On Thu, 7 Apr 2022 13:53:23 +0200 Pali Rohár <p...@kernel.org> wrote:
> On Wednesday 06 April 2022 21:21:59 Marek Behún wrote: > > On Wed, 6 Apr 2022 14:18:18 +0200 > > Pali Rohár <p...@kernel.org> wrote: > > > > > Armada 385 contains 64 lines of HD eFuse and 2 lines of LD eFuse. HD eFuse > > > is used for secure boot and each line is 64 bits long + 1 lock bit. LD > > > eFuse lines are 256 bits long + 1 lock bit. LD 0 line is reserved for > > > Marvell Internal Use and LD 1 line is for General Purpose Data. U-Boot > > > already contains HD eFuse reading and programming support. > > > > > > This patch implements LD eFuse reading support. LD 0 line is mapped to > > > U-Boot fuse bank 64 and LD 1 line to fuse bank 65. > > > > > > LD 0 Marvell Internal Use line seems that was burned in factory with some > > > data and can be read by U-Boot fuse command: > > > > > > => fuse read 64 0 9 > > > > > > LD 1 General Purpose Data line is by default empty and can be read by > > > U-Boot fuse command: > > > > > > => fuse read 65 0 9 > > > > > > Signed-off-by: Pali Rohár <p...@kernel.org> > > > > I am not sure whether this can be used safely on Turris Omnia - there > > was some issue with voltage or something, I know for sure that burning > > does not work on Omnia, but I am not sure if the issue also prevents > > stable reading. > > On A385 there is errata only for programming OTP bits. > > > Are the values you read always the same? Even across power cycles? > > > > Marek > > Reading is working fine and is stable also after power cycles. Marvell > Internal Use contains data which are same after more reads. In that case Reviewed-by: Marek Behún <marek.be...@nic.cz>