diff options
| -rw-r--r-- | lib/efi_loader/Kconfig | 9 | ||||
| -rw-r--r-- | lib/efi_loader/efi_console.c | 13 |
2 files changed, 21 insertions, 1 deletions
diff --git a/lib/efi_loader/Kconfig b/lib/efi_loader/Kconfig index b630d88ef9e..c56904afc2e 100644 --- a/lib/efi_loader/Kconfig +++ b/lib/efi_loader/Kconfig @@ -124,6 +124,15 @@ config EFI_SET_TIME Provide the SetTime() runtime service at boottime. This service can be used by an EFI application to adjust the real time clock. +config EFI_SCROLL_ON_CLEAR_SCREEN + bool "Avoid overwriting previous output on clear screen" + help + Instead of erasing the screen content when the console screen should + be cleared, emit blank new lines so that previous output is scrolled + out of sight rather than overwritten. On serial consoles this allows + to capture complete boot logs (except for interactive menus etc.) + and can ease debugging related issues. + config EFI_HAVE_CAPSULE_SUPPORT bool diff --git a/lib/efi_loader/efi_console.c b/lib/efi_loader/efi_console.c index 9316995073e..1ed8c7aa36e 100644 --- a/lib/efi_loader/efi_console.c +++ b/lib/efi_loader/efi_console.c @@ -461,10 +461,21 @@ static efi_status_t EFIAPI efi_cout_set_attribute( } /** - * efi_cout_clear_screen() - clear screen + * efi_clear_screen() - clear screen */ static void efi_clear_screen(void) { + if (CONFIG_IS_ENABLED(EFI_SCROLL_ON_CLEAR_SCREEN)) { + unsigned int row, screen_rows, screen_columns; + + /* Avoid overwriting previous outputs on streaming consoles */ + screen_rows = efi_cout_modes[efi_con_mode.mode].rows; + screen_columns = efi_cout_modes[efi_con_mode.mode].columns; + printf(ESC "[%u;%uH", screen_rows, screen_columns); + for (row = 1; row < screen_rows; row++) + printf("\n"); + } + /* * The Linux console wants both a clear and a home command. The video * uclass does not support <ESC>[H without coordinates, yet. |