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Diffstat (limited to 'doc/usage/cmd/bootmenu.rst')
| -rw-r--r-- | doc/usage/cmd/bootmenu.rst | 74 |
1 files changed, 74 insertions, 0 deletions
diff --git a/doc/usage/cmd/bootmenu.rst b/doc/usage/cmd/bootmenu.rst index 9430f8c9aa..cb3c8d2f93 100644 --- a/doc/usage/cmd/bootmenu.rst +++ b/doc/usage/cmd/bootmenu.rst @@ -4,6 +4,15 @@ bootmenu command ================ +Synopsis +-------- +:: + + bootmenu [delay] + +Description +----------- + The "bootmenu" command uses U-Boot menu interfaces and provides a simple mechanism for creating menus with different boot items. The cursor keys "Up" and "Down" are used for navigation through @@ -79,6 +88,55 @@ The above example will be rendered as below:: The selected menu entry will be highlighted - it will have inverted background and text colors. +UEFI boot variable enumeration +'''''''''''''''''''''''''''''' +If enabled, the bootmenu command will automatically generate and add +UEFI-related boot menu entries for the following items. + + * possible bootable media with default file names + * user-defined UEFI boot options + +The bootmenu automatically enumerates the possible bootable +media devices supporting EFI_SIMPLE_FILE_SYSTEM_PROTOCOL. +This auto generated entry is named as "<interface> <devnum>:<part>" format. +(e.g. "usb 0:1") + +The bootmenu displays the UEFI-related menu entries in order of "BootOrder". +When the user selects the UEFI boot menu entry, the bootmenu sets +the selected boot variable index to "BootNext" without non-volatile attribute, +then call the uefi boot manager with the command "bootefi bootmgr". + +Example bootmenu is as below:: + + *** U-Boot Boot Menu *** + + mmc 0:1 + mmc 0:2 + debian + nvme 0:1 + ubuntu + nvme 0:2 + usb 0:2 + U-Boot console + +Default behavior when user exits from the bootmenu +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +User can exit from bootmenu by selecting the last entry +"U-Boot console"/"Quit" or ESC/CTRL+C key. + +When the CONFIG_BOOTMENU_DISABLE_UBOOT_CONSOLE is disabled, +user exits from the bootmenu and returns to the U-Boot console. + +When the CONFIG_BOOTMENU_DISABLE_UBOOT_CONSOLE is enabled, user can not +enter the U-Boot console. When the user exits from the bootmenu, +the bootmenu invokes the following default behavior. + + * if CONFIG_CMD_BOOTEFI_BOOTMGR is enabled, execute "bootefi bootmgr" command + * "bootefi bootmgr" fails or is not enabled, then execute "run bootcmd" command. + +Configuration +------------- + The "bootmenu" command is enabled by:: CONFIG_CMD_BOOTMENU=y @@ -88,3 +146,19 @@ To run the bootmenu at startup add these additional settings:: CONFIG_AUTOBOOT_KEYED=y CONFIG_BOOTDELAY=30 CONFIG_AUTOBOOT_MENU_SHOW=y + +UEFI boot variable enumeration is enabled by:: + + CONFIG_CMD_BOOTEFI_BOOTMGR=y + +To improve the product security, entering U-Boot console from bootmenu +can be disabled by:: + + CONFIG_BOOTMENU_DISABLE_UBOOT_CONSOLE=y + +To scan the discoverable devices connected to the buses such as +USB and PCIe prior to bootmenu showing up, CONFIG_PREBOOT can be +used to run the command before showing the bootmenu, i.e.:: + + CONFIG_USE_PREBOOT=y + CONFIG_PREBOOT="pci enum; usb start; scsi scan; nvme scan; virtio scan" |