Commit 3b00b53a authored by Jani Nikula's avatar Jani Nikula
Browse files

drm/dp: extract drm_dp_dpcd_write_payload() 



SST with 128b/132b channel coding needs this too. Extract to a separate
helper, independent of MST.

v2: Clean up kernel-doc a bit

Cc: Lyude Paul <lyude@redhat.com>
Reviewed-by: default avatarImre Deak <imre.deak@intel.com>
Reviewed-by: default avatarLyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/f626715ba4e348546770750aa3e10fac73a5cbd7.1733238941.git.jani.nikula@intel.com


Signed-off-by: default avatarJani Nikula <jani.nikula@intel.com>
parent f2663f70

drivers/gpu/drm/display/drm_dp_helper.c

+57 −0
Original line number Diff line number Diff line
@@ -792,6 +792,63 @@ static int read_payload_update_status(struct drm_dp_aux *aux) 
	return status;

}



/**

 * drm_dp_dpcd_write_payload() - Write Virtual Channel information to payload table

 * @aux: DisplayPort AUX channel

 * @vcpid: Virtual Channel Payload ID

 * @start_time_slot: Starting time slot

 * @time_slot_count: Time slot count

 *

 * Write the Virtual Channel payload allocation table, checking the payload

 * update status and retrying as necessary.

 *

 * Returns:

 * 0 on success, negative error otherwise

 */

int drm_dp_dpcd_write_payload(struct drm_dp_aux *aux,

			      int vcpid, u8 start_time_slot, u8 time_slot_count)

{

	u8 payload_alloc[3], status;

	int ret;

	int retries = 0;



	drm_dp_dpcd_writeb(aux, DP_PAYLOAD_TABLE_UPDATE_STATUS,

			   DP_PAYLOAD_TABLE_UPDATED);



	payload_alloc[0] = vcpid;

	payload_alloc[1] = start_time_slot;

	payload_alloc[2] = time_slot_count;



	ret = drm_dp_dpcd_write(aux, DP_PAYLOAD_ALLOCATE_SET, payload_alloc, 3);

	if (ret != 3) {

		drm_dbg_kms(aux->drm_dev, "failed to write payload allocation %d\n", ret);

		goto fail;

	}



retry:

	ret = drm_dp_dpcd_readb(aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);

	if (ret < 0) {

		drm_dbg_kms(aux->drm_dev, "failed to read payload table status %d\n", ret);

		goto fail;

	}



	if (!(status & DP_PAYLOAD_TABLE_UPDATED)) {

		retries++;

		if (retries < 20) {

			usleep_range(10000, 20000);

			goto retry;

		}

		drm_dbg_kms(aux->drm_dev, "status not set after read payload table status %d\n",

			    status);

		ret = -EINVAL;

		goto fail;

	}

	ret = 0;

fail:

	return ret;

}

EXPORT_SYMBOL(drm_dp_dpcd_write_payload);



/**

 * drm_dp_dpcd_poll_act_handled() - Poll for ACT handled status

 * @aux: DisplayPort AUX channel

drivers/gpu/drm/display/drm_dp_mst_topology.c

+3 −49
Original line number Diff line number Diff line
@@ -67,9 +67,6 @@ static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr, 


static void drm_dp_mst_topology_put_port(struct drm_dp_mst_port *port);



static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr,

				     int id, u8 start_slot, u8 num_slots);



static int drm_dp_send_dpcd_read(struct drm_dp_mst_topology_mgr *mgr,

				 struct drm_dp_mst_port *port,

				 int offset, int size, u8 *bytes);
@@ -3263,7 +3260,7 @@ EXPORT_SYMBOL(drm_dp_send_query_stream_enc_status); 
static int drm_dp_create_payload_at_dfp(struct drm_dp_mst_topology_mgr *mgr,

					struct drm_dp_mst_atomic_payload *payload)

{

	return drm_dp_dpcd_write_payload(mgr, payload->vcpi, payload->vc_start_slot,

	return drm_dp_dpcd_write_payload(mgr->aux, payload->vcpi, payload->vc_start_slot,

					 payload->time_slots);

}
@@ -3294,7 +3291,7 @@ static void drm_dp_destroy_payload_at_remote_and_dfp(struct drm_dp_mst_topology_ 
	}



	if (payload->payload_allocation_status == DRM_DP_MST_PAYLOAD_ALLOCATION_DFP)

		drm_dp_dpcd_write_payload(mgr, payload->vcpi, payload->vc_start_slot, 0);

		drm_dp_dpcd_write_payload(mgr->aux, payload->vcpi, payload->vc_start_slot, 0);

}



/**
@@ -3682,7 +3679,7 @@ int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool ms 
			goto out_unlock;



		/* Write reset payload */

		drm_dp_dpcd_write_payload(mgr, 0, 0, 0x3f);

		drm_dp_dpcd_write_payload(mgr->aux, 0, 0, 0x3f);



		drm_dp_mst_queue_probe_work(mgr);
@@ -4679,49 +4676,6 @@ void drm_dp_mst_update_slots(struct drm_dp_mst_topology_state *mst_state, uint8_ 
}

EXPORT_SYMBOL(drm_dp_mst_update_slots);



static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr,

				     int id, u8 start_slot, u8 num_slots)

{

	u8 payload_alloc[3], status;

	int ret;

	int retries = 0;



	drm_dp_dpcd_writeb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS,

			   DP_PAYLOAD_TABLE_UPDATED);



	payload_alloc[0] = id;

	payload_alloc[1] = start_slot;

	payload_alloc[2] = num_slots;



	ret = drm_dp_dpcd_write(mgr->aux, DP_PAYLOAD_ALLOCATE_SET, payload_alloc, 3);

	if (ret != 3) {

		drm_dbg_kms(mgr->dev, "failed to write payload allocation %d\n", ret);

		goto fail;

	}



retry:

	ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status);

	if (ret < 0) {

		drm_dbg_kms(mgr->dev, "failed to read payload table status %d\n", ret);

		goto fail;

	}



	if (!(status & DP_PAYLOAD_TABLE_UPDATED)) {

		retries++;

		if (retries < 20) {

			usleep_range(10000, 20000);

			goto retry;

		}

		drm_dbg_kms(mgr->dev, "status not set after read payload table status %d\n",

			    status);

		ret = -EINVAL;

		goto fail;

	}

	ret = 0;

fail:

	return ret;

}



/**

 * drm_dp_check_act_status() - Polls for ACT handled status.

 * @mgr: manager to use

include/drm/display/drm_dp_helper.h

+2 −0
Original line number Diff line number Diff line
@@ -567,6 +567,8 @@ int drm_dp_dpcd_read_phy_link_status(struct drm_dp_aux *aux, 
				     enum drm_dp_phy dp_phy,

				     u8 link_status[DP_LINK_STATUS_SIZE]);



int drm_dp_dpcd_write_payload(struct drm_dp_aux *aux,

			      int vcpid, u8 start_time_slot, u8 time_slot_count);

int drm_dp_dpcd_poll_act_handled(struct drm_dp_aux *aux, int timeout_ms);



bool drm_dp_send_real_edid_checksum(struct drm_dp_aux *aux,