Add tb_menu command

This command allows creating *imperatively* dynamic menus. This is done
through building the menus with commands, rather than through hardly
dynamic numbered environment variables.

This uses PDCurses for *more correct* TUI interfaces. Though the
approach could be used without; changing the existing bootmenu to an
imperative approach could be done too.

Using PDCurses, though, allows for more complex interactions to happen
in a more standard way. While curses are named appropriately, from the
cursing of developers using it, it had undeniable advantages compared
to manually doing the hard work of building text-based interfaces.

This first draft is sufficient for the desired goals. This is probably
not the final form of the menu.

Author: samueldr

cmd/Kconfig

@@ -2849,3 +2849,5 @@ config CMD_MESON
 	help
 	  Enable useful commands for the Meson Soc family developed by Amlogic Inc.
 endmenu
+
+source cmd/tow-boot/Kconfig

cmd/Makefile

@@ -281,3 +281,6 @@ $(obj)/license_data_size.h: $(srctree)/Licenses/gpl-2.0.txt FORCE
 	$(call filechk,data_size)
 
 CFLAGS_ethsw.o := -Wno-enum-conversion
+
+# Always included, individual commands can be toggled.
+obj-y += tow-boot/

cmd/tow-boot/Kconfig

@@ -0,0 +1,43 @@
+menu "Tow-Boot additional commands"
+
+config TOW_BOOT_MENU
+	bool "Enable Tow-Boot menu commands"
+	default n
+	select PDCURSES
+	select CMD_CLS
+	help
+	  Add support for curses menu interface.
+
+config TOW_BOOT_MENU_CTRL_C_EXITS
+	bool "CTRL+C exits the menu"
+	default n
+	depends on TOW_BOOT_MENU
+
+endmenu
+
+menu "Tow-Boot menu storage name configuration"
+
+config TOW_BOOT_MMC0_NAME
+	string "MMC0 user-friendly name"
+	default "SD" if ARCH_SUNXI
+	default "SD" if MESON_G12A || MESON_GXL
+	default "eMMC"
+	help
+	  Name used in the interface for MMC0
+
+config TOW_BOOT_MMC1_NAME
+	string "MMC1 user-friendly name"
+	default "eMMC" if ARCH_SUNXI
+	default "eMMC" if MESON_G12A || MESON_GXL
+	default "SD"
+	help
+	  Name used in the interface for MMC1
+
+config TOW_BOOT_MMC2_NAME
+	string "MMC2 user-friendly name"
+	default "(sdio)" if MESON_G12A || MESON_GXL
+	default "(Unused)"
+	help
+	  Name used in the interface for MMC2
+
+endmenu

cmd/tow-boot/Makefile

@@ -0,0 +1,17 @@
+# SPDX-License-Identifier: GPL-2.0+
+#
+# (C) Copyright 2021 Samuel Dionne-Riel
+#
+
+# This file is always included.
+
+subdir-ccflags-y := -I$(srctree)/lib/PDCursesMod/include
+subdir-ccflags-y += -I$(srctree)/$(src)/include
+
+obj- += dummy.o
+
+ifndef CONFIG_SPL_BUILD
+
+obj-$(CONFIG_TOW_BOOT_MENU) += tow-boot_menu.o
+
+endif