On 8/9/21 12:03 PM, Claudio Imbrenda wrote:

On Mon,  9 Aug 2021 10:48:53 +0200
Pierre Morel [off-list ref] wrote:

quoted

We check the PTF instruction.

- We do not expect to support vertical polarization.

- We do not expect the Modified Topology Change Report to be
pending or not at the moment the first PTF instruction with
PTF_CHECK function code is done as some code already did run
a polarization change may have occur.

Signed-off-by: Pierre Morel <redacted>
---
  s390x/Makefile      |  1 +
  s390x/topology.c    | 87
+++++++++++++++++++++++++++++++++++++++++++++ s390x/unittests.cfg |
3 ++ 3 files changed, 91 insertions(+)
  create mode 100644 s390x/topology.c

diff --git a/s390x/Makefile b/s390x/Makefile
index 6565561b..c82b7dbf 100644
--- a/s390x/Makefile
+++ b/s390x/Makefile

@@ -24,6 +24,7 @@ tests += $(TEST_DIR)/mvpg.elf
  tests += $(TEST_DIR)/uv-host.elf
  tests += $(TEST_DIR)/edat.elf
  tests += $(TEST_DIR)/mvpg-sie.elf
+tests += $(TEST_DIR)/topology.elf
  
  tests_binary = $(patsubst %.elf,%.bin,$(tests))
  ifneq ($(HOST_KEY_DOCUMENT),)

diff --git a/s390x/topology.c b/s390x/topology.c
new file mode 100644
index 00000000..4146189a
--- /dev/null
+++ b/s390x/topology.c

@@ -0,0 +1,87 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * CPU Topology
+ *
+ * Copyright (c) 2021 IBM Corp
+ *
+ * Authors:
+ *  Pierre Morel <pmorel@linux.ibm.com>
+ */
+
+#include <libcflat.h>
+#include <asm/page.h>
+#include <asm/asm-offsets.h>
+#include <asm/interrupt.h>
+#include <asm/facility.h>
+#include <smp.h>
+#include <sclp.h>
+
+static uint8_t pagebuf[PAGE_SIZE * 2]

__attribute__((aligned(PAGE_SIZE * 2))); +int machine_level;
+int mnest;
+
+#define PTF_HORIZONTAL	0
+#define PTF_VERTICAL	1
+#define PTF_CHECK	2
+
+#define PTF_ERR_NO_REASON	0
+#define PTF_ERR_ALRDY_POLARIZED	1
+#define PTF_ERR_IN_PROGRESS	2
+
+static int ptf(unsigned long fc, unsigned long *rc)
+{
+	int cc;
+
+	asm volatile(
+		"       .insn   rre,0xb9a20000,%1,%1\n"

I know you copied this from the kernel, but the second argument is not
really there according to the PoP, so maybe it's better to have this
instead?

	.insn   rre,0xb9a20000,%1,0\n

OK, thanks.

quoted

+		"       ipm     %0\n"
+		"       srl     %0,28\n"
+		: "=d" (cc), "+d" (fc)
+		: "d" (fc)
+		: "cc");
+
+	*rc = fc >> 8;
+	return cc;
+}
+
+static void test_ptf(void)
+{
+	unsigned long rc;
+	int cc;
+
+	report_prefix_push("Topology Report pending");
+	/*
+	 * At this moment the topology may already have changed
+	 * since the VM has been started.
+	 * However, we can test if a second PTF instruction
+	 * reports that the topology did not change since the
+	 * preceding PFT instruction.
+	 */
+	ptf(PTF_CHECK, &rc);
+	cc = ptf(PTF_CHECK, &rc);
+	report(cc == 0, "PTF check clear");
+	cc = ptf(PTF_HORIZONTAL, &rc);
+	report(cc == 2 && rc == PTF_ERR_ALRDY_POLARIZED,
+	       "PTF horizontal already configured");
+	cc = ptf(PTF_VERTICAL, &rc);
+	report(cc == 2 && rc == PTF_ERR_NO_REASON,
+	       "PTF vertical non possible");

*not possible

Oh yes :)

quoted

+
+	report_prefix_pop();
+}
+
+int main(int argc, char *argv[])
+{
+	report_prefix_push("stsi");

should this really be "stsi" ?

No, I think CPU-Topology should be better.




-- 
Pierre Morel
IBM Lab Boeblingen