Re: [PATCH 02/12] drm/i915/ddi: Move all mso related helpers to a new file

[Jani Nikula <jani.nikula@linux.intel.com>]

On Mon, 26 Aug 2024, Ankit Nautiyal <ankit.k.nautiyal@intel.com> wrote:
> Move the MSO related helper functions from intel_ddi.c to a new file
> intel_dss.c to improve code modularity and maintainability.
> The corresponding headers are also moved to intel_dss.h.
>
> Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
> ---
>  drivers/gpu/drm/i915/Makefile            |  1 +
>  drivers/gpu/drm/i915/display/intel_ddi.c | 86 ++---------------------
>  drivers/gpu/drm/i915/display/intel_dss.c | 87 ++++++++++++++++++++++++
>  drivers/gpu/drm/i915/display/intel_dss.h | 21 ++++++
>  drivers/gpu/drm/xe/Makefile              |  1 +
>  5 files changed, 115 insertions(+), 81 deletions(-)
>  create mode 100644 drivers/gpu/drm/i915/display/intel_dss.c
>  create mode 100644 drivers/gpu/drm/i915/display/intel_dss.h
>
> diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile
> index c63fa2133ccb..e55ce8ba123c 100644
> --- a/drivers/gpu/drm/i915/Makefile
> +++ b/drivers/gpu/drm/i915/Makefile
> @@ -328,6 +328,7 @@ i915-y += \
>  	display/intel_dsi.o \
>  	display/intel_dsi_dcs_backlight.o \
>  	display/intel_dsi_vbt.o \
> +	display/intel_dss.o \
>  	display/intel_dvo.o \
>  	display/intel_encoder.o \
>  	display/intel_gmbus.o \
> diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/i915/display/intel_ddi.c
> index 4566a60c981c..28ef6814c56c 100644
> --- a/drivers/gpu/drm/i915/display/intel_ddi.c
> +++ b/drivers/gpu/drm/i915/display/intel_ddi.c
> @@ -57,7 +57,7 @@
>  #include "intel_dp_tunnel.h"
>  #include "intel_dpio_phy.h"
>  #include "intel_dsi.h"
> -#include "intel_dss_regs.h"
> +#include "intel_dss.h"
>  #include "intel_encoder.h"
>  #include "intel_fdi.h"
>  #include "intel_fifo_underrun.h"
> @@ -2349,82 +2349,6 @@ static void intel_ddi_power_up_lanes(struct intel_encoder *encoder,
>  	}
>  }
>  
> -/*
> - * Splitter enable for eDP MSO is limited to certain pipes, on certain
> - * platforms.
> - */
> -static u8 intel_ddi_splitter_pipe_mask(struct drm_i915_private *i915)
> -{
> -	if (DISPLAY_VER(i915) > 20)
> -		return ~0;
> -	else if (IS_ALDERLAKE_P(i915))
> -		return BIT(PIPE_A) | BIT(PIPE_B);
> -	else
> -		return BIT(PIPE_A);
> -}
> -
> -static void intel_ddi_mso_get_config(struct intel_encoder *encoder,
> -				     struct intel_crtc_state *pipe_config)
> -{
> -	struct intel_crtc *crtc = to_intel_crtc(pipe_config->uapi.crtc);
> -	struct drm_i915_private *i915 = to_i915(crtc->base.dev);
> -	enum pipe pipe = crtc->pipe;
> -	u32 dss1;
> -
> -	if (!HAS_MSO(i915))
> -		return;
> -
> -	dss1 = intel_de_read(i915, ICL_PIPE_DSS_CTL1(pipe));
> -
> -	pipe_config->splitter.enable = dss1 & SPLITTER_ENABLE;
> -	if (!pipe_config->splitter.enable)
> -		return;
> -
> -	if (drm_WARN_ON(&i915->drm, !(intel_ddi_splitter_pipe_mask(i915) & BIT(pipe)))) {
> -		pipe_config->splitter.enable = false;
> -		return;
> -	}
> -
> -	switch (dss1 & SPLITTER_CONFIGURATION_MASK) {
> -	default:
> -		drm_WARN(&i915->drm, true,
> -			 "Invalid splitter configuration, dss1=0x%08x\n", dss1);
> -		fallthrough;
> -	case SPLITTER_CONFIGURATION_2_SEGMENT:
> -		pipe_config->splitter.link_count = 2;
> -		break;
> -	case SPLITTER_CONFIGURATION_4_SEGMENT:
> -		pipe_config->splitter.link_count = 4;
