[S] Change in coreboot[master]: soc/intel/common: Fix the TCSS DisplayPort detection flow

[John Zhao (Code Review)]

John Zhao has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/69694 )

Change subject: soc/intel/common: Fix the TCSS DisplayPort detection flow
......................................................................

soc/intel/common: Fix the TCSS DisplayPort detection flow

After DisplayPort is plugged into type-C port, its hpd signal is
instantly presents and EC has mux_info for dp and hpd. This change
fixes the DP detection flow to avoid the 1 second delay while no DP
is connected. If DP is present, there will be requests towards PMC
through the sequence of connect, safe mode, dp and hpd mode.

BUG=b:247670186
TEST=Built image and validated the DisplayPort preboot feature on Rex.

Change-Id: I7cb95ec7fcc7e1a86e86466e6d45390eedcc4531
Signed-off-by: zhaojohn 
---
M src/soc/intel/common/block/tcss/tcss.c
1 file changed, 21 insertions(+), 18 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/94/69694/1

diff --git a/src/soc/intel/common/block/tcss/tcss.c b/src/soc/intel/common/block/tcss/tcss.c
index df331c2..b4a5a0e 100644
--- a/src/soc/intel/common/block/tcss/tcss.c
+++ b/src/soc/intel/common/block/tcss/tcss.c
@@ -202,7 +202,6 @@
    req.buf[0] = cmd;

return send_pmc_req(HPD_REQ, &req, &rsp, PMC_IPC_HPD_REQ_SIZE);
-
 }

static int send_pmc_dp_mode_request(int port, const struct usbc_mux_info *mux_data,
@@ -287,7 +286,7 @@

static void tcss_configure_dp_mode(const struct tcss_port_map *port_map, size_t num_ports)
 {
-	int ret, port_bitmask;
+	int ret;
    size_t i;
    const struct usbc_ops *ops;
    struct usbc_mux_info mux_info;
@@ -300,24 +299,9 @@
    if (ops == NULL)
    	return;

-	port_bitmask = ops->dp_ops.wait_for_connection(WAIT_FOR_DISPLAYPORT_TIMEOUT_MS);
-	if (!port_bitmask)	/* No DP device is connected */
-		return;
-
    for (i = 0; i < num_ports; i++) {
-		if (!(port_bitmask & BIT(i)))
-			continue;
-
-		ret = ops->dp_ops.enter_dp_mode(i);
-		if (ret < 0)
-			continue;
-
-		ret = ops->dp_ops.wait_for_hpd(i, WAIT_FOR_HPD_TIMEOUT_MS);
-		if (ret < 0)
-			continue;
-
    	ret = ops->mux_ops.get_mux_info(i, &mux_info);
-		if (ret < 0)
+		if ((ret < 0) || (!mux_info.dp))
    		continue;

port_info = &port_map[i];