Re: [PATCH v5 1/2] drm/i915: Disable/Enable PM Intrrupts based on the current freq.

["Ville Syrjälä" <ville.syrjala@linux.intel.com>]

On Mon, Jan 27, 2014 at 09:35:05PM +0530, deepak.s@intel.com wrote:
> From: Deepak S <deepak.s@intel.com>
> 
> When current delay is already at max delay, Let's disable the PM UP
> THRESHOLD INTRRUPTS, so that we will not get further interrupts until
> current delay is less than max delay, Also request for the PM DOWN
> THRESHOLD INTRRUPTS to indicate the decrease in clock freq. and
> viceversa for PM DOWN THRESHOLD INTRRUPTS.
> 
> v2: Use bool variables (Daniel)
> 
> v3: Fix Interrupt masking bit (Deepak)
> 
> v4: Use existing symbolic constants in i915_reg.h (Daniel)
> 
> v5: Add pm interrupt mask after new_delay calculation (Ville)
> 
> Signed-off-by: Deepak S <deepak.s@intel.com>
> ---
>  drivers/gpu/drm/i915/i915_drv.h |  3 +++
>  drivers/gpu/drm/i915/i915_irq.c | 39 +++++++++++++++++++++++++++++++++++++++
>  drivers/gpu/drm/i915/intel_pm.c |  3 +++
>  3 files changed, 45 insertions(+)
> 
> diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
> index 56c720b..f19de66 100644
> --- a/drivers/gpu/drm/i915/i915_drv.h
> +++ b/drivers/gpu/drm/i915/i915_drv.h
> @@ -943,6 +943,9 @@ struct intel_gen6_power_mgmt {
>  	u8 rp0_delay;
>  	u8 hw_max;
>  
> +	bool rp_up_masked;
> +	bool rp_down_masked;
> +
>  	int last_adj;
>  	enum { LOW_POWER, BETWEEN, HIGH_POWER } power;
>  
> diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
> index 01a8686..69a5214 100644
> --- a/drivers/gpu/drm/i915/i915_irq.c
> +++ b/drivers/gpu/drm/i915/i915_irq.c
> @@ -972,6 +972,43 @@ static void notify_ring(struct drm_device *dev,
>  	i915_queue_hangcheck(dev);
>  }
>  
> +static void gen6_set_pm_mask(struct drm_i915_private *dev_priv,
> +						u32 pm_iir, int *new_delay)

Just a minor nit here. We don't modify new_delay in this function, so
passing by value would be better.

Otherwise the patch looks good to me. So if you change that, you can
add:
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

> +{
> +	if (pm_iir & GEN6_PM_RP_UP_THRESHOLD) {
> +		if (*new_delay >= dev_priv->rps.max_delay) {
> +			/* Mask UP THRESHOLD Interrupts */
> +			I915_WRITE(GEN6_PMINTRMSK,
> +				I915_READ(GEN6_PMINTRMSK) |
> +						GEN6_PM_RP_UP_THRESHOLD);
> +			dev_priv->rps.rp_up_masked = true;
> +		}
> +		if (dev_priv->rps.rp_down_masked) {
> +			/* UnMask DOWN THRESHOLD Interrupts */
> +			I915_WRITE(GEN6_PMINTRMSK,
> +				I915_READ(GEN6_PMINTRMSK) &
> +						~GEN6_PM_RP_DOWN_THRESHOLD);
> +			dev_priv->rps.rp_down_masked = false;
> +		}
> +	} else if (pm_iir & GEN6_PM_RP_DOWN_THRESHOLD) {
> +		if (*new_delay <= dev_priv->rps.min_delay) {
> +			/* Mask DOWN THRESHOLD Interrupts */
> +			I915_WRITE(GEN6_PMINTRMSK,
> +					I915_READ(GEN6_PMINTRMSK) |
> +						GEN6_PM_RP_DOWN_THRESHOLD);
> +			dev_priv->rps.rp_down_masked = true;
> +		}
> +
> +		if (dev_priv->rps.rp_up_masked) {
> +			/* UnMask UP THRESHOLD Interrupts */
> +			I915_WRITE(GEN6_PMINTRMSK,
> +				I915_READ(GEN6_PMINTRMSK) &
> +						~GEN6_PM_RP_UP_THRESHOLD);
> +			dev_priv->rps.rp_up_masked = false;
> +		}
> +	}
> +}
> +
>  static void gen6_pm_rps_work(struct work_struct *work)
>  {
>  	drm_i915_private_t *dev_priv = container_of(work, drm_i915_private_t,
> @@ -1029,6 +1066,8 @@ static void gen6_pm_rps_work(struct work_struct *work)
>  	 */
>  	new_delay = clamp_t(int, new_delay,
>  			    dev_priv->rps.min_delay, dev_priv->rps.max_delay);
> +
> +	gen6_set_pm_mask(dev_priv, pm_iir, &new_delay);
>  	dev_priv->rps.last_adj = new_delay - dev_priv->rps.cur_delay;
>  
>  	if (IS_VALLEYVIEW(dev_priv->dev))
> diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
> index b9b4fe4..c6a07c9 100644
> --- a/drivers/gpu/drm/i915/intel_pm.c
> +++ b/drivers/gpu/drm/i915/intel_pm.c
> @@ -3615,6 +3615,9 @@ static void valleyview_enable_rps(struct drm_device *dev)
>  
>  	valleyview_set_rps(dev_priv->dev, dev_priv->rps.rpe_delay);
>  
> +	dev_priv->rps.rp_up_masked = false;
> +	dev_priv->rps.rp_down_masked = false;
> +
>  	gen6_enable_rps_interrupts(dev);
>  
>  	gen6_gt_force_wake_put(dev_priv, FORCEWAKE_ALL);
> -- 
> 1.8.5.2
> 
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx@lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/intel-gfx

-- 
Ville Syrjälä
Intel OTC