How do I see which ARM CPU version I have?

Question

When compiling a package for the Pi I came across a message like this:

CFLAGS += -march=armv7-a -mtune=cortex-a8 -mfpu=neon -mfloat-abi=softfp #-mcpu=cortex-a8
and 
CFLAGS += -mtune=arm1176jzf-s -mfpu=vfp -mfloat-abi=hard

I know the difference between -march and -mtunu, but what is the difference between armv7-a and arm1176jzf-s? if I'm looking at a new Pi how do I know what flags and argument I should use?

score 58 · Accepted Answer · answered Oct 02 '13 at 21:48

58

At a command prompt, type

cat /proc/cpuinfo

to view CPU information.

The ARM11 chips use version 6 of the ARM instruction set, ARMv6. More recent chips from the ARM Cortex range like the Cortex A7, A8 etc all use the ARMv7 instruction set.

All Pi boards are shipped with an ARM11. The options on the second line look like a better fit for building software for the Pi. The first set of options appears to be for a newer generation of ARM chip.

answered Oct 02 '13 at 21:48

Steve

1,431
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https://stackoverflow.com/questions/76668304/confusion-regarding-arm-architecture-used-in-raspberry-pi-4-model-b/77732274#77732274 – Ershan Dec 29 '23 at 13:39

score 5 · Answer 2 · answered Oct 02 '13 at 20:15

5

Have you tried the uname command? Specifically uname -a

answered Oct 02 '13 at 20:15

STEJ

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5

1

This is giving me the compatible version, not the hardware version (higher) – steampowered Oct 03 '18 at 16:08
Yeah, this command only says aarch64... not that useful. – Alexis Wilke Mar 03 '21 at 03:16
Very usefull, because it tells me the version! Thanks! – musbach May 07 '23 at 15:56

score 3 · Answer 3 · answered Mar 29 '21 at 17:36

3

as STEJ's answer suggested, run uname -m.

If you have arm64 then it's 64bit and if you have armv7l, then it's 32bit

For more information: https://www.raspberrypi.org/forums/viewtopic.php?t=251721

answered Mar 29 '21 at 17:36

Aharon Ohayon

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armv7l is an armv7 instruction set 32 bit, arm64 is armv7 64 bit? – user3123159 Oct 04 '21 at 18:39

How do I see which ARM CPU version I have?

3 Answers3