The recent changes in drivers/gpu/drm/drm_fb_helper.c turned SDL1 support into the broken state. This library requires exporting a video options, but they was removed from kernel as useless. This is a patch for 4.19.9 kernel that reverses changes back: http://saahriktu.org/downloads/patches/linux-4.19.9_make_sdl1_working_again.patch.lzma .
Sorry, I was wrong. It's not so broken. Critical lines in SDL1 code has nothing to do with options directly. Only thing it's does is just calls the FBIOPUT_VSCREENINFO and checks returned value. This lines can be removed and all works fine.