On failure we log the actual and expected value of the register we detect
a mismatch in. For SME one obvious potential source of corruption would be
if we had corrupted SVCR since changes in streaming mode will reset the
register values, log the value to aid in understanding issues.

Signed-off-by: Mark Brown <broonie@kernel.org>
---
 tools/testing/selftests/arm64/fp/sve-test.S | 10 ++++++++++
 tools/testing/selftests/arm64/fp/za-test.S  |  6 ++++++
 tools/testing/selftests/arm64/fp/zt-test.S  |  5 +++++
 3 files changed, 21 insertions(+)

diff --git a/tools/testing/selftests/arm64/fp/sve-test.S b/tools/testing/selftests/arm64/fp/sve-test.S
index 547d077e3517..fff60e2a25ad 100644
--- a/tools/testing/selftests/arm64/fp/sve-test.S
+++ b/tools/testing/selftests/arm64/fp/sve-test.S
@@ -515,6 +515,10 @@ function barf
 	mov	x11, x1	// actual data
 	mov	x12, x2	// data size
 
+#ifdef SSVE
+	mrs	x13, S3_3_C4_C2_2
+#endif
+
 	puts	"Mismatch: PID="
 	mov	x0, x20
 	bl	putdec
@@ -534,6 +538,12 @@ function barf
 	bl	dumphex
 	puts	"]\n"
 
+#ifdef SSVE
+	puts	"\tSVCR: "
+	mov	x0, x13
+	bl	putdecn
+#endif
+
 	mov	x8, #__NR_getpid
 	svc	#0
 // fpsimd.c acitivty log dump hack
diff --git a/tools/testing/selftests/arm64/fp/za-test.S b/tools/testing/selftests/arm64/fp/za-test.S
index 9dcd70911397..095b45531640 100644
--- a/tools/testing/selftests/arm64/fp/za-test.S
+++ b/tools/testing/selftests/arm64/fp/za-test.S
@@ -333,6 +333,9 @@ function barf
 //	mov	w8, #__NR_exit
 //	svc	#0
 // end hack
+
+	mrs	x13, S3_3_C4_C2_2
+
 	smstop
 	mov	x10, x0	// expected data
 	mov	x11, x1	// actual data
@@ -356,6 +359,9 @@ function barf
 	mov	x1, x12
 	bl	dumphex
 	puts	"]\n"
+	puts	"\tSVCR: "
+	mov	x0, x13
+	bl	putdecn
 
 	mov	x8, #__NR_getpid
 	svc	#0
diff --git a/tools/testing/selftests/arm64/fp/zt-test.S b/tools/testing/selftests/arm64/fp/zt-test.S
index d63286397638..b5c81e81a379 100644
--- a/tools/testing/selftests/arm64/fp/zt-test.S
+++ b/tools/testing/selftests/arm64/fp/zt-test.S
@@ -267,6 +267,8 @@ function barf
 //	mov	w8, #__NR_exit
 //	svc	#0
 // end hack
+
+	mrs	x13, S3_3_C4_C2_2
 	smstop
 	mov	x10, x0	// expected data
 	mov	x11, x1	// actual data
@@ -287,6 +289,9 @@ function barf
 	mov	x1, x12
 	bl	dumphex
 	puts	"]\n"
+	puts	"\tSVCR: "
+	mov	x0, x13
+	bl	putdecn
 
 	mov	x8, #__NR_getpid
 	svc	#0

---
base-commit: 2cc14f52aeb78ce3f29677c2de1f06c0e91471ab
change-id: 20231204-arm64-kselftest-log-svcr-372a210520ae

Best regards,
-- 
Mark Brown <broonie@kernel.org>

On Tue, 05 Dec 2023 14:24:44 +0000, Mark Brown wrote:
> On failure we log the actual and expected value of the register we detect
> a mismatch in. For SME one obvious potential source of corruption would be
> if we had corrupted SVCR since changes in streaming mode will reset the
> register values, log the value to aid in understanding issues.
> 
> 

Applied to arm64 (for-next/selftests), thanks!

[1/1] kselftest/arm64: Log SVCR when the SME tests barf
      https://git.kernel.org/arm64/c/48f7ab21f731

Cheers,
-- 
Will

https://fixes.arm64.dev
https://next.arm64.dev
https://will.arm64.dev