• Paul Mackerras's avatar
    KVM: PPC: book3s_hv: Add support for PPC970-family processors · 9e368f29
    Paul Mackerras authored
    This adds support for running KVM guests in supervisor mode on those
    PPC970 processors that have a usable hypervisor mode.  Unfortunately,
    Apple G5 machines have supervisor mode disabled (MSR[HV] is forced to
    1), but the YDL PowerStation does have a usable hypervisor mode.
    
    There are several differences between the PPC970 and POWER7 in how
    guests are managed.  These differences are accommodated using the
    CPU_FTR_ARCH_201 (PPC970) and CPU_FTR_ARCH_206 (POWER7) CPU feature
    bits.  Notably, on PPC970:
    
    * The LPCR, LPID or RMOR registers don't exist, and the functions of
      those registers are provided by bits in HID4 and one bit in HID0.
    
    * External interrupts can be directed to the hypervisor, but unlike
      POWER7 they are masked by MSR[EE] in non-hypervisor modes and use
      SRR0/1 not HSRR0/1.
    
    * There is no virtual RMA (VRMA) mode; the guest must use an RMO
      (real mode offset) area.
    
    * The TLB entries are not tagged with the LPID, so it is necessary to
      flush the whole TLB on partition switch.  Furthermore, when switching
      partitions we have to ensure that no other CPU is executing the tlbie
      or tlbsync instructions in either the old or the new partition,
      otherwise undefined behaviour can occur.
    
    * The PMU has 8 counters (PMC registers) rather than 6.
    
    * The DSCR, PURR, SPURR, AMR, AMOR, UAMOR registers don't exist.
    
    * The SLB has 64 entries rather than 32.
    
    * There is no mediated external interrupt facility, so if we switch to
      a guest that has a virtual external interrupt pending but the guest
      has MSR[EE] = 0, we have to arrange to have an interrupt pending for
      it so that we can get control back once it re-enables interrupts.  We
      do that by sending ourselves an IPI with smp_send_reschedule after
      hard-disabling interrupts.
    Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
    Signed-off-by: default avatarAlexander Graf <agraf@suse.de>
    9e368f29
book3s_hv_interrupts.S 4.36 KB