On Sat, Jun 21, 2014 at 2:02 PM, Pavel Machek pavel@ucw.cz wrote:
Hi!
AFAICT, pstate file will contain something like
07: core 100 MHz memory 123 MHz * 08: core 100-200 MHz memory 123 MHz
...which does not look exactly like one-value-per-file, and I'm pretty sure userspace will get it wrong if it tries to parse it. Plus, I don't see required documentation in Documentation/ABI.
Should we disable it for now, so that userspace does not start depending on it and we'll not have to maintain it forever?
I guess better interface would be something like
pstate/07/core_clock_min core_clock_max memory_clock_min memory_clock_max
and then pstate/active containing just the number of active state?
Thanks, Pavel
PS: I have no nvidia, got the news at
http://www.phoronix.com/scan.php?page=article&item=nouveau_try_linux316&...
FTR, this file has been in place since 3.13, and there was a different file before it (performance_levels), with a comparable format since much earlier (definitely 3.8, probably earlier). I think it's meant a lot more for people looking at it and echo'ing stuff to it to modify the levels (where supported), than for programs parsing it. Perhaps sysfs is the wrong place for this -- what is the right place? debugfs?
-ilia