[U-Boot] [PATCH 2/2 v3] FSL/eSDHC: enable the clock to detect the SD card

[Huang Changming-R66093]

VVN2.2/VVN2.3 is the vendor version number, that is the FSL SDHC IP verion.

Best Regards
Jerry Huang


> -----Original Message-----
> From: Marek Vasut [mailto:marex at denx.de]
> Sent: Saturday, May 19, 2012 12:03 AM
> To: Huang Changming-R66093
> Cc: u-boot at lists.denx.de; Andy Fleming
> Subject: Re: [PATCH 2/2 v3] FSL/eSDHC: enable the clock to detect the SD
> card
> 
> Dear Chang-Ming.Huang at freescale.com,
> 
> > From: Jerry Huang <Chang-Ming.Huang at freescale.com>
> >
> > For FSL low-end processors (VVN2.2)
> 
> What's VVN2.2 ?
> 
> > , in order to detect the SD card,
> > we should enable PEREN, HCKEN and IPGEN to enable the clock.
> > Otherwise, after booting the u-boot, and then inserting the SD card,
> > the SD card can't be detected.
> > For SDHC VVN2.3 IP
> 
> VVN2.3 ?
> 
> > , these bits are reserved, and SDCLKEN is used.
> > And when accessing to these reserved bit, no any impact happened.
> >
> > Signed-off-by: Jerry Huang <Chang-Ming.Huang at freescale.com>
> > CC: Andy Fleming <afleming at gmail.com>
> > CC: Marek Vasut <marex at denx.de>
> > ---
> > changes for v2:
> > 	- correct the typo
> > changes for v3:
> > 	- enable all clock bits for VVN2.3 and VVN2.2
> > 	- use funciton esdhc_setbits32
> > 	- tested on p1022ds, p1025rdb, p1020mbg-pc, mpc8536ds, p3041ds
> >
> >  drivers/mmc/fsl_esdhc.c |    3 +++
> >  1 files changed, 3 insertions(+), 0 deletions(-)
> >
> > diff --git a/drivers/mmc/fsl_esdhc.c b/drivers/mmc/fsl_esdhc.c index
> > a2f35e3..930a5c5 100644
> > --- a/drivers/mmc/fsl_esdhc.c
> > +++ b/drivers/mmc/fsl_esdhc.c
> > @@ -491,6 +491,9 @@ int fsl_esdhc_initialize(bd_t *bis, struct
> > fsl_esdhc_cfg *cfg) /* First reset the eSDHC controller */
> >  	esdhc_reset(regs);
> >
> > +	esdhc_setbits32(&regs->sysctl, SYSCTL_PEREN | SYSCTL_HCKEN
> > +				| SYSCTL_IPGEN | SYSCTL_CKEN);
> > +
> >  	mmc->priv = cfg;
> >  	mmc->send_cmd = esdhc_send_cmd;
> >  	mmc->set_ios = esdhc_set_ios;
> 
> Best regards,
> Marek Vasut