SR_UXL
if ((regs->status & SR_UXL) == SR_UXL_32)
csr_write(CSR_STATUS, (tmp & ~SR_UXL) | SR_UXL_32);
(csr_read(CSR_STATUS) & SR_UXL) == SR_UXL_32;
regs->status &= ~SR_UXL;