dmesg | grep brcm; ls /sys/firmware/efi/efivars | grep nvram
 [    5.885228] bluetooth hci0: Direct firmware load for brcm/BCM4345C0.hcd failed with error -2
 [    5.885238] Bluetooth: hci0: BCM: Patch brcm/BCM4345C0.hcd not found
 [    8.231778] brcmfmac: brcmf_fw_alloc_request: using brcm/brcmfmac43455-sdio for chip BCM4345/6
 [    8.231899] usbcore: registered new interface driver brcmfmac
 [    8.237437] brcmfmac mmc1:0001:1: Direct firmware load for brcm/brcmfmac43455-sdio.LINX-LINX12X64.txt failed with error -2
 [    8.237468] brcmfmac mmc1:0001:1: Direct firmware load for brcm/brcmfmac43455-sdio.txt failed with error -2
 [    9.241579] brcmfmac: brcmf_sdio_htclk: HT Avail timeout (1000000): clkctl 0x50