[PATCH 08/22] sandbox: Add work-around for SDL2 display

[Heinrich Schuchardt]

On 7/6/21 12:32 AM, Simon Glass wrote:
> At present the display does not show on some machines, e.g. Ubunutu
> 20.04 but the reason is unknown. Add a work-around until this can be
> determined.

I am running Ubuntu 20.04 and

     ./u-boot -T -l

shows the graphical console for sandbox_defconfig.

Please, provide more detail on how to reproduce the issue on Ubuntu Hirsute.

Best regards

Heinrich

>
> Also include more error checking just in case.
>
> Signed-off-by: Simon Glass <sjg at chromium.org>
> ---
>
>   arch/sandbox/cpu/sdl.c | 23 ++++++++++++++++++++++-
>   1 file changed, 22 insertions(+), 1 deletion(-)
>
> diff --git a/arch/sandbox/cpu/sdl.c b/arch/sandbox/cpu/sdl.c
> index 8102649be3a..e2649494818 100644
> --- a/arch/sandbox/cpu/sdl.c
> +++ b/arch/sandbox/cpu/sdl.c
> @@ -164,8 +164,29 @@ int sandbox_sdl_init_display(int width, int height, int log2_bpp,
>
>   int sandbox_sdl_sync(void *lcd_base)
>   {
> +	struct SDL_Rect rect;
> +	int ret;
> +
> +	if (!sdl.texture)
> +		return 0;
> +	SDL_RenderClear(sdl.renderer);
>   	SDL_UpdateTexture(sdl.texture, NULL, lcd_base, sdl.pitch);
> -	SDL_RenderCopy(sdl.renderer, sdl.texture, NULL, NULL);
> +	ret = SDL_RenderCopy(sdl.renderer, sdl.texture, NULL, NULL);
> +	if (ret) {
> +		printf("SDL copy %d: %s\n", ret, SDL_GetError());
> +		return -EIO;
> +	}
> +
> +	/*
> +	 * On some machines this does not appear. Draw an empty rectangle which
> +	 * seems to fix that.
> +	 */
> +	rect.x = 0;
> +	rect.y = 0;
> +	rect.w = 0;
> +	rect.h = 0;
> +	SDL_RenderDrawRect(sdl.renderer, &rect);
> +
>   	SDL_RenderPresent(sdl.renderer);
>   	sandbox_sdl_poll_events();
>
>