Hi, Le vendredi 25 mars 2016 à 09:14 +0100, 'Enrique' via linux-sunxi a écrit : > Do you have any free 100% guaranteed ARM board with all available board > with all published source code for TZ, ROM or memory handler?
The bootrom code, that is first executed by the processor when it boots up, is proprietary. Since it is stored in read-only memory (as part of the SoC's silicon), it couldn't be free software as the hardware description of the rest of the SoC is not free. With that configuration, the bootrom could only be free given the ability to recreate an entire chip with the modifications. Note that even if the full hardware description of the SoC was released under a free license, including the code for the bootrom, people couldn't afford to produce modified versions, given the costs of producing silicon chips. Overall, freedom on the bootrom is at the same state as hardware freedom: it's out of reach for now. Still, free source code and hardware description would be quite meaningful, for instance to understand how it works. Note that the massive use of third party blocks (called IP blocks) to create the SoC by Allwinner doesn't put them in a position to liberate their SoC hardware designs. Note that the bootrom code was investigated by the community: http://linux-sunxi .org/BROM Regarding replaceable software, Allwinner chips (A10-A33) generally work well with free software, with the exception of the GPU. Unlike many other SoCs, it does not enforce signature checks on the first bootloader to allow running it, which makes it possible to have free bootloaders. Some boards might however require proprietary firmwares (either loaded or preinstalled in chips). You can refer to http://www.fsf.org/resources/hw/single-board-computers for more information (not covering preinstalled non-free firmwares, assimilated to hardware by the FSF). Note that boards don't perform equally regarding hardware freedom: some have free PCB hardware designs, some have documented hardware and some others don't. Keep in mind that all the chips on those boards are proprietary hardware. Newer Allwinner SoCs might require more proprietary bits, such as CPU microcode updates for armv8. In addition, a power-management coprocessor was recently introduced in newer chips (e.g. in H3 if I recall correctly) and might be running a proprietary firmware. This is yet to be investigated and confirmed. Regarding TrustZone, I am not aware of it being used on Allwinner. Cheers > On 2016-03-25 06:30, Support - OLIMEX Ltd wrote: > > > > Hi > > I'm not Linux expert, to the best of my knowledge A20 has everything > > open, but you have to ask on Linux-Sunxi mailing list as they know > > better > > Best regards > > Tsvetan > > > > On 03/24/2016 10:41 PM, Enrique wrote: > > > > > > Hi > > > > > > Do you have any free 100% guaranteed ARM board with all available > > > board > > > with all published source code > > > for TZ, ROM or memory handler? > > > > > > Thanks > > > Regards > > > Enrique > > > -- Paul Kocialkowski, low-level free software developer on embedded devices Website: https://www.paulk.fr/ Coding blog: https://code.paulk.fr/ Git repositories: https://git.paulk.fr/ https://git.code.paulk.fr/ -- 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.
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