Re: [Intel-gfx] [RFC PATCH 1/5] drm/i915/bios: calculate drrs mode using panel index for dual LFP

From: Jani Nikula <jani.nikula@intel.com>
To: Animesh Manna <animesh.manna@intel.com>, intel-gfx@lists.freedesktop.org
Subject: Re: [Intel-gfx] [RFC PATCH 1/5] drm/i915/bios: calculate drrs mode using panel index for dual LFP
Date: Thu, 02 Jun 2022 18:11:11 +0300	[thread overview]
Message-ID: <87fsknp0c0.fsf@intel.com> (raw)
In-Reply-To: <87ilpjp0it.fsf@intel.com>

On Thu, 02 Jun 2022, Jani Nikula <jani.nikula@intel.com> wrote:
> On Thu, 02 Jun 2022, Animesh Manna <animesh.manna@intel.com> wrote:
>> Dual LFP may have different panel and based on panel index
>> respective 2 bits store the drrs mode info for each panel. So panel
>> index is used for deriving drrs mode of the rspective panel.
>>
>> Signed-off-by: Animesh Manna <animesh.manna@intel.com>
>> ---
>>  drivers/gpu/drm/i915/display/icl_dsi.c        |  2 +-
>>  drivers/gpu/drm/i915/display/intel_bios.c     | 45 +++++++++++++++++--
>>  drivers/gpu/drm/i915/display/intel_bios.h     |  3 +-
>>  drivers/gpu/drm/i915/display/intel_dp.c       |  3 +-
>>  drivers/gpu/drm/i915/display/intel_lvds.c     |  3 +-
>>  drivers/gpu/drm/i915/display/intel_sdvo.c     |  2 +-
>>  drivers/gpu/drm/i915/display/intel_vbt_defs.h |  4 ++
>>  drivers/gpu/drm/i915/display/vlv_dsi.c        |  2 +-
>>  8 files changed, 52 insertions(+), 12 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/display/icl_dsi.c b/drivers/gpu/drm/i915/display/icl_dsi.c
>> index 3b5305c219ba..b3aa430abd03 100644
>> --- a/drivers/gpu/drm/i915/display/icl_dsi.c
>> +++ b/drivers/gpu/drm/i915/display/icl_dsi.c
>> @@ -2050,7 +2050,7 @@ void icl_dsi_init(struct drm_i915_private *dev_priv)
>>  	/* attach connector to encoder */
>>  	intel_connector_attach_encoder(intel_connector, encoder);
>>  
>> -	intel_bios_init_panel(dev_priv, &intel_connector->panel, NULL);
>> +	intel_bios_init_panel(dev_priv, intel_connector, NULL);
>>  
>>  	mutex_lock(&dev->mode_config.mutex);
>>  	intel_panel_add_vbt_lfp_fixed_mode(intel_connector);
>> diff --git a/drivers/gpu/drm/i915/display/intel_bios.c b/drivers/gpu/drm/i915/display/intel_bios.c
>> index 337277ae3dae..78eaf6255599 100644
>> --- a/drivers/gpu/drm/i915/display/intel_bios.c
>> +++ b/drivers/gpu/drm/i915/display/intel_bios.c
>> @@ -747,7 +747,8 @@ static int get_panel_type(struct drm_i915_private *i915,
>>  static void
>>  parse_panel_options(struct drm_i915_private *i915,
