[U-Boot] [PATCH v1 2/3] Add support for save environment variable to MMC/SD card

[Hu Mingkai-B21284]

> -----Original Message-----
> From: Wolfgang Denk [mailto:wd at denx.de] 
> Sent: Wednesday, September 23, 2009 2:54 AM
> To: Hu Mingkai-B21284
> Cc: u-boot at lists.denx.de; Wood Scott-B07421; Gala Kumar-B11780
> Subject: Re: [U-Boot] [PATCH v1 2/3] Add support for save 
> environment variable to MMC/SD card
> 
> Dear Mingkai Hu,
> 
> In message 
> <1252640445-7890-3-git-send-email-Mingkai.hu at freescale.com> you wrote:
> > Whether booting from MMC/SD card or not, the environment 
> variables can 
> > be saved on it, this patch add the operation support.
> > 
> > Signed-off-by: Mingkai Hu <Mingkai.hu at freescale.com>
> ...
> > --- a/common/Makefile
> > +++ b/common/Makefile
> > @@ -61,6 +61,7 @@ COBJS-$(CONFIG_ENV_IS_IN_NAND) += env_nand.o
> >  COBJS-$(CONFIG_ENV_IS_IN_NVRAM) += env_nvram.o
> >  COBJS-$(CONFIG_ENV_IS_IN_ONENAND) += env_onenand.o
> >  COBJS-$(CONFIG_ENV_IS_IN_SPI_FLASH) += env_sf.o
> > +COBJS-$(CONFIG_ENV_IS_IN_SDCARD) += env_sdcard.o
> >  COBJS-$(CONFIG_ENV_IS_NOWHERE) += env_nowhere.o
> 
> Please keep the list sorted.
> 
OK.

> >  # command
> > diff --git a/common/cmd_nvedit.c b/common/cmd_nvedit.c index 
> > 2186205..83969ef 100644
> > --- a/common/cmd_nvedit.c
> > +++ b/common/cmd_nvedit.c
> > @@ -60,9 +60,10 @@ DECLARE_GLOBAL_DATA_PTR;
> >      !defined(CONFIG_ENV_IS_IN_NVRAM)	&& \
> >      !defined(CONFIG_ENV_IS_IN_ONENAND)	&& \
> >      !defined(CONFIG_ENV_IS_IN_SPI_FLASH)	&& \
> > +    !defined(CONFIG_ENV_IS_IN_SDCARD)	&& \
> 
> Ditto.
> 
OK.

> >  # error Define one of 
> > CONFIG_ENV_IS_IN_{EEPROM|FLASH|DATAFLASH|ONENAND|\
> > -SPI_FLASH|MG_DISK|NVRAM|NOWHERE}
> > +SPI_FLASH|MG_DISK|NVRAM|SDCARD|NOWHERE}
> 
> Please take the opportunity to sort this list, too. Thanks.
> 
OK.

> ...
> > +int env_init(void)
> > +{
> > +	/* eSDHC isn't usable before relocation */
> > +	gd->env_addr  = (ulong)&default_environment[0];
> > +	gd->env_valid = 1;
> 
> Argh... Does that mean that your environment suddenly changes 
> while running? That you start running from the default 
> environment (which cannot be changed) and then switch to a 
> the real, changable environment?
> 
Yes. I refered to env_sf.c file, maybe it has the same issue.

> This is going to cause a hell of confusion to users who for 
> example want to define a different console baud rate or such...
> 
It's a problem.

Thanks,
Mingkai