On Thu, Sep 07, 2023 at 04:39:33PM +0300, Dmitry Baryshkov wrote:
> On Thu, 7 Sept 2023 at 08:22, Varadarajan Narayanan
> <quic_varada@xxxxxxxxxxx> wrote:
> >
> > Stromer plus APSS PLL does not support dynamic frequency scaling.
> > To switch between frequencies, we have to shut down the PLL,
> > configure the L and ALPHA values and turn on again. So introduce the
> > separate set of ops for Stromer Plus PLL.
> >
> > Signed-off-by: Kathiravan T <quic_kathirav@xxxxxxxxxxx>
> > Signed-off-by: Varadarajan Narayanan <quic_varada@xxxxxxxxxxx>
> > ---
> > drivers/clk/qcom/clk-alpha-pll.c | 68 ++++++++++++++++++++++++++++++++++++++++
> > drivers/clk/qcom/clk-alpha-pll.h | 1 +
> > 2 files changed, 69 insertions(+)
> >
> > diff --git a/drivers/clk/qcom/clk-alpha-pll.c b/drivers/clk/qcom/clk-alpha-pll.c
> > index e4ef645..2ef81f7 100644
> > --- a/drivers/clk/qcom/clk-alpha-pll.c
> > +++ b/drivers/clk/qcom/clk-alpha-pll.c
> > @@ -2479,3 +2479,71 @@ const struct clk_ops clk_alpha_pll_stromer_ops = {
> > .set_rate = clk_alpha_pll_stromer_set_rate,
> > };
> > EXPORT_SYMBOL_GPL(clk_alpha_pll_stromer_ops);
> > +
> > +static int clk_alpha_pll_stromer_plus_determine_rate(struct clk_hw *hw,
> > + struct clk_rate_request *req)
> > +{
> > + struct clk_alpha_pll *pll = to_clk_alpha_pll(hw);
> > + u32 l, alpha_width = pll_alpha_width(pll);
> > + u64 a;
> > +
> > + req->rate = alpha_pll_round_rate(req->rate, req->best_parent_rate, &l,
> > + &a, alpha_width);
> > + return 0;
> > +}
>
> What is the plL_alpha_width on stromer_plus? Does
> clk_alpha_pll_stromer_determine_rate() work for you?
pll_alpha_width is 4. I tested with clk_alpha_pll_stromer_determine_rate()
and it works. Will change and post a new version.
Thanks
Varada
> > +
> > +static int clk_alpha_pll_stromer_plus_set_rate(struct clk_hw *hw,
> > + unsigned long rate,
> > + unsigned long prate)
> > +{
> > + struct clk_alpha_pll *pll = to_clk_alpha_pll(hw);
> > + u32 l, alpha_width = pll_alpha_width(pll);
> > + int ret;
> > + u64 a;
> > +
> > + rate = alpha_pll_round_rate(rate, prate, &l, &a, alpha_width);
> > +
> > + regmap_write(pll->clkr.regmap, PLL_MODE(pll), 0);
> > +
> > + /* Delay of 2 output clock ticks required until output is disabled */
> > + udelay(1);
> > +
> > + regmap_write(pll->clkr.regmap, PLL_L_VAL(pll), l);
> > +
> > + if (alpha_width > ALPHA_BITWIDTH)
> > + a <<= alpha_width - ALPHA_BITWIDTH;
> > +
> > + regmap_write(pll->clkr.regmap, PLL_ALPHA_VAL(pll), a);
> > + regmap_write(pll->clkr.regmap, PLL_ALPHA_VAL_U(pll),
> > + a >> ALPHA_BITWIDTH);
> > +
> > + regmap_write(pll->clkr.regmap, PLL_MODE(pll), PLL_BYPASSNL);
> > +
> > + /* Wait five micro seconds or more */
> > + udelay(5);
> > + regmap_update_bits(pll->clkr.regmap, PLL_MODE(pll), PLL_RESET_N,
> > + PLL_RESET_N);
> > +
> > + /* The lock time should be less than 50 micro seconds worst case */
> > + udelay(50);
> > +
> > + ret = wait_for_pll_enable_lock(pll);
> > + if (ret) {
> > + pr_err("alpha pll running in 800 MHz with source GPLL0\n");
> > + return ret;
> > + }
> > + regmap_update_bits(pll->clkr.regmap, PLL_MODE(pll), PLL_OUTCTRL,
> > + PLL_OUTCTRL);
> > +
> > + return 0;
> > +}
> > +
> > +const struct clk_ops clk_alpha_pll_stromer_plus_ops = {
> > + .enable = clk_alpha_pll_enable,
> > + .disable = clk_alpha_pll_disable,
> > + .is_enabled = clk_alpha_pll_is_enabled,
> > + .recalc_rate = clk_alpha_pll_recalc_rate,
> > + .determine_rate = clk_alpha_pll_stromer_plus_determine_rate,
> > + .set_rate = clk_alpha_pll_stromer_plus_set_rate,
> > +};
> > +EXPORT_SYMBOL_GPL(clk_alpha_pll_stromer_plus_ops);
> > diff --git a/drivers/clk/qcom/clk-alpha-pll.h b/drivers/clk/qcom/clk-alpha-pll.h
> > index e4bd863..903fbab 100644
> > --- a/drivers/clk/qcom/clk-alpha-pll.h
> > +++ b/drivers/clk/qcom/clk-alpha-pll.h
> > @@ -152,6 +152,7 @@ extern const struct clk_ops clk_alpha_pll_postdiv_ops;
> > extern const struct clk_ops clk_alpha_pll_huayra_ops;
> > extern const struct clk_ops clk_alpha_pll_postdiv_ro_ops;
> > extern const struct clk_ops clk_alpha_pll_stromer_ops;
> > +extern const struct clk_ops clk_alpha_pll_stromer_plus_ops;
> >
> > extern const struct clk_ops clk_alpha_pll_fabia_ops;
> > extern const struct clk_ops clk_alpha_pll_fixed_fabia_ops;
> > --
> > 2.7.4
> >
>
>
> --
> With best wishes
> Dmitry
