Re: [PATCH] drm/i915: Remove unused underrun interrupt bits

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

On Wed, Sep 25, 2024 at 04:48:02PM +0530, Sai Teja Pottumuttu wrote:
> Underrun recovery was defeatured and was never brought into usage.
> Thus we can safely remove the interrupt register bits introduced by the
> feature for detecting soft and hard underruns.
> 
> Signed-off-by: Sai Teja Pottumuttu <sai.teja.pottumuttu@intel.com>
> ---
>  .../gpu/drm/i915/display/intel_display_irq.c  | 19 +++----------------
>  .../gpu/drm/i915/display/intel_display_irq.h  |  1 -
>  .../drm/i915/display/intel_fifo_underrun.c    |  5 ++---

There's a lot more related stuff in that file.

>  drivers/gpu/drm/i915/i915_reg.h               |  2 --
>  4 files changed, 5 insertions(+), 22 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_display_irq.c b/drivers/gpu/drm/i915/display/intel_display_irq.c
> index 6878dde85031..9d8a101b2415 100644
> --- a/drivers/gpu/drm/i915/display/intel_display_irq.c
> +++ b/drivers/gpu/drm/i915/display/intel_display_irq.c
> @@ -1031,17 +1031,6 @@ static u32 gen8_de_pipe_flip_done_mask(struct drm_i915_private *i915)
>  		return GEN8_PIPE_PRIMARY_FLIP_DONE;
>  }
>  
> -u32 gen8_de_pipe_underrun_mask(struct drm_i915_private *dev_priv)
> -{
> -	u32 mask = GEN8_PIPE_FIFO_UNDERRUN;
> -
> -	if (DISPLAY_VER(dev_priv) >= 13)
> -		mask |= XELPD_PIPE_SOFT_UNDERRUN |
> -			XELPD_PIPE_HARD_UNDERRUN;
> -
> -	return mask;
> -}
> -
>  static void gen8_read_and_ack_pch_irqs(struct drm_i915_private *i915, u32 *pch_iir, u32 *pica_iir)
>  {
>  	u32 pica_ier = 0;
> @@ -1187,7 +1176,7 @@ void gen8_de_irq_handler(struct drm_i915_private *dev_priv, u32 master_ctl)
>  		if (iir & GEN8_PIPE_CDCLK_CRC_DONE)
>  			hsw_pipe_crc_irq_handler(dev_priv, pipe);
>  
> -		if (iir & gen8_de_pipe_underrun_mask(dev_priv))
> +		if (iir & GEN8_PIPE_FIFO_UNDERRUN)
>  			intel_cpu_fifo_underrun_irq_handler(dev_priv, pipe);
>  
>  		fault_errors = iir & gen8_de_pipe_fault_mask(dev_priv);
> @@ -1607,8 +1596,7 @@ void gen8_irq_power_well_post_enable(struct drm_i915_private *dev_priv,
>  				     u8 pipe_mask)
>  {
>  	struct intel_uncore *uncore = &dev_priv->uncore;
> -	u32 extra_ier = GEN8_PIPE_VBLANK |
> -		gen8_de_pipe_underrun_mask(dev_priv) |
> +	u32 extra_ier = GEN8_PIPE_VBLANK | GEN8_PIPE_FIFO_UNDERRUN |
>  		gen8_de_pipe_flip_done_mask(dev_priv);
>  	enum pipe pipe;
>  
> @@ -1797,8 +1785,7 @@ void gen8_de_irq_postinstall(struct drm_i915_private *dev_priv)
>  			GEN12_DSB_INT(INTEL_DSB_2);
>  
>  	de_pipe_enables = de_pipe_masked |
> -		GEN8_PIPE_VBLANK |
> -		gen8_de_pipe_underrun_mask(dev_priv) |
