[PATCH v5] phy: qcom-qmp-ufs: provide symbol clocks

[Dmitry Baryshkov]

On Fri, 28 Oct 2022 at 16:40, Bjorn Andersson <andersson at kernel.org> wrote:
>
> On Fri, Oct 28, 2022 at 03:51:48PM +0300, Dmitry Baryshkov wrote:
> > Register three UFS symbol clocks (ufs_rx_symbol_0_clk_src,
> > ufs_rx_symbol_1_clk_src ufs_tx_symbol_0_clk_src). Register OF clock
> > provider to let other devices link these clocks through the DT.
> >
> > Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov at linaro.org>
> > ---
> >
> > Changes since v4:
> > - Rebased, dropping merged clk patches
> > - Fix whitespace errors
> > - Add linebreaks to fit into 100 chars limit
> >
> > ---
> >  drivers/phy/qualcomm/phy-qcom-qmp-ufs.c | 61 +++++++++++++++++++++++++
> >  1 file changed, 61 insertions(+)
> >
> > diff --git a/drivers/phy/qualcomm/phy-qcom-qmp-ufs.c b/drivers/phy/qualcomm/phy-qcom-qmp-ufs.c
> > index e28c45ab74ea..f60e29c68c26 100644
> > --- a/drivers/phy/qualcomm/phy-qcom-qmp-ufs.c
> > +++ b/drivers/phy/qualcomm/phy-qcom-qmp-ufs.c
> > @@ -1067,6 +1067,60 @@ static int qmp_ufs_clk_init(struct device *dev, const struct qmp_phy_cfg *cfg)
> >       return devm_clk_bulk_get(dev, num, qmp->clks);
> >  }
> >
> > +static void phy_clk_release_provider(void *res)
> > +{
> > +     of_clk_del_provider(res);
> > +}
> > +
> > +#define UFS_SYMBOL_CLOCKS 3
> > +
> > +static int phy_symbols_clk_register(struct qcom_qmp *qmp, struct device_node *np)
> > +{
> > +     struct clk_hw_onecell_data *clk_data;
> > +     struct clk_hw *hw;
> > +     char name[64];
> > +     int ret;
> > +
> > +     clk_data = devm_kzalloc(qmp->dev,
> > +                             struct_size(clk_data, hws, UFS_SYMBOL_CLOCKS),
> > +                             GFP_KERNEL);
> > +     if (!clk_data)
> > +             return -ENOMEM;
> > +
> > +     clk_data->num = UFS_SYMBOL_CLOCKS;
> > +
> > +     snprintf(name, sizeof(name), "%s::rx_symbol_0", dev_name(qmp->dev));
> > +     hw = devm_clk_hw_register_fixed_rate(qmp->dev, name, NULL, 0, 0);
>
> Wouldn't it be desirable to provide a non-zero frequency for these
> clocks?

Is there a stable frequency that we can provide here? If I remember
correctly from my tests, UFS symbol frequencies vary depending on the
workload (but I might be mistaken here).




-- 
With best wishes
Dmitry