[U-Boot] [PATCH] mmc: sdhci: Add the programmable clock mode support

[Jaehoon Chung]

Hi Andreas,

On 08/15/2016 01:17 AM, Andreas Bießmann wrote:
> Dear Pantelis,
> 
> On 20.06.16 03:58, Wenyou Yang wrote:
>> Add the programmable clock mode for the clock generator.
>>
> 
> this one is delegated to me, but I think it is out of my scope. Could
> you please have a look?

I will be delegated to me. I will check this patch.

Thanks.

Best Regards,
Jaehoon Chung

> 
> Andreas
> 
>> Signed-off-by: Wenyou Yang <wenyou.yang at atmel.com>
>> ---
>>
>>  drivers/mmc/sdhci.c | 49 +++++++++++++++++++++++++++++++++++++++----------
>>  include/sdhci.h     | 15 +++++++++++++++
>>  2 files changed, 54 insertions(+), 10 deletions(-)
>>
>> diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c
>> index 5c71ab8..ee6d4a1 100644
>> --- a/drivers/mmc/sdhci.c
>> +++ b/drivers/mmc/sdhci.c
>> @@ -286,7 +286,7 @@ static int sdhci_send_command(struct mmc *mmc, struct mmc_cmd *cmd,
>>  static int sdhci_set_clock(struct mmc *mmc, unsigned int clock)
>>  {
>>  	struct sdhci_host *host = mmc->priv;
>> -	unsigned int div, clk, timeout, reg;
>> +	unsigned int div, clk = 0, timeout, reg;
>>  
>>  	/* Wait max 20 ms */
>>  	timeout = 200;
>> @@ -310,14 +310,35 @@ static int sdhci_set_clock(struct mmc *mmc, unsigned int clock)
>>  		return 0;
>>  
>>  	if (SDHCI_GET_VERSION(host) >= SDHCI_SPEC_300) {
>> -		/* Version 3.00 divisors must be a multiple of 2. */
>> -		if (mmc->cfg->f_max <= clock)
>> -			div = 1;
>> -		else {
>> -			for (div = 2; div < SDHCI_MAX_DIV_SPEC_300; div += 2) {
>> -				if ((mmc->cfg->f_max / div) <= clock)
>> +		/*
>> +		 * Check if the Host Controller supports Programmable Clock
>> +		 * Mode.
>> +		 */
>> +		if (host->clk_mul) {
>> +			for (div = 1; div <= 1024; div++) {
>> +				if ((mmc->cfg->f_max * host->clk_mul / div)
>> +					<= clock)
>>  					break;
>>  			}
>> +
>> +			/*
>> +			 * Set Programmable Clock Mode in the Clock
>> +			 * Control register.
>> +			 */
>> +			clk = SDHCI_PROG_CLOCK_MODE;
>> +			div--;
>> +		} else {
>> +			/* Version 3.00 divisors must be a multiple of 2. */
>> +			if (mmc->cfg->f_max <= clock) {
>> +				div = 1;
>> +			} else {
>> +				for (div = 2;
>> +				     div < SDHCI_MAX_DIV_SPEC_300; div += 2) {
>> +					if ((mmc->cfg->f_max / div) <= clock)
>> +						break;
>> +				}
>> +			}
>> +			div >>= 1;
>>  		}
>>  	} else {
>>  		/* Version 2.00 divisors must be a power of 2. */
>> @@ -325,13 +346,13 @@ static int sdhci_set_clock(struct mmc *mmc, unsigned int clock)
>>  			if ((mmc->cfg->f_max / div) <= clock)
>>  				break;
