From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:46357) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SmSPh-00046B-4M for qemu-devel@nongnu.org; Wed, 04 Jul 2012 12:26:53 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1SmSPa-0006pU-76 for qemu-devel@nongnu.org; Wed, 04 Jul 2012 12:26:48 -0400 Received: from v220110690675601.yourvserver.net ([78.47.199.172]:39806) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SmSPZ-0006pE-Sj for qemu-devel@nongnu.org; Wed, 04 Jul 2012 12:26:42 -0400 Message-ID: <4FF46EBA.3000105@weilnetz.de> Date: Wed, 04 Jul 2012 18:26:34 +0200 From: Stefan Weil MIME-Version: 1.0 References: <4FF159B2.4010405@siemens.com> <4FF447B9.2010103@siemens.com> In-Reply-To: <4FF447B9.2010103@siemens.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v2] vga: Implement blinking of text cursor List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Jan Kiszka Cc: Blue Swirl , Javier Donoso , Anthony Liguori , qemu-devel Hi Jan, please see my comments below. Am 04.07.2012 15:40, schrieb Jan Kiszka: > Let the text cursor blink at 5 Hz. No timer is used, instead we rely on > the fact that the display is updated periodically. > > Signed-off-by: Jan Kiszka > --- > > Changes in v2: > - avoid full screen updates for cursor blinking > - convert cursor_blink_state to cursor_visible_phase > > 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..a1644f3 100644 > --- a/hw/vga.c > +++ b/hw/vga.c > @@ -38,6 +38,8 @@ > > //#define DEBUG_BOCHS_VBE > > +#define VGA_TEXT_CURSOR_PERIOD 200 > + > /* > * Video Graphics Array (VGA) > * > @@ -1300,6 +1302,7 @@ 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 +1373,10 @@ 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; > + s->cursor_visible_phase = !s->cursor_visible_phase; > + } > It's named VGA_TEXT_CURSOR_PERIOD, but it looks like it is not the period, but the time for each of two states (on/off), so it's 1/2 the period. With your patch, I'd expect a blink frequency of 2.5 Hz. According to the VGA documentation (I used http://www.stanford.edu/class/cs140/projects/pintos/specs/freevga/vga/textcur.htm#blink), the time for each state should be 16 / (60 Hz) or 266 ms resulting in a blink frequency of 1.875 Hz. > > depth_index = get_depth_index(s->ds); > if (cw == 16) > @@ -1390,7 +1397,7 @@ 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 +1427,8 @@ 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 +1892,8 @@ 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) + VGA_TEXT_CURSOR_PERIOD; > 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); > As far as I can tell, there are more cursor features missing: do we support an invisible cursor (your patch doesn't) or cursor shape? See also this URL for more information: http://www.stanford.edu/class/cs140/projects/pintos/specs/freevga/vga/textcur.htm Blinking is also missing for text with the blink attribute. I don't know whether real hardware synchronizes text and cursor blinking. If it does, we should do that, too. What about vertical blank interrupt? It is the base of text cursor blinking. We don't support it currently. Regards, Stefan