xref: /openbmc/qemu/hw/display/framebuffer.c (revision dc5bd18f)
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 "hw/hw.h"
22 #include "ui/console.h"
23 #include "framebuffer.h"
24 
25 void framebuffer_update_memory_section(
26     MemoryRegionSection *mem_section,
27     MemoryRegion *root,
28     hwaddr base,
29     unsigned rows,
30     unsigned src_width)
31 {
32     hwaddr src_len = (hwaddr)rows * src_width;
33 
34     if (mem_section->mr) {
35         memory_region_set_log(mem_section->mr, false, DIRTY_MEMORY_VGA);
36         memory_region_unref(mem_section->mr);
37         mem_section->mr = NULL;
38     }
39 
40     *mem_section = memory_region_find(root, base, src_len);
41     if (!mem_section->mr) {
42         return;
43     }
44 
45     if (int128_get64(mem_section->size) < src_len ||
46             !memory_region_is_ram(mem_section->mr)) {
47         memory_region_unref(mem_section->mr);
48         mem_section->mr = NULL;
49         return;
50     }
51 
52     memory_region_set_log(mem_section->mr, true, DIRTY_MEMORY_VGA);
53 }
54 
55 /* Render an image from a shared memory framebuffer.  */
56 void framebuffer_update_display(
57     DisplaySurface *ds,
58     MemoryRegionSection *mem_section,
59     int cols, /* Width in pixels.  */
60     int rows, /* Height in pixels.  */
61     int src_width, /* Length of source line, in bytes.  */
62     int dest_row_pitch, /* Bytes between adjacent horizontal output pixels.  */
63     int dest_col_pitch, /* Bytes between adjacent vertical output pixels.  */
64     int invalidate, /* nonzero to redraw the whole image.  */
65     drawfn fn,
66     void *opaque,
67     int *first_row, /* Input and output.  */
68     int *last_row /* Output only */)
69 {
70     DirtyBitmapSnapshot *snap;
71     uint8_t *dest;
72     uint8_t *src;
73     int first, last = 0;
74     int dirty;
75     int i;
76     ram_addr_t addr;
77     MemoryRegion *mem;
78 
79     i = *first_row;
80     *first_row = -1;
81 
82     mem = mem_section->mr;
83     if (!mem) {
84         return;
85     }
86 
87     addr = mem_section->offset_within_region;
88     src = memory_region_get_ram_ptr(mem) + addr;
89 
90     dest = surface_data(ds);
91     if (dest_col_pitch < 0) {
92         dest -= dest_col_pitch * (cols - 1);
93     }
94     if (dest_row_pitch < 0) {
95         dest -= dest_row_pitch * (rows - 1);
96     }
97     first = -1;
98 
99     addr += i * src_width;
100     src += i * src_width;
101     dest += i * dest_row_pitch;
102 
103     snap = memory_region_snapshot_and_clear_dirty(mem, addr, src_width * rows,
104                                                   DIRTY_MEMORY_VGA);
105     for (; i < rows; i++) {
106         dirty = memory_region_snapshot_get_dirty(mem, snap, addr, src_width);
107         if (dirty || invalidate) {
108             fn(opaque, dest, src, cols, dest_col_pitch);
109             if (first == -1)
110                 first = i;
111             last = i;
112         }
113         addr += src_width;
114         src += src_width;
115         dest += dest_row_pitch;
116     }
117     g_free(snap);
118     if (first < 0) {
119         return;
120     }
121     *first_row = first;
122     *last_row = last;
123 }
124