My system hosts 4x clusters, each with 4x cpus A57 connected through interconnect CCN504. I have a special case in which I need to reset L2 sybsystem (L2 is 2MB in my case) from inside SPL Uboot running from a static memory. The memory is attributed to Normal Non-Cachable and is behind the HN-I that converts the CCN transacations to AXI4. SPL Uboot is being run on a cpu0.
Can I reset the L2 subsystem in such a scenario with a single cpu0 on?
I mean we have a dynamic power management on the system through PSCI but in there the last cpu in a clusters powers down the L2 and the first brings L2 up and in there cpu0 never goes for reset.
Thanks,
Marek
I have experimented bit more and: I have came across "hold l2" reg (that should go to nL2RESET reset signal) that should put the L2 subsystem into reset. When I issue a reset to the cluster my cpu is in I get a board hang, but when I do it for another cluster all seem fine.