ARM: stm32: Read values from M24256 write-lockable page on STM32MP13xx DHCOR

The STM32MP13xx DHCOR SoM is populated with M24256 EEPROM that contains
an additional write-lockable page called ID page, which is populated with
a structure containing ethernet MAC addresses, DH item number and DH serial
number.

Read out the MAC address from the WL page between higher priority SoC fuses
and lower priority plain EEPROM storage area. Read out the DH item and serial
numbers and set environment variables accordingly.

Signed-off-by: Marek Vasut <[email protected]>
Reviewed-by: Patrice Chotard <[email protected]>

2 files changed, 43 insertions, 9 deletions

diff --git a/arch/arm/dts/stm32mp13xx-dhcor-u-boot.dtsi b/arch/arm/dts/stm32mp13xx-dhcor-u-boot.dtsi
index 5ca0258e3ff..bedb7c600d5 100644
--- a/arch/arm/dts/stm32mp13xx-dhcor-u-boot.dtsi
+++ b/arch/arm/dts/stm32mp13xx-dhcor-u-boot.dtsi
@@ -10,6 +10,7 @@
 / {
 	aliases {
 		eeprom0 = &eeprom0;
+		eeprom0wl = &eeprom0wl;
 	};
 
 	config {
diff --git a/board/dhelectronics/dh_stm32mp1/board.c b/board/dhelectronics/dh_stm32mp1/board.c
index a9b1a0f2c34..065d2f338c2 100644
--- a/board/dhelectronics/dh_stm32mp1/board.c
+++ b/board/dhelectronics/dh_stm32mp1/board.c
@@ -119,7 +119,7 @@ static bool dh_stm32_mac_is_in_ks8851(void)
 	return false;
 }
 
-static int dh_stm32_setup_ethaddr(void)
+static int dh_stm32_setup_ethaddr(struct eeprom_id_page *eip)
 {
 	unsigned char enetaddr[6];
 
@@ -129,13 +129,19 @@ static int dh_stm32_setup_ethaddr(void)
 	if (dh_get_mac_is_enabled("ethernet0"))
 		return 0;
 
+	if (!dh_get_value_from_eeprom_buffer(DH_MAC0, enetaddr, sizeof(enetaddr), eip))
+		goto out;
+
 	if (!dh_get_mac_from_eeprom(enetaddr, "eeprom0"))
-		return eth_env_set_enetaddr("ethaddr", enetaddr);
+		goto out;
 
 	return -ENXIO;
+
+out:
+	return eth_env_set_enetaddr("ethaddr", enetaddr);
 }
 
-static int dh_stm32_setup_eth1addr(void)
+static int dh_stm32_setup_eth1addr(struct eeprom_id_page *eip)
 {
 	unsigned char enetaddr[6];
 
@@ -148,20 +154,47 @@ static int dh_stm32_setup_eth1addr(void)
 	if (dh_stm32_mac_is_in_ks8851())
 		return 0;
 
-	if (!dh_get_mac_from_eeprom(enetaddr, "eeprom0")) {
-		enetaddr[5]++;
-		return eth_env_set_enetaddr("eth1addr", enetaddr);
-	}
+	if (!dh_get_value_from_eeprom_buffer(DH_MAC1, enetaddr, sizeof(enetaddr), eip))
+		goto out;
+
+	if (!dh_get_mac_from_eeprom(enetaddr, "eeprom0"))
+		goto increment_out;
 
 	return -ENXIO;
+
+increment_out:
+	enetaddr[5]++;
+
+out:
+	return eth_env_set_enetaddr("eth1addr", enetaddr);
 }
 
 int setup_mac_address(void)
 {
-	if (dh_stm32_setup_ethaddr())
+	u8 eeprom_buffer[DH_EEPROM_ID_PAGE_MAX_SIZE] = { 0 };
+	struct eeprom_id_page *eip = (struct eeprom_id_page *)eeprom_buffer;
+	int ret;
+
+	ret = dh_read_eeprom_id_page(eeprom_buffer, "eeprom0wl");
+	if (ret) {
+		/*
+		 * The EEPROM ID page is available on SoM rev. 200 and greater.
+		 * For SoM rev. 100 the return value will be -ENODEV. Suppress
+		 * the error message for that, because the absence cannot be
+		 * treated as an error.
+		 */
+		if (ret != -ENODEV)
+			printf("%s: Cannot read valid data from EEPROM ID page! ret = %d\n",
+			       __func__, ret);
+		eip = NULL;
+	} else {
+		dh_add_item_number_and_serial_to_env(eip);
+	}
+
+	if (dh_stm32_setup_ethaddr(eip))
 		log_err("%s: Unable to setup ethaddr!\n", __func__);
 
-	if (dh_stm32_setup_eth1addr())
+	if (dh_stm32_setup_eth1addr(eip))
 		log_err("%s: Unable to setup eth1addr!\n", __func__);
 
 	return 0;