Re: [PATCH v5 3/5] mmc: mediatek: refine msdc timeout api

["yong.mao-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org" <yong.mao-NuS5LvNUpcJWk0Htik3J/w@public.gmane.org>]

On Tue, 2020-04-28 at 07:56 +0800, Chun-Hung Wu wrote:
> Extract msdc timeout api common part to have
> better code architecture and avoid redundent
please correct the word "redundant" in next version
> code.
> 
> Signed-off-by: Chun-Hung Wu <chun-hung.wu@mediatek.com>
Acked-by: Yong Mao <yong.mao@mediatek.com>
> ---
>  drivers/mmc/host/mtk-sd.c | 32 ++++++++++++++++++++++----------
>  1 file changed, 22 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/mmc/host/mtk-sd.c b/drivers/mmc/host/mtk-sd.c
> index 7726dcf..a2328fb 100644
> --- a/drivers/mmc/host/mtk-sd.c
> +++ b/drivers/mmc/host/mtk-sd.c
> @@ -699,21 +699,21 @@ static void msdc_unprepare_data(struct msdc_host *host, struct mmc_request *mrq)
>  	}
>  }
>  
> -/* clock control primitives */
> -static void msdc_set_timeout(struct msdc_host *host, u32 ns, u32 clks)
> +static u64 msdc_timeout_cal(struct msdc_host *host, u64 ns, u64 clks)
>  {
> -	u32 timeout, clk_ns;
> +	u64 timeout, clk_ns;
>  	u32 mode = 0;
>  
> -	host->timeout_ns = ns;
> -	host->timeout_clks = clks;
>  	if (host->mmc->actual_clock == 0) {
>  		timeout = 0;
>  	} else {
> -		clk_ns  = 1000000000UL / host->mmc->actual_clock;
> -		timeout = (ns + clk_ns - 1) / clk_ns + clks;
> +		clk_ns  = 1000000000ULL;
> +		do_div(clk_ns, host->mmc->actual_clock);
> +		timeout = ns + clk_ns - 1;
> +		do_div(timeout, clk_ns);
> +		timeout += clks;
>  		/* in 1048576 sclk cycle unit */
> -		timeout = (timeout + (0x1 << 20) - 1) >> 20;
> +		timeout = DIV_ROUND_UP(timeout, (0x1 << 20));
>  		if (host->dev_comp->clk_div_bits == 8)
>  			sdr_get_field(host->base + MSDC_CFG,
>  				      MSDC_CFG_CKMOD, &mode);
> @@ -723,9 +723,21 @@ static void msdc_set_timeout(struct msdc_host *host, u32 ns, u32 clks)
>  		/*DDR mode will double the clk cycles for data timeout */
>  		timeout = mode >= 2 ? timeout * 2 : timeout;
>  		timeout = timeout > 1 ? timeout - 1 : 0;
> -		timeout = timeout > 255 ? 255 : timeout;
>  	}
> -	sdr_set_field(host->base + SDC_CFG, SDC_CFG_DTOC, timeout);
> +	return timeout;
> +}
> +
> +/* clock control primitives */
> +static void msdc_set_timeout(struct msdc_host *host, u64 ns, u64 clks)
> +{
> +	u64 timeout;
> +
> +	host->timeout_ns = ns;
> +	host->timeout_clks = clks;
> +
> +	timeout = msdc_timeout_cal(host, ns, clks);
> +	sdr_set_field(host->base + SDC_CFG, SDC_CFG_DTOC,
> +		      (u32)(timeout > 255 ? 255 : timeout));
>  }
>  
>  static void msdc_gate_clock(struct msdc_host *host)