[coreboot-gerrit] Change in coreboot[master]: mb/prodrive/hermes: Define board settings in EEPROM

[Angel Pons (Code Review)]

Angel Pons has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/48806 )

Change subject: mb/prodrive/hermes: Define board settings in EEPROM
......................................................................

mb/prodrive/hermes: Define board settings in EEPROM

Hermes has an EEPROM with firmware configuration data. Add definitions
to read and verify the `board settings` from the EEPROM. Subsequent
commits will hook up these EEPROM settings.

Change-Id: Id86632192ae53fd6b0e4df5b26b5a0a81e972818
Signed-off-by: Angel Pons 
---
M src/mainboard/prodrive/hermes/eeprom.c
M src/mainboard/prodrive/hermes/variants/baseboard/include/eeprom.h
2 files changed, 45 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/06/48806/1

diff --git a/src/mainboard/prodrive/hermes/eeprom.c b/src/mainboard/prodrive/hermes/eeprom.c
index d7ecdec..2bfdd2f 100644
--- a/src/mainboard/prodrive/hermes/eeprom.c
+++ b/src/mainboard/prodrive/hermes/eeprom.c
@@ -2,12 +2,17 @@

#include <device/pci_ops.h>
 #include <console/console.h>
+#include <crc_byte.h>
 #include <device/smbus_host.h>
 #include <soc/intel/common/block/smbus/smbuslib.h>
+#include <types.h>
+
 #include "variants/baseboard/include/eeprom.h"

#define I2C_ADDR_EEPROM 0x57

+#define EEPROM_OFFSET_BOARD_SETTINGS 0x1f00
+
 /*
  * Check Signature in EEPROM (M24C32-FMN6TP)
  * If signature is there we assume that that the content is valid
@@ -28,6 +33,27 @@
    return 0;
 }

+/*
+ * Read board settings from the EEPROM and verify their checksum.
+ * If checksum is valid, we assume the settings are sane as well.
+ */
+bool get_board_settings_from_eeprom(struct eeprom_board_settings *board_cfg)
+{
+	if (read_write_config(board_cfg, EEPROM_OFFSET_BOARD_SETTINGS, 0, sizeof(*board_cfg))) {
+		printk(BIOS_ERR, "CFG EEPROM: Failed to read board settings\n");
+		return false;
+	}
+
+	const uint32_t crc =
+		CRC(&board_cfg->raw_settings, sizeof(board_cfg->raw_settings), crc32_byte);
+
+	if (crc != board_cfg->signature) {
+		printk(BIOS_ERR, "CFG EEPROM: Board settings have invalid checksum\n");
+		return false;
+	}
+	return true;
+}
+
 /* Read data from offset and write it to offset in UPD */
 bool read_write_config(void *blob, size_t read_offset, size_t write_offset, size_t size)
 {
diff --git a/src/mainboard/prodrive/hermes/variants/baseboard/include/eeprom.h b/src/mainboard/prodrive/hermes/variants/baseboard/include/eeprom.h
index 95024b6..8abef56 100644
--- a/src/mainboard/prodrive/hermes/variants/baseboard/include/eeprom.h
+++ b/src/mainboard/prodrive/hermes/variants/baseboard/include/eeprom.h
@@ -18,6 +18,24 @@
    				.size = member_size(FSP_S_CONFIG, x)}
 #endif /* ENV_ROMSTAGE */

+__packed struct eeprom_board_settings {
+	uint32_t signature;
+	union {
+		struct {
+			uint8_t secureboot;
+			uint8_t primary_video;
+			uint8_t deep_sx_enabled;
+			uint8_t wake_on_usb;
+			uint8_t usb_powered_in_s5;
+			uint8_t power_state_after_g3;
+			uint8_t blue_rear_vref;
+			uint8_t internal_audio_connection;
+			uint8_t pxe_boot_capability;
+		};
+		uint8_t raw_settings[9];
+	};
+};
+
 typedef struct {
    size_t offset;
    size_t size;
@@ -25,3 +43,4 @@

bool read_write_config(void *blob, size_t read_offset, size_t write_offset, size_t size);
 int check_signature(const size_t offset, const uint64_t signature);
+bool get_board_settings_from_eeprom(struct eeprom_board_settings *board_cfg);