soc/intel/skylake: Support logging wake source in SMM

This change adds support for logging wake source information in gsmi
callbacks. With this change, all the elog logging infrastructure can
be used for S0ix as well as S3 on skylake.

BUG=b:67874513

Change-Id: Ie1f81e956fe0bbe2e5e4c706f27997b7bd30d5e0
Signed-off-by: Furquan Shaikh <furquan@chromium.org>
Reviewed-on: https://review.coreboot.org/22086
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

src/soc/intel/skylake/Makefile.inc

@@ -72,6 +72,7 @@ ramstage-y += uart.c
 ramstage-$(CONFIG_UART_DEBUG) += uart_debug.c
 ramstage-y += vr_config.c
 
+smm-y += elog.c
 smm-y += gpio.c
 smm-y += pch.c
 smm-y += pmutil.c

src/soc/intel/skylake/elog.c

@@ -20,6 +20,7 @@
 #include <device/pci_ops.h>
 #include <stdint.h>
 #include <elog.h>
+#include <intelblocks/pmclib.h>
 #include <soc/pci_devs.h>
 #include <soc/pm.h>
 #include <soc/smbus.h>
@@ -382,3 +383,10 @@ static void pch_log_state(void *unused)
 }
 
 BOOT_STATE_INIT_ENTRY(BS_DEV_INIT, BS_ON_EXIT, pch_log_state, NULL);
+
+void elog_gsmi_cb_platform_log_wake_source(void)
+{
+	struct chipset_power_state ps;
+	pmc_fill_pm_reg_info(&ps);
+	pch_log_wake_source(&ps);
+}