]> Joshua Wise's Git repositories - netwatch.git/blame_incremental - video/text.c
Be more correct in grabbing fonts from VRAM.
[netwatch.git] / video / text.c
... / ...
CommitLineData
1#include <io.h>
2#include <text.h>
3#include <paging.h>
4#include <minilib.h>
5#include <stdint.h>
6#include <output.h>
7#include <smram.h>
8#include <crc32.h>
9#include <video_defines.h>
10
11static unsigned char _font[256 * 32];
12
13/* XXX reunify this with vga-overlay? */
14#define VRAM_BASE 0xA0000UL
15#define TEXT_CONSOLE_OFFSET 0x18000UL
16
17#define TEXT_CONSOLE_BASE (VRAM_BASE + TEXT_CONSOLE_OFFSET)
18
19static unsigned char vga_read(unsigned char idx)
20{
21 outb(CRTC_IDX_REG, idx);
22 return inb(CRTC_DATA_REG);
23}
24
25static char * vga_base()
26{
27 return (char *) (
28 TEXT_CONSOLE_BASE
29 + (((unsigned int) vga_read(CRTC_START_ADDR_MSB_IDX)) << 9)
30 + (((unsigned int) vga_read(CRTC_START_ADDR_LSB_IDX)) << 1)
31 );
32}
33
34/* Must be called from a firstrun context, where we don't care about saving
35 * 0x3CE state. */
36void text_init()
37{
38 unsigned char oldread;
39
40 smram_state_t old_state = smram_save_state();
41 outb(0x3CE, 0x06 /* Miscellaneous */);
42 outb(0x3CF, 0x0C);
43 outb(0x3C4, 0x04 /* Seq memory mode */);
44 outb(0x3C5, inb(0x3C5) | 0x04);
45 outb(0x3CE, 0x05 /* Mode */);
46 outb(0x3CF, inb(0x3CF) & ~0x10);
47 outb(0x3CE, 0x04 /* Read register */);
48 oldread = inb(0x3CF);
49 outb(0x3CF, 0x02 /* Font plane */);
50
51 smram_aseg_set_state(SMRAM_ASEG_SMMCODE);
52 memcpy(_font, p2v(0xB8000), sizeof(_font));
53 smram_restore_state(old_state);
54
55 outb(0x3CF, oldread);
56 outb(0x3CE, 0x06 /* Miscellaneous */);
57 outb(0x3CF, 0x0E);
58 outb(0x3CE, 0x05 /* Mode */);
59 outb(0x3CF, inb(0x3CF) | 0x10);
60 outb(0x3C4, 0x04 /* Seq memory mode */);
61 outb(0x3C5, inb(0x3C5) & ~0x04);
62}
63
64void text_render(char *buf, int x, int y, int w, int h)
65{
66 unsigned char *video = (unsigned char *)vga_base();
67 unsigned int textx = x / 9;
68 unsigned int texty = y / 16;
69 unsigned int cx, cy;
70 unsigned char ch, at, font;
71 smram_state_t old_state = smram_save_state();
72
73 outputf("text_render: (%d,%d),(%d,%d)", x, y, w, h);
74
75 smram_aseg_set_state(SMRAM_ASEG_SMMCODE);
76 for (cy = y; cy < (y + h); cy++)
77 {
78 cx = x;
79 texty = cy / 16;
80 textx = cx / 9;
81 ch = video[texty * 160 + textx * 2];
82 at = video[texty * 160 + textx * 2 + 1];
83 font = _font[ch * 32 + cy % 16];
84 for (cx = x; cx < (x + w); cx++)
85 {
86 unsigned int pos = cx % 9;
87 if (pos == 0)
88 {
89 textx = cx / 9;
90 ch = video[texty * 160 + textx * 2];
91 at = video[texty * 160 + textx * 2 + 1];
92 font = _font[ch * 32 + cy % 16];
93 }
94 /* XXX always BGR888 */
95 if (pos == 8) /* 9th pixel is cloned */
96 pos = 7;
97 if ((font >> (7 - pos)) & 1)
98 {
99 *(buf++) = (at & 0x01) ? 0xFF : 0x00;
100 *(buf++) = (at & 0x02) ? 0xFF : 0x00;
101 *(buf++) = (at & 0x04) ? 0xFF : 0x00;
102 } else {
103 *(buf++) = (at & 0x10) ? 0xFF : 0x00;
104 *(buf++) = (at & 0x20) ? 0xFF : 0x00;
105 *(buf++) = (at & 0x40) ? 0xFF : 0x00;
106 }
107 *(buf++) = 0;
108 }
109 }
110 smram_restore_state(old_state);
111}
112
113uint32_t text_checksum(int x, int y, int w, int h)
114{
115 unsigned char *video = (unsigned char *)vga_base();
116 unsigned int textx = x / 9;
117 unsigned int texty = y / 16;
118 int cx, cy;
119 uint32_t cksm = 0;
120 smram_state_t old_state = smram_save_state();
121
122 smram_aseg_set_state(SMRAM_ASEG_SMMCODE);
123
124 for (cy = y; cy < (y + h); cy++)
125 {
126 cx = x;
127 texty = cy / 16;
128 textx = cx / 9;
129 cksm = crc32(video + texty * 160 + textx * 2, (w / 9) * 2 + 2, cksm); /* Err on the side of 'too many'. */
130 }
131
132 smram_restore_state(old_state);
133
134 return cksm;
135}
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