[PATCH v2 03/20] KVM: s390: vsie: Add vsie_interp_extf detection

[Christoph Schlameuss <schlameuss@linux.ibm.com>]

Add sensing of the VSIE Interpretation Extension Facility as
vsie_interp_extf from SCLP. This facility is introduced with IBM Z
gen17.
Along with the new facility add a KVM struct member use_ssca that we
enable when the vsie_interp_extf is available.

Signed-off-by: Christoph Schlameuss <schlameuss@linux.ibm.com>
---
 arch/s390/include/asm/kvm_host.h | 1 +
 arch/s390/include/asm/sclp.h     | 1 +
 arch/s390/kvm/kvm-s390.c         | 1 +
 drivers/s390/char/sclp_early.c   | 1 +
 4 files changed, 4 insertions(+)

diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
index c172f9b212d1..6617d1161c68 100644
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -677,6 +677,7 @@ struct kvm_arch {
 	int use_pfmfi;
 	int use_skf;
 	int use_zpci_interp;
+	int use_ssca;
 	int user_cpu_state_ctrl;
 	int user_sigp;
 	int user_stsi;
diff --git a/arch/s390/include/asm/sclp.h b/arch/s390/include/asm/sclp.h
index f2d490558054..d790a5995103 100644
--- a/arch/s390/include/asm/sclp.h
+++ b/arch/s390/include/asm/sclp.h
@@ -102,6 +102,7 @@ struct sclp_info {
 	unsigned char has_dirq : 1;
 	unsigned char has_iplcc : 1;
 	unsigned char has_zpci_lsi : 1;
+	unsigned char has_vsie_interp_extf : 1;
 	unsigned char has_aisii : 1;
 	unsigned char has_aeni : 1;
 	unsigned char has_aisi : 1;
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index c679d8f83c0e..6f458e7b27e3 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -3380,6 +3380,7 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 
 	kvm->arch.use_pfmfi = sclp.has_pfmfi;
 	kvm->arch.use_skf = sclp.has_skey;
+	kvm->arch.use_ssca = sclp.has_vsie_interp_extf;
 	spin_lock_init(&kvm->arch.start_stop_lock);
 	kvm_s390_vsie_init(kvm);
 	if (use_gisa)
diff --git a/drivers/s390/char/sclp_early.c b/drivers/s390/char/sclp_early.c
index 22dd797e6229..40e6e346ee08 100644
--- a/drivers/s390/char/sclp_early.c
+++ b/drivers/s390/char/sclp_early.c
@@ -56,6 +56,7 @@ static void __init sclp_early_facilities_detect(void)
 		sclp.has_diag318 = !!(sccb->byte_134 & 0x80);
 		sclp.has_diag320 = !!(sccb->byte_134 & 0x04);
 		sclp.has_iplcc = !!(sccb->byte_134 & 0x02);
+		sclp.has_vsie_interp_extf = !!(sccb->byte_134 & 0x01);
 	}
 	if (sccb->cpuoff > 137) {
 		sclp.has_sipl = !!(sccb->cbl & 0x4000);

-- 
2.55.0