spapr: CPU hotplug support

Set up device tree entries for the hotplugged CPU core and use the
exising RTAS event logging infrastructure to send CPU hotplug notification
to the guest.

Signed-off-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

1 files changed, 24 insertions, 0 deletions

diff --git a/hw/ppc/spapr_rtas.c b/hw/ppc/spapr_rtas.c
index 43e2c684fd..dc058e512b 100644
--- a/hw/ppc/spapr_rtas.c
+++ b/hw/ppc/spapr_rtas.c
@@ -36,6 +36,7 @@
 
 #include "hw/ppc/spapr.h"
 #include "hw/ppc/spapr_vio.h"
+#include "hw/ppc/ppc.h"
 #include "qapi-event.h"
 #include "hw/boards.h"
 
@@ -164,6 +165,27 @@ static void rtas_query_cpu_stopped_state(PowerPCCPU *cpu_,
     rtas_st(rets, 0, RTAS_OUT_PARAM_ERROR);
 }
 
+/*
+ * Set the timebase offset of the CPU to that of first CPU.
+ * This helps hotplugged CPU to have the correct timebase offset.
+ */
+static void spapr_cpu_update_tb_offset(PowerPCCPU *cpu)
+{
+    PowerPCCPU *fcpu = POWERPC_CPU(first_cpu);
+
+    cpu->env.tb_env->tb_offset = fcpu->env.tb_env->tb_offset;
+}
+
+static void spapr_cpu_set_endianness(PowerPCCPU *cpu)
+{
+    PowerPCCPU *fcpu = POWERPC_CPU(first_cpu);
+    PowerPCCPUClass *pcc = POWERPC_CPU_GET_CLASS(fcpu);
+
+    if (!pcc->interrupts_big_endian(fcpu)) {
+        cpu->env.spr[SPR_LPCR] |= LPCR_ILE;
+    }
+}
+
 static void rtas_start_cpu(PowerPCCPU *cpu_, sPAPRMachineState *spapr,
                            uint32_t token, uint32_t nargs,
                            target_ulong args,
@@ -200,6 +222,8 @@ static void rtas_start_cpu(PowerPCCPU *cpu_, sPAPRMachineState *spapr,
         env->nip = start;
         env->gpr[3] = r3;
         cs->halted = 0;
+        spapr_cpu_set_endianness(cpu);
+        spapr_cpu_update_tb_offset(cpu);
 
         qemu_cpu_kick(cs);