> -		break;
> -	}
> -
> -	pipe_config->splitter.pixel_overlap = REG_FIELD_GET(OVERLAP_PIXELS_MASK, dss1);
> -}
> -
> -static void intel_ddi_mso_configure(const struct intel_crtc_state *crtc_state)
> -{
> -	struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
> -	struct drm_i915_private *i915 = to_i915(crtc->base.dev);
> -	enum pipe pipe = crtc->pipe;
> -	u32 dss1 = 0;
> -
> -	if (!HAS_MSO(i915))
> -		return;
> -
> -	if (crtc_state->splitter.enable) {
> -		dss1 |= SPLITTER_ENABLE;
> -		dss1 |= OVERLAP_PIXELS(crtc_state->splitter.pixel_overlap);
> -		if (crtc_state->splitter.link_count == 2)
> -			dss1 |= SPLITTER_CONFIGURATION_2_SEGMENT;
> -		else
> -			dss1 |= SPLITTER_CONFIGURATION_4_SEGMENT;
> -	}
> -
> -	intel_de_rmw(i915, ICL_PIPE_DSS_CTL1(pipe),
> -		     SPLITTER_ENABLE | SPLITTER_CONFIGURATION_MASK |
> -		     OVERLAP_PIXELS_MASK, dss1);
> -}
> -
>  static u8 mtl_get_port_width(u8 lane_count)
>  {
>  	switch (lane_count) {
> @@ -2559,7 +2483,7 @@ static void mtl_ddi_pre_enable_dp(struct intel_atomic_state *state,
>  	/*
>  	 * 6.e Program CoG/MSO configuration bits in DSS_CTL1 if selected.
>  	 */
> -	intel_ddi_mso_configure(crtc_state);
> +	intel_dss_configure_mso(crtc_state);
>  
>  	if (!is_mst)
>  		intel_dp_set_power(intel_dp, DP_SET_POWER_D0);
> @@ -2714,7 +2638,7 @@ static void tgl_ddi_pre_enable_dp(struct intel_atomic_state *state,
>  	/*
>  	 * 7.g Program CoG/MSO configuration bits in DSS_CTL1 if selected.
>  	 */
> -	intel_ddi_mso_configure(crtc_state);
> +	intel_dss_configure_mso(crtc_state);
>  
>  	if (!is_mst)
>  		intel_dp_set_power(intel_dp, DP_SET_POWER_D0);
> @@ -3959,7 +3883,7 @@ static void intel_ddi_get_config(struct intel_encoder *encoder,
>  
>  	intel_ddi_read_func_ctl(encoder, pipe_config);
>  
> -	intel_ddi_mso_get_config(encoder, pipe_config);
> +	intel_dss_get_mso_config(encoder, pipe_config);
>  
>  	pipe_config->has_audio =
>  		intel_ddi_is_audio_enabled(dev_priv, cpu_transcoder);
> @@ -5191,7 +5115,7 @@ void intel_ddi_init(struct intel_display *display,
>  		dig_port->hpd_pulse = intel_dp_hpd_pulse;
>  
>  		if (dig_port->dp.mso_link_count)
> -			encoder->pipe_mask = intel_ddi_splitter_pipe_mask(dev_priv);
> +			encoder->pipe_mask = intel_dss_splitter_pipe_mask(dev_priv);
>  	}
>  
>  	/*
> diff --git a/drivers/gpu/drm/i915/display/intel_dss.c b/drivers/gpu/drm/i915/display/intel_dss.c
> new file mode 100644
> index 000000000000..41ea42d234f9
> --- /dev/null
> +++ b/drivers/gpu/drm/i915/display/intel_dss.c
> @@ -0,0 +1,87 @@
> +// SPDX-License-Identifier: MIT
> +/*
> + * Copyright © 2024 Intel Corporation
> + */
> +
> +#include "i915_drv.h"
> +#include "i915_reg_defs.h"
> +#include "intel_de.h"
> +#include "intel_display_types.h"
> +#include "intel_dss.h"
> +#include "intel_dss_regs.h"
> +
> +/*
> + * Splitter enable for eDP MSO is limited to certain pipes, on certain
> + * platforms.
> + */
> +u8 intel_dss_splitter_pipe_mask(struct drm_i915_private *i915)
> +{
> +	if (DISPLAY_VER(i915) > 20)
> +		return ~0;
> +	else if (IS_ALDERLAKE_P(i915))
> +		return BIT(PIPE_A) | BIT(PIPE_B);
> +	else
> +		return BIT(PIPE_A);
> +}
> +
> +void intel_dss_get_mso_config(struct intel_encoder *encoder,
> +			      struct intel_crtc_state *pipe_config)
> +{
> +	struct intel_crtc *crtc = to_intel_crtc(pipe_config->uapi.crtc);
