[PULL 26/36] KVM: PPC: Book3S HV: Implement architecture compatibility modes for POWER8

Alexander Graf
2014-01-29T16:13:26Z

From: Paul Mackerras <paulus@samba.org>

This allows us to select architecture 2.05 (POWER6) or 2.06 (POWER7)
compatibility modes on a POWER8 processor. (Note that transactional
memory is disabled for usermode if either or both of the PCR_TM_DIS
and PCR_ARCH_206 bits are set.)

Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
---
arch/powerpc/include/asm/reg.h | 2 ++
arch/powerpc/kvm/book3s_hv.c | 16 +++++++++++++++-
2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h
index 2f41e64..5a99831 100644
--- a/arch/powerpc/include/asm/reg.h
+++ b/arch/powerpc/include/asm/reg.h
@@ -329,6 +329,8 @@
#define SPRN_PCR 0x152 /* Processor compatibility register */
#define PCR_VEC_DIS (1ul << (63-0)) /* Vec. disable (bit NA since POWER8) */
#define PCR_VSX_DIS (1ul << (63-1)) /* VSX disable (bit NA since POWER8) */
+#define PCR_TM_DIS (1ul << (63-2)) /* Trans. memory disable (POWER8) */
+#define PCR_ARCH_206 0x4 /* Architecture 2.06 */
#define PCR_ARCH_205 0x2 /* Architecture 2.05 */
#define SPRN_HEIR 0x153 /* Hypervisor Emulated Instruction Register */
#define SPRN_TLBINDEXR 0x154 /* P7 TLB control register */
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 1bf681e..1e9f4b45 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -184,14 +184,28 @@ int kvmppc_set_arch_compat(struct kvm_vcpu *vcpu, u32 arch_compat)

switch (arch_compat) {
case PVR_ARCH_205:
- pcr = PCR_ARCH_205;
+ /*
+ * If an arch bit is set in PCR, all the defined
+ * higher-order arch bits also have to be set.
+ */
+ pcr = PCR_ARCH_206 | PCR_ARCH_205;
break;
case PVR_ARCH_206:
case PVR_ARCH_206p:
+ pcr = PCR_ARCH_206;
+ break;
+ case PVR_ARCH_207:
break;
default:
return -EINVAL;
}
+
+ if (!cpu_has_feature(CPU_FTR_ARCH_207S)) {
+ /* POWER7 can't emulate POWER8 */
+ if (!(pcr & PCR_ARCH_206))
+ return -EINVAL;
+ pcr &= ~PCR_ARCH_206;
+ }
}

spin_lock(&vc->lock);
--
1.8.1.4