Re: SVGA console

[Peter 'p2' De Schrijver]

Hi Marco,

On Wed, Aug 27, 2003 at 08:52:42PM +0200, Marco Gerards wrote:
> Hi,
> 
> "Peter 'p2' De Schrijver" <p2@mind.be> writes:
> 
> > struct syncinfo {
> >     enum { SPLIT_SYNC, CSYNC, SYNC_ON_COLOR } type;
> >     union {
> >             struct {
> >                     polarity hsync_pol;
> >                     polarity vsync_pol;
> >             } split_sync;
> >             struct {
> >                     polarity csync_pol;
> >             } csync;
> >             struct {
> >                     polarity pol;
> >                     enum {RED, GREEN, BLUE} color;
> >             } sync_on_color;
> >     } sync_parameters;
> > };
> > 
> > typedef unsigned int display_flags;
> > 
> > #define DISPLAY_FLAGS_LACE          (1<<0)
> > #define DISPLAY_FLAGS_EXTSYNC       (1<<1)
> > #define DISPLAY_FLAGS_DOUBLE        (1<<2)
> 
> Ah, thanks. I've updated the interfaces to use this. I've changed it a
> bit and added some comments, can you have a look at the new interfaces
> if this update was sane?
>  

Ok.

> [...]
> 
> > I wuould rather have :
> > error_t (*set_horiz_timings) (unsigned xres, unsigned left, unsigned
> > right, unsigned hslen);
> > 
> > /* set number of visible horizontal pixels to xres,
> >    set number of left margin pixels to left,
> >    set number of right margin pixels to right,
> >    set horizontal sync pulse width to hslen */
> 
> Yes, that is much better. I will update the interfaces soon. I haven't
> done this because it requires that all modelines will be updated (yes,
> I'm lazy :)).
> 

Ok. I guess fb.modes has all knowledge on how to do this.

> [...]
> 
> > error_t (*set_syncinfo) (struct syncinfo *si);
> > 
> > error_t (*get_syncinfo) (struct syncinfo *si);
> > 
> > error_t (*set_options) (display_flags flags);
> > 
> > error_t (*get_options) (display_flags *flags);
> 
> I've added these too. Thanks.
> 
> Thanks,
> Marco
> 
> 
> The new interfaces:
> 
> /* video-driver.h - Video driver interfaces.
>    Copyright (C) 2003 Free Software Foundation, Inc.
>    Written by Marco Gerards.
> 
>    This file is part of the GNU Hurd.
> 
>    The GNU Hurd is free software; you can redistribute it and/or
>    modify it under the terms of the GNU General Public License as
>    published by the Free Software Foundation; either version 2, or (at
>    your option) any later version.
> 
>    The GNU Hurd is distributed in the hope that it will be useful, but
>    WITHOUT ANY WARRANTY; without even the implied warranty of
>    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
>    General Public License for more details.
> 
>    You should have received a copy of the GNU General Public License
>    along with this program; if not, write to the Free Software
>    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA. */
> 
> /* The powermodes that can be used to configure the power state of the
>    monitor.  */
> 
> #ifndef _VIDEO_DRIVER_H_
> #define _VIDEO_DRIVER_H_ 1
> 
> /* DPMS powermodes.  */
> enum powermode
>   {
>     /* Normal operation.  */
>     PM_ON,
>     PM_STANDBY,
>     PM_SUSPEND,
>     /* Turn the screen off.  */
>     PM_OFF
>   };
> 
> typedef enum powermode powermode_t;
> 
> /* Use polarity to use for syncing.  */
> typedef enum polarity
>   {
>     POLARITY_LOW,
>     POLARITY_HIGH
>   } polarity_t;
> 
> /* The kind of sync signal that should be used.  */
> typedef struct syncinfo
> {

I would change line(s) to signal(s). Seems a bit more clear to me.

>   enum
>     {
>       /* The videocard use the HSYNC and VSYNC lines to inform the
>        monitor of the sync.  */
>       SPLIT_SYNC,
>       /* The monitor uses only one line for both HSYNC and VSYNC.  */
>       CSYNC,
>       /* The monitor uses no seperate line for the sync; it uses one
>        of the color lines instead.  */
>       SYNC_ON_COLOR
>     } type;
>   union
>   {
>     struct 
>     {
>       polarity_t hsync_pol;
>       polarity_t vsync_pol;
>     } split_sync;
>     struct
>     {
>       polarity_t csync_pol;
>     } csync;
>     struct
>     {
>       polarity_t pol;
>       /* The color line that is used for syncing.  */
>       enum 
>       {
>         RED,
>         GREEN, 
>         BLUE
>       } color;
>     } sync_on_color;
>   } sync_parameters;
> } syncinfo_t;
> 
> typedef unsigned int display_flags_t;
> 
> /* Use interlacing.  */
> #define DISPLAY_FLAGS_LACE    (1 << 0);
> /* Use a pixelclock from an external source (genlock?)  */

