The content of this topic has been archived on 9 Apr 2018. There are no obvious gaps in this topic, but there may still be some posts missing at the end.
RB411R board running OpenWrt Trunk r19488 on basis of Linux version 2.6.32.7 shows while booting:
CPU revision is: 00019374 (MIPS 24Kc)
Atheros AR7130 rev 2, CPU:300.000 MHz, AHB:150.000 MHz, DDR:300.000 MHz
and a bit later:
Calibrating delay loop... 199.88 BogoMIPS (lpj=999424)
It would appear the CPU is running at 200 MHz despite it supposedly being a 300 MHz type.
Can this be changed, and if so where ?
This is in line what I am seeing on the Routerstation Pro. It has a AR7161 @ 720 Mhz, and gets ~480 BogoMIPS, which is also about 2/3 of its nominal speed.
have checked some other boards as well:
RouterStation boot messages:
Linux version 2.6.31.6
CPU revision is: 00019374 (MIPS 24Kc)
Atheros AR7161 rev 2, CPU:680.000 MHz, AHB:170.000 MHz, DDR:340.000 MHz
Calibrating delay loop... 452.19 BogoMIPS (lpj=2260992)
(66.5 %)
LS-SR71 boot messages (original ubnt firmware; also AR7161 cpu):
Linux version 2.6.15
CPU revision is: 00019374
Calibrating delay loop... 451.58 BogoMIPS (lpj=225792)
(66.4%)
But my initial idea that this BogoMIPS should reflect 1:1 the clock frequency is wrong if I may believe wikipedia; it was just accidental that I have seen 1:1 ratios before with other CPUs. For a cpu architecture there exists a ratio beteen the speed at which the simplest of instructions can be processed (do nothing) and the clock speed. So the 2/3 value we find is probably characteristic for this type of CPU.
The discussion might have continued from here.