We have a board using Marvell's MV78100 SoC (note despite the name this is quite different to the armada MV782x0/MV784x0 SoCs).
The SoC support isn't upstream but since it's quite similar to the Orion/Kirkwood we've managed to keep reasonably up to date. One difference with our system is that it boots directly from NOR flash (as opposed to many Kirkwood implementations which make use of a pre-bootloader to setup RAM).
Somewhere between v2015.04 and v2015.10 we started seeing a hang at startup. I eventually tracked this down to the write to twsi_control_flags which is putting the NOR flash into status mode leading to the hang when the next instruction is executed.
I'm not sure how we haven't hit this before. In v2015.04 the same code path is executed but somehow no hang occurs. This code hasn't changed much between v2015.04 and v2015.10 and certainly not in any way that would change this behaviour. Presumably _something_ else has changed in a way that is affecting this behaviour but so far I haven't been able to narrow this down to a particular change.
Chris Packham (1): i2c: mvtwsi: avoid writing to twsi_control_flags prior to relocation
drivers/i2c/mvtwsi.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)