[PATCH] drm/msm/dsi_pll_7nm: Solve TODO for multiplier frac_bits assignment

abhinavk at codeaurora.org abhinavk at codeaurora.org
Thu Feb 25 07:28:37 UTC 2021


Hi Dmitry

Thanks for the patch.

On 2021-02-24 15:01, Dmitry Baryshkov wrote:
> The number of fractional registers bits is known and already set in
> the frac_bits variable of the dsi_pll_config struct here in 7nm:
> remove the TODO by simply using that variable. This is a copy of
> 196145eb1af1 ("drm/msm/dsi_pll_10nm: Solve TODO for multiplier 
> frac_bits
> assignment").
> 
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov at linaro.org>
Reviewed-by: Abhinav Kumar <abhinavk at codeaurora.org>
> ---
>  drivers/gpu/drm/msm/dsi/pll/dsi_pll_7nm.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/msm/dsi/pll/dsi_pll_7nm.c
> b/drivers/gpu/drm/msm/dsi/pll/dsi_pll_7nm.c
> index c1f6708367ae..0458eda15114 100644
> --- a/drivers/gpu/drm/msm/dsi/pll/dsi_pll_7nm.c
> +++ b/drivers/gpu/drm/msm/dsi/pll/dsi_pll_7nm.c
> @@ -509,6 +509,7 @@ static unsigned long
> dsi_pll_7nm_vco_recalc_rate(struct clk_hw *hw,
>  {
>  	struct msm_dsi_pll *pll = hw_clk_to_pll(hw);
>  	struct dsi_pll_7nm *pll_7nm = to_pll_7nm(pll);
> +	struct dsi_pll_config *config = &pll_7nm->pll_configuration;
>  	void __iomem *base = pll_7nm->mmio;
>  	u64 ref_clk = pll_7nm->vco_ref_clk_rate;
>  	u64 vco_rate = 0x0;
> @@ -529,9 +530,8 @@ static unsigned long
> dsi_pll_7nm_vco_recalc_rate(struct clk_hw *hw,
>  	/*
>  	 * TODO:
>  	 *	1. Assumes prescaler is disabled
> -	 *	2. Multiplier is 2^18. it should be 2^(num_of_frac_bits)
>  	 */
> -	multiplier = 1 << 18;
> +	multiplier = 1 << config->frac_bits;
>  	pll_freq = dec * (ref_clk * 2);
>  	tmp64 = (ref_clk * 2 * frac);
>  	pll_freq += div_u64(tmp64, multiplier);


More information about the dri-devel mailing list