KVM: PPC: Enable MMIO to do 64 bits, fprs and qprs

Right now MMIO access can only happen for GPRs and is at most 32 bit wide.
That's actually enough for almost all types of hardware out there.

Unfortunately, the guest I was using used FPU writes to MMIO regions, so
it ended up writing 64 bit MMIOs using FPRs and QPRs.

So let's add code to handle those odd cases too.

Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>

3 files changed, 30 insertions, 3 deletions

diff --git a/arch/powerpc/include/asm/kvm.h b/arch/powerpc/include/asm/kvm.h
index 81f3b0b5601..19bae31202c 100644
--- a/arch/powerpc/include/asm/kvm.h
+++ b/arch/powerpc/include/asm/kvm.h
@@ -77,4 +77,11 @@ struct kvm_debug_exit_arch {
 struct kvm_guest_debug_arch {
 };
 
+#define KVM_REG_MASK		0x001f
+#define KVM_REG_EXT_MASK	0xffe0
+#define KVM_REG_GPR		0x0000
+#define KVM_REG_FPR		0x0020
+#define KVM_REG_QPR		0x0040
+#define KVM_REG_FQPR		0x0060
+
 #endif /* __LINUX_KVM_POWERPC_H */
diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h
index e2642829e43..c011170f572 100644
--- a/arch/powerpc/include/asm/kvm_ppc.h
+++ b/arch/powerpc/include/asm/kvm_ppc.h
@@ -49,7 +49,7 @@ extern int kvmppc_handle_load(struct kvm_run *run, struct kvm_vcpu *vcpu,
                               unsigned int rt, unsigned int bytes,
                               int is_bigendian);
 extern int kvmppc_handle_store(struct kvm_run *run, struct kvm_vcpu *vcpu,
-                               u32 val, unsigned int bytes, int is_bigendian);
+                               u64 val, unsigned int bytes, int is_bigendian);
 
 extern int kvmppc_emulate_instruction(struct kvm_run *run,
                                       struct kvm_vcpu *vcpu);
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index 297fcd2ff7d..b7858b1e15e 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -278,7 +278,7 @@ static void kvmppc_complete_dcr_load(struct kvm_vcpu *vcpu,
 static void kvmppc_complete_mmio_load(struct kvm_vcpu *vcpu,
                                       struct kvm_run *run)
 {
-	ulong gpr;
+	u64 gpr;
 
 	if (run->mmio.len > sizeof(gpr)) {
 		printk(KERN_ERR "bad MMIO length: %d\n", run->mmio.len);
@@ -287,6 +287,7 @@ static void kvmppc_complete_mmio_load(struct kvm_vcpu *vcpu,
 
 	if (vcpu->arch.mmio_is_bigendian) {
 		switch (run->mmio.len) {
+		case 8: gpr = *(u64 *)run->mmio.data; break;
 		case 4: gpr = *(u32 *)run->mmio.data; break;
 		case 2: gpr = *(u16 *)run->mmio.data; break;
 		case 1: gpr = *(u8 *)run->mmio.data; break;
@@ -301,6 +302,24 @@ static void kvmppc_complete_mmio_load(struct kvm_vcpu *vcpu,
 	}
 
 	kvmppc_set_gpr(vcpu, vcpu->arch.io_gpr, gpr);
+
+	switch (vcpu->arch.io_gpr & KVM_REG_EXT_MASK) {
+	case KVM_REG_GPR:
+		kvmppc_set_gpr(vcpu, vcpu->arch.io_gpr, gpr);
+		break;
+	case KVM_REG_FPR:
+		vcpu->arch.fpr[vcpu->arch.io_gpr & KVM_REG_MASK] = gpr;
+		break;
+	case KVM_REG_QPR:
+		vcpu->arch.qpr[vcpu->arch.io_gpr & KVM_REG_MASK] = gpr;
+		break;
+	case KVM_REG_FQPR:
+		vcpu->arch.fpr[vcpu->arch.io_gpr & KVM_REG_MASK] = gpr;
+		vcpu->arch.qpr[vcpu->arch.io_gpr & KVM_REG_MASK] = gpr;
+		break;
+	default:
+		BUG();
+	}
 }
 
 int kvmppc_handle_load(struct kvm_run *run, struct kvm_vcpu *vcpu,
@@ -324,7 +343,7 @@ int kvmppc_handle_load(struct kvm_run *run, struct kvm_vcpu *vcpu,
 }
 
 int kvmppc_handle_store(struct kvm_run *run, struct kvm_vcpu *vcpu,
-                        u32 val, unsigned int bytes, int is_bigendian)
+                        u64 val, unsigned int bytes, int is_bigendian)
 {
 	void *data = run->mmio.data;
 
@@ -342,6 +361,7 @@ int kvmppc_handle_store(struct kvm_run *run, struct kvm_vcpu *vcpu,
 	/* Store the value at the lowest bytes in 'data'. */
 	if (is_bigendian) {
 		switch (bytes) {
+		case 8: *(u64 *)data = val; break;
 		case 4: *(u32 *)data = val; break;
 		case 2: *(u16 *)data = val; break;
 		case 1: *(u8  *)data = val; break;