Right now I am trying to disable the self-refresh of DRAM. Nice would be the possibility to disable it during runtime with some kind of kernel module.
What I have found so far:
Partial Array Self Refresh (PASR): A special mode where specific banks can be disabled. [
www.micron.com] this paper is giving a more detailed explanation.
This kind of DRAM is used, e.g., on the raspberry pi. Is there any option to control that function?
I also have found this article: [
lwn.net] It is describing some kind of framework, but I do not understand if it is usable and how. Does someone maybe have some code to try?
I also searched in the Linux kernel source code for PASR and had some findings. The most interesting one I think is this one:
drivers/memory/emif.h:338:#define PASR_MASK (0x7 << 24)
The problem is that this variable does not appear somewhere else. So there is no possibility to change it at runtime.
Thank you in advance!