[U-Boot] [PATCH 1/3] mmc: fsl_esdhc: enable dat[4:7] for eMMC4.5

York Sun yorksun at freescale.com
Tue Sep 15 04:29:52 CEST 2015



On 09/14/2015 07:22 PM, Lu Yangbo-B47093 wrote:
> Hi York,
> 
> Please see my comments below.
> 
>> -----Original Message-----
>> From: Sun York-R58495
>> Sent: Monday, September 14, 2015 11:57 PM
>> To: Lu Yangbo-B47093; u-boot at lists.denx.de
>> Subject: Re: [PATCH 1/3] mmc: fsl_esdhc: enable dat[4:7] for eMMC4.5
>>
>> Yangbo,
>>
>> On 09/13/2015 08:04 PM, Yangbo Lu wrote:
>>> If adapter card type identification is supported for platform, we
>>> would enable dat[4:7] for eMMC4.5 card.
>>>
>>> Signed-off-by: Yangbo Lu <yangbo.lu at freescale.com>
>>> Cc: York Sun <yorksun at freescale.com>
>>> ---
>>>  board/freescale/common/qixis.h | 2 ++
>>>  drivers/mmc/fsl_esdhc.c        | 3 +++
>>>  2 files changed, 5 insertions(+)
>>>
>>> diff --git a/board/freescale/common/qixis.h
>>> b/board/freescale/common/qixis.h index 51ce9c3..450cd0d 100644
>>> --- a/board/freescale/common/qixis.h
>>> +++ b/board/freescale/common/qixis.h
>>> @@ -127,6 +127,8 @@ void qixis_write_i2c(unsigned int reg, u8 value);
>>>  #define QIXIS_ESDHC_NO_ADAPTER                  0x7	/* No Card is
>> Present*/
>>>  #define QIXIS_SDCLKIN		0x08
>>>  #define QIXIS_SDCLKOUT		0x02
>>> +#define QIXIS_DAT5_6_7		0X02
>>> +#define QIXIS_DAT4		0X01
>>>  #endif
>>>
>>>  #endif
>>> diff --git a/drivers/mmc/fsl_esdhc.c b/drivers/mmc/fsl_esdhc.c index
>>> 0b37002..639ec02 100644
>>> --- a/drivers/mmc/fsl_esdhc.c
>>> +++ b/drivers/mmc/fsl_esdhc.c
>>> @@ -747,6 +747,9 @@ void mmc_adapter_card_type_ident(void)
>>>
>>>  	switch (card_id) {
>>>  	case QIXIS_ESDHC_ADAPTER_TYPE_EMMC45:
>>> +		value = QIXIS_READ(brdcfg[5]);
>>> +		value |= (QIXIS_DAT4 | QIXIS_DAT5_6_7);
>>> +		QIXIS_WRITE(brdcfg[5], value);
>>>  		break;
>>>  	case QIXIS_ESDHC_ADAPTER_TYPE_SDMMC_LEGACY:
>>>  		break;
>>>
>>
>> Does any other board have this identification feature? I see the code
>> only use qixis. How are RDB and customer boards handled?
>>
>> York
> [Lu Yangbo-B47093] This feature is used for QDS boards that use SDHC Adapter card. Now only T1040QDS and T2080QDS are enabled, because we want to support SD/MMC UHS-I speed mode on these two boards in kernel and these QIXIS configuration are needed for *the Adapter*. For RDB and customer boards, they don't use Adapter card and the default configuration is ok for SD/MMC Default speed mode and High speed mode.
> 

I am actually more concerned how a customer board can take advantage of this.

York


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