Patchwork [v3] vga: Implement blinking of text cursor

login
register
mail settings
Submitter Jan Kiszka
Date July 4, 2012, 5:49 p.m.
Message ID <4FF48242.4060108@siemens.com>
Download mbox | patch
Permalink /patch/169031/
State New
Headers show

Comments

Jan Kiszka - July 4, 2012, 5:49 p.m.
Let the text cursor blink at 1.875 Hz, the original VGA cursor
frequency. No timer is used, instead we rely on the fact that the
display is updated periodically.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
---

Changes in v3:
 - adjusted frequency to original value
 - fixed semantic of VGA_TEXT_CURSOR_PERIOD_MS

 hw/vga.c     |   14 ++++++++++++--
 hw/vga_int.h |    2 ++
 2 files changed, 14 insertions(+), 2 deletions(-)
Blue Swirl - July 14, 2012, 12:18 p.m.
Thanks, applied.

On Wed, Jul 4, 2012 at 5:49 PM, Jan Kiszka <jan.kiszka@siemens.com> wrote:
> Let the text cursor blink at 1.875 Hz, the original VGA cursor
> frequency. No timer is used, instead we rely on the fact that the
> display is updated periodically.
>
> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
> ---
>
> Changes in v3:
>  - adjusted frequency to original value
>  - fixed semantic of VGA_TEXT_CURSOR_PERIOD_MS
>
>  hw/vga.c     |   14 ++++++++++++--
>  hw/vga_int.h |    2 ++
>  2 files changed, 14 insertions(+), 2 deletions(-)
>
> diff --git a/hw/vga.c b/hw/vga.c
> index acb3f7d..f82ced8 100644
> --- a/hw/vga.c
> +++ b/hw/vga.c
> @@ -38,6 +38,9 @@
>
>  //#define DEBUG_BOCHS_VBE
>
> +/* 16 state changes per vertical frame @60 Hz */
> +#define VGA_TEXT_CURSOR_PERIOD_MS       (1000 * 2 * 16 / 60)
> +
>  /*
>   * Video Graphics Array (VGA)
>   *
> @@ -1300,6 +1303,7 @@ static void vga_draw_text(VGACommonState *s, int full_update)
>      uint32_t *ch_attr_ptr;
>      vga_draw_glyph8_func *vga_draw_glyph8;
>      vga_draw_glyph9_func *vga_draw_glyph9;
> +    int64_t now = qemu_get_clock_ms(vm_clock);
>
>      /* compute font data address (in plane 2) */
>      v = s->sr[VGA_SEQ_CHARACTER_MAP];
> @@ -1370,6 +1374,10 @@ static void vga_draw_text(VGACommonState *s, int full_update)
>          s->cursor_end = s->cr[VGA_CRTC_CURSOR_END];
>      }
>      cursor_ptr = s->vram_ptr + (s->start_addr + cursor_offset) * 4;
> +    if (now >= s->cursor_blink_time) {
> +        s->cursor_blink_time = now + VGA_TEXT_CURSOR_PERIOD_MS / 2;
> +        s->cursor_visible_phase = !s->cursor_visible_phase;
> +    }
>
>      depth_index = get_depth_index(s->ds);
>      if (cw == 16)
> @@ -1390,7 +1398,7 @@ static void vga_draw_text(VGACommonState *s, int full_update)
>          cx_max = -1;
>          for(cx = 0; cx < width; cx++) {
>              ch_attr = *(uint16_t *)src;
> -            if (full_update || ch_attr != *ch_attr_ptr) {
> +            if (full_update || ch_attr != *ch_attr_ptr || src == cursor_ptr) {
>                  if (cx < cx_min)
>                      cx_min = cx;
>                  if (cx > cx_max)
> @@ -1420,7 +1428,8 @@ static void vga_draw_text(VGACommonState *s, int full_update)
>                                      font_ptr, cheight, fgcol, bgcol, dup9);
>                  }
>                  if (src == cursor_ptr &&
> -                    !(s->cr[VGA_CRTC_CURSOR_START] & 0x20)) {
> +                    !(s->cr[VGA_CRTC_CURSOR_START] & 0x20) &&
> +                    s->cursor_visible_phase) {
>                      int line_start, line_last, h;
>                      /* draw the cursor */
>                      line_start = s->cr[VGA_CRTC_CURSOR_START] & 0x1f;
> @@ -1884,6 +1893,7 @@ static void vga_update_display(void *opaque)
>          }
>          if (graphic_mode != s->graphic_mode) {
>              s->graphic_mode = graphic_mode;
> +            s->cursor_blink_time = qemu_get_clock_ms(vm_clock);
>              full_update = 1;
>          }
>          switch(graphic_mode) {
> diff --git a/hw/vga_int.h b/hw/vga_int.h
> index 3b38764..8938093 100644
> --- a/hw/vga_int.h
> +++ b/hw/vga_int.h
> @@ -156,6 +156,8 @@ typedef struct VGACommonState {
>      uint32_t last_scr_width, last_scr_height; /* in pixels */
>      uint32_t last_depth; /* in bits */
>      uint8_t cursor_start, cursor_end;
> +    bool cursor_visible_phase;
> +    int64_t cursor_blink_time;
>      uint32_t cursor_offset;
>      unsigned int (*rgb_to_pixel)(unsigned int r,
>                                   unsigned int g, unsigned b);
> --
> 1.7.3.4

