On Tue, Oct 29, 2024 at 05:47:10PM +0800, Weijie Gao wrote:
> It's observed that the bootmenu on a serial console sometimes
> incorrectly quitted with superfluous characters filled to command
> line input:
>
> > *** U-Boot Boot Menu ***
> >
> > 1. Startup system (Default)
> > 2. Upgrade firmware
> > 3. Upgrade ATF BL2
> > 4. Upgrade ATF FIP
> > 5. Load image
> > 0. U-Boot console
> >
> >
> > Press UP/DOWN to move, ENTER to select, ESC to quit
> >MT7988> [B
>
> Analysis shows it was caused by the wrong logic of bootmenu_loop:
>
> At first the bootmenu_loop received the first ESC char correctly.
>
> However, during the second call to bootmenu_loop, there's no data
> in the UART Rx FIFO. Due to the low baudrate, the second char of
> the down array key sequence hasn't be fully received.
>
> But bootmenu_loop just did a mdelay(10), and then treated it as a
> single ESC key press event. It didn't even try tstc() again after
> the 10ms timeout.
>
> This patch fixes this issue by letting bootmenu_loop check tstc()
> twice.
>
> Tested-By: E Shattow <luc...@gmail.com>
> Signed-off-by: Weijie Gao <weijie....@mediatek.com>
Reviewed-by: Daniel Golle <dan...@makrotopia.org>
Tested-by: Daniel Golle <dan...@makrotopia.org>
Together with 2/3 and 3/3 this now avoids dropping into the U-Boot shell
as long as the menu is short enough. In case of menus with 8 entries of
more I still manage to drop into shell when holding the arrow down key
before the last item has been reached.
That being said, it's already a very big improvement that this now only
happens when holding down a button traversing over a menu with a high
number of items.
> ---
> common/menu.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/common/menu.c b/common/menu.c
> index 8cc9bf06d9c..48ab7f0f398 100644
> --- a/common/menu.c
> +++ b/common/menu.c
> @@ -525,14 +525,15 @@ enum bootmenu_key bootmenu_loop(struct bootmenu_data
> *menu,
> struct cli_ch_state *cch)
> {
> enum bootmenu_key key;
> - int c;
> + int c, errchar = 0;
>
> c = cli_ch_process(cch, 0);
> if (!c) {
> while (!c && !tstc()) {
> schedule();
> mdelay(10);
> - c = cli_ch_process(cch, -ETIMEDOUT);
> + c = cli_ch_process(cch, errchar);
> + errchar = -ETIMEDOUT;
> }
> if (!c) {
> c = getchar();
> --
> 2.45.2
>
