arm: mvebu: turris_mox: add support for board rescue mode

Add necessary config options and board code to support board factory
reset / rescue mode on Turris MOX.

In order to also support invoking rescue mode from U-Boot console,
without having to press the factory reset button, put the rescue command
into `bootcmd_rescue` default environment variable. When factory reset
button is pressed, invoke rescue mode via distroboot by setting
`boot_targets` to `rescue`.

Rescue boot from console can be invoked by running
  run bootcmd_rescue

Signed-off-by: Marek Behún <marek.behun@nic.cz>
Reviewed-by: Pali Rohár <pali@kernel.org>
Reviewed-by: Stefan Roese <sr@denx.de>

diff --git a/board/CZ.NIC/turris_mox/turris_mox.c b/board/CZ.NIC/turris_mox/turris_mox.c
index 15cbf92..a78f336 100644 (file)
--- a/board/CZ.NIC/turris_mox/turris_mox.c
+++ b/board/CZ.NIC/turris_mox/turris_mox.c
@@ -10,11 +10,13 @@
 #include <asm/global_data.h>
 #include <asm/io.h>
 #include <asm/gpio.h>
+#include <button.h>
 #include <clk.h>
 #include <dm.h>
 #include <env.h>
 #include <fdt_support.h>
 #include <init.h>
+#include <led.h>
 #include <linux/delay.h>
 #include <linux/libfdt.h>
 #include <linux/string.h>
@@ -44,6 +46,8 @@
 #define SFP_GPIO_PATH  "/soc/internal-regs@d0000000/spi@10600/moxtet@1/gpio@0"
 #define PCIE_PATH      "/soc/pcie@d0070000"
 #define SFP_PATH       "/sfp"
+#define LED_PATH       "/leds/led"
+#define BUTTON_PATH    "/gpio-keys/reset"
 
 DECLARE_GLOBAL_DATA_PTR;
 
@@ -373,6 +377,71 @@ int misc_init_r(void)
        return 0;
 }
 
+static bool read_reset_button(void)
+{
+       struct udevice *button, *led;
+       int i;
+
+       if (device_get_global_by_ofnode(ofnode_path(BUTTON_PATH), &button)) {
+               printf("Cannot find reset button!\n");
+               return false;
+       }
+
+       if (device_get_global_by_ofnode(ofnode_path(LED_PATH), &led)) {
+               printf("Cannot find status LED!\n");
+               return false;
+       }
+
+       led_set_state(led, LEDST_ON);
+
+       for (i = 0; i < 21; ++i) {
+               if (button_get_state(button) != BUTTON_ON)
+                       return false;
+               if (i < 20)
+                       mdelay(50);
+       }
+
+       led_set_state(led, LEDST_OFF);
+
+       return true;
+}
+
+static void handle_reset_button(void)
+{
+       if (read_reset_button()) {
+               const char * const vars[3] = {
+                       "bootcmd",
+                       "bootcmd_rescue",
+                       "distro_bootcmd",
+               };
+
+               /*
+                * Set the above envs to their default values, in case the user
+                * managed to break them.
+                */
+               env_set_default_vars(3, (char * const *)vars, 0);
+
+               /* Ensure bootcmd_rescue is used by distroboot */
+               env_set("boot_targets", "rescue");
+
+               printf("RESET button was pressed, overwriting boot_targets!\n");
+       } else {
+               /*
+                * In case the user somehow managed to save environment with
+                * boot_targets=rescue, reset boot_targets to default value.
+                * This could happen in subsequent commands if bootcmd_rescue
+                * failed.
+                */
+               if (!strcmp(env_get("boot_targets"), "rescue")) {
+                       const char * const vars[1] = {
+                               "boot_targets",
+                       };
+
+                       env_set_default_vars(1, (char * const *)vars, 0);
+               }
+       }
+}
+
 static void mox_print_info(void)
 {
        int ret, board_version, ram_size;
@@ -543,6 +612,8 @@ int last_stage_init(void)
 
        printf("\n");
 
+       handle_reset_button();
+
        return 0;
 }
 

diff --git a/configs/turris_mox_defconfig b/configs/turris_mox_defconfig
index 75524ba..d6d37a3 100644 (file)
--- a/configs/turris_mox_defconfig
+++ b/configs/turris_mox_defconfig
@@ -23,10 +23,14 @@ CONFIG_SYS_CONSOLE_INFO_QUIET=y
 # CONFIG_DISPLAY_BOARDINFO is not set
 CONFIG_ARCH_EARLY_INIT_R=y
 CONFIG_MISC_INIT_R=y
+CONFIG_BUTTON=y
+CONFIG_BUTTON_GPIO=y
+CONFIG_CMD_BUTTON=y
 CONFIG_CMD_CLK=y
 # CONFIG_CMD_FLASH is not set
 CONFIG_CMD_GPIO=y
 CONFIG_CMD_I2C=y
+CONFIG_CMD_LED=y
 CONFIG_CMD_MMC=y
 CONFIG_CMD_PCI=y
 CONFIG_CMD_SPI=y
@@ -46,6 +50,8 @@ CONFIG_CLK=y
 CONFIG_CLK_MVEBU=y
 # CONFIG_MVEBU_GPIO is not set
 CONFIG_DM_I2C=y
+CONFIG_LED=y
+CONFIG_LED_GPIO=y
 CONFIG_MISC=y
 CONFIG_MMC_SDHCI=y
 CONFIG_MMC_SDHCI_SDMA=y

diff --git a/include/configs/turris_mox.h b/include/configs/turris_mox.h
index 51445ec..b148b16 100644 (file)
--- a/include/configs/turris_mox.h
+++ b/include/configs/turris_mox.h
@@ -75,12 +75,21 @@
 
 #include <config_distro_bootcmd.h>
 
+#define TURRIS_MOX_BOOTCMD_RESCUE \
+       "setenv bootargs \"console=ttyMV0,115200 " \
+                         "earlycon=ar3700_uart,0xd0012000\" && " \
+       "sf probe && " \
+       "sf read 0x5000000 0x190000 && " \
+       "lzmadec 0x5000000 0x5800000 && " \
+       "bootm 0x5800000"
+
 #define CONFIG_EXTRA_ENV_SETTINGS      \
        "scriptaddr=0x4d00000\0"        \
        "pxefile_addr_r=0x4e00000\0"    \
        "fdt_addr_r=0x4f00000\0"        \
        "kernel_addr_r=0x5000000\0"     \
        "ramdisk_addr_r=0x8000000\0"    \
+       "bootcmd_rescue=" TURRIS_MOX_BOOTCMD_RESCUE "\0" \
        BOOTENV
 
 #endif /* _CONFIG_TURRIS_MOX_H */