1 files changed, 50 insertions, 0 deletions
diff --git a/tools/testing/selftests/kvm/include/s390x/facility.h b/tools/testing/selftests/kvm/include/s390x/facility.h
new file mode 100644
index 000000000000..00a1ced6538b
--- /dev/null
+++ b/tools/testing/selftests/kvm/include/s390x/facility.h
@@ -0,0 +1,50 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright IBM Corp. 2024
+ *
+ * Authors:
+ *  Hariharan Mari <hari55@linux.ibm.com>
+ *
+ * Get the facility bits with the STFLE instruction
+ */
+
+#ifndef SELFTEST_KVM_FACILITY_H
+#define SELFTEST_KVM_FACILITY_H
+
+#include <linux/bitops.h>
+
+/* alt_stfle_fac_list[16] + stfle_fac_list[16] */
+#define NB_STFL_DOUBLEWORDS 32
+
+extern uint64_t stfl_doublewords[NB_STFL_DOUBLEWORDS];
+extern bool stfle_flag;
+
+static inline bool test_bit_inv(unsigned long nr, const unsigned long *ptr)
+{
+	return test_bit(nr ^ (BITS_PER_LONG - 1), ptr);
+}
+
+static inline void stfle(uint64_t *fac, unsigned int nb_doublewords)
+{
+	register unsigned long r0 asm("0") = nb_doublewords - 1;
+
+	asm volatile("	.insn	s,0xb2b00000,0(%1)\n"
+			: "+d" (r0)
+			: "a" (fac)
+			: "memory", "cc");
+}
+
+static inline void setup_facilities(void)
+{
+	stfle(stfl_doublewords, NB_STFL_DOUBLEWORDS);
+	stfle_flag = true;
+}
+
+static inline bool test_facility(int nr)
+{
+	if (!stfle_flag)
+		setup_facilities();
+	return test_bit_inv(nr, stfl_doublewords);
+}
+
+#endif