[U-Boot] [PATCH] mmc: sdhci: Fix maximum clock for programmable clock mode

[Jaehoon Chung]

Hi Wenyou,

On 04/26/2017 10:32 AM, Wenyou Yang wrote:
> In the programmable clock mode, the SDCLK frequency is incorrectly
> assigned when the maximum clock has been assigned during probe,
> this causes the SDHCI not work well.
> 
> In the programmable clock mode, when calculating the SDCLK Frequency
> Select, when the maximum clock has been assigned, it is the actual
> value, should not be multiplied by host->clk_mul. Otherwise, the
> maximum clock is multiplied host->clk_mul by the base clock achieved
> from the BASECLKF field of the Capabilities 0 Register.
> 
> Signed-off-by: Wenyou Yang <wenyou.yang at atmel.com>

Applied to u-boot-mmc. Thanks.

Best Regards,
Jaehoon Chung

> ---
> 
>  drivers/mmc/sdhci.c | 18 +++++++++++-------
>  1 file changed, 11 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c
> index b745977b3f..161a6b1399 100644
> --- a/drivers/mmc/sdhci.c
> +++ b/drivers/mmc/sdhci.c
> @@ -332,8 +332,7 @@ static int sdhci_set_clock(struct mmc *mmc, unsigned int clock)
>  		 */
>  		if (host->clk_mul) {
>  			for (div = 1; div <= 1024; div++) {
> -				if ((host->max_clk * host->clk_mul / div)
> -					<= clock)
> +				if ((host->max_clk / div) <= clock)
>  					break;
>  			}
>  
> @@ -547,6 +546,14 @@ int sdhci_setup_cfg(struct mmc_config *cfg, struct sdhci_host *host,
>  #ifndef CONFIG_DM_MMC_OPS
>  	cfg->ops = &sdhci_ops;
>  #endif
> +
> +	/* Check whether the clock multiplier is supported or not */
> +	if (SDHCI_GET_VERSION(host) >= SDHCI_SPEC_300) {
> +		caps_1 = sdhci_readl(host, SDHCI_CAPABILITIES_1);
> +		host->clk_mul = (caps_1 & SDHCI_CLOCK_MUL_MASK) >>
> +				SDHCI_CLOCK_MUL_SHIFT;
> +	}
> +
>  	if (host->max_clk == 0) {
>  		if (SDHCI_GET_VERSION(host) >= SDHCI_SPEC_300)
>  			host->max_clk = (caps & SDHCI_CLOCK_V3_BASE_MASK) >>
> @@ -555,6 +562,8 @@ int sdhci_setup_cfg(struct mmc_config *cfg, struct sdhci_host *host,
>  			host->max_clk = (caps & SDHCI_CLOCK_BASE_MASK) >>
>  				SDHCI_CLOCK_BASE_SHIFT;
>  		host->max_clk *= 1000000;
> +		if (host->clk_mul)
> +			host->max_clk *= host->clk_mul;
>  	}
>  	if (host->max_clk == 0) {
>  		printf("%s: Hardware doesn't specify base clock frequency\n",
> @@ -590,11 +599,6 @@ int sdhci_setup_cfg(struct mmc_config *cfg, struct sdhci_host *host,
>  	if (SDHCI_GET_VERSION(host) >= SDHCI_SPEC_300) {
>  		if (!(caps & SDHCI_CAN_DO_8BIT))
>  			cfg->host_caps &= ~MMC_MODE_8BIT;
> -
> -		/* Find out whether clock multiplier is supported */
> -		caps_1 = sdhci_readl(host, SDHCI_CAPABILITIES_1);
> -		host->clk_mul = (caps_1 & SDHCI_CLOCK_MUL_MASK) >>
> -				SDHCI_CLOCK_MUL_SHIFT;
>  	}
>  
>  	if (host->host_caps)
>