Re: [PATCH 06/10] phy: qcom-ipq806x-usb: fix the PHY_PARAM_CTRL1 field masks

[Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>]

On 8/10/26 1:42 PM, Dmitry Baryshkov wrote:
> Each of the PHY_PARAM_CTRL1 field masks extends one bit below its
> documented field: TX_FULL_SWING [26:20] is coded as GENMASK(26, 19),
> TX_DEEMPH_6DB [19:14] as GENMASK(19, 13), TX_DEEMPH_3_5DB [13:8] as
> GENMASK(13, 7) and LOS_BIAS [7:3] as GENMASK(7, 2). Also, the field
> described as LOS_BIAS in reality is called LOS_LEVEL. FIELD_PREP against
> these masks places every value one bit short of its field, so the
> programmed swing/de-emphasis/LOS parameters land shifted and the
> neighbouring fields are corrupted; the masked write-readback in the SS
> PHY init reports 'write: ... to QSCRATCH: 4 FAILED'.
> 
> Align the masks with the documented field positions.
> 
> Fixes: ef19b117b834 ("phy: qualcomm: add qcom ipq806x dwc usb phy driver")
> Assisted-by: Claude:claude-fable-5
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
> ---

[...]

> @@ -436,7 +440,8 @@ static int qcom_ipq806x_usb_ss_phy_init(struct phy *phy)
>  	data |= PHY_PARAM_CTRL1_TX_FULL_SWING(0x6e) |
>  		PHY_PARAM_CTRL1_TX_DEEMPH_6DB(0x20) |
>  		PHY_PARAM_CTRL1_TX_DEEMPH_3_5DB(phy_dwc3->tx_deamp_3_5db) |
> -		PHY_PARAM_CTRL1_LOS_BIAS(0x9);
> +		PHY_PARAM_CTRL1_LOS_LEVEL(0x9) |
> +		PHY_PARAM_CTRL1_LOS_BIAS(0x0);

lgtm except the POR value of BIAS is 2 on 8974 and 0 on ipq806x

Konrad