• Suraj Jitindar Singh's avatar
    powerpc: Update to new option-vector-5 format for CAS · 014d02cb
    Suraj Jitindar Singh authored
    On POWER9 the ibm,client-architecture-support (CAS) negotiation process
    has been updated to change how the host to guest negotiation is done for
    the new hash/radix mmu as well as the nest mmu, process tables and guest
    translation shootdown (GTSE).
    
    This is documented in the unreleased PAPR ACR "CAS option vector
    additions for P9".
    
    The host tells the guest which options it supports in
    ibm,arch-vec-5-platform-support. The guest then chooses a subset of these
    to request in the CAS call and these are agreed to in the
    ibm,architecture-vec-5 property of the chosen node.
    
    Thus we read ibm,arch-vec-5-platform-support and make our selection before
    calling CAS. We then parse the ibm,architecture-vec-5 property of the
    chosen node to check whether we should run as hash or radix.
    
    ibm,arch-vec-5-platform-support format:
    
    index value pairs: <index, val> ... <index, val>
    
    index: Option vector 5 byte number
    val:   Some representation of supported values
    Signed-off-by: default avatarSuraj Jitindar Singh <sjitindarsingh@gmail.com>
    Acked-by: default avatarPaul Mackerras <paulus@ozlabs.org>
    [mpe: Don't print about unknown options, be consistent with OV5_FEAT]
    Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
    014d02cb
prom.h 6.98 KB