[SeaBIOS] [PATCH] vgabios: Support emulated text in gfx_read_char()
Kevin O'Connor
kevin at koconnor.net
Wed Jan 7 16:13:18 CET 2015
On Wed, Jan 07, 2015 at 08:50:07AM +0100, Paolo Bonzini wrote:
>
>
> On 07/01/2015 07:43, Kevin O'Connor wrote:
> > So, unless I've missed something, I don't think it impacts gwbasic.
>
> Yeah, I don't know how I missed "if (vga_emulate_text())". I guess I
> was confused by the reference to other video cards in the commit messages.
The commit message could have been worded better. I've updated it to
the below.
-Kevin
commit e638f97da08bd03c2d5be88325950d93d36911b1
Author: Kevin O'Connor <kevin at koconnor.net>
Date: Tue Jan 6 09:36:41 2015 -0500
vgabios: Support emulated text in gfx_read_char()
When emulating text mode on "coreboot framebuffer" SeaVGABIOS, return
a foreground and background attribute from gfx_read_char() and prefer
returning a space character (instead of null) on blank cells.
This also returns the foreground color (instead of always returning
zero) for regular graphics mode gfx_read_char() calls. This seems
fine as tests show other vgabios implementations also return various
values here.
Signed-off-by: Kevin O'Connor <kevin at koconnor.net>
diff --git a/vgasrc/vgafb.c b/vgasrc/vgafb.c
index 4bbbc16..1a94fcf 100644
--- a/vgasrc/vgafb.c
+++ b/vgasrc/vgafb.c
@@ -367,7 +367,7 @@ gfx_move_chars(struct vgamode_s *vmode_g, struct cursorpos dest
handle_gfx_op(&op);
}
-// Clear are of screen in graphics mode.
+// Clear area of screen in graphics mode.
static void
gfx_clear_chars(struct vgamode_s *vmode_g, struct cursorpos dest
, struct carattr ca, struct cursorpos clearsize)
@@ -469,23 +469,36 @@ gfx_read_char(struct vgamode_s *vmode_g, struct cursorpos cp)
op.op = GO_READ8;
op.x = cp.x * 8;
op.y = cp.y * cheight;
+ int car = 0;
+ u8 fgattr = 0x00, bgattr = 0x00;
+ if (vga_emulate_text()) {
+ // Read bottom right pixel of the cell to guess bg color
+ op.y += cheight-1;
+ handle_gfx_op(&op);
+ op.y -= cheight-1;
+ bgattr = op.pixels[7];
+ fgattr = bgattr ^ 0x7;
+ // Report space character for blank cells (skip null character check)
+ car = 1;
+ }
u8 i, j;
for (i=0; i<cheight; i++, op.y++) {
u8 line = 0;
handle_gfx_op(&op);
for (j=0; j<8; j++)
- if (op.pixels[j])
+ if (op.pixels[j] != bgattr) {
line |= 0x80 >> j;
+ fgattr = op.pixels[j];
+ }
lines[i] = line;
}
// Determine font
- u16 car;
- for (car=0; car<256; car++) {
+ for (; car<256; car++) {
struct segoff_s font = get_font_data(car);
if (memcmp_far(GET_SEG(SS), lines
, font.seg, (void*)(font.offset+0), cheight) == 0)
- return (struct carattr){car, 0, 0};
+ return (struct carattr){car, fgattr | (bgattr << 4), 0};
}
fail:
return (struct carattr){0, 0, 0};
@@ -594,7 +607,7 @@ vgafb_move_chars(struct cursorpos dest
, movesize.x * 2, stride, movesize.y);
}
-// Clear are of screen.
+// Clear area of screen.
void
vgafb_clear_chars(struct cursorpos dest
, struct carattr ca, struct cursorpos clearsize)
More information about the SeaBIOS
mailing list