X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?a=blobdiff_plain;f=kern%2Fsrc%2Fvid.c;fp=kern%2Fsrc%2Fvid.c;h=f4eb723b1f58be784538474dceb890d0e56512df;hb=4c01dc176867a3486bf2bc4287343a14b891650f;hp=0000000000000000000000000000000000000000;hpb=d67095d0b91873967843394eb090f13e847c1e2d;p=eightysix

diff --git a/kern/src/vid.c b/kern/src/vid.c
new file mode 100644
index 0000000..f4eb723
--- /dev/null
+++ b/kern/src/vid.c
@@ -0,0 +1,255 @@
+#include <string.h>
+#include "vid.h"
+#include "asmutil.h"
+
+#define CRTC_ADDR_PORT	(iobase | 4)
+#define CRTC_DATA_PORT	(iobase | 5)
+
+/* CRTC registers */
+#define CRTC_START_H	0x0c
+#define CRTC_START_L	0x0d
+#define CRTC_CURPOS_H	0x0e
+#define CRTC_CURPOS_L	0x0f
+
+static void detect_video(void);
+static int detect_vgainfo(void);
+static int detect_egainfo(void);
+static void detect_eqlist(void);
+static void crtc_write(int reg, unsigned char val);
+
+//struct console con_vid = { con_clear, con_putc, 0 };
+
+static uint16_t __far *vmem;
+static int iobase;
+
+static uint16_t cur_attr;
+static int cur_x, cur_y;
+static int cur_scroll;
+static int mono;
+
+void vid_init(void)
+{
+	detect_video();
+	if(mono) {
+		vmem = MK_FP(0xb000, 0);
+		iobase = 0x3b0;
+	} else {
+		vmem = MK_FP(0xb800, 0);
+		iobase = 0x3d0;
+	}
+
+	vid_reset();
+}
+
+static void detect_video(void)
+{
+	mono = 0;
+	vid_type = VID_UNK;
+
+	if(detect_vgainfo() == 0) {
+		return;
+	}
+	if(detect_egainfo() == 0) {
+		return;
+	}
+	detect_eqlist();
+}
+
+static int detect_vgainfo(void)
+{
+	union regs regs;
+
+	regs.w.ax = 0x1a00;
+	int86(0x10, &regs, &regs);
+	if(regs.h.al != 0x1a) {
+		return -1;
+	}
+
+	switch(regs.h.bl) {
+	case 1:
+		vid_type = VID_MDA;
+		mono = 1;
+		break;
+	case 2:
+		vid_type = VID_CGA;
+		break;
+	case 4:
+		vid_type = VID_EGA;
+		break;
+	case 5:
+		vid_type = VID_EGA;
+		mono = 1;
+		break;
+	case 6:
+		vid_type = VID_PGA;
+		break;
+	case 7:
+		vid_type = VID_VGA;
+		mono = 1;
+		break;
+	case 8:
+		vid_type = VID_VGA;
+		break;
+	case 0xa:
+	case 0xc:
+		vid_type = VID_MCGA;
+		break;
+	case 0xb:
+		vid_type = VID_MCGA;
+		mono = 1;
+		break;
+	default:
+		return -1;
+	}
+	return 0;
+}
+
+static int detect_egainfo(void)
+{
+	union regs regs;
+
+	regs.w.ax = 0x1200;
+	regs.w.bx = 0xff10;
+	int86(0x10, &regs, &regs);
+	if(regs.h.bh == 0xff) {
+		return -1;
+	}
+
+	vid_type = VID_EGA;
+	mono = regs.h.bh;
+	return 0;
+}
+
+static void detect_eqlist(void)
+{
+	union regs regs;
+
+	int86(0x11, &regs, &regs);
+	switch(regs.w.ax & 0x30) {
+	case 0:
+		vid_type = VID_EGA;
+		break;
+
+	case 0x10:
+	case 0x20:
+		vid_type = VID_CGA;
+		break;
+
+	case 0x30:
+		vid_type = VID_MDA;
+		mono = 1;
+		break;
+	}
+}
+
+void vid_reset(void)
+{
+	vid_fgcolor(WHITE);
+	vid_bgcolor(BLACK);
+	vid_scroll(0);
+	vid_setcursor(0, 0);
+	fmemset(vmem, 0, 80 * 25 * 2);
+}
+
+void vid_clearline(int row)
+{
+	int i;
+	uint16_t __far *ptr;
+
+	row += cur_scroll;
+
+	ptr = vmem + row * 80;
+	for(i=0; i<80; i++) {
+		ptr[i] = cur_attr;
+	}
+
+	if(row - 32 >= 0) {
+		/* write a copy to wrap-around future scrolling */
+		ptr -= 80 * 32;
+		for(i=0; i<80; i++) {
+			ptr[i] = cur_attr;
+		}
+	}
+}
+
+void vid_clear(void)
+{
+	int i;
+	for(i=0; i<25; i++) {
+		vid_clearline(i);
+	}
+}
+
+void vid_scroll(int line)
+{
+	int offs;
+	cur_scroll = line & 0x1f;
+	offs = cur_scroll * 80;
+	crtc_write(CRTC_START_H, offs >> 8);
+	crtc_write(CRTC_START_L, offs);
+}
+
+void vid_setcursor(int x, int y)
+{
+	int loc = (y + cur_scroll) * 80 + x;
+	cur_x = x;
+	cur_y = y;
+	crtc_write(CRTC_CURPOS_H, loc >> 8);
+	crtc_write(CRTC_CURPOS_L, loc);
+}
+
+void vid_fgcolor(int color)
+{
+	cur_attr = (cur_attr & 0xf0) | color;
+}
+
+void vid_bgcolor(int color)
+{
+	cur_attr = (cur_attr & 0x0f) | (color << 4);
+}
+
+void vid_glyph(int x, int y, int c, int attr)
+{
+	uint16_t __far *ptr;
+	uint16_t val = (c & 0xff) | attr;
+
+	y += cur_scroll;
+
+	ptr = vmem + y * 80 + x;
+	*ptr = val;
+
+	if(y - 32 >= 0) {
+		/* write a copy to wrap-around future scrolling */
+		ptr -= 80 * 32;
+		*ptr = val;
+	}
+}
+
+void vid_text(int x, int y, const char *s, int attr)
+{
+	int len = 0;
+	uint16_t __far *ptr;
+
+	y += cur_scroll;
+
+	ptr = vmem + y * 80 + x;
+	while(*s) {
+		*ptr++ = (*s++ & 0xff) | attr;
+		len++;
+	}
+
+	if(y - 32 >= 0) {
+		/* write a copy to wrap-around future scrolling */
+		ptr -= 80 * 32 + len;
+		s -= len;
+		while(*s) {
+			*ptr++ = (*s++ & 0xff) | attr;
+		}
+	}
+}
+
+static void crtc_write(int reg, unsigned char val)
+{
+	outp(CRTC_ADDR_PORT, reg);
+	outp(CRTC_DATA_PORT, val);
+}