R92C_HISR
rtwn_write_4(sc, R92C_HISR, 0xffffffff);
rtwn_write_4(sc, R92C_HISR, 0x00000000);
status = rtwn_pci_read_4(sc, R92C_HISR);
rtwn_pci_write_4(sc, R92C_HISR, status);