soc/amd/common/psp: Add notify_sx_info

Add the command to tell the PSP the system is going to a sleep
state.

BUG=b:153677737

Change-Id: I50da358e1f8438b46dbb1bda593becf6dd4549ea
Signed-off-by: Marshall Dawson <marshalldawson3rd@gmail.com>
Reviewed-on: https://chromium-review.googlesource.com/2020367
Reviewed-on: https://chromium-review.googlesource.com/2110764
Reviewed-on: https://chromium-review.googlesource.com/2121159
Signed-off-by: Felix Held <felix-coreboot@felixheld.de>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/40016
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Raul Rangel <rrangel@chromium.org>

src/soc/amd/common/block/include/amdblocks/psp.h

@@ -67,6 +67,12 @@ enum psp_blob_type {
 	BLOB_SMU_FW2,
 };
 
+/*
+ * Notify PSP that the system is entering a sleep state.  sleep_state uses the
+ * same definition as Pm1Cnt[SlpTyp], typically 0, 1, 3, 4, 5.
+ */
+void psp_notify_sx_info(u8 sleep_type);
+
 int psp_load_named_blob(enum psp_blob_type type, const char *name);
 
 #endif /* __AMD_PSP_H__ */

src/soc/amd/common/block/psp/psp_def.h

@@ -12,6 +12,7 @@
 #define MBOX_BIOS_CMD_DRAM_INFO			0x01
 #define MBOX_BIOS_CMD_SMM_INFO			0x02
 #define MBOX_BIOS_CMD_SX_INFO			0x03
+#define   MBOX_BIOS_CMD_SX_INFO_SLEEP_TYPE_MAX	0x07
 #define MBOX_BIOS_CMD_RSM_INFO			0x04
 #define MBOX_BIOS_CMD_PSP_QUERY			0x05
 #define MBOX_BIOS_CMD_BOOT_DONE			0x06

src/soc/amd/common/block/psp/psp_smm.c

@@ -76,3 +76,31 @@ int psp_notify_smm(void)
 
 	return cmd_status;
 }
+
+/* Notify PSP the system is going to a sleep state. */
+void psp_notify_sx_info(u8 sleep_type)
+{
+	int cmd_status;
+	struct mbox_cmd_sx_info_buffer *buffer;
+
+	/* PSP verifies that this buffer is at the address specified in psp_notify_smm() */
+	buffer = (struct mbox_cmd_sx_info_buffer *)c2p_buffer.buffer;
+	memset(buffer, 0, sizeof(*buffer));
+	buffer->header.size = sizeof(*buffer);
+
+	if (sleep_type > MBOX_BIOS_CMD_SX_INFO_SLEEP_TYPE_MAX) {
+		printk(BIOS_ERR, "PSP: BUG: invalid sleep type 0x%x requested\n", sleep_type);
+		return;
+	}
+
+	printk(BIOS_DEBUG, "PSP: Prepare to enter sleep state %d... ", sleep_type);
+
+	buffer->sleep_type = sleep_type;
+
+	set_smm_flag();
+	cmd_status = send_psp_command(MBOX_BIOS_CMD_SX_INFO, buffer);
+	clear_smm_flag();
+
+	/* buffer's status shouldn't change but report it if it does */
+	psp_print_cmd_status(cmd_status, (struct mbox_default_buffer *)buffer);
+}