> #define DISPLAY_FLAGS_EXTSYNC (1 << 1);
> /* Use doublescan.  Every line is shown twice, used for low resolution
>    modes.  */
> #define DISPLAY_FLAGS_DOUBLE  (1 << 2);
> 
> /* Information and interfaces for a video driver.  */
> struct video_driver
> {
>   /* Name of driver name.  */
>   const char *driver_name;
> 
>   /* Name of videocard or videochipset.  This information is available
>      after initialisation with init.  It can be set to NULL when it is
>      not relevant.  */
>   char *card_sub_name;
> 
>   /* Maximum allowed values.  XXX: Are more maximum values
>      required?  */
>   int max_hdisplay_end;
>   int max_hsync_start;
>   int max_hblank_start;
>   int max_htotal;
>   int max_vdisplay_end;
>   int max_vsync_start;
>   int max_vblank_start;
>   int max_vtotal;
> 
>   /* Initialise video driver.  If the hardware is not available or
>      usable ENODEV is returned.  */
>   error_t (*init) (void);
> 
>   /* Deinitialize the driver.  */
>   error_t (*fini) (void);
> 
>   /* Set the last visible pixel on the display to END.  Set the first
>      pixel of the horizontal retrace to SYNC_START and its last pixel
>      to SYNC_END.  Set the last pixel of the screen to TOTAL, after
>      this the new line will begin.  END, SYNC_START, SYNC_END and
>      TOTAL must be multiples of 8.  Return EOVERFLOW when the hardware
>      can't setup the hardware registers without overflowing them, in
>      that case the videomode is not available.  */
>   error_t (*set_horiz_timings) (int xres, int sync_start, int sync_end,
>                               int total);
> 
>   /* Return in END the last visible pixel on the screen, in SYNC_START
>      the pixel on which the horizontal retrace starts, in SYNC_END the
>      pixel on which the horizontal retrace ends and in TOTAL the last
>      pixel of the screen.  Never return values that are not usable
>      with set_horiz_timings.  */
>   error_t (*get_horiz_timings) (int *xres, int *sync_start, int *sync_end,
>                               int *total);
> 
>   /* Set the last visible scanline on the display to END.  Set the
>      first scanline of the horizontal retrace to SYNC_START and its
>      last scanline to SYNC_END.  Set the last scanline of the screen
>      to TOTAL, after this the new vertical period will begin.  Return
>      EOVERFLOW when the hardware can't setup the hardware registers
>      without overflowing them, in that case the videomode is not
>      available.  */
>   error_t (*set_vert_timings) (int yres, int sync_start, int sync_end,
>                              int total);
> 
>   /* Return in END the last visible scanline on the screen, in
>      SYNC_START the scanline on which the horizontal retrace starts,
>      in SYNC_END the scanline on which the horizontal retrace ends and
>      in TOTAL the last scanline of the screen.  Never return values
>      that are not usable with set_vert_timings.  */
>   error_t (*get_vert_timings) (int *yres, int *sync_start, int *sync_end,
>                              int *total);
> 
>   /* Set the timer to FREQUENCY Khz, the frequency used by the
>      hardware may be DEVIATION Hhz more or less than FREQUENCY.  If
>      the pixelclock cannot be set to FREQUENCY with the deviation
>      DEVIATION return EINVAL.  */
>   error_t (*set_pixclock) (long frequency, int deviation);
> 
>   /* Test if there is a pixelclock with FREQUENCY Khz available, the
>      frequency used by the hardware may be DEVIATION Khz more or less
>      than FREQUENCY.  Return 1 if a clock is available, return 0
>      otherwise.  */
>   int (*test_pixclock) (long frequency, int deviation);
> 
>   /* Set the powermode of the monitor connected to this card to
>      POWERMODE.  If this mode is not supported, return EINVAL.  */
>   error_t (*set_powermode) (powermode_t powermode);
> 
>   /* Get the current powermode, it is guaranteed that the returned
>      powermode is setable with set_powermode.  */
>   powermode_t (*get_powermode) (void);
> 
>   /* Set the kind of syncronisation used to SI.  */
>   error_t (*set_syncinfo) (syncinfo_t *si);
> 
>   /* Get the kind of syncronisation that is used.  Return the
>      information in *SI.  SI should have been allocated by the
>      caller.  */
>   error_t (*get_syncinfo) (syncinfo_t *si);
> 
>   /* Use the options in FLAGS for producing display output.  */
>   error_t (*set_options) (display_flags_t flags);
> 
>   /* Get the currently used options and return them in FLAGS.  */
>   error_t (*get_options) (display_flags_t *flags);
> };
> 
> typedef struct video_driver *video_driver_t;
> 
> 
> /* Available video drivers.  */
> 
> /* The video driver that is used.  This is one of the drivers
>    below.  */
> video_driver_t video_driver;
> 
> /* The VGA driver.  It only supports the minimal VGA hardware, a 25
>    and 28 Mhz clock.  This driver is also used by other drivers for
>    SVGA cards.  */
> extern const video_driver_t video_driver_vga;
> 
> /* The driver for S3 videochips.  Only the S3 Trio is currently
>    supported, this chipset has a programmable clock.  */
> extern const video_driver_t video_driver_s3;
> 

Cheers,

Peter.