[U-Boot] [PATCH] spl_mmc: always use find_mmc_device() to get mmc handler

[Peng Fan]

> Subject: Re: [U-Boot] [PATCH] spl_mmc: always use find_mmc_device() to get
> mmc handler
> 
> +Peng
> 
> Hi Kever,
> 
> On 25/07/19 3:10 PM, Kever Yang wrote:
> > Like cmd/mmc.c, the spl_mmc.c are using block driver interface like
> > blk_dread() to access mmc devices, we need to get the mmc device
> > handler by block driver interface so that we can always get correct
> > device number, eg. the alias may change the device number which make
> > the device number different in UCLASS_MMC list and UCLASS_BLK list.

It is unclear to me.
spl_mmc_get_device_index will get the mmc_dev number,
Then uclass_get_device will use it to get the mmc device.

You mean this not work on your platform?

And mmc device and blk device are connected with the uclass_platdata of
the mmc device, so from mmc, you could always get the correct blk device.

Please share more info about your issue/fix.

Regards,
Peng.


> >
> > Signed-off-by: Kever Yang <kever.yang at rock-chips.com>
> > ---
> >
> >  common/spl/spl_mmc.c | 9 ---------
> >  1 file changed, 9 deletions(-)
> >
> > diff --git a/common/spl/spl_mmc.c b/common/spl/spl_mmc.c index
> > b3619889f7..3a93e20f04 100644
> > --- a/common/spl/spl_mmc.c
> > +++ b/common/spl/spl_mmc.c
> > @@ -113,9 +113,6 @@ static int spl_mmc_get_device_index(u32
> > boot_device)
> >
> >  static int spl_mmc_find_device(struct mmc **mmcp, u32 boot_device)  {
> > -#if CONFIG_IS_ENABLED(DM_MMC)
> > -	struct udevice *dev;
> > -#endif
> >  	int err, mmc_dev;
> >
> >  	mmc_dev = spl_mmc_get_device_index(boot_device);
> > @@ -130,14 +127,8 @@ static int spl_mmc_find_device(struct mmc
> **mmcp, u32 boot_device)
> >  		return err;
> >  	}
> >
> > -#if CONFIG_IS_ENABLED(DM_MMC)
> > -	err = uclass_get_device(UCLASS_MMC, mmc_dev, &dev);
> > -	if (!err)
> > -		*mmcp = mmc_get_mmc_dev(dev);
> > -#else
> >  	*mmcp = find_mmc_device(mmc_dev);
> >  	err = *mmcp ? 0 : -ENODEV;
> > -#endif
> 
> I am not against the change but trying to understand what is the problem you
> faced. mmc_initialize() would have initialized the devices based on the seq
> number that is provided in DT. So in your case shouldn't uclass_get_device
> give the right device or something else triggered this patch?
> 
> Also we are facing a different problem with mmc_initialize(). Very early in
> boot there is no access to any peripheral other than boot peripheral(Need
> system co processor to enable peripherals). There are 2 MMC controllers in
> our devices.
> So, SD boot is failing while loading system firmware as mmc_initialize is trying
> to probe both the controllers. In SPL, shouldn't we just probe the needed
> controller instead of calling mmc_initialize?
> 
> Thanks and regards,
> Lokesh