#define MI_INSTR(op, flag)	(((op) << 23) | (flag))
#define MI_NOOP				MI_INSTR(0, 0)
#define MI_NOOP_ID(id)		MI_INSTR(0, (1<<22|(id)))

enum {
	XY_COLOR_BLT	= 0x50,
};

typedef struct Ring Ring;
struct Ring {
	u32int *mmio;
	void *va;
	uintptr gtta;
};

int ringinit(Ring *r, u32int *mmio, void *va, uintptr gtta);
int ringstart(Ring *r);
int ringstop(Ring *r);
int ringbusy(Ring *r);