LWN: Comments on "CentOS and ARM"

CentOS and ARM

pabs — Wed, 28 Jun 2017 16:22:12 +0000

The primary processor on RPi systems is not an ARM processor. The system starts the VC4 processor first, which then runs the proprietary firmware that starts the ARM processor etc. The link above is libre firmware for the VC4 processor.

CentOS and ARM

drag — Wed, 28 Jun 2017 15:42:39 +0000

That would be unfortunate as the bootloader in ARM systems traditionally formed the initial 'firmware' that bootstrapped the system.

This would me we are going backwards.

CentOS and ARM

pbonzini — Wed, 28 Jun 2017 15:33:32 +0000

I suspect that would be closed firmware -> U-Boot -> Linux, with U-Boot providing the UEFI runtime services instead of the UEFI firmware you see in x86 machines or ARM servers.

Benchmarks

gmatht — Wed, 28 Jun 2017 14:52:57 +0000

Now that these things are out, I was curious as to whether they have demonstrated better performance per watt. The only performance per watt benchmark I could find was from people who couldn't get CPU frequency scaling to work, and didn't as good performance per watt as Intel. [1]

On the other hand the 96 Core Cavium ThunderX machines outperforms an Amazon c4.4xlarge instance at some tasks [2]. Packet offers them at 50c vs ~75c for the Amazon c4.4xlarge ondemand hourly rate, so they have demonstrated better performance per dollar in at least some contexts. (E.g. if you like the ondemand pricing model. Amazon's spot price is usually much lower.)

[1] http://www.anandtech.com/show/10353/investigating-cavium-...
[2] https://www.servethehome.com/exclusive-first-cavium-thund...

CentOS and ARM

ardbiesheuvel — Wed, 28 Jun 2017 08:45:49 +0000

If anyone is interested in collaborating on a true UEFI port for Raspberry Pi3:
http://www.workofard.com/2017/02/uefi-on-the-pi/

CentOS and ARM

johnjones — Wed, 28 Jun 2017 07:24:42 +0000

"The 64-bit Raspberry Pi 3 (RPi3) will ostensibly be supported in three months or so, he said, once the U-Boot bootloader gets UEFI support."

I hope the firmware is open like : https://github.com/christinaa/rpi-open-firmware

the minus marks against the raspberry pi is the closed broadcom firmware that you can not debug