[kvm-unit-tests PATCH v5 2/4] s390x: sclp: add service call instruction wrapper

Claudio Imbrenda
2020-01-08T16:13:26Z

Add a wrapper for the service call instruction, and use it for SCLP
interactions instead of using inline assembly everywhere.

Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
---
lib/s390x/asm/arch_def.h | 13 +++++++++++++
lib/s390x/sclp.c | 7 +------
2 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/lib/s390x/asm/arch_def.h b/lib/s390x/asm/arch_def.h
index cf6e1ca..1a5e3c6 100644
--- a/lib/s390x/asm/arch_def.h
+++ b/lib/s390x/asm/arch_def.h
@@ -271,4 +271,17 @@ static inline int stsi(void *addr, int fc, int sel1, int sel2)
return cc;
}

+static inline int servc(uint32_t command, unsigned long sccb)
+{
+ int cc;
+
+ asm volatile(
+ " .insn rre,0xb2200000,%1,%2\n" /* servc %1,%2 */
+ " ipm %0\n"
+ " srl %0,28"
+ : "=&d" (cc) : "d" (command), "a" (sccb)
+ : "cc", "memory");
+ return cc;
+}
+
#endif
diff --git a/lib/s390x/sclp.c b/lib/s390x/sclp.c
index 123b639..4054d0e 100644
--- a/lib/s390x/sclp.c
+++ b/lib/s390x/sclp.c
@@ -116,12 +116,7 @@ int sclp_service_call(unsigned int command, void *sccb)
int cc;

sclp_setup_int();
- asm volatile(
- " .insn rre,0xb2200000,%1,%2\n" /* servc %1,%2 */
- " ipm %0\n"
- " srl %0,28"
- : "=&d" (cc) : "d" (command), "a" (__pa(sccb))
- : "cc", "memory");
+ cc = servc(command, __pa(sccb));
sclp_wait_busy();
if (cc == 3)
return -1;
--
2.24.1