Commit df800210 authored by malc's avatar malc
Browse files

Revert "vga: add some optional CGA compatibility hacks"

This reverts commit 482f7bf8

.
Signed-off-by: default avatarmalc <av1474@comtv.ru>
parent 4f213879
......@@ -176,10 +176,6 @@ enum vga_retrace_method {
extern enum vga_retrace_method vga_retrace_method;
#define VGA_CGA_HACK_PALETTE_BLANKING (1<<0)
#define VGA_CGA_HACK_FONT_HEIGHT (1<<1)
extern int vga_cga_hacks;
static inline DeviceState *isa_vga_init(ISABus *bus)
{
ISADevice *dev;
......
......@@ -547,31 +547,14 @@ void vga_ioport_write(void *opaque, uint32_t addr, uint32_t val)
printf("vga: write CR%x = 0x%02x\n", s->cr_index, val);
#endif
/* handle CR0-7 protection */
if (s->cr[VGA_CRTC_V_SYNC_END] & VGA_CR11_LOCK_CR0_CR7) {
if (s->cr_index <= VGA_CRTC_OVERFLOW) {
/* can always write bit 4 of CR7 */
if (s->cr_index == VGA_CRTC_OVERFLOW) {
s->cr[VGA_CRTC_OVERFLOW] =
(s->cr[VGA_CRTC_OVERFLOW] & ~0x10) | (val & 0x10);
}
return;
} else if ((vga_cga_hacks & VGA_CGA_HACK_FONT_HEIGHT) &&
!(s->sr[VGA_SEQ_CLOCK_MODE] & VGA_SR01_CHAR_CLK_8DOTS)) {
/* extra CGA compatibility hacks (not in standard VGA) */
if (s->cr_index == VGA_CRTC_MAX_SCAN &&
val == 7 &&
(s->cr[VGA_CRTC_MAX_SCAN] & 0xf) == 0xf) {
return;
} else if (s->cr_index == VGA_CRTC_CURSOR_START &&
val == 6 &&
(s->cr[VGA_CRTC_MAX_SCAN] & 0xf) == 0xf) {
val = 0xd;
} else if (s->cr_index == VGA_CRTC_CURSOR_END &&
val == 7 &&
(s->cr[VGA_CRTC_MAX_SCAN] & 0xf) == 0xf) {
val = 0xe;
}
if ((s->cr[VGA_CRTC_V_SYNC_END] & VGA_CR11_LOCK_CR0_CR7) &&
s->cr_index <= VGA_CRTC_OVERFLOW) {
/* can always write bit 4 of CR7 */
if (s->cr_index == VGA_CRTC_OVERFLOW) {
s->cr[VGA_CRTC_OVERFLOW] = (s->cr[VGA_CRTC_OVERFLOW] & ~0x10) |
(val & 0x10);
}
return;
}
s->cr[s->cr_index] = val;
......@@ -1903,10 +1886,7 @@ static void vga_update_display(void *opaque)
/* nothing to do */
} else {
full_update = 0;
if (!(s->ar_index & 0x20) &&
/* extra CGA compatibility hacks (not in standard VGA */
(!(vga_cga_hacks & VGA_CGA_HACK_PALETTE_BLANKING) ||
(s->ar_index != 0 && s->ar_flip_flop))) {
if (!(s->ar_index & 0x20)) {
graphic_mode = GMODE_BLANK;
} else {
graphic_mode = s->gr[VGA_GFX_MISC] & VGA_GR06_GRAPHICS_MODE;
......
......@@ -975,25 +975,6 @@ Valid optional properties are
@item retrace=dumb|precise
Select dumb (default) or precise VGA retrace logic, useful for some
DOS games/demos.
@item cga_hacks=@var{hack1}[+@var{hack2},[...]]
Enable various extra CGA compatibility hacks for programs that are
trying to directly set CGA modes without BIOS assistance nor
real knowledge of EGA/VGA. These might only work with -vga std.
Valid hacks are
@table @option
@item palette_blanking
Wait to blank the screen until palette registers seem to actually be
modified, instead of blanking it as soon as the palette address bit (0x10)
of the attribute address register (0x3c0) is cleared.
@item font_height
Ignore attempts to change the VGA font height (index 9),
cursor start (index 10), and cursor end (index 11) of the CRTC control
registers (0x3d5) if trying to set them to the default for CGA fonts
instead of VGA fonts.
@item all
Enable all CGA hacks. More CGA hacks may be added in future versions
of qemu.
@end table
@end table
ETEXI
......
......@@ -179,7 +179,6 @@ int main(int argc, char **argv)
static const char *data_dir;
const char *bios_name = NULL;
enum vga_retrace_method vga_retrace_method = VGA_RETRACE_DUMB;
int vga_cga_hacks = 0;
DisplayType display_type = DT_DEFAULT;
int display_remote = 0;
const char* keyboard_layout = NULL;
......@@ -1749,28 +1748,6 @@ static void select_vgahw (const char *p)
else if (strstart(opts, "precise", &nextopt))
vga_retrace_method = VGA_RETRACE_PRECISE;
else goto invalid_vga;
} else if (strstart(opts, ",cga_hacks=", &nextopt)) {
opts = nextopt;
while (*opts) {
if (strstart(opts, "all", &nextopt)) {
opts = nextopt;
vga_cga_hacks |= ~0;
} else if (strstart(opts, "palette_blanking", &nextopt)) {
opts = nextopt;
vga_cga_hacks |= VGA_CGA_HACK_PALETTE_BLANKING;
} else if (strstart(opts, "font_height", &nextopt)) {
opts = nextopt;
vga_cga_hacks |= VGA_CGA_HACK_FONT_HEIGHT;
} else {
break;
}
if (*opts == '+') {
opts++;
} else {
break;
}
}
} else goto invalid_vga;
opts = nextopt;
}
......
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment