logx
x = logx(x,y);
case 1: val = logx(val,FIX1LOGE); break;
case 2: val = logx(val,FIX1LOG10); break;
case 3: val = logx(val,FIX1LOG2); break;
#define MUSB2_VAL_FIFOSZ(logx) ((logx) - 3)