Patch description: There are 2 patches, patch 1 would add a bmp decoder to enable seabios show bmp file, patch 2 will make the splash time configurable. Main purpose of this patch is: 1 Enable seabios showing a logo picture when start up without menu option. 2 Added a bmp showing module to show 24bpp bmp file as an option, for better visual effect than old jpeg decoder. 3 Make the showing time configurable by qemu, when it equals 0, directly boot up. 4 added a function to adjust data format, both used by jpeg decoder and bmp module.
Currently I passed the variable Splash_time from a romfile, named "qemu_extra_params_fw.cfg", I think more variable could be simply packed inside this file in the future, not only for the splash_time value.