powerpc, KVM: Split HVMODE_206 cpu feature bit into separate HV and architecture bits

This replaces the single CPU_FTR_HVMODE_206 bit with two bits, one to
indicate that we have a usable hypervisor mode, and another to indicate
that the processor conforms to PowerISA version 2.06.  We also add
another bit to indicate that the processor conforms to ISA version 2.01
and set that for PPC970 and derivatives.

Some PPC970 chips (specifically those in Apple machines) have a
hypervisor mode in that MSR[HV] is always 1, but the hypervisor mode
is not useful in the sense that there is no way to run any code in
supervisor mode (HV=0 PR=0).  On these processors, the LPES0 and LPES1
bits in HID4 are always 0, and we use that as a way of detecting that
hypervisor mode is not useful.

Where we have a feature section in assembly code around code that
only applies on POWER7 in hypervisor mode, we use a construct like

END_FTR_SECTION_IFSET(CPU_FTR_HVMODE | CPU_FTR_ARCH_206)

The definition of END_FTR_SECTION_IFSET is such that the code will
be enabled (not overwritten with nops) only if all bits in the
provided mask are set.

Note that the CPU feature check in __tlbie() only needs to check the
ARCH_206 bit, not the HVMODE bit, because __tlbie() can only get called
if we are running bare-metal, i.e. in hypervisor mode.

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>

4 files changed, 7 insertions, 5 deletions

diff --git a/arch/powerpc/kvm/book3s_64_mmu_hv.c b/arch/powerpc/kvm/book3s_64_mmu_hv.c
index 96ba96a16abf..212dcd8fc50b 100644
--- a/arch/powerpc/kvm/book3s_64_mmu_hv.c
+++ b/arch/powerpc/kvm/book3s_64_mmu_hv.c
@@ -128,7 +128,8 @@ void kvmppc_map_vrma(struct kvm *kvm, struct kvm_userspace_memory_region *mem)
 
 int kvmppc_mmu_hv_init(void)
 {
-	if (!cpu_has_feature(CPU_FTR_HVMODE_206))
+	if (!cpu_has_feature(CPU_FTR_HVMODE) ||
+	    !cpu_has_feature(CPU_FTR_ARCH_206))
 		return -EINVAL;
 	memset(lpid_inuse, 0, sizeof(lpid_inuse));
 	set_bit(mfspr(SPRN_LPID), lpid_inuse);
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 04da135cae61..dc70e7745ab3 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -443,7 +443,8 @@ int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
 
 int kvmppc_core_check_processor_compat(void)
 {
-	if (cpu_has_feature(CPU_FTR_HVMODE_206))
+	if (cpu_has_feature(CPU_FTR_HVMODE) &&
+	    cpu_has_feature(CPU_FTR_ARCH_206))
 		return 0;
 	return -EIO;
 }
diff --git a/arch/powerpc/kvm/book3s_hv_builtin.c b/arch/powerpc/kvm/book3s_hv_builtin.c
index 736df3cbbc55..7315ec6e8177 100644
--- a/arch/powerpc/kvm/book3s_hv_builtin.c
+++ b/arch/powerpc/kvm/book3s_hv_builtin.c
@@ -90,8 +90,8 @@ void kvm_rma_init(void)
 	void *rma;
 	struct page *pg;
 
-	/* Only do this on POWER7 in HV mode */
-	if (!cpu_has_feature(CPU_FTR_HVMODE_206))
+	/* Only do this in HV mode */
+	if (!cpu_has_feature(CPU_FTR_HVMODE))
 		return;
 
 	if (!kvm_rma_size || !kvm_rma_count)
diff --git a/arch/powerpc/kvm/book3s_segment.S b/arch/powerpc/kvm/book3s_segment.S
index 134501691ad0..aed32e517212 100644
--- a/arch/powerpc/kvm/book3s_segment.S
+++ b/arch/powerpc/kvm/book3s_segment.S
@@ -170,7 +170,7 @@ BEGIN_FTR_SECTION
 	mfspr	r4,SPRN_HSRR1
 	andi.	r12,r12,0x3ffd
 	b	2f
-END_FTR_SECTION_IFSET(CPU_FTR_HVMODE_206)
+END_FTR_SECTION_IFSET(CPU_FTR_HVMODE)
 #endif
 1:	mfsrr0	r3
 	mfsrr1	r4