soc/amd/stoneyridge: Add ELOG to SMM

1. Add ELOG entries to smihandler.c
2. Add save_state utilities that are needed by southbridge_smi_gsmi

BUG=b:65485690

Change-Id: I458babe1694f042215dd0e1c3277856e340de86f
Signed-off-by: John E. Kabat Jr <john.kabat@scarletltd.com>
Reviewed-on: https://review.coreboot.org/21728
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

src/soc/amd/stoneyridge/smihandler.c

@@ -24,6 +24,66 @@
 #include <device/pci_def.h>
 #include <soc/smi.h>
 #include <soc/southbridge.h>
+#include <elog.h>
+
+/* bits in smm_io_trap   */
+#define SMM_IO_TRAP_PORT_OFFSET		16
+#define SMM_IO_TRAP_PORT_ADDRESS_MASK	0xffff
+#define SMM_IO_TRAP_RW			(1 << 0)
+#define SMM_IO_TRAP_VALID		(1 << 1)
+
+static inline u16 get_io_address(u32 info)
+{
+	return ((info >> SMM_IO_TRAP_PORT_OFFSET) &
+		SMM_IO_TRAP_PORT_ADDRESS_MASK);
+}
+
+static void *find_save_state(int cmd)
+{
+	int core;
+	amd64_smm_state_save_area_t *state;
+	u32 smm_io_trap;
+	u8 reg_al;
+
+	/* Check all nodes looking for the one that issued the IO */
+	for (core = 0; core < CONFIG_MAX_CPUS; core++) {
+		state = smm_get_save_state(core);
+		smm_io_trap = state->smm_io_trap_offset;
+		/* Check for Valid IO Trap Word (bit1==1) */
+		if (!(smm_io_trap & SMM_IO_TRAP_VALID))
+			continue;
+		/* Make sure it was a write (bit0==0) */
+		if (smm_io_trap & SMM_IO_TRAP_RW)
+			continue;
+		/* Check for APMC IO port */
+		if (pm_acpi_smi_cmd_port() != get_io_address(smm_io_trap))
+			continue;
+		/* Check AL against the requested command */
+		reg_al = state->rax;
+		if (reg_al == cmd)
+			return state;
+	}
+	return NULL;
+}
+
+static void southbridge_smi_gsmi(void)
+{
+	u8 sub_command;
+	amd64_smm_state_save_area_t *io_smi;
+	u32 reg_ebx;
+
+	io_smi = find_save_state(ELOG_GSMI_APM_CNT);
+	if (!io_smi)
+		return;
+	/* Command and return value in EAX */
+	sub_command = (io_smi->rax >> 8) & 0xff;
+
+	/* Parameter buffer in EBX */
+	reg_ebx = io_smi->rbx;
+
+	/* drivers/elog/gsmi.c */
+	io_smi->rax = gsmi_exec(sub_command, &reg_ebx);
+}
 
 static void sb_apmc_smi_handler(void)
 {
@@ -41,6 +101,10 @@ static void sb_apmc_smi_handler(void)
 		reg32 &= ~(1 << 0);	/* clear SCI_EN */
 		outl(ACPI_PM1_CNT_BLK, reg32);
 		break;
+	case ELOG_GSMI_APM_CNT:
+		if (IS_ENABLED(CONFIG_ELOG_GSMI))
+			southbridge_smi_gsmi();
+		break;
 	}
 
 	mainboard_smi_apmc(cmd);
@@ -88,6 +152,10 @@ static void sb_slp_typ_handler(void)
 	}
 
 	if (slp_typ >= ACPI_S3) {
+		/* Sleep Type Elog S3, S4, and S5 entry */
+		if (IS_ENABLED(CONFIG_ELOG_GSMI))
+			elog_add_event_byte(ELOG_TYPE_ACPI_ENTER, slp_typ);
+
 		wbinvd();
 
 		disable_all_smi_status();