>>  		    struct intel_panel *panel,
>> -		    const struct edid *edid)
>> +		    const struct edid *edid,
>> +		    int panel_index)
>>  {
>>  	const struct bdb_lvds_options *lvds_options;
>>  	int panel_type;
>> @@ -764,7 +765,7 @@ parse_panel_options(struct drm_i915_private *i915,
>>  	panel->vbt.panel_type = panel_type;
>>  
>>  	drrs_mode = (lvds_options->dps_panel_type_bits
>> -				>> (panel_type * 2)) & MODE_MASK;
>> +				>> (panel_index * 2)) & MODE_MASK;
>
> It's the get_panel_type() call that needs to take the panel number into
> account, and return the panel specific panel_type from there. After
> that, it's stored in panel->vbt.panel_type and it'll be used
> everywere. DRRS is not a special case.
>
>>  	/*
>>  	 * VBT has static DRRS = 0 and seamless DRRS = 2.
>>  	 * The below piece of code is required to adjust vbt.drrs_type
>> @@ -3069,13 +3070,49 @@ void intel_bios_init(struct drm_i915_private *i915)
>>  	kfree(oprom_vbt);
>>  }
>>  
>> +static int
>> +get_lfp_panel_index(struct drm_i915_private *i915, int lfp_panel_instance)
>> +{
>> +	const struct bdb_lvds_options *lvds_options;
>> +
>> +	lvds_options = find_section(i915, BDB_LVDS_OPTIONS);
>> +	if (!lvds_options)
>> +		return -1;
>> +
>> +	switch (lfp_panel_instance) {
>> +	case 1:
>> +		return lvds_options->panel_type;
>> +	case 2:
>> +		return lvds_options->panel_type2;
>> +	default:
>> +		break;
>> +	}
>> +
>> +	return -1;
>> +}
>
> Nah, it's not this simple. See get_panel_type(). Either of the
> panel_type fields could be 0xff to indicate PNPID based lookup.
>
>> +
>>  void intel_bios_init_panel(struct drm_i915_private *i915,
>> -			   struct intel_panel *panel,
>> +			   struct intel_connector *intel_connector,
>>  			   const struct edid *edid)
>>  {
>> +	struct intel_panel *panel = &intel_connector->panel;
>> +	struct intel_encoder *encoder = intel_connector->encoder;
>> +	const struct intel_bios_encoder_data *devdata = i915->vbt.ports[encoder->port];
>
> This might be NULL, we don't initialize ports for all platforms.
>
>
>> +	int lfp_inst = 0, panel_index;
>> +
>>  	init_vbt_panel_defaults(panel);
>>  
>> -	parse_panel_options(i915, panel, edid);
>> +	if (devdata->child.handle == HANDLE_LFP_1)
>> +		lfp_inst = 1;
>> +	else if (devdata->child.handle == HANDLE_LFP_2)
>> +		lfp_inst = 2;
>> +
>> +	if (lfp_inst == 0)
>> +		return;
>> +
>> +	panel_index = get_lfp_panel_index(i915, lfp_inst);
>> +
>> +	parse_panel_options(i915, panel, edid, panel_index);

