Hi Nitin,
Look`s like SpeedStepping in action - correct behavior while on idle. Please put more stress on CPU and recheck - It should jump back to 2200
BR, Mariusz
-----Original Message----- From: nitin.ramesh.singh@gmail.com nitin.ramesh.singh@gmail.com Sent: czwartek, 23 kwietnia 2020 14:36 To: coreboot@coreboot.org Subject: [coreboot] Regarding Intel CPU frequency.
Hi,
I am using coreboot to boot Denverton cpu (CPU C3558) based board.
I can see that the cpu frequency is set to the correct value i.e. "2200 Mhz" under the coreboot logs. . " CPU #3 initialized bsp_do_flight_plan done after 146 msecs. cpu: frequency set to 2200 "
Later when I check the frequency reading under linux (kernel version 4.19) , It comes out as 800 Mz:
model name : Intel(R) Atom(TM) CPU C3558 @ 2.20GHz stepping : 1 microcode : 0x24 cpu MHz : 800.000
When I reprogram the board with BIOS, the cpu frequency gets reflected correctly (i.e. 2200 MHz) with the same kernel image.
I have also tried out the different Grub command line options like disabling the pstate, and idle state e.t.c, but the end result remains same.
Can anyone please provide me some suggestions. Is there is any cpu specific settings which needs to enabled under coreboot or with Intel-FSP ?
Thanks, Nitin. _______________________________________________ coreboot mailing list -- coreboot@coreboot.org To unsubscribe send an email to coreboot-leave@coreboot.org -------------------------------------------------------------- Intel Research and Development Ireland Limited Registered in Ireland Registered Office: Collinstown Industrial Park, Leixlip, County Kildare Registered Number: 308263
This e-mail and any attachments may contain confidential material for the sole use of the intended recipient(s). Any review or distribution by others is strictly prohibited. If you are not the intended recipient, please contact the sender and delete all copies.