From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marek Vasut Date: Tue, 26 Apr 2016 14:42:40 +0200 Subject: [U-Boot] SAMA5D2 xplained SD/eMMC boot In-Reply-To: References: <5714FD86.4040309@gmail.com> <57165DFD.5040603@denx.de> <57174DA0.3040401@denx.de> <57183DD8.2030302@denx.de> <571841E5.8010602@denx.de> <571A1670.7020102@denx.de> <571DF1B4.2070208@denx.de> Message-ID: <571F6240.7060003@denx.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On 04/26/2016 03:47 AM, Yang, Wenyou wrote: > > >> -----Original Message----- >> From: Marek Vasut [mailto:marex at denx.de] >> Sent: 2016?4?25? 18:30 >> To: Yang, Wenyou >> Cc: u-boot at lists.denx.de >> Subject: Re: SAMA5D2 xplained SD/eMMC boot >> >> On 04/25/2016 02:55 AM, Yang, Wenyou wrote: >>> Hi Marek, >>> >>>> -----Original Message----- >>>> From: Marek Vasut [mailto:marex at denx.de] >>>> Sent: 2016?4?22? 20:18 >>>> To: Yang, Wenyou >>>> Cc: u-boot at lists.denx.de >>>> Subject: Re: SAMA5D2 xplained SD/eMMC boot >>>> >>>> On 04/22/2016 02:54 AM, Yang, Wenyou wrote: >>>>> Hi Marek, >>>> >>>> Hi! >>>> >>>>>> -----Original Message----- >>>>>> From: Marek Vasut [mailto:marex at denx.de] >>>>>> Sent: 2016?4?21? 10:59 >>>>>> To: Yang, Wenyou >>>>>> Cc: u-boot at lists.denx.de >>>>>> Subject: Re: SAMA5D2 xplained SD/eMMC boot >>>>>> >>>>>> On 04/21/2016 04:46 AM, Yang, Wenyou wrote: >>>>>>> Hi, >>>>>> >>>>>> Hi! >>>>>> >>>>>> [...] >>>>>> pile of unnecessary email headers redacted. >>>>>> [...] >>>>>> >>>>>>>>>>>>>> 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 >>>>>>>>>>>>> .0 >>>>>>>>>>>>> 3- >>>>>>>>>>>>> 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, >>>>>> >>>>>> Ha, thanks for confirming. >>>>> >>>>> Sorry, can I correct what I said yesterday? >>>> >>>> What if I said "no" ? :-) >>>> >>>>> There is a register to list the boot information exported by ROMCode. >>>>> >>>>> The boot information is stored in R4 register when the ROMCode jumps >>>>> to the >>>> bootstrap. >>>> >>>> Ha, so the U-Boot SPL can save the r4 register early in the boot and >>>> extract the boot device from it. That's neat. Thanks! >>>> >>>>> Here is the contents definitions R4 on the SAMA5D2 (improved >>>>> compared to old >>>> MPUs to take care of IOSet features). >>>> >>>> Is this stuff somewhere in the SAMA5Dx datasheet ? It'd be nice to >>>> know/have this information for other SAMA5Dx too (d3 and d4). >>> >>> It seems it is not included in the in the SAMA5Dx datasheet. >> >> So where did you get these numbers from ? > > Yes, it is not included in the datasheet now. We are not recommend to use them. > > If it is helpful for you, please reference the previous mail. It is helpful, I sent a patch for SAMA5D2 which makes it behave sane. I will have to battle SAMA5D4 board soon, so I will most likely extend that patch for SAMA5D4. >> >>> This feature is available since AT91SAM9G45, inclusive d3 and d4. >> >> Oh cool, so the numbers are the same for all these chips ? > > Yes, basically same, only d2 includes additional ioset information. OK, the IOSET is not interesting for now. It'd be cool to have this documented somewhere :) Best regards, Marek Vasut