Re: [PATCH v2 3/6] clk: ingenic: Read bypass register only when there is one

[Zhou Yanjie <zhouyanjie@xxxxxxxxxxxxxx>]

On 2021/5/31 上午12:49, Paul Cercueil wrote:
> Rework the clock code so that the bypass register is only read when
> there is actually a bypass functionality.
>
> Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx>
> ---
>   drivers/clk/ingenic/cgu.c | 19 +++++++++++--------
>   1 file changed, 11 insertions(+), 8 deletions(-)


Tested-by: 周琰杰 (Zhou Yanjie)<zhouyanjie@xxxxxxxxxxxxxx>    # on CU1830-neo/X1830


> diff --git a/drivers/clk/ingenic/cgu.c b/drivers/clk/ingenic/cgu.c
> index 0619d45a950c..7686072aff8f 100644
> --- a/drivers/clk/ingenic/cgu.c
> +++ b/drivers/clk/ingenic/cgu.c
> @@ -99,13 +99,14 @@ ingenic_pll_recalc_rate(struct clk_hw *hw, unsigned long parent_rate)
>   	od_enc = ctl >> pll_info->od_shift;
>   	od_enc &= GENMASK(pll_info->od_bits - 1, 0);
>   
> -	ctl = readl(cgu->base + pll_info->bypass_reg);
> +	if (!pll_info->no_bypass_bit) {
> +		ctl = readl(cgu->base + pll_info->bypass_reg);
>   
> -	bypass = !pll_info->no_bypass_bit &&
> -		 !!(ctl & BIT(pll_info->bypass_bit));
> +		bypass = !!(ctl & BIT(pll_info->bypass_bit));
>   
> -	if (bypass)
> -		return parent_rate;
> +		if (bypass)
> +			return parent_rate;
> +	}
>   
>   	for (od = 0; od < pll_info->od_max; od++) {
>   		if (pll_info->od_encoding[od] == od_enc)
> @@ -225,11 +226,13 @@ static int ingenic_pll_enable(struct clk_hw *hw)
>   	u32 ctl;
>   
>   	spin_lock_irqsave(&cgu->lock, flags);
> -	ctl = readl(cgu->base + pll_info->bypass_reg);
> +	if (!pll_info->no_bypass_bit) {
> +		ctl = readl(cgu->base + pll_info->bypass_reg);
>   
> -	ctl &= ~BIT(pll_info->bypass_bit);
> +		ctl &= ~BIT(pll_info->bypass_bit);
>   
> -	writel(ctl, cgu->base + pll_info->bypass_reg);
> +		writel(ctl, cgu->base + pll_info->bypass_reg);
> +	}
>   
>   	ctl = readl(cgu->base + pll_info->reg);
>