drm/amd/display: break down dc_link.c

[why]
dc_link contains over 30k line of code, the decision is to break it
down to files residing in link folder based on functionality. This
change is the last break down change which will remove dc_link.c
file after everything is broken down.

[how]
Move remaining dc_link.c functions into link_detection, link_dpms,
link_validation, link_resource, and link_fpga and remove dc_link.

Reviewed-by: George Shen <[email protected]>
Acked-by: Qingqing Zhuo <[email protected]>
Signed-off-by: Wenjing Liu <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>

1 files changed, 149 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/display/dc/link/link_resource.c b/drivers/gpu/drm/amd/display/dc/link/link_resource.c
new file mode 100644
index 000000000000..0027a7206073
--- /dev/null
+++ b/drivers/gpu/drm/amd/display/dc/link/link_resource.c
@@ -0,0 +1,149 @@
+/*
+ * Copyright 2023 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ *
+ * Authors: AMD
+ *
+ */
+/* FILE POLICY AND INTENDED USAGE:
+ * This file implements accessors to link resource.
+ */
+
+#include "link_resource.h"
+#include "protocols/link_dp_capability.h"
+
+void dc_link_get_cur_link_res(const struct dc_link *link,
+		struct link_resource *link_res)
+{
+	int i;
+	struct pipe_ctx *pipe = NULL;
+
+	memset(link_res, 0, sizeof(*link_res));
+
+	for (i = 0; i < MAX_PIPES; i++) {
+		pipe = &link->dc->current_state->res_ctx.pipe_ctx[i];
+		if (pipe->stream && pipe->stream->link && pipe->top_pipe == NULL) {
+			if (pipe->stream->link == link) {
+				*link_res = pipe->link_res;
+				break;
+			}
+		}
+	}
+
+}
+
+/**
+ * dc_get_cur_link_res_map() - take a snapshot of current link resource allocation state
+ * @dc: pointer to dc of the dm calling this
+ * @map: a dc link resource snapshot defined internally to dc.
+ *
+ * DM needs to capture a snapshot of current link resource allocation mapping
+ * and store it in its persistent storage.
+ *
+ * Some of the link resource is using first come first serve policy.
+ * The allocation mapping depends on original hotplug order. This information
+ * is lost after driver is loaded next time. The snapshot is used in order to
+ * restore link resource to its previous state so user will get consistent
+ * link capability allocation across reboot.
+ *
+ * Return: none (void function)
+ *
+ */
+void dc_get_cur_link_res_map(const struct dc *dc, uint32_t *map)
+{
+	struct dc_link *link;
+	uint32_t i;
+	uint32_t hpo_dp_recycle_map = 0;
+
+	*map = 0;
+
+	if (dc->caps.dp_hpo) {
+		for (i = 0; i < dc->caps.max_links; i++) {
+			link = dc->links[i];
+			if (link->link_status.link_active &&
+					link_dp_get_encoding_format(&link->reported_link_cap) == DP_128b_132b_ENCODING &&
+					link_dp_get_encoding_format(&link->cur_link_settings) != DP_128b_132b_ENCODING)
+				/* hpo dp link encoder is considered as recycled, when RX reports 128b/132b encoding capability
+				 * but current link doesn't use it.
+				 */
+				hpo_dp_recycle_map |= (1 << i);
+		}
+		*map |= (hpo_dp_recycle_map << LINK_RES_HPO_DP_REC_MAP__SHIFT);
+	}
+}
+
+/**
+ * dc_restore_link_res_map() - restore link resource allocation state from a snapshot
+ * @dc: pointer to dc of the dm calling this
+ * @map: a dc link resource snapshot defined internally to dc.
+ *
+ * DM needs to call this function after initial link detection on boot and
+ * before first commit streams to restore link resource allocation state
+ * from previous boot session.
+ *
+ * Some of the link resource is using first come first serve policy.
+ * The allocation mapping depends on original hotplug order. This information
+ * is lost after driver is loaded next time. The snapshot is used in order to
+ * restore link resource to its previous state so user will get consistent
+ * link capability allocation across reboot.
+ *
+ * Return: none (void function)
+ *
+ */
+void dc_restore_link_res_map(const struct dc *dc, uint32_t *map)
+{
+	struct dc_link *link;
+	uint32_t i;
+	unsigned int available_hpo_dp_count;
+	uint32_t hpo_dp_recycle_map = (*map & LINK_RES_HPO_DP_REC_MAP__MASK)
+			>> LINK_RES_HPO_DP_REC_MAP__SHIFT;
+
+	if (dc->caps.dp_hpo) {
+		available_hpo_dp_count = dc->res_pool->hpo_dp_link_enc_count;
+		/* remove excess 128b/132b encoding support for not recycled links */
+		for (i = 0; i < dc->caps.max_links; i++) {
+			if ((hpo_dp_recycle_map & (1 << i)) == 0) {
+				link = dc->links[i];
+				if (link->type != dc_connection_none &&
+						link_dp_get_encoding_format(&link->verified_link_cap) == DP_128b_132b_ENCODING) {
+					if (available_hpo_dp_count > 0)
+						available_hpo_dp_count--;
+					else
+						/* remove 128b/132b encoding capability by limiting verified link rate to HBR3 */
+						link->verified_link_cap.link_rate = LINK_RATE_HIGH3;
+				}
+			}
+		}
+		/* remove excess 128b/132b encoding support for recycled links */
+		for (i = 0; i < dc->caps.max_links; i++) {
+			if ((hpo_dp_recycle_map & (1 << i)) != 0) {
+				link = dc->links[i];
+				if (link->type != dc_connection_none &&
+						link_dp_get_encoding_format(&link->verified_link_cap) == DP_128b_132b_ENCODING) {
+					if (available_hpo_dp_count > 0)
+						available_hpo_dp_count--;
+					else
+						/* remove 128b/132b encoding capability by limiting verified link rate to HBR3 */
+						link->verified_link_cap.link_rate = LINK_RATE_HIGH3;
+				}
+			}
+		}
+	}
+}