Re: [PATCH 11/24] drm/i915: program WM_LINETIME on Haswell

[Jesse Barnes <jbarnes@virtuousgeek.org>]

On Thu, 26 Apr 2012 15:21:06 -0300
Eugeni Dodonov <eugeni.dodonov@intel.com> wrote:

> The line time can be programmed according to the number of horizontal
> pixels vs effective pixel rate ratio.
> 
> v2: improve comment as per Chris Wilson suggestion
> 
> v3: incorporate latest changes in specs.
> 
> Signed-off-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
> ---
>  drivers/gpu/drm/i915/intel_display.c |   13 +++++++++++++
>  1 file changed, 13 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index ea1ac15..8308da0 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -4555,6 +4555,19 @@ static int ironlake_crtc_mode_set(struct drm_crtc *crtc,
>  		   (adjusted_mode->crtc_vsync_start - 1) |
>  		   ((adjusted_mode->crtc_vsync_end - 1) << 16));
>  
> +	if (IS_HASWELL(dev)) {
> +		temp = I915_READ(PIPE_WM_LINETIME(pipe));
> +		temp &= ~PIPE_WM_LINETIME_MASK;
> +
> +		/* The WM are computed with base on how long it takes to fill a single
> +		 * row at the given clock rate, multiplied by 8.
> +		 * */
> +		temp |= PIPE_WM_LINETIME_TIME(
> +			((adjusted_mode->crtc_hdisplay * 1000) / adjusted_mode->clock) * 8);
> +
> +		I915_WRITE(PIPE_WM_LINETIME(pipe), temp);
> +	}
> +
>  	/* pipesrc controls the size that is scaled from, which should
>  	 * always be the user's requested size.
>  	 */

We need to set the IPS line time as well, and can we do it in the WM
functions instead?

-- 
Jesse Barnes, Intel Open Source Technology Center