display5: Support for the emergency PAD pressing

To enter the special mode, one needs to short cut two pads with e.g. screw
driver.

After power up the SPL will execute u-boot in which proper actions will be
taken.

It is worth noting that we do not alter envs (even the BOOT_FROM variable)
and unconditionally go to recovery.

Signed-off-by: Lukasz Majewski <lukma@denx.de>

1 files changed, 22 insertions, 0 deletions

diff --git a/board/liebherr/display5/spl.c b/board/liebherr/display5/spl.c
index 0d25b0d996..551a14347d 100644
--- a/board/liebherr/display5/spl.c
+++ b/board/liebherr/display5/spl.c
@@ -16,6 +16,7 @@
 #include <asm/arch/imx-regs.h>
 #include "asm/arch/iomux.h"
 #include <asm/mach-imx/iomux-v3.h>
+#include <asm/gpio.h>
 #include <environment.h>
 #include <fsl_esdhc.h>
 #include <netdev.h>
@@ -194,10 +195,24 @@ void board_init_f(ulong dummy)
 	/* Clear the BSS. */
 	memset(__bss_start, 0, __bss_end - __bss_start);
 
+	displ5_set_iomux_misc_spl();
+
 	/* load/boot image from boot device */
 	board_init_r(NULL, 0);
 }
 
+#define EM_PAD IMX_GPIO_NR(3, 29)
+int board_check_emergency_pad(void)
+{
+	int ret;
+
+	ret = gpio_direction_input(EM_PAD);
+	if (ret)
+		return ret;
+
+	return !gpio_get_value(EM_PAD);
+}
+
 void board_boot_order(u32 *spl_boot_list)
 {
 	/* Default boot sequence SPI -> MMC */
@@ -206,6 +221,13 @@ void board_boot_order(u32 *spl_boot_list)
 	spl_boot_list[2] = BOOT_DEVICE_UART;
 	spl_boot_list[3] = BOOT_DEVICE_NONE;
 
+	/*
+	 * In case of emergency PAD pressed, we always boot
+	 * to proper u-boot and perform recovery tasks there.
+	 */
+	if (board_check_emergency_pad())
+		return;
+
 #ifdef CONFIG_SPL_ENV_SUPPORT
 	/* 'fastboot' */
 	const char *s;