Also, none of this handling should happen here. Just pass devdata on to
parse_panel_options(), and pass it on further to get_panel_type(), which
should be the single point of truth for figuring out the panel type.

>>  	parse_generic_dtd(i915, panel);
>>  	parse_lfp_data(i915, panel);
>>  	parse_lfp_backlight(i915, panel);
>> diff --git a/drivers/gpu/drm/i915/display/intel_bios.h b/drivers/gpu/drm/i915/display/intel_bios.h
>> index b112200ae0a0..e4c268495547 100644
>> --- a/drivers/gpu/drm/i915/display/intel_bios.h
>> +++ b/drivers/gpu/drm/i915/display/intel_bios.h
>> @@ -37,6 +37,7 @@ struct edid;
>>  struct intel_bios_encoder_data;
>>  struct intel_crtc_state;
>>  struct intel_encoder;
>> +struct intel_connector;
>>  struct intel_panel;
>>  enum port;
>>  
>> @@ -233,7 +234,7 @@ struct mipi_pps_data {
>>  
>>  void intel_bios_init(struct drm_i915_private *dev_priv);
>>  void intel_bios_init_panel(struct drm_i915_private *dev_priv,
>> -			   struct intel_panel *panel,
>> +			   struct intel_connector *intel_connector,
>>  			   const struct edid *edid);
>>  void intel_bios_fini_panel(struct intel_panel *panel);
>>  void intel_bios_driver_remove(struct drm_i915_private *dev_priv);
>> diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
>> index 1bc1f6458e81..3e9b4263e1bc 100644
>> --- a/drivers/gpu/drm/i915/display/intel_dp.c
>> +++ b/drivers/gpu/drm/i915/display/intel_dp.c
>> @@ -5213,8 +5213,7 @@ static bool intel_edp_init_connector(struct intel_dp *intel_dp,
>>  	}
>>  	intel_connector->edid = edid;
>>  
>> -	intel_bios_init_panel(dev_priv, &intel_connector->panel,
>> -			      IS_ERR(edid) ? NULL : edid);
>> +	intel_bios_init_panel(dev_priv, intel_connector, IS_ERR(edid) ? NULL : edid);
>>  
>>  	intel_panel_add_edid_fixed_modes(intel_connector,
>>  					 intel_connector->panel.vbt.drrs_type != DRRS_TYPE_NONE);
>> diff --git a/drivers/gpu/drm/i915/display/intel_lvds.c b/drivers/gpu/drm/i915/display/intel_lvds.c
>> index 595f03343939..2c60267f9d37 100644
>> --- a/drivers/gpu/drm/i915/display/intel_lvds.c
>> +++ b/drivers/gpu/drm/i915/display/intel_lvds.c
>> @@ -967,8 +967,7 @@ void intel_lvds_init(struct drm_i915_private *dev_priv)
>>  	}
>>  	intel_connector->edid = edid;
>>  
>> -	intel_bios_init_panel(dev_priv, &intel_connector->panel,
>> -			      IS_ERR(edid) ? NULL : edid);
>> +	intel_bios_init_panel(dev_priv, intel_connector, IS_ERR(edid) ? NULL : edid);
>>  
>>  	/* Try EDID first */
>>  	intel_panel_add_edid_fixed_modes(intel_connector,
>> diff --git a/drivers/gpu/drm/i915/display/intel_sdvo.c b/drivers/gpu/drm/i915/display/intel_sdvo.c
>> index d9de2c4d67a7..3b7fe117bc5b 100644
>> --- a/drivers/gpu/drm/i915/display/intel_sdvo.c
>> +++ b/drivers/gpu/drm/i915/display/intel_sdvo.c
>> @@ -2901,7 +2901,7 @@ intel_sdvo_lvds_init(struct intel_sdvo *intel_sdvo, int device)
>>  	if (!intel_sdvo_create_enhance_property(intel_sdvo, intel_sdvo_connector))
>>  		goto err;
>>  
>> -	intel_bios_init_panel(i915, &intel_connector->panel, NULL);
>> +	intel_bios_init_panel(i915, intel_connector, NULL);
>>  
>>  	/*
>>  	 * Fetch modes from VBT. For SDVO prefer the VBT mode since some
>> diff --git a/drivers/gpu/drm/i915/display/intel_vbt_defs.h b/drivers/gpu/drm/i915/display/intel_vbt_defs.h
>> index 4b98bab3b890..fbda64e3a34d 100644
>> --- a/drivers/gpu/drm/i915/display/intel_vbt_defs.h
>> +++ b/drivers/gpu/drm/i915/display/intel_vbt_defs.h
>> @@ -349,6 +349,10 @@ enum vbt_gmbus_ddi {
>>  #define BDB_230_VBT_DP_MAX_LINK_RATE_UHBR13P5	6
>>  #define BDB_230_VBT_DP_MAX_LINK_RATE_UHBR20	7
>>  
>> +/* VBT info for DUAL LFP */
>> +#define HANDLE_LFP_1 0x0008
>> +#define HANDLE_LFP_2 0x0080
>
> Please move these before the DEVICE_TYPE_* macros, and name
> DEVICE_HANDLE_*. The comment should refer to device handles, and there's
> no need to mention VBT or dual LFP.
>
> BR,
> Jani.
>
>> +
>>  /*
>>   * The child device config, aka the display device data structure, provides a
>>   * description of a port and its configuration on the platform.
>> diff --git a/drivers/gpu/drm/i915/display/vlv_dsi.c b/drivers/gpu/drm/i915/display/vlv_dsi.c
>> index abda0888c8d4..114e4f89f198 100644
>> --- a/drivers/gpu/drm/i915/display/vlv_dsi.c
>> +++ b/drivers/gpu/drm/i915/display/vlv_dsi.c
>> @@ -1926,7 +1926,7 @@ void vlv_dsi_init(struct drm_i915_private *dev_priv)
>>  
>>  	intel_dsi->panel_power_off_time = ktime_get_boottime();
>>  
>> -	intel_bios_init_panel(dev_priv, &intel_connector->panel, NULL);
>> +	intel_bios_init_panel(dev_priv, intel_connector, NULL);
>>  
>>  	if (intel_connector->panel.vbt.dsi.config->dual_link)
>>  		intel_dsi->ports = BIT(PORT_A) | BIT(PORT_C);

-- 
Jani Nikula, Intel Open Source Graphics Center