qemu-x86_64 fails on A72 cores, but runs nice on A53 ones :)
#7
Smile 
(11-03-2018, 08:43 PM)guannais Wrote: Thanks for the performance advice [Image: smile.png]

Since "qemu" recompiles the code on the fly it may be a problem with the code generator for ARM. What is strange is that any A72 core should be binary compatible with any A53 one, just the armv8-a instruction set.

I was compiling with those flags:

Code:
CFLAGS="-march=armv8-a+simd+crc -mtune=cortex-a53 -mfix-cortex-a53-843419 -Os -pipe"
which I inherited from the setup of my Odroid-C2.

You welcome,

In theory,
Code:
-march=armv8-a+crypto+crc

Should enable: { "fp asimd" + "aes pmull sha1 sha2" } + { "crc32" }

But if you look into the definitions, that its not clear..
https://code.woboq.org/gcc/gcc/config/aa...s.def.html

So better do a explicit request:

Code:
-march=armv8-a+simd+crypto+crc
This should enable: "fp asimd" } + { "aes pmull sha1 sha2} + { "crc32" }
not sure about: evtstrm : kernel event stream using generic architected timer.. "

I think that landed in gcc 8.x, when you use crypto, it already add fp+simd, but I don't know if its already in stable version.. so I tell him explicitly to use the extensions..


Messages In This Thread
RE: qemu-x86_64 fails on A72 cores, but runs nice on A53 ones :) - by tuxd3v - 11-04-2018, 01:20 PM

Possibly Related Threads…
Thread Author Replies Views Last Post
  Linux Host - QEMU Android Guest? rik-shaw 0 2,042 07-09-2020, 08:02 PM
Last Post: rik-shaw
  qemu-x86_64 on rockpro? pfremm 3 4,754 05-14-2019, 07:36 AM
Last Post: Crrlow

Forum Jump:


Users browsing this thread: 1 Guest(s)