On Thu, 21 Apr 2016 16:14:13 -0400 "[email protected]" <[email protected]> wrote:
> On Thu, Apr 21, 2016 at 4:09 PM, Siarhei Siamashka > <[email protected]> wrote: > > On Thu, 21 Apr 2016 13:38:19 -0400 > > "[email protected]" <[email protected]> wrote: > > > >> On Thu, Apr 21, 2016 at 1:17 PM, Siarhei Siamashka > >> <[email protected]> wrote: > >> > Hello, > >> > > >> > On Thu, 21 Apr 2016 11:24:56 -0400 > >> > "[email protected]" <[email protected]> wrote: > >> > > >> >> The manual is very sparse on this subject. Does anyone know what order > >> >> it looks at the MMC options? > >> >> > >> >> For example - MMC flash and an SD Card socket. For brick recovery it > >> >> should be possible to put in an SD Card with a proper boot sector > >> >> (right signature) and then boot from the SD Card overriding the MMC > >> >> flash. > >> > >> Thanks for info. > >> > >> > > >> > We don't have full details yet, but it looks like the boot order > >> > on Allwinner A64 is somewhat similar to > >> > https://linux-sunxi.org/Boot#A31 > >> > > >> > For example, the Jide Remix Mini device boots from the internal > >> > eMMC by default, but the user can override the boot order by > >> > pressing the FEL button: > >> > https://linux-sunxi.org/Jide_Remix_Mini#FEL_mode > >> > > >> > And if I understand it correctly, most of the Allwinner based devices > >> > (at least the ones which do not deviate from the reference schematics) > >> > are perfectly unbrickable: > >> > > >> > http://lists.infradead.org/pipermail/linux-arm-kernel/2015-October/380686.html > >> > > >> > When somebody gets an A64 tablet, I strongly suspect that one of the > >> > volume control buttons is going to be connected to the FEL pin too. > >> > But we can't be 100% sure until somebody confirms this. > >> > > >> > Why are you asking this question? > >> > >> We are designing A64 board for an embedded system. > >> > >> I don't see any boot A64 jumpers for picking one of the four modes -- > >> sel[0:1] > > > > You are right. There are no UBOOT_SEL pins in the A64 datasheet. This > > probably means that there is some hardcoded boot order in the case if > > the FEL button is not pressed. But we haven't seen anything other than > > the SD card and the eMMC as a bootable media yet > > > > BTW, did you reply off-list on purpose? > > no, i just must have touched wrong reply key OK, adding the linux-sunxi mailing list back to CC :-) I have also tried to experiment a bit and added the actual A64 boot sequence information to the wiki: https://linux-sunxi.org/BROM#A64 As for designing an A64 board, unless you really want a 64-bit processor, something like Allwinner H3 might be a better choice right now. At least it is currently better supported in software and has more USB ports. ARM Cortex-A53 is faster than ARM Cortex-A7 per MHz, but it is also more power hungry. Do you have any contacts at Allwinner? Probably not, because otherwise you would not be asking the A64 boot sequence questions here. -- Best regards, Siarhei Siamashka -- You received this message because you are subscribed to the Google Groups "linux-sunxi" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
