KVM: PPC: Book3S: Add count cache flush parameters to kvmppc_get_cpu_char()

Add KVM_PPC_CPU_CHAR_BCCTR_FLUSH_ASSIST &
KVM_PPC_CPU_BEHAV_FLUSH_COUNT_CACHE to the characteristics returned
from the H_GET_CPU_CHARACTERISTICS H-CALL, as queried from either the
hypervisor or the device tree.
Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>

arch/powerpc/include/uapi/asm/kvm.h

@@ -463,10 +463,12 @@ struct kvm_ppc_cpu_char {
 #define KVM_PPC_CPU_CHAR_BR_HINT_HONOURED	(1ULL << 58)
 #define KVM_PPC_CPU_CHAR_MTTRIG_THR_RECONF	(1ULL << 57)
 #define KVM_PPC_CPU_CHAR_COUNT_CACHE_DIS	(1ULL << 56)
+#define KVM_PPC_CPU_CHAR_BCCTR_FLUSH_ASSIST	(1ull << 54)
 
 #define KVM_PPC_CPU_BEHAV_FAVOUR_SECURITY	(1ULL << 63)
 #define KVM_PPC_CPU_BEHAV_L1D_FLUSH_PR		(1ULL << 62)
 #define KVM_PPC_CPU_BEHAV_BNDS_CHK_SPEC_BAR	(1ULL << 61)
+#define KVM_PPC_CPU_BEHAV_FLUSH_COUNT_CACHE	(1ull << 58)
 
 /* Per-vcpu XICS interrupt controller state */
 #define KVM_REG_PPC_ICP_STATE	(KVM_REG_PPC | KVM_REG_SIZE_U64 | 0x8c)

arch/powerpc/kvm/powerpc.c

@@ -2189,10 +2189,12 @@ static int pseries_get_cpu_char(struct kvm_ppc_cpu_char *cp)
 			KVM_PPC_CPU_CHAR_L1D_THREAD_PRIV |
 			KVM_PPC_CPU_CHAR_BR_HINT_HONOURED |
 			KVM_PPC_CPU_CHAR_MTTRIG_THR_RECONF |
-			KVM_PPC_CPU_CHAR_COUNT_CACHE_DIS;
+			KVM_PPC_CPU_CHAR_COUNT_CACHE_DIS |
+			KVM_PPC_CPU_CHAR_BCCTR_FLUSH_ASSIST;
 		cp->behaviour_mask = KVM_PPC_CPU_BEHAV_FAVOUR_SECURITY |
 			KVM_PPC_CPU_BEHAV_L1D_FLUSH_PR |
-			KVM_PPC_CPU_BEHAV_BNDS_CHK_SPEC_BAR;
+			KVM_PPC_CPU_BEHAV_BNDS_CHK_SPEC_BAR |
+			KVM_PPC_CPU_BEHAV_FLUSH_COUNT_CACHE;
 	}
 	return 0;
 }
@@ -2251,12 +2253,16 @@ static int kvmppc_get_cpu_char(struct kvm_ppc_cpu_char *cp)
 		if (have_fw_feat(fw_features, "enabled",
 				 "fw-count-cache-disabled"))
 			cp->character |= KVM_PPC_CPU_CHAR_COUNT_CACHE_DIS;
+		if (have_fw_feat(fw_features, "enabled",
+				 "fw-count-cache-flush-bcctr2,0,0"))
+			cp->character |= KVM_PPC_CPU_CHAR_BCCTR_FLUSH_ASSIST;
 		cp->character_mask = KVM_PPC_CPU_CHAR_SPEC_BAR_ORI31 |
 			KVM_PPC_CPU_CHAR_BCCTRL_SERIALISED |
 			KVM_PPC_CPU_CHAR_L1D_FLUSH_ORI30 |
 			KVM_PPC_CPU_CHAR_L1D_FLUSH_TRIG2 |
 			KVM_PPC_CPU_CHAR_L1D_THREAD_PRIV |
-			KVM_PPC_CPU_CHAR_COUNT_CACHE_DIS;
+			KVM_PPC_CPU_CHAR_COUNT_CACHE_DIS |
+			KVM_PPC_CPU_CHAR_BCCTR_FLUSH_ASSIST;
 
 		if (have_fw_feat(fw_features, "enabled",
 				 "speculation-policy-favor-security"))
@@ -2267,9 +2273,13 @@ static int kvmppc_get_cpu_char(struct kvm_ppc_cpu_char *cp)
 		if (!have_fw_feat(fw_features, "disabled",
 				  "needs-spec-barrier-for-bound-checks"))
 			cp->behaviour |= KVM_PPC_CPU_BEHAV_BNDS_CHK_SPEC_BAR;
+		if (have_fw_feat(fw_features, "enabled",
+				 "needs-count-cache-flush-on-context-switch"))
+			cp->behaviour |= KVM_PPC_CPU_BEHAV_FLUSH_COUNT_CACHE;
 		cp->behaviour_mask = KVM_PPC_CPU_BEHAV_FAVOUR_SECURITY |
 			KVM_PPC_CPU_BEHAV_L1D_FLUSH_PR |
-			KVM_PPC_CPU_BEHAV_BNDS_CHK_SPEC_BAR;
+			KVM_PPC_CPU_BEHAV_BNDS_CHK_SPEC_BAR |
+			KVM_PPC_CPU_BEHAV_FLUSH_COUNT_CACHE;
 
 		of_node_put(fw_features);
 	}