65    int32_t depth;   /* depth in bits */
66    int32_t offset;  /* offset of the framebuffer in bytes */
67};
68
69#define XENFB_OUT_EVENT_SIZE 40
70
71union xenfb_out_event
72{
73    uint8_t type;
74    struct xenfb_update update;
75    struct xenfb_resize resize;
76    char pad[XENFB_OUT_EVENT_SIZE];
77};
78
79/* In events (backend -> frontend) */
80
81/*
82 * Frontends should ignore unknown in events.
83 */
84
85/*
86 * Framebuffer refresh period advice
87 * Backend sends it to advise the frontend their preferred period of
88 * refresh.  Frontends that keep the framebuffer constantly up-to-date
89 * just ignore it.  Frontends that use the advice should immediately
90 * refresh the framebuffer (and send an update notification event if
91 * those have been requested), then use the update frequency to guide
92 * their periodical refreshs.
93 */
94#define XENFB_TYPE_REFRESH_PERIOD 1
95#define XENFB_NO_REFRESH 0
96
97struct xenfb_refresh_period
98{
99    uint8_t type;    /* XENFB_TYPE_UPDATE_PERIOD */
100    uint32_t period; /* period of refresh, in ms,
101                      * XENFB_NO_REFRESH if no refresh is needed */
102};
103
104#define XENFB_IN_EVENT_SIZE 40
105
106union xenfb_in_event
107{
108    uint8_t type;
109    struct xenfb_refresh_period refresh_period;
110    char pad[XENFB_IN_EVENT_SIZE];
111};
112
113/* shared page */
114
115#define XENFB_IN_RING_SIZE 1024
116#define XENFB_IN_RING_LEN (XENFB_IN_RING_SIZE / XENFB_IN_EVENT_SIZE)
117#define XENFB_IN_RING_OFFS 1024
118#define XENFB_IN_RING(page) \
119    ((union xenfb_in_event *)((char *)(page) + XENFB_IN_RING_OFFS))
120#define XENFB_IN_RING_REF(page, idx) \
121    (XENFB_IN_RING((page))[(idx) % XENFB_IN_RING_LEN])
122
123#define XENFB_OUT_RING_SIZE 2048
124#define XENFB_OUT_RING_LEN (XENFB_OUT_RING_SIZE / XENFB_OUT_EVENT_SIZE)
125#define XENFB_OUT_RING_OFFS (XENFB_IN_RING_OFFS + XENFB_IN_RING_SIZE)
126#define XENFB_OUT_RING(page) \
127    ((union xenfb_out_event *)((char *)(page) + XENFB_OUT_RING_OFFS))
128#define XENFB_OUT_RING_REF(page, idx) \
129    (XENFB_OUT_RING((page))[(idx) % XENFB_OUT_RING_LEN])
130
131struct xenfb_page
132{
133    uint32_t in_cons, in_prod;
134    uint32_t out_cons, out_prod;
135
136    int32_t width;          /* the width of the framebuffer (in pixels) */
137    int32_t height;         /* the height of the framebuffer (in pixels) */
138    uint32_t line_length;   /* the length of a row of pixels (in bytes) */
139    uint32_t mem_length;    /* the length of the framebuffer (in bytes) */
140    uint8_t depth;          /* the depth of a pixel (in bits) */
141
142    /*
143     * Framebuffer page directory
144     *
145     * Each directory page holds PAGE_SIZE / sizeof(*pd)
146     * framebuffer pages, and can thus map up to PAGE_SIZE *
147     * PAGE_SIZE / sizeof(*pd) bytes.  With PAGE_SIZE == 4096 and
148     * sizeof(unsigned long) == 4/8, that's 4 Megs 32 bit and 2 Megs
149     * 64 bit.  256 directories give enough room for a 512 Meg
150     * framebuffer with a max resolution of 12,800x10,240.  Should
151     * be enough for a while with room leftover for expansion.
152     */
153    unsigned long pd[256];
154};
155
156/*
157 * Wart: xenkbd needs to know default resolution.  Put it here until a
158 * better solution is found, but don't leak it to the backend.
159 */
160#ifdef __KERNEL__
161#define XENFB_WIDTH 800
162#define XENFB_HEIGHT 600
163#define XENFB_DEPTH 32
164#endif
165
166#endif
167
168/*
169 * Local variables:
170 * mode: C
171 * c-file-style: "BSD"
172 * c-basic-offset: 4
173 * tab-width: 4
174 * indent-tabs-mode: nil
175 * End:
176 */
177