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

[Lu Y.B.]

> 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
[Lu Yangbo-B47093] This feature is used to resolve pin multiplexing and Adapter card configuration on QDS board.
RDB and custom boards don't support Adapter card, and the FPGA/CPLD is easier(don't have these register and settings), having no need to change.
So they couldn't take advantage of this... 

Thanks.

-Yangbo Lu