feat(sme): enable SME2 functionality for NS world
FEAT_SME2 is an extension of FEAT_SME and an optional feature
from v9.2. Its an extension of SME, wherein it not only
processes matrix operations efficiently, but also provides
outer-product instructions to accelerate matrix operations.
It affords instructions for multi-vector operations.
Further, it adds an 512 bit architectural register ZT0.
This patch implements all the changes introduced with FEAT_SME2
to ensure that the instructions are allowed to access ZT0
register from Non-secure lower exception levels.
Additionally, it adds support to ensure FEAT_SME2 is aligned
with the existing FEATURE DETECTION mechanism, and documented.
Change-Id: Iee0f61943304a9cfc3db8f986047b1321d0a6463
Signed-off-by: Jayanth Dodderi Chidanand <jayanthdodderi.chidanand@arm.com>
diff --git a/Makefile b/Makefile
index 5306ddf..892c2c9 100644
--- a/Makefile
+++ b/Makefile
@@ -861,8 +861,12 @@
$(info FEATURE_DETECTION is an experimental feature)
endif
-ifneq ($(ENABLE_SME_FOR_NS), 0)
- $(info ENABLE_SME_FOR_NS is an experimental feature)
+ifneq ($(ENABLE_SME2_FOR_NS), 0)
+ ifeq (${ENABLE_SME_FOR_NS}, 0)
+ $(warning "ENABLE_SME2_FOR_NS requires ENABLE_SME_FOR_NS also to be set")
+ $(warning "Forced ENABLE_SME_FOR_NS=1")
+ override ENABLE_SME_FOR_NS := 1
+ endif
endif
ifeq (${ARM_XLAT_TABLES_LIB_V1}, 1)
@@ -884,6 +888,7 @@
ifneq (${ENABLE_SME_FOR_NS},0)
$(error "ENABLE_SME_FOR_NS cannot be used with ARCH=aarch32")
endif
+
ifeq (${ENABLE_SVE_FOR_NS},1)
# Warning instead of error due to CI dependency on this
$(error "ENABLE_SVE_FOR_NS cannot be used with ARCH=aarch32")
@@ -925,6 +930,7 @@
ifneq (${ENABLE_SME_FOR_NS},0)
$(error "ENABLE_SME_FOR_NS cannot be used with CTX_INCLUDE_FPREGS")
endif
+
ifeq (${ENABLE_SVE_FOR_NS},1)
# Warning instead of error due to CI dependency on this
$(warning "ENABLE_SVE_FOR_NS cannot be used with CTX_INCLUDE_FPREGS")
@@ -1196,6 +1202,7 @@
ENABLE_SPE_FOR_NS \
ENABLE_SYS_REG_TRACE_FOR_NS \
ENABLE_SME_FOR_NS \
+ ENABLE_SME2_FOR_NS \
ENABLE_SVE_FOR_NS \
ENABLE_TRF_FOR_NS \
FW_ENC_STATUS \
@@ -1251,6 +1258,7 @@
ENABLE_RME \
ENABLE_RUNTIME_INSTRUMENTATION \
ENABLE_SME_FOR_NS \
+ ENABLE_SME2_FOR_NS \
ENABLE_SME_FOR_SWD \
ENABLE_SPE_FOR_NS \
ENABLE_SVE_FOR_NS \
diff --git a/changelog.yaml b/changelog.yaml
index d54c62b..6dbb9b2 100644
--- a/changelog.yaml
+++ b/changelog.yaml
@@ -128,7 +128,7 @@
- title: Trapping support for RNDR/RNDRRS (FEAT_RNG_TRAP)
scope: rng-trap
- - title: Scalable Matrix Extension (FEAT_SME)
+ - title: Scalable Matrix Extension (FEAT_SME, FEAT_SME2)
scope: sme
- title: Statistical profiling Extension (FEAT_SPE)
diff --git a/common/feat_detect.c b/common/feat_detect.c
index c8a0703..eb4db95 100644
--- a/common/feat_detect.c
+++ b/common/feat_detect.c
@@ -218,6 +218,8 @@
/* v9.2 features */
check_feature(ENABLE_SME_FOR_NS, read_feat_sme_id_field(),
"SME", 1, 2);
+ check_feature(ENABLE_SME2_FOR_NS, read_feat_sme_id_field(),
+ "SME2", 2, 2);
/* v9.4 features */
check_feature(ENABLE_FEAT_GCS, read_feat_gcs_id_field(), "GCS", 1, 1);
diff --git a/docs/getting_started/build-options.rst b/docs/getting_started/build-options.rst
index d2f463f..2229591 100644
--- a/docs/getting_started/build-options.rst
+++ b/docs/getting_started/build-options.rst
@@ -442,6 +442,13 @@
build with these options will fail. This flag can take the values 0 to 2, to
align with the ``FEATURE_DETECTION`` mechanism. Default is 0.
+- ``ENABLE_SME2_FOR_NS``: Numeric value to enable Scalable Matrix Extension
+ version 2 (SME2) for the non-secure world only. SME2 is an optional
+ architectural feature for AArch64 and TF-A support is experimental.
+ This should be set along with ENABLE_SME_FOR_NS=1, if not, the default SME
+ accesses will still be trapped. This flag can take the values 0 to 2, to
+ align with the ``FEATURE_DETECTION`` mechanism. Default is 0.
