powerpc/pseries: drop RTAS-based timebase synchronization

The pseries platform has been LPAR-only for several generations, and
the PAPR spec:

* Guarantees that timebase synchronization is performed by
  the platform ("The timebase registers are synchronized by the
  platform before CPUs are given to the OS" - 7.3.8 SMP Support).

* Completely omits the RTAS freeze-time-base and thaw-time-base RTAS
  functions, which are CHRP artifacts.

This code is effectively unused on currently supported models, so drop
it.

Signed-off-by: Nathan Lynch <nathanl@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230125-b4-powerpc-rtas-queue-v3-7-26929c8cce78@linux.ibm.com

diff --git a/arch/powerpc/platforms/pseries/smp.c b/arch/powerpc/platforms/pseries/smp.c
index fd2174edfa1dcbaff9f85fdb05568a40563a0438..2bcfee86ff87c1ec152650f5cecded32206963c6 100644 (file)
--- a/arch/powerpc/platforms/pseries/smp.c
+++ b/arch/powerpc/platforms/pseries/smp.c
@@ -278,11 +278,5 @@ void __init smp_init_pseries(void)
                cpumask_clear_cpu(boot_cpuid, of_spin_mask);
        }
 
-       /* Non-lpar has additional take/give timebase */
-       if (rtas_token("freeze-time-base") != RTAS_UNKNOWN_SERVICE) {
-               smp_ops->give_timebase = rtas_give_timebase;
-               smp_ops->take_timebase = rtas_take_timebase;
-       }
-
        pr_debug(" <- smp_init_pSeries()\n");
 }