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| author | Kevin O'Connor <kevin@koconnor.net> | 2024-04-02 13:07:58 -0400 |
|---|---|---|
| committer | Kevin O'Connor <kevin@koconnor.net> | 2024-04-05 17:59:49 -0400 |
| commit | c5a361c09a19e3b1a83557b01f11f04b27181a11 (patch) | |
| tree | a63b9a6f2f755ae233e9092615e43b122937fdf2 | |
| parent | 22c91412600b7fabd75ef68d2d4d3e63e9e27f9f (diff) | |
| download | seabios-c5a361c09a19e3b1a83557b01f11f04b27181a11.zip seabios-c5a361c09a19e3b1a83557b01f11f04b27181a11.tar.gz seabios-c5a361c09a19e3b1a83557b01f11f04b27181a11.tar.bz2 | |
stdvga: Add stdvga_set_vertical_size() helper function
Add helper function and update the bochsvga.c code to use it. This
emphasizes the relationship between stdvga_get_vertical_size() and
stdvga_set_vertical_size() code.
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
| -rw-r--r-- | vgasrc/bochsvga.c | 8 | ||||
| -rw-r--r-- | vgasrc/stdvga.c | 11 | ||||
| -rw-r--r-- | vgasrc/stdvga.h | 1 |
3 files changed, 13 insertions, 7 deletions
diff --git a/vgasrc/bochsvga.c b/vgasrc/bochsvga.c index ab8f25e..3ef0f18 100644 --- a/vgasrc/bochsvga.c +++ b/vgasrc/bochsvga.c @@ -275,13 +275,7 @@ bochsvga_set_mode(struct vgamode_s *vmode_g, int flags) stdvga_crtc_write(crtc_addr, 0x11, 0x00); stdvga_crtc_write(crtc_addr, 0x01, width / 8 - 1); stdvga_set_linelength(vmode_g, width); - stdvga_crtc_write(crtc_addr, 0x12, height - 1); - u8 v = 0; - if ((height - 1) & 0x0100) - v |= 0x02; - if ((height - 1) & 0x0200) - v |= 0x40; - stdvga_crtc_mask(crtc_addr, 0x07, 0x42, v); + stdvga_set_vertical_size(height); stdvga_crtc_write(crtc_addr, 0x09, 0x00); stdvga_crtc_mask(crtc_addr, 0x17, 0x00, 0x03); diff --git a/vgasrc/stdvga.c b/vgasrc/stdvga.c index 4bfa101..afe26db 100644 --- a/vgasrc/stdvga.c +++ b/vgasrc/stdvga.c @@ -286,6 +286,17 @@ stdvga_get_vertical_size(void) return vde + 1; } +// Set vertical screen size (number of horizontal lines in the display) +void +stdvga_set_vertical_size(int lines) +{ + u16 crtc_addr = stdvga_get_crtc(); + u16 vde = lines - 1; + stdvga_crtc_write(crtc_addr, 0x12, vde); + u8 ovl = ((vde >> 7) & 0x02) + ((vde >> 3) & 0x40); + stdvga_crtc_mask(crtc_addr, 0x07, 0x42, ovl); +} + // Get offset into framebuffer accessible from real-mode 64K segment int stdvga_get_window(struct vgamode_s *curmode_g, int window) diff --git a/vgasrc/stdvga.h b/vgasrc/stdvga.h index 1828585..ce5a80a 100644 --- a/vgasrc/stdvga.h +++ b/vgasrc/stdvga.h @@ -67,6 +67,7 @@ void stdvga_set_cursor_shape(u16 cursor_type); void stdvga_set_cursor_pos(int address); void stdvga_set_character_height(u8 lines); u16 stdvga_get_vertical_size(void); +void stdvga_set_vertical_size(int lines); int stdvga_get_window(struct vgamode_s *curmode_g, int window); int stdvga_set_window(struct vgamode_s *curmode_g, int window, int val); int stdvga_minimum_linelength(struct vgamode_s *vmode_g); |