By adding idte, we are now able to expose the DAT-enhancement facility
to our guest. Also, properly simulate and expose the local-tlb-clearing
facility.

To improve the TLB flushing, we will have to remember each used table (or
at least a hash!) for each tlb entry, just like real HW does.

This allows me to start an upstream kernel (having also the mvcos patch
applied) compiled for z9 using:

qemu-system-s390x ... -cpu qemu,mvcos=on,stfle=on,ldisp=on,ldisphp=on,\
                           eimm=on,stckf=on,csst=on,csst2=on,ginste=on,\
                           exrl=on,dateh=on,ltlbc=on

Linux will detect the DAT-enhancement facility and use idte+cspg.

v1 -> v2:
- Allow to enable the DAT-enhancement facility.
- Fix wrong register in idte.
- Simply set m4 to zero in case local-tlb-clearing is not enabled.

David Hildenbrand (3):
  target/s390x: Indicate and check for local tlb clearing
  target/s390x: Improve heuristic for ipte
  target/s390x: Implement idte instruction

 target/s390x/cpu_models.c  |  2 ++
 target/s390x/helper.h      |  1 +
 target/s390x/insn-data.def |  2 ++
 target/s390x/mem_helper.c  | 78 +++++++++++++++++++++++++++++++++++++++-------
 target/s390x/translate.c   | 21 ++++++++++++-
 5 files changed, 92 insertions(+), 12 deletions(-)

-- 
2.9.4

On 06/22/2017 02:41 AM, David Hildenbrand wrote:
> By adding idte, we are now able to expose the DAT-enhancement facility
> to our guest. Also, properly simulate and expose the local-tlb-clearing
> facility.
> 
> To improve the TLB flushing, we will have to remember each used table (or
> at least a hash!) for each tlb entry, just like real HW does.
> 
> This allows me to start an upstream kernel (having also the mvcos patch
> applied) compiled for z9 using:
> 
> qemu-system-s390x ... -cpu qemu,mvcos=on,stfle=on,ldisp=on,ldisphp=on,\
>                             eimm=on,stckf=on,csst=on,csst2=on,ginste=on,\
>                             exrl=on,dateh=on,ltlbc=on
> 
> Linux will detect the DAT-enhancement facility and use idte+cspg.
> 
> v1 -> v2:
> - Allow to enable the DAT-enhancement facility.
> - Fix wrong register in idte.
> - Simply set m4 to zero in case local-tlb-clearing is not enabled.

Reviewed and applied to my target/s390x tree.


r~