feat(sme): enable SME functionality
This patch adds two new compile time options to enable SME in TF-A:
ENABLE_SME_FOR_NS and ENABLE_SME_FOR_SWD for use in non-secure and
secure worlds respectively. Setting ENABLE_SME_FOR_NS=1 will enable
SME for non-secure worlds and trap SME, SVE, and FPU/SIMD instructions
in secure context. Setting ENABLE_SME_FOR_SWD=1 will disable these
traps, but support for SME context management does not yet exist in
SPM so building with SPD=spmd will fail.
The existing ENABLE_SVE_FOR_NS and ENABLE_SVE_FOR_SWD options cannot
be used with SME as it is a superset of SVE and will enable SVE and
FPU/SIMD along with SME.
Signed-off-by: John Powell <john.powell@arm.com>
Change-Id: Iaaac9d22fe37b4a92315207891da848a8fd0ed73
diff --git a/include/lib/extensions/sme.h b/include/lib/extensions/sme.h
new file mode 100644
index 0000000..893f9f2
--- /dev/null
+++ b/include/lib/extensions/sme.h
@@ -0,0 +1,27 @@
+/*
+ * Copyright (c) 2021, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef SME_H
+#define SME_H
+
+#include <stdbool.h>
+
+#include <context.h>
+
+/*
+ * Maximum value of LEN field in SMCR_ELx. This is different than the maximum
+ * supported value which is platform dependent. In the first version of SME the
+ * LEN field is limited to 4 bits but will be expanded in future iterations.
+ * To support different versions, the code that discovers the supported vector
+ * lengths will write the max value into SMCR_ELx then read it back to see how
+ * many bits are implemented.
+ */
+#define SME_SMCR_LEN_MAX U(0x1FF)
+
+void sme_enable(cpu_context_t *context);
+void sme_disable(cpu_context_t *context);
+
+#endif /* SME_H */
diff --git a/include/lib/extensions/sve.h b/include/lib/extensions/sve.h
index c85e08c..4b66cdb 100644
--- a/include/lib/extensions/sve.h
+++ b/include/lib/extensions/sve.h
@@ -10,5 +10,6 @@
#include <context.h>
void sve_enable(cpu_context_t *context);
+void sve_disable(cpu_context_t *context);
#endif /* SVE_H */