>>  		}
>> +		div >>= 1;
>>  	}
>> -	div >>= 1;
>>  
>>  	if (host->set_clock)
>>  		host->set_clock(host->index, div);
>>  
>> -	clk = (div & SDHCI_DIV_MASK) << SDHCI_DIVIDER_SHIFT;
>> +	clk |= (div & SDHCI_DIV_MASK) << SDHCI_DIVIDER_SHIFT;
>>  	clk |= ((div & SDHCI_DIV_HI_MASK) >> SDHCI_DIV_MASK_LEN)
>>  		<< SDHCI_DIVIDER_HI_SHIFT;
>>  	clk |= SDHCI_CLOCK_INT_EN;
>> @@ -480,7 +501,7 @@ static const struct mmc_ops sdhci_ops = {
>>  
>>  int add_sdhci(struct sdhci_host *host, u32 max_clk, u32 min_clk)
>>  {
>> -	unsigned int caps;
>> +	unsigned int caps, caps_1;
>>  
>>  	host->cfg.name = host->name;
>>  	host->cfg.ops = &sdhci_ops;
>> @@ -546,6 +567,14 @@ int add_sdhci(struct sdhci_host *host, u32 max_clk, u32 min_clk)
>>  
>>  	host->cfg.b_max = CONFIG_SYS_MMC_MAX_BLK_COUNT;
>>  
>> +	/*
>> +	 * In case of Host Controller v3.00, 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;
>> +
>>  	sdhci_reset(host, SDHCI_RESET_ALL);
>>  
>>  	host->mmc = mmc_create(&host->cfg, host);
>> diff --git a/include/sdhci.h b/include/sdhci.h
>> index e0f6667..5abe0a2 100644
>> --- a/include/sdhci.h
>> +++ b/include/sdhci.h
>> @@ -97,6 +97,7 @@
>>  #define  SDHCI_DIV_MASK	0xFF
>>  #define  SDHCI_DIV_MASK_LEN	8
>>  #define  SDHCI_DIV_HI_MASK	0x300
>> +#define  SDHCI_PROG_CLOCK_MODE  0x0020
>>  #define  SDHCI_CLOCK_CARD_EN	0x0004
>>  #define  SDHCI_CLOCK_INT_STABLE	0x0002
>>  #define  SDHCI_CLOCK_INT_EN	0x0001
>> @@ -166,6 +167,19 @@
>>  #define  SDHCI_CAN_64BIT	0x10000000
>>  
>>  #define SDHCI_CAPABILITIES_1	0x44
>> +#define  SDHCI_SUPPORT_SDR50	0x00000001
>> +#define  SDHCI_SUPPORT_SDR104	0x00000002
>> +#define  SDHCI_SUPPORT_DDR50	0x00000004
>> +#define  SDHCI_DRIVER_TYPE_A	0x00000010
>> +#define  SDHCI_DRIVER_TYPE_C	0x00000020
>> +#define  SDHCI_DRIVER_TYPE_D	0x00000040
>> +#define  SDHCI_RETUNING_TIMER_COUNT_MASK	0x00000F00
>> +#define  SDHCI_RETUNING_TIMER_COUNT_SHIFT	8
>> +#define  SDHCI_USE_SDR50_TUNING			0x00002000
>> +#define  SDHCI_RETUNING_MODE_MASK		0x0000C000
>> +#define  SDHCI_RETUNING_MODE_SHIFT		14
>> +#define  SDHCI_CLOCK_MUL_MASK	0x00FF0000
>> +#define  SDHCI_CLOCK_MUL_SHIFT	16
>>  
>>  #define SDHCI_MAX_CURRENT	0x48
>>  
>> @@ -240,6 +254,7 @@ struct sdhci_host {
>>  	unsigned int quirks;
>>  	unsigned int host_caps;
>>  	unsigned int version;
>> +	unsigned int clk_mul;   /* Clock Muliplier value */
>>  	unsigned int clock;
>>  	struct mmc *mmc;
>>  	const struct sdhci_ops *ops;
>>
> _______________________________________________
> U-Boot mailing list
> U-Boot at lists.denx.de
> http://lists.denx.de/mailman/listinfo/u-boot
> 
> 
>