[PATCH 3/3] arm: mvebu: Espressobin: Set default value for $ethNaddr env variable

[Pali Rohár]

On Espressobin board are MAC addresses stored in U-Boot env area. Therefore
they are not present in default_environment[] array constructed at compile
time.

This change puts permanent MAC addresses into default_environment[] array
at board runtime. Espressobin board has enabled DEFAULT_ENV_IS_RW option
and therefore can modify this array.

This change ensure that 'env default -a' does not delete permanent MAC
addresses from Espressobin env storage area.

Signed-off-by: Pali Rohár <pali at kernel.org>
---
 board/Marvell/mvebu_armada-37xx/board.c | 19 +++++++++++++++++++
 include/configs/mvebu_armada-37xx.h     |  4 ++++
 2 files changed, 23 insertions(+)

diff --git a/board/Marvell/mvebu_armada-37xx/board.c b/board/Marvell/mvebu_armada-37xx/board.c
index 9297ea0f90..dabd4eefd6 100644
--- a/board/Marvell/mvebu_armada-37xx/board.c
+++ b/board/Marvell/mvebu_armada-37xx/board.c
@@ -88,6 +88,9 @@ int board_late_init(void)
 	char *ptr = (char *)&default_environment[0];
 	struct mmc *mmc_dev;
 	bool ddr4, emmc;
+	const char *mac;
+	char eth[10];
+	int i;
 
 	if (!of_machine_is_compatible("globalscale,espressobin"))
 		return 0;
@@ -96,6 +99,22 @@ int board_late_init(void)
 	while (*ptr != '\0' && *(ptr+1) != '\0') ptr++;
 	ptr += 2;
 
+	/*
+	 * Ensure that 'env default -a' does not erase permanent MAC addresses
+	 * stored in env variables: $ethaddr, $eth1addr, $eth2addr and $eth3addr
+	 */
+
+	mac = env_get("ethaddr");
+	if (mac && strlen(mac) <= 17)
+		ptr += sprintf(ptr, "ethaddr=%s", mac) + 1;
+
+	for (i = 1; i <= 3; i++) {
+		sprintf(eth, "eth%daddr", i);
+		mac = env_get(eth);
+		if (mac && strlen(mac) <= 17)
+			ptr += sprintf(ptr, "%s=%s", eth, mac) + 1;
+	}
+
 	/* If the memory controller has been configured for DDR4, we're running on v7 */
 	ddr4 = ((readl(A3700_CH0_MC_CTRL2_REG) >> A3700_MC_CTRL2_SDRAM_TYPE_OFFS)
 		& A3700_MC_CTRL2_SDRAM_TYPE_MASK) == A3700_MC_CTRL2_SDRAM_TYPE_DDR4;
diff --git a/include/configs/mvebu_armada-37xx.h b/include/configs/mvebu_armada-37xx.h
index 6df702367c..2ad4325eaf 100644
--- a/include/configs/mvebu_armada-37xx.h
+++ b/include/configs/mvebu_armada-37xx.h
@@ -94,6 +94,10 @@
 
 /* filler for default values filled by board_early_init_f() */
 #define ENV_RW_FILLER \
+	"\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0" /* for ethaddr= */ \
+	"\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0" /* for eth1addr= */ \
+	"\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0" /* for eth2addr= */ \
+	"\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0" /* for eth3addr= */ \
 	"\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0" /* for fdtfile= */ \
 	""
 
-- 
2.20.1