KVM: PPC: 440: Implement mfdcrx

We need mfdcrx to execute properly on 460 cores.

Signed-off-by: Alexander Graf <agraf@suse.de>

1 files changed, 43 insertions, 31 deletions

diff --git a/arch/powerpc/kvm/44x_emulate.c b/arch/powerpc/kvm/44x_emulate.c
index 3843a75e3e98..1a793c4c4a67 100644
--- a/arch/powerpc/kvm/44x_emulate.c
+++ b/arch/powerpc/kvm/44x_emulate.c
@@ -27,6 +27,7 @@
 #include "booke.h"
 #include "44x_tlb.h"
 
+#define XOP_MFDCRX  259
 #define XOP_MFDCR   323
 #define XOP_MTDCRX  387
 #define XOP_MTDCR   451
@@ -51,6 +52,43 @@ static int emulate_mtdcr(struct kvm_vcpu *vcpu, int rs, int dcrn)
         }
 }
 
+static int emulate_mfdcr(struct kvm_vcpu *vcpu, int rt, int dcrn)
+{
+        /* The guest may access CPR0 registers to determine the timebase
+         * frequency, and it must know the real host frequency because it
+         * can directly access the timebase registers.
+         *
+         * It would be possible to emulate those accesses in userspace,
+         * but userspace can really only figure out the end frequency.
+         * We could decompose that into the factors that compute it, but
+         * that's tricky math, and it's easier to just report the real
+         * CPR0 values.
+         */
+        switch (dcrn) {
+        case DCRN_CPR0_CONFIG_ADDR:
+                kvmppc_set_gpr(vcpu, rt, vcpu->arch.cpr0_cfgaddr);
+                break;
+        case DCRN_CPR0_CONFIG_DATA:
+                local_irq_disable();
+                mtdcr(DCRN_CPR0_CONFIG_ADDR,
+                          vcpu->arch.cpr0_cfgaddr);
+                kvmppc_set_gpr(vcpu, rt,
+                               mfdcr(DCRN_CPR0_CONFIG_DATA));
+                local_irq_enable();
+                break;
+        default:
+                vcpu->run->dcr.dcrn = dcrn;
+                vcpu->run->dcr.data =  0;
+                vcpu->run->dcr.is_write = 0;
+                vcpu->arch.io_gpr = rt;
+                vcpu->arch.dcr_needed = 1;
+                kvmppc_account_exit(vcpu, DCR_EXITS);
+                return EMULATE_DO_DCR;
+        }
+
+        return EMULATE_DONE;
+}
+
 int kvmppc_core_emulate_op(struct kvm_run *run, struct kvm_vcpu *vcpu,
                            unsigned int inst, int *advance)
 {
@@ -68,38 +106,12 @@ int kvmppc_core_emulate_op(struct kvm_run *run, struct kvm_vcpu *vcpu,
                 switch (get_xop(inst)) {
 
                 case XOP_MFDCR:
-                        /* The guest may access CPR0 registers to determine the timebase
-                         * frequency, and it must know the real host frequency because it
-                         * can directly access the timebase registers.
-                         *
-                         * It would be possible to emulate those accesses in userspace,
-                         * but userspace can really only figure out the end frequency.
-                         * We could decompose that into the factors that compute it, but
-                         * that's tricky math, and it's easier to just report the real
-                         * CPR0 values.
-                         */
-                        switch (dcrn) {
-                        case DCRN_CPR0_CONFIG_ADDR:
-                                kvmppc_set_gpr(vcpu, rt, vcpu->arch.cpr0_cfgaddr);
-                                break;
-                        case DCRN_CPR0_CONFIG_DATA:
-                                local_irq_disable();
-                                mtdcr(DCRN_CPR0_CONFIG_ADDR,
-                                          vcpu->arch.cpr0_cfgaddr);
-                                kvmppc_set_gpr(vcpu, rt,
-                                               mfdcr(DCRN_CPR0_CONFIG_DATA));
-                                local_irq_enable();
-                                break;
-                        default:
-                                run->dcr.dcrn = dcrn;
-                                run->dcr.data =  0;
-                                run->dcr.is_write = 0;
-                                vcpu->arch.io_gpr = rt;
-                                vcpu->arch.dcr_needed = 1;
-                                kvmppc_account_exit(vcpu, DCR_EXITS);
-                                emulated = EMULATE_DO_DCR;
-                        }
+                        emulated = emulate_mfdcr(vcpu, rt, dcrn);
+                        break;
 
+                case XOP_MFDCRX:
+                        emulated = emulate_mfdcr(vcpu, rt,
+                                        kvmppc_get_gpr(vcpu, ra));
                         break;
 
                 case XOP_MTDCR: