Expects: AX    4f04H
CX    bit flags indicate which states to save/restore
DL    SubFn number:  00H = Get save-state buffer size
01H = Save SuperVGA state
02H = Restore SuperVGA state
ES:BX addr of buffer (subfns 01H and 02H only)
                                                                  
Returns: AX    VESA status: AH=0 means successful (else failed)
AL=4fH means function supported
BX    size of save-state buffer in 64-byte blocks (subfn 00H only)
                                                                  
Info: Use this function to save the current state of the SuperVGA
system and to later restore that state.

CX describes what you want to save or restore as bit flags:
1
 5   4 3 2 1 0 
 0...0 s c b h 
                bit  mask
           0: 01H save/restore video hardware state
           1: 02H save/restore video BIOS data state
           2: 04H save/restore DAC state; color regs
           3: 08H save/restore entire SuperVGA state

Notes:   To use this function: first decide what info you need to save
and set the bits of CX and set DL to 00H to see how much memory
you'll need.  Then allocate a buffer of the needed size (it is
BX * 64 bytes lone).  Set ES:BX to point to the buffer and use
DL=01H to save the info into the buffer.

  The layout of the return information at ES:BX is not documented
and will be OEM-dependent.

See Also: SVGA
- -

INT 10H 4f04H - Save/Restore SuperVGA State