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    x86: force timer broadcast on late AMD C1E detection · 89039b37
    Thomas Gleixner authored
    
    
    The 64bit SMP bootup is slightly different to the 32bit one. It enables
    the boot CPU local APIC timer before all CPUs are brought up. Some AMD C1E
    systems have the C1E feature flag only set in the secondary CPU. Due to
    the early enable of the boot CPU local APIC timer the APIC timer is
    registered as a fully functional device. When we detect the wreckage during
    the bringup of the secondary CPU, we need to force the boot CPU into
    broadcast mode. 
    
    Check the C1E caused APIC timer disable, when the secondary APIC timer is
    initialized. If the boot CPU APIC timer was registered as a functional
    clock event device, then fix this up and utilize the
    CLOCK_EVT_NOTIFY_BROADCAST_FORCE mechanism to force the already
    registered boot CPU APIC timer into broadcast mode.
    
    Tested by force injecting the failure mode.
    
    Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
    89039b37