soc/amd/common/block/psp: move psp_notify_dram to psp_gen1.c

The MBOX_BIOS_CMD_DRAM_INFO PSP mailbox command is only available on the
first generation of PSP mailbox interface and not on the second
generation. The second generation of the PSP mailbox interface was
introduced with the AMD family 17h SoCs on which the DRAM is already
initialized before the x86 cores are released from reset.

Signed-off-by: Felix Held <felix-coreboot@felixheld.de>
Change-Id: I97b29fdc4a71d6493ec63fa60f580778f026ec0b
Reviewed-on: https://review.coreboot.org/c/coreboot/+/60124
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Marshall Dawson <marshalldawson3rd@gmail.com>

4 files changed, 27 insertions, 25 deletions

diff --git a/src/soc/amd/common/block/include/amdblocks/psp.h b/src/soc/amd/common/block/include/amdblocks/psp.h
index e749d75df1..c9986cae00 100644
--- a/src/soc/amd/common/block/include/amdblocks/psp.h
+++ b/src/soc/amd/common/block/include/amdblocks/psp.h
@@ -51,6 +51,8 @@ void soc_fill_smm_reg_info(struct smm_register_info *reg); /* v2 only */
 #define PSPSTS_INVALID_NAME	8
 #define PSPSTS_INVALID_BLOB	9
 
+/* PSP gen1-only. SoCs with PSP gen2 already have the DRAM initialized when
+   the x86 cores are released from reset. */
 int psp_notify_dram(void);
 
 int psp_notify_smm(void);
diff --git a/src/soc/amd/common/block/psp/psp.c b/src/soc/amd/common/block/psp/psp.c
index b95545923f..66f7d59224 100644
--- a/src/soc/amd/common/block/psp/psp.c
+++ b/src/soc/amd/common/block/psp/psp.c
@@ -56,29 +56,6 @@ void psp_print_cmd_status(int cmd_status, struct mbox_buffer_header *header)
 }
 
 /*
- * Notify the PSP that DRAM is present.  Upon receiving this command, the PSP
- * will load its OS into fenced DRAM that is not accessible to the x86 cores.
- */
-int psp_notify_dram(void)
-{
-	int cmd_status;
-	struct mbox_default_buffer buffer = {
-		.header = {
-			.size = sizeof(buffer)
-		}
-	};
-
-	printk(BIOS_DEBUG, "PSP: Notify that DRAM is available... ");
-
-	cmd_status = send_psp_command(MBOX_BIOS_CMD_DRAM_INFO, &buffer);
-
-	/* buffer's status shouldn't change but report it if it does */
-	psp_print_cmd_status(cmd_status, &buffer.header);
-
-	return cmd_status;
-}
-
-/*
  * Notify the PSP that the system is completing the boot process.  Upon
  * receiving this command, the PSP will only honor commands where the buffer
  * is in SMM space.
diff --git a/src/soc/amd/common/block/psp/psp_def.h b/src/soc/amd/common/block/psp/psp_def.h
index 4d3aca59b3..5baa0642dc 100644
--- a/src/soc/amd/common/block/psp/psp_def.h
+++ b/src/soc/amd/common/block/psp/psp_def.h
@@ -8,7 +8,6 @@
 #include <amdblocks/psp.h>
 
 /* x86 to PSP commands */
-#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
@@ -19,7 +18,8 @@
 #define MBOX_BIOS_CMD_S3_DATA_INFO		0x08
 #define MBOX_BIOS_CMD_NOP			0x09
 #define MBOX_BIOS_CMD_ABORT			0xfe
-/* x86 to PSP commands, v1 */
+/* x86 to PSP commands, v1-only */
+#define MBOX_BIOS_CMD_DRAM_INFO			0x01
 #define MBOX_BIOS_CMD_SMU_FW			0x19
 #define MBOX_BIOS_CMD_SMU_FW2			0x1a
 
diff --git a/src/soc/amd/common/block/psp/psp_gen1.c b/src/soc/amd/common/block/psp/psp_gen1.c
index 55070f258d..37257ba92e 100644
--- a/src/soc/amd/common/block/psp/psp_gen1.c
+++ b/src/soc/amd/common/block/psp/psp_gen1.c
@@ -170,3 +170,26 @@ int psp_load_named_blob(enum psp_blob_type type, const char *name)
 	cbfs_unmap(blob);
 	return cmd_status;
 }
+
+/*
+ * Notify the PSP that DRAM is present.  Upon receiving this command, the PSP
+ * will load its OS into fenced DRAM that is not accessible to the x86 cores.
+ */
+int psp_notify_dram(void)
+{
+	int cmd_status;
+	struct mbox_default_buffer buffer = {
+		.header = {
+			.size = sizeof(buffer)
+		}
+	};
+
+	printk(BIOS_DEBUG, "PSP: Notify that DRAM is available... ");
+
+	cmd_status = send_psp_command(MBOX_BIOS_CMD_DRAM_INFO, &buffer);
+
+	/* buffer's status shouldn't change but report it if it does */
+	psp_print_cmd_status(cmd_status, &buffer.header);
+
+	return cmd_status;
+}