soc/amd/mendocino: Add code for printing STB to boot log

This adds the mendocino specific code for printing the STB data to the
boot log.  It still needs to be enabled in the mainboard to be used.

Signed-off-by: Martin Roth <gaumless@gmail.com>
Change-Id: I249507a97ed6c44805e9e66a6ea23f200d62cf66
Reviewed-on: https://review.coreboot.org/c/coreboot/+/68544
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Fred Reitberger <reitbergerfred@gmail.com>

src/soc/amd/mendocino/Kconfig

@@ -84,6 +84,7 @@ config SOC_SPECIFIC_OPTIONS
 	select SOC_AMD_COMMON_BLOCK_SMM		# TODO: Check if this is still correct
 	select SOC_AMD_COMMON_BLOCK_SMU
 	select SOC_AMD_COMMON_BLOCK_SPI		# TODO: Check if this is still correct
+	select SOC_AMD_COMMON_BLOCK_STB
 	select SOC_AMD_COMMON_BLOCK_TSC_FAM17H_19H	# TODO: Check if this is still correct
 	select SOC_AMD_COMMON_BLOCK_UART
 	select SOC_AMD_COMMON_BLOCK_UCODE

src/soc/amd/mendocino/early_fch.c

@@ -9,6 +9,7 @@
 #include <amdblocks/lpc.h>
 #include <amdblocks/pmlib.h>
 #include <amdblocks/smbus.h>
+#include <amdblocks/stb.h>
 #include <amdblocks/uart.h>
 #include <soc/i2c.h>
 #include <soc/southbridge.h>
@@ -54,6 +55,9 @@ void fch_pre_init(void)
 /* After console init */
 void fch_early_init(void)
 {
+	if (CONFIG(WRITE_STB_BUFFER_TO_CONSOLE))
+		write_stb_to_console();
+
 	reset_i2c_peripherals();
 	pm_set_power_failure_state();
 	fch_print_pmxc0_status();

src/soc/amd/mendocino/include/soc/stb.h

@@ -0,0 +1,9 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#ifndef AMD_MENDOCINO_STB_H
+#define AMD_MENDOCINO_STB_H
+
+#define STB_CFG_SMN_ADDR		0x3E00000
+#define AMD_STB_SDRAM_FIFO_SIZE		2048
+
+#endif /* AMD_MENDOCINO_STB_H */

src/soc/amd/mendocino/romstage.c

@@ -6,6 +6,7 @@
 #include <amdblocks/acpimmio.h>
 #include <amdblocks/memmap.h>
 #include <amdblocks/pmlib.h>
+#include <amdblocks/stb.h>
 #include <arch/cpu.h>
 #include <console/console.h>
 #include <fsp/api.h>
@@ -16,6 +17,9 @@ void __noreturn romstage_main(void)
 {
 	post_code(0x40);
 
+	if (CONFIG(WRITE_STB_BUFFER_TO_CONSOLE))
+		write_stb_to_console();
+
 	/* Snapshot chipset state prior to any FSP call */
 	fill_chipset_state();