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We can examine /proc/cpuinfo on Intel and ARM machines to learn cpu features, like AES and SHA. I need to do the same for PowerPC under both AIX and Linux.

Testing with Linux is shown below. The output is produced by GCC112 on the compile farm.

$ cat /proc/cpuinfo processor : 0 cpu : POWER8E (raw), altivec supported clock : 2061.000000MHz revision : 2.1 (pvr 004b 0201) ... processor : 159 cpu : POWER8E (raw), altivec supported clock : 2061.000000MHz revision : 2.1 (pvr 004b 0201) timebase : 512000000 platform : PowerNV model : 8247-22L machine : PowerNV 8247-22L firmware : OPAL v3

GCC112 is a Power 8 machine. I should be seeing flags like VMX, AES, SHA, PMULL, etc. VMX is roughly the PowerPC equivalent to Intel SSE and ARM NEON.

I've found some related discussions like /proc/cpuinfo on comp.os.linux.powerpc. I also found What do we check on a new system?, but it lacks useful details like cpu features. Finally, there's a related question at What do the flags in /proc/cpuinfo mean?, but it does not discuss PowerPC.

GCC appears to provide the information to C programs through its use of built-ins. For example, there's a vsx test and a vcrypto test. The problem is, I'm working from a Bash script and not a C program.

I also don't know what to use for AIX. AIX is available at GCC119 on the compile farm.

How do I get the PowerPC cpu features on AIX and Linux?

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    You might get some info from lscpu on Linux, and lscfg -v on AIX. Commented Sep 9, 2017 at 18:16
  • Thanks @meuh - No joy. Output available at PowerPC CPU information. Commented Sep 9, 2017 at 19:26
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    I don't know about ARM, but SSE is an optional extension on x86, while everything you've mentioned for POWER is required by all POWER8 chips Commented Sep 9, 2017 at 20:52
  • I think we've covered the Linux case at stackoverflow.com/questions/46144668/… , do you want to edit this one to be more specific to AIX? Commented Sep 12, 2017 at 1:34

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I am not sure why /proc/cpuinfo or lscpu does not reveal flag information. I have found the list of flags known to the linux kernel https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git/tree/arch/powerpc/include/asm/cputable.h?id=refs/tags/v4.9

I've just found that you can lookup ELF auxiliary vectors which will show you some hardware capabilities.

$ LD_SHOW_AUXV=1 /bin/true AT_SYSINFO_EHDR: 0x7ffdcd0e6000 AT_HWCAP: bfebfbff AT_PAGESZ: 4096 AT_CLKTCK: 100 AT_PHDR: 0x5591e6663040 AT_PHENT: 56 AT_PHNUM: 9 AT_BASE: 0x7f2ae4f79000 AT_FLAGS: 0x0 AT_ENTRY: 0x5591e6664670 AT_UID: 1000 AT_EUID: 1000 AT_GID: 1000 AT_EGID: 1000 AT_SECURE: 0 AT_RANDOM: 0x7ffdcd044399 AT_HWCAP2: 0x0 AT_EXECFN: /bin/true AT_PLATFORM: x86_64

^^ your AT_HWCAP will have flag info. Masked. I've seen samples on the Internet that have this entry decoded for you. I don't have access to ppc hardware to test on unfortunately.

lscpu should be available on AIX, perhaps it would show CPU flags?

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