VR_CAMCTL
CSR_WRITE_1(l, VR_CAMCTL, CAMCTL_ADDR);
CSR_WRITE_1(l, VR_CAMCTL, CAMCTL_ADDR | CAMCTL_WR);
while (--loop > 0 && (i = CSR_READ_1(l, VR_CAMCTL)) & CAMCTL_WR)
CSR_WRITE_1(l, VR_CAMCTL, CAMCTL_VBIT);
CSR_WRITE_1(l, VR_CAMCTL, 0);