soc/intel/alderlake: Implement function to map physical port to EC port

Currently coreboot and EC had different logic to interpret TCSS port
number which would break retimer update functionality since coreboot
would pass wrong port information to EC.

To correct this, coreboot has implemented function which converts
coreboot physical port mapping to EC's abstract port mapping.

Each SoC needs to implement this weak function since only SoC will have
correct physical port mapping data. This function should resolve issue
of port mismatch since coreboot will count only enabled ports and
provide correct EC port number in return.

BUG=b:207057940
BRANCH=None
TEST=Check if retimer update works on Redrix and correct port
information is passed to EC.

Change-Id: I3735b7c7794b46123aba3beac8c0268ce72d658c
Signed-off-by: MAULIK V VAGHELA <maulik.v.vaghela@intel.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/59666
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Tim Wawrzynczak <twawrzynczak@chromium.org>

2 files changed, 33 insertions, 0 deletions

diff --git a/src/soc/intel/alderlake/Makefile.inc b/src/soc/intel/alderlake/Makefile.inc
index 6962ab2695..d2c48b74c8 100644
--- a/src/soc/intel/alderlake/Makefile.inc
+++ b/src/soc/intel/alderlake/Makefile.inc
@@ -39,6 +39,7 @@ ramstage-y += p2sb.c
 ramstage-y += pcie_rp.c
 ramstage-y += pmc.c
 ramstage-y += reset.c
+ramstage-y += retimer.c
 ramstage-y += soundwire.c
 ramstage-y += systemagent.c
 ramstage-y += vr_config.c
diff --git a/src/soc/intel/alderlake/retimer.c b/src/soc/intel/alderlake/retimer.c
new file mode 100644
index 0000000000..09bf112160
--- /dev/null
+++ b/src/soc/intel/alderlake/retimer.c
@@ -0,0 +1,32 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#include <console/console.h>
+#include <device/device.h>
+#include <drivers/intel/usb4/retimer/retimer.h>
+#include <intelblocks/tcss.h>
+
+int retimer_get_index_for_typec(uint8_t typec_port)
+{
+	int ec_port = 0;
+
+	const struct device *tcss_port_arr[] = {
+		DEV_PTR(tcss_usb3_port1),
+		DEV_PTR(tcss_usb3_port2),
+		DEV_PTR(tcss_usb3_port3),
+		DEV_PTR(tcss_usb3_port4),
+	};
+
+	for (uint8_t i = 0; i < MAX_TYPE_C_PORTS; i++) {
+		if (i == typec_port) {
+			printk(BIOS_ERR, "USB Type-C %d mapped to EC port %d\n", typec_port,
+					ec_port);
+			return ec_port;
+		}
+
+		if (is_dev_enabled(tcss_port_arr[i]))
+			ec_port++;
+	}
+
+	// Code should not come here if typec_port input is correct
+	return -1;
+}