[U-Boot] SAMA5D2 xplained SD/eMMC boot

[Yang, Wenyou]

Hi,

> -----Original Message-----
> From: Marek Vasut [mailto:marex at denx.de]
> Sent: 2016年4月21日 10:41
> To: Yang, Wenyou <Wenyou.Yang at atmel.com>
> Cc: u-boot at lists.denx.de
> Subject: Re: SAMA5D2 xplained SD/eMMC boot
> 
> On 04/21/2016 04:30 AM, Yang, Wenyou wrote:
> > Hi Marek,
> 
> Hi!
> 
> >> -----Original Message-----
> >> From: Marek Vasut [mailto:marex at denx.de]
> >> Sent: 2016年4月20日 17:37
> >> To: Yang, Wenyou <Wenyou.Yang at atmel.com>
> >> Cc: u-boot at lists.denx.de
> >> Subject: Re: SAMA5D2 xplained SD/eMMC boot
> 
> Can you fix your mailer so it doesn't insert this crap into each and every message ?
> Pretty please ?
> 
> >> On 04/20/2016 03:17 AM, Yang, Wenyou wrote:
> >>> Hi Marek,
> >>>
> >>>> -----Original Message-----
> >>>> From: Marek Vasut [mailto:marex at denx.de]
> >>>> Sent: 2016年4月20日 0:34
> >>>> To: Yang, Wenyou <Wenyou.Yang at atmel.com>
> >>>> Cc: u-boot at lists.denx.de
> >>>> Subject: Re: SAMA5D2 xplained SD/eMMC boot
> >>>>
> >>>> On 04/19/2016 05:22 AM, Yang, Wenyou wrote:
> >>>>> Hi Marek,
> >>>>>
> >>>>>> -----Original Message-----
> >>>>>> From: Marek Vasut [mailto:marek.vasut at gmail.com]
> >>>>>> Sent: 2016年4月18日 23:30
> >>>>>> To: Yang, Wenyou <Wenyou.Yang at atmel.com>
> >>>>>> Cc: u-boot at lists.denx.de
> >>>>>> Subject: SAMA5D2 xplained SD/eMMC boot
> >>>>>>
> >>>>>> Hi!
> >>>>>>
> >>>>>> I've been playing around with latest mainline u-boot on sama5d2
> >>>>>> xplained ultra. I noticed that if I want to boot the board from
> >>>>>> SD card (SDHCI1), the board will indeed load the SPL from it, but
> >>>>>> SPL will try to load u-boot.img from eMMC
> >>>>>> (SDHCI0) and fail, as my eMMC is blank.
> >>>>>
> >>>>> Yes, there is some issue to load u-boot.img. I found there is
> >>>>> something to do on
> >>>> sdhci.c.
> >>>>>
> >>>>> You can try this branch, it should works.
> >>>>>
> >>>>> https://github.com/linux4sam/u-boot-at91/commits/u-boot-2016.03-at
> >>>>> 91
> >>>>
> >>>> I am not interested in using non-mainline stuff. Do you have any
> >>>> particular patch/commit which I can refer to ? I do not think this
> >>>> has anything to do with sdhci.c driver at all, it has to do with
> >>>> detecting the boot device from which SPL was started and loading
> >>>> u-boot.img from the same boot device instead of always using SDHCI0.
> >>>
> >>> I will test the mainline code. I will let you know when I get something.
> >>
> >> OK.
> >>
> >> Does the SoC have any sort of register which lists the current boot device ?
> >
> > In this SoC, there is not register to list the current boot device.
> 
> And thus, it is not possible to detect at runtime from which device the SoC booted
> and thus load u-boot.img from the same device. Correct ?

Yes, 

> 
> You should add such register, it's a few lines of HDL ...

Good suggestion.

Recorded.

Thank you.

> 
> [...]
> Best regards,
> Marek Vasut


Best Regards
Wenyou Yang