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  • 树莓派4B的CPU系统里查到为BCM2835而非BCM2711

    树莓派4B采用四核64位的ARM Cortex-A72架构CPU,型号为博通BCM2711 SoC。2711是个64位的四核,而2835是多年前的32位单核CPU。

    查看当前芯片版本,显示为4核心,但是芯片名字却是BCM2835,这是一个很老的芯片。

    在树莓派zero和1上使用的,新的树莓派4B是BCM2711,拿起板子我能明显看到 芯片上的丝印字,为什么cpuinfo命令查出来的是错误的呢?

    pi@raspberrypi:/proc/cpu $ cat /proc/cpuinfo

    processor : 0

    model name : ARMv7 Processor rev 3 (v7l)

    BogoMIPS : 108.00

    Features : half thumb fastmult vfp edsp neon vfpv3 tls vfpv4 idiva idivt vfpd32 lpae evtstrm crc32

    CPU implementer : 0x41

    CPU architecture: 7

    CPU variant : 0x0

    CPU part : 0xd08

    CPU revision : 3

     

    processor : 1

    model name : ARMv7 Processor rev 3 (v7l)

    BogoMIPS : 108.00

    Features : half thumb fastmult vfp edsp neon vfpv3 tls vfpv4 idiva idivt vfpd32 lpae evtstrm crc32

    CPU implementer : 0x41

    CPU architecture: 7

    CPU variant : 0x0

    CPU part : 0xd08

    CPU revision : 3

     

    processor : 2

    model name : ARMv7 Processor rev 3 (v7l)

    BogoMIPS : 108.00

    Features : half thumb fastmult vfp edsp neon vfpv3 tls vfpv4 idiva idivt vfpd32 lpae evtstrm crc32

    CPU implementer : 0x41

    CPU architecture: 7

    CPU variant : 0x0

    CPU part : 0xd08

    CPU revision : 3

     

    processor : 3

    model name : ARMv7 Processor rev 3 (v7l)

    BogoMIPS : 108.00

    Features : half thumb fastmult vfp edsp neon vfpv3 tls vfpv4 idiva idivt vfpd32 lpae evtstrm crc32

    CPU implementer : 0x41

    CPU architecture: 7

    CPU variant : 0x0

    CPU part : 0xd08

    CPU revision : 3

     

    Hardware : BCM2835

    Revision : b03111

    Serial : 10000000eb0168e0

    Model : Raspberry Pi 4 Model B Rev 1.1

    Gordon大佬回复如下,大意是内核只许设置1个值,如果设置不同的值就要改代码,这会导致上游集成更加麻烦。建议查版本用cat /proc/device-tree/model来看。

    Gordon Hollingworth PhD

    Raspberry Pi - Director of Software Engineering

    https://www.raspberrypi.org/forums/viewtopic.php?p=1190349

     

    this, as 6by9 indicated, is due to the fact that the upstream ARM kernel only allows us to set a single value for our devices.

    If we wanted to have multiple different values it would require that we edit the code (which in general we prefer not to do because is causes problems for us wen integrating changes from upstream).i've asked Phil to change this to instead return "BCM28xx" to indicate that the kernel is specifically for the BCM2805/6/7 silicon.if you'd like to find out the model of the computer you should use the device tree instead a la:

    pi@raspberrypi:~ $ cat /proc/device-tree/model

    Raspberry Pi 3 Model B Rev 1.2

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  • 原文地址:https://www.cnblogs.com/pingwen/p/13455849.html
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