+
- ``ENABLE_SME_FOR_SWD``: Boolean option to enable the Scalable Matrix
Extension for secure world use along with SVE and FPU/SIMD, ENABLE_SME_FOR_NS
must also be set to use this. If enabling this, the secure world MUST
diff --git a/include/arch/aarch64/arch.h b/include/arch/aarch64/arch.h
index 9e061bf..ac5eae2 100644
--- a/include/arch/aarch64/arch.h
+++ b/include/arch/aarch64/arch.h
@@ -412,6 +412,7 @@
#define ID_AA64PFR1_EL1_SME_MASK ULL(0xf)
#define ID_AA64PFR1_EL1_SME_NOT_SUPPORTED ULL(0x0)
#define ID_AA64PFR1_EL1_SME_SUPPORTED ULL(0x1)
+#define ID_AA64PFR1_EL1_SME2_SUPPORTED ULL(0x2)
/* ID_PFR1_EL1 definitions */
#define ID_PFR1_VIRTEXT_SHIFT U(12)
@@ -519,6 +520,8 @@
#define CPACR_EL1_FP_TRAP_EL0 UL(0x1)
#define CPACR_EL1_FP_TRAP_ALL UL(0x2)
#define CPACR_EL1_FP_TRAP_NONE UL(0x3)
+#define CPACR_EL1_SMEN_SHIFT U(24)
+#define CPACR_EL1_SMEN_MASK ULL(0x3)
/* SCR definitions */
#define SCR_RES1_BITS ((U(1) << 4) | (U(1) << 5))
@@ -1026,11 +1029,16 @@
#define ID_AA64SMFR0_EL1_SME_FA64_SHIFT U(63)
#define ID_AA64SMFR0_EL1_SME_FA64_MASK U(0x1)
#define ID_AA64SMFR0_EL1_SME_FA64_SUPPORTED U(0x1)
+#define ID_AA64SMFR0_EL1_SME_VER_SHIFT U(55)
+#define ID_AA64SMFR0_EL1_SME_VER_MASK ULL(0xf)
+#define ID_AA64SMFR0_EL1_SME_INST_SUPPORTED ULL(0x0)
+#define ID_AA64SMFR0_EL1_SME2_INST_SUPPORTED ULL(0x1)
/* SMCR_ELx definitions */
#define SMCR_ELX_LEN_SHIFT U(0)
-#define SMCR_ELX_LEN_MASK U(0x1ff)
+#define SMCR_ELX_LEN_MAX U(0x1ff)
#define SMCR_ELX_FA64_BIT (U(1) << 31)
+#define SMCR_ELX_EZT0_BIT (U(1) << 30)
/*******************************************************************************
* Definitions of MAIR encodings for device and normal memory
diff --git a/include/arch/aarch64/arch_features.h b/include/arch/aarch64/arch_features.h
index 40ab82f..a0141de 100644
--- a/include/arch/aarch64/arch_features.h
+++ b/include/arch/aarch64/arch_features.h
@@ -657,4 +657,17 @@
return read_feat_sme_id_field() >= ID_AA64PFR1_EL1_SME_SUPPORTED;
}
+static inline bool is_feat_sme2_supported(void)
+{
+ if (ENABLE_SME2_FOR_NS == FEAT_STATE_DISABLED) {
+ return false;
+ }
+
+ if (ENABLE_SME2_FOR_NS == FEAT_STATE_ALWAYS) {
+ return true;
+ }
+
+ return read_feat_sme_id_field() >= ID_AA64PFR1_EL1_SME2_SUPPORTED;
+}
+
#endif /* ARCH_FEATURES_H */
diff --git a/lib/extensions/sme/sme.c b/lib/extensions/sme/sme.c
index 29034fd..f888d12 100644
--- a/lib/extensions/sme/sme.c
+++ b/lib/extensions/sme/sme.c
@@ -43,11 +43,23 @@
* to be the least restrictive, then lower ELs can restrict as needed
* using SMCR_EL2 and SMCR_EL1.
*/
- reg = SMCR_ELX_LEN_MASK;
+ reg = SMCR_ELX_LEN_MAX;
+
if (read_feat_sme_fa64_id_field() != 0U) {
VERBOSE("[SME] FA64 enabled\n");
reg |= SMCR_ELX_FA64_BIT;
}
+
+ /*
+ * Enable access to ZT0 register.
+ * Make sure FEAT_SME2 is supported by the hardware before continuing.
+ * If supported, Set the EZT0 bit in SMCR_EL3 to allow instructions to
+ * access ZT0 register without trapping.
+ */
+ if (is_feat_sme2_supported()) {
+ VERBOSE("SME2 enabled\n");
+ reg |= SMCR_ELX_EZT0_BIT;
+ }
write_smcr_el3(reg);
/* Reset CPTR_EL3 value. */
diff --git a/make_helpers/defaults.mk b/make_helpers/defaults.mk
index 34a9bc6..021893c 100644
--- a/make_helpers/defaults.mk
+++ b/make_helpers/defaults.mk
@@ -405,6 +405,9 @@
override ENABLE_SVE_FOR_SWD := 0
endif
+# SME2 defaults to disabled
+ENABLE_SME2_FOR_NS := 0
+
SANITIZE_UB := off
# For ARMv8.1 (AArch64) platforms, enabling this option selects the spinlock
diff --git a/plat/arm/board/fvp/platform.mk b/plat/arm/board/fvp/platform.mk
index 214064b..26843e4 100644
--- a/plat/arm/board/fvp/platform.mk
+++ b/plat/arm/board/fvp/platform.mk
@@ -55,6 +55,7 @@
ifeq (${ENABLE_RME}, 0)
ifeq (${CTX_INCLUDE_FPREGS}, 0)
ENABLE_SME_FOR_NS := 2
+ ENABLE_SME2_FOR_NS := 2
endif
endif
endif