[Intel-gfx] [PATCH] Revert "drm/i915/chv: Set min freq to efficient frequency on chv"

[Jani Nikula]

On Fri, 12 Aug 2016, deepak.s at linux.intel.com wrote:
> From: Deepak S <deepak.s at linux.intel.com>
>
> With latest Punit FW, vgg input voltag drop falling to minimum is fixed.
> So reverting the WA patch & moving to turbo freq opreation range to [RPn -> RP0]

IOW, this patch will regress for anyone who does *not* have the latest
Punit firmware. Can we check for the firmware version, and act
accordingly? How does one go about updating the firmware, if at all?

Definitely NAK until the above is cleared.

BR,
Jani.


>
> This reverts commit 5b7c91b78b1ce6663e0f1f037f6cb4d7c9537d44.
>
> commit 5b7c91b78b1ce6663e0f1f037f6cb4d7c9537d44
> Author: Deepak S <deepak.s at linux.intel.com>
> Date:   Sat May 9 18:15:46 2015 +0530
>
>     drm/i915/chv: Set min freq to efficient frequency on chv
>
> Signed-off-by: Deepak S <deepak.s at linux.intel.com>
> ---
>  drivers/gpu/drm/i915/intel_pm.c | 21 +++++++++++++++++++--
>  1 file changed, 19 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
> index 81ab119..e59799a 100644
> --- a/drivers/gpu/drm/i915/intel_pm.c
> +++ b/drivers/gpu/drm/i915/intel_pm.c
> @@ -5579,6 +5579,24 @@ static int cherryview_rps_guar_freq(struct drm_i915_private *dev_priv)
>  	return rp1;
>  }
>  
> +static int cherryview_rps_min_freq(struct drm_i915_private *dev_priv)
> +{
> +	struct drm_device *dev = &dev_priv->drm;
> +	u32 val, rpn;
> +
> +	if (dev->pdev->revision >= 0x20) {
> +		val = vlv_punit_read(dev_priv, FB_GFX_FMIN_AT_VMIN_FUSE);
> +		rpn = ((val >> FB_GFX_FMIN_AT_VMIN_FUSE_SHIFT) &
> +		       FB_GFX_FREQ_FUSE_MASK);
> +	} else { /* For pre-production hardware */
> +		val = vlv_punit_read(dev_priv, PUNIT_GPU_STATUS_REG);
> +		rpn = ((val >> PUNIT_GPU_STATIS_GFX_MIN_FREQ_SHIFT) &
> +		       PUNIT_GPU_STATUS_GFX_MIN_FREQ_MASK);
> +	}
> +
> +	return rpn;
> +}
> +
>  static int valleyview_rps_guar_freq(struct drm_i915_private *dev_priv)
>  {
>  	u32 val, rp1;
> @@ -5818,8 +5836,7 @@ static void cherryview_init_gt_powersave(struct drm_i915_private *dev_priv)
>  			 intel_gpu_freq(dev_priv, dev_priv->rps.rp1_freq),
>  			 dev_priv->rps.rp1_freq);
>  
> -	/* PUnit validated range is only [RPe, RP0] */
> -	dev_priv->rps.min_freq = dev_priv->rps.efficient_freq;
> +	dev_priv->rps.min_freq = cherryview_rps_min_freq(dev_priv);
>  	DRM_DEBUG_DRIVER("min GPU freq: %d MHz (%u)\n",
>  			 intel_gpu_freq(dev_priv, dev_priv->rps.min_freq),
>  			 dev_priv->rps.min_freq);

-- 
Jani Nikula, Intel Open Source Technology Center