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androidlinuxcpuprocfs

What is the difference between CPU Revision and Revision fields for arm processors?

Making a cat /proc/cpuinfo on Android returns this kind of output:

    Processor   : ARMv7 Processor rev 1 (v7l)
    processor   : 0
    BogoMIPS    : 38.00

    processor   : 1
    BogoMIPS    : 38.00

    processor   : 2
    BogoMIPS    : 38.00

    processor   : 3
    BogoMIPS    : 38.00

    Features    : swp half thumb fastmult vfp edsp neon vfpv3 tls vfpv4 idiva idivt vfpd32
    CPU implementer : 0x51
    CPU architecture: 7
    CPU variant : 0x2
    CPU part    : 0x06f
    CPU revision    : 1

    Hardware    : Qualcomm MSM8974PRO-AC
    Revision    : 0000
    Serial      : 0000000000000000

I do not find the meaning difference between those two fields:

  • CPU revision
  • Revision
Solution

  • CPU revision: It Indicates patch release or "minor revision". In your case it is 1. So this value is specific to your CPU. You can see that CPU revision is matching to Processor : ARMv7 Processor rev 1 (v7l)

    You can refer to attached image for the details of other filled as well.

    CPUID bit assignment

    Revision: It is related to your hardware (board) configuration. In your case your are using the Qualcomm hardware so revision number depends upon on it. It is independent of the CPU revision number.