xref: /qemu/hw/display/framebuffer.c (revision abff1abf)
1 /*
2  * Framebuffer device helper routines
3  *
4  * Copyright (c) 2009 CodeSourcery
5  * Written by Paul Brook <paul@codesourcery.com>
6  *
7  * This code is licensed under the GNU GPLv2.
8  *
9  * Contributions after 2012-01-13 are licensed under the terms of the
10  * GNU GPL, version 2 or (at your option) any later version.
11  */
12 
13 /* TODO:
14    - Do something similar for framebuffers with local ram
15    - Handle rotation here instead of hacking dest_pitch
16    - Use common pixel conversion routines instead of per-device drawfn
17    - Remove all DisplayState knowledge from devices.
18  */
19 
20 #include "qemu/osdep.h"
21 #include "ui/console.h"
22 #include "framebuffer.h"
23 
24 void framebuffer_update_memory_section(
25     MemoryRegionSection *mem_section,
26     MemoryRegion *root,
27     hwaddr base,
28     unsigned rows,
29     unsigned src_width)
30 {
31     hwaddr src_len = (hwaddr)rows * src_width;
32 
33     if (mem_section->mr) {
34         memory_region_set_log(mem_section->mr, false, DIRTY_MEMORY_VGA);
35         memory_region_unref(mem_section->mr);
36         mem_section->mr = NULL;
37     }
38 
39     *mem_section = memory_region_find(root, base, src_len);
40     if (!mem_section->mr) {
41         return;
42     }
43 
44     if (int128_get64(mem_section->size) < src_len ||
45             !memory_region_is_ram(mem_section->mr)) {
46         memory_region_unref(mem_section->mr);
47         mem_section->mr = NULL;
48         return;
49     }
50 
51     memory_region_set_log(mem_section->mr, true, DIRTY_MEMORY_VGA);
52 }
53 
54 /* Render an image from a shared memory framebuffer.  */
55 void framebuffer_update_display(
56     DisplaySurface *ds,
57     MemoryRegionSection *mem_section,
58     int cols, /* Width in pixels.  */
59     int rows, /* Height in pixels.  */
60     int src_width, /* Length of source line, in bytes.  */
61     int dest_row_pitch, /* Bytes between adjacent horizontal output pixels.  */
62     int dest_col_pitch, /* Bytes between adjacent vertical output pixels.  */
63     int invalidate, /* nonzero to redraw the whole image.  */
64     drawfn fn,
65     void *opaque,
66     int *first_row, /* Input and output.  */
67     int *last_row /* Output only */)
68 {
69     DirtyBitmapSnapshot *snap;
70     uint8_t *dest;
71     uint8_t *src;
72     int first, last = 0;
73     int dirty;
74     int i;
75     ram_addr_t addr;
76     MemoryRegion *mem;
77 
78     i = *first_row;
79     *first_row = -1;
80 
81     mem = mem_section->mr;
82     if (!mem) {
83         return;
84     }
85 
86     addr = mem_section->offset_within_region;
87     src = memory_region_get_ram_ptr(mem) + addr;
88 
89     dest = surface_data(ds);
90     if (dest_col_pitch < 0) {
91         dest -= dest_col_pitch * (cols - 1);
92     }
93     if (dest_row_pitch < 0) {
94         dest -= dest_row_pitch * (rows - 1);
95     }
96     first = -1;
97 
98     addr += i * src_width;
99     src += i * src_width;
100     dest += i * dest_row_pitch;
101 
102     snap = memory_region_snapshot_and_clear_dirty(mem, addr, src_width * rows,
103                                                   DIRTY_MEMORY_VGA);
104     for (; i < rows; i++) {
105         dirty = memory_region_snapshot_get_dirty(mem, snap, addr, src_width);
106         if (dirty || invalidate) {
107             fn(opaque, dest, src, cols, dest_col_pitch);
108             if (first == -1)
109                 first = i;
110             last = i;
111         }
112         addr += src_width;
113         src += src_width;
114         dest += dest_row_pitch;
115     }
116     g_free(snap);
117     if (first < 0) {
118         return;
119     }
120     *first_row = first;
121     *last_row = last;
122 }
123