soc/intel/skylake: Add PcieRpClkSrcNumber UPD configuartion support

New UPD PcieRpClkSrcNumber introduced in FSP V2.9.2 to configure
clock source number of PCIe root ports. This UPD array is set to clock
source number(0-6) for all the enabled PCIe root ports, invalid(0x1F)
is set for disabled PCIe root ports.

BUG=b:70252901
BRANCH=None
TEST= Perform the following
1. Build and boot soraka
2. Verify PCIe devices list using lspci command
3. Perform Basic Assurance Test(BAT) on soraka

Change-Id: I95ca0d893338100b7e4d7d0b76c076ed7e2b040e
Signed-off-by: Divya Chellap <divya.chellappa@intel.com>
Reviewed-on: https://review.coreboot.org/22947
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Subrata Banik <subrata.banik@intel.com>
Reviewed-by: Furquan Shaikh <furquan@google.com>
diff --git a/src/soc/intel/skylake/chip_fsp20.c b/src/soc/intel/skylake/chip_fsp20.c
index 96c3b60..24a239e 100644
--- a/src/soc/intel/skylake/chip_fsp20.c
+++ b/src/soc/intel/skylake/chip_fsp20.c
@@ -166,6 +166,19 @@
 	memcpy(params->PcieRpLtrEnable, config->PcieRpLtrEnable,
 	       sizeof(params->PcieRpLtrEnable));
 
+	/*
+	 * PcieRpClkSrcNumber UPD is set to clock source number(0-6) for
+	 * all the enabled PCIe root ports, invalid(0x1F) is set for
+	 * disabled PCIe root ports.
+	 */
+	for (i = 0; i < CONFIG_MAX_ROOT_PORTS; i++) {
+		if (config->PcieRpClkReqSupport[i])
+			params->PcieRpClkSrcNumber[i] =
+				config->PcieRpClkSrcNumber[i];
+		else
+			params->PcieRpClkSrcNumber[i] = 0x1F;
+	}
+
 	/* disable Legacy PME */
 	memset(params->PcieRpPmSci, 0, sizeof(params->PcieRpPmSci));