Start from HW ver 5, a spare register in UFS host controller is added and
used to indicate the UFS device version. The spare register is populated by
bootloader for now, but in future it will be populated by HW automatically
during link startup with its best efforts in any boot stage prior to Linux.

During host driver init, read the spare register, if it is not populated
with a UFS device version, go ahead with the dual init mechanism. If a UFS
device version is in there, use the UFS device version together with host
controller's HW version to decide the proper PHY gear which should be used
to configure the UFS PHY without going through the second init.
Signed-off-by: Bao D. Nguyen <quic_nguyenb@quicinc.com>
Signed-off-by: Can Guo <quic_cang@quicinc.com>
Link: https://lore.kernel.org/r/1701520577-31163-9-git-send-email-quic_cang@quicinc.comReviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Nitin Rawat <quic_nitirawa@quicinc.com>
Tested-by: Neil Armstrong <neil.armstrong@linaro.org> # on SM8550-QRD
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>