[PATCH] drm/edid : cache edid range limits in drm connector

[Prosyak, Vitaly]

We are going to use min/max vertical refresh rate when enter/exit to the dynamic refresh rate mode ,it  is known as 'freesync', enter/exit to full screen games.
Right , we may have a helper function which extracts these properties and store wherever need it.
But this an alternative solution  with additional helper adds some code duplication into drm_edid.c  since the case already present in the code:
case 0x01: /* just the ranges, no formula */
Also these values are parsed during each mode enumeration.

Why I put into connector: 
Drm connector have already similar items from EDID: drm_tile_group ,etc...

Vitaly
-----Original Message-----.

From: Daniel Vetter [mailto:daniel.vetter at ffwll.ch] On Behalf Of Daniel Vetter
Sent: Tuesday, May 03, 2016 4:24 PM
To: Prosyak, Vitaly
Cc: dri-devel at lists.freedesktop.org
Subject: Re: [PATCH] drm/edid : cache edid range limits in drm connector

On Tue, May 03, 2016 at 11:05:24AM -0400, Vitaly Prosyak wrote:
> Cache in drm connector the edid range limits properties:
> min/max vertical refresh rates and max pixel clock.
> It would be used when enter to drr mode.
> 
> Signed-off-by: Vitaly Prosyak <vitaly.prosyak at amd.com>

Where's the patches that will use this? It might make sense to instead have some helper functions to compute these values, so that drivers can store them wherever they want/need. But impossible to tell without the users of this stuff.
-Daniel

> ---
>  drivers/gpu/drm/drm_edid.c | 11 +++++++++++
>  include/drm/drm_crtc.h     |  5 +++++
>  2 files changed, 16 insertions(+)
> 
> diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c 
> index 04cb487..7e49962 100644
> --- a/drivers/gpu/drm/drm_edid.c
> +++ b/drivers/gpu/drm/drm_edid.c
> @@ -2190,6 +2190,17 @@ do_inferred_modes(struct detailed_timing *timing, void *c)
>  							  timing);
>  		break;
>  	case 0x01: /* just the ranges, no formula */
> +		closure->connector->min_vfreq = range->min_vfreq;
> +		closure->connector->max_vfreq = range->max_vfreq;
> +		if (closure->edid->revision >= 4) {
> +			if ((range->flags & 0x03) == 0x3)
> +				closure->connector->min_vfreq += 255;
> +			if (range->flags & 0x02)
> +				closure->connector->max_vfreq += 255;
> +		}
> +		closure->connector->max_pixel_clock_khz =
> +			range_pixel_clock(closure->edid, (u8 *)timing);
> +		break;
>  	default:
>  		break;
>  	}
> diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h index 
> c5b4b81..85fc554 100644
> --- a/include/drm/drm_crtc.h
> +++ b/include/drm/drm_crtc.h
> @@ -1230,6 +1230,11 @@ struct drm_connector {
>  	uint8_t num_h_tile, num_v_tile;
>  	uint8_t tile_h_loc, tile_v_loc;
>  	uint16_t tile_h_size, tile_v_size;
> +
> +	/*EDID range limits for drr*/
> +	int min_vfreq ;
> +	int max_vfreq ;
> +	int max_pixel_clock_khz;
>  };
>  
>  /**
> --
> 1.9.1
> 
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> dri-devel at lists.freedesktop.org
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--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch