[PATCH 06/15] ppc: spapr: Implement nested PAPR hcall - H_GUEST_GET_CAPABILITIES

[Harsh Prateek Bora]

This patch implements nested PAPR hcall H_GUEST_GET_CAPABILITIES and
also enables registration of nested PAPR hcalls whenever an L0 is
launched with cap-nested-papr=true. The common registration routine
shall be used by future patches for registration of related hcall
support
being added. This hcall is used by L1 kernel to get the set of guest
capabilities that are supported by L0 (Qemu TCG).

Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
---
 hw/ppc/spapr_caps.c           |  1 +
 hw/ppc/spapr_nested.c         | 35 +++++++++++++++++++++++++++++++++++
 include/hw/ppc/spapr_nested.h |  6 ++++++
 3 files changed, 42 insertions(+)

diff --git a/hw/ppc/spapr_caps.c b/hw/ppc/spapr_caps.c
index d3b9f107aa..cbe53a79ec 100644
--- a/hw/ppc/spapr_caps.c
+++ b/hw/ppc/spapr_caps.c
@@ -511,6 +511,7 @@ static void cap_nested_papr_apply(SpaprMachineState *spapr,
             return;
         }
         spapr->nested.api = NESTED_API_PAPR;
+        spapr_register_nested_phyp();
     } else if (kvm_enabled()) {
         /*
          * this gets executed in L1 qemu when L2 is launched,
diff --git a/hw/ppc/spapr_nested.c b/hw/ppc/spapr_nested.c
index a669470f1a..37f3a49be2 100644
--- a/hw/ppc/spapr_nested.c
+++ b/hw/ppc/spapr_nested.c
@@ -6,6 +6,7 @@
 #include "hw/ppc/spapr.h"
 #include "hw/ppc/spapr_cpu_core.h"
 #include "hw/ppc/spapr_nested.h"
+#include "cpu-models.h"
 
 #ifdef CONFIG_TCG
 #define PRTS_MASK      0x1f
@@ -375,6 +376,29 @@ void spapr_exit_nested(PowerPCCPU *cpu, int excp)
     address_space_unmap(CPU(cpu)->as, regs, len, len, true);
 }
 
+static target_ulong h_guest_get_capabilities(PowerPCCPU *cpu,
+                                             SpaprMachineState *spapr,
+                                             target_ulong opcode,
+                                             target_ulong *args)
+{
+    CPUPPCState *env = &cpu->env;
+    target_ulong flags = args[0];
+
+    if (flags) { /* don't handle any flags capabilities for now */
+        return H_PARAMETER;
+    }
+
+    if ((env->spr[SPR_PVR] & CPU_POWERPC_POWER_SERVER_MASK) ==
+        (CPU_POWERPC_POWER9_BASE))
+        env->gpr[4] = H_GUEST_CAPABILITIES_P9_MODE;
+
+    if ((env->spr[SPR_PVR] & CPU_POWERPC_POWER_SERVER_MASK) ==
+        (CPU_POWERPC_POWER10_BASE))
+        env->gpr[4] = H_GUEST_CAPABILITIES_P10_MODE;
+
+    return H_SUCCESS;
+}
+
 void spapr_register_nested(void)
 {
     spapr_register_hypercall(KVMPPC_H_SET_PARTITION_TABLE, h_set_ptbl);
@@ -382,6 +406,12 @@ void spapr_register_nested(void)
     spapr_register_hypercall(KVMPPC_H_TLB_INVALIDATE, h_tlb_invalidate);
     spapr_register_hypercall(KVMPPC_H_COPY_TOFROM_GUEST, h_copy_tofrom_guest);
 }
+
+void spapr_register_nested_phyp(void)
+{
+    spapr_register_hypercall(H_GUEST_GET_CAPABILITIES, 
h_guest_get_capabilities);
+}
+
 #else
 void spapr_exit_nested(PowerPCCPU *cpu, int excp)
 {
@@ -392,4 +422,9 @@ void spapr_register_nested(void)
 {
     /* DO NOTHING */
 }
+
+void spapr_register_nested_phyp(void)
+{
+    /* DO NOTHING */
+}
 #endif
diff --git a/include/hw/ppc/spapr_nested.h b/include/hw/ppc/spapr_nested.h
index f8db31075b..ce198e9f70 100644
--- a/include/hw/ppc/spapr_nested.h
+++ b/include/hw/ppc/spapr_nested.h
@@ -189,6 +189,11 @@
 /* End of list of Guest State Buffer Element IDs */
 #define GSB_LAST                GSB_VCPU_SPR_ASDR
 
+/* Bit masks to be used in nested PAPR API */
+#define H_GUEST_CAPABILITIES_COPY_MEM 0x8000000000000000
+#define H_GUEST_CAPABILITIES_P9_MODE  0x4000000000000000
+#define H_GUEST_CAPABILITIES_P10_MODE 0x2000000000000000
+
 typedef struct SpaprMachineStateNestedGuest {
     unsigned long vcpus;
     struct SpaprMachineStateNestedGuestVcpu *vcpu;
@@ -331,6 +336,7 @@ struct nested_ppc_state {
 };
 
 void spapr_register_nested(void);
+void spapr_register_nested_phyp(void);
 void spapr_exit_nested(PowerPCCPU *cpu, int excp);
 
 #endif /* HW_SPAPR_NESTED_H */
-- 
2.39.3