Re: 16-bit depth on radeonfb

[Julian Coleman <jdc%coris.org.uk@localhost>]

Hi,

> 16-bit depth makes hardware with limited memory and/or memory bandwidth
> much more usable and useful. The following patch adds this to radeonfb.

I think that's OK, apart from:

> --- ./dev/pci/radeonfb.c.orig
> +++ ./dev/pci/radeonfb.c
> @@ -104,7 +104,8 @@
>  #ifdef RADEONFB_DEPTH_32
>  #define RADEONFB_DEFAULT_DEPTH 32
>  #else
> -#define RADEONFB_DEFAULT_DEPTH 8
> +/* #define RADEONFB_DEFAULT_DEPTH 8 */
> +#define RADEONFB_DEFAULT_DEPTH 16
>  #endif
>  
>  static int radeonfb_match(device_t, cfdata_t, void *);

where we change the default depth from 8 to 16.  We already have the flag
to set RADEONFB_DEPTH_32, e.g. on alpha:

  https://nxr.netbsd.org/search?q=RADEONFB_DEPTH_32&project=src&defs=&refs=&path=&hist=
  https://nxr.netbsd.org/xref/src/sys/arch/alpha/conf/GENERIC#342

so I would suggest adding a RADEONFB_DEPTH_16 flag too and setting it in
your kernel config.  It might make sense for it to be the default, although
I'm not sure - which arch are you running on?

Regards,

Julian

PS.  Of course, we have multiple ways of doing this, so you could also add
flags on the device line itself:

  https://nxr.netbsd.org/xref/src/sys/arch/alpha/conf/GENERIC#539
  https://nxr.netbsd.org/xref/src/sys/dev/i2c/at24cxx.c#180
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