Patch

diff --git a/hw/vga.c b/hw/vga.c
index acb3f7d..f82ced8 100644
--- a/hw/vga.c
+++ b/hw/vga.c
@@ -38,6 +38,9 @@ 
 
 //#define DEBUG_BOCHS_VBE
 
+/* 16 state changes per vertical frame @60 Hz */
+#define VGA_TEXT_CURSOR_PERIOD_MS       (1000 * 2 * 16 / 60)
+
 /*
  * Video Graphics Array (VGA)
  *
@@ -1300,6 +1303,7 @@  static void vga_draw_text(VGACommonState *s, int full_update)
     uint32_t *ch_attr_ptr;
     vga_draw_glyph8_func *vga_draw_glyph8;
     vga_draw_glyph9_func *vga_draw_glyph9;
+    int64_t now = qemu_get_clock_ms(vm_clock);
 
     /* compute font data address (in plane 2) */
     v = s->sr[VGA_SEQ_CHARACTER_MAP];
@@ -1370,6 +1374,10 @@  static void vga_draw_text(VGACommonState *s, int full_update)
         s->cursor_end = s->cr[VGA_CRTC_CURSOR_END];
     }
     cursor_ptr = s->vram_ptr + (s->start_addr + cursor_offset) * 4;
+    if (now >= s->cursor_blink_time) {
+        s->cursor_blink_time = now + VGA_TEXT_CURSOR_PERIOD_MS / 2;
+        s->cursor_visible_phase = !s->cursor_visible_phase;
+    }
 
     depth_index = get_depth_index(s->ds);
     if (cw == 16)
@@ -1390,7 +1398,7 @@  static void vga_draw_text(VGACommonState *s, int full_update)
         cx_max = -1;
         for(cx = 0; cx < width; cx++) {
             ch_attr = *(uint16_t *)src;
-            if (full_update || ch_attr != *ch_attr_ptr) {
+            if (full_update || ch_attr != *ch_attr_ptr || src == cursor_ptr) {
                 if (cx < cx_min)
                     cx_min = cx;
                 if (cx > cx_max)
@@ -1420,7 +1428,8 @@  static void vga_draw_text(VGACommonState *s, int full_update)
                                     font_ptr, cheight, fgcol, bgcol, dup9);
                 }
                 if (src == cursor_ptr &&
-                    !(s->cr[VGA_CRTC_CURSOR_START] & 0x20)) {
+                    !(s->cr[VGA_CRTC_CURSOR_START] & 0x20) &&
+                    s->cursor_visible_phase) {
                     int line_start, line_last, h;
                     /* draw the cursor */
                     line_start = s->cr[VGA_CRTC_CURSOR_START] & 0x1f;
@@ -1884,6 +1893,7 @@  static void vga_update_display(void *opaque)
         }
         if (graphic_mode != s->graphic_mode) {
             s->graphic_mode = graphic_mode;
+            s->cursor_blink_time = qemu_get_clock_ms(vm_clock);
             full_update = 1;
         }
         switch(graphic_mode) {
diff --git a/hw/vga_int.h b/hw/vga_int.h
index 3b38764..8938093 100644
--- a/hw/vga_int.h
+++ b/hw/vga_int.h
@@ -156,6 +156,8 @@  typedef struct VGACommonState {
     uint32_t last_scr_width, last_scr_height; /* in pixels */
     uint32_t last_depth; /* in bits */
     uint8_t cursor_start, cursor_end;
+    bool cursor_visible_phase;
+    int64_t cursor_blink_time;
     uint32_t cursor_offset;
     unsigned int (*rgb_to_pixel)(unsigned int r,
                                  unsigned int g, unsigned b);