[PATCH 5/8] drm/i915: Add mdclk_cdclk_ratio to intel_dbuf_state

Matt Roper matthew.d.roper at intel.com
Mon Mar 4 23:25:31 UTC 2024


On Mon, Mar 04, 2024 at 03:30:24PM -0300, Gustavo Sousa wrote:
> CDCLK programming Xe2LPD always selects the CDCLK PLL as source for the

I think something got a bit muddled while rewriting this sentence.
Maybe the first two words were supposed to be dropped?

Otherwise,

Reviewed-by: Matt Roper <matthew.d.roper at intel.com>

> MDCLK. Because of that, the ratio between MDCLK and CDCLK is not be
> constant anymore. As such, make sure to have the current ratio available
> in intel_dbuf_state so that it can be used during dbuf programming.
> 
> Note that we write-lock the global state instead of serializing to a
> hardware commit because a change in the ratio should be rather handled
> in the CDCLK change sequence, which will need to take care of updating
> the necessary registers in that case. We will implement that in upcoming
> changes.
> 
> That said, changes in the MBus joining state should be handled by the
> DBUF/MBUS logic, just like it is already done, but the logic will need
> to know the ratio to properly update the registers.
> 
> Signed-off-by: Gustavo Sousa <gustavo.sousa at intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_cdclk.c   | 26 ++++++++++++++++++++
>  drivers/gpu/drm/i915/display/intel_cdclk.h   |  2 ++
>  drivers/gpu/drm/i915/display/skl_watermark.c | 18 +++++++++++++-
>  drivers/gpu/drm/i915/display/skl_watermark.h |  3 +++
>  4 files changed, 48 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_cdclk.c b/drivers/gpu/drm/i915/display/intel_cdclk.c
> index cdf3ae766f9e..04a6e9806254 100644
> --- a/drivers/gpu/drm/i915/display/intel_cdclk.c
> +++ b/drivers/gpu/drm/i915/display/intel_cdclk.c
> @@ -39,6 +39,7 @@
>  #include "intel_pcode.h"
>  #include "intel_psr.h"
>  #include "intel_vdsc.h"
> +#include "skl_watermark.h"
>  #include "vlv_sideband.h"
>  
>  /**
> @@ -1891,6 +1892,22 @@ static u32 xe2lpd_mdclk_source_sel(struct drm_i915_private *i915)
>  	return MDCLK_SOURCE_SEL_CD2XCLK;
>  }
>  
> +u8 intel_mdclk_cdclk_ratio(struct drm_i915_private *i915,
> +			   const struct intel_cdclk_config *cdclk_config)
> +{
> +	u32 source_sel = xe2lpd_mdclk_source_sel(i915);
> +
> +	switch (source_sel) {
> +	case MDCLK_SOURCE_SEL_CD2XCLK:
> +		return 2;
> +	case MDCLK_SOURCE_SEL_CDCLK_PLL:
> +		return DIV_ROUND_UP(cdclk_config->vco, cdclk_config->cdclk);
> +	default:
> +		MISSING_CASE(source_sel);
> +		return 2;
> +	}
> +}
> +
>  static bool cdclk_compute_crawl_and_squash_midpoint(struct drm_i915_private *i915,
>  						    const struct intel_cdclk_config *old_cdclk_config,
>  						    const struct intel_cdclk_config *new_cdclk_config,
> @@ -3281,6 +3298,15 @@ int intel_modeset_calc_cdclk(struct intel_atomic_state *state)
>  			    "Modeset required for cdclk change\n");
>  	}
>  
> +	if (intel_mdclk_cdclk_ratio(dev_priv, &old_cdclk_state->actual) !=
> +	    intel_mdclk_cdclk_ratio(dev_priv, &new_cdclk_state->actual)) {
> +		u8 ratio = intel_mdclk_cdclk_ratio(dev_priv, &new_cdclk_state->actual);
> +
> +		ret = intel_dbuf_state_set_mdclk_cdclk_ratio(state, ratio);
> +		if (ret)
> +			return ret;
> +	}
> +
>  	drm_dbg_kms(&dev_priv->drm,
>  		    "New cdclk calculated to be logical %u kHz, actual %u kHz\n",
>  		    new_cdclk_state->logical.cdclk,
> diff --git a/drivers/gpu/drm/i915/display/intel_cdclk.h b/drivers/gpu/drm/i915/display/intel_cdclk.h
> index fa301495e7f1..8e6e302bd599 100644
> --- a/drivers/gpu/drm/i915/display/intel_cdclk.h
