scsi: ufs: ufs-qcom: Limit HS-G5 Rate-A to hosts with HW version 5

Qcom UFS hosts, with HW ver 5, can only support up to HS-G5 Rate-A due to
HW limitations. If the HS-G5 PHY gear is used, update host_params->hs_rate
to Rate-A, so that the subsequent power mode changes shall stick to Rate-A.
Reviewed-by: Nitin Rawat <quic_nitirawa@quicinc.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Can Guo <quic_cang@quicinc.com>
Link: https://lore.kernel.org/r/1701520577-31163-6-git-send-email-quic_cang@quicinc.com
Tested-by: Neil Armstrong <neil.armstrong@linaro.org> # on SM8550-QRD
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/ufs/host/ufs-qcom.c

@@ -442,9 +442,25 @@ static u32 ufs_qcom_get_hs_gear(struct ufs_hba *hba)
 static int ufs_qcom_power_up_sequence(struct ufs_hba *hba)
 {
 	struct ufs_qcom_host *host = ufshcd_get_variant(hba);
+	struct ufs_host_params *host_params = &host->host_params;
 	struct phy *phy = host->generic_phy;
+	enum phy_mode mode;
 	int ret;
 
+	/*
+	 * HW ver 5 can only support up to HS-G5 Rate-A due to HW limitations.
+	 * If the HS-G5 PHY gear is used, update host_params->hs_rate to Rate-A,
+	 * so that the subsequent power mode change shall stick to Rate-A.
+	 */
+	if (host->hw_ver.major == 0x5) {
+		if (host->phy_gear == UFS_HS_G5)
+			host_params->hs_rate = PA_HS_MODE_A;
+		else
+			host_params->hs_rate = PA_HS_MODE_B;
+	}
+
+	mode = host_params->hs_rate == PA_HS_MODE_B ? PHY_MODE_UFS_HS_B : PHY_MODE_UFS_HS_A;
+
 	/* Reset UFS Host Controller and PHY */
 	ret = ufs_qcom_host_reset(hba);
 	if (ret)
@@ -459,7 +475,7 @@ static int ufs_qcom_power_up_sequence(struct ufs_hba *hba)
 		return ret;
 	}
 
-	phy_set_mode_ext(phy, PHY_MODE_UFS_HS_B, host->phy_gear);
+	phy_set_mode_ext(phy, mode, host->phy_gear);
 
 	/* power on phy - start serdes and phy's power and clocks */
 	ret = phy_power_on(phy);