> +		GEN8_PIPE_VBLANK | GEN8_PIPE_FIFO_UNDERRUN |
>  		gen8_de_pipe_flip_done_mask(dev_priv);
>  
>  	de_port_enables = de_port_masked;
> diff --git a/drivers/gpu/drm/i915/display/intel_display_irq.h b/drivers/gpu/drm/i915/display/intel_display_irq.h
> index 093e356a2894..1b3f559a0638 100644
> --- a/drivers/gpu/drm/i915/display/intel_display_irq.h
> +++ b/drivers/gpu/drm/i915/display/intel_display_irq.h
> @@ -33,7 +33,6 @@ void ibx_disable_display_interrupt(struct drm_i915_private *i915, u32 bits);
>  
>  void gen8_irq_power_well_post_enable(struct drm_i915_private *i915, u8 pipe_mask);
>  void gen8_irq_power_well_pre_disable(struct drm_i915_private *i915, u8 pipe_mask);
> -u32 gen8_de_pipe_underrun_mask(struct drm_i915_private *i915);
>  
>  int i8xx_enable_vblank(struct drm_crtc *crtc);
>  int i915gm_enable_vblank(struct drm_crtc *crtc);
> diff --git a/drivers/gpu/drm/i915/display/intel_fifo_underrun.c b/drivers/gpu/drm/i915/display/intel_fifo_underrun.c
> index 745ce22afb89..fb01c128e1c5 100644
> --- a/drivers/gpu/drm/i915/display/intel_fifo_underrun.c
> +++ b/drivers/gpu/drm/i915/display/intel_fifo_underrun.c
> @@ -209,7 +209,6 @@ static void bdw_set_fifo_underrun_reporting(struct drm_device *dev,
>  					    enum pipe pipe, bool enable)
>  {
>  	struct drm_i915_private *dev_priv = to_i915(dev);
> -	u32 mask = gen8_de_pipe_underrun_mask(dev_priv);
>  
>  	if (enable) {
>  		if (DISPLAY_VER(dev_priv) >= 11)
> @@ -217,9 +216,9 @@ static void bdw_set_fifo_underrun_reporting(struct drm_device *dev,
>  				       ICL_PIPESTATUS(dev_priv, pipe),
>  				       icl_pipe_status_underrun_mask(dev_priv));
>  
> -		bdw_enable_pipe_irq(dev_priv, pipe, mask);
> +		bdw_enable_pipe_irq(dev_priv, pipe, GEN8_PIPE_FIFO_UNDERRUN);
>  	} else {
> -		bdw_disable_pipe_irq(dev_priv, pipe, mask);
> +		bdw_disable_pipe_irq(dev_priv, pipe, GEN8_PIPE_FIFO_UNDERRUN);
>  	}
>  }
>  
> diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
> index 7396fc630e29..c379d875f432 100644
> --- a/drivers/gpu/drm/i915/i915_reg.h
> +++ b/drivers/gpu/drm/i915/i915_reg.h
> @@ -2491,9 +2491,7 @@
>  #define  GEN12_PIPEDMC_INTERRUPT	REG_BIT(26) /* tgl+ */
>  #define  GEN12_PIPEDMC_FAULT		REG_BIT(25) /* tgl+ */
>  #define  MTL_PIPEDMC_ATS_FAULT		REG_BIT(24) /* mtl+ */
> -#define  XELPD_PIPE_SOFT_UNDERRUN	REG_BIT(22) /* adl/dg2+ */
>  #define  GEN11_PIPE_PLANE7_FAULT	REG_BIT(22) /* icl/tgl */
> -#define  XELPD_PIPE_HARD_UNDERRUN	REG_BIT(21) /* adl/dg2+ */
>  #define  GEN11_PIPE_PLANE6_FAULT	REG_BIT(21) /* icl/tgl */
>  #define  GEN11_PIPE_PLANE5_FAULT	REG_BIT(20) /* icl+ */
>  #define  GEN12_PIPE_VBLANK_UNMOD	REG_BIT(19) /* tgl+ */
> -- 
> 2.34.1

-- 
Ville Syrjälä
Intel