Re: [PATCH v4 09/20] clk: tegra: pll: Add logic for SS

From: Benson Leung
Date: Mon May 04 2015 - 19:12:08 EST


On Mon, May 4, 2015 at 9:37 AM, Rhyland Klein <rklein@xxxxxxxxxx> wrote:
> From: Bill Huang <bilhuang@xxxxxxxxxx>
>
> Add some logic for Spread Spectrum control. It is used in conjuncture
> with SDM fractional dividers. SSC has to be disabled when we configure
> the divider settings.
>
> Signed-off-by: Bill Huang <bilhuang@xxxxxxxxxx>
> ---
> drivers/clk/tegra/clk-pll.c | 25 ++++++++++++++++++++++++-
> drivers/clk/tegra/clk.h | 2 ++
> 2 files changed, 26 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/clk/tegra/clk-pll.c b/drivers/clk/tegra/clk-pll.c
> index c64b75185d6b..2a559408cee1 100644
> --- a/drivers/clk/tegra/clk-pll.c
> +++ b/drivers/clk/tegra/clk-pll.c
> @@ -621,6 +621,26 @@ static void _update_pll_cpcon(struct tegra_clk_pll *pll,
> pll_writel_misc(val, pll);
> }
>
> +static void pll_clk_start_ss(struct tegra_clk_pll *pll)
> +{
> + if (pll->params->defaults_set && pll->params->ssc_ctrl_en_mask) {

defaults_set looks like it's introduced later (patch 16/20). Can you
remove references to that, or reorder the patches if that makes more
sense?

> + u32 val = pll_readl(pll->params->ssc_ctrl_reg, pll);
> +
> + val |= pll->params->ssc_ctrl_en_mask;
> + pll_writel(val, pll->params->ssc_ctrl_reg, pll);
> + }
> +}
> +
> +static void pll_clk_stop_ss(struct tegra_clk_pll *pll)
> +{
> + if (pll->params->defaults_set && pll->params->ssc_ctrl_en_mask) {

Ditto here for defaults_set.

> diff --git a/drivers/clk/tegra/clk.h b/drivers/clk/tegra/clk.h
> index eb8103ec335e..3f92f1ad3961 100644
> --- a/drivers/clk/tegra/clk.h
> +++ b/drivers/clk/tegra/clk.h
> @@ -219,6 +219,8 @@ struct tegra_clk_pll_params {
> u32 sdm_din_mask;
> u32 sdm_ctrl_reg;
> u32 sdm_ctrl_en_mask;
> + u32 ssc_ctrl_reg;
> + u32 ssc_ctrl_en_mask;

Please add kerneldoc for these.





--
Benson Leung
Software Engineer, Chrom* OS
bleung@xxxxxxxxxxxx
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