Re: [PATCH 01/11] drm/i915: Change vlv cdclk to use kHz units

Jesse Barnes
2014-06-25T18:35:28Z

On Fri, 13 Jun 2014 13:37:47 +0300
ville.syrjala@linux.intel.com wrote:

> From: Ville Syrjälä <ville.syrjala@linux.intel.com>
>
> Use kHz units in vlv cdclk code since that's more customary.
>
> Also replace the precomputed 90% values with *9/10 computation
> for extra clarity.
>
> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
> ---
> drivers/gpu/drm/i915/intel_display.c | 27 ++++++++++++++-------------
> drivers/gpu/drm/i915/intel_i2c.c | 2 +-
> drivers/gpu/drm/i915/intel_pm.c | 2 +-
> 3 files changed, 16 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
> index 5762726..5f66dc8 100644
> --- a/drivers/gpu/drm/i915/intel_display.c
> +++ b/drivers/gpu/drm/i915/intel_display.c
> @@ -4429,6 +4429,7 @@ static void modeset_update_crtc_power_domains(struct drm_device *dev)
> intel_display_set_init_power(dev_priv, false);
> }
>
> +/* returns HPLL frequency in kHz */
> int valleyview_get_vco(struct drm_i915_private *dev_priv)
> {
> int hpll_freq, vco_freq[] = { 800, 1600, 2000, 2400 };
> @@ -4439,7 +4440,7 @@ int valleyview_get_vco(struct drm_i915_private *dev_priv)
> CCK_FUSE_HPLL_FREQ_MASK;
> mutex_unlock(&dev_priv->dpio_lock);
>
> - return vco_freq[hpll_freq];
> + return vco_freq[hpll_freq] * 1000;
> }
>
> /* Adjust CDclk dividers to allow high res or save power if possible */
> @@ -4451,9 +4452,9 @@ static void valleyview_set_cdclk(struct drm_device *dev, int cdclk)
> WARN_ON(valleyview_cur_cdclk(dev_priv) != dev_priv->vlv_cdclk_freq);
> dev_priv->vlv_cdclk_freq = cdclk;
>
> - if (cdclk >= 320) /* jump to highest voltage for 400MHz too */
> + if (cdclk >= 320000) /* jump to highest voltage for 400MHz too */
> cmd = 2;
> - else if (cdclk == 266)
> + else if (cdclk == 266667)
> cmd = 1;
> else
> cmd = 0;
> @@ -4470,11 +4471,11 @@ static void valleyview_set_cdclk(struct drm_device *dev, int cdclk)
> }
> mutex_unlock(&dev_priv->rps.hw_lock);
>
> - if (cdclk == 400) {
> + if (cdclk == 400000) {
> u32 divider, vco;
>
> vco = valleyview_get_vco(dev_priv);
> - divider = ((vco << 1) / cdclk) - 1;
> + divider = DIV_ROUND_CLOSEST(vco << 1, cdclk) - 1;
>
> mutex_lock(&dev_priv->dpio_lock);
> /* adjust cdclk divider */
> @@ -4494,7 +4495,7 @@ static void valleyview_set_cdclk(struct drm_device *dev, int cdclk)
> * For high bandwidth configs, we set a higher latency in the bunit
> * so that the core display fetch happens in time to avoid underruns.
> */
> - if (cdclk == 400)
> + if (cdclk == 400000)
> val |= 4500 / 250; /* 4.5 usec */
> else
> val |= 3000 / 250; /* 3.0 usec */
> @@ -4518,7 +4519,7 @@ int valleyview_cur_cdclk(struct drm_i915_private *dev_priv)
>
> divider &= 0xf;
>
> - cur_cdclk = (vco << 1) / (divider + 1);
> + cur_cdclk = DIV_ROUND_CLOSEST(vco << 1, divider + 1);
>
> return cur_cdclk;
> }
> @@ -4535,12 +4536,12 @@ static int valleyview_calc_cdclk(struct drm_i915_private *dev_priv,
> * So we check to see whether we're above 90% of the lower bin and
> * adjust if needed.
> */
> - if (max_pixclk > 288000) {
> - return 400;
> - } else if (max_pixclk > 240000) {
> - return 320;
> - } else
> - return 266;
> + if (max_pixclk > 320000*9/10)
> + return 400000;
> + else if (max_pixclk > 266667*9/10)
> + return 320000;
> + else
> + return 266667;
> /* Looks like the 200MHz CDclk freq doesn't work on some configs */
> }
>
> diff --git a/drivers/gpu/drm/i915/intel_i2c.c b/drivers/gpu/drm/i915/intel_i2c.c
> index d33b61d..9ce4f09 100644
> --- a/drivers/gpu/drm/i915/intel_i2c.c
> +++ b/drivers/gpu/drm/i915/intel_i2c.c
> @@ -86,7 +86,7 @@ static void gmbus_set_freq(struct drm_i915_private *dev_priv)
>
> BUG_ON(!IS_VALLEYVIEW(dev_priv->dev));
>
> - vco = valleyview_get_vco(dev_priv);
> + vco = valleyview_get_vco(dev_priv) / 1000;
>
> /* Get the CDCLK divide ratio */
> cdclk_div = get_disp_clk_div(dev_priv, CDCLK);
> diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
> index 5024bc8..a9ddf74 100644
> --- a/drivers/gpu/drm/i915/intel_pm.c
> +++ b/drivers/gpu/drm/i915/intel_pm.c
> @@ -5536,7 +5536,7 @@ static void valleyview_init_clock_gating(struct drm_device *dev)
> DRM_DEBUG_DRIVER("DDR speed: %d MHz", dev_priv->mem_freq);
>
> dev_priv->vlv_cdclk_freq = valleyview_cur_cdclk(dev_priv);
> - DRM_DEBUG_DRIVER("Current CD clock rate: %d MHz",
> + DRM_DEBUG_DRIVER("Current CD clock rate: %d kHz",
> dev_priv->vlv_cdclk_freq);
>
> I915_WRITE(DSPCLK_GATE_D, VRHUNIT_CLOCK_GATE_DISABLE);

Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>

--
Jesse Barnes, Intel Open Source Technology Center