spapr: Add ibm,processor-radix-AP-encodings to the device tree

Use the new ioctl, KVM_PPC_GET_RMMU_INFO, to fetch radix MMU
information from KVM and present the page encodings in the device tree
under ibm,processor-radix-AP-encodings. This provides page size
information to the guest which is necessary for it to use radix mode.

Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com>
[dwg: Compile fix for 32-bit targets, style nit fix]
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

hw/ppc/spapr.c

@@ -459,6 +459,8 @@ static void spapr_populate_cpu_dt(CPUState *cs, void *fdt, int offset,
     sPAPRDRConnector *drc;
     sPAPRDRConnectorClass *drck;
     int drc_index;
+    uint32_t radix_AP_encodings[PPC_PAGE_SIZES_MAX_SZ];
+    int i;
 
     drc = spapr_dr_connector_by_id(SPAPR_DR_CONNECTOR_TYPE_CPU, index);
     if (drc) {
@@ -544,6 +546,17 @@ static void spapr_populate_cpu_dt(CPUState *cs, void *fdt, int offset,
     _FDT(spapr_fixup_cpu_numa_dt(fdt, offset, cs));
 
     _FDT(spapr_fixup_cpu_smt_dt(fdt, offset, cpu, compat_smt));
+
+    if (pcc->radix_page_info) {
+        for (i = 0; i < pcc->radix_page_info->count; i++) {
+            radix_AP_encodings[i] =
+                cpu_to_be32(pcc->radix_page_info->entries[i]);
+        }
+        _FDT((fdt_setprop(fdt, offset, "ibm,processor-radix-AP-encodings",
+                          radix_AP_encodings,
+                          pcc->radix_page_info->count *
+                          sizeof(radix_AP_encodings[0]))));
+    }
 }
 
 static void spapr_populate_cpus_dt_node(void *fdt, sPAPRMachineState *spapr)

include/sysemu/kvm.h

@@ -527,5 +527,6 @@ int kvm_set_one_reg(CPUState *cs, uint64_t id, void *source);
  * Returns: 0 on success, or a negative errno on failure.
  */
 int kvm_get_one_reg(CPUState *cs, uint64_t id, void *target);
+struct ppc_radix_page_info *kvm_get_radix_page_info(void);
 int kvm_get_max_memslots(void);
 #endif

target/ppc/cpu-qom.h

@@ -197,6 +197,7 @@ typedef struct PowerPCCPUClass {
     int bfd_mach;
     uint32_t l1_dcache_size, l1_icache_size;
     const struct ppc_segment_page_sizes *sps;
+    struct ppc_radix_page_info *radix_page_info;
     void (*init_proc)(CPUPPCState *env);
     int  (*check_pow)(CPUPPCState *env);
     int (*handle_mmu_fault)(PowerPCCPU *cpu, vaddr eaddr, int rwx, int mmu_idx);

target/ppc/cpu.h

@@ -943,6 +943,10 @@ struct ppc_segment_page_sizes {
     struct ppc_one_seg_page_size sps[PPC_PAGE_SIZES_MAX_SZ];
 };
 
+struct ppc_radix_page_info {
+    uint32_t count;
+    uint32_t entries[PPC_PAGE_SIZES_MAX_SZ];
+};
 
 /*****************************************************************************/
 /* The whole PowerPC CPU context */

target/ppc/kvm.c

@@ -50,6 +50,7 @@
 #include "hw/ppc/spapr_cpu_core.h"
 #endif
 #include "elf.h"
+#include "sysemu/kvm_int.h"
 
 //#define DEBUG_KVM
 
@@ -333,6 +334,30 @@ static void kvm_get_smmu_info(PowerPCCPU *cpu, struct kvm_ppc_smmu_info *info)
     kvm_get_fallback_smmu_info(cpu, info);
 }
 
+struct ppc_radix_page_info *kvm_get_radix_page_info(void)
+{
+    KVMState *s = KVM_STATE(current_machine->accelerator);
+    struct ppc_radix_page_info *radix_page_info;
+    struct kvm_ppc_rmmu_info rmmu_info;
+    int i;
+
+    if (!kvm_check_extension(s, KVM_CAP_PPC_MMU_RADIX)) {
+        return NULL;
+    }
+    if (kvm_vm_ioctl(s, KVM_PPC_GET_RMMU_INFO, &rmmu_info)) {
+        return NULL;
+    }
+    radix_page_info = g_malloc0(sizeof(*radix_page_info));
+    radix_page_info->count = 0;
+    for (i = 0; i < PPC_PAGE_SIZES_MAX_SZ; i++) {
+        if (rmmu_info.ap_encodings[i]) {
+            radix_page_info->entries[i] = rmmu_info.ap_encodings[i];
+            radix_page_info->count++;
+        }
+    }
+    return radix_page_info;
+}
+
 static bool kvm_valid_page_size(uint32_t flags, long rampgsize, uint32_t shift)
 {
     if (!(flags & KVM_PPC_PAGE_SIZES_REAL)) {
@@ -2303,6 +2328,10 @@ static void kvmppc_host_cpu_class_init(ObjectClass *oc, void *data)
     if (icache_size != -1) {
         pcc->l1_icache_size = icache_size;
     }
+
+#if defined(TARGET_PPC64)
+    pcc->radix_page_info = kvm_get_radix_page_info();
+#endif /* defined(TARGET_PPC64) */
 }
 
 bool kvmppc_has_cap_epr(void)