> +	struct drm_i915_private *i915 = to_i915(crtc->base.dev);
> +	enum pipe pipe = crtc->pipe;
> +	u32 dss1;
> +
> +	if (!HAS_MSO(i915))
> +		return;
> +
> +	dss1 = intel_de_read(i915, ICL_PIPE_DSS_CTL1(pipe));
> +
> +	pipe_config->splitter.enable = dss1 & SPLITTER_ENABLE;
> +	if (!pipe_config->splitter.enable)
> +		return;
> +
> +	if (drm_WARN_ON(&i915->drm, !(intel_dss_splitter_pipe_mask(i915) & BIT(pipe)))) {
> +		pipe_config->splitter.enable = false;
> +		return;
> +	}
> +
> +	switch (dss1 & SPLITTER_CONFIGURATION_MASK) {
> +	default:
> +		drm_WARN(&i915->drm, true,
> +			 "Invalid splitter configuration, dss1=0x%08x\n", dss1);
> +		fallthrough;
> +	case SPLITTER_CONFIGURATION_2_SEGMENT:
> +		pipe_config->splitter.link_count = 2;
> +		break;
> +	case SPLITTER_CONFIGURATION_4_SEGMENT:
> +		pipe_config->splitter.link_count = 4;
> +		break;
> +	}
> +
> +	pipe_config->splitter.pixel_overlap = REG_FIELD_GET(OVERLAP_PIXELS_MASK, dss1);
> +}
> +
> +void intel_dss_configure_mso(const struct intel_crtc_state *crtc_state)
> +{
> +	struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
> +	struct drm_i915_private *i915 = to_i915(crtc->base.dev);
> +	enum pipe pipe = crtc->pipe;
> +	u32 dss1 = 0;
> +
> +	if (!HAS_MSO(i915))
> +		return;
> +
> +	if (crtc_state->splitter.enable) {
> +		dss1 |= SPLITTER_ENABLE;
> +		dss1 |= OVERLAP_PIXELS(crtc_state->splitter.pixel_overlap);
> +		if (crtc_state->splitter.link_count == 2)
> +			dss1 |= SPLITTER_CONFIGURATION_2_SEGMENT;
> +		else
> +			dss1 |= SPLITTER_CONFIGURATION_4_SEGMENT;
> +	}
> +
> +	intel_de_rmw(i915, ICL_PIPE_DSS_CTL1(pipe),
> +		     SPLITTER_ENABLE | SPLITTER_CONFIGURATION_MASK |
> +		     OVERLAP_PIXELS_MASK, dss1);
> +}
> diff --git a/drivers/gpu/drm/i915/display/intel_dss.h b/drivers/gpu/drm/i915/display/intel_dss.h
> new file mode 100644
> index 000000000000..632a00f0ebc1
> --- /dev/null
> +++ b/drivers/gpu/drm/i915/display/intel_dss.h
> @@ -0,0 +1,21 @@
> +/* SPDX-License-Identifier: MIT */
> +/*
> + * Copyright © 2024 Intel Corporation
> + */
> +
> +#ifndef __INTEL_DSS_H__
> +#define __INTEL_DSS_H__
> +
> +#include "linux/types.h"
> +
> +struct drm_i915_private;
> +struct intel_crtc_state;
> +struct intel_encoder;
> +
> +u8 intel_dss_splitter_pipe_mask(struct drm_i915_private *i915);
> +void intel_dss_get_mso_config(struct intel_encoder *encoder,
> +			      struct intel_crtc_state *pipe_config);
> +void intel_dss_configure_mso(const struct intel_crtc_state *crtc_state);

Nitpick, I'd probably name all of these intel_dss_mso_*.

intel_dss_mso_pipe_mask
intel_dss_mso_get_config
intel_dss_mso_configure

Especially "_get_config" suffix is a naming pattern for functions called
on the encoder->get_config path, and you don't want to add words in
between.

BR,
Jani.


> +
> +#endif /* __INTEL_DSS_H__ */
> +
> diff --git a/drivers/gpu/drm/xe/Makefile b/drivers/gpu/drm/xe/Makefile
> index b9670ae09a9e..619272783669 100644
> --- a/drivers/gpu/drm/xe/Makefile
> +++ b/drivers/gpu/drm/xe/Makefile
> @@ -227,6 +227,7 @@ xe-$(CONFIG_DRM_XE_DISPLAY) += \
>  	i915-display/intel_dsi.o \
>  	i915-display/intel_dsi_dcs_backlight.o \
>  	i915-display/intel_dsi_vbt.o \
> +	i915-display/intel_dss.o \
>  	i915-display/intel_encoder.o \
>  	i915-display/intel_fb.o \
>  	i915-display/intel_fbc.o \

-- 
Jani Nikula, Intel