Commit 6a0114e0 authored by Rodrigo Siqueira's avatar Rodrigo Siqueira Committed by Alex Deucher
Browse files

drm/amd/display: Add kernel doc for commit sequence 



Add basic kernel-doc that describes some of the struct and functions
that are part of the DC commit sequence..

Tested-by: default avatarMark Broadworth <mark.broadworth@amd.com>
Reviewed-by: default avatarAurabindo Pillai <Aurabindo.Pillai@amd.com>
Acked-by: default avatarRodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: default avatarRodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
parent fa0fc4fb

drivers/gpu/drm/amd/display/dc/core/dc.c

+53 −10
Original line number Diff line number Diff line
@@ -1714,8 +1714,13 @@ void dc_z10_save_init(struct dc *dc) 
		dc->hwss.z10_save_init(dc);

}



/*

 * Applies given context to HW and copy it into current context.

/**

 * dc_commit_state_no_check - Apply context to the hardware

 *

 * @dc: DC object with the current status to be updated

 * @context: New state that will become the current status at the end of this function

 *

 * Applies given context to the hardware and copy it into current context.

 * It's up to the user to release the src context afterwards.

 */

static enum dc_status dc_commit_state_no_check(struct dc *dc, struct dc_state *context)
@@ -3651,10 +3656,24 @@ static void commit_planes_for_stream(struct dc *dc, 
	}

}



/* Determines if the incoming context requires a applying transition state with unnecessary

 * pipe splitting and ODM disabled, due to hardware limitations. In a case where

 * the OPP associated with an MPCC might change due to plane additions, this function

/**

 * could_mpcc_tree_change_for_active_pipes - Check if an OPP associated with MPCC might change

 *

 * @dc: Used to get the current state status

 * @stream: Target stream, which we want to remove the attached planes

 * @surface_count: Number of surface update

 * @is_plane_addition: [in] Fill out with true if it is a plane addition case

 *

 * DCN32x and newer support a feature named Dynamic ODM which can conflict with

 * the MPO if used simultaneously in some specific configurations (e.g.,

 * 4k@144). This function checks if the incoming context requires applying a

 * transition state with unnecessary pipe splitting and ODM disabled to

 * circumvent our hardware limitations to prevent this edge case. If the OPP

 * associated with an MPCC might change due to plane additions, this function

 * returns true.

 *

 * Return:

 * Return true if OPP and MPCC might change, otherwise, return false.

 */

static bool could_mpcc_tree_change_for_active_pipes(struct dc *dc,

		struct dc_stream_state *stream,
@@ -3729,6 +3748,24 @@ static bool could_mpcc_tree_change_for_active_pipes(struct dc *dc, 
	return force_minimal_pipe_splitting;

}



/**

 * commit_minimal_transition_state - Create a transition pipe split state

 *

 * @dc: Used to get the current state status

 * @transition_base_context: New transition state

 *

 * In some specific configurations, such as pipe split on multi-display with

 * MPO and/or Dynamic ODM, removing a plane may cause unsupported pipe

 * programming when moving to new planes. To mitigate those types of problems,

 * this function adds a transition state that minimizes pipe usage before

 * programming the new configuration. When adding a new plane, the current

 * state requires the least pipes, so it is applied without splitting. When

 * removing a plane, the new state requires the least pipes, so it is applied

 * without splitting.

 *

 * Return:

 * Return false if something is wrong in the transition state.

 */

static bool commit_minimal_transition_state(struct dc *dc,

		struct dc_state *transition_base_context)

{
@@ -3742,6 +3779,10 @@ static bool commit_minimal_transition_state(struct dc *dc, 


	if (!transition_context)

		return false;

	/* Setup:

	 * Store the current ODM and MPC config in some temp variables to be

	 * restored after we commit the transition state.

	 */



	/* check current pipes in use*/

	for (i = 0; i < dc->res_pool->pipe_count; i++) {
@@ -3777,7 +3818,7 @@ static bool commit_minimal_transition_state(struct dc *dc, 


	dc_resource_state_copy_construct(transition_base_context, transition_context);



	//commit minimal state

	/* commit minimal state */

	if (dc->res_pool->funcs->validate_bandwidth(dc, transition_context, false)) {

		for (i = 0; i < transition_context->stream_count; i++) {

			struct dc_stream_status *stream_status = &transition_context->stream_status[i];
@@ -3798,7 +3839,9 @@ static bool commit_minimal_transition_state(struct dc *dc, 
	/* always release as dc_commit_state_no_check retains in good case */

	dc_release_state(transition_context);



	/*restore previous pipe split and odm policy*/

	/* TearDown:

	 * Restore original configuration for ODM and MPO.

	 */

	if (!dc->config.is_vmin_only_asic)

		dc->debug.pipe_split_policy = tmp_mpc_policy;

drivers/gpu/drm/amd/display/dc/core/dc_resource.c

+11 −0
Original line number Diff line number Diff line
@@ -1768,6 +1768,17 @@ bool dc_remove_plane_from_context( 
	return true;

}



/**

 * dc_rem_all_planes_for_stream - Remove planes attached to the target stream.

 *

 * @dc: Current dc state.

 * @stream: Target stream, which we want to remove the attached plans.

 * @context: New context.

 *

 * Return:

 * Return true if DC was able to remove all planes from the target

 * stream, otherwise, return false.

 */

bool dc_rem_all_planes_for_stream(

		const struct dc *dc,

		struct dc_stream_state *stream,

drivers/gpu/drm/amd/display/dc/inc/core_types.h

+15 −1
Original line number Diff line number Diff line
@@ -420,7 +420,10 @@ struct pipe_ctx { 


	struct pll_settings pll_settings;



	/* link config records software decision for what link config should be

	/**

	 * @link_config:

	 *

	 * link config records software decision for what link config should be

	 * enabled given current link capability and stream during hw resource

	 * mapping. This is to decouple the dependency on link capability during

	 * dc commit or update.
@@ -542,6 +545,10 @@ struct dc_state { 


	/**

	 * @bw_ctx: The output from bandwidth and watermark calculations and the DML

	 *

	 * Each context must have its own instance of VBA, and in order to

	 * initialize and obtain IP and SOC, the base DML instance from DC is

	 * initially copied into every context.

	 */

	struct bw_context bw_ctx;
@@ -559,6 +566,13 @@ struct dc_state { 


	struct clk_mgr *clk_mgr;



	/**

	 * @refcount: refcount reference

	 *

	 * Notice that dc_state is used around the code to capture the current

	 * context, so we need to pass it everywhere. That's why we want to use

	 * kref in this struct.

	 */

	struct kref refcount;



	struct {