[U-Boot] [PATCH u-boot-marvell v3 14/17] arm: mvebu: turris_omnia: add RESET button handling

[Marek Behún]

There is a Factory RESET button on the back side of the Turris Omnia
router. When user presses this button before powering the device up and
keeps it pressed, the microcontroller prevents the main CPU from booting
and counts how long the RESET button is being pressed (and indicates
this by lighting up front LEDs).

The idea behind this is that the user can boot the device into several
Factory RESET modes.

This patch adds support for U-Boot to read into which Factory RESET mode
the user booted the device. The value is an integer stored into the
omnia_reset environment variable. It is 0 if the button was not pressed
at all during power up, otherwise it is the number identifying the
Factory RESET mode.

This patch also changes bootcmd to a special hardcoded value if Factory
RESET button was pressed during device powerup. This special bootcmd
value sets the colors of all the LEDs on the front panel to green and
then tries to load the rescue image from the SPI flash memory and boot
it.

Signed-off-by: Marek Behún <marek.behun at nic.cz>
---
 arch/arm/mach-mvebu/Kconfig              |  1 +
 board/CZ.NIC/turris_omnia/turris_omnia.c | 38 ++++++++++++++++++++++++
 2 files changed, 39 insertions(+)

diff --git a/arch/arm/mach-mvebu/Kconfig b/arch/arm/mach-mvebu/Kconfig
index fc29c3b084..a832e1dc8c 100644
--- a/arch/arm/mach-mvebu/Kconfig
+++ b/arch/arm/mach-mvebu/Kconfig
@@ -116,6 +116,7 @@ config TARGET_DB_88F6820_AMC
 config TARGET_TURRIS_OMNIA
 	bool "Support Turris Omnia"
 	select 88F6820
+	select BOARD_LATE_INIT
 	select DM_I2C
 	select I2C_MUX
 	select I2C_MUX_PCA954x
diff --git a/board/CZ.NIC/turris_omnia/turris_omnia.c b/board/CZ.NIC/turris_omnia/turris_omnia.c
index af43ee23d9..ad6e29021e 100644
--- a/board/CZ.NIC/turris_omnia/turris_omnia.c
+++ b/board/CZ.NIC/turris_omnia/turris_omnia.c
@@ -328,6 +328,43 @@ static int set_regdomain(void)
 	printf("Regdomain set to %s\n", rd);
 	return env_set("regdomain", rd);
 }
+
+/*
+ * default factory reset bootcommand on Omnia first sets all the front LEDs
+ * to green and then tries to load the rescue image from SPI flash memory and
+ * boot it
+ */
+#define OMNIA_FACTORY_RESET_BOOTCMD \
+	"i2c dev 2; " \
+	"i2c mw 0x2a.1 0x3 0x1c 1; " \
+	"i2c mw 0x2a.1 0x4 0x1c 1; " \
+	"mw.l 0x01000000 0x00ff000c; " \
+	"i2c write 0x01000000 0x2a.1 0x5 4 -s; " \
+	"setenv bootargs \"$bootargs omniarescue=$omnia_reset\"; " \
+	"sf probe; " \
+	"sf read 0x1000000 0x100000 0x700000; " \
+	"bootm 0x1000000; " \
+	"bootz 0x1000000"
+
+static void handle_reset_button(void)
+{
+	int ret;
+	u8 reset_status;
+
+	ret = omnia_mcu_read(CMD_GET_RESET, &reset_status, 1);
+	if (ret) {
+		printf("omnia_mcu_read failed: %i, reset status unknown!\n",
+		       ret);
+		return;
+	}
+
+	env_set_ulong("omnia_reset", reset_status);
+
+	if (reset_status) {
+		printf("RESET button was pressed, overwriting bootcmd!\n");
+		env_set("bootcmd", OMNIA_FACTORY_RESET_BOOTCMD);
+	}
+}
 #endif
 
 int board_early_init_f(void)
@@ -373,6 +410,7 @@ int board_late_init(void)
 {
 #ifndef CONFIG_SPL_BUILD
 	set_regdomain();
+	handle_reset_button();
 #endif
 
 	return 0;
-- 
2.21.0