As far as I know, QEMU should be able to tell SeaBIOS the exact geometry to use (eg, via qemu -hdachs c,h,s[,t] option). If you're not getting the expected behavior, be sure to include the seabios log file - see: https://www.seabios.org/Debugging
Here is geometry when I have with patched bios (Windows boot): drive 0x000f57f0: PCHS=16383/16/63 translation=lba LCHS=1024/255/32 s=143305920
Here is geometry I have with original Seabios (boot fails): drive 0x000f0bd0: PCHS=16383/16/63 translation=lba LCHS=1024/255/63 s=143305920
Qemu limits what we can specify in CHS to 16383, 16 and 63 respectively and I don't see any combinations which will perform necessary translation from PCHS=16383/16/63 to LCHS=1024/255/32.
I have attached 4 logs:
serial-no-chs.log - launch Qemu with original Seabios. No manual CHS modifications. serial-1024-16-32.log - launch Qemu with original Seabios. Manual CHS(1024, 16, 32). serial-8192-16-32.log - launch Qemu with original Seabios. Manual CHS(8192, 16, 32). serial-patched-bios.log - launch Qemu with PATCHED Seabios. No manual CHS modification.
-- +380979184774 Mykola Ivanets