From ef939f30510b43e90f1fba30477b678107faeae7 Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Tue, 13 Sep 2022 15:11:01 +0100 Subject: kselftest/arm64: Add hwcap test for RNG Validate the RNG hwcap and make sure we don't generate a SIGILL reading RNDR when it is reported. Signed-off-by: Mark Brown Link: https://lore.kernel.org/r/20220913141101.151400-4-broonie@kernel.org Signed-off-by: Catalin Marinas --- tools/testing/selftests/arm64/abi/hwcap.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/tools/testing/selftests/arm64/abi/hwcap.c b/tools/testing/selftests/arm64/abi/hwcap.c index 6c91b4a0987e..d173e41f2123 100644 --- a/tools/testing/selftests/arm64/abi/hwcap.c +++ b/tools/testing/selftests/arm64/abi/hwcap.c @@ -33,6 +33,11 @@ */ typedef void (*sigill_fn)(void); +static void rng_sigill(void) +{ + asm volatile("mrs x0, S3_3_C2_C4_0" : : : "x0"); +} + static void sme_sigill(void) { /* RDSVL x0, #0 */ @@ -113,6 +118,13 @@ static const struct hwcap_data { sigill_fn sigill_fn; bool sigill_reliable; } hwcaps[] = { + { + .name = "RNG", + .at_hwcap = AT_HWCAP2, + .hwcap_bit = HWCAP2_RNG, + .cpuinfo = "rng", + .sigill_fn = rng_sigill, + }, { .name = "SME", .at_hwcap = AT_HWCAP2, -- cgit v1.2.3-59-g8ed1b