#define VGA_OFFSET (-0x3c0)
#define BLT_OFFSET (0x100)

#define CIRRUS_MMIO_BLTBGCOLOR        0x00	// dword
#define CIRRUS_MMIO_BLTFGCOLOR        0x04	// dword
#define CIRRUS_MMIO_BLTWIDTH          0x08	// word
#define CIRRUS_MMIO_BLTHEIGHT         0x0a	// word
#define CIRRUS_MMIO_BLTDESTPITCH      0x0c	// word
#define CIRRUS_MMIO_BLTSRCPITCH       0x0e	// word
#define CIRRUS_MMIO_BLTDESTADDR       0x10	// dword
#define CIRRUS_MMIO_BLTSRCADDR        0x14	// dword
#define CIRRUS_MMIO_BLTWRITEMASK      0x17	// byte
#define CIRRUS_MMIO_BLTMODE           0x18	// byte
#define CIRRUS_MMIO_BLTROP            0x1a	// byte
#define CIRRUS_MMIO_BLTMODEEXT        0x1b	// byte
#define CIRRUS_MMIO_BLTSTATUS         0x40	// byte

#define CIRRUS_BLT_BUSY                 0x01
#define CIRRUS_BLT_START                0x02
#define CIRRUS_BLT_RESET                0x04

#define CIRRUS_BLTMODE_BACKWARDS        0x01
#define CIRRUS_BLTMODE_MEMSYSDEST       0x02
#define CIRRUS_BLTMODE_MEMSYSSRC        0x04
#define CIRRUS_BLTMODE_TRANSPARENTCOMP  0x08
#define CIRRUS_BLTMODE_PATTERNCOPY      0x40
#define CIRRUS_BLTMODE_COLOREXPAND      0x80
#define CIRRUS_BLTMODE_PIXELWIDTHMASK   0x30
#define CIRRUS_BLTMODE_PIXELWIDTH8      0x00
#define CIRRUS_BLTMODE_PIXELWIDTH16     0x10
#define CIRRUS_BLTMODE_PIXELWIDTH24     0x20
#define CIRRUS_BLTMODE_PIXELWIDTH32     0x30

#define CIRRUS_ROP_0                    0x00
#define CIRRUS_ROP_SRC_AND_DST          0x05
#define CIRRUS_ROP_NOP                  0x06
#define CIRRUS_ROP_SRC_AND_NOTDST       0x09
#define CIRRUS_ROP_NOTDST               0x0b
#define CIRRUS_ROP_SRC                  0x0d
#define CIRRUS_ROP_1                    0x0e
#define CIRRUS_ROP_NOTSRC_AND_DST       0x50
#define CIRRUS_ROP_SRC_XOR_DST          0x59
#define CIRRUS_ROP_SRC_OR_DST           0x6d
#define CIRRUS_ROP_NOTSRC_OR_NOTDST     0x90
#define CIRRUS_ROP_SRC_NOTXOR_DST       0x95
#define CIRRUS_ROP_SRC_OR_NOTDST        0xad
#define CIRRUS_ROP_NOTSRC               0xd0
#define CIRRUS_ROP_NOTSRC_OR_DST        0xd6
#define CIRRUS_ROP_NOTSRC_AND_NOTDST    0xda

void cirrus_setmode(volatile uint8_t *mmio);