> +++ b/drivers/gpu/drm/i915/display/intel_cdclk.h
> @@ -62,6 +62,8 @@ void intel_update_cdclk(struct drm_i915_private *dev_priv);
>  u32 intel_read_rawclk(struct drm_i915_private *dev_priv);
>  bool intel_cdclk_clock_changed(const struct intel_cdclk_config *a,
>  			       const struct intel_cdclk_config *b);
> +u8 intel_mdclk_cdclk_ratio(struct drm_i915_private *i915,
> +			   const struct intel_cdclk_config *cdclk_config);
>  void intel_set_cdclk_pre_plane_update(struct intel_atomic_state *state);
>  void intel_set_cdclk_post_plane_update(struct intel_atomic_state *state);
>  void intel_cdclk_dump_config(struct drm_i915_private *i915,
> diff --git a/drivers/gpu/drm/i915/display/skl_watermark.c b/drivers/gpu/drm/i915/display/skl_watermark.c
> index d9e49cd60d3a..4410e21888ad 100644
> --- a/drivers/gpu/drm/i915/display/skl_watermark.c
> +++ b/drivers/gpu/drm/i915/display/skl_watermark.c
> @@ -3057,6 +3057,8 @@ static void skl_wm_get_hw_state(struct drm_i915_private *i915)
>  	if (HAS_MBUS_JOINING(i915))
>  		dbuf_state->joined_mbus = intel_de_read(i915, MBUS_CTL) & MBUS_JOIN;
>  
> +	dbuf_state->mdclk_cdclk_ratio = intel_mdclk_cdclk_ratio(i915, &i915->display.cdclk.hw);
> +
>  	for_each_intel_crtc(&i915->drm, crtc) {
>  		struct intel_crtc_state *crtc_state =
>  			to_intel_crtc_state(crtc->base.state);
> @@ -3530,6 +3532,19 @@ int intel_dbuf_init(struct drm_i915_private *i915)
>  	return 0;
>  }
>  
> +int intel_dbuf_state_set_mdclk_cdclk_ratio(struct intel_atomic_state *state, u8 ratio)
> +{
> +	struct intel_dbuf_state *dbuf_state;
> +
> +	dbuf_state = intel_atomic_get_dbuf_state(state);
> +	if (IS_ERR(dbuf_state))
> +		return PTR_ERR(dbuf_state);
> +
> +	dbuf_state->mdclk_cdclk_ratio = ratio;
> +
> +	return intel_atomic_lock_global_state(&dbuf_state->base);
> +}
> +
>  static void intel_dbuf_mdclk_cdclk_ratio_update(struct drm_i915_private *i915,
>  						u8 ratio,
>  						bool joined_mbus)
> @@ -3574,7 +3589,8 @@ static void update_mbus_pre_enable(struct intel_atomic_state *state)
>  		     MBUS_HASHING_MODE_MASK | MBUS_JOIN |
>  		     MBUS_JOIN_PIPE_SELECT_MASK, mbus_ctl);
>  
> -	intel_dbuf_mdclk_cdclk_ratio_update(i915, 2, dbuf_state->joined_mbus);
> +	intel_dbuf_mdclk_cdclk_ratio_update(i915, dbuf_state->mdclk_cdclk_ratio,
> +					    dbuf_state->joined_mbus);
>  }
>  
>  void intel_dbuf_pre_plane_update(struct intel_atomic_state *state)
> diff --git a/drivers/gpu/drm/i915/display/skl_watermark.h b/drivers/gpu/drm/i915/display/skl_watermark.h
> index e3d1d74a7b17..fed4d12df584 100644
> --- a/drivers/gpu/drm/i915/display/skl_watermark.h
> +++ b/drivers/gpu/drm/i915/display/skl_watermark.h
> @@ -58,6 +58,7 @@ struct intel_dbuf_state {
>  	u8 slices[I915_MAX_PIPES];
>  	u8 enabled_slices;
>  	u8 active_pipes;
> +	u8 mdclk_cdclk_ratio;
>  	bool joined_mbus;
>  };
>  
> @@ -71,6 +72,8 @@ intel_atomic_get_dbuf_state(struct intel_atomic_state *state);
>  	to_intel_dbuf_state(intel_atomic_get_new_global_obj_state(state, &to_i915(state->base.dev)->display.dbuf.obj))
>  
>  int intel_dbuf_init(struct drm_i915_private *i915);
> +int intel_dbuf_state_set_mdclk_cdclk_ratio(struct intel_atomic_state *state, u8 ratio);
> +
>  void intel_dbuf_pre_plane_update(struct intel_atomic_state *state);
>  void intel_dbuf_post_plane_update(struct intel_atomic_state *state);
>  void intel_mbus_dbox_update(struct intel_atomic_state *state);
> -- 
> 2.44.0
> 

-- 
Matt Roper
Graphics Software Engineer
Linux GPU Platform Enablement
Intel Corporation


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