Re: [PATCH v2 3/5] phy: qcom-qmp: Add optional SW reset

[Manu Gautam]

On 12/20/2019 3:47 PM, Vinod Koul wrote:
> For V4 QMP UFS Phy, we need to assert reset bits, configure the phy and
> then deassert it, so add optional has_sw_reset flag and use that to
> configure the QPHY_SW_RESET register.
>
> Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>
> ---
>  drivers/phy/qualcomm/phy-qcom-qmp.c | 11 +++++++++++
>  1 file changed, 11 insertions(+)
>
> diff --git a/drivers/phy/qualcomm/phy-qcom-qmp.c b/drivers/phy/qualcomm/phy-qcom-qmp.c
> index 1196c85aa023..47a66d55107d 100644
> --- a/drivers/phy/qualcomm/phy-qcom-qmp.c
> +++ b/drivers/phy/qualcomm/phy-qcom-qmp.c
> @@ -168,6 +168,7 @@ static const unsigned int sdm845_ufsphy_regs_layout[] = {
>  static const unsigned int sm8150_ufsphy_regs_layout[] = {
>  	[QPHY_START_CTRL]		= QPHY_V4_PHY_START,
>  	[QPHY_PCS_READY_STATUS]		= QPHY_V4_PCS_READY_STATUS,
> +	[QPHY_SW_RESET]			= QPHY_V4_SW_RESET,
>  };
>  
>  static const struct qmp_phy_init_tbl msm8996_pcie_serdes_tbl[] = {
> @@ -1023,6 +1024,9 @@ struct qmp_phy_cfg {
>  
>  	/* true, if PCS block has no separate SW_RESET register */
>  	bool no_pcs_sw_reset;
> +
> +	/* true if sw reset needs to be invoked */
> +	bool has_sw_reset;


There is no need to add new flag. Existing code will take care of it for UFS once you
clear no_pcs_sw_reset flag.

>  };
>  
>  /**
> @@ -1391,6 +1395,7 @@ static const struct qmp_phy_cfg sm8150_ufsphy_cfg = {
>  
>  	.is_dual_lane_phy	= true,
>  	.no_pcs_sw_reset	= true,
> +	.has_sw_reset		= true,
>  };
>  
>  static void qcom_qmp_phy_configure(void __iomem *base,
> @@ -1475,6 +1480,9 @@ static int qcom_qmp_phy_com_init(struct qmp_phy *qphy)
>  			     SW_USB3PHY_RESET_MUX | SW_USB3PHY_RESET);
>  	}
>  
> +	if (cfg->has_sw_reset)
> +		qphy_setbits(pcs, cfg->regs[QPHY_SW_RESET], SW_RESET);
> +

Not needed. POR value of the bit is '1'.


>  	if (cfg->has_phy_com_ctrl)
>  		qphy_setbits(serdes, cfg->regs[QPHY_COM_POWER_DOWN_CONTROL],
>  			     SW_PWRDN);
> @@ -1651,6 +1659,9 @@ static int qcom_qmp_phy_enable(struct phy *phy)
>  	if (cfg->has_phy_dp_com_ctrl)
>  		qphy_clrbits(dp_com, QPHY_V3_DP_COM_SW_RESET, SW_RESET);
>  
> +	if (cfg->has_sw_reset)
> +		qphy_clrbits(pcs, cfg->regs[QPHY_SW_RESET], SW_RESET);
> +

There is no need to add UFS specific change here as existing PHY driver can
handle PCS based PHY sw_reset and already does it for USB and PCIe.


>  	/* start SerDes and Phy-Coding-Sublayer */
>  	qphy_setbits(pcs, cfg->regs[QPHY_START_CTRL], cfg->start_ctrl);
>  

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